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城市轨道交通专业英语


市轨道 运营管 城市轨道交通运营管理专业

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List
Chapter 1: Development of Urban Rail Transit Speeds up in China ........... 3

Chapter 2 Rapid Transit ........................................................................... 12

Chapter 3

RAIL TRANSIT IN NORTH AMERICA ............................. 23

Chapter 4 The Railroad Track................................................................... 40

Chapter 5 General Vehicle Description ..................................................... 45

Chapter 6

ATP Transmission and Moving Block ................................... 53

Chapter 7

Control of Railway Operation ............................................. 62

Chapter 8

Train Station Passenger Flow Study ...................................... 74

Chapter 9

Metrocard Fare Incentives ..................................................... 81

Chapter 10 Audible Information Design in the New York City Subway ... 86

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Chapter 1: Development of Urban Rail Transit Speeds up in China
With the development of urban rail transit, on the one hand, it is promoting the process of urban modernization, alleviating congested traffic in cities, and narrowing the distance between time and space. On the other hand, it changes the way people travel, accelerates the pace of their life and work, and affects the quality of life. The state of urban rail transit reflects a country's comprehensive strength and is a symbol of a city's modernization level. At present, rail transit system is available in 135 cities in nearly 40 countries and regions. In cosmopolitan cities, accounting for a proportion of 60 per cent - 80 per cent, rail transit has become the leading means of transportation in these cities. Yet so far, in Beijing, Shanghai, Tianjin and Guangzhou, etc., rail transit accounts for less than 10 percent in the cities total traffic capacity. Urban rail transit offers comprehensive advantages, like small land occupation, large traffic volume, high speed, non-pollution, low energy consumption, high safety and great comfort. With most facilities being installed underground and the operation going on underground, subways require very limited occupation of land, and do not compete with other means of transportation for space. Urban light rail, trolley bus as well as suburban rail and magnetic suspension train are basically railways, which makes it possible to make the most of land resources. Urban rail transit system offers immense transport capacity. During rush hours, the maximum unidirectional transport capacity may reach up to 60, 000- 80, 000 person-times per hour, which is unmatchable to other means of transportation. The hourly traveling speed of rail transit generally exceeds 70 kilometers-100 kilometers, offering high punctuality. Moreover, mostly being hauled by electric locomotives, rail transit requires low energy consumption, and it causes little pollution to cities. Therefore, it is called "green transportation". From a macro perspective, urban rail transit plays an important role in improving the structure of urban transport, alleviating urban ground traffic congestion, and promoting the utilization efficiency of urban land. Nevertheless, compared with other means of transportation, rail transit has some drawbacks, like long construction cycle, heavy initial investment, slow withdrawal of funds and poor economic benefits in operation. For example, currently the building of subway costs some RMB500 million-700 million per kilometer; urban light rail and magnetic suspension train, RMB200 million-300 million; trolley bus and suburban rail, about RMB100 million. In China, rail transit dates back to the late 1960s, when the first subway was built in
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Beijing. That was nearly one century later than developed countries in the West. However, since it made its debut, urban rail transit has helped ease the immense pressure caused by urban traffic congestion and brought great convenience and comfort to passengers. Take Beijing for example. Currently, subways provide a transport volume of approximately 1.5 million person-times per day. Without subways, the traffic congestion in this city would simply be inconceivable. At present, rail transit has evolved from the startup stage to a period of stable, sustainable and orderly development in this country. In China (excluding Hong Kong and Taiwan), the length of subways completed totals 193 kilometers; project urban rail under construction, 334 kilometers; planned urban rail, 420 kilometers. Among big cities with a population of over 2 million, those that already have or are building urban rail transit include Beijing, Tianjin, Shanghai, Guangzhou, Dalian, Shenzhen, Wuhan, Nanjing, Chongqing and Changchun. Now, seven cities have announced or are still working on their plan to build rail transit: Chengdu, Hangzhou, Shenyang, Xi'an, Harbin, Qingdao and Suzhou. According to plan, by 2008, there will be thirteen rail transit lines and two spur lines in Beijing, with a total length of 408.2 kilometers. In Shanghai, there will be 21 rail transit lines, totaling more than 500 kilometers in length. During the Tenth Five-Year Plan period, the total length will hit 780 kilometers. In Tianjin, there will be four subway lines, totaling 106 kilometers. That, coupled with 50 kilometers of suburban light rail and one loop subway 71-kilometers set aside, will bring the total length to 227 kilometers. Meanwhile, there will be seven rail transit lines totaling 206.48 kilometers in Guangzhou, and seven rail transit lines totaling 263.1 kilometers in Nanjing. With other cities' planning taken into account, the total length of rail transit lines will come to some 2, 200 kilometers in this country. At present, the constraints to the development of rail transit in China mainly lie in three aspects: First, there is severe shortage of construction funds. According to the foregoing planning, it is necessary to invest in approximately RMB300 billion. Projects to be completed by 2006 alone require more than RMB150 billion. Furthermore, in most cases, funds come from investments of the central and local governments as well as bank loans. Still a developing country as it is, China has very limited financial strength. Second, as rail transit is demanding on technical standard, some key technical facilities at low ratio of home mading at present largely rely on imports. Thus, construction cost remains hig h due to the import of large quantity of technolog y and equipment. Third, in most cases, rail transit operates at a loss in China. That aggregates the central
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and local governments' financial burdens, which, in return, checks the development of rail transit to some extent. For this reason, China formulated the guideline of "doing what the strength allows, implementing rules-based management and pursuing stable development". In the development of rail transit, it is required that homemade equipment should take up at least 70 per cent. Meanwhile, it is essential to ensure that development of rail transit suits the pace of economic development in the cities and prevent blind development and irrational attempts to advance forward.

Railway Terms and New Words
urban adj. 城市的, 市内的, urban rail transit(URT)城市轨道交通 alleviate vt. 减轻 congested adj. 拥挤的, congest vt., congestion n. accelerate v. 加速, 促进 comprehensive adj. 全面的,广泛的 cosmopolitan adj. 世界性的,全球(各地)的 proportion n. 比例, 均衡, 面积, 部分 underground adj. 地下的, 地面下的, 秘密的 n. [英] 地铁 adv. 秘密地 trolley bus n. 电车, (电车)滚轮, 手推车, 手摇车, 台车 magnetic adj. 磁的, 有磁性的, 有吸引力的 suspension n. 吊, 悬浮, 悬浮液, 暂停, 中止, 悬而未决, 延迟 basically adv. 基本上, 主要地 unidirectional adj. 单向的, 单向性的 the Tenth Five-Year Plan 第十个五年规划 at a loss 低于成本的 in return 作为报答 compete with 与…争夺, competition n.

Reading Material The Rising Motorization of China
China’s motorization rate has grown in accordance with other rapidly developing countries, but because of China’s high population, the impacts of motorization are potentially more severe. Figure 1 shows the exponential increase in personal automobile ownership rates. Currently, there are about seven personal automobiles per 1000 people,
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compared to over 700 vehicles per 1000 people in industrialized nations like the United States. This figure does not include privately owned trucks or publicly owned vehicles (including buses and trucks), which increases the number of automobiles to about 28 vehicles per 1000 people. If China were to achieve motorization rates comparable to those of developed countries, the environmental and economic consequences could be disastrous. By 2020, the total automobile fleet (not including motorcycles) is expected to grow by between three and seven times the current size depending on economic growth rates (NRC 2003).

The population distribution of China is diverse, with the majority of the population (60%) living in rural areas. However, in the past several decades, the improved economic situation of the cities has caused a rapid urban in-migration. This trend has resulted in a nearly three-fold increase in urban development and density in the last decade as displayed in Figure 2. Much of this development is not necessarily representative of sustainable transit and pedestrian oriented growth. Although this new development is very dense, low land cost at the periphery cause developers to build spatially separated housing and commercial developments with few transit connections to the urban center (Gaukenheimer 1996).

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The western provinces are the most sparsely populated with the largest urban population centers located in provinces along the eastern coast, in metropolises such as Shanghai, Beijing, and Guangzhou. These cities have been experiencing high motorization rates partially because of their higher incomes, but non-motorized modes still capture approximately 70% of the work trip commutes in these cities, while the personal automobile only accounts for 7% (Hu 2003). Much of the transportation and planning research has been centered on these cities, although they constitute a rather small portion of the entire population. Figure 3 shows the amount of cities of different sizes and the approximate total population of people living in cities of different size. Two thirds of the urban population resides in cities with populations between 0.5 and 2 million, indicating that much of the planning and transportation research related to China is focusing on problems that might not be relevant or applicable to the majority of the Chinese population. Economically, most of these cities are years or decades behind the more developed Chinese cities and have not developed many of the transportation problems Beijing, Shanghai and Guangzhou have. Focusing planning efforts in these cities could have much greater returns.

The Chinese economy has been growing at a phenomenal rate for the past decade and has doubled in size in the last nine years. In fact, the growth rate is so fast that the Chinese government is imposing several measures to try to control growth to keep it at a more sustainable level (Economist 2004). China’s growth has largely been a result of investment in a few “pillar” industries. The highest growing pillar industries are: electronic manufacturing, automobiles, electric power, and steel. The eighth five-year plan (1991-1995) designated the automobile industry as one of the pillar industries of economic development. This policy statement encourages the growth of an indigenous auto industry that will be able to supply a large portion of its domestic demand and create a strong export market. It calls for the consolidation of over one hundred companies into 3 or 4 large
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competitive companies. The auto industry accounts for 20% of Shanghai’s gross regional product (Hook 2002). However, with China’s entry into the World Trade Organization (WTO) in 2001, they must reduce tariffs on imported automobiles and can no longer protect their market. This has spurred development of the domestic automobile industry to a level that can compete with international competitors. One of the greatest challenges of cities in China is controlling automobile ownership growth, while fostering the national policy of growing the automobile industry.

Costs and Benefits of Motorization
The cost and benefit implications for Chinese motorization are enormous. Motorization is a major economic growth strategy. The government has adopted a strategy of developing an automobile manufacturing industry. Automobiles can also provide indirect economic benefits of decreased travel time, improved accessibility to goods and services, and new found mobility that will cause people to travel more and achieve a more mobile lifestyle that they would not have otherwise been able to experience. The potential costs are enormous. The United States has the highest motorization rate in the world and perhaps the most mature automobile industry. However, the US has also experienced very high costs associated with our level of motorization. The most obvious and potentially most severe cost is the air pollution and greenhouse gas emissions associated with the automobile. The US emits 26% of the global greenhouse gases but only constitutes 5% of the world’s population. China’s policy goal is to achieve Euro II emissions standards by 2005 (about a decade behind Europe) and be internationally compliant with Euro IV standards by 2010. This is a very ambitious goal, but it is necessary if Chinese automakers want to compete in the international market and improve the air quality in their own country. With the three to seven-fold growth rate anticipated in the next 15 years, CO2 emissions will likely quadruple, CO, and hydrocarbons will likely triple, and NOx and particulate matter will likely stay the same. This assumes an aggressive emissions regulation strategy and a modest economic growth rate (NRC 2003). The US EPA has identified all of these emissions as having serious health effects at high concentrations. From a global perspective, China’s motorization could have adverse effects on the global climate. Currently, the transportation sector accounts for 17% of the greenhouse emissions, but this proportion could increase significantly if the motorization trends continue. China is also the second highest consumer of oil in the world (behind the United States). If China motorizes as rapidly as expected, the increase demand could cause the global price of fuel to skyrocket.
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Another major issue associated with increased motorization is changes in land use. As incomes increase, people desire more living space, which reduces density and encourages expansion at the urban fringe. Figure 4 shows the growth of residential floor space per capita, which is a force toward lower density. This requires more auto oriented transportation infrastructure as well as more land for development. In Shanghai, approximately 10% of the land area is devoted to transportation infrastructure (compared to 20-25% in Europe) (Shen 1997). Because of the built environment, most of the new transportation infrastructure is expanding at the periphery, encouraging auto oriented developments. An increasingly open housing market, where people choose where to live is also creating a spatial jobs-housing imbalance that did not previously exist, when industry provided housing for its employees adjacent to their plants. This greatly increases the cost of transportation for Chinese households as indicated by Figure 5. The proportion of a households income spent on transportation has increases ten fold in less than 15 years. Another major consideration is the conservation of agricultural land. China currently has a very low amount of agricultural land per capita (World Bank 2001)and cannot afford to lose more through urban expansion (Franke 1997).

Additional costs include accidents and injuries associated with motorization. Currently, the fatality rate (deaths per mile of travel) is 30 times that of the United States, with over 100,000 deaths per year since 2001, many of which are pedestrians and bicyclists (NRC 2003, Hook 2002b). Additionally equity issues must be considered, specifically the dislocation of the poor. Even with the high projected growth rates in automobile ownership, most Chinese will not own vehicles, so alternative modes must be supplied that can serve the increasing spatial separation between origins and destinations. The cost of the required infrastructure will be enormous and the government will likely have to provide more subsidies to the transportation sector, potentially restricting its investment in other sectors.
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Causes of Motorization
The primary impetus for the motorization of China has been the rapid growth of the economy. With a rise in the economic growth of a country comes a desire and means to become more motorized. Motorization rates are associated with a country’s gross domestic product (GDP). Countries with low GDP (below $800) generally have a high proportion of trucks and buses in their vehicle fleets. As GDP increases up to about $10,000, the share of personal automobiles increases drastically until a saturation level is reached (NRC 2003). China’s GDP has been increasing by more than 8% annually for over a decade. A large proportion of upper income people can now afford the luxury of the automobile. Kenworthy et. al. (1999) argue that, while GDP plays an important role, there are many other factors that likely influence motorization rates. By comparing cities with similar GDP and very different transportation energy use, they conclude that land use is a primary factor influencing energy use and thus motorization. Additionally demand management schemes can limit the adverse effect of motorization in China. Currently China’s regulatory structure is weak and inconsistent. Some cities have effectively provided competitive transit alternatives and limited outward expansion (Joos 2000). Others have fully embraced the automobile, pushing many other modes to the side.

Railway Terms and New Words
motorization exponential diverse migration metropolis n. adj. adj. n. n. 动力化, 摩托化 指数的, 幂数的 不同的, 变化多的 移民, 移植, 移往, 移动 大城市 Chicago, the metropolis of the Midwest.

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skyrocket fringe periphery fatality dislocation saturation

v. n. n. n. n. n.

暴涨,猛涨迅速和突然地升高或使升高: 边缘, 须边, 刘海 外围 命运决定的事物, 不幸, 灾祸, 天命 混乱, 断层, 脱臼 饱和(状态), 浸润, 浸透,饱和度 与...一致, 依照 按人口平均计算

in accordance with per capita

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Chapter 2 Rapid Transit
A rapid transit, underground, subway, elevated, or metro system is a railway system, generally in an urban area, that generally has high capacity and frequency, with large trains and total or near total grade separation from other traffic. Definitions and Nomenclature There is no single term in English that all speakers would use for all rapid transit or metro systems. This fact reflects variations not only in national and regional usage, but in what characteristics are considered essential. One definition of a metro system is as follows; an urban, electric mass transit railway system totally independent from other traffic with high service frequency. But those who prefer the American term "subway" or the British "underground" would additionally specify that the tracks and stations must be located below street level so that pedestrians and road users see the street exactly as it would be without the subway; or at least that this must be true for the most important, central parts of the system. On the contrary, those who prefer the American "rapid transit" or the newer term "metro" tend to regard this as a less important characteristic and are pleased to include systems that are completely elevated or at ground level ( at grade) as long as the other criteria are met. A rapid transit system that is generally above street level may be called an "elevated" system (often shortened to el or, in Chicago, "L" ). In some cities the word "subway" applies to the entire system, in others only to those parts that actually are underground; and analogously for "el". Germanic languages usually use names meaning "underground railway" (such as "subway" or "U-Bahn"), while many others use "metro". Train Size and Motive Power Some urban rail lines are built to the full size of main-line railways; others use smaller tunnels, limiting the size and sometimes the shape of the trains (in the London Underground the informal term tube train is commonly used). Some lines use light rail rolling stock, perhaps surface cars merely routed into a tunnel for all or part of their route. In many cities, such as London and Boston's MB-TA, lines using different types of vehicles are organized into a single unified system. Although the initial lines of what became the London Underground used steam engines, most metro trains, both now and historically, are electric multiple units, with steel wheels running on two steel rails. Power is usually supplied by means of a single live third rail (as in New York) at 600 to 750 volts, but some systems use two live rails (noticeably London) and thus eliminate the return current from the running rails. Overhead wires, allowing
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higher voltages, are more likely to be used on metro systems without much length in tunnel, as in Amsterdam; but they also exist on some that are underground, as in Madrid. Boston's Green Line trains derive power from an overhead wire, both while traveling in a tunnel in the central city and at street level in the suburban areas. Systems usually use DC power instead of AC, even if this requires large rectifiers for the power supply. DC motors were formerly more efficient for railway applications, and once a DC system is in place, converting it to AC is usually considered too large a project to contemplate. Tracks Most rapid transit systems use conventional railway tracks, though since tracks in subway tunnels are not exposed to wet weather, they are often fixed to the floor instead of resting on ballast. The rapid transit system in San Diego, California operates tracks on former railroad rights of way that were acquired by the governing entity. Another technology using rubber tires on narrow concrete or steel railways was pioneered on the Paris M6tro, and the first complete system to use it was in Montreal. Additional horizontal wheels are required for guidance, and a conventional track is often provided in case of flat tires and for switching. Advocates of this system note that it is much quieter than conventional steel-wheeled trains, and allows for greater inclines given the increased traction allowed by the rubber tires. Some cities with steep hills incorporate mountain railway technologies into their metros. The Lyon Metro includes a section of rack (cog) railway, while the Carmelit in Haifa is an underground funicular. For elevated lines, still another alternative is the monorail. Supported or "straddle" monorails, with a single rail below the train, include the Tokyo Monorail; the Schwebebahn in Wuppertal is a suspended monorail, where the train body hangs below the wheels and rail. Monorails have never gained wide acceptance except for Japan, although Seattle has a short one, which it hopes to replace with a new, larger system, and one has lately been built in Las Vegas. One of the first monorail systems in the United States was installed at Anaheim's Disneyland in 1959 and connects the amusement park to a nearby hotel. Disneyland's builder, animator and filmmaker Walt Disney, offered to build a similar system between Anaheim and Los Angeles. Crew Size and Automation Early underground trains often carried an attendant on each car to operate the doors or gales, in addition to a driver. The introduction of powered doors around 1920 permitted crew sizes to be decreased, and trains in many cities are now operated by a single person. Where the operator would not be able to see the whole side of the train to tell whether the
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doors can be safely closed, mirrors or closed-circuit TV monitors are often provided for that purpose. An alternative to human drivers became available in the 1960s, as automated systems were developed that could start a train, accelerate to the correct speed, and stop automatically at the next station, also taking into account the information that a human driver would obtain from lineside or cab signals. The first complete line to use this technology was London's Victoria Line, in 1968. In usual operation the one crew member sits in the driver's position at the front, but just closes the doors at each station; the train then starts automatically. This style of system has become widespread. A variant is seen on London's Docklands Light Railway, opened in 1987, where the "passenger service agent" (formerly "train captain") rides with the passengers instead of sitting at the front as a driver would. The same technology would have allowed trains to operate completely automatically with no crew, just as most elevators do; and as the cost of automation has decreased, this has become financially attractive. But a countervailing argument is that of possible emergency situations. A crew member on board the train may be able to prevent the emergency in the first place, drive a partly failed train to the next station, assist with an evacuation if needed, or call for the correct emergency services (police, fire, or ambulance) and help direct them. In some cities the same reasons are considered to justify a crew of two instead of one; one person drives from the front of the train, while the other operates the doors from a position farther back, and is more conveniently able to help passengers in the rear cars. The crew members may exchange roles on the reverse trip ( as in Toronto) or not (as in New York ) . Completely crewless trains are more accepted on newer systems where there are no existing crews to be removed, and especially on light rail lines. Thus the first such system was the VAL (automated light vehicle) of Lille, France, inaugurated in 1983. Additional VAL lines have been built in other cities. In Canada, the Vancouver Sky Train carries no crew members, while Toronto's Scarborough RT, opening the same year (1985) with otherwise similar trains, uses human operators. These systems generally use platform-edge doors (PEDs) , in order to improve safety and ensure passenger confidence, but this is not universal; for example, PEDs, noticeably London' s Jubilee Line Extension. the Vancouver SkyTrain does not ( And on the contrary, some lines which retain drivers, however, still use MTR of Hong Kong also uses platform screen doors, the first to install PSDs on an already operating system. ) With regard to larger trains, the Paris Metro has human drivers on most lines, but runs crewless trains on its newest line, Line 14, which opened in 1998. Singapore's North East
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MRT Line (2003) claims to be the world' s first completely automated underground urban heavy rail line. The Disneyland Resort Line of Hong Kong MTR is also automated. Tunnel Construction The construction of an underground metro is an expensive project, often carried out over many years. There are several different methods of building underground lines. In one usual method, known as cut-and-cover, the city streets are excavated and a tunnel structure strong enough to support the road above is built at the trench, which is then filled in and the roadway rebuilt. This method often involves extensive relocation of the utilities usually buried not for below city streets—especially power and telephone wiring, water and gas mains, and sewers. The structures are generally made of concrete, perhaps with structural columns of steel; in the oldest systems, brick and cast iron were used. Cut-and-cover construction can take so long that it is often necessary to build a temporary roadbed while construction is going on underneath in order to avoid closing main streets for long periods of time; in Toronto, a temporary surface on Yonge Street supported cars and streetcar tracks for several years while the Yonge subway was built. Some American cities, like Newark, Cincinnati and Rochester, were originally built around canals. When the railways took the place of canals, they were able to bury a subway in the disused canal's trench, without rerouting other utilities, or acquiring a right of way piecemeal. Another common way is to start with a vertical shaft and then dig the tunnels horizontally from there, often with a tunneling shield, thus avoiding almost any disturbance to existing streets, buildings, and utilities. But problems with ground water are more likely, and tunneling through native bedrock may require blasting. (The first city to extensively use deep tunneling was London, where a thick sedimentary layer of clay largely avoids both problems. ) The confined space in the tunnel also restricts the machinery that can be used, but specialised tunnel-boring machines are now available to overcome this challenge. One disadvantage with this, nevertheless, is that the cost of tunneling is much higher than building systems cut-and-cover, at-grade or elevated. Early tunnelling machines could not make tunnels large enough for conventional railway equipment, necessitating special low round trains, such as are still used by most of the London Underground, which cannot fix air conditioning on most of its lines because the amount of empty space between the trains and tunnel walls is so small. The deepest metro system in the world was built in St. Petersburg, Russia. In this

city, built ii the marshland, stable soil starts more than 50 meter deep. Above that level the soil is mostly made up of water-bearing finely dispersed sand. As a result of this, only three stations out of nearly 60 are built near the ground level and three more above the ground.
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Some stations and tunnels lie as deep as 100-120 meters below the surface. One advantage of deep tunnels is that they can dip in a basin-like profile between stations, without incurring significant extra costs owing to having to dig deeper. This technique, also referred to as putting stations "on humps" , allows gravity to help the trains as they accelerate from one station and brake at the next. It was used as early as 1890 on parts of the City and South London Railway, and has been used many times since.

Railway Terms and New Words
nomenclature analogous rolling stock traction countervail evacuate inaugurate excavated n. adj. n. n. v. v. vt. v. 命名法, 术语 类似的, 相似的, 可比拟的 全部车辆 牵引 补偿, 抵销 疏散, 举行就职典礼, 创新, 开辟, 举行开幕(落成、成立)典礼. 挖掘, 开凿, 挖出, 挖空

Reading Material Light Rail
Light rail or light rail transit (LRT) is a particular class of urban and suburban passenger railway that uses equipment and infrastructure that is generally less massive than that used for rapid transit systems, with modern light rail vehicles usually running along the system. Light rail is the successor term to streetcar, trolley and tram in many locales, although the term is most consistently applied to modern tram or trolley operations employing features more generally associated with metro or subway operations, including exclusive rights-of-way, multiple unit train configuration and signal control of operations. The term light rail is derived from the British English term light railway long used to distinguish tram operations from steam railway lines, and also from its usually lighter infrastructure. Light rail systems are almost universally operated by electricity delivered through overhead lines, though several systems are powered through different means, such as the JFK Airtrain, which uses a standard third rail for its electrical power, and trams in Bordeaux
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which use a special third-rail configuration in which the rail is only powered while a tram is on top of it. A few unusual systems like the River Line in New Jersey and the 0-Train in Ottawa use diesel-powered trains, though this is sometimes intended as an interim measure until the funds to install electric power become available. Definition Most rail technologies, including high-speed, freight, commuter/regional, and metro/subway are considered to be "heavy rail" in comparison. A few systems such as people movers and personal rapid transit could be considered as even "lighter", at least in terms of how many passengers are moved per vehicle and the speed at which they travel. Monorails are also considered to be a separate technology. Light rail systems can handle steeper inclines than heavy rail, and curves sharp enough to fit within street intersections. They are generally built in urban areas, providing frequent service with small, light trains or single cars. The most difficult distinction to draw is that between light rail and streetcar or tram systems. There is a significant amount of overlap between the technologies, and it is usual to classify streetcars/trams as a subtype of light rail instead of as a distinct type of transportation. The two common versions are: 1. The traditional type, where the tracks and trains run along the streets and share space with road traffic. Stops tend to be very frequent, but little effort is made to set up special stations. Because space is shared, the tracks are not usually visible. 2. A more modern variation, where the trains tend to run along their own right-of-way and are of-ten separated from road traffic. Stops are usually less frequent, and the vehicles are often got on from a platform. Tracks are highly visible, and in some cases significant effort is used to keep traffic away through the use of special signaling and even grade crossings with gate arms. At the highest degree of separation, it can be difficult to draw the line between light rail and metros, as in the case of London's Docklands Light Railway, which would likely not be considered "light" compared with London Underground. Many light rail systems have a combination of the two, with both on road and off road sections. In some countries, only the latter is described as light rail. In those places, trams running on mixed right of way are not regarded as light rail, but considered distinctly as streetcars or trams. Light rail is usually powered by electricity, generally by means of overhead wires, but sometimes by a live rail, also called third rail (a high voltage bar alongside the track) , requiring safety measures and warnings to the public not to touch it. In some cases, especially when initial funds are limited, diesel-powered versions have been used, but it is not a preferred option. Some systems, such as the JFK Airtrain in New York City, are
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automatic without a driver; however, such systems are not what is usually thought of as light rail. Automatic operation is more common in smaller people mover systems than in light rail systems, where the possibility of grade crossings and street running make driverless operation of the latter inappropriate. Advantages of light rail Light rail systems are usually cheaper to build than heavy rail, since the infrastructure does not need to be considerable, and tunnels are usually not required as most metro systems. In addition, the ability to handle sharp curves and steep gradients can reduce the amount of work required. Traditional streetcar systems and also newer light rail systems are used in many cities around the world because they generally can carry a larger number of people than any bus-based public transport system. They are also cleaner, quieter, more comfortable, and in many cases faster than buses. In an emergency, light rail trains are easier to evacuate than monorail or elevated rapid rail trains. Many modern light rail projects re-use parts of old rail networks, such as abandoned industrial rail lines. Disadvantages of light rail Like all modes of rail transport, light rail tends to be safest when operating in dedicated right-of-way with complete grade separations. Nevertheless, grade separations are not always financially or physically feasible. In California, the development of light rail systems in Los Angeles and San Jose caused a high rate of collisions between automobiles and trolleys during the 1990s. The most common cause was that many senior citizens were unfamiliar with light rail trolleys and often mistook the trolley "T" signal lights for left-turn signal lights. They would then make a left turn, right into the path of a trolley. The same high crash rate problem existed when the METRORail was first set up in Houston, Texas. To reduce such collisions, brighter lights and louder warning klaxons have been added to many at-grade crossings. However, consequently, many people do not like to live next to light rail crossings because the noise makes them impossible to sleep. A more effective means of reducing or pre venting automobile-light rail collisions has been the installation of quad crossing gates at gate crossings. These gates block both lanes of a street when the gate closes. These prevent those driving auto mobiles from driving around the gates when they are lowered. Monorail supporters like to point out that light rail trolleys are heavier per pound of cargo came than heavy rail cars or monorail cars, because they must be designed to avoid collisions with automobiles.
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Monorail
A monorail is a metro or railroad with a track consisting of a single rail (in fact a beam) , in contrast to the traditional track with two parallel rails. Monorail vehicles are wider than the beam they run on. Types and Technical Aspects There are two major types of monorail systems. In suspended monorails, the train is located under the track, suspended from above. In the more popular straddle-beam monorail, the train straddles the rail, covering it on the sides. The straddle-beam style was popularized by ALWEG. There is also a form of suspended monorail developed by SAFEGE that places the wheels inside the rail. Modern monorails are powered by electric motors and usually have tires, rather than metal wheels which are found on subway, streetcar (tram) , and light rail trains. These wheels roll along the top and sides of the rail to propel and stabilize the train. Most modern monorail systems use switches to move cars between multiple lines or permit two-way travel. Some early monorail systems— noticeably the suspended monorail of Wuppertal (Germany) , dating from 1901 and still in operation—have a design that makes it difficult to switch from one line to another. This limitation of the Wuppertal monorail is still mentioned at times in discussions of monorails in spite of the fact for both the suspended and straddle-beam type monorails the problem has been overcome. Advantages and Disadvantages The main advantage of monorails over conventional rail systems is that they require minimal space, both horizontally and vertically. The width required is determined by the monorail vehicle, not the track, and monorail systems are usually elevated, requiring only a minimal footprint for support pillars. Owing to a smaller footprint they are more attractive than conventional elevated rail lines and visually block only a minimal amount of sky. They are quieter, since modern monorails use rubber wheels on a concrete track. Monorails can climb, descend and turn faster than most conventional rail systems. Monorails are safer than many forms of at-grade transportation. As monorail wraps around its track and therefore cannot derail and unlike a light rail system, there is minimal risk of colliding with traffic or pedestrians. I hey cost less to construct and maintain, in particular when compared to underground metro systems. Monorails need their own track.
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Although a monorail's footprint is less than an elevated conventional rail system , it is larger than an underground system 's. A monorail switch by its very design will leave one track hanging in mid-air at any stated time. Unlike in the case of regular rail switches, coming from this track may cause derailing , with the additional risk of falling several meters to the ground. Most countries (except Japan) do not have standardized beam specifications for monorails, so most tend to be proprietary systems. In an emergency, passengers cannot exit at once because the monorail vehicle generally sits on top of its rail and there is no ledge or railing to stand on. They must wait until a fire engine or a cherry picker comes to the rescue. If the monorail vehicle is on fire and rapidly filling with smoke, the passengers may face an unpleasant choice between jumping to the ground (and possibly breaking bones in the process) or staying in the vehicle and risking suffocation. Newer monorail systems resolve this by building emergency walkways alongside the whole track (although this reduces the advantage of visually blocking only a minimal amount of sky) . There are also some remaining concerns over the speed and capacity of monorails.

A Brief History of Magnetic Levitation
In the early 1900s, Emile Bachelet first conceived of a magnetic suspension using repulsive forces generated by alternating currents. Bachelet's ideas for EDS remained dormant until the 1960s when superconducting magnets became available, because his concept used too much power for conventional conductors. In 1922, Hermann Kemper in Germany pioneered attractive-mode (EMS) Maglev and received a patent for magnetic levitation of trains in 1934. In 1939-43, the Germans first worked on a real train at the ATE in Goettingen. The basic design for pratical attractive-mode maglev was presented by Kemper in 1953. The Transrapid (TR01) was built in 1969. Maglev development in the U.S. began as a result of the the High-Speed Ground Transportation (HSGT) Act of 1965. This act authorized Federal funduing for HSGT projects, including rail, air cushion vehicles, and Maglev. This government largesse gave the U.S. researchers an early advantage over their foreign counterparts. Americans pioneered the concept of superconducting magnetic levitation (EDS,) and they dominated early experimental research. As early as 1963, James Powell and Gordon Danby of Brookhaven National Laboratory realized that superconductivity could get around the problems of Bachelet's earlier concepts. In 1966, Powell and Danby presented their Maglev concept of using superconducting magnets in a vehicle and discrete coils on a guideway.
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Powell and Danby were awarded a patent in 1968, and their work was eventually adopted by the Japanese for use in their system. Powell and Danby were awarded the 2000 Benjamin Franklin Medal in Engineering by the Franklin Institute for their work on EDS Maglev. In 1969, groups from Stanford, Atomics International and Sandia developed a continuous-sheet guideway (CSG) concept. In this system, the moving magnetic fields of the vehicle magnets induce currents in a continuous sheet of conducting material such as aluminum. Several groups, including MIT (Kolm and Thornton, MIT, 1972,) built 1/25th scale models and tested them at speeds up to 27 m/s (97.2 km/h.) The CSG concept is alive and well in 2001 with the Magplane. EDS systems were also being developed in the US in the early '70s, including work by Rohr, Boeing, and Carnegie-Mellon University. Maglev research in the US came to a screeching halt in 1975 when the Federal government cut off the funds to HGST research. Most Maglev systems designed and tested to date have been the EMS Maglev (also called "attractive" [as opposed to "repulsive"] because an electromagnet is "attracting" the guideway above). Examples include Transrapid, Rotem and HSST. The Japanese have been working on the Chuo Shinkansen EDS Maglev project for many years. They have built a 11.4m (18.3km) test track called the Yamanashi Maglev Test Line. Recently, the train hit 343 mph (550kmph,) a permanent "rail" record. However, there are lots of "negatives" with the Japanese system: $148 million/mile, it uses cryogenic magnets, the guideway is "active" (active systems required to make the train run, normal Japanese Shinkansen run on "passive" rails,) and the guideway is "U" shaped. Because it does not fit our definition of a Maglev Monorail, we will not cover this system in the Technical Pages. However, more information can be found online at the on the following Japanese EDS system page. Maglev 2000 of Florida is designing an EDS Maglev system. James Powell and Gordon Danby are on this team, and they were the originators of the EDS concept back in 1966. Another example of a company working on EDS Maglev is Magplane. Magplane is an evolution of work done at MIT in the early 70's by Kolm and Thornton (Scientific American, October 1973.) This system uses a "trough" guideway, but it has the advantages of a less-complex guideway system vs. the Japanese system. A White Paper is available on their website outlining this technology. Inductrack is another type of EDS system currently being developed and tested at Lawrence Livermore National Laboratory. Physicist Richard F. Post has been working on this concept for a few years, and the technology is a spinoff of work done for particle
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accelerators and payload launchers for NASA. The General Atomics team is using the Halbach concept on their Urban Maglev concept vehicle (see General Atomics papers on Maglev Monorail Technical Papers page). Permanent magnets are starting to solve a lot of the original problems with superconducting magnets and the cryogenic cooling systems: it doesn't need them!

Railway Terms and New Words
straddle suffocation proprietary alternating dormant superconducting conductor largesse in contrast to at grade cherry picker v. n. adj. adj. adj. adj. n. n. 跨骑 straddle-beam monorail 窒息 所有的, 私人拥有的 交互的 睡眠状态的, 静止的, 隐匿的 [物]超导(电)的,无电阻率的,使用无电阻物质的 导体;导线 慷慨 和...形成对比 [美]在同一水平面上 车载式吊车

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Chapter 3 RAIL TRANSIT IN NORTH AMERICA
OVERVIEW Rail transit systems in North America carry more than 5 billion passengers each year. As of 1995, a total of 53 agencies operated 207 routes of the four major rail transit modes—heavy rail, light rail, commuter rail, and automated guideway transit—with a total length of 5,100 miles (8,200 kilometers), providing 18 billion passenger-miles (29 billion passenger-kilometers) of service annually. Less common rail modes include monorails, funicular railways (inclined planes), aerial ropeways, and cable cars. Collectively, as part of public transit operations, these modes provided approximately 14.4 million annual unlinked passenger trips in 2000. Rail transit plays a vital role in five metropolitan areas, carrying over 50% of all work trips and, in three regions, over 70% of all downtown-oriented work trips. Rail transit plays an important but lesser role in another six regions. Other rail transit systems carry a smaller proportion of regional trips but fill other functions, such as defining corridors and encouraging densification and positive land-use development.

1. Heavy Rail Heavy rail transit is by far the predominant urban rail travel mode in North America, in terms of system size and utilization. Exhibit 1 illustrated the lead heavy rail transit in the United States has over the other rail modes in both annual passenger trips and annual passenger miles. Heavy rail transit is characterized by fully grade-separated rights-of-way, high level platforms, and high-speed, electric multiple-unit cars. Exhibit 1 Public Transit Ridership in the United States by Mode (2000) Modal ridership and trip lengths.

The expeditious handling of passengers is enabled through the use of long trains of up to 11 cars running frequently. Loading and unloading of passengers at stations is rapid due to level access and multiple double-stream doors. Power is generally collected from a third rail, but can also be received from overhead wires
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as in Cleveland, the Skokie Swift in Chicago, and a portion of the Blue Line in Boston. Third-rail power collection, frequent service, and high operating speeds generally necessitate the use of grade-separated pedestrian and vehicular crossings. A small number of grade crossings is an unusual feature of the Chicago system. Exhibit1 Heavy Rail Examples

Status of heavy rail systems. U.S. and Canadian heavy rail systems generally fall into two groups according to their time of initial construction. Pre-war systems are often characterized by high passenger densities and closely spaced stations, although the postwar systems in Toronto and Montréal also fall into this category. The newer U.S. systems tend to place a higher value on passenger comfort and operating speed, as expressed by less crowded trains and a more distant spacing of stations, especially in suburban areas. Newer systems also tend to provide extensive suburban park-and-ride facilities. Some overlap exists between heavy rail, light rail, and AGT. BART in the San Francisco Bay Area is a prime example of the latter category with its fast trains and provision of upholstered seats. BART station spacing outside downtown San Francisco and Oakland is great enough to allow the high overall speed required to compete with the automobile. Vancouver’s SkyTrain and Toronto’s Scarborough Rapid Transit lines are included in the heavy rail category rather than the light rail or automated guideway categories since they most closely resemble heavy rail transit systems in operating practices and right-of-way characteristics.2 2 Philadelphia’s Norristown high-speed line is another illustration of the difficulty of characterizing some rail transit modes. The Norristown line is entirely grade-separated, uses
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third rail, and has high platforms (characteristics often associated with heavy rail), but uses one-car trains, makes many stops only on demand, and has on-board fare collection (characteristics often associated with light rail). SEPTA and the FTA classify it as heavy rail. The high costs of constructing fully grade-separated rights-of-way (subway or elevated) for heavy rail transit have limited expansion in recent decades. Of the U.S. heavy rail systems, the three New York City systems carried two-thirds of all riders using this mode in 2000. Heavy rail transit’s efficiency in moving large volumes of passengers in densely populated areas is evident in this, the largest metropolitan area in the United States. Heavy rail transit plays a key role in enabling such dense urban areas to exist. In 1995, 51.9% of business day travel into Lower Manhattan was by heavy rail transit. During the 7:00 to 10:00 a.m. time period, this share increased to 62.2%. Complexity of the New York subway. The New York City subway system is one of the largest and most complex in the world. This extensive subway system carries almost twice as many riders as does the local bus system. Most lines are triple or quadruple tracked to allow the operation of express services. A large number of junctions permit trains to be operated on a variety of combinations of line segments to provide an extensive network of service. Exhibit 2 shows a diagram of the subway tracks in midtown Manhattan. Exhibit 2 MTA-NYCT Subway Tracks in Midtown Manhattan

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Exhibit 3 illustrates the peak hour and peak 15-minute passenger flow rates for the 15 busiest heavy rail transit trunk lines in the U.S. and Canada. The graph uses trunks rather than routes in order to group those services sharing tracks together. All the trunks listed are double tracked and have at least one station used by all routes. When four-track lines in New York are taken into consideration, the maximum load is a combination of the Lexington Avenue Express and Local at 63,200 passengers per peak hour direction, with almost comparable volumes on the combined Queens Boulevard lines at Queens Plaza. In comparison, the busiest two-track heavy rail line in the world is in Hong Kong, with 84,000 passengers per peak hour direction. Exhibit 3 Peak Hour and Peak 15-minute Flows for the Busiest 15 U.S. and Canadian Heavy Rail Transit Trunk Lines (1995)(R25)

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2. Light Rail Transit Light rail transit, often known simply as LRT, began as a development of the streetcar to allow higher speeds and increased capacity. Light rail transit is characterized by its versatility of operation, as it can operate separated from other traffic below grade, at-grade, or on an elevated structure, or can operate together with motor vehicles on the surface (Exhibit 4). Service can be operated with single cars or multiple-car trains. Electric traction power is obtained from an overhead wire, thus eliminating the restrictions imposed by having a live third-rail at ground level. This flexibility helps to keep construction costs low and explains the popularity this mode has experienced since 1978 when the first of 14 new North American light rail transit systems was opened in Edmonton. These newer LRT systems have adopted a much higher level of segregation from other traffic than earlier systems enjoyed. A recent trend is the introduction of diesel light rail cars by European manufacturers. Trials of such cars have generated considerable interest in some areas, given the ease with which diesel light rail service can be established on existing rail lines. Ottawa opened a 5-mile (8-km) line connecting two busway stations in 2002. New Jersey Transit is constructing a diesel light rail line between Trenton and Camden, scheduled to open in 2003. It should be noted that the TRB Committee on Light Rail Transit’s definition of light rail encompasses only electric-powered lines, and therefore would not consider diesel light rail to be “light rail transit.” However, the TCQSM’s capacity procedures are based primarily on right-of-way type and secondarily by mode. The basic light rail capacity procedures can be applied to diesel light rail, but differences in vehicle operating characteristics (such as acceleration) would need to be taken into account. Three major types of light rail operations exist: ? Light rail, with relatively frequent service along mostly exclusive or segregated rights-of-way, using articulated cars and up to four-car trains.
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? Streetcars, operating along mostly shared or segregated rights-of-way, with one-car (or rarely, two-car) trains. Vehicle types and ages can vary greatly. ? Vintage trolleys provide mainly tourist- or shopper-oriented service, often at relatively low frequencies, using either historic vehicles or newer vehicles designed to look like historic vehicles.

Exhibit 4 Light Rail Examples

As of 2002, there are 27 light rail and streetcar systems and 5 vintage trolley systems operated by public transit agencies in North America. An additional three light rail, one streetcar, and one vintage trolley systems will open by 2004. Light rail passenger volumes. Exhibit 5 gives typical peak hour peak direction passenger volumes, service frequencies, and train lengths for principal U.S. and Canadian light rail transit lines. Exhibit6 provides an indication of the maximum peak passenger volumes carried on a number of light rail systems for which data are available. The exhibit illustrates the peak passenger volumes carried over the busiest segment of the LRT system; in many cases, this represents passengers being carried on more than one route.
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Some streetcar and light rail lines carried substantially higher passenger flows in the peak years of 1946-1960. Post-World War II streetcars operated at as close as 30-second headways both on-street (Pittsburgh) and in tunnels (Philadelphia). Peak hour passenger flows were approximately 9,000 persons per hour. San Francisco’s Market Street surface routes carried 4,900 peak hour one-way passengers per hour before they were placed underground. Now, the observed number of peak hour passengers at the maximum load point usually reflects demand rather than capacity. Peak 15-minute volumes expressed as hourly flow rates are about 15% higher. Exhibit 5 Observed U.S. and Canadian LRT Passenger Volumes: Peak Hour at the Peak Point for Selected Lines (1993-96 Data)

NOTE: In a single hour a route may have different lengths of trains and/or trains with cars of different lengths or seating configurations. Data represent the average car. In calculating the passengers per foot of car length, the car length is reduced by 9% to allow for space lost to driver cabs, stairwells, and other equipment. Data were not available for the heavily used Muni Metro subway in San Francisco. Exhibit 6 Peak Hour and Peak 15-Minute Directional Flows for Selected U.S. and Canadian Light Rail Transit Trunks (1995)

3. Automated Guideway Transit (AGT) As their name indicates, AGT systems (Exhibit 7) are completely automated (vehicles without drivers), with personnel limited to a supervisory role. Their automated nature requires guideways to be fully separated from other traffic. Cars are generally small and service is frequent—the name “people mover” is often applied to these systems, which can take on the
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role of horizontal elevators. The technologies used vary widely and include rubber-tired electrically propelled vehicles, monorails, and cable-hauled vehicles. AGT status. Nearly 40 AGT systems are operated in the United States today, with none operating in Canada. The SkyTrain in Vancouver and the Scarborough RT in Toronto, while automated and sharing the same basic technology that is used on the Detroit People Mover, have more in common with heavy rail systems than AGT lines in their service characteristics, ridership patterns, and operating practices, and so are included in the heavy rail listings. AGT systems operate in four types of environments: ? Airports; ? Institutions (universities, shopping malls, government buildings); ? Leisure and amusement parks (e.g., Disneyland); and ? Public transit systems. Most of these systems are operated by airports or by private entities, especially as amusement park circulation systems. Exhibit 7 Automated Guideway Transit Examples

AGT transit services. There are three public transit AGT systems operating in the United States, serving the downtown areas of Detroit, Jacksonville, and Miami. The Detroit People Mover line has remained unchanged from its opening in 1987, while the Miami MetroMover added two extensions in 1994. Jacksonville opened the first 0.7-mile (1.1-kilometer) section of its Skyway in 1989, with new extensions opening from 1997 to 1999 to serve both sides of the St. Johns River. A relatively large institutional system is the one at the West Virginia University campus in
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Morgantown. This 3-mile (5-kilometer) line features off-line stations that enable close headways, down to 15 seconds, and permit cars to bypass intermediate stations. The cars are small, accommodating only 21 passengers, and are operated singly. On-demand service is possible during off-peak hours. Exhibit 8 lists ridership and other statistics for the North American AGT systems used for public transit. Exhibit 8 North American AGT Systems Used for Public Transit (2000)

Daily ridership data for other North American AGT systems are shown in Exhibit 9. Caution should be exercised with many of these figures, as the non-transit systems are not required to provide the reporting accuracy mandated by the FTA. Ridership on many systems is also likely affected by seasonal patterns and less pronounced peaking (with the notable exception of airport systems) than occurs on transit systems. Regardless of these qualifications, the total daily ridership on the 36 non-transit systems amounts to over 500,000, compared to about 20,000 on the three transit AGT lines. Exhibit 9 U.S. Non-Transit AGT Systems (2003)

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4. Monorail Although often thought of as being relatively modern technology, monorails (Exhibit 10) have existed for over 100 years, with the first monorail, in Wuppertal, Germany, having opened in 1901. Vehicles typically straddle or are suspended from a single rail. Driverless monorails fall into the category of AGT, and include the systems identified as monorails in Exhibit 9, plus the Jacksonville Skyway. Monorails that use drivers are by definition not automated, and thus form their own category. For the purposes of determining capacity, monorails can use the grade-separated rail procedures, with appropriate adjustments for the technology’s particular performance characteristics. The 0.9-mile (1.5-kilometer) Seattle Center monorail, originally constructed for the 1962 World’s Fair, is the only existing U.S. example of a non-automated public transit monorail. It carried approximately 6,100 passengers a day in 1999. About 1 dozen privately operated monorails are in use at North American zoos and amusement parks. Outside the United States, several monorails are used for public transit service similar to an elevated heavy rail line. Examples include the Wuppertal Germany monorail, seven systems in Japan, and a downtown circulator in Sydney, Australia. Exhibit 2-10 Monorail Examples

Funiculars, Inclines, and Elevators Funicular railways, also known as inclined planes or simply inclines, are among the oldest successful forms of mechanized urban transport in the United States, with the first example, Pittsburgh’s Monongahela Incline, opening in 1870 (and still in operation today). Funiculars are well suited for hilly areas, where most other transportation modes would be unable to operate, or at best would require circuitous routings. The steepest funicular in North America operates on a 100% (45°) slope, and a few international funiculars have even steeper grades. Early funiculars were used to transport railroad cars and canal boats in rural areas, as well as to provide access to logging areas, mines, and other industrial sites. Funiculars have played a role in many transit systems, moving not just people, but cars, trucks, and streetcars up and down steep hillsides. An example of a remaining vehicle-carrying incline that is part of a transit system is in Johnstown, Pennsylvania. Nearby, in Pittsburgh, the Port Authority owns the 2 remaining inclines from a total of more than 15 that once graced the hilly locale. Inclined plane status. The number of remaining inclined planes in North America is small, but they are used extensively in other parts of the world to carry people up and down hillsides in both urban and rural environments. Switzerland alone has over 50 funiculars, including urban funiculars in Zürich and Lausanne. Many other cities worldwide have funiculars, including Barcelona, Budapest, Haifa, Heidelberg, Hong Kong, Paris, Prague, and Valparaíso, Chile (which has 15).
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Many of these systems are less than 30 years old or have been completely rebuilt in recent years. In addition, funiculars are still being built for access to industrial plants, particularly dams and hydroelectric power plants, and occasionally, ski resorts. New funiculars, primarily in Europe, also provide subway or metro station access. New designs rarely handle vehicles and make use of hauling equipment and controls derived from elevators. The person capacity of older inclined planes is modest, but modern designs can carry large numbers of people. Capacity is a function of length, number of intermediate stations (if any), number of cars (one or two), and speed. Person capacity is usually modest—on the order of a few hundred passengers per hour. However, high-speed, large-capacity funiculars are in use, and a new facility, designed for metro station access in Istanbul, has a planned capacity of 7,500 passengers per direction per hour. Most typical design involves two cars counterbalancing each other, connected by a fixed cable, using either a single railway-type track with a passing siding in the middle or double tracks. Single-track inclined elevators have just one car and often do not use railway track—see, for example, the Ketchikan example in Exhibit 11(e). When passing sidings are used, the cars are equipped with steel wheels with double flanges on one set of outer wheels per car, forcing the car to always take one side of the passing siding without the need for switch movement. Earlier designs used a second emergency cable, but this is now replaced by automatic brakes, derived from elevator technology, that grasp the running rails when any excess speed is detected. Passenger compartments can either be level, with one end supported by a truss, or sloped, with passenger seating areas arranged in tiers. To minimize wear-and-tear on the cable, and make the design mechanically simpler, an ideal funicular alignment is a straight line, with no horizontal or vertical curves. To achieve this design, a combination of viaducts, cuttings, and/or tunnels may be required, as illustrated in Exhibit 11(c). However, many funiculars have curved alignments. Public elevators, as shown in Exhibit 11(f), are occasionally used to provide pedestrian movement up and down steep hillsides where insufficient pedestrian volumes exist to justify other modes. These elevators allow pedestrians to bypass stairs or long, out-of-direction routes to the top or bottom of the hill. Exhibit 11 provides statistics for North American funiculars.

Exhibit 11 Funicular and Elevator Examples

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Exhibit 12 U.S. and Canadian Funiculars and Public Elevators (2001)

5. Aerial Ropeways 缆车 Aerial ropeways (Exhibit 13) encompass a number of modes that transport people or freight in a carrier suspended from an aerial rope (wire cable). The carrier consists of the following components: ? A device for supporting the carrier from the rope: either a carriage consisting of two or
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more wheels mounted on a frame that runs along the rope, or a fixed or detachable grip that clamps onto the rope; ? A unit for transporting persons or freight: an enclosed cabin, a partially or fully enclosed gondola, or an open or partially enclosed chair; and ? A hanger to connect the other two pieces. The rope may serve to both suspend and haul the carrier (monocable); or two ropes may be used: a fixed track rope for suspension and a moving haul rope for propulsion (bicable); or multiple ropes may be used to provide greater wind stability. Carriers can operate singly back-and-forth, or as part of a two-carrier shuttle operation, or as part of a multiple-carrier continuously circulating system. The common aerial ropeway modes are the following: ? Aerial tramways, which are suspended by a carriage from a stationary track rope, and propelled by a separate haul rope. Tramways have one or, more commonly, two relatively large (20 to 180 passenger) cabins that move back and forth between two stations. Passenger loading occurs while the carrier is stopped in the station. ? Detachable-grip aerial lifts, consisting of a large number of relatively small (6 to 15 passenger) gondolas4 or 2 to 8 passenger chairs that travel around a continuously circulating ropeway. The carriers move at higher speeds along the line, but detach from the line at stations to slow to a creep speed (typically 0.8 ft/s or 0.25 m/s) for passenger loading. ? Fixed-grip aerial lifts, which are similar to detachable-grip lifts, with the important exception that the carriers remain attached to the rope through stations. Passenger loading and unloading either occurs at the ropeway line speed (typical for ski lifts), or by slowing or stopping the rope when a carrier arrives in a station (typical for gondolas). Some fixed-grip gondolas are designed as pulse systems, where several carriers are attached to the rope in close sequence. This allows the rope to be slowed or stopped fewer times, as several carriers can be loaded or unloaded simultaneously in stations. ? Funitels are a relatively new variation of detachable-grip aerial lifts, with the cabin suspended by two hangers from two haul ropes, allowing for longer spans between towers and improved operations during windy conditions. Exhibit 13 Aerial Ropeway Examples

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Aerial ropeways are most often associated with ski areas, but are also used to carry passengers across obstacles such as rivers or narrow canyons, and as aerial rides over zoos and amusement parks. A few are used for public transportation. The Roosevelt Island aerial tramway in New York City, connecting the island to Manhattan, carries approximately 3,000 people each weekday. A gondola system in Telluride, Colorado, transports residents, skiers, and employees between the historic section of Telluride, nearby ski runs, and the Mountain Village resort area, reducing automobile trips between the two communities and the air pollution that forms in the communities’ box canyons. In 2006, the Delaware River Port Authority plans to complete a detachable-grip gondola across the river between Philadelphia and Camden, primarily to serve tourists visiting attractions on both sides of the river. Finally, several North American ski areas use aerial ropeways for site access from remote parking areas, as an alternative to shuttle buses. Aerial ropeway alignments are typically straight lines, but allow changes in grade (vertical curves) over the route. Intermediate stations are most often used when a change in horizontal alignment is required, resulting in two or more separate ropeway segments—detachable-grip carriers can be shuttled between each segment, but passengers must disembark from other types of carriers and walk within the station to the loading area for the next segment. Gondola systems and chair lifts can also have changes in horizontal alignment without intermediate stations, but this kind of arrangement is much more mechanically complex and is rarely used. Exhibit 14 lists aerial tramway, detachable-grip gondola, and funitel systems in use in North America, along with their main function and technical data. Exhibit 14 U.S. and Canadian Aerial Ropeways (2002)

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6. Cable Cars Cable cars (Exhibit 15) now operate only in San Francisco, where the first line opened in 1873.5 Although associated with San Francisco’s steep hills, more than two dozen other U.S. cities, including relatively flat cities such as Chicago and New York, briefly employed this transit mode as a faster, more economical alternative to the horse-drawn streetcar. Most cable lines were converted to electric streetcar lines between 1895 and 1906 due to lower operating costs and greater reliability, but lines in San Francisco, Seattle, and Tacoma that were too steep for streetcars continued well into the 20th century. Three cable car routes remain in San Francisco as a National Historic Landmark and carried 9.2 million riders in 2000. The cars are pulled along by continuous underground cables (wire ropes) that move at a constant speed of 9 mph (15 km/h). A grip mechanism on the car is lowered into a slot between the tracks to grab onto the cable and propel the car.picture?The grip is released from the cable as needed for passenger stops, curves, and locations where other cables cross over the line. Cable car systems are not very efficient, as 55 to 75% of the energy used is lost to friction. However, cars can stop and start as needed, more-or-less independently of the other cars on the system, and a large number of cars can be carried by a small number of ropes. The Chicago City Railway operated around 300 cars during rush hours on its State Street line in 1892, which comprised four separate rope sections totaling 8.7 miles (13.9 km) in length. Modern automated people movers (APMs) that use cable propulsion have retained many of the original cable car technological concepts, albeit in an improved form. Modern cable-hauled APMs often include gripping mechanisms and, in some cases, turntables at the end of the line. Some of these APMs can be accelerated to line speed out of each station, in a similar manner as detachable-grip aerial ropeways. Once at line speed, a grip on these APMs attaches to the haul rope, and the vehicle is moved at relatively high speed along the line. At the approach to the next station, the vehicle detaches from the rope, and mechanical systems brake the vehicle into the station. This technology addresses two of the major issues with the original cable cars: (1) having only two speeds, stop and line speed (up to 14 mph or 22 km/h), which caused jerky, uncomfortable acceleration for passengers and (2) rope wear each time cars gripped the cable, as the cable slid briefly through the slower moving grip before the grip took hold and caught up to the cable’s speed. The airport shuttle at the Cincinnati-Northern Kentucky Airport is an example of a detachable-grip APM, while the Mystic Transit Center APM (Exhibit 15b) is an example of an APM with a permanently attached cable. Other examples were listed in Exhibit 7. Exhibit 15 Cable Car Examples

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Reading material Exclusive Right-of-Way The right-of-way is reserved for the exclusive use of transit vehicles. There is no interaction with other vehicle types. Intersections with other modes are grade-separated to avoid the potential for conflict. Exclusive rights-of-way provide maximum capacity and the fastest and most reliable service, although at higher capital costs than other right-of-way types. Automated guideway transit systems must operate on this type of right-of-way, as their automated operation precludes any mixing with other modes. This right-of-way type is most common for heavy rail systems and many commuter rail systems, and occurs on at least portions of many light rail systems. Segregated Right-of-Way Segregated rights-of-way provide many of the same benefits of exclusive rights-of-way but permit other modes to cross the right-of-way at defined locations such as grade crossings. Segregated rights-of-way are most commonly employed with commuter rail and light rail transit systems. The use of this right-of-way type for heavy rail transit systems has largely been eliminated. Shared Right-of-Way A shared right-of-way permits other traffic to mix with rail transit vehicles, as is the case with streetcar lines. While this right-of-way type is the least capital intensive, it does not provide the benefits in capacity, operating speed, and reliability that are provided by the other right-of-way types.

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Lesson Ten

Chapter 4 The Railroad Track
The railroad has a raised track for its cars and engines and the wheels of these railroad vehicles have flanges on inner side to keep them on this track. The engineer in control of a locomotive drawing a train over a railroad track does not steer his vehicle as the driver of a highway motor vehicle must do. Railroad trains cannot meet and pass one another at any point of the road over which they travel. They must keep to their tracks. Some railroads are built with two or more tracks, and on each track the trains all usually move in the same direction. Multiple tracks simplify the problem of meeting and passing. If a railroad has a single main track, it must have turn-outs or passing sidings at intervals, where trains may leave the main track temporarily and wait for other trains to pass. The most common type of railroad track consists of two parallel lines of heavy steel rails, securely fastened to wooden cross-ties placed in a bed of rock or gravel ballast. The distance between the rails is called the gauge of the railroad. The standard gauge of the railroads in many countries is 1,435 meters. A uniform railroad gauge makes it possible for a person to travel over several railroads without changing cars, when the gauges were different it was necessary for freight or passengers to be transferred from one car to another at all points where there was a change of gauge. The adoption of a uniform gauge effected a great saving in the time and in the expense of transporting both passengers and freight. Railroad rails are long heavy bars of steel such shape that the end or cross-section of a rail looks something like the letter T. The rails are called T-rails because of this shape. The heavy top part of rail, on which the wheels of cars and engines run, is called the head; the flat part, which rests on the cross-tie, is the base; while the thin part between the base and head is called the web. Rails differ greatly in design and weight, according to the kind of traffic they must support when placed in the track. Most of the rails now manufactured are 25 meters long, and vary in weight form 33 to 60 kilogrammes to the metre. The largest and heaviest rails are to be found in the main line tracks of the railroads, which carry the largest volume of freight and passenger traffic. Railroad rails are fastened to the cross-ties with heavy steel spikes. The most common type of spike is the cut spike, made of tough steel, with a wedge-shaped point that permits it to be driven into the tie with a heavy spike maul, and with a hooked head which fits over the edge of the rail base and holds the rail fast to the tie. Another type of spike, which does not bruise and tear the fibres of the tie and thereby lead to decay, is the screw spike, made much like a large screw, with a flanged head that fits over the edge of the rail base. Where
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screw spikes are used, holes are bored into the ties, and the spikes forced into the holes with wrenches. Screw spikes, when first insert, hold rails more firmly in place than the ordinary cut spikes. A type of spike newer than the screw spike is an elastic or compression spring spike. It is made of spring steel, and resembles the ordinary cut spike except that instead of having the conventional hooked head, it has a goose-necked head. When driven into the tie, this head exerts a spring pressure upon the base of the rail, holding it and the tie plate firmly in position with a force which the cut spike and screw spike do not have. Where the ends of the rails meet in the track, they are held together with splice bars or joint bars, heavy plates of steel, which fit closely to the web and base of the rail on both sides, and are fastened together with large steel bolts passing through holes in the web of the rails. There are several types of rail joints, all of them designed for strength and stiffness, to hold up the weight of passing trains and keep the ends of the rails from breaking and wearing out. Rail joints cannot be made entirely stiff, and even with the strongest joints the ends of the rails give a little as trains pass over. As you stand by a moving train, or even when you are riding in a passenger car, you can hear the sharp, regular "click-click, click-click" made by the wheels as they move over the rail joints. The pounding of the wheels causes the ends of the rails to become battered and to split as time passes. Nearly all rails wear out first at the ends; the rail joint is the weakest part of the track. When rails are placed in the track, it is customary not to lay the ends of adjacent rails closely together. Like any other piece of iron or steel, a railroad rail expands and gets a bit longer when it becomes hot, and contracts and gets shorter when it is cold. If not held firmly in place, 12-metre rail will change more than a centimetre in length with a change of temperature of 140 degrees. If you look at a railroad track on a hot summer day, you will probably see that the ends of the rails fit snugly together. On a cold day in winter the ends are a small distance apart. It was formerly necessary for railroad builders, when they were laying track, to make allowance for the expansion and contraction of the rails, because they were not held to the ties firmly enough to prevent their lengthening and shortening with the change of temperature between winter and summer. Modern methods of track building are such that rails can be held in place and the force of internal expansion and contraction almost entirely overcomes. A few railroads have been experimenting in recent years with rails much longer than the standard 25 metres. The rails of standard length have been welded together to make rails several hundred metres in length. A continuous rail 3,600 metres in length has been laid in some railroads. The welding is done by electricity, by an oxyacetylene process or by the use of thermit, which consists of mixture of iron oxide and aluminum. It has been demonstrated quite satisfactorily that
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proper fastening of the rails to the ties can solve the problem of expansion and contraction, and there is no danger that the track will buckle, as it might do if the rails were not firmly held in place. Though still in the experimental stage, the continuous rail may become common upon railroads. The elimination of the track joints reduces the cost of track repair and maintenances, the continuous rails last longer than the shorter rails, and they give better riding qualities to the track. The ties of the railroad track are not laid upon the soft earth of the road-bed, but rest upon a bed of crushed rock or gravel, which is called ballast. On rainy days the ballast lets the water drain away quickly without weakening or washing away any of the track. In the winter time water cannot collect in the ballast and freeze. Any poorly drained highway will "heave" in the springtime, under alternate freezing and thawing, and the railroad is no exception. Good drainage is the first requisite of a good highway; it is the ballast in the railroad which helps provide needed drainage. Ballast is also necessary to keep the railroad track at the proper lever and in correct line. Everybody has seen section gangs surfacing tracks in the summer time, working the ballast with shovels and picks. Crushed rock is the best kind of ballast because it lasts long, it is not dusty, it lets water drain away freely, and it affords the best support for the track. Next to crushed rock, gravel is the most common material used for ballast.

Railway Terms and New Words
flnge steer turn-out(turnout) interval gravel n. v. n. n. n. 轮缘,凸缘,法兰 驾驶,掌握方向 岔道,岔线,待避线(turnout track) 间隔,空隙 at intervals 每隔一个间隔 砾石;v. 铺石子 道渣,引伸为道床

ballast n. a bed of rock or gravel ballast transfer cross-section web base spike cut spike wedge maul wrench v n n. n. n. n. n. n. n.

岩石或砾石道床 中转,换乘 横断面 轨腰 轨底 道 钉 钩头 道钉 楔子,楔形物 大槌 扳手,钳子

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splice n. 联接 splice bar 鱼尾板,联接板,夹板 snug n. 恰好的,密切的 acetylene n. 乙炔 oxy-~ process 氧乙炔法 thermit n. 铝热剂 thaw v. 融化,溶化 a single track 单线 double tracks 双线 multiple tracks 复线 meet and pass 交会与越行(会让) ; passing station 会让站 passing sidings 会让线,越行线,侧线 cross-tie 枕木(tie, sleeper) wooden ~ 木枕 concrete ~ 混凝土枕 Consist of = to be made up of 由……组成; To make allowance for = take … into consideration 考虑到,估计到; e.g.:It will take thirty minutes to get to the station, making allowance for traffic delays. Instesd of + (gerund): (做……)而不做…… e.g.:You should be out instead of sitting in on such a fine day. To keep/prevent/protect … from + (gerund):防止(阻止)……发生 e.g.:to keep the ends of rails from breaking and wearing out. In place :适当地,切合地; To last long:耐久,持久,持续长时间; In combination with:与……相结合;

Reading Material
Function of the Track
Track has three main functions. It must support the load, provide a smooth surface for easy movement and guide the wheels of the train. The railroad line should be as level and straight as can be achieved, because grades and curves increase the burden on the locomotive and the wear on the track. The tractive effort required to pull a load up a 1% grade is about five times what is required on straight level track and a curvature of 1 degree requires an increase of from 12.5% to 25% in tractive effort. Road-bed is the subgrade on which are laid the ballast, ties and rails. There are two types of it-cut and fill. It should be firm, well drained and of adequate dimensions. Steel rails support the load which locomotives and cars impose on the track. Ties support the rails and ballast supports the ties. Today, rail weighing as much as 60 kilogrammes or more to the metre is in use on lines handling heavy traffic. The use of the
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so-called T-rail (from its shape) has persisted because experience has shown it is the most practical and economic form of rail. The ties keep the rails the proper distance apart, support them and transmit the load to the ballast cushion beneath. With modern methods of chemical treatment, the service life of ties has been approximately trebled, from less than 10 years to more than 20 years, on the average. For the saving of timber and other reasons, concrete ties have developed so rapidly that concrete is now considered to be the ideal material for railway ties. To reduce mechanical wear from impact of loads transmitted through the rail, metal tie plates are inserted between the rail and the tie. These plates spread the rail burden over a wide tie area, and thus help to protect the tie from the cutting and wearing effect of the rail base. Wheel friction causes a tendency for rails “to creep” longitudinally, especially on each track. Small anchors, or anticreepers, applied to the rail and bearing against the edge of the tie are used to check this movement. Ballast, usually of crushed rock, cinder, gravel or mine waste, supports and cushions the ties and helps to keep them in proper position as well as to distribute the track load over the road-bed .It also facilitates drainage, thereby promoting firmness and smooth riding qualities of track. As a train enters a curve, its natural tendency is to continue going straight ahead. It turns only because the outside rail forces it to do so. To permit trains to traverse curves with safety and greater smoothness, the outer rail is super-elevated, or raised above the height of the inner rail so as to balance the forces set up when the movement of the train is diverted from a straight line by the rails of a curve. The right amount of superelevation for a given curve depends on the train speeds.

Railway Terms and New Words
grade and curve gradient and curvature tractive effort (force) fill and cut subgrade, roadbed metal tie plate bear against anti-creeper 坡段(斜坡)和曲线 坡度(斜率)和曲度(曲率) 牵引力 路堤和路堑(填方和挖方) 路基 轨底板 靠(压)在……上,紧靠 防爬器 anchor 制动器

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Chapter 5 General Vehicle Description
The trains running on Shanghai Metro Line 1 and Line 2 are all made in Germany. There are three types of cars: l Type A is a trailer car with a cab, a length over couplers of ≤24,400 mm and a tare weight of 33t. l Type B is a motor car with pantograph, a length over couplers of 22,800mm and a tare weight of 36t. l Type C is a motor car with air compressor, a length over couplers of 22,800mm and a tare weight of 36t. The carbody of the Shanghai Metro cars is of a lightweight construction made of large aluminum alloy extrusion profiles. Each car has five pocket sliding doors per car side. The passenger compartments of the cars are connected together by gangways. Fiberglass seat benches are arranged longitudinally between the doors, thus also creating ample standing accommodation. Each car is equipped with two roof-mounted air conditioning units. The cars are each provided with two bogies. The cars are equipped with a compressed-air supply system to operate the pantographs, the doors, the air-conditioning system, the horn, the windshield wipers, the secondary suspension components and the brakes. The B-cars and C-cars of one unit are connected by means of a semi-permanent drawbar. Motor cars are coupled to trailer cars via semi-automatic couplers. Semi-automatic couplers are also used to connect different units. There is an automatic coupler at each train end (see Fig.2). The basic vehicle trainset arrangement consists of two units combined to form a 6-car train. A 3-car unit for a 6-car trainset comprises two motor cars (B-car and C-car) and one trailer car (A-car). The electrical concept of the vehicle may be divided into the high-voltage power supply, the auxiliary power supply including battery supply and the earthing concept. High-voltage Power Supply: The traction equipment, the auxiliary inverter and, as a special case, the air compressor are directly fed by the 1500V DC line current. The traction inverters of the traction equipment supply the necessary three-phrase current for the traction motors. Each traction inverter is protected by the high-speed circuit breaker. Auxiliary Power Supply: To supply the various kinds of electrical equipment on the vehicle, there are three voltage levels provided:
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l DC voltage of 110V l AC voltage of 220V l Three-phase voltage of 380V±5%, 50 Hz±1% The three-phase voltage is supplied by auxiliary inverter (A- car, B- car and C-car) which can be fed with power by the 1500V DC line supply or by the workshop-supply. The 220V voltage for single-phase AC loads is also fed with power by the A-car inverter. The DC level of 110V is supplied by the battery chargers incorporated in A-car inverters or the batteries (A-car). The following single phase AC loads are supplied by the auxiliary inverters of the A-cars: l Passenger compartment lighting (220V) l Cab heating l Windscreen heating (220V) l Socket outlets (one 220V socket outlet per car) Three-phase loads include: ? Compressors of air conditioning system ? Condenser blower ? Evaporator blower ? Traction container blower and braking resistor blower The DC-level is divided into an electronic power supply (important loads) and a normal power supply. If the battery drops below a limit value, the battery main contactor is opened and the normal DC power supply is disconnected from the battery. When the battery voltage rises above the limit value, the normal power supply is automatically switched back on line. The following loads are connected to the normal DC power supply: ? Cab lighting ? Emergency lighting ? Control of air conditioning system and emergency ventilation ? Door control ? Auxiliaries ? Train control ? Radio ? Control of air compressor ? Head and tail lights The following are connected to the electronic power supply: ? All brake electronic control units (BECU)
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? All traction control units (TCU) ? Control of the auxiliary inverters ? Central control unit (CCU) and SIBAS KLIP stations ? ATC system ? Public address system ? Display Earthing concept The earthing of the Shanghai Metro Line 2 is required mainly to ensure effective EMC, operational earthing and protective earhting: ? EMC -(electromagnetic compatibility) measures protect the electronic equipment in the vehicle and the trackside signaling equipment against interference from high-frequency pulsating currents produced in the vehicle. This interference can lead to failure of the vehicle and to disturbance of radio traffic and of service on the track. ? Operational earthing serves to provide a negative return for the line current via the track (traction earth). ? Protective earthing provides protection for persons and equipment against high touch voltages in the case of faults. Braking Systems The brake equipment of the train consists of two different braking systems: ? ED-braking system (electrodynamic brakes) ?P/AP-braking system (P=pneumatic, AP=active and passive control) The electric traction equipment of the train permits the use of an electrodynamic braking system that consists of completely independent dynamic brakes per motor car. Each brake is controlled steplessly by the traction control unit (TCU) installed in the motor cars. The energy generated during braking is fed back into the overhead line as far as possible. Surplus energy is dissipated in the brake resistor. The pneumatic braking system can be controlled actively or passively. For active control, compressed air is used to press the brake pads against the wheel with the help of a cylinder and a caliper. For passive control, the pads are applied by spring force, i.e. air pressure is not present in the brake cylinder. The active and passive brake circuits are separate from each other and cannot act simultaneously, thus preventing overbraking. The active pneumatic brake is controlled steplessly by the electronic brake control unit (BECU) installed in each car. The passive pneumatic brake is applied with full force either when the parking brake valve is de-energized or when no compressed air is applied to the pads.

A train diagnostic system is provided for each 3-car unit. The Shanghai Metro trains
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are equipped with an automatic train control (ATC) system which comprises automatic train protection (ATP), automatic train operation (ATO) and automatic train supervision ATS) from the line. ATP supervises the actual speed and the distance from other trains. On detecting a dangerous operating state, ATP performs emergency braking up until train standstill. ATO ensures automatic train operation except for the “start” order.

Railway Terms and New Words
cab coupler tare tare weight pantograph ] compressor air compressor extrusion profile gangway fiberglass longitudinally accommodation n. n. n. n. ad. n. n. n. 压缩机 空压机 挤压 型材 过道,通道 玻璃纤维(钢板) 纵长(轴向)地 容纳,座位 转向架 n. n. n. 司机室 车钩,联轴节 皮重 空车自重 受电弓

bogie n. windshield n. =wind-screen wiper suspension traction inverter phase incorporate n. n. n. n. n. v.

风挡,挡风玻璃 刮雨器,刮水器 悬挂 牵引 逆变器 相 包含(有), (安)装有

windscreen =windshield n. socket outlet socket outlet condenser evaporator ventilation n. n. n.
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风挡,挡风玻璃 插座,插口 出口,电源 电气插座 冷凝器 蒸发器 通风 插座,

n. n.

Lesson Eleven

compatibility interference pulsat pulsating disturbance negative electrodynamic steplessly surplus dissipate caliper simultaneously diagnostic standstill

n. n. v. a. n. a. a. ad. n. vt. n. ad . a. n.

相容型,兼容性 干涉,干扰 脉动,脉冲 脉冲的 干扰,扰动,破坏 否定的,反对的,带负电的 电动的 无级的 过剩 ,剩余 使…消失,驱散 卡钳,测径器 同时发生地 诊断的 停止,停顿,静止

Reading Material
Passenger Rolling Stock
We have now to consider the development in the design and construction of passenger rolling stock. The earliest coaches, of which the design was based on that of the road stage-coaches, were all four-wheel vehicles. By degrees the desirability of longer vehicles became recognized,so that six-wheel coaches came into use,and then eight-wheel. Of the last-mentioned the earlier examples, like their predecessors, had rigid wheel-bases; but the greatest of all advances in chassis design came with the introduction of the bogie coach, which is now standard practice all over the world. As with the locomotive bogie,the coach bogie is a four wheel or six-wheel truck,supporting the coach-end through the medium of a pivot, and with freedom to swing. Not only do the bogies permit the coaches to adjust themselves smoothly and easily to the curves,but with the aid of carefully designed springing they help to damp down the vibrations resulting from rapid movement along the track before these vibrations reach the coach-body. In Great Britain the length of coaches continues steadily to increase, with the aim of providing more accommodation relatively to tare weight, but this purpose to some extent is nullified by the increased space now given to passengers. The provision of corridors,for example,cut the number of seats abreast in third-class compartments down from five to
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four, and the more recent introduction of intermediate arm-rests in second-class stock like those in the first-class,from four to three. More spacious lavatories at both ends of each corridor coach, and transverse center vestibules for more rapid entry and exit,all combine to take up valuable space. From lengths of 54 to 60ft. in the days before nationalization, standard British corridor coaches have now increased in length to 63 ft. 6 in. over bodies and 67ft.0 in. over buffers. For some years the former Great Western Railway specialized in 70ft.stock, which,with lavatories at both ends,in a third-class coach permitted ten compartments seating 80 passengers; the present standard seconds have eight compartments and , due to the introduction of arm-rests, seat 48 passengers only - a considerable reduction in seating accommodation relatively to tare weight. In the United States all the modern streamline coaches are 85 ft. long. In general,restaurant and sleeping-cars have been built to a greater length than ordinary corridor coaches, though in Great Britain 65 ft. 6 in. has been the usual limit. To distribute their greater weight and to afford smoother riding, it was always thought necessary in the past to mount these vehicles on six-wheel instead of four-wheel bogies. But such has been the improvement in bogie design and in coach suspension generally that in practically every country in the world the four-wheel bogie is now regarded as adequate to carry the heaviest vehicles, the only exception being certain extremely weighty double-deck coaches in the United States. The earliest railway coaches were built almost entirely of wood,frames included,but by the end of the last century steel was coming into use for frame construction,though it was a good many years later before steel body construction came into anything like general use. Apart from greater strength and durability,steel commended itself as giving greater protection from telescoping and from fire in the event of a collision or derailment. With these developments and the provision of more and more amenities for passengers, coach weights steadily increased until in the United States some of the heaviest all-steel twelve-wheel cars were weighing as much as 80 or even 90 tons apiece. On the Continent of Europe 55 tons was and still is a common weight for a sleeping-car,and 45 tons for a corridor coach, but in Great Britain 46to 48 tons for restaurant or kitchen car, 42 to 44 tons for a sleeping-car, and 33 to 35 tons for a corridor coach are the present limits. Today, with lightweight steel and aluminum alloys of great strength at their command, engineers are realizing the waste of power involved in hauling trains of excessively heavy rolling stock,and are doing their utmost in their modern designs to bring these weights down. In Europe Switzerland has set a shining example in this respect. The latest lightweight second-class coaches,73 ft. long and seating 80 passengers apiece,weigh no
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more than 25 to 27 tons,as compared with the previous 34 to 36 tons of less capacious vehicles,and yet have perfect riding properties. In Great Britain the progress in weight reduction has not been so great and the modern 63 ft. 6 in. standard corridor coaches each turn the scale at 33 or 34 tons. The early coaches were provided with ‘dumb’ or solid buffers only,and were coupled by chains,so that starting and stopping could be a highly jerky business for the travelers. This was changed with the advent of spring buffers and of screw couplings. The latter, consisting of two links joined by a screw,make it possible exactly to adjust the distance between two coaches, the curved faces of the buffers must be brought just nicely into contact to give the greatest assistance to smooth riding. When screw couplings were first introduced,it was first thought necessary to supplement them, for safety’s sake, with a pair of the previous chain couplings, but the latter have long since been dispensed with. The pull on the drawbar is transmitted to the coach frame through the medium of springs, which are some protection, though not a complete one, against jerky starting. A good many years ago there was evolved in the Unite States the buckeye automatic coupling,and this is now standard over the whole of North America. It is now also the standard for British Railways. The coupler resembles a jointed steel hand, extended horizontally, which engages automatically with the couple of the next coach when the two are pushed together ;release is by the withdrawal of a pin. A train so coupled is therefore one continuous articulated unit,and this characteristic is of value,not only in promoting smooth riding,but also,in the event of a collision or derailment,in helping to prevent the telescoping of coaches which has caused so many casualties in the past. Some former railways took special measures to protect their coaches against the possibility of telescoping. The Great Central Railway,for example,fitted its coach ends with massive castings,in form like several rows of horizontal teeth,designed to engage if one coach-body were pushed off its frame, so to prevent it from telescoping through the and next coach-body in front. In these days,however,considerable attention is paid to the design of coach-bodies, to give adequate resistance against crushing. This is really a difficult problem,as it would be possible to build coaches of such strength that passengers might be killed by shock alone in the event of violent collision . The aim is that, possible, if such dangerous forces shall be absorbed before they do serious damage .In some modern coach designs in France and the Unite States,a tubular structure is incorporated which combines the coach-body with the frame,and this permits some lightening of the coach weight .

Railway Terms and New Words
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chassis truck bogie pivot vestibule advent buffer screw coupling automatic coupling coupler drawbar telescope amenity casting tubular n. n. v. n. n. a. n. n. n. n.

车身底架,底盘 卡车,底架 (铁路车辆)转向架 中心销,中心点 通过台,连廊,折棚 出现,到来 缓冲装置,缓冲器 螺旋钩 spring buffer 弹簧缓冲器

chain coupling

链子钩(均为旧式车钩)

自动连挂,自动车钩 车钩 拉杆,牵引干 套撞 愉快,舒适 铸件 管形的,圆筒形的

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Chapter 6 ATP Transmission and Moving Block

We have seen in the previous articles that the ATP signalling codes contained in the track circuits are transmitted to the train. They are detected by pick-up antennae (usually two) mounted on the leading end of the train under the driving cab. This data is passed to an on-board decoding and safety processor. The permitted speed is checked against the actual speed and, if the permitted speed is exceeded, a brake application is initiated. In the more modern systems, distance-to-go data will be transmitted to the train as well. The data is also sent to a display in the cab which allows the driver of a manually driven train to respond and drive the train within the permitted speed range. At the trackside, the signal aspects of the sections ahead are monitored and passed to the code generator for each block. The code generator sends the appropriate codes to the track circuit. The code is detected by the antennae on the train and passed to the on-board computer. As we have seen, the computer will check the actual speed of the train with the speed required by the code and will cause a brake application if the train speed is too high. Beacon Transmission

In the examples so far, the ATP data from the track to the train is transmitted by using coded track circuits passing through the running rails. It is known as the "continuous" transmission system because data is passing to the train all the time. However, it does have its limitations. There are transmission losses over longer blocks and this reduces the effective length of a track circuit to about 350 metres. The equipment is also expensive and vulnerable to bad weather, electronic interference, damage, vandalism and theft. To overcome some of these drawbacks, a solution using intermittent transmission of data has been introduced. It uses electronic beacons placed at intervals along the track.

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In the best known system, marketed by Adtranz, there are usually two beacons, a location beacon to tell the train where it is and a signalling beacon to give the status of the sections ahead. The beacons are sometimes referred to as "balises" after the French. Data processing and the other ATP functions are similar to the continuous transmission system. Operation With Beacons

The beacon system operates as shown in the simplified diagrams below. In the diagram (left), the beacon for red Signal A2 is located before Signal A1 to give the approaching train (2) room to stop. Train 2 will get its stopping command here so that it stops before it reaches the beacon for signal A3.

In the diagram on the left, the train has stopped in front of Signal A2 and will wait until Train 2 clears Block A2 and the signal changes to green. In reality, it will not move even then, since it requires the driver to reset the system to allow the train to be restarted. For this reason, this type of ATP is normally used on manually driven systems. Intermittent Updates

A disadvantage of the beacon system is that once a train has received a message indicating a reduced speed or stop, it will retain that message until it has passed another beacon or has stopped. This means that if the block ahead is cleared before Train 2 reaches its stopping point and the signal changes to green, the train will still have the stop message and will stop, even though it doesn't have to. Why, might you ask, can't the driver cancel the stop message like he does when the train has stopped and the signal changes to green? If he could cancel the stop message while the train was moving, the system would be no better than the AWS with its cancel button. ATP is "vital" or "fail-safe" and must not allow human intervention to reduce its effectiveness. To avoid the situation of an unnecessary stop, an intermediate beacon is
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provided.

This updates the train as it approaches the stopping point and will revoke the

stop command if the signal has cleared. More than one intermediate beacon can be provided if necessary. Moving Block - The Theory As signalling technology has developed, there have been many refinements to the block system but, in recent years, the emphasis has been on attempts to get rid of fixed blocks altogether. Getting rid of fixed blocks has the advantage that you can vary the distances between trains according to their actual speed and according their speeds in relation to each other. It’s rather like applying the freeway rules for speed separation - you don’t need to be a full speed braking distance from the car in front because he won’t stop dead. If you are moving at the same speed as he is, you could, in theory, travel immediately behind him and, when he brakes, you do. If you allow a few metres for reaction time to his brake lights and variations in braking performance, it works well. Although it only needs a few spectacular collisions on the freeways to disprove the theory for road traffic, in the more regulated world of the railway, although it could not be applied without a full safe braking distance between trains, it has possibilities.

In the diagram (left), as long as each train is travelling at the same speed as the one in front and they all have the same braking capabilities, they can, in theory, run as close together as a few metres. Just allow some room for reaction time and small errors and trains could run as close together as 50 metres at 50 km/h. Well, that’s OK in theory but, in practice, it’s a different matter and, as yet, no one has taken moving block design this far and they are unlikely to do so in the near future. The recent ICE high speed accident in Germany where a train derailed, struck a bridge and stopped very quickly, effectively negates the safety value of the theoretical moving block system described above. This means that it is essential to maintain a safe braking distance between trains at all times. What is worth doing, is making the the block locations and lengths consistent with train location and speed, i.e. making them movable rather than fixed. This flexibility requires radio transmission, sometimes called Communications Based Train Control (CTBC) or Transmission Based Signalling (TBS) rather than track circuit transmission, to detect the location, speed and direction of trains and to tell trains their permitted operating speed. Moving Block and Radio Transmission

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On a moving block equipped railway, the line is usually divided into areas or regions, each area under the control of a computer and each with its own radio transmission system. Each train transmits its identity, location, direction and speed to the area computer which makes the necessary calculations for safe train separation and transmits this to the following train as shown here (left). The radio link between each train and the area computer is continuous so the computer knows the location of all the trains in its area all the time. It transmits to each train the location of the train in front and gives it a braking curve to enable it to stop before it reaches that train. In effect, it is a dynamic distance-to-go system. This is Communications Based Train Control (CTBC). One fixed block feature has been retained - the requirement for a full speed braking distance between trains. This ensures that, if the radio link is lost, the latest data retained on board the following train will cause it to stop before it reaches the preceding train. The freeway style vision of two trains moving at 50 km/h with 50 metres between them is a step too far into virtual reality for most operators. Moving Block - Location Updates

As we have seen, trains in a moving block system report their position continuously to the area computer by means of the train to wayside radio. Each train also confirms its own position on the ground from beacons, located at intervals along the track, which recalibrate the train’s position compared with the on-board, computerised line map. Transferring a train from one area to another is also carried out by using the radio links and, additionally by a link between the two adjacent area computers. The areas overlap each other so, when a train first reaches the boundary of a new area, the computer of the first area contacts the computer of the second area and alerts it to listen for the new train’s signal. It also tells the train to change its radio codes to match the new area. When the new area picks up the ID of the train it acknowledges the handover from the first area and the transfer is complete. Another version of the moving block system has the location computers on the
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trains. Each train knows where it is in relation to all the other trains and sets its safe speeds using this data. It has the advantage that there is less wayside equipment required than with the off-train system but the amount of transmissions is much greater. An Early Moving Block System One system which claims the distinction of being the first moving block system is that marketed under the name Seltrac by Alcatel. It is used in Canada and on the Docklands Light Railway in London. It has the ingredients of moving transmission of data, but the transmission medium is the track-mounted induction loops which are laid between the rails and which cross every 25 metres to allow trains to verify their position. Data is passed between the vehicle on-board computer (VOBC) and the vehicle control centre (VCC) through the loops. The VCC controls the speed of Train 2 by checking the position of Train 1 and calculating its safe braking curve. More detail on this system is here

The Seltrac system requires no driver, as it is fully automatic. In case of a system failure where a train has to be manually driven, it has axle counters? to verify the position of a train not under the control of the loops. Perhaps its biggest drawback is the need for continuous cables to be laid within the tracks, expensive to install and open to damage during track maintenance. The principle difference between this system and the more modern ones being marketed today is that Seltrac uses electro-magnetic transmission of data requiring track cables, whereas radio based systems only require aerials. Seltrac is upgrading their design to use radio based transmission. Moving Block - Why Do We Need It? Railway signalling has traditionally required a large amount of expensive hardware to be distributed all along a route which is exposed to variable climatic conditions, wear, vandalism, theft and heavy usage. Because of the widely spaced distribution, maintenance is expensive and often restricted to times when trains are not running. Failures are difficult to locate and difficult to reach. tunnels and elevated sections. On metros, access is further restricted where there are For these reasons, railway operators have been trying to

reduce the wayside signalling equipment and so reduce maintenance costs. Reduced wayside equipment can also lead to reduced installation costs. Moving block requires less wayside equipment than fixed block systems. There is another goal much sought after by operators - greater capacity. A norm for most metro lines is 30 trains per hour (tph) or a two-minute headway. It is debatable
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whether much improvement on this is possible for a high capacity system, since the major losses of line capacity occur because of station stops and terminal operations. Heavily used metro lines, like those in Hong Kong, trying for a greater capacity than 30 trains per hour, will struggle to keep dwell times below 40-50 seconds at peak times. This will push the headway to two minutes or longer, regardless of the signalling system used. Similar problems exist at terminals where crossover clearance times are critical. Moving block signalling cannot provide much improvement. Shorter headways can, however, be achieved on systems where trains are shorter, speeds lower and the passenger levels smaller. In some places a 95 second headway can be achieved on systems like Docklands and certain sections of the Paris Metro. Also, for underground lines, modern ventilation and smoke control systems will require train separation of 2-300 metres to allow air circulation at critical times. If moving block signalling allows 50 metre separation, some very expensive additional ventilation arrangements might be necessary. This may reduce the benefits of moving block. The real prize which could be won by an operator using moving block is reduced wayside equipment and reduced maintenance costs. included, an all-round improvement can be achieved. One other factor to be noted is that many operators specifying moving block technology also ask for fixed block track circuits to serve as a back up and for broken rail detection. Track circuits are also still required for junctions. One might ask, if such equipment is to be installed anyway, why add the expense of radio-based transmission? Better reliability and quicker fault If radio based transmission is location is also possible with moving block technology.

Reading Material
Automatic Train Operation
So far, we have only seen how ATP systems work on metros. ATP is the safety system which ensures that trains remain a safe distance a part and have sufficient warning to allow them to stop without colliding with another train. ATO (Automatic Train Operation) is the non-safety part of train operation related to station stops and starts. The basic requirement of ATO is to tell the train approaching a station where to stop so that the complete train is in the platform. This is assuming that the ATP has confirmed that the line is clear. The sequence operates as shown below.

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The train approaches the station under clear signals so it can do a normal run in. When it reaches the first beacon - originally a looped cable, now usually a fixed transponder - a station brake command is received by the train. The on board computer calculates the braking curve to enable it to stop at the correct point and, as the train runs in towards the platform, the curve is updated a number of times (it varies from system to system) to ensure accuracy. London’s Victoria Line, now 35 years old, has up to 13 "patches" checking the train speed as it brakes into a station. This high number of checks is needed because the on-board braking control gives only three fixed rates of deceleration. Even then, stopping accuracy is ± 2 metres. here. A detailed description of the Victoria Line's ATO system is Modern systems require less wayside checking because of the dynamic and more

accurate on-board braking curve calculations. Now, modern installations can achieve ± 0.15 metres stopping accuracy - 14 times better. Metro Station Stops ATO works well when the line is clear and station run-ins and run-outs are unimpeded by the train ahead. However, ATO has to be capable of adapting to congested conditions, so it has to be combined with ATP at stations when trains are closely following each other. Metro operation at stations has always been a particular challenge and, long before ATO appeared in the late 1960s, systems were developed to minimise the impact when a train delayed too long at a station.

To provide a frequent train service on a metro, dwell times at stations must be kept to a minimum. In spite of the best endeavours of staff, trains sometimes overstay their time at stations, so signalling was been developed to reduce the impact on following trains. To see how this works, we begin with an example (left) of a conventionally signalled station with a starting Signal A1 (green) and a home Signal A2 (red) protecting a train (Train 1) standing in the station. We can assume mechanical ATP (trainstops) is provided so the overlap of Signal A2 is a full speed braking distance in advance of the platform. As Train 2 approaches, it slows when the driver sees the home Signal A2 at danger. Even if Train 1 then starts and begins to leave the station, Signal A2 will remain at danger until Train 1 has cleared the overlap of Signal A1. Train 2 will have to stop at A2
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but will then restart almost immediately when Signal A2 clears. second train to keep moving. It is called multi-home signalling. Multi Home Signalling - Approach

This causes a delay to

Train 2 and it requires more energy to restart the train. A way was found to allow the

Where multi-home signalling is installed at a station (left), it involves the provision of more but shorter blocks, each with its own signal. The original home signal in our example has become Signal A2A and, while Train 1 is in the platform, it will remain at danger. However, Block A2 is broken up into three smaller sub-blocks, A2A, A2B and A2C, each with its own signal. They will also be at danger while Train 1 is in the platform. Train 2 is approaching and beginning to brake so as to stop at Signal A2A. When Train 1 begins to leave the station, it will clear sub-block A2A first and signal A2A will then show green. Train 2 will have reduced speed somewhat but can now begin its run in towards the platform. Multi Home Signalling - Run In

At this next stage in the sequence, we can see (left) that Train 1 has now cleared two sub-blocks, A2A and A2B, so two of the multi-home signals are now clear. Note that the starting signal is now red as the train has entered the next block A1. Train 2 is running towards the station at a reduced speed but it has not had to stop. When Train 1 clears the overlap of signal A1, the whole of block A2 is clear and signal A2C clears to allow Train 2 an unobstructed run into the platform. ATO/ATP Multi Home Signalling

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Fixed block metro systems use multi-home signalling with ATO and ATP. A series of sub-blocks are provided in the platform area. These impose reduced speed braking curves on the incoming train and allow it to run towards the platform as the preceding train departs, whilst keeping a safe braking distance between them. Each curve represents a sub-block. Enforcement is carried out by the ATP system monitoring the train speed. The station stop beacons still give the train the data for the braking curve for the station stop but the train will recalculate the curve to compensate for the lower speed imposed by the ATP system. ATO Docking and Starting

In addition to providing an automatic station stop, ATO will allow "docking" for door operation and restarting from a station. If a "driver", more often called a "train operator" nowadays, is provided, he may be given the job of opening and closing the train doors at a station and restarting the train when all doors are proved closed. Some systems are designed to prevent doors being opened until the train is "docked" in the right place. Some systems even take door operation away from the operator and give it to the ATO system so additional equipment is provided as shown left. When the train has stopped, it verifies that its brakes are applied and checks that it has stopped within the door enabling loops. These loops verify the position of the train relative to the platform and which side the doors should open. Once all this is complete, the ATO will open the doors. After a set time, predetermined or varied by the control centre as required, the ATO will close the doors and automatically restart the train if the door closed proving circuit is complete. Some systems have platform screen doors as well. ATO will also provide a signal for these to open once it has completed the on-board checking procedure. Although described here as an ATO function, door enabling at stations is often incorporated as part of the ATP equipment because it is regarded as a "vital" system and requires the same safety validation processes as ATP.
Once door operation is completed, ATO will then accelerate the train to its cruising speed, allow it to coast to the next station brake command beacon and then brake into the next station, assuming no intervention by the ATP system.

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Chapter 7

Control of Railway Operation

Traffic Control with Local Operators
Non Signal-controlled Lines In a non signal-controlled operation, the traffic is controlled by a dispatcher who issues verbal or written instructions. Before the introduction of the radio, all communication was made by telephone. The telephone operators at local train order stations received instructions from the dispatcher and relayed them to the train crews. Interlocking towers also worked as train order stations. In addition to staffed train order stations, some railways also used un-staffed telephone stations where the train crews had to call the dispatcher via a local telephone for authority to proceed. On European branch-lines, a telephone-controlled operation without a dispatcher was very common. There, the traffic was regulated by exchanging telephone train messages between local operators in a manner similar to the telephone block system. But the authority to proceed was issued verbally to the train crews. Signals were only used at junctions and at the entrance of frequently used passing tracks. After the European railways had seen the advantage of dispatcher control on lines which were operated by US Military Railway Service during the war, most of these lines were changed to a dispatcher-controlled operation. Since the introduction of the radio, most communication is made directly between the dispatcher and the train crews. Except from interlocking towers, file staffed train order stations disappeared. The great advantage of the use of radio is that a train may be reached at any time. But on the other side, this leads to an increasing amount of communication. In telephone operation, the dispatcher can prepare a solution, then call a local operator and transmit orders for a number of trains. In a radio-controlled operation, the dispatcher has to call every single train. Due to the increasing number of calls, the dispatcher will have less time for traffic regulation. l Signal-controlled Lines On conventional railway lines with a signal-controlled operation, points and signals are operated by interlocking machines located in interlocking towers. (signal boxes) and controlled by local operators (Figure 1). l

Figure 1

Traffic Control with Local Operators on a Signal-controlled Line
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The operators of neighbouring interlockings communicate to each other by means of telecommunication, mostly by simple telephone connections. All communications between the interlockings and all train movements are registered by the operators in train records. On North American railways all lines are controlled by a dispatcher who works in a centralised office. On European railways this applies only on lines with a heavier traffic, while lines with low traffic are operated without a dispatcher. The reason is, that because of the different operating procedures of North American and European Railways the role of the dispatcher is also very different. Compared with European railways, in North American practice the dispatcher has a much higher authority. On North American lines, the dispatcher is the person who issues movement authorities to trains. The local operators are in some way only the "lengthened arms" of the dispatcher to set up routes, clear signals and transmit orders in compliance with the dispatcher's instructions. For a detailed description of North American train dispatching see the book "Elements of Train Dispatching" by Thomas White. On European railways, the movement authorities are issued by the local operators. Because the local operator is the "authority person", the dispatcher is only responsible for watching the traffic and for solving scheduling conflicts to avoid delays and congestion. Thus, the dispatcher supports the local operators in an efficient operation. Regarding the local operators there is also a difference between British and German operating procedures. On British railways, the local operator who issues movement authorities is called a signalman. A signalman is in full charge of issuing movement authorities within the station limits of the signal box. Concerning the authorisation of train movements, all signal boxes have equal rights. On German railways, there are two classes of local operators and also two classes of interlocking towers. Only a train director is in charge to authorise train movements. The train director does all communication that is needed for traffic regulation (train messages and communication with the dispatcher). In extended home signal limits a train director may have authority over a district with a number of interlocking towers. The train director's tower (the command tower) is electrically connected with the dependent towers by a command interlocking system (see Section 4.1.9). The dependent towers are staffed only with levermen who must not clear a signal or issue any written authority to a train without a command from the train director. But the levernan may authorise shunting movements on his own responsibility. l Dispatcher Sheets On lines supervised by a dispatcher, the local operators report all arrival and departure times to the dispatcher who registers this information in a graphic or tabular dispatcher sheet. As a matter of tradition, North American railways use tabular sheets while almost all railways outside of North America prefer graphic ones (Figures 2and 3). Like traffic diagrams, graphic dispatcher sheets may be designed with a horizontal or a vertical station axis. The dispatcher sheet gives an overview of the operational state of the line and enables the dispatcher to early recognize trouble-making situations. So, he can make decisions concerning traffic regulation (e.g. changing the sequence of trains)
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and give instructions to the local operators.

Figure 2

Cut out from a North American Dispatcher Sheet

Figure 3

Cut out from a German Dispatcher Sheet

Centralized Traffic Control
In Centralized Traffic Control (CTC) all points and signals inside the controlled area are directly controlled by the dispatcher (Figure 4). All train movements are governed by signal indication. The local interlockings are remote-controlled without local staff. In CTC territory all main tracks must be equipped with track clear detection. CTC technology has a long tradition on railways which operate long lines in territories with a very low population density and long distances between stations. Typical
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examples are lines in North America and in Russia. With the introduction of CTC, some of the essential differences between railways which follow North American, British or German operating procedures partly disappeared. In a CTC territory, the work of a North American dispatcher would not differ from the work of a British signalman or a German train director in such a significant way as it does on lines with traditional operating procedures.

Figure 4

Centralized Traffic Control

l Automation Technologies Even on lines with modern interlocking technologies (microcomputer interlockings 微 机联锁) there is still a lot of manual action of operators and dispatchers needed to operate a railway system. To reduce this manual action automation technologies have been developed. Nowadays, these technologies are used both on lines with local operators and on CTC lines. Train Describers A train describer is a system that identifies trains which occupy a block section on the display at the panel of the operator or dispatcher. Modern train describing systems also provide an automatic registration of all train movements for later evaluation of delays and irregularities. Thus, for regular train movements, hand-written train records are no more required. Train describers also replace the telephone communication otherwise used between the operators of neighboured interlockings to inform each other about train movements. But in difference to signalling devices like interlocking and block systems, a train describer is not a fail safe system. The information presented by a train describer must only be used for traffic regulation but not for safety purposes. For train movements under special conditions, in which the safety cannot completely provided by the signalling system and a safe communication between operators is required, this communication must be done by telephone and manually recorded. In such cases, hand-written train records are still required. There are three different principles to realize a train describer: ˙Trains are identified when entering the controlled area (e.g. by manual input). Inside the controlled area the train description is forwarded from section to section using information about track occupations which is provided by the signalling system.
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l

˙Trains are equipped with tags containing the train description. The tags can be read by trackside devices. ˙Train location is done aboard the trains (e.g. by GPS or by reading trackside balises). Train location and train description are transmitted to the control centre (interlocking tower or CTC office) by radio. It is very advantageous to have a train describer system which works independently from the signalling systems. So, in case of a malfunctioning of the components of the signalling system the train describer could still work properly. In cases of trouble caused by faults of the signaling system it is of great importance to the operator to have a complete overview of all train locations and train descriptions. In control centers responsible for larger areas the information provided by train describers is often used to display the traffic in form of a traffic diagram quite similar to the traffic diagrams used in scheduling. So, the dispatcher can easily compare the real traffic of a line with the scheduled traffic. These dispatcher displays replace the manually drawn graphic dispatcher sheets. To achieve a better conflict recognition and solving, most systems project the scheduled time-distance curves into the future. But apart from some very advanced dispatcher systems the preview is mostly not very realistic because blocking times and minimum headways are not considered. They are, however, an important tool for an experienced dispatcher. Automatic Route Setting Automatic route setting (ARS), also known as automatic train routing (ATP), provides the automatic setting of the proper route when a train approaches a signal. An ARS system must contain three functions: ˙automatic route selection when approaching a facing point signal, ˙output of the route setting command at a proper time, ˙solving conflicts of conflicting routes. For automatic route selection two principles are common: ˙route selection by a programmed route sequence, ˙route selection by the train description. When routes are selected by a programmed route sequence,a route program exists for every facing point signal that contains all routes in a programmed sequence. When a train is approaching the program will switch to the next position and hand out the route which is to be set up next (Figure 5). Such a control logic is quite simple but it has the disadvantage of bad routing when trains do not run in accordance to the scheduled train sequence. Such a system is only useful on lines where the trains run on a fixed timetable on which train sequences are changed very seldom. This is characteristic of subways and electric city railways. One of the first ARS devices following this principle had been installed for the purpose of automatic junction working in the London Underground in the 1950s. If the train sequence needs to be changed,then the operator will manually change the contents of the route program. In route selection by train description a train that is approaching a signal is not only registered but also identified by its train description. The ARS system has access to a
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file which contains the routes of all scheduled trains.

Figure 5

Route Selection by a Programmed Route Sequence

Figure 6 Route Selection by Train Description When a train is approaching a signal a route selection processor will read the route which belongs to the train description from this file (Figure 6). Such a system works independently from the real train sequence. On lines with mixed traffic this principle is more suitable than route selection by scheduled event sequence. However, route selection by train description requires train describers to provide the train description information. The optimum time to clear a signal is when the train is in sighting distance in approach to the signal that provides the approach indication to the entrance signal of the route (a separate distant signal or the block signal in rear). The command to set up a route should be issued as early as needed to meet this condition considering the time required for operating the points. But the route setting command should not be issued too early in order to prevent an unnecessary increase in the blocking time because this in turn would cause a lower capacity. The optimal location of the approach point for the automatic setting up of a route can be derived from figure 7.
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Figure 7 Optimal Approach Point for Automatic Route Setting There are two strategies to handle train path conflicts in an ARS system: ˙timetable-based ARS ˙destination-based ARS In a timetable-based ARS system all routes are set up in compliance with the scheduled train sequence. When a train path conflict occurs, a train would always wait for a delayed train that is scheduled ahead of its own train path. A timetable-based ARS system always works with route selection by train description and requires a database that contains not only the routes but also the timetable data of all trains. Train path conflicts can only be solved by altering the timetable. That requires a connection of the ARS system to a computer-based dispatching system. When a decision to change the train sequence has been made, the dispatching system would automatically create new timetable data for the ARS system. A destination-based ARS system would automatically set up routes regardless of the scheduled train sequence. The route selection can be done by a programmed route sequence or by train description. For route selection by train description can be either used a database that contains the routes of all trains or a special destination code (e.g. a destination number) as a part of the train description. When in a destination-based ARS system two trains are approaching conflicting routes and the time interval for passing the intersection between the trains is less than the minimum headway a decision must be made as to which train may pass first. For this purpose the trains have to be registered by the ARS system before reaching the approach point for automatic route setting. This could be done by reserving a certain length of the track for every train in front of the sections the train has just blocked. If at an intersection the reserved length of different trains overlap,then the train with higher priority is to pass first (Figure 8).

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Figure 8 Priority Decision at an Intersection Another form of conflict which call be solved by an ARS system is deadlock. A deadlock (on North American railways also colloquially called a "Jackpot") is a situation in which a number of trains cannot continue their path at all because every train is blocked by another one (Figure 9). The probability of such situations is particularly high on single track lines containing some passing tracks and a high density of traffic. But deadlocks may also occur in complex interlocking arrangements.

Figure 9 Simple Deadlock Examples Avoiding deadlocks is a pure problem of event sequence. Once a chain of interdependencies has closed to a circle, there will be no way to escape the approaching deadlock. Before setting a route to authorise a train movement by clearing a signal, the ARS system has to check that the proceeding of the train will not lead to a deadlock. Avoiding deadlocks is a very essential function of an ARS system to make real automatic train routing possible. But today, in many destination-based ARS installations avoiding deadlocks is still not implemented in a very sufficient way. So, on lines with a high probability of deadlocks there is still a high degree of dispatching work to be done by the operator. In a timetable-based ARS system deadlocks must be avoided by the dispatching system that creates the timetable database. Because this type of an ARS system would control train movements in compliance with the timetable that was created by the dispatching system, there is no need for a deadlock avoiding logic in the ARS system.
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Computer-based Dispatching A computer-based dispatching system supports the dispatcher in solving schedule conflicts in a current operation. The heart of computer-based dispatching is a rescheduling system which offers the following functions: ˙preview of train movements (usually for the next I or 2 hours), ˙detection of incoming schedule conflicts, ˙proposals of how to solve schedule conflicts. The preview of train movements is done by projecting the future train paths. To obtain a realistic view of future movements the projection has to be done under consideration of the blocking times of other train paths which will join the same route. In case of overlapping blocking times the train path of lower priority has to be postponed. So, the preview is done as an iteration between calculation of the train paths and calculation of the blocking times (Figure 10).

Figure 10 Iteration between Calculation of Train Paths and Blocking Times Schedule conflicts are detected by overlapping blocking times and are solved by postponing the train paths. The development of systems to automatically solve schedule conflicts is still in a very early stage. An idea regarding such a system is to create a number of solutions by varying the event sequence. Serving as an example, Figure 11 shows a traffic diagram with a schedule conflict caused by an input delay of train 1. Figure 12 shows the corresponding event sequence graph. Every node corresponds to an event in the traffic diagram. The single arrows mark event sequences which cannot be changed in further operations. The double arrows mark event sequences which are still changeable. From this event sequence graph can be created a number of event sequence graphs which still contain only single arrows. Every one of these event sequence graphs represents a single solution of the schedule conflict. By rating these solutions (e.g. by the sum of delays) there can be found the best solution to use for rescheduling.

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Figure 11 Traffic Diagram Example with a Schedule Conflict

Figure 12 Event Sequence Graph of the Example of Figure 11 The development of computer-based dispatching systems with an automatic conflict detection and solving is still in an early stage. And, there are still discussions between experts about the reasonable level of automation in a railway system. Although sometimes suggested, a complete automation of traffic control would not make any sense. The most very valuable advantage of automation technology is to allow the dispatcher to devote attention to pending and current problems while most of the railway runs automatically. But the automation technology would not be able to act on emergency information as failures of technical equipment (rolling stock, signal, track), derailments, bomb scares, bad weather, etc. That means, that with an increasing level of automation, handling of emergency situations and other irregularities will become an increasing share of the dispatcher's workload. Because the sum of emergency operation will not be reduced by automation, the staff of a control center must never be reduced by the same degree as the regular operation is automated. There must always be a
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sufficient reserve to handle emergency operations. The management must keep this in mind when determining the number of employees in a highly centralized and automated operation. Otherwise, the operation of a railway network may collapse in emergency situations. Control Centers In a traditional CTC operation the dispatcher both operates the CTC machine and does the traffic regulation. The territory that one dispatcher can control is mainly limited by the workload for authorizing all train movements. Performance can deteriorate from lack of planning time before the physical limitation of authorizing trains occurs. On railways with a high density of traffic a dispatcher could only control quite a small district. If the dispatcher has access to a train describing system that provides traffic information from outside his own district he will get an overview to the operation of the line. But he can only make decisions inside his small control area. And, the visual information from the train describers may not alone provide sufficient information for planning. There may be required additional communication that increases the workload. Thus, the traffic regulation is not very efficient. That is why in control centres with a lot of dispatcher workstations many railways decided to introduce another structure of operation control. In this structure the traffic regulation is separated from the CTC operation. Traffic regulators (on North American railways called chief dispatchers) supervise the operation of a whole line or a large terminal area. These employees watch the operation and make decisions to solve scheduling and train path conflicts, running extra trains and so on. But they do not directly authorise train movements. All movements are authorised by CTC operators who work below the traffic regulators (Figure 13). The CTC operators are responsible for a safe movement authorisation, both in regular and in emergency operation. Only the CTC operators may issue written orders to the train staff. Shunting on main tracks is also completely in charge of the CTC operators. Because the CTC operators are relieved from traffic regulation they can completely concentrate on a safe operation. The number of CTC operators who work inside the control area of one traffic regulator may vary over the day in dependence from the traffic density and emergency situations. In addition to the traffic regulators and CTC operators there are usually special workstations for emergency and maintenance management and for scheduling. The scheduling workstations are not used for the regular scheduling process but for scheduling of extra trains and for rescheduling in case of emergencies or failure of equipment.

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Figure 13 Typical Structure of a Control Centre In modem control centers the workstations of the traffic regulators are both equipped with screens which show the location of all trains in the track layout in a similar way like a CTC display and with screens which display a traffic diagram with the time-distance-graphs projected into the future (as shown in Figure 11). To solve a scheduling or train path conflict the traffic regulator can use the mouse to move the train paths to positions without overlapping blocking times. In most advanced systems the control system of the traffic regulator generates automatically the control data for the automatic route setting (ARS) system. This requires a timetable-based ARS system. Such a system leads to a very high degree of automation with a low number of operators to handle the regular traffic. But the extremely increasing workload in emergency operation would require reserve operators. The number of reserve operators depends on the reliability of the automatic operation.

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Chapter 8 Train Station Passenger Flow Study
ABSTRACT
With the increasing demand for public transportation due to congested highways, trains have become one of the most viable alternatives, especially for daily commuting. While transit agencies are excited with the increasing ridership, hey are also challenged with a higher volume of passenger flow and longer queuing lines at the existing stations. To improve the current situation and plan for the future, transit agencies are using simulation tools to help evaluate station design, queue management, fare equipment design and fare policy impacts.

1

INTRODUCTION
When traveling by train, the station is the first and last encounter a passenger

experiences. Every passenger must access the station before boarding the train and must exit the station upon arrival at the final destination. While at the station, a passenger often travels on escalators or stairs, purchases a ticket, and goes through the fare collection gates before and after a train ride. For transit agencies, it is important to include all these encounters into the evaluation of total passenger travel times when developing service improvements at the stations With increasing highway traffic in many metropolitan cities, more commuters are taking the trains to work. Beside the need to evaluate station capacity to accommodate the weekday peak period ridership, agencies are also evaluating new fare collection equipment to replace aging units. With a complex environment, agencies are using simulation to optimize operations and service quality.

2

APPLICATION
In light of each transit agency having its own operating policies and each train station

having a unique design and layout, agencies share similar challenges in handling passenger flow. Figure 1 showed a general passenger flow chart with listing of key station activities and their relationships. The time required to complete each activity is a function of fare structures, fare collection policies, station layout, equipment design, operating policies and system capacity. Agency staffs often are available only at major terminal stations and their job functions are assisting passengers at information booth, selling train tickets, and guarding the areas.In
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the past, transit agencies have used simulation to help addressed the following train station passenger flow related issues: l Fare Equipment Type Mix Optimization. There are various types of fare equipment; such as ticket vending machines, ticket collecting turnstiles, exit only turnstiles and cash dispensing turnstiles. Agencies need to determine an optimal combination of these equipment. An example would be determining the numbers of bidirectional versus one-way fare gates to mitigate the impediments between passengers entering and exiting the various machines at the same time. l Fare Policy Change. When there is a proposed fare increase or introduction of a new ticket type, it often increases the time spent purchasing a ticket with cash from a ticket vending machines. Since a passenger may need to put more bill(s) or coin(s) into a machine. Therefore, agencies may need to install additional machines or relocate currently underutilized machines to areas with higher projected traffic volume. l Fare Equipment Performance. Agencies use simulation for assessment of fare equipment performance criteria. This is often done during procurement of new fare equipment as there is need to determine equipment transaction speed and user interface screen numbers. These factors drive the amount of time a passenger would spend at the machine. l Train Scheduling. Many train stations offer transfers between rail lines. The transfer often required passenger to go through fare gates and escalators/stairs. To determine the passenger arrival rates and walking patterns at stairways, transfer gates and exiting turnstiles, it is important to evaluate frequency of train arrival and the numbers of passengers getting off the train. l Equipment Maintenance Schedule. Besides planning for normal operations, agencies also developed station operations back up plans for scheduled and unscheduled equipment downtime due to failure or maintenance. The equipment could be the fare collection equipment or the ingress and egress media . stairs, escalators and elevators. l Station Layout. To minimize passenger travel time and frustration, ingress and egress media, fare equipment, main station entry/exit points, rain boarding/exiting points on platform should be strategically layout. l Ingress and Egress Safety Compliance. Agencies also use simulation models to evaluate the quantity and capacity of stairs, escalators and elevators in the station. Train stations must be designed with adequate ingress and egress media for efficient passenger evacuation during emergencies.
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Figure 1: Train Station Passenger Flow Chart

3 MODELING EFFORT
This section discusses the approach and effort used for developing a typical train station simulation model. 3.1 Input Requirements In most cases, simulation model input data includes both the average behavior (such as ridership, number of trains per hour, time to purchase a ticket using a credit card and escalator speed) and the distribution of the population behaviors (such as passenger arrival rate at the fare gate, types of ticket payment method by cash, credit or debit, varies walking speed, and choice of ingress/egress media.)Figure 2 shows a sample of input data used for the passenger flow study at the proposed Newark Northeast Corridor (NEC) Monorail Station. Input data could be historical data provided by the agencies, data from field observations, or design specification provided by the manufacturers. Different statistical distribution functions are often used for simulating various passenger arrival patterns at a station. In general, a passenger will get to a station by one of the following transportation modes: l Foot - walking l Taxi l Car l Subway/Train transfer
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l Bus transfer

Figure 2: Sample of Input Data Arrival rates of Train and bus transfers are driven by their scheduled arrival time and each arrival will bring a large volume of passengers. When simulating these passenger arrival rates, use either the scheduled arrival time or the Poisson distribution which will depend on the type of data available. Use the scheduled arrival time if the train/bus often
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has on-time arrival. Arrival rates for traveling by foot, taxi or car are more random and continuous; also, each arrival will ring a smaller amount of passengers. The exponential distribution is often used for simulating continuous arrival patterns. If a model is designed for evaluating the worst-case scenario, ridership shall be properly adjusted to reflect the busiest travel period. Such as multiplying the average peak period ridership by the following factors: l Ridership growth rate l Month of the year adjustment l Day of the week adjustment l Other adjustments special events. Beside numerical data, the station layout is another key input requirements. A layout shall include, at minimum, the ingress/egress media, fare collection equipment and primary station entry points that are included in the statistical analysis. If using a animated simulation model, the station layout screen could also include real time display of some of the key statistical results while the model is running. The graphical layout is especially useful for evaluating visual information on bi-directional fare equipment traffic and bottleneck areas. A sample layout of the Newark NEC Monorail Station is shown on Figure 3.

Figure 3: Snap Shot of the Newark NEC Station Simulation Model 3.2 Evaluation Criteria
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The primary evaluation criteria for determining an optimal solution are passenger processing time at various check points (such as ticket vending machines, ticket acceptance gates and exit turnstiles) and queue time and queue length at the bottleneck areas (such as fare machines and ingress/egress media.) Figure 4 showed one of the key simulation results -- number of passenger waiting in queue -- that is often used for evaluating the passenger flow rate. Other criteria could include: l The number of people missing their first available train due to delays in the queue line. l Equipment utilization rate. l Elapsed time between the first and the last passenger passed through a transfer point.

Figure 4: Sample of Simulation Result 3.3 Model Validation Simulation models are often validated by objective techniques. When evaluating an existing system, a base case model that simulates the current environment often is used for validating the model assumptions and logic. Once the model is calibrated, input requirements are changed for evaluating the “what-if” scenarios. Since most of the train stations have security cameras installed throughout the station, video observations are useful for comparison with simulation results. Also, results from field observations and interviews with experienced transit agencies are often included in the model validation process. 4 CONCLUSION
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Simulation is a powerful tool for train station passenger flow improvement, planning and design analysis. It provides numerical results and graphical animations of activities that take place from the time a passenger enters until departing the station. Transit agencies are integrating lessons learned from simulation into all aspects of passenger flow design/operations. From daily station operations management, scheduled maintenance planning to long term capital planning, simulation has proven to be a tool not only to address today’s problem, but it also capable of enabling users to adapt to tomorrow’s challenges..

Railway Terms and New Words
viable ridership function animation address effort specification scenario adjustment in light of adj. n. n. n vt. n n. n. n. adv 可行的 公共交通工具乘客(人数) [数]函数 活泼, 有生气 向...致辞, 演说, 写姓名地址, 从事, 忙于 成果 详述, 规格, 说明书, 规范 想定 调正, 整理; 修正, 位移,【数】平差 按照, 根据

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Chapter 9 Metrocard Fare Incentives
MetroCards – plastic magnetically coded swipe cards – were first introduced on a pilot basis in the early 1990s. Initial public reception of the cards was tepid. At that time, MetroCards could be used only at select subway stations where new turnstiles had been installed and on a limited number of buses. They offered no discounts. Even after all subway station turnstiles were upgraded and new fare boxes were installed in all buses, only 18% of trips were taken using MetroCards (spring of 1997). Transit customers embraced MetroCard, however, once fare incentives were introduced beginning in July 1997, as follows: l Free transfers between bus and subway and a liberalized transfer policy with only a few limits on transfers between buses, introduced in July 1997. Riders could transfer between bus and subway, or between almost any bus lines, within two hours of first boarding the bus or entering the subway. l Bonus MetroCards on purchases of $15 or more, introduced in January 1998. Riders buying a $15 MetroCard receive $16.50 on their card – 11 rides instead of 10. On purchases of over $15, 10% is added to the card, e.g., $2 on a $20 purchase. The bonus applies to purchases of new MetroCards as well as adding value to an existing card. l 7-day and 30-day unlimited ride passes, priced at $17 and $63 respectively, introduced in July 1998. In addition, the 30-day Express Bus Plus MetroCard was introduced, costing $120. The 7-day and 30-day periods begin after first use of the card and continue until midnight of the seventh or thirtieth day. The passes offer unlimited rides on New York City Transit’s subways and buses as well as private local buses operated primarily in Queens and the Bronx. The passes can only be used by one person at a time but can be shared at different times of the day. Each of these was valid for unlimited rides over the designated period from the day of first use. l One-day “fun passes,” priced at $4, introduced in January 1999. The one-day pass can be used for unlimited rides until 3 a.m. the day after it is activated. Originally available only at stores outside the subway system that sell MetroCards, the one-day pass can now also be bought at MetroCard vending machines in subway stations. Additional features have been offered to targeted customer segments since introduction of the one-day pass. l Riders employed by companies enrolled in the TransitChek program can subscribe to a “premium MetroCard” service and receive a pass they can use for a year. They pay $63 a month through monthly pre-tax payroll deductions; as a result they save 25% or more of the cost of the pass. l Reduced-fare riders (seniors and disabled) can obtain a MetroCard with photo identification showing they are entitled to the reduced fare. Payments can automatically be deducted from a credit/debit card or bank account. The card can
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be replaced if it is lost or stolen. Customers can report a lost or stolen card by phone and the card is deactivated to protect the user from unauthorized charges. NYC Transit sends a replacement card in the mail in 10 business days. New Yorkers have embraced the MetroCard discounts and unlimited ride passes. In 2001, 43.2% of all trips were taken using an unlimited ride pass. Use of 7-day passes accounted for 27.3% of trips while the 30-day pass accounted for 11.5% of trips and the one-day pass 4.4% of trips. (Use of the one-day pass has increased from less than 2% of all trips at the beginning of 2000 to over 5% in May 2002.) In addition, 26.9% of trips used bonus MetroCards in 2001. In all, 70.1% of subway and bus trips on New York City Transit used either an unlimited ride pass or a bonus MetroCard in 2001. Non-discounted trips are taken using tokens (10.6%), cash payment on buses (6.6%) or full-fare MetroCards (purchases under $15, including single-ride cards) (12.7%). Response to the fare incentives was much greater than expected by the MTA or other observers. While free transfers were adopted primarily with two-fare zone customers in mind (i.e., riders who take the bus and then subway to work), they were embraced by riders throughout the city. Unlimited ride passes were adopted not only by riders who took enough trips to save money using a pass, but also by riders who were just below the threshold and took more trips using a pass than they would have otherwise. Bus and subway ridership grew at unprecedented rates after the fare discounts and passes were introduced. The fare incentives played a key role in reversing the long-term decline in transit ridership, particularly bus ridership. Many riders said that they began riding buses for the first time in their lives, initially because of the free transfers and then also due to the passes. Riders particularly increased their non-work travel trips for shopping, entertainment, personal business, visiting friends, etc. Non-work transit trips grew by an astounding 62% in the 1990s, in large part due to the fare discounts and passes. In absolute terms, average weekday subway and bus ridership increased from 5.3 million in 1996 to 7.0 million in 2001 – an increase of 1.7 million trips per day, or 31%. Average weekend ridership over the same period increased 49%, from 2.3 million per day to 3.4 million per day. The figure on the next page depicts ridership growth since 1990. The graph distinguishes between ridership changes due to economic changes (estimated based on employment data) and ridership changes due to non-economic factors. Non-economic factors include the impact of fare increases in 1990, 1992 and 1995 and the subsequent fare discounts and passes. Non-economic factors also include the drop in crime in the subway and the city generally, improvements in subway and bus service that are the fruits of the massive capital repair and rebuilding program begun in the early 1980s and changes in the
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city’s make-up such as increased immigration.

As shown in the figure, non-economic factors spurred ridership increases of 2% to 3% a year from 1991 to 1994. Ridership declines in 1990 and 1996 are attributable to fare increases in January 1990 and November 1995. After free transfers were introduced in July 1997, non-economic factors accounted for ridership increases of 4.6%. If one subtracts an underlying growth rate of about 2.5% from non-economic factors, evident in the early-90s, it appears that free transfers by themselves produced approximately 2% incremental growth in ridership. Ridership grew even more quickly with introduction of the bonus on MetroCard purchases over $15 and the unlimited ride passes, reaching over 6% due to non-economic factors in 1998 and the first half of 1999. Notably, rapid increases continued past the initial surge in ridership generated by each new fare incentive. In the second half of 2000 and first half of 2001, transit ridership grew by 6% or more overall, with most of the increases attributable to non-economic factors. It appears that the fare incentives continued to spur increased ridership for at least two years after the one-day pass was introduced in January 1999. The 9/11 attacks and economic decline in the city sharply curtailed ridership growth. Ridership in the first eight months of 2002 was a scant 0.5% higher than for the same period in 2001.
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Had it not been for non-economic factors, however, ridership would have actually declined in 2002. We estimate that in the first half of 2002, economic factors generated a 2.5% reduction in ridership, offset by a 3.1% increase from non-economic factors. Another way to see the countervailing forces is by comparing weekday subway ridership, which is heavily work-related, with bus ridership and weekend subway ridership, which carry primarily non-work trips. In the first eight months of 2002, weekday subway ridership declined 2.0% while increasing by 1.4% on the weekend. Bus ridership increased 2.8% on weekdays and 5.2% on weekends. The experience of the last five years with MetroCard fare discounts and passes holds two important lessons. First, that fare policy can be effective in improving the attractiveness of transit, particularly for non-work trips. The fare policy changes have improved New Yorkers’ mobility and the convenience of using the transit system. Second, fare incentives adopted four to five years ago no longer appear to be fueling further ridership growth. This development raises a timely question: Is there more that can be done? Are there further changes to transit discounts or passes that could further enhance the attractiveness and ease of use of the transit system? Furthermore, can a program be designed that is both effective and affordable in the current budgetary lean times?

Reading Material Ticketing System of HK Metro
Single Journey: Usable for all MTR journeys except AEL, and is valid on date of issue only for a specific journey. Pass ticket gates by inserting the ticket into a slot, if ticket is rejected at the exit gate then go to the customer service counter near platform escalators for re-validation. Octopus card: This smart card allows ease of travel around Hong Kong, reducing the need of preparing coins. Pass ticket gates simply by placing the card on an octopus fare deduct processor; your card will also work if placed inside your bags. As long as you have a usable value of not less than -$35, these may be used on premises like MTR/AEL/KCR, buses, trams, ferries, public payphones, Wilson car-park, various vending facilities and fast-food outlets, LCSD facilities, school campuses, and even private residential buildings (only works if you are the resident of property). Any negative value remaining will be included next time you reload your card [e.g. If you added $100 to a -$10 card, then you will receive $90 instead of $100+]. There are also Personalised Octopus cards which will display your name, photo, and some personal data. Application forms for personalised cards are available
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at most MTR/KCR customer service centres. If you have made 10 MTR trips (excluding AEL) using your octopus card during a week, you are then eligible to receive a free Single Journey ticket to any non AEL stations of your choice. All octopus cards are valid for about three years starting from the date of purchase. Airport Express ticket: This ticket is required for all AEL trips. Octopus cards are also welcome, you can then enjoy a free connection to or from any AEL stations as long as your card has a usable value and you travel on both MTR and AEL within one hour. In addition, no ticket gates are installed at the Airport but you are required to drop your single tickets in the ticket collection box provided on the platform. Valid AEL tickets include:
Single Journey/Same Day Return: Valid on date of issue only, SDR tickets include a free return trip on the same day. Round Trip: Valid for 1 month, include 2 single journeys between Airport to station indicated on ticket. Tourist Pass: Valid from date of your first trip, unlimited one-day MTR rides to any non-AEL stations of your choice. Ticket retainable once expired. Tourist Octopus: Valid from date of your first trip, includes a single AEL journey (depending on the ticket you purchased) plus unlimited 3-day MTR rides to any non-AEL stations of your choice. Ticket retainable once expired.

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Chapter 10 Audible Information Design in the New York City Subway
1 Introduction This paper presents a case study of the New York City subway system as a means to articulate a new methodology for the analysis, simulation, and design of sound information systems. It is a hypothetical exercise,in that the new design we propose for the subway system is not intended for immediate application and would not be practical to implement using the existing equipment. While the New York City subway system is not a complex information environment, it nonetheless provides a very attractive site in which to study sound used as an information medium. At present, the use of sound is uniform across the hundreds of stations and thousands of trains throughout the system. More importantly, an audible signal is a crucial modality for the communication of several key pieces of information, including the success or failure of a turnstile transaction, and the arrival of a train in the station. The New York City subway system thus presents some straightforward audible display design challenges:a few simple pieces of information need to be communicated quickly, unambiguously, and harmoniously by a small number of audible signals. How successful is the existing design at accomplishing this task, and how can it be improved? As we will see below, the existing design fails to reach its potential for informing system users through sound. The design also has important ergonomic and aesthetic shortcomings that will be discussed in greater detail below. Principles from music, information design, interface design, and the emerging field of auditory display science are applied to create a new system-wide sound design. This proposed design will be presented using audiovisual simulations. Our goal is to explore the notion that a unified, musically composed sound design not only improves the experience of subway system users, but also expands the possibilities for communicating critical information through sound. 2 Existing Audio Signals in the New York City Subway System All subway stations posses at least one row of turnstiles, a token booth where subway tokens and Metrocards (electronic fare cards) are sold, and a train platform (track) area. Any station in which the token booth and turnstiles are not immediately adjacent to the track also has a designated “Off-hours waiting area” that is generally within sight of the token booth and turnstiles. 2.1 Turnstiles The New York City subway system uses both token coins and newer electronic farecards (called “Metrocards”) at its turnstiles. Table 1 shows the various conditions and
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signals associated with turnstile transactions. The turnstiles display short electronic text messages that visually indicate the specific user condition, and there is a small speaker inside the card reader that beeps audibly after each card swipe. Example 1: turnstile signals is a recording of the single, double, and triple beep sounds produced by the turnstiles.

2.2 Waiting Area All major subway stations and many smaller ones have waiting areas that are separate from the track platforms.Electronic display signs have been installed in these waiting areas to tell riders when a train is arriving. A text message on the sign indicates the destination of the train and its track designation (local or express). The text display is accompanied by a loud, pulsing whistle sound3 that is the same for all arriving trains. The sound can be heard in Example2: arriving train signal. While these electronic display signs are visible only in the area immediately in front of them, their signals are audible for hundreds of yards through stairways, connecting corridors, and on the train platforms. Many riders respond to the beep signal by breaking into a run in corridors or stairwells in hopes of catching the arriving train, even though the beep does not tell them the direction of the arriving train. Rider responses will be explored in more detail in section three below. 2.3 Train Platforms and Interiors On train platforms, verbal announcements convey information about train delays or routing anomalies when necessary. No attention signal precedes these messages, nor are any other non-verbal audio signals routinely present here. Verbal announcements are also made aboard trains: as a train pulls into each station, the conductor announces the name of the station and any available connections. As the train prepares to leave a station, the conductor announces the next stop and recites a verbal warning to, “Stand clear of the closing doors,” at which time a two-tone alert signal is sounded just prior to the doors closing. Example 3: subway train interior presents the audible signal heard inside the train cars.
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3 User Survey This section presents the responses of subway riders to the existing sound environment. Thirty-six subway riders were asked questions about their awareness of and feelings about the signals present in the system. While this survey is too small to be of statistical value, the rider responses nonetheless help to identify some shortcomings of the system and offer clues as to directions to follow in the redesign. Riders were asked questions about the helpfulness of three main signals in the system: the beeps of the turnstiles, the “train arriving” signal, and the “doors closing” signal. Figure 1 shows a summary of the results.

Respondents were also encouraged to offer opinions and observations about the quality of the sonic experience in the subway system. Regarding the turnstile beeps, four people said they could not tell the difference between the signals for successful and unsuccessful transactions. One rider said, “I hear a sound but I don't know what it means, so I just go through the turnstile and see if it works.” Another person specifically commented that he liked the beeps and noticed that they meant different things. He especially appreciated the warning that his card was low on funds. Several people seemed to equate the “swipe again” signals with the fact that the Metrocards don't work well much of the time. Four of these people used the word “annoying” to describe this signal. In response to the “train arriving” signal, seven people commented that you cannot tell which train is coming from the sound. Five people said that the signal is hard to distinguish from the combined sound of many Metrocards being swiped at the turnstiles. One woman commented, “It took me five years to figure out what the hell that sound is.” Another person said the arrival beeps are too loud. As for the “closing door” signal, five people commented that this sound made them feel safer. Six people called the sound annoying. Several people associated this sound with rush hour and stressful commutes. One person said, “I like it. It keeps me awake in the morning.” Another person liked the musicality of it. One person was particularly
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enthusiastic about all the system’s audible signals. “It's like Pavlonian conditioning,” he said.“[The sounds] tell me my morning is going well.” 4 Analysis of the Existing Sound Design 4.1 Effective Communication The subway system’s sound implementation fails to meet its potential for effective communication in several ways. Overall, there is a lack of coordination among the system’s various sound components. This lack of coordination is evidenced, for example, by the masking effect of the train arrival signal by the turnstile beeps, a predictable result of using sounds within the same 1/3 octave frequency range [4]. As many of the riders surveyed noted, the turnstile beep sounds are indistinct, and the three different signals (single, double, and triple beep) are difficult to distinguish from each other. This may be due in part to the acoustic qualities of the signal, which is a relatively long, unmodulated, steady-state tone with virtually no onset transients in its attack. In the highly reverberant environment of the subway stations, these sounds are difficult to locate directionally, and at busy times, when many turnstiles are sounding at once, the individual beeps seem to merge into a continuos ringing tone. Once this state is reached, it is nearly impossible for a rider to distinguish the sound of his or her own turnstile from the ones around it, and the communication effectiveness of the signal is almost entirely lost. In addition, the turnstile sounds are poorly mapped to the set of conditions they address. As we saw in table 1, above, there are three main possible outcomes of a Metrocard swipe, each requiring a different action on the part of the rider: success (the rider advances though the turnstile), swipe failure (the rider must swipe again), and card failure (the rider must step back out of the turnstile and obtain a new Metrocard). There are three sounds in the existing turnstile implementation, but two of them are mapped to success conditions, while the third is mapped to both swipe failure and card failure. The “train arriving” signal is undifferentiated in its signalling the arrival of different trains at the station, missing an opportunity to inform commuters of whether to rush or relax as they approach the turnstiles. In part 5, we will explore ways of differentiating this signal and of intuitively mapping the variants to the different train arrivals. 4.2 Quality of Experience Despite its use of tonal signals, the New York City subway system sounds decidedly unmusical. The three different signals (turnstile, train arriving, doors closing) all sound within earshot of each other, and yet they bear no meaningful harmonic relationship to each other. The mix that results sounds unintentional, technological and out of tune. The turnstile bank in particular, with its microtonal pitch variations, often sounds like a badly tuned instrument. Since the pitch variation is random and carries no information, we
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perceive it as mildly grating dissonance. The riders’ comments support the notion that while the signals can be informative, they lack aesthetic value; sound in the subway is viewed by riders as entirely utilitarian. 5 Proposal for a New Sound Design In this section, we present design alternatives for the system of signals in the New York City subway system. These new designs attempt to improve on the existing design in the following ways: Improved Communication Effectiveness. This is accomplished by using a wider variety of easily distinguished signals with a logical and intuitive mapping to the conditions enumerated in section 2 above. Improved Listenability. This is accomplished through the use of an expanded sound palette and deliberate composition. A variety of timbres, pitches and rhythms will be used to create a soundscape that is harmonic, varied, and textured. The new design employs variations in rhythm, harmony, and counterpoint to create an environment that is more stimulating, more pleasant, and less stressful than the existing design.The notion of a wind chime, in which distinct tones are struck at unpredictable time intervals, is used to inform the new design. As with a wind chime, the new system contains a group of sounds which sound pleasing individually and in combination with each other. 5.1 Acoustic Criteria Previous studies of auditory signals and warnings [1] provide us with some insights into the design of an effective alert sound. All signals should be constructed of distinctive tonal elements that posses a sharp attack and a rapid decay. The noisy attack and brief tonal body of the sound allow it to be heard distinctly, kept short (reducing overlap and masking), and to be easily localised. Our example uses the sounds of pitched wood bars (marimba) as the basic sonic building block. This sound has a brief, broad-band onset transient that makes it less prone to masking effects than the steady-state tone currently in use [4]. The comparative brevity of the sounds themselves also mitigates masking problems by simply reducing temporal overlap. The proposed turnstile “success” sound, for example, has a half-life of less than 150 ms and has substantially decayed after 200 ms, compared to a steady state duration of 1000 ms for the existing “success” signal. In addition to the selection criteria for individual sound elements, the distribution of the ensemble of tonal, rhythmic and tymbral elements is crucial to the success of the design. Just as an interior designer or architect strives for a unified look when selecting colors and materials, so too must a sound designer select sounds that inform and complement each other and are appropriate for the target space. To this end, different complementary timbres were selected for the train arrival signals (modified flute) and the closing doors signal(bell).
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5.2 Composition A new set of mappings of turnstile swipe results to sounds, presented in table 2, yields more effective communication of useful information to riders. The five sounds represent three basic categories, each of which prescribe a different action for the rider. The “modified” success and swipe failure sounds are each variants on their respective themes; in each case, these signals reprise the original signal (to indicate the action to be taken) but then add an element that expresses an additional warning. Additionally, the signals for arriving trains have been differentiated as shown in table 3. Example 4: Proposed new signals presents the individual sound elements that make up the proposed new sound design.

The proposed sound design was developed through an iterative process of composition, simulation and revision. Simulation techniques were crucial to understanding the implications of various design choices. Simulations took into account the frequency distribution of the various signal-causing events in the subway system, including train arrivals and Metro card swipe outcomes. Figure 2 shows the distribution of 420 Metrocard swipe outcomes as measured at a Manhattan subway station. The amount of time it takes for this many swipes to occur, as well as the number of trains that will arrive and depart in this period, varies widely from station to station and according to the time of day, but the distribution of swipe outcomes is more or less consistent.

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We used Max software to develop a simulation model that takes these distributions into account and allows various parameters to be changed to simulate stations of different sizes and different times of day. Our simulation uses background recordings from actual stations (with turnstile sounds removed), as well as spatialization and reverberation processing of the signals to create a realistic audio field that simulates a bank of turnstiles. Spatialized recordings of the plastic Metrocards being physically swiped, along with the mechanical sounds of the turnstiles cocking forward are coordinated and mixed with the proposed signals to complete the simulation. The simulation helped us to identify the turnstile success sound as the keynote sound in the environment; as the most frequently heard signal, it is the sound in relation to which all other sounds in the environment will be heard. The composition was developed around the fundamental C5 pitch of this signal and an implicit C Major chord, which is the key of the design. All the other signals consist of pitches or pitch combinations that either resolve to or naturally modulate toward C Major. Example 5: Simulation of the propposed new subway station presents the ensemble of signals as they might sound in an actual subway station. 6 Conclusion: Design Guidelines for Audible Information Systems Sound design for any environment must be systemic. Because each sound is heard in relation to others, we must learn to design informational sounds in contextual groups so that signals will not mask each other and so that they will be agreeably distributed in frequency, timbre, rhythm, etc.. While an individual signal in isolation might communicate its message effectively, systems involving multiple signals must be carefully designed in order to avoid acoustical interference and communication ambiguities. Even information environments as simple as the subway system require a systemic approach to sound design and strategic mapping of information to signals in order to make the best use of sound. Audible information signals are generally tonal, and tonal sounds interact musically and are inevitably perceived musically. Recognizing this, we should consider all systems of audible signals to be musical systems, and we should bring to bear the and skills and
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discipline of composers when designing such systems. In sound as in graphic arts, good creative design results not only in a more attractive product, but in a more effectivemeans of communicating the information at hand.

Railway Terms and New Words
methodology hypothetical modality turnstile ergonomic audiovisual two-tone reverberant continuos iterative recordings cocking keynote ensemble acoustical ambiguities n. adj. n. n. adj. adj. adj. adj. n. adj. n. n. n. n. adj. n. 方法学, 方法论 假设的, 假定的, 形式, 形态, 特征 十字转门 人类环境改造学的 视听的 两颜色的, 同色而浓淡不同的 回响的 reverberation 数字低音 重复的, 反复的 录音带, 唱片 压簧杆 基调 [音]合唱 听觉的, 声学的 含糊, 不明确 n. 反响, 回响

Reading Material
Variations of the Letter M
Most metros have logos or symbols to mark their station entrances, rolling stock and printed matter such as maps or tickets. Since most metros around the world are indeed called 'metros' (only few are called subway, underground, U-Bahn, T-bana or something else), many metro logos are more or less fancy variations of the letter M. There are different kinds of metro logos. In some cities a logo stands for the metro system itself, while in other cities only logos are found which represent the companies that are operating one or more metro lines. So there may be more than one logo in use in one city while in another a logo can consistently stand for the system or even for several metro systems within a country. Examples for country-wide use of logos are found in Germany,
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Italy, Spain and Russia. All German metros use a blue U logo and all German S-Bahn-type suburban railways bear a green S logo. Most Italian cities use a red M logo for metros. All Spanish suburban railways have the same red C logo. Many Russian metro cities are using derived versions of the same sloped red letter M of the Moscow metro. Due to these differences in usage, the following list can merely give a rough overview. If in a city a logo for the metro system itself is in use, this list will prefer it over any company logos and omit the latter.

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