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Transportation and Traffic Congestion,Wang Yantian Xu Guodong He Haohong,Introduction:,The movement of people and goods within a city is a special area of transportation with unique characteristics. Several modes of transportation compete or complement each other in providing transportation services in the city. A dense network of transportation services affects the efficiency of operation in an urban area that causes traffic congestion. There is a direct connection between transportation and the city growth. Pollution and congestion are additional costs related to transportation. Effect of pollution are two fold: negative effects on health of humans, animals andvegetation and expenditure for pollution reduction and cleanup. Congestion produces wasted productive time due to the extended travel time.,Several approaches,Private automobile: This involves drive alone, drive with a passenger or passengers in a private car. Carpooling is the organized commute with a minimum of two people in the vehicle. Most common form of carpooling is the intra-household where two or more member of the household utilize same car. Carpooling between co-workers is less popular despite its potential to reduce congestion on roadways. Van Pooling: This is voluntary or company Organized commute to work. Either a group of individuals agree to lease a van from a provider or company provides transportation to and from work. In several areas where there is severe congestion on the roadways, pressure is applied on the employers to reduce the number of trips generated by their employees through the institution of car and van pools. This reduces congestion on the roadways. Taxis: These are either owner operated or privately owned that provide transportation to the general public. Major markets for taxis are tourists, visitor, and business people. Also for people in a hurry and people who do not need a car at their destination tend to hire taxi service.,Buses: These usually are publicly owned mass transit system used for schoolchildren transportation, labor transportation and company sponsored workers transportation from the suburbs to the work places. These can reduce congestion considerably if used by the public on a regular basis. Light Rail, Rail Rapid Transit System, commuter Railway, Air and Water Services: All these modes help reducing the traffic congestion on the roadways in the cities. Park and ride where individuals park their vehicle and then ride public transportation, van pools or car pool are made available also.,Lets see a video,Not only in Beijing,Tai Yuan,Wu han,GUANG DONG,Jakarta, The Republic of Indonesia,Everywhere.,Two Representations of Urban Network System,Primal:,intersections (or settlements) are turned into nodes and roads (or lines of relationship) are turned into edges.,Dual:,roads are turned into nodes, intersections are turned into links between the corresponding nodes.,Two Representations of Urban Network System,Primal Graphs of the 6 cities,dual graphs of the 6 cities,Primal,intuitive, the value of distance can be easily associated to edges. But it can not characterize the common notion of “main roads” in urban traffic systems. It violates the intuitive notion that an intersection is where two roads cross, not where four roads begin.,Dual,one can have many “conceptually countless” edges for each node. This leads to the recognition of scale-free behavior for the degree distribution of urban street networks.,Compare Primal & Dual,Traffic Problem:,At present about millions trips are made by the Chinese people per day. Many of these trips are made by private vehicles. Heavy trucks carry freight into and out of the cities and smaller trucks are used for the local deliveries. Many cities have ports and airports which are the primary entry or exit points for passengers and cargo originating from or destined to a broad area. All these functions generate substantial traffic loads and congestions to the urban road networks. Several transportation problems plague contemporary urban areas, the most prevalent being traffic congestion. Traffic congestion is created on fixed capacity road networks when traffic grows above a certain threshold, after which the level of service deteriorates to unacceptable levels. Capacity of roadway system is to a large extent determined by transportation system characteristics and policies such as geometry, signalization characteristics, and traffic management restrictions. The capacity is also determined by the driving habits of the drivers.,Whats wrong?,1.Traffic Growth: Traffic congestion is directly related to the traffic growth. There are four components of traffic growth. 2.The natural growth of the population: As the population grows, more vehicles are on the road producing congestion unless roadways are improved 3.Location Patterns: This is due to spatial distribution of residence, work, shopping, and entertainment places.,4.Transportation System, Characteristics and Polices: Speed limits imposed by city and state, signaling service wait times, establishment of car pool, bus lanes etc. affects the traffic growth also. The transportation behavior of people is affected by the characteristics and norms of individuals and households, which along with the locational patterns of places ad activities are affected by the evolution of the society, economy and the technology at a regional and national level.,another video,Effects of Traffic Congestion:,Loss of productive time Loss of fuel Increase in pollutants: There two ways the pollutants increase. One due to more gas burnt due to the traffic congestion, and second there is more time is spent when the engine is idle or stop and go traffic. Increase in wear and tear of the automobile engines High potential for traffic accidents Slow and insufficient emergency response Peoples moods are often affected, which has negative impacts on productivity at work and on personal relationship Road rage incidences.,Effect of traffic congestion are multiple.,Solution strategies,Pricing: This is a method of making the people to drive less. The pricing can be implemented via roadway use toll, parking charges, mass transit fares, fuel surtaxes, and area wide roadway use pricing. All these generates some revenue for the city. Objectives of pricing: Provision of disincentives for using private automobiles through higher cost of utilization, e.g., parking pricing. Provision of disincentives for using private automobiles without passengers in vehicle except the driver encouraging the carpooling. Provision of funds to expand mass transit systems this includes the fuel and other auto specific surtax to fund development of new public mass transit systems. Development of fare structure favoring spreading the morning and evening peak on Public transportation system, i.e., offering lower fairs at off peak hours etc.,There are three categories of solution to traffic congestions,Management and Policy: Measurement of ramp metering that controls flow entering freeway so that freeway operates at the optimal flow levels. City zoning that may enable authorities to control number of major traffic generators along congested corridors. It also allows the authorities to allocate future plans for the transportation networks. Enforcement of balanced employment and residential development that has the potential to reduce traffic. Flex time of staggered work hours that may help spreading the morning and evening peaks of travel demand. Employ restricted access according to which private or all vehicles are prohibited from certain streets or urban sections such as the transit ways and pedestrian malls etc. Regulation of parking, delivery zones, and timesof certain operations, aimed at avoiding chaotic conditions such as multiple parallel parking, bottle necks and other hazards. Demand responsive public transportation that is a nonscheduled passenger service aimed at helping people with mobility problems or serving low density areas of the city where employing a full public service will be wasteful. Incentive strategies aimed at reducing number of automobiles on the roads and improving efficiency of public services. High Occupancy Vehicle (HOV) lanes, bus only lanes and incentive to use car or van pools.,Future transportation system,Another another video,Glossary,1. 交通规则 traffic regulation 2. 路标 guide post 3. 里程碑 milestone 4. 停车标志 mark car stop 5. 红绿灯 traffic light 6. 自动红绿灯 automatic traffic signal light 7. 红灯 red light 8. 绿灯 green light 9. 黄灯 amber light 10. 交通岗 traffic post 11. 岗亭 police box 12. 交通警 traffic police 13. 打手势 pantomime 14. 单行线 single line 15. 双白线 double white lines 16. 双程线dual carriage-way 17. 斑马线 zebra stripes 18. 划路线机 traffic line marker 19. 交通干线 artery traffic 20. 车行道 carriage-way 21. 辅助车道 lane auxiliary 22. 双车道 two-way traffice 23. 自行车通行 cyclists only,24. 单行道 one way only 25. 窄路 narrow road 26. 潮湿路滑 slippery when wet 27. 陡坡 steep hill 28. 不平整路 rough road 29. 弯路 curve road ; bend road 30. 连续弯路 winding road 31. 之字路 double bend road 32. 之字公路 switch back road 33. 下坡危险 dangerous down grade 34. 道路交叉点 road junction 35. 十字路 cross road 36. 左转 turn left 37. 右转 turn right 38. 靠左 keep left 39. 靠右 keep right 40. 慢驶 slow 41. 速度 speed 42. 超速 excessive speed 43. 速度限制 speed limit 44. 恢复速度 resume speed 45. 禁止通行 no through traffic 46. 此路不通 blocked,Glossary,47. 不准驶入 no entry 48. 不准超越 keep in line ; no overhead 49. 不准掉头 no turns 50. 让车道 passing bay 51. 回路 loop 52. 安全岛 safety island 53. 停车处 parking place 54. 停私人车 private car park 55. 只停公用车 public car only 56. 不准停车 restricted stop 57. 不准滞留 resticted waiting 58. 临街停车 parking on-street 59. 街外停车 parking off-street 60. 街外卸车 loading off-street 61. 当心行人 caution pedestian crossing 62. 当心牲畜 caution animals 63. 前面狭桥 narrow bridge ahead 64. 拱桥 hump bridge 65. 火车栅 level crossing 66. 修路 road works 67. 医院 hospital 68. 儿童 children 69. 学校 school,70. 寂静地带 silent zone 71. 非寂静地带 silent zone ends 72. 交通管理 traffic control 73. 人山人海 crowded conditions 74. 拥挤的人 jam-packed with people 75. 交通拥挤 traffic jam 76. 水泄不通 overwhelm 77. 顺挤 extrusion direct 78. 冲挤 extrusion impact 79. 推挤 shoved 80. 挨身轻推 nudging 81. 让路 bive way 82. 粗心行人 careless pedestrian 83. 犯交通罪 committing traffic offences 84. 执照被记违章 endorsed on driving licence 85. 危险驾驶 dangerous driving 86. 粗心驾车 careless driving 87. 无教员而驾驶 driving without an instructor 88. 无证驾驶 driving without licence 89. 未经车主同意 without the owners consent 90. 无第三方保险 without third-party insurance 91. 未挂学字牌 driving without a “L“ plate 92. 安全第一 safety first 93. 轻微碰撞 slight impact 94. 迎面相撞 head-on collision 95. 相撞 collided 96. 连环撞 a chain collision 97. 撞车 crash 98. 辗过 run over 99. 肇事逃跑司机 hit-run driver 100. 冲上人行道 drive onto the pavement,THANK YOU,
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