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931.
The fare of a transit line is one of the important decision variables for transit network design. It has been advocated as an efficient means of coordinating the transit passenger flows and of alleviating congestion in the transit network. This paper shows how transit fare can be optimized so as to balance the passenger flow on the transit network and to reduce the overload delays of passengers at transit stops. A bi‐level programming method is developed to optimize the transit fare under line capacity constraints. The upper‐level problem seeks to minimize the total network travel time, while the lower‐level problem is a stochastic user equilibrium transit assignment model with line capacity constraints. A heuristic solution algorithm based on sensitivity analysis is proposed. Numerical example is used to illustrate the application of the proposed model and solution algorithm. 相似文献
932.
William H. K. Lam Jing Zhou Zhao-han Sheng 《Transportation Research Part B: Methodological》2002,36(10)
This paper proposes a new formulation for the capacity restraint transit assignment problem with elastic line frequency, in which the line frequency is related to the passenger flows on transit lines. A stochastic user equilibrium transit assignment model with congestion and elastic line frequency is proposed and the equivalent mathematical programming problem is also formulated. Since the passenger waiting time and the line capacity are dependent on the line frequency, a fixed point problem with respect to the line frequency is devised accordingly. The existence of the fixed point problem has been proved. A solution algorithm for the proposed model is presented. Finally, a numerical example is used to illustrate the application of the proposed model and solution algorithm. 相似文献
933.
In this paper, reasonable paths in transit networks are defined as possible paths that satisfy the acceptable time criterion and transfer‐walk criterion. A recursive algorithm for finding all of the reasonable paths in a transit network that does not involve a rapid increase in program run‐time with network size is presented. Realistic transit networks in Hong Kong and Guangzhou were selected as case studies of the different phases of the development of a trip planning system. Transport planning practitioners and potential users were invited to test the system to evaluate its performance. The results of the prototype evaluation were satisfactory, and the viability of the system as a useful tool for supporting decision‐making has been confirmed by the positive feedback that was obtained from survey questionnaires. 相似文献
934.
G. Čelechovský 《Transportation》1972,1(2):151-176
Etarea is a planned satellite town for Prague, the capital of Czechoslovakia, located some 10 km from the outskirts of the capital. Its projected population of 135,000 will live in 13 residential areas, each of which will have its own retail centre in addition to the main retail centre.The plans for Etarea incorporate a unique approach to the related problems of the storage and distribution of goods within urban areas. All incoming goods will be delivered by road or rail, and possibly in the future by water, to a central storage complex. Goods for the retail trade are distributed from this central store by automated trains pulled by battery-powered trucks, each train having a capacity of 8.75 tons. The trains, which run in a network of underground tunnels, 2 \sX 2.5 meters in cross section, are guided by an optical sensing system. The underground network comprises 3 main routes with branches serving the individual centres. Secondary storage facilities are planned for each of the 14 retail centres where unit loads received from the main storage centre are subdivided for retail sale.One of the proposed methods of retail distribution provides for the fully automated delivery of goods from the retail centres direct to the consumer's household. This is accomplished by means of a pneumatic tube system similar to that used for handling cash in some large stores. Orders will be placed by dialling the code number assigned to the required item, given in a catalogue of available goods. Provided that the customer's account is in credit the order will be accepted and the goods automatically dispatched from the local centre; delivery is estimated to take between 2.5 and 11.5 minutes depending on the distance of the customer's house from the centre. The same system is utilised for the delivery of regular orders for such items as newspapers and magazines as well as for mail and for the the removal of household refuse. In addition to the automated system each retail centre will also have over-the-counter, self-service and slot machine facilities for the sale of goods.All proposals for goods storage and distribution planned for Etarea are based on existing technologies. 相似文献
935.
When passenger terminal layout is being decided, one of the important aspects to consider is how the passenger orients himself during his visit to the terminal and his movements through it, i.e. terminal orientation. Among other things, this terminal characteristic results from visibility, or the visual connectivity between elements and spaces. The paper proposes an amendment and modification to the known method for the quantitative evaluation of terminal orientation which uses an oriented network to describe the connectivity of elements (terminal orientation). The amendment and modification of the method consists of proposing that during evaluation only visual connections that have functional meaning should be considered, rather than all visual connections. A further modification is the introduction of different weights for different connections. The example presented in the paper considers an airport terminal building. 相似文献
936.
937.
用地高辛配基(Digoxingenin)分别标记,制备HPV-6、HPV-11、HPV-16及HPV-18的DNA探针,应用核酸杂交技术,对37例宫颈癌活检组织DNA作了检测,各型HPVDNA的检出率为:HPV-60%(0/37)、HPV-112.7(1/37)、HPV-1667.5%(25/37)、HPV-1813.5%(5/37),联合应用HPV-16和HPV-18探针共同检测结果为81%(30/37)。结果显示:我国宫颈癌的发生与HPV感染密切相关,联合应用高危型HPV探针可提高检出率并可省时、简便。DIG标记探针因具特异、敏感、安全和简便诸特点,宜推广应用。 相似文献
938.
露石水泥混凝土路面关键技术研究 总被引:17,自引:2,他引:17
研究了露石水泥混凝土路面铺筑过程中必然要遇到的材料选择、冲洗时间、成熟度、双层铺筑混凝土强度等关键技术问题,分析了冲洗时间、成熟度的主要影响因素,发现温度越高,冲洗时间越早,最早冲洗时间与最迟冲洗时间有较大的间隔,常温下可达十多个小时,温度升高,间隔减小,成熟度随温度的升高而增大,相隔一定时间分两层振捣的水泥混凝土试件强度与一次振捣的水泥混凝土试件强度基本相同。结果表明:成熟度指标、试验法是评价、检测露石工艺性质的有效手段,两层铺筑方法是降低此种路面成本的有效途径。 相似文献
939.
ATS仿真培训系统的设计与实现 总被引:8,自引:2,他引:8
利用仿真技术对员工进行职业培训已越来越广泛地得到认可.从上海市地铁1号线ATS系统实际出发,综台现代仿真理论、DCOM和ActiveX等技术,设计一种基于分布式三层结构的城轨ATS仿真培训系统解决方案.重点介绍系统的体系结构,以及该仿真培训系统的各功能模块. 相似文献
940.
地铁整合建设与广州市可持续发展 总被引:3,自引:0,他引:3
从城市可持续发展的角度出发,探讨了地铁与城市发展、地铁经济、交通网络、地下空间、地铁文化之间的整合建设.今后地铁开发应该做好规划,实施综合开发,改善乘车环境,充分发挥地铁对可持续发展的作用. 相似文献