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181.
182.
随着社会的发展,社会分工的细化和人才的需要,远程职业教育的重要性愈加体现,其作为远程教育体系结构中的薄弱环节将会被大力发展。该文就远程职业教育的服务对象、教学实施和质量控制等问题阐述了一定的观点。 相似文献
183.
提出采用双线性模型预测公路客运量。预测模型包含时序自回归项、线性回归项和双线性项三部分。为了研究模型参数的时变特性,将公路客运量预测分为模型参数的预测和在此基础上的客运量预测,采用多层递阶方法计算模型的时变参数,然后进一步分析拟合参数的变化曲线,计算后续时段的参数预测值,并以此进行公路客运量预测。实例分析表明,双线性动态预测模型能很好地反映公路客运量的发展特性,具有较高的预测精度和实用价值。 相似文献
184.
信息技术的发展为公路运输业对社会提供优质服务创造了条件,建立公路客运综合信息平台不仅技术上可行,也有其必要性。通过分析公路客运信息化的现状,研究并设计了客运综合信息平台的系统结构、系统功能和系统目标,并对系统的实施和前景进行了探讨。 相似文献
185.
186.
针对目前国内外长大隧道火灾救援这一前沿问题,从隧道火灾救援的组织规划、火灾情况下的消防系统、火灾情况下的通风组织、火灾情况下的行车组织等4个方面进行了分析和研究,结合秦岭终南山公路隧道的特点,制定出了切实可行的救援组织实施流程、安全可靠的消防系统、最有利的通风风速和风流方向,以及快速逃离火灾现场的行车方式。 相似文献
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188.
Avishai Ceder 《Transportation》2006,33(2):133-152
A predominant observation in Hong Kong is the continuous loss in ferry patronage. There are two main reasons for this: poor
level-of-service and better competitors. New roads, bridges, and tunnels are serving the buses, and to some extent the railways;
whereas the investment in ferry terminals is relatively at a lower level. On the one hand, there is no need to promote the
ferries in a free market environment; but on the other hand, the ferries have the best safety record, can only relieve some
traffic congestion and need water access that is one of the characteristics of Hong Kong. The goal of this paper is to design
a planning approach combined with an evaluation procedure on how to make the best use of the existing water and pier resources
in Hong Kong through the provision of commercially viable ferry services. The approach used covers the impact of future developments
planning up to 2006 comprising all public transport modes in Hong Kong (heavy rail, metro, bus, and ferry). The planning tool
is based on a newly developed multi-objective evaluation method in order to assess the ferry routes with scientific, practical,
and simplified analyses for future use. This assessment is applied to the existing ferry routes and candidate routes and can
also be carried out on an individual route basis or on a given set of routes. The objective functions set forth analytically
in the evaluation method take into account the interests of the three participants: the passengers, the operators and the
government. The proposed ferry network design formulation and the suggested new ferry routes will have a positive impact on
changing the ferry system’s image in Hong Kong. 相似文献
189.
指出了内燃机油底壳上放油螺丝在使用中存在的问题 ,分析由此而引起的后果 ,提出了排放失效机油过程中所需达到的要求 ,介绍了内燃机机油专用放油阀门 相似文献
190.
Elasticities for taxicab fares and service availability 总被引:1,自引:0,他引:1
This study utilizes a unique dataset from New York City to examine the effects of taxi fare increases on trip demand and the availability of taxi service. The elasticity of trip demand with respect to fares is estimated to be –0.22; the elasticity of service availability with respect to the taxi fare is 0.28; and the elasticity of service availability with respect to total supply of service is near 1.0. These results have important implications for taxi regulatory decisions. First, fare increases do substantially increase industry revenues but at a lesser rate than the percentage increase in the fare. The implication for policy-makers is that fare elasticities must be carefully considered to obtain desired improvements in drivers' earnings. Second, service availability -- an important aspect of service quality that is generally overlooked during fare policy debates -- should be a central consideration in fare setting, given the considerable impact of fares on availability. Finally, where the supply of cabs needs to be expanded, the number of cabs can be significantly increased without harming the revenue stream of existing operators. This finding alleviates a major industry objection to issuing additional taxicab licenses. 相似文献