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91.
机场地面集疏运系统是机场发展的重要支撑,交通需求预测是进行机场集疏运交通规划的前提。笔者以四阶段预测的基本原理为基础,结合机场集疏运需求特点,对预测的整体思路、方法、步骤和内容等进行详细分析,优化调整出行分布、方式划分预测模型,并以南京禄口国际机场为实例进行了预测。研究成果对国内同类大型机场的集疏运需求预测具有借鉴和参考价值。 相似文献
92.
Shenzhen Port (SZP), once a negligible local port, has risen dramatically to a world-leading container port and an “equal” player with Hong Kong Port (HKP). Will this market share reallocation continue, or will equilibrium be eventually realized for HKP to prosper continuously? We examine the relationship between these two ports to answer this question. We propose a new transformation method to describe the growth of container cargo transport demand, define the quantitative measures of the competition relationship and port competitiveness, and present a rigorous analytical framework with econometric tests and models to understand the true relationship between HKP and SZP. Direct empirical tests suggest that SZP complements HKP; however, the two ports exhibit strong competition when the effect of demand growth is excluded. Considering transshipment separately, we find that the impact of SZP on HKP is negative in transshipment but complementary in direct shipment. We may conclude that HKP does not affect SZP, whereas SZP has competitive power over HKP. These results are consistent with the findings of some previous theoretical studies. 相似文献
93.
94.
基于非集计与弹性联合模型的交通需求分析 总被引:2,自引:0,他引:2
随着我国交通事业的蓬勃发展,人们对交通方式的需求正在不断发生变化。基于科学研究的交叉性和外延性,将不同研究领域已经基本成熟的模型,即微观经济学中的费用效益弹性理论模型和交通方式分布中的非集计模型(Logit模型)有机地结合并融为一体,得到一种联合模型,使其更容易将数据定量化、具体化。通过这个联合模型来分析交通需求并将与交通需求相关的因素进行对比,得出交通因素发生变化对交通需求者和供给者的影响。 相似文献
95.
96.
该文以我国城市道路交通管理规划的现状为出发点,提出了城市道路交通管理规划是一项重要课题,阐述了交通管理规划的目的、基本内容及三个层次,论述了交通需求预测的分析方法及模型。最后结合兰州市道路交通管理规划的框架与实施情况,分析其主要成果及产生的社会经济效益。 相似文献
97.
根据地震环境下不同恢复阶段的社会经济活动及交通系统特性,对传统交通预测四阶段法———出行产生、出行分布、方式划分、交通分配的宏观模型进行了修正,讨论了不同模型的参数变化趋势,建议了参数的调整原则及方法,进而以修正四阶段法为基础进行震后交通需求预测。该方法简便易行,预测得到道路通行能力、流量、负荷度和平均运行时间等多个指标,为城市交通系统防灾规划提供决策依据。最后,结合我国东南沿海某城市的工程实践,有针对性的进行了应用和验证。 相似文献
98.
Markets for transport are often characterised by unequal demand in both directions: every morning during peak hours the trains are crowded while moving towards the direction of large cities, whereas they may be almost empty in the other direction. In this paper we discuss the implications of these imbalances for price setting of transport firms. From the viewpoint of economic theory, two regimes can be distinguished: one where – owing to price discrimination – the flows are equal, and one where unequal flows are the result. Special attention is paid to the case where the transport firm does not apply price discrimination, as is the case with most railway firms in Europe. We find that in the case of substantial joint costs, the introduction of price discrimination not only leads to an increase of profits, but also to positive effects on consumer surplus. This result differs from the standard result in the literature on industrial economics. The standard result purports that with linear demand functions price discrimination has a negative impact on the welfare of the average consumer and that this negative impact dominates the positive effect on profits of the producer. 相似文献
99.
Rail access to airports is becoming increasingly important for both train operators and the airports themselves. This paper reports analysis of inter-urban rail demand to and from Manchester and Stansted Airports and the sensitivity of this market segment to growth in air traffic and the cost and service quality of rail services. The estimated demand parameters vary in an expected manner between outward and inward air travellers as well as between airport users and general rail travellers. These parameters can be entered into the demand forecasting framework widely used in the rail industry in Great Britain to provide an appropriate means of forecasting for this otherwise neglected market segment. The novel features of this research, at least in the British context, are that it provides the first detailed analysis of aggregate rail flows to and from airports, it has disaggregated the traditional generalised time measure of rail service quality in order to estimate separate elasticities to journey time, service headway and interchange, and it has successfully explored departures from the conventional constant elasticity position. 相似文献
100.
This paper develops a conceptual framework for the generation of activity and travel patterns in the context of more general
structures and presents an integrated model system as a step toward development of an improved travel demand forecasting model
system. We propose a two-stage structure to model activity and travel behavior. The first stage, the stop generation and stop/auto
allocation models, consists of the choices for the number of household maintenance stops and the allocation of stops and autos
to household members. The second stage, the tour formation model, includes the choices for the number of tours and the assignment
of stops to tours for each individual, conditional on the choices in the first stage. Empirical results demonstrate that individual
and household socio-demographics are important factors affecting the first stage choices, the generation of maintenance stops
and the allocation of stops and autos among household members, and the second stage choices, the number of tours and the assignment
of stops to tours.
This revised version was published online in June 2006 with corrections to the Cover Date. 相似文献