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The goal of a network design problem (NDP) is to make optimal decisions to achieve a certain objective such as minimizing total travel time or maximizing tolls collected in the network. A critical component to NDP is how travelers make their route choices. Researchers in transportation have adopted human decision theories to describe more accurate route choice behaviors. In this paper, we review the NDP with various route choice models: the random utility model (RUM), random regret-minimization (RRM) model, bounded rationality (BR), cumulative prospect theory (CPT), the fuzzy logic model (FLM) and dynamic learning models. Moreover, we identify challenges in applying behavioral route choice models to NDP and opportunities for future research. 相似文献
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Increased speed variation on urban arterials is associated with reductions in both operational performance and safety. Traffic flow, mean speed, traffic control parameters and geometric design features are known to affect speed variation. An exploratory study of the relationships among these variables could provide a foundation for improving the operational and safety performance of urban arterials, however, such a study has been hampered by problems in measuring speeds. The measurement of speed has traditionally been accomplished using spot speed collection methods such as radar, laser and loop detectors. These methods can cover only limited locations, and consequently are not able to capture speed distributions along an entire network, or even throughout any single road segment. In Shanghai, it is possible to acquire the speed distribution of any roadway segment, over any period of interest, by capturing data from Shanghai’s 50,000+ taxis equipped with Global Positional Systems (GPS). These data, hereafter called Floating Car Data, were used to calculate mean speed and speed variation on 234 road segments from eight urban arterials in downtown Shanghai. Hierarchical models with random variables were developed to account for spatial correlations among segments within each arterial and heterogeneities among arterials. Considering that traffic demand changes throughout the day, AM peak, Noon off-peak, and PM peak hours were studied separately. Results showed that increases in number of lanes and number of access points, the presence of bus stops and increases in mean speed were all associated with increased speed variation, and that increases in traffic volume and traffic signal green times were associated with reduced speed variation. These findings can be used by engineers to minimize speed differences during the road network planning stage and continuing through the traffic management phase. 相似文献
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Forng-Chen Chiu Wen-Chuan Tiao Jenhwa Guo 《Journal of Marine Science and Technology》2007,12(4):203-217
It is well known that the hydrodynamic responses of a high-speed vessel traveling in regular head waves of even moderate wave
height can show significant nonlinear behavior, and so linear statistical techniques become insufficient for predicting the
statistics of responses in irregular waves. On the other hand, it has been shown that an approximate third-order Volterra
model is applicable to handling the statistics of some nonlinear seakeeping problems, such as motions and vertical hull girder
loads. In the present study, the focus is on the nonlinear behavior of the pressure responses of the hull surface, especially
on the pressures acting on alternately wet and dry areas near the waterline and on the bow zone with high deadrise angles
that may be subject to slight impact and water pile-up effects. To clarify the validity of applying Volterra modeling to this
problem, a series of experiments in regular and irregular head waves were carried out, and approximate third-order and fifth-order
Volterra models with the proposed algorithm for finding frequency response functions (FRFs) were applied as a means of validation.
In the present article, the first part of the validation was performed using experimental data in regular waves. It was confirmed
that the third-order Volterra model has adequate accuracy to simulate deterministically the variation of pressure responses
in regular waves of different wave steepness up to a wave amplitude to wavelength ratio of 0.01 even for the highly nonlinear
pressures acting on the above-mentioned areas of the hull surface. 相似文献
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建立了结构系统广义可靠性分析模型。根据随机变量可能同时具有随机性和模糊性的特点,分别提出了模糊强度—随机应力、随机强度—模糊应力和模糊强度—模糊应力情况下的模糊可靠性分析方法。同时,建立了结构系统为独立单元部件串联或并联组成的模糊可靠性分析模型。考虑到不同模糊随机变量组合下的可靠性积分一般不存在解析解的情况,提出了用仿真法计算可靠度数值解,并阐述了数值仿真的基本原理和步骤。通过实例介绍了方法的具体运用。 相似文献
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