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111.
This article presents a route choice model for public transit networks that incorporates variables related to network topology, complementing those found in traditional models based on service levels (travel time, cost, transfers, etc.) and users’ socioeconomic and demographic characteristics (income level, trip purpose, etc.). The topological variables represent concepts such as the directness of the chosen route and user knowledge of the network. For both of these factors, the necessary data is endogenous to the modelling process and can be quantified without the need for information-gathering beyond what is normally required for building route choice models. Other novel variables in the proposed formulation capture notions of user comfort such as vehicle occupancy rates and certain physical characteristics of network stations. We conclude that these new variables significantly improve the explanatory and predictive ability of existing route choice specifications.  相似文献   
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The objective of this study was to obtain a better understanding of carbon monoxide (CO) concentrations immediately upwind of urban roadways, the “local background” values, and how these concentrations depend upon the surrounding traffic and the general meteorology. Measurements were made at seven sites in Seattle, WA during the winter of 1993. Local background CO concentrations were characterized by an absence of short term fluctuations, a steady buildup during the 3 p.m. to 11 p.m. period, and a lack of spatial gradients in the 8-h average values. Distinctly different log-normal distributions of the 8-h averages were observed for “trafficked” sites versus “urban park” sites, with mean values of 1.6 and 1.0 ppm respectively. A simple regression model was developed to predict the local background CO that includes distance from roadway, average daily traffic of nearby roadways, and the frequency of occurrence of low wind speeds (R2 = 0.74; F = 170).  相似文献   
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Most modal split models have been based on the assumption of rational behaviour in an individual's choice evaluation of the generalised costs of modal alternatives. This paper integrates conceptual and empirical information from a wide range of sources and points towards an alternative way of looking at modal choice. The main conclusion is that the car is usually perceived as the superior mode for vehicular travel and that the potential user is committed to its use largely through the act of purchasing it. The conceptual structure of a sequential modal split model is outlined as one that is based on a four-stage decision-making framework which considers the role of learning and habit-formation. In the conclusion, the implications of this approach are considered in terms of the conventional modal split and trip generation submodels, and certain policy measures are assessed.  相似文献   
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In this article the nature of information in the ocean shipping industry is analysed and an information system for processing industry data is outlined. The system collects and verifies data from many sources and supplies input for the decision-maker, in a comprehensible format, based on facts and not on estimates. Typical applications of the system are discussed and their impact in several cases is presented.  相似文献   
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A new assignment principle for traveler behavior in an urban network is described which is based on empirical findings in the theory of travel budgets. It characterizes the distribution of travelers, demand, and modal split. It treats all travel decisions (whether to travel, where to go, how to get there) and the important costs (time and money) in a single, unified way. A numerical technique is proposed and it is applied to several examples to illustrate qualitative features.  相似文献   
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The authors of this paper make use of computer simulation techniques as a means of investigating the problems associated with minimizing a ship's turn-round time.  相似文献   
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A sample of 1000 households completed a questionnaire regarding difficulties encountered purchasing gasoline during the week 4–10 June 1979 and whether difficulties encountered purchasing gasoline affected household automobile tripmaking. Results of this survey were analyzed and it was found that the frequency of reporting purchasing difficulties varied directly with household income and inversely with the age of the household. The frequency of reporting that purchasing difficulties affected automobile trip-making varied directly with household income and inversely with the number of adults in the household. Further, although individual household response was highly sensitive to socioeconomic characteristics, the overall response to the survey would not have differed significantly had the socioeconomic mix of households been different.  相似文献   
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