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201.
Those designing surveys and producing data have always been concerned about its quality. The increasing stringency of the financial constraints which affect public authorities and the increased scope of involvement in the regulation of urban travel has led us to pay even greater attention to the quality of data. This issue is frequently covered in the literature on survey methods. However, comparisons between different survey methods are more rarely conducted. The decision to conduct such an analysis is partly the result of the development of telephone use to the detriment of other survey modes in many countries and also the development of Computer-Aided Telephone Interviewing (CATI) which facilitates the running and monitoring of the survey.This paper examines several aspects of this question in order to compare the performance of telephone and face-to-face interviews. The first aspect is the representativeness of the sample, and therefore relates mainly to the issue of nonresponses and the choice of a sample base. The second concerns the accuracy of the information and involves the choice of a survey area and the recording of all trips, including short-distance travel. Finally, the quality of data is obviously determined by the quality of the responses given by those interviewed.The answers we give frequently depend on the objective of the surveys, which leads us to put forward a table which summarizes the performance of telephone and face-to-face interviews on the basis of the main objective of the survey. Broadly, the telephone seems to be the favoured tool for surveys in the area of transport planning and surveys which aim to provide data for forecasting models, mostly on the grounds of cost. However, face-to-face techniques are often preferred for surveys which aim to discover and analyze the factors which explain individual travel behaviour. 相似文献
202.
203.
美海军协同作战系统的组成与发展 总被引:1,自引:0,他引:1
协同作战系统是美国海军实现网络中心作战思想的关键环节,该系统的投入使用将有效提高航母战斗群的对空防御作战能力。本文对该系统的组成,功能及发展趋势进行介绍和分析。 相似文献
204.
205.
本市以天津城市主干道卫津路拓宽改造工程为例,论述城市道路经济效益计算方法。按全天高峰小时、非高峰小时,分别计算机动车和非机动车的运营成本、时间价值及事故费用,采用有、无项目对比法.进行经济效益计算。经济效益中以车辆行程时间延误与路口时间延误的节约作为主要效益。 相似文献
206.
207.
Prediction of fatigue life and estimation of its reliability on the parts of an air suspension system 总被引:1,自引:0,他引:1
K. J. Jun T. W. Park S. H. Lee S. P. Jung J. W. Yoon 《International Journal of Automotive Technology》2008,9(6):741-747
Air suspension systems have been implemented in various commercial vehicles, such as buses and special purpose trucks, because
of the comfortable ride and easy height control. An evaluation of the durability of vehicle parts has been required for service
life and safety starting in the early stages of design. The cyclic load applied to the vehicle can cause fatigue failure of
parts, such as the suspension frame. This paper presents a method to predict the fatigue life of the suspension frame at the
design stage of the air suspension system used in a heavy-duty vehicle. To estimate the fatigue life using the SN method,
the Dynamic Stress Time History (DSTH) is necessary for the part of interest. DSTH can be obtained from the results of the
flexible body dynamic analysis using the Belgian road simulation and the Modal Stress Recovery (MSR) method. Furthermore,
the reliability of the predicted fatigue life can be evaluated by considering the variations in material properties. The probability
and distribution of the expected life cycle can be obtained using experimental design with a minimum number of simulations.
The advantage of using statistical methods to evaluate the life cycle is the ability to predict replacement time and the probability
of failure of mass-produced parts. This paper proposes a rapid and simple method that can be effectively applied to the design
of vehicle parts. 相似文献
208.
Julie Wallace Pavlos Kanaroglou 《Transportation Research Part D: Transport and Environment》2008,13(5):323-333
This study characterizes the dispersion of emissions of oxides of nitrogen and nitrogen dioxide from traffic sources in the Hamilton census metropolitan area. The Integrated Model of Urban Landuse and Transportation for Environmental Analysis software was used to estimate emissions of oxides of nitrogen from traffic sources. The Air Pollution Model, was used to simulate dispersion of the traffic emissions over the city. The models account for the two primary wind directions in this region – the prevailing southwest and a secondary northeast direction. The results show a prominent triangle of high pollution defined by major roads and highways along the periphery of the Hamilton Harbour, at peak-hour. With southwest winds, residential areas along the northern shoreline of the Harbour are affected, while the western sections of the city are affected by northeast winds. High concentrations are persistent in some areas, for both wind directions. The resulting dispersion surfaces characterize the spatial distribution of traffic emissions and thus provide a means of assessing population exposure over the Hamilton area. 相似文献
209.
基于用地分析的公交站场布局规划研究 总被引:1,自引:0,他引:1
城市规模的不断扩大和城市化进程的加快使得大城市的交通问题日益突出,大力发展公共交通,是解决密集型大都市交通问题的有效办法。文章介绍广州市公交站场布局方法,分析存在问题的原因,为此类设施用地规划提供参考。 相似文献
210.
Understanding of the activity-travel patterns of children is becoming increasingly important to various policy makers. Further,
there is also a growing recognition that intra-household interactions need to be explicitly accommodated in travel models
for realistic forecasts and policy evaluation. In the light of these issues, this paper contributes towards an overall understanding
of the school-travel behavior of children and the related interdependencies among the travel patterns of parents and children.
An econometric model is formulated to simultaneously determine the choice of mode and the escorting person for children’s
travel to and from school. The 2000 San Francisco Bay Area Travel Survey (BATS) data are used in the model estimation process.
Empirical results indicate that the characteristics of child like age, gender, and ethnicity, and employment and work flexibility
characteristics of the parents have strong impacts on the mode choice decisions. In addition, the impacts of some of these
attributes on the choice of mode to school are different from the corresponding impacts on the choice of mode from school. The distance between home and school is found to strongly and negatively impact the choice of walking to and from
school, with the impact being stronger for walking to school. Several land-use and built-environment variables were explored,
but were found not to be statistically significant predictors.
相似文献
Sivaramakrishnan Srinivasan (Corresponding author)Email: |