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231.
232.
本文对大客车热力特性进行了实验研究,实验内容包括车厢气密性,客车热力特性,空调系统制冷能力以及车围结构导热性等。本文还讨论了汽车稳太热载荷及车围结构导热的计算方法。 相似文献
233.
严云升 《电力机车与城轨车辆》2002,25(2):1-4
为了实现列车的互操作性,必须对列车总线上传送的数据规范化,而列车通信网络配置规范化是传送数据规范化的前提。文章分析了国内6种动车组网络配置的特点,对网络配置和传送数据规范化提出了建议,供今后网络设计者参考。 相似文献
234.
With the aim of identifying typical characteristics of travellers, traditional segmentation approaches were based on socio-demographic variables. However, the approaches could not reveal the factors motivating individual behaviour. This result led to an emerging interest in psychological research models that are adhered to the decision-making process. Among various related theories, the concept of loyalty was attractive because the major purpose of establishing a loyalty concept is to recognise a customer's pattern towards a given service. However, there were few efforts aimed at determining market segments based on a loyalty framework. In addition, there was no consensus achieved on theoretical loyalty typology due to different empirical findings in different market contexts. This study aims to be the first loyalty-based attempt to provide an operational method of segmenting bus service market. Seeking practical implementation, another focus of this study is to determine typical characteristics of the market segments. Analyses that included cluster techniques were conducted on questionnaire data collected from 333 respondents in Hidaka city, Japan. A cross-classification between relative attitude and service patronage was successfully established, dividing the market into four segments. Segments of loyalty and no-loyalty were observed to be dominant over the remaining market. In contrast, the spurious loyalty segment was small and insignificant. An expansion of the latent loyalty segment was also observed when moving from the intention phase to the actual behaviour phase. Notably, not only demographic factors but also social awareness variables including environmental concern and elderly support were observed to be significant in distinguishing customer segments from one another. 相似文献
235.
以某6120大客车为模型,通过建立客车车身的有限元模型,采用hyperworks软件,Radioss求解器求解。对客车在不同极限工况下的受力情况进行分析,为客车车身的后续改进提供指导。 相似文献
236.
系统分布电容大小是决定接地方式及接地装置参数的重要因素,本文通过计算发电机、变压器、母排 及电缆的分布电容经验公式,得到了无中压负载舰船的分布电容大小,为接地方式的确定提供技术依据. 相似文献
237.
238.
随着船舶自动化程度的不断提高,对船舶燃油舱的油位测量提出了更高的要求.针对船舶燃油舱的特点,设计了基于电容式油位传感器的油位测量系统,其原理是依靠测量传感器中介质的变化,获取油位的高度和油量,并实施了温度补偿和倾角补偿设计.实验结果表明,系统能够准确的以全量程线性化测量和显示. 相似文献
239.
ABSTRACT As maintenance and operation costs increase with usage over time, equipment is replaced when the value of new equipment is more attractive. Some methods have been developed to solve this problem. In the public transport sector, such problems are frequently analyzed by fleet managers and determined by bus age restriction regulations. We propose an Integer Programming model that integrates both budgetary and environmental constraints (CO2 emissions) which, as far as we know, have not previously been studied in conjunction. The study aims to determine the optimal replacement plan for a fleet of diesel buses of different size, age, maintenance costs and emissions rates, with new (less polluting) diesel buses over a time horizon of 50 years. The results indicate that it is possible to reduce emissions with a low annual budget using an optimal replacement policy. 相似文献
240.
When compared to large cities in developed countries, the shares of public transportation in most Chinese cities are low. Increasing the competitiveness of urban public transportation remains an urgent problem. A capable evaluation method for public transportation is required to assist the development of urban transit systems. This paper focuses on the bus system. Being devoid of standard criteria, it is difficult to determine the efficiency of a transit system or any bus line using a single evaluation index. This paper proposes a comparative analysis to evaluate bus lines so as to filter out candidates for further optimization. From the viewpoints of transit planning, operation and quality of service, this paper establishes 10 subordinate evaluation indices and then uses geographical information system tools, global positioning system data and smart card data to assist the index definition and calculation. Super-efficient data envelopment analysis (DEA) method is adopted for the proposed single factor and comprehensive evaluation models. Finally, the bus system in Shenzhen, China is used as a case study. The comparable significant results validate the capability of the proposed model. 相似文献