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161.
采用节点拆分的方式构建了既有繁忙干线货运产品网络,在此基础上按运输需求的特征对其分类并借鉴服务网络设计的思想,设计了既有繁忙干线铁路货运产品布局优化模型,采用免疫克隆变邻域搜索算法对模型进行求解,最后采用算例对模型和算法进行验证分析,测试结果表明模型和算法具有较好的适用性. 相似文献
162.
奥迪100轿车后螺旋弹簧的可靠性设计 总被引:6,自引:0,他引:6
本文介绍了奥迪100桥车后螺旋弹簧的可靠性设计方法。在基本随机变量的概率特性已知的情况下,使用二阶矩技术对弹簧的可靠性进行设计,所编制的计算机程序可以迅速准确地得到弹簧的可靠性设计参数。 相似文献
163.
通过在虚拟三维环境中怎样对汽车模型进行灯光设置的研究,提出车身金属材质的具体设置方法,以及对虚拟场景中灯光的设置,以达到显示其形状、材质、气势等效果,追求虚拟三维汽车模型的艺术效果。 相似文献
164.
A field experiment was conducted to investigate the effects of economic disincentives on private car use. Eighty two-adult households who were owners of at least one car were randomly assigned to three experimental groups and one control group. Both experimental and control groups logged their car trips during one week before, one week during, and one week after treatment. The treatment consisted of charging two of the experimental groups approximately 100% of normal cost per kilometer of driving during 2 weeks, and charging the third experimental group this amount per kilometer of driving during 4 weeks. With the purpose of investigating whether deliberate planning increases the effect of economic disincentives, the households in one of the former and in the latter group were asked to fill out a prospective car log for the following week. The control group was not charged or requested to fill out a prospective car log but was in other respects treated in the same way. Analyses of the car logs and odometer readings during and at the end of treatment showed a weak reduction of car use due to the economic disincentives that however were almost completely dependent on planning. 相似文献
165.
本文首先简要地分析了声激励减阻机理,然后,针对类似桑塔纳车身的模型采用了声激励的方法进行了减低空气阻力的研究,得出了声激励参数,方式和减阻效果的关系,并且对此进行了一定的分析,表明利用声激励方法可以进一步降低此类车身的空气阻力。 相似文献
166.
随着汽车产业的蓬勃发展,汽车造型设计越来越注重民族元素的应用,逐渐步入本土品牌化.在国产汽车突飞猛进的今天,将中国元素融入到国产汽车设计之中,具有非常重要的作用和意义.如何将优秀的中国传统文化元素完美应用到汽车造型设计中,大量的优秀汽车设计师进行了成功的探索和尝试,并取得了可喜的成绩.在东方大国文化自信的背景下,打造出... 相似文献
167.
168.
There are factors that impact car usage in urban areas, such as density, diversity and design, but there have been few studies that examine the relationship between street network factors and car usage at the city level (macro level). This paper focuses on this relationship by introducing urban street network variables, such as blocks per area, nodes per block and length of roads and motorways, as independent variables and the percentage of daily trips by private motorized modes as the dependent variable. The street network in this study includes interconnecting lines and points that present streets, roads, motorways, intersections and blocks. The strength of the relationship in this study is found using multiple linear regression. The findings of this research indicate that an increase in car usage is correlated with an increasing number of blocks per area, number of nodes per block and length of motorways. In addition, because the urban street network is the result of macro-scale planning decisions, considering this relationship can lead to better planning decisions. 相似文献
169.
170.