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331.
通过对新造城市轨道车辆车体表面处理工艺的研究,结合生产纲领计算表面处理台位需求,确定新筑新材料基地表面处理车间平面布置、设备配置方案,研究成果可为国内其他类似项目设计提供借鉴。  相似文献   
332.
通过城市道路交通事故的成因分析,对城市道路交通主动安全控制系统的构建进行了研究。提出了系统的结构框架、物理构造、工作流程和系统功能。运用先进的信息采集技术、网络信息传输技术、智能化信息处理技术和现代控制技术改变现有被动的交通安全管理模式,实现了交通事故事前的主动防御功能,可有效避免交通事故的发生,提高城市道路交通安全管理水平。  相似文献   
333.
随着秦皇岛市城市发展和城市结构调整,城区内部铁路的运量正逐年下降,部分铁路货运专用线即将废弃。而秦皇岛市作为著名的滨海旅游城市,近年来旅游人口快速增长,再加上不断增加的本地居民出行需求,其交通拥堵现象越来越严重。参照其他城市利用既有铁路资源发展轨道交通的经验,结合秦皇岛市铁路现状及客流需求分析,提出了利用既有铁路发展城市轨道交通的方案,以缓解交通拥堵,提升城市交通品质。  相似文献   
334.
This study analyzes the performances of updating techniques in transferability of mode choice models in developing countries. A model specification, estimated in Ho Chi Minh City, was transferred to Phnom Penh. Naïve transfer and four updating methods associated with small sized samples were used in the transfer process and were evaluated based on statistical perspective and predictive ability. The study also illustrates the problems faced in model transferability development, due to the lack of available and suitable data in Phnom Penh. This lack is strongly related to different methods and structures applied in collecting the data. Simplified approaches to the difficulties are proposed in the study. The results show that updating ASCs, updating both ASCs and scale parameter, and use of combined transfer estimators all produce significant improvement, both statistically and in predictability, in updating the model. The last two methods have proven to be superior to the first method, owing to the inclusion of transfer bias considerations in the estimations. However, small data samples should not have large transfer bias when using combined transfer estimators. It is also concluded that naïvely transferring a model is not recommended, and Bayesian updating should be avoided when transfer bias exists. Copyright © 2010 John Wiley & Sons, Ltd.  相似文献   
335.
王琛 《中南公路工程》2011,(2):83-86,140
从交通量、周边路网分析、用地性质、交通疏解等影响因素出发,理论上论述了城市道路立交的方案选择,同时结合长沙市湘府路湘江大桥工程两岸接线立交的工程实际案例来论述城市道路立体交叉的设计与优化。  相似文献   
336.
洪成佳 《中国水运》2006,6(9):200-201
采用AHP层次分析法,利用Excel对反映湖北省12个主要城市的城市竞争力的19项指标进行数据处理与分析,得出其竞争力的综合分值及排名,并对湖北省各地区城市作综合评价。  相似文献   
337.
The street-network efficiency of tens of British cities in relation to transport fuel consumption and CO2 emissions are analyzed. The results show a strong linear positive correlation between length entropy and average street length, and a negative correlation between entropy and street density. Also, the results suggest that in a large city the street network is used more efficiently than in a small city, as indicated by the sublinear relations between city size (population) and the number of streets, total length of streets, and the area covered by the street network. The sublinear relation means that these parameters grow more slowly than the city size. By contrast, because a larger fraction of the street network is used at close to full capacity during considerable part of the time in a large city than a small one, the fuel consumption and the CO2 emissions show a linear relation with city size and superlinear relation with total street length. The superlinear relation means that the CO2 emissions increase faster than the total street length, a measure of the network size. Thus, large cities may be less energy efficient and environmentally friendly than small cities. In every city the street network needs to interconnect all the buildings, which requires a certain minimum size. In a small city, however, the network is used to a low capacity most of the time so that its relations to fuel consumption and the CO2 emissions are more favorable than those in a large city.  相似文献   
338.
ABSTRACT

This article examines the spatial transferability of mode choice models in developing countries. An evaluation of the updating procedure and sample size are also included in the study. Because of the insufficiency of model coefficients in explaining differences in unmeasured modal attributes, naïvely transferring a model is not recommended. An understanding of the transport characteristics in both the estimation context and the application context is required, in order to justify whether a variable is transferable or not. Four updating procedures – updating alternative specific constants (ASCs), updating ASCs and scale parameter, the combined transfer estimator and Bayesian updating associated with three sets of small sample sizes – are applied to improve transferability. In general, the first three approaches produce significant improvements. It is also proposed that a minimum small sample size of 400 observations is necessary for updating purposes.  相似文献   
339.
董俊红 《城市道桥与防洪》2013,(4):156-159,169,8
大型市政工程施工期间,改变了城市道路原有的交通和行车环境,易导致交通拥堵、通行能力下降、安全事故等发生,项目建设前应进行施工期间的交通组织研究分析并优选方案,才能有效地保障施工期间城市交通的良性运转。结合实际案例,着重探讨交通组织及管理措施,可为此类工程建设提供参考。  相似文献   
340.
该文通过对桂林交通现状的描述,表明现在城市交通拥堵已日趋严重,要想很好地解决城市交通拥堵问题,目前已是关键时期。解决城市交通问题应建立科学的意识形态,只有在科学意识指引下才能做出科学的决策。公交优先已成为老生常谈,而如何将这一思想变成政策并付诸实践,这才是解决问题的关键。接着,根据历年的工作体会并结合大量城市交通现状调查的成果,提出若干条保证公交优先的基本措施,可供决策层在解决城市交通拥堵问题时作参考。  相似文献   
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