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81.
论金融危机下汽车行业发展形势 总被引:1,自引:0,他引:1
客观分析了全球金融危机对国际和国内汽车产业的影响以及有关汽车企业遭遇极大冲击的主要原因。同时,提出了以坚定的信心克服金融危机给汽车产业造成巨大困难的主张。还进一步论述了中国汽车产业坚持科学发展的重要性和必要性.阐明了平稳的增长速度才是正常的,平稳增长更有利于做强汽车业,平稳增长也有利于社会从容应对和适应汽车化的到来。总之,平稳增长才能保证中国汽车产业又快又好的健康发展。 相似文献
82.
Yang YANG Enjian YAO Hao YUE Yuhuan LIU 《Journal of Transportation Systems Engineering and Information Technology》2010,10(6):70-75
This paper focuses on support vector machine (SVM) based trip chain's activity type recognition. First, the time-series location information of person trip is processed to obtain the trip chain elements including moving processes and activities, and the activity options are extracted from the geographic information system (GIS) around the activity sites. Second, the activity features are drawn from spatio-temporal factors of trip chain to serve as the input feature vector of classifier. A SVM based one-to-one classifier is established and the method of one-to-one classifier voting is adopted to decide the most likely activity type from the activity options. Finally, the classifiers are trained with simulation data based on the Gaussian radial basis (RBF) kernel function and the multilayer perception (MLP) kernel function respectively, and then examined by cross validation. The result shows that in the one-to-one classifying scheme, the highest and lowest right recognition rate with RBF are 99% and 62%, and the corresponding results with MLP are 97% and 54%, respectively. 相似文献
83.
李张群 《现代城市轨道交通》2012,(5):60-63
对单线运营时期的城市轨道交通物资采购管理过程进行分析总结,在网络化运营阶段,结合基于供应链的物资采购管理理论,对传统的物资采购管理过程进行分析和优化,使不同的物资选择不同的采购模式和方式,实现库存量的最小化。 相似文献
84.
介绍作者设计的面向工业控制与管理一体化的 SASEC- PL C网络 ,涉及网络的拓卜结构内部协议和网络工作流程 ,最后简介内部网络的物理特性 相似文献
85.
86.
Competition and disruption in a dynamic urban supply chain 总被引:1,自引:0,他引:1
Terry L. Friesz Ilsoo Lee Cheng-Chang Lin 《Transportation Research Part B: Methodological》2011,45(8):1212-1231
Rapid changes and complexities in business environments have stressed the importance of interactions between partners and competitors, leading supply chains to become the most important element of contemporary business environments. There is a concomitant need for foresight in describing supply chain performance in all operating environments, including those involving punctuated disruptions. Furthermore, the urban metropolis is now widely recognized to be an environment which is especially vulnerable to supply chain disruptions and for which integrated supply chain decisions can produce very substantial net benefits. Accordingly, this paper presents a dynamic supply chain network model formulated as a differential variational inequality; the model is fashioned to allow consideration of supply chain disruption threats to producers, freight carriers, and retail enterprises. The DVI is solved using a fixed-point algorithm, and a simple numerical example, introduced to illustrate how the impacts of supply chain disruptions may be quantified, is presented. 相似文献
87.
Much Ado about Nothing? - An analysis of economic impacts and ecologic effects of the EU-emission trading scheme in the aviation industry 总被引:1,自引:0,他引:1
Jan Vespermann Andreas Wald 《Transportation Research Part A: Policy and Practice》2011,45(10):1066-1076
From 2012 on, all CO2 emissions from flights departing from or arriving at airports within the European Union have to be offset. We analyze the economic and ecological impacts that are caused by an inclusion of the aviation industry into the proposed emissions trading scheme (ETS). Building on the now fixed system design we employ a simulation model to estimate the impacts of the scheme. Our results indicate that financial impacts are highly dependant on external settings, such as allowance prices and demand growth. We show that the financial burden on the aviation industry will be rather modest in the first years after the introduction of the system and therefore induce only low competition distortions. Likewise, emission reductions within air transportation will be comparably low. While aviation will induce a decline of emissions in other sectors, significant absolute reductions within air transportation can only be reached by a more restrictive system design. 相似文献
88.
89.
研究一个简单供应链中的生产调度问题,目的是找到一个合理生产排序使得单位时间的成本最小,建立该问题的单目标非线性规划模型。运用模拟退火算法,结合邻域搜索进行求解,最后举例验证算法的有效性。 相似文献
90.
李亚云 《广州航海高等专科学校学报》2011,19(1):9-11,50
随着经济的发展,资源的紧缺,广东过去依靠外延扩张式的经济增长模式已经使其经济发展受到制约.随着中国经济和对外贸易的快速增长和广东目前所具有的港口资源的优势,发展海事经济对于推动广东经济转型,全面提升外向型经济竞争力具有重要战略意义. 相似文献