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131.
基于DEA的物流产业发展能力评估模型   总被引:1,自引:0,他引:1  
张兴远 《中国水运》2007,5(10):131-132
以数据包络分析的方法建立物流产业发展能力的评估模型,以此为物流产业发展的优化与调整、物流产业的投资规模和投资政策、产业发展政策方面提供科学的依据。  相似文献   
132.
针对变流器数字控制系统的DSP,MCU和FPGA芯片需要快速、可靠地完成一定数据量通信的要求,基于FPGA的IP软核实现双口RAM方法,研究适用于MCU,DSP和FPGA芯片间的数据通信技术。首先利用Altera公司提供的FPGA开发环境Quartus中的MegaWizard进行配置,实现1个双口RAM模块;基于该模块,依次设计单向三口RAM模块、双向三口RAM模块以及双向三口RAM模块与MCU和DSP芯片的接口部分,并将带有与MCU和DSP芯片接口的双向三口RAM模块封装成1个用户可以直接使用的顶层模块。对该顶层模块进行编译的结果表明:该技术可以可靠、经济和方便地实现变流器数字控制系统中MCU,DSP和FPGA芯片间的数据通信。  相似文献   
133.
本文介绍由MCS 8031单片机控制的汽车起动电机出厂参数测试台的A/D采样板的设计与数据处理系统的软件设计。本设计选择双积分型A/D转换芯片,并采用光电隔离装置,有效地降低了电源噪声和电机干扰,大大提高了转换精度。本设计还采用了硬件软化技术,用软件实现数据的锁存、缓冲、地址切换等功能,既节省了硬件开支,减少印刷电路板的面积,又使接口电路通用灵活。  相似文献   
134.
This paper studies the problem of evaluating the relative efficiency of a set of specialized and interdependent decision-making subunits that make up a large decision-making unit (DMU). The paper develops a data envelopment analysis (DEA) approach for measuring the efficiency of decision processes which can be divided into two stages. In these processes the first stage uses its own inputs to generate outputs which a part of these outputs become the inputs to the second stage. Moreover, DMUs use shared input sources in both operation stages. This paper provides a set of additive models which measure the performance of two-stage network DEA processes with shared inputs. Numerical examples show the applicability of the approach.  相似文献   
135.
This study addresses the issue of eco-design for transportation in sustainable supply chain management (SSCM). Data envelopment analysis (DEA) is adopted and extended to construct a model for this application. This proposed model, together with the tractable algorithm developed in this research, can provide stakeholders with a Pareto Optimal transportation strategy. This derived transportation strategy can help stakeholders realize certain transportation goals with less resource consumption and pollution emission. The discussion presented leads to a heuristic Joint Transportation Policy and concludes with two useful suggestions for putting the strategy into practice. The proposed model was used in an empirical study of design sustainable transportation mechanism for one air-condition manufacturer in China to transport its products as well, the analysis further demonstrating the theoretical and practical value of this research.  相似文献   
136.
应答器报文是实现CTCS-2级列控系统功能的关键数据。介绍了一种基于数据可视化方法分析验证应答器报文的软件——BTViewer的设计和实现,该软件为应答器报文的设计分析、现场维护提供了全新的手段和工具。  相似文献   
137.
CUBE操作在数据仓库/联机分析处理中是一个关键性的操作,它需要计算一个属性列表上的所有可能的组合,并等价于标准sQL中一组group by子句.作者分析了CUBE操作的几种实现方法,并扩展了一种以group by子司共享排序为基础实现CUBE操作的优化算法,在应用中有较好的效果.  相似文献   
138.
铁路货票信息的数据挖掘   总被引:1,自引:0,他引:1  
从三个方面对货票数据进行挖掘。即:运用集合理论构造关系数据库特征关联模型,描述了特征规则知识的表达:rule(E,T,Cp),给出rule(E,T,Cp)的发现算法和算法的应用举例,实例表明铁路多年来把标重作为计算整车费率唯一因素的办法应作适当调整;运用聚类方法对货票数据进行聚类,描述了聚类的步骤,对某公司2000年度的运距和收入进行聚类,分析聚类结果对铁路生产经营、市场营销的启示;运用ARIMA模型对货票数据进行季节性知识挖掘,描述挖掘的过程,用1992年~2001年的历史数据预报2002年货运量。  相似文献   
139.
Advances in Information and Communication Technologies (ICT) allow the transportation community to foresee dramatic improvements for the incoming years in terms of a more efficient, environmental friendly and safe traffic management. In that context, new ITS paradigms like Cooperative Systems (C-ITS) enable an efficient traffic state estimation and traffic control. C-ITS refers to three levels of cooperation between vehicles and infrastructure: (i) equipped vehicles with Advanced Driver Assistance Systems (ADAS) adjusting their motion to surrounding traffic conditions; (ii) information exchange with the infrastructure; (iii) vehicle-to-vehicle communication. Therefore, C-ITS makes it possible to go a step further in providing real time information and tailored control strategies to specific drivers. As a response to an expected increasing penetration rate of these systems, traffic managers and researchers have to come up with new methodologies that override the classic methods of traffic modeling and control. In this paper, we discuss some potentialities of C-ITS for traffic management with the methodological issues following the expansion of such systems. Cooperative traffic models are introduced into an open-source traffic simulator. The resulting simulation framework is robust and able to assess potential benefits of cooperative traffic control strategies in different traffic configurations.  相似文献   
140.
This paper proposed a novel feature selection method LUIFS (latent utility of irrelevant feature selection) that not only selects the relevant features, but also targets at discovering the latent useful irrelevant attributes by measuring their supportive importance to other attributes. The method minimizes the information lost and simultaneously maximizes the final classification accuracy. The classification error rates of the LUIFS method on 16 real-life datasets from UCI machine learning repository were evaluated using the ID3, Nave-Bayes, and IB (instance-based classifier) learning algorithms, respectively; and compared with those of the same algorithms with no feature selection (NoFS), feature subset selection (FSS), and correlation-based feature selection (CFS). The empirical results demonstrate that the LUIFS can improve the performance of learning algorithms by taking the latent relevance for irrelevant attributes into consideration, and hence including those potentially important attributes into the optimal feature subset for classification.  相似文献   
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