技术经济视角下国家铁路生产效率测定研究

研究目的:国家铁路作为铁路系统主要组成部分,对国民经济发展起着重要作用,通过技术创新提高国家铁路的生产效率是其发展的必然之路。文章从国家铁路技术经济因素出发,采用基于熵权的模糊物元方法测定四个分类的技术因素值,然后将其作为投入变量采用DEA方法测定近12年的国铁生产效率。研究结论:(1)国家铁路系统的技术经济因素整体呈现逐年改善的趋势;(2)规模无效率是导致综合技术效率低下的主要原因;(3)从长远看,国家铁路系统进行技术创新,提高技术经济因素才是其实现和谐、可持续发展的必然之路。     

基于DEA的城市轨道交通规划线网综合评价研究

研究目的:在分析城市轨道交通规划线网评价指标体系及评价方法现状的基础上,优化评价指标体系,运用DEA方法建立城市轨道交通规划线网评价的优化模型,给出求解方法,并通过算例说明其可行性,为确定城市轨道交通规划线网方案提供决策依据。研究结论:城市轨道交通规划线网评价是轨道交通规划的关键环节,对于确定技术上先进、经济上合理、实施上可行的最优或满意的城市轨道交通规划线网方案具有极其重要的作用和意义。通过研究表明:采用DEA方法对城市轨道交通规划线网进行综合评价具有操作简单,可综合考虑各输入输出指标,以及能够确定最优方案的特点,具有一定的实用价值。     

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城市综合交通枢纽评价能否客观有效,将对城市综合交通系统的规划和发展产生重大影响。因此,本文重新整合数据包络分析法（DEA）,在传统CCR模型基础上,补充决策单元（DMU）排序方法,使其不但能够指出各决策单元是否有效及无效的原因和程度,同时得到各决策单元的优先排序。并将该方法应用到城市综合交通枢纽评价领域,不仅得到各枢纽或同一枢纽的不同规划方案的排序值,而且找到DEA无效枢纽或方案所存在的症结和改进的方向。最后,通过实例验证了该方法的可行性。     

DEA模型在船闸运行效率评价中的应用

根据船闸运行的特点,建立了评价船闸运行相对有效性的DEA（C2R）模型,选取了决策单元,构建了投入产出指标体系,并结合江苏典型船闸进行了具体运用,得到泗阳船闸等4座船闸运行为相对有效。最后计算了各船闸输入冗余率和输出亏空率,为江苏船闸管理部门决策提供参考。     

企业物流作业成本控制的DEA模型

为解决作业成本（ABC）法在物流成本控制方面可操作性差的问题，建立了物流作业成本控制数据包络分析（DEA）模型．该模型的运行机理是用DEA方法将物流作业作为决策单元评价输入输出要素的运作效率．根据评价结果，保留高效率作业，并对低效率作业提供改进目标和方向．物流作业成本控制DEA模型的关键步骤分别是建立企业物流作业库、分解物流作业和确定物流作业决策单元的效率．     

Efficiency in Nigerian ports: handling imprecise data with a two-stage fuzzy approach

This article is focused on assessing the efficiency of six major Nigerian ports from 2007 to 2013 by applying a two-stage fuzzy-based methodology adequate to handle imprecise data. More precisely, fuzzy data envelopment analysis models for traditional assumptions with respect to scale returns are employed to assess the productivity of Nigerian ports over the course of time. In the second stage, fuzzy regressions based on different rule-based systems are used to predict the relationship of a set of contextual variables on port efficiency. These contextual variables are related to different aspects of port service level, berth utilization, accessibility, cargo type, and operator type. The results reveal the impact of operator and cargo type on efficiency levels. Policy implications for Nigerian ports are derived.     

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以建设节约型交通为发展目标,以科学性、系统性以及可操作性为原则,在充分考虑投资者、管理者与使用者意见的基础上将车辆运行速度、行车延误、通行能力、交通安全、交通噪声污染,以及车辆尾气排放相结合构成ETC交通效益评价指标体系.通过定性与定量相结合的方法,给出各评价指标的量化值.运用数据包络分析法(DEA)对不同交通流状态下ETC建设项目的交通效益进行超效率分析.最后通过实例验证不仅给出了不同交通量条件下ETC建设项目的交通效益超效率量化值,而且将不同交通量所对应的效益值相对比,从而找出导致效益较低的根本原因,并有针对性地采取改进措施.     

苏州市居民幸福指数调查统计与效率分析

随着GDP的不断增长，以及居民收入的不断提高，居民的生活水平也随之不断改善。苏州地处长江三角洲，经济发展水平居全国前列，高GDP。增长情况下，分析居民的幸福指数意义重大。本文以苏州市为例，首先构建了幸福指数的评价指标体系，利用问卷调查与统计数据定量分析苏州市居民生活幸福指数。进而利用非径向DEA模型对居民生活中的物质投入与精神产出进行效率评价，最后针对计算结果作了原因分析。     

Pole location control design of an active suspension system with uncertain parameters

This paper addresses the problem of robust control design for an active suspension quarter-car model by means of state feedback gains. Specifically, the design of controllers that assure robust pole location of the closed-loop system inside a circular region on the left-hand side of complex plane is investigated. Three sufficient conditions for the existence of a robust stabilizing state feedback gain are presented as linear matrix inequalities: (i) the quadratic stability based gain; (ii) a recently published condition that uses an augmented space and has been here modified to cope with the pole location specification; (iii) a condition that uses an extended number of equations and yields a parameter-dependent state feedback gain. Unlike other parameter-dependent strategies, neither extensive gridding nor approximations are needed. In the suspension model, the sprung mass, the damper coefficient and the spring constant are considered as uncertain parameters belonging to a known interval (polytope type uncertainty). It is shown that the parameter-dependent gain proposed allows one to impose the closed-loop system pole locations that in some situations cannot be obtained with constant feedback gains.     

Robustness of autonomous underwater vehicle control in variable working conditions

The performance of the control systems of autonomous underwater vehicles (AUVs) in the presence of parameter variations was studied. With an AUV working at different operating speeds and in different ocean environments, the physical parameters such as speed, hydrodynamic coefficients, or inertias may be perturbed from their nominal values. The vehicle control systems can be modeled as systems with parameter uncertainty. An existing robust control method, which uses the robustness properties of polynomials, was used for this system to calculate the permissible ranges of variation in the parameters. The method was applied to the Naval Postgraduate School AUV II and the results were verified by simulating the motion control of the vehicle under the influence of parameter perturbations.