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131.
Nowadays, evaluating CO2 emissions efficiency and its marginal abatement cost in transportation sectors has been a hot topic. However, while evaluating the CO2 marginal abatement cost using data envelopment analysis approach, the weak disposability of CO2 may imply positive abatement cost, which undoubtedly violates our common sense. To obtain non-positive marginal abatement cost, CO2 emissions should be treated as an input. To reconcile this contradiction, this paper intends to propose a global, directional distance function model based on previous study to investigate the productivity, economic efficiency, CO2 emissions efficiency, and marginal abatement cost of the China’s regional transportation sectors during 2007–2012. The results show that: (1) the productivity, economic efficiency and CO2 emissions efficiency of different regions differ widely. More specifically, the coastal areas of south China perform better than the other areas in terms of productivity, economic efficiency, and CO2 emissions efficiency. (2) Generally, the economic efficiency is greater than CO2 emissions efficiency, which is relatively low in most areas. (3) A negative correlation is found between CO2 emissions efficiency and its marginal abatement cost. For a 1% increase in CO2 emissions efficiency, the CO2 marginal abatement cost declines by 102 Yuan (in 2004 constant price). The results imply that improving CO2 emissions efficiency plays an important role in marginal abatement cost reduction, and it also provides us a new approach to reduce abatement cost besides the technical progress.  相似文献   
132.
机场运营效率评价及影响因素分析对科学反映中国主要民用机场运营效率现状,实现中国民航业可持续发展,提高中国机场国际竞争力具有重要意义.本研究首先利用双重导向型DEA模型测算2006-2010年中国27个主要民用机场的运营效率,然后从宏观环境、行业与区域竞争及机场特征三个方面探索机场运营效率的影响因素.研究结果表明,2006-2010年中国主要民用机场的运营效率基本维持在较高水平;各机场的运营效率自2008年始均有不同程度的下降,且机场间运营效率的差异呈现逐年增大的趋势;腹地经济、机场规模、机场级别和一市多场等因素促进了机场运营效率的提升;区域竞争和行业竞争则不利于机场运营效率的提升.  相似文献   
133.
王晓华  于明明  王朝辉 《城市道桥与防洪》2013,(1):118-122,125,12,13
绿色生态型城市道路横断面是基于宜居城市生活的追求和能源危机的必然趋势,然而国内研究只是针对城市道路横断面组成要素的布置,在评价体系方面尚是一片空白。因此,基于城市道路横断面体现绿色、生态的影响因素,针对交通安全、降噪、空间伸缩、道路绿化、视觉美感、公众满意度、土地利用、建设投资等方面,提出八大指标评价标准;建立基于模糊重构DEA的绿色生态型城市道路横断面的优化模型;并以天津滨海新区为例,对生态城、中心渔港和西区的典型横断面布置方案进行了优化。结果表明:天津滨海新区西区横断面最优,建议生态城横断面机非分隔带加大至4 m。该方法科学可靠,实用性强,可为城市道路横断面提供有效决策方案。  相似文献   
134.
系统分析了纵断面设计的关键因素,并且结合某工程实例,为多约束条件的复杂纵断面设计提供了思路和方法;通过研究评价指标与评价方法的对应关系,提出了基于DEA方法的纵断面方案定量评价方法,解决了以往定性选择纵断面方案时易产生的主观性、片面性的问题.  相似文献   
135.
Despite the growing amount of research on container-port efficiency and benchmarking, the literature on the subject is yet to provide stable and consistent results across researchers and in relation to dynamic operating and market conditions. In this paper, we formulate a number of operational hypotheses to test the sensitivity of benchmarking results to port market and operating conditions namely production scale, cargo mix, transhipment ratio, operating configurations, and working procedures. A series of data envelopment analysis (DEA) models are used to measure the operational efficiency of 420 container terminal decision-making units from 2004 till 2010. The results show that variations in operating conditions highly impact terminal efficiency and that future work on container-port performance and benchmarking should take into account the structure and mechanisms underpinning the operations of container ports and terminals.  相似文献   
136.
Conventional data envelopment analysis (DEA) models consider a system as a single-process ‘black box’. There are, however, DEA approaches that consider a system as composed of distinct processes or stages, each one with its own inputs and outputs and with intermediate flows among the stages. In this paper, a network DEA approach to airline efficiency assessment is presented. One conclusion of the study is that the network DEA approach has more discriminative power than the single-process DEA approach and that the computed targets, efficiency scores and rankings are more valid. This is because network DEA allows for a more fine-grained analysis that leads to a more realistic estimation of the overall system production possibility set than the one assumed by conventional DEA. In other words, compared with network DEA the conventional, single-process DEA represents an aggregated analysis that merges all system processes with their inputs and outputs and ignores their internal flows. The main drawbacks are the need for more detailed data (i.e. at the process level) and the greater complexity of the resulting models, especially if there are inputs or outputs that are shared among the processes.  相似文献   
137.
Abstract

This paper estimates comprehensive operational performance measures for transport services. A network efficiency approach is used to analyze the production efficiency, service efficiency, and operational efficiency in a unified framework to reflect the transportation service characteristics of airline operations. We show how a modified version of the network data envelopment analysis model can be utilized for evaluating the performance of air route operations. This study considers 15 air routes operated by a domestic airline in Taiwan to highlight the value of the approach. The results of the analysis show the inputs and consumed outputs leading to production inefficiency and service inefficiency respectively as well as the magnitudes of excesses and shortfalls.  相似文献   
138.
张倩  陈桂明  颜宁  苏保忠 《舰船电子工程》2012,32(11):64-67,106
针对维修信息资源特点,以装备维修系统投入、产出为双目标,兼顾决策者偏好,引入环境背景值及针对多阶段过程的时间窗,建立装备维修信息资源优化配置DEA模型,并采用基准化思想评价资源配置效率。算例分析结果符合实际,最优结果和效率评价分析为决策者提供决策支持,利于提高装备维修保障效用,充分发挥装备维修资源作用。  相似文献   
139.
140.
采用三阶段DEA模型测度出中国高新技术产业17个行业的平均创新效率,并将其分解为配置效率和研发效率。在此基础上得出我国高技术产业的创新效率的特点:第一,平均创新效率较低主要是由于低配置效率所导致;第二,同时发现我国高新技术产业研发效率主要受制于低规模效率。第三,高技术产业当前推动研发效率提升的同时却是以配置效率的下降为代价。因此,应注重发挥市场对于资源的配置效率,做到研发效率与配置效率的权衡,从而确保效率最大化。  相似文献   
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