铁路敞车车门检修中存在的问题及检修工艺改进

随着我国经济的快速发展,国家越来越重视铁路敞车车门检修问题以及工艺改进。为了进一步革新铁路敞车车门检修工艺,应当根据实际情况了解铁路敞车的车体组成部分,充分利用耐腐蚀性、密封性以及安全性等特性,对铁路敞车门锁安全进行综合分析和考量。论文主要针对铁路敞车车门检修中存在的问题及检修工艺进行简要分析,并提出一些合理化建议。     

关于新一轮国土规划性质及其理论体系建设的思考

从新时期国土规划的性质及地位出发,运用多学科综合研究国土规划的理论体系建设问题,在此基础上运用层次分析法探讨国土规划的编制思路,最后提出未来国土规划应着力解决的重点。     

China Railway Informalization System Research Based on Reengineering

Consulting concepts of business process reengineering of modem enterprises and according to networked industry characteristics of railway, this article analyzes restructuring experience modes of foreign railway, probes into the trend of China railway restructure, and makes it clear that railway should set up modem enterprise systems by focusing on transport as major trade. As a result, the railway informalization system shall be guided by marketing, aiming at improving the operation efficiency and management benefits, having priority in passenger and goods marketing system development. Central control and safeguarding systems should be emphasized in construction and railway business management systems shall be broueht about.     

Embodied and Disembodied Technical Change in Fisheries: An Analysis of the Sète Trawl Fishery, 1985–1999

Overfishing and excess capacity in mostfisheries around the world have generated considerableand increasing concern about their biological and economic performance ramifications. Theseproblems, in part, stem from substantialinvestment in technical improvements to boats andequipment in fishing fleets, which exacerbatesexcess fishing capacity and low returns tofishing effort and investment, given regulatoryand biological constraints. However, little attempt hasbeen made to quantify the extent or effects oftechnical change in fisheries. In this paper, we usedetailed data on innovation patterns for 19vessels in the Sète trawl fleet of southernFrance to evaluate the contributions oftechnical change to catch rates. We find thatembodied technical change enhanced productivity by approximately one percent per year between 1985 and 1999, but that external (disembodied) events counteractedthis trend, causing a net output decline ofabout three percent per year.     

武陵山片区旅游节点交通畅达性研究

区域旅游节点的交通畅达性对区域经济发展具有强劲的推动作用,区域旅游节点的交通畅达性优劣取决于内部的连通性和外部的可达性。文章基于因子分析法分别就高等级公路、高速公路、普铁、高铁(动车)、民航航线等因素对武陵山片区内各旅游节点的交通畅达性的影响进行了评价分析,对各旅游节点的畅达性进行了排名;并选取2010、2014、2018年等3个时间节点数据导入GIS生成3个片区旅游交通图。研究发现:①重庆、武汉、长沙、贵阳四大中心城市的交通连线支撑起武陵山片区的交通网络,片区旅游节点之间的畅达性逐步提升;②处于武陵山片区外围重庆、武汉、长沙、贵阳四大中心城市交通大廊道上的旅游节点之间畅达性处于片区前列;③同一省市或同一传统旅游线路的旅游节点连通性较好,分属不同省市的旅游节点之间连通性普遍较差;④历史上,山高谷深、交通闭塞,各地市自然旅游资源丰富多样,文化旅游浓郁独特,近年来,武陵山片区旅游发展与交通建设相互推拉,呈现良性发展。     

2002～2005年间我国不同地区高校科技创新效率比较研究

利用SPSS13.0对2002～2005年间我国各省、市、自治区高校科技创新活动进行了聚类分析,并采用DEA的CCR模型对这4年中我国各省、市、自治区高校科技创新过程中经费支出,以及人员投入的效率问题进行了比较研究,结果发现有24个地区DEA有效,6个地区非DEA有效。最后给出了非DEA有效地区的改进方向。     

技术型跨国企业实施知识产权战略的动因探析

知识产权战略作为技术型跨国企业的重要竞争战略,企业在实施该战略时有其内在和外在的动因。分析知识产权战略与企业战略及其他职能战略的内在联系,揭示技术型跨国企业实施知识产权战略的内在动因;分析国际经济和贸易环境的变化、技术进步带来的影响,揭示技术型跨国企业实施知识产权战略的外在动因。     

A Stochastic Frontier Production Function with Flexible Risk Properties

This paper considers a stochastic frontier production function which has additive, heteroscedastic error structure. The model allows for negative or positive marginal production risks of inputs, as originally proposed by Just and Pope (1978). The technical efficiencies of individual firms in the sample are a function of the levels of the input variables in the stochastic frontier, in addition to the technical inefficiency effects. These are two features of the model which are not exhibited by the commonly used stochastic frontiers with multiplicative error structures.An empirical application is presented using cross-sectional data on Ethiopian peasant farmers. The null hypothesis of no technical inefficiencies of production among these farmers is accepted. Further, the flexible risk models do not fit the data on peasant farmers as well as the traditional stochastic frontier model with multiplicative error structure.     

技术变革与经济学研究的理论创新

以大机器为代表的工具技术变革和由此而诞生的现代工业经济体系,以及建立在工业及后工业时代基础之上的传统经济学理论,已经无法适应建立在数字技术、基因技术变革基础之上的新经济发展的实践。在传统经济学理论基础之上,构筑与新经济时代相适应的经济学理论体系,实现经济学研究的理论创新,是当代经济学人的重要历史使命。     

基于不确定运输时间的军械紧急调运模型研究

针对运输时间不确定的军械紧急调运问题，将运输时间处理为模糊随机变量，建立在任务时间限制期下的最大可能性路径选择模型以确定调运路径。而后，引入超期风险概念，建立以超期风险最小为首要优化目标的军械紧急调运多层觇划模型，实现了对调运方案的优选。最后，给出一个具体军械调运实例来验证模型的适用性。