首页 | 本学科首页   官方微博 | 高级检索  
文章检索
  按 检索   检索词:      
出版年份:   被引次数:   他引次数: 提示:输入*表示无穷大
  收费全文   1479篇
  免费   30篇
  国内免费   4篇
财政金融   20篇
工业经济   33篇
计划管理   614篇
经济学   106篇
综合类   43篇
运输经济   451篇
旅游经济   36篇
贸易经济   106篇
农业经济   19篇
经济概况   85篇
  2024年   5篇
  2023年   14篇
  2022年   21篇
  2021年   32篇
  2020年   20篇
  2019年   29篇
  2018年   31篇
  2017年   42篇
  2016年   41篇
  2015年   57篇
  2014年   144篇
  2013年   114篇
  2012年   112篇
  2011年   150篇
  2010年   106篇
  2009年   88篇
  2008年   114篇
  2007年   81篇
  2006年   74篇
  2005年   62篇
  2004年   56篇
  2003年   47篇
  2002年   11篇
  2001年   5篇
  2000年   14篇
  1999年   6篇
  1998年   10篇
  1997年   5篇
  1996年   5篇
  1995年   3篇
  1992年   1篇
  1989年   1篇
  1985年   2篇
  1984年   3篇
  1982年   6篇
  1979年   1篇
排序方式: 共有1513条查询结果,搜索用时 0 毫秒
141.
经济系统中各个产业之间存在着关联,而一国各个产业之间的关联,部分外溢为国内产业与国外产业之间的关联,即存在着产业关联外溢的问题。本文基于中国交通设备制造业的数据,分析2002-2010年该产业在投入产出表中的相关变化,测算该产业及其产业关联外溢对中国经济增长的效应;并进一步考察了产业关联外溢与国内增加值之间的动态联系。最后,探讨了产业关联外溢问题对产业体系内生形成的启示。  相似文献   
142.
基于2003—2018年19个大城市数据,设置空间地理权重矩阵计算Moran′s I指数和Geary′s C指数检验城市创新产出的空间自相关,借助stata软件构建并选择时空双固定效应的空间面板杜宾模型.实证性研究发现航空运输能够压缩城市时空距离,加快人才流动中所产生的知识空间溢出,促进城市创新能力;进一步研究表明,发展航空运输与现代通信技术对于城市创新能力的影响呈互补关系;航空运输通过增强知识精英与研发资金、教育活动投入等创新要素之间的相互作用,从而促进城市的创新能力,并且也对周边城市的创新能力起到积极作用.  相似文献   
143.
Instruments used to regulate the consumption of oil in the transport sector include fuel taxes, biofuel requirements, and fuel‐efficiency standards. However, the effects that these have on oil consumption and price vary. If market power is present in the oil market, the directions of change in consumption and price might contrast with those in a competitive market. As a result, the market structure affects not only the effectiveness of the policy instruments used to reduce oil consumption, but also the terms of trade and carbon leakage. In particular, reduced oil consumption, as a result of increased fuel‐efficiency standards, will unambiguously increase the price of oil under a monopoly.  相似文献   
144.
This paper analyses slow steaming sustainability initiatives and generalizes the traditional discrete cost-based decision support model into novel continuous utility-based models. Two models based on logarithmic and linear utility functions are developed for risk-averse and risk-neutral decision makers respectively. The models, considering fuel consumption, carbon emission, and on time delivery, are applied to a Trans-pacific trade service route. A sensitivity analysis is conducted on parameters of sailing distance, expected transit time, quantity, and emission policies. The model contributes to ship liners on the optimal speed decisions in continuous utility-based slow steaming operations.  相似文献   
145.
集装箱集疏运体系结构不合理、公路比例偏高已成为制约上海国际航运中心可持续发展的因素,无论是从环境保护、节能减排的客观要求出发,还是从上海国际航运中心可持续发展的主观能动性出发,都要求集疏运体系由公路向水路与铁路转移,优化集疏运体系结构,实现上海国际航运中心的可持续发展。  相似文献   
146.
The effectiveness of imperfect pollution control instruments is examined for a diffuse source, multi-contaminant problem in which the transport coefficients for sediment-bound residuals are endogenous. Similar evaluations fix the percentage of sediment deposited and optimize either for a single firm managing the whole watershed or on a firm by firm basis. This study shows that ignoring the dependence of the transport coefficients on intervening land uses creates a positive externality. The filtering potential of activities conducted by firms close to the receptor permits firms further away to undertake more profitable but erosive practices. Optimizing management choices, and consequently endogenizing the transport coefficients, for all firms simultaneously removes the externality. An empirical application combines hydrological simulation models with an economic optimization model for nutrient pollution of surface and ground water within an agricultural watershed. Although firms are homogeneous in abatement costs, differences in spatial location leave uniform instruments unable to achieve the water quality goal efficiently. An ambient tax/subsidy scheme can achieve the water quality goal efficiently but the informational requirements will be excessive in most situations where the transport mechanisms for residuals are dependent upon the practices of independent decision making units.  相似文献   
147.
近代上海的开埠带来了国内市场的变化。19世纪60年代后,中国沿海与长江各口岸相继对外开放,沿海沿江贸易航运业快速发展,形成埠际贸易网络。上海转口贸易通过埠际转运网络的各级市场影响中国长江流域和华北、东北、西南、华南地区。在此过程中,上海与近代中国其他重要的通商口岸之间形成了固定的埠际转运网络,上海埠际贸易网络日益呈现出结构化特征。  相似文献   
148.
The paper studies the characteristics of the evolution over time of modal split for a transport system in which various modes compete with each other and face the freight flow increase in different ways. It is shown that the modal split evolution is constituted by a sequence of time periods, in each of which the dynamic characteristics of the system are different. An equilibrium, stable or unstable, is reached after a transition phase, whose length depends on the characteristics of the system, and in some cases exceeds the length of the period, so that an equilibrium is not reached.  相似文献   
149.
The Locomotive Assignment Problem (LAP) is a class of planning and scheduling problems solved by assigning a fleet of locomotives to a network of trains. In the planning versions of the LAP, the type of consist (a group of linked locomotives) assigned to each train in a given schedule is determined. We introduce an optimization model (called consists selection) that precedes the planning LAP solution and determines the set of consist types. This selection leads to solutions that are characterized by potential savings in terms of overall fueling cost and are easier to handle in the routing phase.  相似文献   
150.
设为首页 | 免责声明 | 关于勤云 | 加入收藏

Copyright©北京勤云科技发展有限公司  京ICP备09084417号