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   10716篇
  免费   234篇
财政金融   1722篇
工业经济   799篇
计划管理   1839篇
经济学   2104篇
综合类   85篇
运输经济   70篇
旅游经济   150篇
贸易经济   1657篇
农业经济   537篇
经济概况   1983篇
信息产业经济   1篇
邮电经济   3篇
  2023年   58篇
  2021年   74篇
  2020年   129篇
  2019年   198篇
  2018年   251篇
  2017年   242篇
  2016年   237篇
  2015年   151篇
  2014年   285篇
  2013年   1002篇
  2012年   348篇
  2011年   409篇
  2010年   309篇
  2009年   346篇
  2008年   318篇
  2007年   290篇
  2006年   263篇
  2005年   238篇
  2004年   237篇
  2003年   241篇
  2002年   207篇
  2001年   214篇
  2000年   215篇
  1999年   180篇
  1998年   172篇
  1997年   158篇
  1996年   162篇
  1995年   150篇
  1994年   131篇
  1993年   157篇
  1992年   163篇
  1991年   141篇
  1990年   149篇
  1989年   143篇
  1988年   150篇
  1987年   119篇
  1986年   136篇
  1985年   168篇
  1984年   156篇
  1983年   135篇
  1982年   140篇
  1981年   136篇
  1980年   127篇
  1979年   99篇
  1978年   119篇
  1977年   92篇
  1976年   90篇
  1975年   66篇
  1974年   61篇
  1973年   66篇
排序方式: 共有10000条查询结果,搜索用时 8 毫秒
91.
Sustainable technology development implies large changes in technological systems. The illustrative process ‘hydrogen fuel cell in a boat’ is used here as an example of a learning process concerning a transition towards a hydrogen economy. Theoretically the concepts of constructive technology assessment, back-casting and social niche management are combined in this approach.  相似文献   
92.
This study investigates productivity growth in broad-acre agriculture in Western Australia. Tornqvist indices of three output groups (crops, sheep products and other) and five input groups (livestock, materials and services, labour, capital and land) are constructed and discussed. Indices of total output and total inputs are also derived and used to form an index of total factor productivity, that is observed to grow at an average annual rage of 2·7%. The input and output indices are also used in the estimation of output supply and input demand equations, derived from a flexible profit function. The Generalized McFadden functional form is used, because it is possible to impose global curvature upon it without loss of flexibility. Asymptotic chi-square tests reject the hypotheses of Hicks-neutral technical change in inputs and in outputs. Technical change is observed to be ‘materials and services’ saving relative to the other input groups, and also appears to favour wool and sheepmeat production relative to the other output groups.  相似文献   
93.
This paper examines the relationship between the passage of six types of corporate antitakeover provisions (supermajority, classified boards, fair-price, reduction in cumulative voting, anti-greenmail and poison pills) and stockholder wealth. Our event study from a sample of 381 firms that adopted 486 antitakeover provisions in the 1984 to 1988 period indicates a strongly negative effect on stockholder wealth, supporting the management entrenchment view of the antitakeover provisions. Moreover, the empirical results of this paper indicate that the market reacts equally negatively to both non-operating provisions that require stockholder approval and to operating provisions that do not require stockholder approval. However, separate analyses of the antitakeover provisions provide some support for the argument that stockholders discriminate between individual provisions.  相似文献   
94.
95.
A novel gelatin system for use in oil spills at sea provides rapid immobilization of liquids upon demand.  相似文献   
96.
97.
Plant-based precision nitrogen fertilizer application technologies have been developed as a way to predict and precisely meet nitrogen needs. Equipment necessary for precision application of nitrogen, based on sensing of growing wheat plants in late winter, is available commercially, but adoption has been slow. This article determines the expected profit from using a plant-sensing system to determine winter wheat nitrogen requirements. We find that plant-sensing systems have the potential to be more profitable than traditional nonprecise systems, but the existing system simulated was roughly breakeven with a traditional system.  相似文献   
98.
99.
100.
To achieve sustainability in heritage tourism, tourists should be placed at the heart of the management and planning processes. Indicators and standards-based frameworks were developed in the field of outdoor recreation management to manage and measure crowding and other problematic issues in parks and related areas. Using normative theory and visual research methods, this article aims to examine crowding standards of tourists at Petra Archaeological Park, and compare these standards between the types of heritage tourists suggested by a model developed by Bob McKercher. Results showed that tourists’ acceptability levels go down with an increasing number of tourists, and tourists who are highly motivated to visit heritage sites (i.e. purposeful and sightseeing heritage tourists) had the most restrictive acceptable number of tourists at the park. The normative standards formulated in this article provided a guidance to manage crowding at Petra.  相似文献   
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