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   23418篇
  免费   949篇
  国内免费   376篇
财政金融   1340篇
工业经济   1233篇
计划管理   5954篇
经济学   4311篇
综合类   2311篇
运输经济   405篇
旅游经济   816篇
贸易经济   2928篇
农业经济   2815篇
经济概况   2627篇
邮电经济   3篇
  2024年   81篇
  2023年   450篇
  2022年   509篇
  2021年   676篇
  2020年   920篇
  2019年   658篇
  2018年   593篇
  2017年   819篇
  2016年   746篇
  2015年   799篇
  2014年   1708篇
  2013年   2207篇
  2012年   1952篇
  2011年   2339篇
  2010年   1742篇
  2009年   1489篇
  2008年   1530篇
  2007年   1366篇
  2006年   1136篇
  2005年   862篇
  2004年   632篇
  2003年   365篇
  2002年   255篇
  2001年   211篇
  2000年   159篇
  1999年   92篇
  1998年   98篇
  1997年   64篇
  1996年   56篇
  1995年   47篇
  1994年   36篇
  1993年   21篇
  1992年   18篇
  1991年   18篇
  1990年   9篇
  1989年   9篇
  1988年   5篇
  1987年   5篇
  1986年   9篇
  1985年   12篇
  1984年   13篇
  1983年   12篇
  1982年   8篇
  1981年   3篇
  1980年   2篇
  1979年   2篇
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
31.
Several consumer studies have shown considerable market potential for sustainable meat products, however, their markets shares are still marginal. In Germany, the sustainable aspects “organic,” “local origin,” and “animal welfare” are of special interest. To obtain a precise overview of potential target groups for these meat categories and their choice of store format, 620 German consumers were surveyed on their attitudes toward sustainable meat production and their shopping behavior. First, target groups based on consumers’ attitudes were identified by cluster analysis, taking into account possible overlaps. Consumers were also clustered by their store format choice and their preferred type of meat packaging. A cross tabulation of the results then provided insights into which store format and type of meat packaging is preferred by the target groups for sustainable meat products. Due to overlaps found in the target groups, the existence of important subgroups was shown. Amongst the target groups, only a slight preference for unpackaged meat products was found. Basically, the offer of sustainable meat products appears of interest for all store formats, with particular emphasis on supermarkets. The results of this study can support producers and retailers developing new and tailored marketing strategies for sustainable meat products.  相似文献   
32.
Research on productive efficiency at the firm level has developed as an important and active strand of research the last decades, both within operations research, management science and economics. Two apparently different definitions of efficiency are examined, but it is shown that when both estimation methods are based on solving linear programming problems the definitions of efficiency are identical. The purpose of the paper is to give the basic ideas of efficiency analyses using DEA as a tool for researchers not so familiar with efficiency analysis and DEA. The concept of shadow prices is given special attention.  相似文献   
33.
This article tests the hypotheses of convergence to a single level of total factor productivity (TFP), and a steady state of TFP growth rate in China’s agricultural sector. Based on multilateral TFP estimates we found that China’s agricultural sector has rebounded in recent years from a slower TFP growth in the 2005–2007 period. While convergence test results confirm a “catch-up” effect that provinces with lower TFP levels tend to grow faster than others, estimated rates of β convergence are conditional on how we capture the heterogeneity effect across regions. The rates of β convergence range from 0.016 to 0.039 under different model specifications. Estimates show that higher growth rates of educational attainment, R&D, and intermediate goods density (per unit of labor) can enhance TFP growth. Unfortunately, there is no evidence of an overall σ convergence, indicating that TFP levels are not converging except in the South region. It implies that to catch up with leading provinces, it would require extra efforts for those lagging behind by increasing their region-specific research investment, promoting rural educational attainment, and enhancing embodied technical change.  相似文献   
34.
张震  郑檩  张雷  靳晔 《科技和产业》2021,21(2):243-248
为研究自动涂胶系统的胶枪最优材质、最佳热源位置和最佳测温位置,利用ANSYS Workbench软件对自粘胶胶枪进行数值模拟.通过分析不同材质胶枪的温度场分布情况,结合经济性和加热性能,选定最优胶枪基材.同时分析得出加热自粘胶至工作温度的时间和保持工作温度的加热功率,确定了热源和测温点位置,拟定了升温策略.进行自粘胶胶枪加热试验,验证了仿真分析结果的准确性.  相似文献   
35.
This two‐part case allows for maximum student engagement through preparation, in‐class discussion, and through a Part B case that is part of the Teaching Note. Through this case, students work to identify possible fraud schemes, plan an investigation, and perform horizontal analysis calculations. Students will learn about the concept of ethical hacking, red flag identification, internal control weaknesses, and investigation considerations for fraud schemes. Further, in‐class planning for next steps and investigation can occur, providing an opportunity for group work and in‐depth learning. This case offers flexibility for instructors in that it can be covered over one class or multiple classes, or can be assigned as an independent or group assignment. This teaching note provides an overview of the case along with guidance for teaching this case.  相似文献   
36.
This study investigates how pesticide use by neighbouring farmers affects a given farmer's pesticide use. Although it is common knowledge that pesticide use has spatial externalities, few empirical economic studies explicitly analyse this issue. Applying a spatial panel econometric model to plot‐level panel data for Bohol, Philippines, this study shows that pesticide use, especially for herbicides, is spatially correlated, although there is no statistically significant spatial correlation in unobserved shocks. This implies that farmers apply pesticides by referring to the behaviour of neighbouring farmers rather than responding directly to the intensity of their own infestation.  相似文献   
37.
[目的]对甘孜州各县市的发展状况进行研究探讨,为区域可持续发展策略的制定实施提供科学依据,对提升县域发展水平和发展质量具有重要意义。[方法]建立涵盖经济、社会、资源环境三大模块共计24项指标的评价体系,选取发展较快的2007—2014年为研究时段,运用极差法、改进熵值法、耦合协调度模型与GIS工具,对甘孜州各县市的发展水平进行综合评价与分析。[结果](1)全州综合发展水平指数平均值为0. 500 8,发展水平整体较低,其中康定市得分最高,石渠县最低,县市之间呈现两级分化。(2) 2007—2014年全州综合发展指数平均增幅0. 262 6,年均增速13. 77%,所有县市均处于上升过程,但县市之间增速不一,发展差距逐步扩大。(3)全州发展协调度平均值为0. 390 5,协调度较低,各县市均处于轻度失调或濒临失调水平。(4)发展水平、活力、协调度较高县市均集聚于州东部和南部,尤以东路片区最为典型。[结论]下一阶段需依据各县市实际,立足优势,制定实施合理的发展规划,缩小区域差异,提升综合发展水平。  相似文献   
38.
We survey the methodological advances in DEA over the last 25 years and discuss the necessary conditions for a sound empirical application. We hope this survey will contribute to the further dissemination of DEA, the knowledge of its relative strengths and weaknesses, and the tools currently available for exploiting its full potential. Our main points are illustrated by the case of the DEA study used by the regulatory office of the Dutch electricity sector (Dienst Toezicht Elektriciteitswet; Dte) for setting price caps.  相似文献   
39.
旅游收入是旅游经济活动的重要内容,它一方面反映了旅游者的旅游需求通过旅游经营者的旅游供给而不断得到满足,另一方面又体现着旅游产业部门和企业在产经营活动的价值运行与价值实现。旅游收入与分配是旅游经济运行的前提,对其进行考察分析,是十分重要的。本章从收入和分配两个方面入手,对旅游收入分类、指标、旅游企业收入和分配以及旅游收入乘数的作用等进行了分析和阐述。  相似文献   
40.
Selecting the most promising candidates to fill an open position can be a difficult task when there are many applicants. Each applicant achieves certain performance levels in various categories and the resulting information can be overwhelming. We demonstrate how data envelopment analysis (DEA) can be used as a fair screening and sorting tool to support the candidate selection and decision-making process. Each applicant is viewed as an entity with multiple achievements. Without any a priori preference or information on the multiple achievements, DEA identifies the non-dominated solutions, which, in our case, represent the “best” candidates. A DEA-aided recruiting process was developed that (1) determines the performance levels of the “best” candidates relative to other applicants; (2) evaluates the degree of excellence of “best” candidates’ performance; (3) forms consistent tradeoff information on multiple recruiting criteria among search committee members, and, then, (4) clusters the applicants.  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