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   9233篇
  免费   1497篇
  国内免费   107篇
财政金融   1048篇
工业经济   712篇
计划管理   2198篇
经济学   1976篇
综合类   1108篇
运输经济   199篇
旅游经济   125篇
贸易经济   1902篇
农业经济   686篇
经济概况   882篇
邮电经济   1篇
  2024年   5篇
  2023年   28篇
  2022年   135篇
  2021年   319篇
  2020年   284篇
  2019年   542篇
  2018年   280篇
  2017年   429篇
  2016年   411篇
  2015年   612篇
  2014年   735篇
  2013年   903篇
  2012年   854篇
  2011年   797篇
  2010年   748篇
  2009年   640篇
  2008年   655篇
  2007年   591篇
  2006年   573篇
  2005年   448篇
  2004年   271篇
  2003年   176篇
  2002年   165篇
  2001年   144篇
  2000年   61篇
  1999年   9篇
  1998年   5篇
  1997年   2篇
  1996年   1篇
  1995年   4篇
  1994年   1篇
  1991年   3篇
  1989年   1篇
  1987年   4篇
  1981年   1篇
排序方式: 共有10000条查询结果,搜索用时 151 毫秒
1.
自然资源规划评估在实践探索中形成了一套“三期十步法”的评估模式。文章以总结国内外规划评估经验为基础,具体阐述自然资源“十三五”规划评估开展的基本内容和任务,并结合实践中存在的突出问题,提出完善“十四五”规划评估的建议:一是推动自然资源规划评估标准化建设;二是构建完善的评估数据信息系统;三是建立良好的评估运行监测机制;四是加大规划评估的宣传引导。  相似文献   
2.
郭震宇 《价值工程》2021,40(17):80-81
本文介绍了连续复合钢筋混凝土路面的性能、结构原理和特性,并探讨了施工过程要求以及施工要点.通过一些研究分析可以看出,使用复合式沥青路面,能够在使用过程中有着足够的承载力,并且该方法的应用还可以减小了沥青使用的结构厚度,提高了整体路面工程的抗变形能力.  相似文献   
3.
为了提高双离合变速器在车辆上的换挡品质,提升电气化换挡执行机构的工作效率,给出执行机构性能与换挡品质评价准则;通过两种不同双离合变速器电控电动执行机构的工作原理与性能分析,基于MATLAB数值仿真方法优化出最高效率进行试验.基于车辆6个维度的换挡工况对二者所搭载的变速器分别进行试验与CAN线数据采集,对比研究两种机构优缺点,通过雷达图的方式进行优劣说明.结果表明,两种执行机构传动效率可达70%且换挡品质相当.可见Tip in tip out工况对二者要求最为严格.  相似文献   
4.
郭伟  柴喜洲  刘琪 《价值工程》2021,40(3):129-131
糯扎渡水电站坝后量水堰在运行过程中为强化量水堰功能,截断坝基渗透水流,实施量水堰防渗工程,形成整体的枢纽工程防渗帷幕体系。本文通过对量水堰防渗工程施工关键技术的总结,介绍了在防渗标准高、施工难度大、工期紧的情况下高效高质完成防渗工程的具体施工方法,可为今后类似水利水电工程施工提供经验和借鉴。  相似文献   
5.
建筑企业为了进一步扩大盈利空间,在项目运行期间于造价管理工作中引入集成管理理论,采用全过程造价咨询管控方式,提升项目成本管控能力。论文考虑到造价管理对建筑企业的重要性,着重介绍集成管理理论在全过程造价咨询领域的应用方式。  相似文献   
6.
We examine factors affecting the adoption of improved cassava varieties of 217 households in the Cauca Department in southwest Colombia. Using DNA fingerprinting through Single Nucleotide Polymorphisms (SNPs), we identified different cultivars in farmers fields. We also used this information to remove possible bias in the adoption model that could have resulted from a misclassification of improved varieties (IVs). As a result, we found that farmers substantially overestimate their use of IVs and there are important differences in the determinants of adoption between farmer self‐identification and DNA fingerprinting. This finding implies that the incorporation of DNA fingerprinting in IV adoption studies is important to ensure the accuracy of future agricultural economic research and the relevance of subsequent policy recommendations.  相似文献   
7.
This study examines how relationship innovation can be developed in global collaborative partnerships (alliances, joint ventures, mergers, and acquisitions). The recently emerging theory of big data analytics linked with traditional organizational powers has attracted a growing interest, but surprisingly little research has been devoted to this important and complex topic. Therefore, after developing the theoretical foundations, our study empirically quantifies the links between the theoretical constructs based on the data collected from chief executive officers, managing directors, and heads of departments who work in contemporary global data‐and‐information driven collaborative partnerships. The results from structural equation modeling indicate that the relationship innovation depends on the power of big data analytics and non‐mediated powers (NMP, expert and referent). The power of big data analytics also mediates the correlation between NMP and relationship innovation. However, mediated powers (coercive and manipulative) negatively affect the power of big data analytics and relationship innovation. The interaction effects further depict that analytically powered partnerships have better relationship innovation compared with those which focus less on the analytical power. Consequently, the contributions of this study provide a deeper understanding of mechanisms of how modern collaborative partnerships can use big data analytics and traditional organizational powers to co‐create relationship innovation.  相似文献   
8.
This study examines whether difficult targets and quality indicators in executives' pay‐for‐performance (P4P) plans affect performance. The impact of target‐setting and P4P plans on quality improvement in the public sector is unclear. The Ontario government initiated the Quality Improvement Plan (QIP), which requires hospitals to set targets for quality indicators annually and link executive pay to target achievement since 2011. Analyzing Health Quality Ontario's database and hospitals' 2012–2013 QIPs, this study shows greater quality improvement in hospitals with difficult targets than hospitals with easy targets or without assigned targets; however, the positive impact disappears for high‐performance hospitals relative to their peers. We find no significant effect of the use of quality indicators in executives' P4P plans on quality improvement. Copyright © 2018 ASAC. Published by John Wiley & Sons, Ltd.  相似文献   
9.
We propose parametric copulas that capture serial dependence in stationary heteroskedastic time series. We suggest copulas for first‐order Markov series, and then extend them to higher orders and multivariate series. We derive the copula of a volatility proxy, based on which we propose new measures of volatility dependence, including co‐movement and spillover in multivariate series. In general, these depend upon the marginal distributions of the series. Using exchange rate returns, we show that the resulting copula models can capture their marginal distributions more accurately than univariate and multivariate generalized autoregressive conditional heteroskedasticity models, and produce more accurate value‐at‐risk forecasts.  相似文献   
10.
This paper considers a duopoly market with horizontally differentiated system goods to examine system owners' behaviors under supporting software delegation, in which owners of system firms use varieties of supporting software, coupled with profit, to evaluate their managers' performance. Supporting software delegation seems to induce managers to act more aggressively in price competition than sales delegation does; however, we prove that if two systems are compatible and the varieties of supporting software are determined by hardware owners' overall expenditure amount on software, then supporting software delegation is equivalent to sales delegation. Owners of system firms induce their managers to act less aggressively in hardware price competition by offering contracts with a negative weight on varieties of supporting software under supporting software delegation. We find that stronger network externalities do not reverse system owners' contracting behaviors under supporting software delegation. Finally, it is worth mentioning that hardware technologies are static in this paper. In other words, dynamic changes such as hardware evolution are not considered in our analysis.  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