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   145970篇
  免费   4230篇
  国内免费   134篇
财政金融   26410篇
工业经济   12222篇
计划管理   24009篇
经济学   30558篇
综合类   3052篇
运输经济   1100篇
旅游经济   2577篇
贸易经济   24848篇
农业经济   6799篇
经济概况   18492篇
信息产业经济   14篇
邮电经济   253篇
  2021年   1199篇
  2020年   1894篇
  2019年   2526篇
  2018年   2406篇
  2017年   2654篇
  2016年   2844篇
  2015年   2502篇
  2014年   3991篇
  2013年   15957篇
  2012年   5170篇
  2011年   5385篇
  2010年   4952篇
  2009年   5217篇
  2008年   4852篇
  2007年   4138篇
  2006年   4560篇
  2005年   4313篇
  2004年   3357篇
  2003年   3039篇
  2002年   3001篇
  2001年   2729篇
  2000年   2555篇
  1999年   2433篇
  1998年   2249篇
  1997年   2302篇
  1996年   2167篇
  1995年   1948篇
  1994年   1977篇
  1993年   1935篇
  1992年   1987篇
  1991年   1864篇
  1990年   1771篇
  1989年   1652篇
  1988年   1581篇
  1987年   1578篇
  1986年   1658篇
  1985年   2407篇
  1984年   2282篇
  1983年   2075篇
  1982年   1942篇
  1981年   1876篇
  1980年   1846篇
  1979年   1775篇
  1978年   1609篇
  1977年   1618篇
  1976年   1368篇
  1975年   1268篇
  1974年   1183篇
  1973年   1186篇
  1972年   894篇
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
1.
We collected 469 frontal face images of Ukrainian cabinet ministers who were in office in 2000–2020. For each image, the minister's body mass index was estimated using a computer vision algorithm. The time series of median estimated body mass index of cabinet ministers co-moves over time with two existing measures of corruption – World Bank worldwide governance indicator Control of Corruption, and the discrepancy between the quantity of luxury wristwatches exported from Switzerland to Ukraine (reported by Swiss statistics) and the corresponding quantity imported by Ukraine from Switzerland (reported by Ukrainian statistics).  相似文献   
2.
以我国各省知识产权保护制度为研究对象,创新性地将探索性空间数据分析方法与社会网络分析方法相结合,基于地理邻近视角,验证了区域知识产权保护的空间相关性、空间集聚特征和空间溢出效应。同时,突破地理近邻效应的局限,解析区域知识产权保护的空间关联特征。结果表明:我国各省知识产权保护具有全局自相关性,相似地区间存在空间集聚效应,不同发展程度地区的空间关联性质不同;网络化后的区域知识产权保护各节点间联系紧密、网络结构稳定,并且可以确定核心行动者和边缘行动者角色;长三角、珠三角、环渤海等较发达地区与其它地区之间存在较多溢出关系。  相似文献   
3.
马威 《价值工程》2021,40(23):174-176
导航过程中的路径规划与引导,不仅关系算法,更取决于所用的路网数据.路网有诸多属性和关系,关系到路径规划速度和引导合理性的最重要特征之一就是经路等级,又称拓扑阶层.本文拟从路径规划的原理出发,引出导航电子地图制作中路网经路等级设计的必要性,继而给出经路等级设计的一般规则以及设计方法,最后通过北京、天津、重庆等多个城市路网经路等级的设计结果,验证了所提出的设计方法的可行性和合理性.  相似文献   
4.
5.
Prior research has shown that the well-being of employees engaged in intensive work can vary with the discretion their jobs afford regarding how and when to carry out the work. This article explores a different avenue. It argues that well-being also varies with employees’ individual motives for working intensively. The article introduces self-determination theory to the domain of work intensity and focuses on two hypotheses. The first is whether intensive work driven by explicit or implicit incentives is more positively associated with an employee's job satisfaction than intensive work driven by job demands. The second is whether intensive work driven by intrinsic motives is more positively associated with job satisfaction than that driven by explicit or implicit incentives. In both these cases, the article also examines whether equivalent effects exist on (reduced) quit intentions. Original data from a major Greek grocery chain provide corroborative evidence that is robust to a rich set of covariates, including increasingly demanding adjustments for job discretion. The findings contribute to a more complete understanding of why differences in well-being exist among employees performing intensive work, with implications for workers and employers.  相似文献   
6.
We investigate the impact of housing wealth, credit availability and financial distress on college enrolment decisions. We find that housing wealth is negatively related to enrolment in public schools and positively related to enrolment in private schools. This evidence suggests that, on average, students substituted away from private schools towards public institutions during the recent financial crisis.  相似文献   
7.
8.
The main objective of this paper it to model the dynamic relationship between global averaged measures of Total Radiative Forcing (RTF) and surface temperature, measured by the Global Temperature Anomaly (GTA), and then use this model to forecast the GTA. The analysis utilizes the Data-Based Mechanistic (DBM) approach to the modelling and forecasting where, in this application, the unobserved component model includes a novel hybrid Box-Jenkins stochastic model in which the relationship between RTF and GTA is based on a continuous time transfer function (differential equation) model. This model then provides the basis for short term, inter-annual to decadal, forecasting of the GTA, using a transfer function form of the Kalman Filter, which produces a good prediction of the ‘pause’ or ‘levelling’ in the temperature rise over the period 2000 to 2011. This derives in part from the effects of a quasi-periodic component that is modelled and forecast by a Dynamic Harmonic Regression (DHR) relationship and is shown to be correlated with the Atlantic Multidecadal Oscillation (AMO) index.  相似文献   
9.
10.
We present a longitudinal qualitative case study to elaborate on how a social venture forms reference points for social performance. Although organizations increasingly use various social performance targets to direct their operations, the scholarly knowledge on social performance reference points remains limited. We make use of the prior accounting literature and draw on the idea of compromising accounts to discuss how provisional and performative metrics can have a significant role in how organizations develop new ways to evaluate their social performance. Given that the social performance reference point criteria are ambiguous and the corresponding referents malleable, performative accounts are helpful as they can intervene in the organizational life by making particular things visible, providing space for interpretations, and facilitating discussion, thus creating temporary settlements and enabling opportunities for productive compromises between different organizational groups and evaluative principles. The recursive feedback loops between reference point referents, criteria and accounting artefacts help the organization to make sense of its own social performance and interpret the associated performance feedback, and thereby provide ground for organizational decisions on further action. Moreover, we discuss how imperfect accounts can be useful for social businesses in their pursuit of developing their activities and achieving social impact.  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