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   55650篇
  免费   2283篇
  国内免费   604篇
管理学   2960篇
劳动科学   13篇
民族学   435篇
人才学   14篇
人口学   996篇
丛书文集   5295篇
理论方法论   1675篇
综合类   38342篇
社会学   1649篇
统计学   7158篇
  2024年   157篇
  2023年   463篇
  2022年   635篇
  2021年   708篇
  2020年   901篇
  2019年   1022篇
  2018年   1048篇
  2017年   1298篇
  2016年   1278篇
  2015年   1459篇
  2014年   2969篇
  2013年   4303篇
  2012年   3610篇
  2011年   3906篇
  2010年   3287篇
  2009年   3319篇
  2008年   3444篇
  2007年   3979篇
  2006年   3815篇
  2005年   3406篇
  2004年   3055篇
  2003年   2783篇
  2002年   2274篇
  2001年   1904篇
  2000年   1123篇
  1999年   514篇
  1998年   301篇
  1997年   291篇
  1996年   222篇
  1995年   221篇
  1994年   177篇
  1993年   138篇
  1992年   123篇
  1991年   96篇
  1990年   64篇
  1989年   74篇
  1988年   54篇
  1987年   30篇
  1986年   19篇
  1985年   17篇
  1984年   12篇
  1983年   13篇
  1982年   8篇
  1981年   4篇
  1980年   3篇
  1979年   5篇
  1978年   3篇
  1977年   1篇
  1975年   1篇
排序方式: 共有10000条查询结果,搜索用时 31 毫秒
31.
郑立新  罗鹏 《云梦学刊》2020,(1):115-124
农民是农业和农村的主体,也是乡村振兴的内生因素,发挥农民主体作用对实施乡村振兴战略意义重大。当前农民对乡村振兴关注度和支持度较高,农民的主体作用发挥成为乡村振兴的根本动力。但现实中,农民主体作用也受到诸如农业综合效益较低、农民自身思想文化和能力素质不高、管理机制滞后及基础条件薄弱等多方面的因素制约,需要党委、政府综合施策,采取完善乡村治理、健全政策扶持、建立引导机制、补齐短板缺陷、加强培育培训等一系列政策措施,尊重、引导、激励和支持农民自我管理、自我发展,激发农民的主动性、积极性、创造性。  相似文献   
32.
China’s pension reform during the past three decades has allowed a majority of China’s population to be covered by a pension scheme. Of particular note has been the New Rural Pension Scheme (NRPS), a voluntary programme introduced starting in 2009. One goal of our analysis is to assess that pension scheme, using a variety of sources of information including data drawn from recent (2013 and 2015) nationwide China Health and Retirement Longitudinal Surveys (CHARLS). Our analysis involves an exploration of differences between the generosity and structure of the NRPS and other pension schemes currently in place. We also explore the feasibility of reforming the current “quasi-social pension” component of the NRPS by substituting a universal non-contributory social pension pillar. In connection with our assessment of the NRPS, we note the unusually low benefit levels for rural China.  相似文献   
33.
Reviews     
Abstract

Michelle DeMars reviews The Indispensable Academic Librarian: Teaching and Collaborating for Change; Norma Durian reviews The Library Outreach Casebook; Trina Boykin Nolen reviews Licensing Digital Content: A Practical Guide for Librarians, Third Edition.  相似文献   
34.
系统总结了在伸展构造背景下,导致反映构造特征的地层倾角模式复杂化的多种因素。沉积相的不同、岩性变化、井眼状况和测井作业时间等多种因素都可能使地层倾角资料复杂化。进一步指出在拉张盆地中,进行倾角资料的构造解释,必须了解其构造样式的多样性和复杂性,解释存在的多解性。重点解剖了铲式断层在横剖面情况下,对于不同构造位置下的倾角模式。详细分析了一个倾角模式对应多种构造样式的倾角构造解释实例。倾角资料的构造解释应是综合解释,既要综合井筒的相关地质资料,又要综合测井与地质知识,还必须考虑综合地震资料。  相似文献   
35.
We propose testing procedures for the hypothesis that a given set of discrete observations may be formulated as a particular time series of counts with a specific conditional law. The new test statistics incorporate the empirical probability-generating function computed from the observations. Special emphasis is given to the popular models of integer autoregression and Poisson autoregression. The asymptotic properties of the proposed test statistics are studied under the null hypothesis as well as under alternatives. A Monte Carlo power study on bootstrap versions of the new methods is included as well as real-data examples.  相似文献   
36.
Generally, the semiclosed-form option pricing formula for complex financial models depends on unobservable factors such as stochastic volatility and jump intensity. A popular practice is to use an estimate of these latent factors to compute the option price. However, in many situations this plug-and-play approximation does not yield the appropriate price. This article examines this bias and quantifies its impacts. We decompose the bias into terms that are related to the bias on the unobservable factors and to the precision of their point estimators. The approximated price is found to be highly biased when only the history of the stock price is used to recover the latent states. This bias is corrected when option prices are added to the sample used to recover the states' best estimate. We also show numerically that such a bias is propagated on calibrated parameters, leading to erroneous values. The Canadian Journal of Statistics 48: 8–35; 2020 © 2019 Statistical Society of Canada  相似文献   
37.
Simulation results are reported on methods that allow both within group and between group heteroscedasticity when testing the hypothesis that independent groups have identical regression parameters. The methods are based on a combination of extant techniques, but their finite-sample properties have not been studied. Included are results on the impact of removing all leverage points or just bad leverage points. The method used to identify leverage points can be important and can improve control over the Type I error probability. Results are illustrated using data from the Well Elderly II study.  相似文献   
38.
农村基层党组织是党在农村的神经末梢,也是党的路线、方针、政策的"终端"推动者和实践者。现阶段农村党组织建设面临新兴组织不断涌现与党组织作用削弱的不适应,"权力和资源缺失"与服务刚性增强的不适应,村民自治进一步发展与群众政治参与欠充分的不适应,群众诉求多样化与满足渠道单一的不适应,部分党员党性不强、意识淡化与始终保持先进性的要求不适应等问题。在加强以党支部为核心的农村基层组织建设的"莱西会议精神"指导下,全面深化农村基层党组织建设:思想上高度认识是前提,加强支部建设是核心,坚持法治、完善村民自治是重点,紧扣服务、创新制度是关键,统筹协调、综合配套是保障。  相似文献   
39.
Previous research has evaluated public risk perception and response to a natural hazards in various settings; however, most of these studies were conducted either with a single scenario or after a natural disaster struck. To better understand the dynamic relationships among affect, risk perception, and behavioral intentions related to natural disasters, the current study implements a simulation scenario with escalating weather intensity, and includes a natural experiment allowing comparison of public response before and after a severe tornado event with extensive coverage by the national media. The current study also manipulated the display of warning information, and investigated whether the warning system display format influences public response. Results indicate that (1) affect, risk perception, and behavioral intention escalated as weather conditions deteriorated, (2) responses at previous stages predicted responses at subsequent stages of storm progression, and (3) negative affect predicted risk perception. Moreover, risk perception and behavioral intention were heightened after exposure to the media coverage of an actual tornado disaster. However, the display format manipulation did not influence behavioral responses. The current study provides insight regarding public perception of predisaster warnings and the influence of exposure to media coverage of an actual disaster event.  相似文献   
40.
Not only ETO (Engineering to Order), but even serial production industry should know how to deal with projects and their schedule: plant commissioning, shutdown, introducing new products and similar circumstances should be managed with adequate planning and resource allocation techniques to create a schedule useful in decision making during the execution. The current complex reality, with evolving technologies and fierce pressure to reach the market as soon as possible, pushes the project managers to use more advanced techniques than waterfall planning, such as agile or lean. It also requires them to take a holistic view and manage concurrent tasks in complex projects. The contributions of this paper are two: the proposal to control specific parallel groups of waterfall activities under uncertain environments, which can lead to iterations and reworks, as a single concurrent Activity Managed by Kanban Methods (AMKM). This activity can be subsequently embedded into traditional scheduling approaches as CPM-PERT. The second contribution is the feasibility of its application in industrial environments due to the affordability of simulation software. Two use cases are shown as evidence. It is not a disruptive proposal, but a kaizen action based on very mature technologies. Finally, it is suggested some improvements to be implemented in Project Management Software due to this ‘kaizen’ proposal.  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