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   17370篇
  免费   720篇
  国内免费   223篇
管理学   1870篇
劳动科学   2篇
民族学   87篇
人才学   3篇
人口学   331篇
丛书文集   988篇
理论方法论   420篇
综合类   8721篇
社会学   558篇
统计学   5333篇
  2024年   21篇
  2023年   126篇
  2022年   222篇
  2021年   251篇
  2020年   370篇
  2019年   467篇
  2018年   523篇
  2017年   663篇
  2016年   555篇
  2015年   590篇
  2014年   950篇
  2013年   2165篇
  2012年   1261篇
  2011年   1122篇
  2010年   903篇
  2009年   908篇
  2008年   979篇
  2007年   976篇
  2006年   922篇
  2005年   802篇
  2004年   707篇
  2003年   632篇
  2002年   567篇
  2001年   497篇
  2000年   266篇
  1999年   188篇
  1998年   97篇
  1997年   103篇
  1996年   79篇
  1995年   70篇
  1994年   48篇
  1993年   43篇
  1992年   37篇
  1991年   40篇
  1990年   24篇
  1989年   18篇
  1988年   15篇
  1987年   9篇
  1986年   7篇
  1985年   19篇
  1984年   14篇
  1983年   16篇
  1982年   8篇
  1981年   4篇
  1980年   9篇
  1979年   10篇
  1978年   6篇
  1977年   2篇
  1976年   1篇
  1975年   1篇
排序方式: 共有10000条查询结果,搜索用时 46 毫秒
931.
The monetary policy targets the short rates; however, during zero interest rate policy (ZIRP), the short end of the yield curve cannot serve as a policy instrument. Relying on the joint yields-macro latent factors model, this study empirically examines the effect of monetary policy stances on term structure and the possible feedback effect on the real sector using the Japanese experience of ZIRP. The analysis indicates that it is the entire term structure that transmits the policy shocks to the real economy rather than the yield spread only. The monetary policy signals pass through the yield curve level and slope factors to stimulate the economic activity. The curvature factor, besides reflecting the cyclical fluctuations of the economy, acts as a leading indicator for future inflation. In addition, policy influence tends to be low as the short end becomes segmented toward medium/long-term of the yield curve. Furthermore, volatility in bond markets is found to be asymmetrically affected by positive and negative shocks and long end tends to be less sensitive to stochastic shocks than the short maturities. The expectation hypothesis of the term structure does not hold during the ZIRP period.  相似文献   
932.
基于模型试验,对堆载诱发型边坡滑坡的变形机理及演化过程进行研究。研究结果表明: (1)堆载诱发型滑坡的变形演化规律可归纳为:后缘压缩阶段→蠕动变形阶段→加速滑动阶段→剧滑阶段,且剧滑启动之前的加速变形过渡时间极短;(2)利用FLAC3D软件进行堆载滑坡演化过程的动态数值分析,模拟过程中坡体应力场和位移场的演化特征表现为从上向下逐步贯通,与模型边坡破坏过程相符;(3)堆载诱发型滑坡破坏过程历时短、突发性强,在坡脚产生持续位移时即应做出滑坡预警。  相似文献   
933.
The cumulative incidence function plays an important role in assessing its treatment and covariate effects with competing risks data. In this article, we consider an additive hazard model allowing the time-varying covariate effects for the subdistribution and propose the weighted estimating equation under the covariate-dependent censoring by fitting the Cox-type hazard model for the censoring distribution. When there exists some association between the censoring time and the covariates, the proposed coefficients’ estimations are unbiased and the large-sample properties are established. The finite-sample properties of the proposed estimators are examined in the simulation study. The proposed Cox-weighted method is applied to a competing risks dataset from a Hodgkin's disease study.  相似文献   
934.
基于可信性理论,本文给出了不允许缺货的经济生产量(EPQ)问题的期望值模型;研究了当单位生产准备费、单位储存费均为模糊变量且相互独立的情况下EPQ 问题的最佳期望单位存储费用、最佳期望单位生产批量及最佳期望生产周期,并得出了一些重要的结论;特殊情况下,讨论了当模型中的模糊参数分别为三角模糊变量、梯形模糊变量及正态模糊变量情况下的EPQ 问题的最优存储策略;最后,针对上述三种情况本文分别给出了一些数值例子验证了模型的有效性和合理性;本文所得到的结果为求解EPQ 问题设计算法提供了理论依据.  相似文献   
935.
文章从理论阐述、译例选取两方面突出了范·路文兹瓦特(Kitty Van Leuven—Zwart)的比较模式在翻译转换中的理论意义和实用价值,结合东西方不同翻译理论流派的观点,从其可操作性和理论根源上剖析了比较模式的合理性、科学性以及存在的缺陷。  相似文献   
936.
高速公路上的交通堵塞造成了道路利用效率低下,并伴随着能源消耗和环境污染问题,因此各种各样的高速公路控制方法应用于缓解交通堵塞。本文提出强化学习型匝道控制模型,该模型以交通流模拟为预测工具,以人工智能的强化学习为最优化选择模型,并具有一定的自主性、有记忆功能和性能反馈功能,且是一种动态的过程。应用JAVA针对不同的交通状态进行模拟再现,模拟结果表明匝道控制模型对于减少交通堵塞具有显著的效果。  相似文献   
937.
Abstract

Purpose: To examine differences in site of death and costs of services by primary diagnosis for patients receiving home-based palliative care as compared to usual care at the end of life verity of illness, service use, and site of death.

Design and Methods: A nonequivalent group design was employed with 298 terminally ill patients diagnosed with cancer, CHF, or COPD enrolled. The treatment group received an interdisciplinary home-based palliative care program and the comparison group received usual Kaiser Permanente services. Data collected included patient demographics, se-

Results: Among all diseases, patients enrolled in palliative care were more likely to die at home. Enrollment in palliative care was significant associated with cost reductions for patients with cancer, COPD, and CHF. No significant difference was found between diagnostic groups in terms of magnitude of cost savings.

Implications: Provision of interdisciplinary home-based palliative care at end of life can effectively increase the likelihood of dying at home for patients with CHF, COPD, and cancer while realizing significant COSt savings.  相似文献   
938.
随着动漫产业的高速发展,其人才的培养也越来越受到业界和相关部门的高度重视。高校作为培养动漫人才的重要基地,是发展动漫产业与培养动漫人才的孵化器,文章针对高校培养动漫人才教育问题进行了讨论,并提出了若干对策建议。  相似文献   
939.
For the linear-exponential distribution with increasing hazard rate, exact and explicit expressions for means, product moments and percentage points of order statistics are obtained. Some recurrence relations for both single and product moments of order statistics are also derived. These recurrence relations would enable one to obtain all the higher order moments of order statistics for all sample sizes from those of the lower order  相似文献   
940.
This article analyses the processes of deviation from the Bismarckian welfare model in Italy, with a focus on social assistance. The sector was reformed in 2000, with new service provision functions being assigned to local institutions and the affirmation of a universalistic principle of access. However, an analysis of social expenditure data and a review of the process of implementation of the reform demonstrate that many local governments have been unable to enact the innovation and that a homogeneous nationwide trend of deviation from the Bismarckian tradition is absent. This absence is explained by looking both at the local institutional arrangements that have historically characterized the different Italian territories and at the present relationships among national, regional, and local governments.  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