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   3285篇
  免费   100篇
  国内免费   1篇
管理学   511篇
民族学   16篇
人才学   1篇
人口学   269篇
丛书文集   30篇
理论方法论   347篇
综合类   23篇
社会学   1783篇
统计学   406篇
  2023年   20篇
  2022年   12篇
  2021年   16篇
  2020年   43篇
  2019年   63篇
  2018年   74篇
  2017年   88篇
  2016年   86篇
  2015年   57篇
  2014年   75篇
  2013年   549篇
  2012年   102篇
  2011年   92篇
  2010年   84篇
  2009年   89篇
  2008年   101篇
  2007年   105篇
  2006年   104篇
  2005年   109篇
  2004年   104篇
  2003年   104篇
  2002年   112篇
  2001年   63篇
  2000年   57篇
  1999年   66篇
  1998年   55篇
  1997年   66篇
  1996年   70篇
  1995年   42篇
  1994年   47篇
  1993年   47篇
  1992年   45篇
  1991年   49篇
  1990年   46篇
  1989年   38篇
  1988年   35篇
  1987年   33篇
  1986年   21篇
  1985年   25篇
  1984年   42篇
  1983年   39篇
  1982年   35篇
  1981年   47篇
  1980年   31篇
  1979年   24篇
  1978年   23篇
  1977年   30篇
  1976年   29篇
  1975年   18篇
  1973年   22篇
排序方式: 共有3386条查询结果,搜索用时 328 毫秒
31.
Abstract Over the 1980–1990 period, employment in producer services industries in the nonmetropolitan United States increased substantially. This growth resulted in the development of nonmetropolitan growth nodes in producer services industries. A growth node refers to a nonmetropolitan area that contains a greater than average concentration of employment in a particular industry sector relative to other nonmetropolitan areas. Moreover, this industry concentration not only increases over time, but also represents an important source of employment growth within the area. With nonmetropolitan counties as the spatial unit of analysis, 317 growth nodes in producer services industries are identified for the 1980–1990 period. Access to workers with clerical and administrative support skills, access to highly educated workers, higher earnings per employed worker, access to recreational amenities, and proximity to metropolitan areas were associated with the development of nonmetropolitan growth nodes in producer services industries during this period.  相似文献   
32.
33.
Summary.  The system for monitoring suicides in Hong Kong has considerable delays in reporting as the cause of death needs to be determined by a coroner's investigation. However, timely estimates of suicide rates are desirable to assist in the formulation of public health policies. This motivated us to develop a non-parametric procedure to estimate the intensity function of a Poisson process in the presence of reporting delays. We give closed form estimators of the Poisson intensity and the delay distribution, conduct simulation studies to evaluate the method proposed and derive their asymptotic properties. The method proposed is applied to estimate the intensity of suicide in Hong Kong.  相似文献   
34.
In conjunction with TIMET at Waunarlwydd (Swansea, UK) a model has been developed that will optimise the scheduling of various blooms to their eight furnaces so as to minimise the time taken to roll these blooms into the finished mill products. This production scheduling model requires reliable data on times taken for the various furnaces that heat the slabs and blooms to reach the temperatures required for rolling. These times to temperature are stochastic in nature and this paper identifies the distributional form for these times using the generalised F distribution as a modelling framework. The times to temperature were found to be similarly distributed over all furnaces. The identified distributional forms were incorporated into the scheduling model to optimise a particular campaign that was run at TIMET Swansea. Amongst other conclusion it was found that, compared to the actual campaign, the model produced a schedule that reduced the makespan by some 35%.  相似文献   
35.
There are many models that require the estimation of a set of ordered parameters. For example, multivariate analysis of variance often is formulated as testing for the equality of the parameters versus an ordered alternative. This problem, referred to as isotonic inference, constrained inference, or isotonic regression, has led to the development of general solutions, not often easy to apply in special models. In this expository paper, we study the special case of a separable convex quadratic programming problem for which the optimality conditions lead to a readily solved linear complementarity problem in the Lagrange multipliers, and subsequently to an equivalent linear programming problem, whose solution can be used to recover the solution of the original isotonic problem. The method can be applied to estimating ordered correlations, ordered binomial probabilities, ordered Poisson parameters, ordered exponential scale parameters, or ordered risk differences.  相似文献   
36.
Parental choice of school is one of the main platforms of government education policy and is the centre piece of the Parents Charter. But sociological understanding of choice and choice-making is woefully underdeveloped. This paper draws on an ESRC study of market forces in education to explore social class variations in choice of school in one specific locality. The complexity of choice-making is portrayed using data from interviews with parents and it is argued that middle-class parents are taking full advantage of ‘the market’ to sustain or re-assert their class advantages.  相似文献   
37.
38.
39.
40.
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