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   128382篇
  免费   3536篇
  国内免费   1414篇
管理学   3589篇
劳动科学   26篇
民族学   1822篇
人才学   11篇
人口学   1781篇
丛书文集   16497篇
理论方法论   5340篇
综合类   91062篇
社会学   3984篇
统计学   9220篇
  2024年   211篇
  2023年   678篇
  2022年   1040篇
  2021年   1151篇
  2020年   1480篇
  2019年   1501篇
  2018年   1580篇
  2017年   1970篇
  2016年   1986篇
  2015年   2600篇
  2014年   6012篇
  2013年   8198篇
  2012年   7634篇
  2011年   8827篇
  2010年   7268篇
  2009年   7447篇
  2008年   7893篇
  2007年   9794篇
  2006年   9873篇
  2005年   9102篇
  2004年   8623篇
  2003年   8305篇
  2002年   6775篇
  2001年   5667篇
  2000年   3346篇
  1999年   1054篇
  1998年   530篇
  1997年   446篇
  1996年   373篇
  1995年   316篇
  1994年   238篇
  1993年   200篇
  1992年   164篇
  1991年   147篇
  1990年   83篇
  1989年   73篇
  1988年   75篇
  1987年   28篇
  1986年   30篇
  1985年   108篇
  1984年   107篇
  1983年   80篇
  1982年   69篇
  1981年   60篇
  1980年   51篇
  1979年   55篇
  1978年   48篇
  1977年   16篇
  1976年   11篇
  1975年   7篇
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
251.
镇海自五代始即已建县,在县治的一千余年中,她的地名曾数度更改,她的土地更是有沧海桑田之变化。近代以来随着社会历史的发展,镇海又有了天翻地覆的变化。如今,镇海县境虽析为宁波市治下的镇海区和北仑区,但这部新编的最后一部县志似可为镇海县千年历史的全面而真实的记载和总结。  相似文献   
252.
顾客第一论     
“顾客第一”有其特定的内涵,它充分体现社会主义企业的根本目的,因而是企业所有经营观念中的一个根本性观念,也是企业生产经营的一个根本指导思想。企业要实现其双重目的,促进物质文明和精神文明建设的发展,并树立各种现代经营观念,就必须坚持顾客第一。  相似文献   
253.
珠江三角洲文化形态的性质是务实求利;其特征是商业俗文化;其结构由岭南文化、中原文化、港澳文化和西方文化四因素构成;其地位是有中国特色的社会主义新文化的“曙光”,是中华民族大一统文化的“中介”。  相似文献   
254.
根据《中华人民共和国会计法》等法规条例,参照国际会计准则,高等学校的会计改革应当按基金会计原则,采用"资产=负债+基金结余"的会计平衡公式,实行预算会计模式的转换.  相似文献   
255.
This paper studies how an overall fuzzy preference relation can be constructed in the compensatory context of the simple additive difference model, when imprecision on the trade-offs has to be taken into account. Three credibility indices of preferences are analysed and illustrated by a numerical example. Arguments are presented supporting the use of the third index, for which an interesting transitivity property (which was an open problem) is proved.  相似文献   
256.
The World Health Organization (WHO) diagnostic criteria for diabetes mellitus were determined in part by evidence that in some populations the plasma glucose level 2 h after an oral glucose load is a mixture of two distinct distributions. We present a finite mixture model that allows the two component densities to be generalized linear models and the mixture probability to be a logistic regression model. The model allows us to estimate the prevalence of diabetes and sensitivity and specificity of the diagnostic criteria as a function of covariates and to estimate them in the absence of an external standard. Sensitivity is the probability that a test indicates disease conditionally on disease being present. Specificity is the probability that a test indicates no disease conditionally on no disease being present. We obtained maximum likelihood estimates via the EM algorithm and derived the standard errors from the information matrix and by the bootstrap. In the application to data from the diabetes in Egypt project a two-component mixture model fits well and the two components are interpreted as normal and diabetes. The means and variances are similar to results found in other populations. The minimum misclassification cutpoints decrease with age, are lower in urban areas and are higher in rural areas than the 200 mg dl-1 cutpoint recommended by the WHO. These differences are modest and our results generally support the WHO criterion. Our methods allow the direct inclusion of concomitant data whereas past analyses were based on partitioning the data.  相似文献   
257.
In electrical engineering, circuit designs are now often optimized via circuit simulation computer models. Typically, many response variables characterize the circuit's performance. Each response is a function of many input variables, including factors that can be set in the engineering design and noise factors representing manufacturing conditions. We describe a modelling approach which is appropriate for the simulator's deterministic input–output relationships. Non-linearities and interactions are identified without explicit assumptions about the functional form. These models lead to predictors to guide the reduction of the ranges of the designable factors in a sequence of experiments. Ultimately, the predictors are used to optimize the engineering design. We also show how a visualization of the fitted relationships facilitates an understanding of the engineering trade-offs between responses. The example used to demonstrate these methods, the design of a buffer circuit, has multiple targets for the responses, representing different trade-offs between the key performance measures.  相似文献   
258.
This paper provides an overview of retirement patterns in Hong Kong on the basis of limited data. A censored regression model is used to infer the retirement age from people‘s current retirement status and their current age. This model is equivalent to a restricted probit model, and the interpretation of parameters is straightforward. The results clearly show a negative income effect on the retirement decision. The retirement age seems to be positively related to lifetime earnings but negatively related to the rate of decline of earnings with age. JEL classification: C24, J14, J26 Received May 6, 1996 / Accepted February 5, 1997  相似文献   
259.
Economics of Radiation Protection: Equity Considerations   总被引:1,自引:1,他引:0  
In order to implement cost-benefit analysis of protective actions to reduce radiological exposures, one needs to attribute a monetary value to the avoided exposure. Recently, the International Commission on Radiological Protection has stressed the need to take into consideration not only the collective exposure to ionising radiation but also its dispersion in the population. In this paper, by using some well known and some recent results in the economics of uncertainty, we discuss how to integrate these recommendations in the valuation of the benefit of protection.  相似文献   
260.
Mosler  Karl 《Theory and Decision》1997,42(3):215-233
Indices and orderings are developed for evaluating alternative strategies in the management of risk. They reflect the goals of reducing individual and collective risks, of increasing equity, and of assigning priority to the reduction and to the equity of high risks. Individual risk is defined as the (random or non-random) level of exposure to a danger. In particular the role of a lower negligibility level is investigated. A class of indices is proposed which involves two parameters, a negligibility level and a parameter of inequality aversion, and several interpretations of the indices are discussed. We provide a set of eight axioms which are necessary and sufficient for this class of indices, and we present an approach to deal with partial information on the parameters.  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