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81.
高新技术的成长发育离不开风险投资以及政府、市场的引导 ,离不开基础研究与人力资源的开发 ,更需要引进大量的资金及国外的先进技术 ,同时其发展也与传统产业的提升有着密不可分的关系 ,因此发展高新技术产业应在妥善处理好这些关系上下功夫  相似文献   
82.
在硫酸铁铵的催化下 ,利用高压微波技术 ,快速合成了肉桂酸甲酯。最佳反应条件为 :甲醇和肉桂酸的摩尔比为 5 :1,催化剂用量为 2 .0g ,微波时间为 3min ,微波功率为 72 9W ,产率达93.8%。  相似文献   
83.
高校高新技术产业是我国高新技术产业的重要组成部分。发展高新技术产业 ,既是高校的优势 ,也是高校的历史责任。引入风险投资、发行股票并争取上市、进入以大学为主体的高科技园 ,是高校大力发展高新技术产业的必由之路  相似文献   
84.
亨利·詹姆斯是美国著名的小说家。他一生关心的是人与人之间的关系。在他横贯两大陆的特殊生活中 ,他发现欧洲代表一种文明 ,美国则代表另一种文明。美国人有很强的道德意识 ,尚未被虚伪诡诈、势利庸俗的世风所玷污 ,但他们诚实的背后却隐藏着无知 ;欧洲有灿烂的文化 ,所以 ,欧洲人有教养 ,有品味 ,但他们却道貌岸然 ,内心充满门第等级、虚荣傲慢等传统偏见。通过新旧两大陆文明的对比 ,詹姆斯试图发现并阐释一种新的文明社会 ,使人类能在更高层面上和谐相处。他对此理想文明社会的探索及追求贯穿于他的主要作品及他的一生。  相似文献   
85.
Summary The paper deals with missing data and forecasting problems in multivariate time series making use of the Common Components Dynamic Linear Model (DLMCC), presented in Quintana (1985), and West and Harrison (1989). Some results are presented and discussed: exploiting the correlation between series, estimated by the DLMCC, the paper shows as it is possible to update state vector posterior distributions for the unobserved series. This is realized on the base of the updating of the observed series state vectors, for which the usual Kalman filter equations can be applied. An application concerning some Italian private consumption series provides an example of the model capabilities.  相似文献   
86.
Occupational segregation by sex remains the most pervasive aspect of the labour market. In the past, most research on this topic has concentrated on explanations of women’s segregation into low paid and low status occupations, or investigations of women who have crossed gender boundaries into men’s jobs, and the potential impact on them and the occupations. In contrast, this article reports on a small‐scale, qualitative study of ten men who have crossed into what are generally defined as ‘women’s jobs’. In doing so, one of the impacts on them has been that they have experienced challenges to their masculine identity from various sources and in a variety of ways. The men’s reactions to these challenges, and their strategies for developing and accommodating their masculinity in light of these challenges, are illuminating. They either attempted to maintain a traditional masculinity by distancing themselves from female colleagues, and/or partially (re)constructed a different masculinity by identifying with their non‐traditional occupations. This they did as often as they deemed necessary as a response to different forms of challenge to their gender identities from both men and women. Finally, the article argues that these responses work to maintain the men as the dominant gender, even in these traditionally defined ‘women’s jobs’.  相似文献   
87.
采用常规低压集成电路工艺实现了耐压达1000V的高压横向MOSFET,详细介绍了该高压横向MOSFET的设计方法、器件结构、工艺技术及测试结果。文中从实验和分析的角度上首次探讨了覆盖在漂移区上面的金属栅长度对该高压横向MOSFT击穿电压的影响。  相似文献   
88.
Annual concentrations of toxic air contaminants are of primary concern from the perspective of chronic human exposure assessment and risk analysis. Despite recent advances in air quality monitoring technology, resource and technical constraints often impose limitations on the availability of a sufficient number of ambient concentration measurements for performing environmental risk analysis. Therefore, sample size limitations, representativeness of data, and uncertainties in the estimated annual mean concentration must be examined before performing quantitative risk analysis. In this paper, we discuss several factors that need to be considered in designing field-sampling programs for toxic air contaminants and in verifying compliance with environmental regulations. Specifically, we examine the behavior of SO2, TSP, and CO data as surrogates for toxic air contaminants and as examples of point source, area source, and line source-dominated pollutants, respectively, from the standpoint of sampling design. We demonstrate the use of bootstrap resampling method and normal theory in estimating the annual mean concentration and its 95% confidence bounds from limited sampling data, and illustrate the application of operating characteristic (OC) curves to determine optimum sample size and other sampling strategies. We also outline a statistical procedure, based on a one-sided t-test, that utilizes the sampled concentration data for evaluating whether a sampling site is compliance with relevant ambient guideline concentrations for toxic air contaminants.  相似文献   
89.
The authors consider the optimal design of sampling schedules for binary sequence data. They propose an approach which allows a variety of goals to be reflected in the utility function by including deterministic sampling cost, a term related to prediction, and if relevant, a term related to learning about a treatment effect To this end, they use a nonparametric probability model relying on a minimal number of assumptions. They show how their assumption of partial exchangeability for the binary sequence of data allows the sampling distribution to be written as a mixture of homogeneous Markov chains of order k. The implementation follows the approach of Quintana & Müller (2004), which uses a Dirichlet process prior for the mixture.  相似文献   
90.
To protect public-use microdata, one approach is not to allow users access to the microdata. Instead, users submit analyses to a remote computer that reports back basic output from the fitted model, such as coefficients and standard errors. To be most useful, this remote server also should provide some way for users to check the fit of their models, without disclosing actual data values. This paper discusses regression diagnostics for remote servers. The proposal is to release synthetic diagnostics—i.e. simulated values of residuals and dependent and independent variables–constructed to mimic the relationships among the real-data residuals and independent variables. Using simulations, it is shown that the proposed synthetic diagnostics can reveal model inadequacies without substantial increase in the risk of disclosures. This approach also can be used to develop remote server diagnostics for generalized linear models.  相似文献   
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