全文获取类型
收费全文 | 12235篇 |
免费 | 342篇 |
专业分类
管理学 | 1529篇 |
民族学 | 52篇 |
人才学 | 1篇 |
人口学 | 1000篇 |
丛书文集 | 69篇 |
教育普及 | 3篇 |
理论方法论 | 1133篇 |
综合类 | 127篇 |
社会学 | 6553篇 |
统计学 | 2110篇 |
出版年
2023年 | 58篇 |
2021年 | 66篇 |
2020年 | 157篇 |
2019年 | 236篇 |
2018年 | 255篇 |
2017年 | 375篇 |
2016年 | 274篇 |
2015年 | 208篇 |
2014年 | 287篇 |
2013年 | 2478篇 |
2012年 | 350篇 |
2011年 | 340篇 |
2010年 | 255篇 |
2009年 | 233篇 |
2008年 | 259篇 |
2007年 | 251篇 |
2006年 | 283篇 |
2005年 | 253篇 |
2004年 | 215篇 |
2003年 | 191篇 |
2002年 | 205篇 |
2001年 | 288篇 |
2000年 | 268篇 |
1999年 | 278篇 |
1998年 | 182篇 |
1997年 | 164篇 |
1996年 | 224篇 |
1995年 | 217篇 |
1994年 | 220篇 |
1993年 | 228篇 |
1992年 | 240篇 |
1991年 | 222篇 |
1990年 | 243篇 |
1989年 | 216篇 |
1988年 | 201篇 |
1987年 | 181篇 |
1986年 | 168篇 |
1985年 | 178篇 |
1984年 | 180篇 |
1983年 | 132篇 |
1982年 | 129篇 |
1981年 | 109篇 |
1980年 | 119篇 |
1979年 | 118篇 |
1978年 | 102篇 |
1977年 | 86篇 |
1976年 | 83篇 |
1975年 | 86篇 |
1974年 | 59篇 |
1973年 | 54篇 |
排序方式: 共有10000条查询结果,搜索用时 796 毫秒
81.
Allison Zippay Ph.D. Anu Rangarajan Ph.D. 《Child and Adolescent Social Work Journal》2007,24(2):153-172
This article reports the results of a study that examined the ways in which current and recent TANF recipients assembled or
“packaged” their child care arrangements among formal and informal providers. The findings are drawn from in-person, in-depth
interviews with current and former welfare recipients. The study found that most of the respondents used multiple providers
within the category of informal child care for reasons including availability, the use of a network of social acquaintances as a
problem-solving resource, the need to accommodate irregular work hours, and personal trauma that contributed to a distrust
of strangers in formal settings. The findings can affect the efficacy of practice with TANF recipients by contributing to
social workers’ understanding of the context of decision-making regarding child care. 相似文献
82.
FINNEY DJ 《Journal of the American Statistical Association》1948,43(244):566-571
83.
This paper presents an improved efficiency measurement tool by modifying the existing data envelopment analysis methodology to permit the incorporation of expert knowledge. A previous paper examined the inclusion of such knowledge within the additive model. This information appeared in the form of a binary classification of a subset of the decision making units under study (e.g. good versus poor performers). In the current paper, we extend this logic to the input-oriented radial projection model. We demonstrate that the inclusion of this and other forms of expert judgment can improve the performance of the DEA tool in the sense that the efficiency scores are more in line with expert/management beliefs. 相似文献
84.
The probability of illness caused by very low doses of pathogens cannot generally be tested due to the numbers of subjects that would be needed, though such assessments of illness dose response are needed to evaluate drinking water standards. A predictive Bayesian dose-response assessment method was proposed previously to assess the unconditional probability of illness from available information and avoid the inconsistencies of confidence-based approaches. However, the method uses knowledge of the conditional dose-response form, and this form is not well established for the illness endpoint. A conditional parametric dose-response function for gastroenteric illness is proposed here based on simple numerical models of self-organized host-pathogen systems and probabilistic arguments. In the models, illnesses terminate when the host evolves by processes of natural selection to a self-organized critical value of wellness. A generalized beta-Poisson illness dose-response form emerges for the population as a whole. Use of this form is demonstrated in a predictive Bayesian dose-response assessment for cryptosporidiosis. Results suggest that a maximum allowable dose of 5.0 x 10(-7) oocysts/exposure (e.g., 2.5 x 10(-7) oocysts/L water) would correspond with the original goals of the U.S. Environmental Protection Agency Surface Water Treatment Rule, considering only primary illnesses resulting from Poisson-distributed pathogen counts. This estimate should be revised to account for non-Poisson distributions of Cryptosporidium parvum in drinking water and total response, considering secondary illness propagation in the population. 相似文献
85.
C. A. Glasbey D. J. Allcroft 《Journal of the Royal Statistical Society. Series C, Applied statistics》2008,57(3):343-355
Summary. To investigate the variability in energy output from a network of photovoltaic cells, solar radiation was recorded at 10 sites every 10 min in the Pentland Hills to the south of Edinburgh. We identify spatiotemporal auto-regressive moving average models as the most appropriate to address this problem. Although previously considered computationally prohibitive to work with, we show that by approximating using toroidal space and fitting by matching auto-correlations, calculations can be substantially reduced. We find that a first-order spatiotemporal auto-regressive (STAR(1)) process with a first-order neighbourhood structure and a Matern noise process provide an adequate fit to the data, and we demonstrate its use in simulating realizations of energy output. 相似文献
86.
The ability to infer parameters of gene regulatory networks is emerging as a key problem in systems biology. The biochemical
data are intrinsically stochastic and tend to be observed by means of discrete-time sampling systems, which are often limited
in their completeness. In this paper we explore how to make Bayesian inference for the kinetic rate constants of regulatory
networks, using the stochastic kinetic Lotka-Volterra system as a model. This simple model describes behaviour typical of
many biochemical networks which exhibit auto-regulatory behaviour. Various MCMC algorithms are described and their performance
evaluated in several data-poor scenarios. An algorithm based on an approximating process is shown to be particularly efficient. 相似文献
87.
D. R. Cox 《Journal of the Royal Statistical Society. Series A, (Statistics in Society)》2003,166(2):241-246
Summary. Possible health hazards from mobile phones arise from the use of the phones themselves and via the base stations that relay signals. Except for an increase in traffic accidents induced by the use of mobile phones in cars the evidence for a health hazard is at most indirect, but it cannot be entirely dismissed; the phones have not been widely used for sufficiently long for direct epidemiological studies to have high sensitivity for detecting any induced incidence of cancer, for example. The background and evidence are briefly reviewed and the steps taken in the UK to make information widely available described. 相似文献
88.
The Alchian and Allen theorem predicts that it will be harder to find "good" apples in the State of Washington, a prime apple-growing region, than in, say, New York City, where the addition of shipping charges makes "bad" apples comparatively more expensive. We recast the theorem as a testable proposition by explicitly taking the supply side into account and identifying plausible scenarios in which a fixed cost either has no effect on the relative prices of high and low quality grades of the same good in distant markets or, indeed, causes more of the bad apples to be shipped out. 相似文献
89.
Drug treatment courts (DTCs), an alternative to traditional criminal courts, provide an innovative way to legally process some drug offenders. The origin and recent growth of the drug court system in the USA can be explained as an unintended consequence of a failing 'war on drugs'. In this article, we discuss the spread of adult DTCs throughout the USA, the main components of drug courts, controversies surrounding DTCs, and some criticisms of drug courts. We summarize the recent evaluations of adult DTCs, and highlight various DTC factors that have been found to reduce individual drug use and criminal activity. We also offer suggestions for future research on DTCs and conclude with policy recommendations. 相似文献
90.
1. Research shows that many emergency workers are affected physically and emotionally by critical incident stress. 2. Debriefings conducted by trained team members are an effective method to mitigate the impact of critical incident stress. A debriefing is a structured, time-limited group intervention. 3. Cooperation among community agencies is essential for the development and effective functioning of a critical incident stress debriefing team. 4. Several teams in Illinois have organized to form a Critical Incident Stress Debriefing Network. The Illinois network is part of an international organization composed of critical incident stress debriefing providers. 相似文献