全文获取类型
收费全文 | 1683篇 |
免费 | 62篇 |
专业分类
管理学 | 181篇 |
民族学 | 14篇 |
人口学 | 149篇 |
丛书文集 | 13篇 |
理论方法论 | 217篇 |
综合类 | 11篇 |
社会学 | 997篇 |
统计学 | 163篇 |
出版年
2023年 | 18篇 |
2022年 | 13篇 |
2021年 | 14篇 |
2020年 | 29篇 |
2019年 | 30篇 |
2018年 | 44篇 |
2017年 | 82篇 |
2016年 | 56篇 |
2015年 | 38篇 |
2014年 | 50篇 |
2013年 | 273篇 |
2012年 | 71篇 |
2011年 | 73篇 |
2010年 | 52篇 |
2009年 | 44篇 |
2008年 | 61篇 |
2007年 | 60篇 |
2006年 | 74篇 |
2005年 | 54篇 |
2004年 | 62篇 |
2003年 | 51篇 |
2002年 | 44篇 |
2001年 | 32篇 |
2000年 | 29篇 |
1999年 | 27篇 |
1998年 | 25篇 |
1997年 | 27篇 |
1996年 | 18篇 |
1995年 | 18篇 |
1994年 | 20篇 |
1993年 | 12篇 |
1992年 | 13篇 |
1991年 | 18篇 |
1990年 | 10篇 |
1989年 | 19篇 |
1988年 | 16篇 |
1987年 | 16篇 |
1986年 | 12篇 |
1985年 | 13篇 |
1984年 | 14篇 |
1983年 | 19篇 |
1982年 | 12篇 |
1981年 | 10篇 |
1980年 | 11篇 |
1979年 | 9篇 |
1977年 | 6篇 |
1976年 | 5篇 |
1975年 | 6篇 |
1974年 | 7篇 |
1970年 | 7篇 |
排序方式: 共有1745条查询结果,搜索用时 31 毫秒
91.
Urban Ecosystems - Urbanization may negatively affect forest obligate bat species. We compared the roosting behavior of federally endangered Indiana bats (Myotis sodalis) in a fragmented site,... 相似文献
92.
93.
Nicole Gravina Jamie Villacorta Kristin Albert Ronald Clark Scott Curry David Wilder 《Journal of Organizational Behavior Management》2018,38(2-3):191-224
We reviewed the Journal of Applied Behavior Analysis (JABA), Journal of Organizational Behavior Management (JOBM), and Behavior Analysis in Practice (BAP) from 1990 to 2016, to identify articles that evaluated organizational behavior management interventions in a human service setting. Of those articles, 75 articles met the inclusion criteria for the review, 44 from JABA (1990 to 2016), 22 from JOBM (1990 to 2016), and 7 from BAP (2008 to 2016). We categorized each selected article by setting, employee population, client population, assessment, dependent variable, independent variable, and outcome measures. Results from the review are discussed for all three journals. Recommendations are made to broaden the scope of population and dependent variable targets, include more assessments, and include outcome data when applicable. 相似文献
94.
Reuven Cohen Mira Gonen Asaf Levin Shmuel Onn 《Journal of Combinatorial Optimization》2017,33(2):645-659
In this paper we define the exact k-coverage problem, and study it for the special cases of intervals and circular-arcs. Given a set system consisting of a ground set of n points with integer demands \(\{d_0,\dots ,d_{n-1}\}\) and integer rewards, subsets of points, and an integer k, select up to k subsets such that the sum of rewards of the covered points is maximized, where point i is covered if exactly \(d_i\) subsets containing it are selected. Here we study this problem and some related optimization problems. We prove that the exact k-coverage problem with unbounded demands is NP-hard even for intervals on the real line and unit rewards. Our NP-hardness proof uses instances where some of the natural parameters of the problem are unbounded (each of these parameters is linear in the number of points). We show that this property is essential, as if we restrict (at least) one of these parameters to be a constant, then the problem is polynomial time solvable. Our polynomial time algorithms are given for various generalizations of the problem (in the setting where one of the parameters is a constant). 相似文献
95.
Mahyar Eftekhar Hongmin Li Luk N. Van Wassenhove Scott Webster 《Production and Operations Management》2017,26(5):802-816
Despite high demand and resource limitations, humanitarian organizations (HOs) typically do not share resources and/or coordinate in the field. While coordination enhances operational performance and saves costs, the general perception is that it dilutes the media attention that individual organizations might receive, and negatively influences their future donation income. In this study, we empirically unveil the impact of media exposure and operational performance on the donations obtained by HOs. Then, based on the empirical results, we develop a stylized model to characterize the structure of preferred coordination policies with respect to an organization's funding source and main mandate. Our findings shed light on the incentives and dynamics that drive behaviors in humanitarian operations and provide insights for policy makers on designing and implementing mechanisms that encourage humanitarian coordination. 相似文献
96.
Risk Estimation and Value-of-Information Analysis for Three Proposed Genetic Screening Programs for Chronic Beryllium Disease Prevention 总被引:1,自引:0,他引:1
Scott M. Bartell Rafael A. Ponce Timothy K. Takaro Richard O. Zerbe Gilbert S. Omenn & Elaine M. Faustman 《Risk analysis》2000,20(1):87-100
Genetic differences (polymorphisms) among members of a population are thought to influence susceptibility to various environmental exposures. In practice, however, this information is rarely incorporated into quantitative risk assessment and risk management. We describe an analytic framework for predicting the risk reduction and value-of-information (VOI) resulting from specific risk management applications of genetic biomarkers, and we apply the framework to the example of occupational chronic beryllium disease (CBD), an immune-mediated pulmonary granulomatous disease. One described Human Leukocyte Antigen gene variant, HLA-DP beta 1*0201, contains a substitution of glutamate for lysine at position 69 that appears to have high sensitivity (approximately 94%) but low specificity (approximately 70%) with respect to CBD among individuals occupationally exposed to respirable beryllium. The expected postintervention CBD prevalence rates for using the genetic variant (1) as a required job placement screen, (2) as a medical screen for semiannual in place of annual lymphocyte proliferation testing, or (3) as a voluntary job placement screen are 0.08%, 0.8%, and 0.6%, respectively, in a hypothetical cohort with 1% baseline CBD prevalence. VOI analysis is used to examine the reduction in total social cost, calculated as the net value of disease reduction and financial expenditures, expected for proposed CBD intervention programs based on the genetic susceptibility test. For the example cohort, the expected net VOI per beryllium worker for genetically based testing and intervention is $13,000, $1,800, and $5,100, respectively, based on a health valuation of $1.45 million per CBD case avoided. VOI results for alternative CBD evaluations are also presented. Despite large parameter uncertainty, probabilistic analysis predicts generally positive utility for each of the three evaluated programs when avoidance of a CBD case is valued at $1 million or higher. Although the utility of a proposed risk management program may be evaluated solely in terms of risk reduction and financial costs, decisions about genetic testing and program implementation must also consider serious social, legal, and ethical factors. 相似文献
97.
Application of Executive Order 12898 to risk assessment of highway or rail transport of hazardous materials has proven difficult; in general, the location and conditions affecting the propagation of a plume of hazardous material released in a potential accident are unknown. Therefore, analyses have only been possible in a geographically broad or approximate manner. The advent of geographic information systems and development of software enhancements at Sandia National Laboratories have made kilometer-by-kilometer analysis of populations tallied by U.S. Census blocks along entire routes practicable. Tabulations of total or racially/ethnically distinct populations close to a route, its alternatives, or the broader surrounding area, can then be compared and differences evaluated statistically. This article presents methods of comparing populations and their racial/ethnic compositions using simple tabulations, histograms, and chi-square tests for statistical significance of differences found. Two examples of these methods are presented: comparison of two routes and comparison of a route with its surroundings. 相似文献
98.
99.
Ian Scott 《Public Organization Review》2003,3(3):247-267
Twenty-five years ago, the Hong Kong government was lauded as the model of a small, restricted government which was most suited to capitalist economic growth. Since that time, the government and the organizations which it has created have expanded to such an extent that there has been widespread concern that the public sector has grown too large. This article examines the reasons for the rapid growth in the size of the public sector, reflects on the organizational forms outside the traditional civil service that have been adopted, and analyzes the attempts that have been made to reduce the public bureaucracy by corporatizing and privatizing some of the services that it provides. Central to the argument presented is the question of whether an ideological commitment to small government or other functional and political factors have been the critical determinants of organizational change. 相似文献
100.
A sample size justification should be given for all clinical investigations. However, sometimes the objective of a trial is to estimate an effect with a view to planning a later definitive study. This paper describes the calculations for designing studies where one wishes to adopt an estimation approach through using confidence intervals around the overall response. Calculations are given for data anticipated to take a Normal form. Copyright © 2004 John Wiley & Sons, Ltd. 相似文献