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   16310篇
  免费   335篇
  国内免费   16篇
管理学   2070篇
民族学   98篇
人才学   2篇
人口学   1407篇
丛书文集   168篇
理论方法论   1551篇
综合类   720篇
社会学   8606篇
统计学   2039篇
  2023年   95篇
  2021年   121篇
  2020年   248篇
  2019年   321篇
  2018年   405篇
  2017年   570篇
  2016年   412篇
  2015年   322篇
  2014年   389篇
  2013年   2553篇
  2012年   583篇
  2011年   554篇
  2010年   463篇
  2009年   409篇
  2008年   494篇
  2007年   506篇
  2006年   511篇
  2005年   459篇
  2004年   379篇
  2003年   348篇
  2002年   374篇
  2001年   396篇
  2000年   329篇
  1999年   334篇
  1998年   247篇
  1997年   228篇
  1996年   223篇
  1995年   207篇
  1994年   202篇
  1993年   209篇
  1992年   226篇
  1991年   230篇
  1990年   224篇
  1989年   195篇
  1988年   197篇
  1987年   220篇
  1986年   167篇
  1985年   178篇
  1984年   213篇
  1983年   186篇
  1982年   183篇
  1981年   163篇
  1980年   140篇
  1979年   144篇
  1978年   114篇
  1977年   108篇
  1976年   116篇
  1975年   124篇
  1974年   95篇
  1973年   79篇
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
991.
Disasters garner attention when they occur, and organizations commonly extract valuable lessons from visible failures, adopting new behaviors in response. For example, the United States saw numerous security policy changes following the September 11 terrorist attacks and emergency management and shelter policy changes following Hurricane Katrina. But what about those events that occur that fall short of disaster? Research that examines prior hazard experience shows that this experience can be a mixed blessing. Prior experience can stimulate protective measures, but sometimes prior experience can deceive people into feeling an unwarranted sense of safety. This research focuses on how people interpret near‐miss experiences. We demonstrate that when near‐misses are interpreted as disasters that did not occur and thus provide the perception that the system is resilient to the hazard, people illegitimately underestimate the danger of subsequent hazardous situations and make riskier decisions. On the other hand, if near‐misses can be recognized and interpreted as disasters that almost happened and thus provide the perception that the system is vulnerable to the hazard, this will counter the basic “near‐miss” effect and encourage mitigation. In this article, we use these distinctions between resilient and vulnerable near‐misses to examine how people come to define an event as either a resilient or vulnerable near‐miss, as well as how this interpretation influences their perceptions of risk and their future preparedness behavior. Our contribution is in highlighting the critical role that people's interpretation of the prior experience has on their subsequent behavior and in measuring what shapes this interpretation.  相似文献   
992.
Companies are now investing in the new technologies of the 1990s. This article deals with the central question of why and how companies work together on technological innovation. First the author looks at the reality of technological innovation, and review reasons why companies might want to work together in this area. They then uncover the different types of collaboration involved in technological innovation. These forms are innovation networks, and they identify several success factors for innovation networks.  相似文献   
993.
994.
Network Evening News Coverage of Environmental Risk   总被引:2,自引:0,他引:2  
ABC, CBS, and NBC's carefully crafted and expensively produced evening news broadcasts devoted 1.7% of their air time to 564 stories about man-made environmental risks during the period from January 1984 to February 1986. Little relationship was found between amount of coverage and public health risk. Instead, the networks appeared to be using traditional journalistic determinants of news (timeliness, proximity, prominence, consequence, and human interest) plus the broadcast criterion of visual impact to determine the degree of coverage of risk issues. Government, industry, and citizens accounted for two-thirds of the sources cited by the networks. Experts and spokespersons for environmental advocacy groups were sparsely used as sources. Given the media's need for news pegs, acute and chronic risk stories were covered differently. Acute risk stories were reported in a clearly defined cycle, peaking on the second day with on-the-scene reports and film-clips of devastation. In keeping with a decrease in visual drama, later reports were shorter and emphasized legal and political considerations. Chronic risk coverage followed the release of new scientific, legal, or political information.  相似文献   
995.
This article describes how a risk-return portfolio analysis, as originally developed in economics and finance, can be applied to product-line decisions. This approach uses direct estimates of return, and explicitly considers risk, or variation in return; most of the product portfolio models in use today forecast return by correlation, and lack explicit treatment of risk. The approach provides guidance for new product development activities as well as for allocating resources among a corporation's existing product lines. The article explains how organizations can apply this approach to their own product portfolio decisions, and includes a detailed example of how one company used this model.  相似文献   
996.
This article discusses a longitudinal study of firms selected for their expertise in environmental analysis. It is primarily designed to test two general propositions. The first, that environmental analysis is increasing in importance over time— both within and between firms; and the second, that environmental analysis is most viable as a separate, freestanding function within the organization.  相似文献   
997.
The Color Additives Scientific Review Panel considered whether there was information sufficient to perform a carcinogenic risk assessment on the colors D&C Red No. 19 (R-19), D&C Red No. 37 (R-37), D&C Orange No. 17 (O-17), D&C Red No. 9 (R-9), D&C Red No. 8 (R-8) and FD&C Red No. 3 (R-3) and to evaluate the assessments sent to FDA as part of the petitions for use of the colors for drug and external uses by the Cosmetic, Toiletry and Fragrance Association (CTFA). There is a lack of human data concerning the colors for making a human health assessment, so the assessments are based upon the extrapolation of animal data. The risk assessments are determined for exposure to single chemicals. Excluded from consideration are possible effects from exposure to multiple chemicals, such as co-carcinogenesis, promotion, synergism, antagonism, etc. In the light of recent efforts in establishing a consensus in risk assessment, the Panel has determined that the CTFA assessments for R-10, O-17, and R-9 are consistent with present acceptable usages, although it questions some of the assumptions used in the assessments. The Panel identified a number of general assumptions made, and discusses their validity, their impact on total uncertainty, and the potential options to address the gaps in understanding that necessitate the assumption. The Panel also derived revised risk estimates using more "reasonable" assumptions than "worst-case" situations, for 90th percentile and average exposure. For those assumptions that are easily quantifiable, the Panel's estimates are less than an order of magnitude lower than the CTFA risk estimates, indicating that the underestimates and overestimates of the CTFA risk estimates tend to balance each other. The impact of most of the assumptions is not quantifiable. The assessment for R-3 is complicated by the fact that there is no good skin penetrance study for this color. It was assumed that the penetrance is similar to that of another water-soluble xanthene color, R-19. It is expected that the absorption of the color is not likely to exceed that of the smaller molecule, R-19. Therefore, the risk estimates are similar to the CTFA estimates, but with different reasoning. The estimates for R-8 and R-37 are different from the others in that there is a lack of any exposure or toxicological information on these colors.(ABSTRACT TRUNCATED AT 400 WORDS)  相似文献   
998.
Studies often note the wide differences that exist in costs per death avoided across U.S. federal programs and regulatory contexts. This paper explores two new, related explanations for these differences. First, it argues that the patterns of revealed preferences (public allocations) may be related to public values, which are measured here through subjects' expressed preference responses to a contingent valuation survey regarding risk reduction. Subjects' expressed values are compared to actual (and proposed) costs of safety regulations for a similar set of hazards. We discover strong congruence in the ranking of expressed values and actual values. Second, the paper presents the results of a subsequent survey that investigates why the patterns observed in the first survey might occur. It suggests that one reason for the observed similarities between revealed and expressed preferences may be in how choices are framed. The paper hypothesizes that both subjects and decision makers may frame valuation decisions in the same way: as percentage changes from the reference point provided by the base rate of deaths for that hazard.  相似文献   
999.
Quantitative Approaches in Use to Assess Cancer Risk   总被引:4,自引:0,他引:4  
  相似文献   
1000.
This paper surveys the application of U.K. monopoly policy and examines its general impact on industrial structure and market processes. It considers the effects of the Competition Act 1980 in relation to U.K. monopoly control and concludes that unless further measures are introduced, competitive pressures are likely to be weakened over the longer term.  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