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   11740篇
  免费   222篇
  国内免费   2篇
管理学   1592篇
民族学   72篇
人才学   3篇
人口学   1041篇
丛书文集   74篇
教育普及   1篇
理论方法论   1192篇
综合类   231篇
社会学   6066篇
统计学   1692篇
  2020年   167篇
  2019年   281篇
  2018年   290篇
  2017年   410篇
  2016年   294篇
  2015年   221篇
  2014年   287篇
  2013年   1904篇
  2012年   377篇
  2011年   376篇
  2010年   296篇
  2009年   283篇
  2008年   270篇
  2007年   321篇
  2006年   285篇
  2005年   291篇
  2004年   276篇
  2003年   198篇
  2002年   243篇
  2001年   299篇
  2000年   246篇
  1999年   230篇
  1998年   182篇
  1997年   171篇
  1996年   167篇
  1995年   156篇
  1994年   162篇
  1993年   166篇
  1992年   166篇
  1991年   164篇
  1990年   165篇
  1989年   158篇
  1988年   139篇
  1987年   161篇
  1986年   133篇
  1985年   156篇
  1984年   164篇
  1983年   147篇
  1982年   131篇
  1981年   98篇
  1980年   115篇
  1979年   123篇
  1978年   108篇
  1977年   90篇
  1976年   96篇
  1975年   105篇
  1974年   94篇
  1973年   74篇
  1972年   63篇
  1971年   55篇
排序方式: 共有10000条查询结果,搜索用时 0 毫秒
461.
This paper proposes a set of definitions for the concepts “validation” and “assessment” applied to expert systems (ESs). It develops a framework for this validation and demonstrates the framework on existing accounting and auditing ESs to elicit some of the research issues involved in ES validation. Validation is critical to the design and implementation of decision-making ESs. In a setting where objectivity is sought and variance is avoided, validation ascertains what a system knows, knows incorrectly, or does not know. Validation ascertains the system's level of expertise and investigates the theoretical basis on which the system is based. It evaluates the reliability of decisions made by the system. The validation framework developed in this paper is research methods. It is designed to reflect the unique aspects of ESs (in contrast to other types of computer programs) and can be used by ES developers as a basis from which to perform validation and by researchers as a framework to elicit research issues in validation.  相似文献   
462.
This note examines the sensitivity of the basic economic-order-quantity inventory model to lot-size errors when holding costs are assumed to be a strictly increasing (though not necessarily linear) function of average inventory. In particular, we show that the penalty associated with ordering either too much or too little is a function not only of the size of the error but of the shape of the holding-cost curve as well. We demonstrate that, under certain conditions, even relatively small lot-size errors can be extremely costly.  相似文献   
463.
This paper attempts to isolate and analyze the principal ideas of multiobjective optimization. We do this without casting aspersions on single-objective optimization or championing any one multiobjective technique. We examine each fundamental idea for strengths and weaknesses and subject two—efficiency and utility—to extended consideration. Some general recommendations are made in light of this analysis. Besides the simple advice to retain single-objective optimization as a possible approach, we suggest that three broad classes of multiobjective techniques are very promising in terms of reliably, and believably, achieving a most preferred solution. These are: (1) partial generation of the efficient set, a rubric we use to unify a wide spectrum of both interactive and analytic methods; (2) explicit utility maximization, a much-overlooked approach combining multiattribute decision theory and mathematical programming; and (3) interactive implicit utility maximization, the popular class of methods introduced by Geoffrion, Dyer, and Feinberg [24] and extended significantly by others.  相似文献   
464.
Social Science researchers have advanced important yet somewhat contradictory conclusions regarding the different economic and occupational reward structures faced by men and women. Income and wage differences between men and women have been shown to be sizable and persistent throughout the occupational hierarchy. Conversely, gender differences in occupational status, commonly scaled by the Duncan Socioeconomic Index, have been shown to be small or nonexistent in most studies. In an attempt to investigate this incongruity, the present study undertakes a comparison of the Duncan SEI and the Nam-Powers Occupational Status Scores in an empirical study of the occupational position of white men and women in 65 large standard metropolitan statistical areas (SMSAs) in 1970. While the findings of earlier studies showing no gender differences in occupational status are for the most part replicated using the Duncan SEI, use of the Nam-Powers scores prompts a much different conclusion. Large status differences between men and women are indicated using this latter scale, differences which are very much in line with income differences commonly cited. We suggest that the Nam-Powers metric should be used instead of the Duncan SEI in studies of occupational status of women and men.  相似文献   
465.
466.
This study was conducted in the southwest area of Brisbane, Australia, and is designed to explore and assess the health needs of Vietnamese migrant women. The needs of this group are becoming increasingly urgent due to ageing of the original immigrant refugee community and decreased capacity for support from their children and families. The study used a qualitative research strategy involving focus groups and in‐depth interviews with Vietnamese women between 18–65 years and interviews with Vietnamese health care providers. It shows that the women have had to deal with culture shock, low self‐esteem, lack of friends and relatives, unrecognized professional skills and most importantly in health terms, low socioeconomic status. Significant barriers to access health services and to improved health and well‐being were also identified, such as language difficulties, transportation, time, and knowledge about health education. Recognition of specific requirements of sub‐populations as well as broader socio‐economic and cultural determinants of health should be a guide to more effective planning and implementation of health promotion strategies. The changing needs, over time, of these sub‐populations should also be recognized.  相似文献   
467.
This study is based on repeated interviews with twelve heterosexual female commercial sex workers (SWs) in Perth. These informants deploy, with various degrees of success, strategies to demarcate ‘work-sex’, with its socially ascribed stigma, from ‘non-work sex’. Such strategies inhibit the spread of HIV at work but, ironically, increase the risk of HIV transmission during non-work sex. SWs recognise this risk and construct a variety of rationales to reduce their fear of contracting HIV and justify their strategies of demarcating work-sex from non-work sex. Efforts to reduce the risk of HIV infection among Perth SWs would seem to depend upon addressing not only these strategies of demarcation but these rationales in a supportive environment that recognises the creative complexities of their lives.  相似文献   
468.
Peer nominations, a central method for measuring peer relationships in developmental research, typically involve asking children or adolescents to choose peers who fit various criteria from an alphabetized roster of classmates or grade‐mates. Although such measures have been used for decades, very little research has investigated the effects of alphabetical name order on the number of nominations received by peers. This study collected peer nominations for 20 items among 607 eighth grade participants in two schools. Regression analyses showed that earlier name order significantly predicted higher nomination counts for eight of the items, and explained over 5 percent of the variance in four affective variables (friendship, acceptance, acquaintanceship, and received liking). Across variables, name order effects were negatively correlated with internal reliability of nominations, implying that order effects may be related to the consensus of the peer group. Name order also had a minimal effect on inter‐correlations among a subset of variables. Implications and concrete recommendations for controlling and reducing name order effects in future research are discussed.  相似文献   
469.
Objectives. We investigate the economic geographies of streets named for Reverend Dr. Martin Luther King, Jr. (MLK Streets), which are an increasingly common means by which various community members across the United States are attempting to commemorate the slain civil rights leader. It is our intent to characterize these negatively “branded” spaces in order to challenge some of the common perceptions about them and inform current and future MLK Street naming debates. Methods. We statistically analyze nonresidential establishments located on streets named for King in terms of scale (as measured by annual sales and employment) and industrial classification. To our knowledge, this is the first such analysis conducted at the national level. Results. Establishments located on MLK Streets do not systematically exhibit economic marginality. Establishments located on these streets do systematically exhibit unique local functions and industrial composition. Conclusion. In the absence of empirically‐driven research, the negative stereotypes that surround MLK Streets have gone unchallenged and are proliferating. The research reported here calls into question a number of these stereotypes and should inform the public, city councils, and other local policymakers, who are increasingly being faced with contentious MLK Street naming debates.  相似文献   
470.
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