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   158379篇
  免费   4021篇
  国内免费   1611篇
管理学   3776篇
劳动科学   29篇
民族学   2616篇
人才学   20篇
人口学   2241篇
丛书文集   21052篇
理论方法论   6589篇
综合类   113179篇
社会学   5002篇
统计学   9507篇
  2024年   244篇
  2023年   796篇
  2022年   1192篇
  2021年   1323篇
  2020年   1721篇
  2019年   1715篇
  2018年   1802篇
  2017年   2257篇
  2016年   2370篇
  2015年   3168篇
  2014年   7584篇
  2013年   9583篇
  2012年   9484篇
  2011年   11015篇
  2010年   9001篇
  2009年   9277篇
  2008年   9864篇
  2007年   12285篇
  2006年   12402篇
  2005年   11424篇
  2004年   10717篇
  2003年   10467篇
  2002年   8380篇
  2001年   7057篇
  2000年   4018篇
  1999年   1214篇
  1998年   605篇
  1997年   516篇
  1996年   416篇
  1995年   358篇
  1994年   267篇
  1993年   216篇
  1992年   186篇
  1991年   152篇
  1990年   87篇
  1989年   76篇
  1988年   79篇
  1987年   29篇
  1986年   31篇
  1985年   112篇
  1984年   115篇
  1983年   80篇
  1982年   72篇
  1981年   60篇
  1980年   51篇
  1979年   55篇
  1978年   50篇
  1977年   17篇
  1976年   12篇
  1975年   7篇
排序方式: 共有10000条查询结果,搜索用时 46 毫秒
91.
In this article, we describe a straightforward method for solving the probability of at least one malignant cell by time t, and the associated hazard function, in the general (i.e., nonhomogeneous) two-stage Moolgavkar-Venzon-Knudson (MVK) model of cancer. The method consists of solving four coupled ordinary differential equations derived from the Kolmogorov backward equations for this process. The relationship of this method to previously proposed solutions is discussed.  相似文献   
92.
The author characterizes the copula associated with the bivariate survival model of Clayton (1978) as the only absolutely continuous copula that is preserved under bivariate truncation.  相似文献   
93.
文章根据专业学习和技能培训的关系,设计了本科教学的机械设计技能培训模块,为培养大学生的设计技能提供了一个实践平台。  相似文献   
94.
分析了区域裂变后的佛山产业体系发展的现状,并结合佛山未来的经济发展战略,勾勒出佛山目标产业体系,同时提出了以外资的利用作为优化佛山产业体系动力源的对策思路。  相似文献   
95.
96.
Now that evaluators have been sensitized to the importance of moral and ethical issues in their work, it is time to move beyond generalities and examine the moral and ethical implications of specific evaluation models in specific settings. This paper proposes a framework that can be used to examine moral and ethical dimensions of evaluation and illustrates it by analyzing a selected model of mental health evaluation. Such a systematic identification of moral issues can improve evaluation practice both proactively, by shaping the training of evaluators, and retrospectively, by contributing to meta-evaluation.  相似文献   
97.
Ecosystems are formed by organisations that jointly create a value proposition that a single firm could not create in isolation. To deliver this value proposition, the partners need a focal firm, the orchestrator, to be align them towards the joint value proposition. Thus, how orchestrators design the alignment structure of an ecosystem is at the very heart of the ecosystem concept – yet it has not been sufficiently addressed by extant research. This is all the more true for the question of how the design of an ecosystem is shaped depending on surrounding conditions. This paper applies a qualitative study with ten cases and, based on the attention-based view of the firm, contributes to research on ecosystems in several ways. First, it explains which ecosystem designs are beneficial under which conditions. Second, it elucidates the structure and activities within ecosystems and shows that start-ups can be just as good ecosystem orchestrators as incumbents. Third, it explains the circumstances under which single vs. multi orchestrator ecosystems occur. Fourth, it presents the conditions when incumbents or start-ups make better orchestrators. Finally, it is among the first studies to apply the attention-based view to business ecosystems, and shows that doing so yields intriguing insights into this emerging field of research.  相似文献   
98.
This study explores differences in inter-household exchange of goods and services in Anglo- and Mexican-American families controlling for income level and for ethnicity. The extent of such exchange, its perceived importance to the family's quality of life, satisfaction with the exchange, and the relation of persons in the exchange process are examined. Significant differences are found more often between higher income Anglo- and Mexican-Americans than between low-income families, both in the family providing goods and services for others and in the receipt of them. Higher income Mexican-American families are more likely than their Anglo- counterparts to exchange with relatives. Ethnic effects are more prevalent in higher income households than in low-income households. Economic effects are more predominant than ethnic effects.This study contributes to interregional Agricultural Experiment Station Research Project NC-128, Quality of Life as Influenced by Area of Residence. Cooperating states: Arizona, California, Colorado, Illinois, Indiana, Iowa, Kansas, Michigan, Minnesota, Missouri, Nebraska, Nevada, Ohio, Texas.Flora L. Williams' current research interests include income adequacy, financial problems, and indicators of change in economic well-being. She is an Associate Professor, Consumer Sciences and Retailing, Purdue University, West Lafayette, IN 47907.  相似文献   
99.
The paper surveys the currently available axiomatizations of common belief (CB) and common knowledge (CK) by means of modal propositional logics. (Throughout, knowledge — whether individual or common — is defined as true belief.) Section 1 introduces the formal method of axiomatization followed by epistemic logicians, especially the syntax-semantics distinction, and the notion of a soundness and completeness theorem. Section 2 explains the syntactical concepts, while briefly discussing their motivations. Two standard semantic constructions, Kripke structures and neighbourhood structures, are introduced in Sections 3 and 4, respectively. It is recalled that Aumann's partitional model of CK is a particular case of a definition in terms of Kripke structures. The paper also restates the well-known fact that Kripke structures can be regarded as particular cases of neighbourhood structures. Section 3 reviews the soundness and completeness theorems proved w.r.t. the former structures by Fagin, Halpern, Moses and Vardi, as well as related results by Lismont. Section 4 reviews the corresponding theorems derived w.r.t. the latter structures by Lismont and Mongin. A general conclusion of the paper is that the axiomatization of CB does not require as strong systems of individual belief as was originally thought — onlymonotonicity has thusfar proved indispensable. Section 5 explains another consequence of general relevance: despite the infinitary nature of CB, the axiom systems of this paper admit of effective decision procedures, i.e., they aredecidable in the logician's sense.  相似文献   
100.
顾客第一论     
“顾客第一”有其特定的内涵,它充分体现社会主义企业的根本目的,因而是企业所有经营观念中的一个根本性观念,也是企业生产经营的一个根本指导思想。企业要实现其双重目的,促进物质文明和精神文明建设的发展,并树立各种现代经营观念,就必须坚持顾客第一。  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