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   18685篇
  免费   499篇
管理学   2208篇
民族学   110篇
人才学   6篇
人口学   1847篇
丛书文集   106篇
教育普及   2篇
理论方法论   1696篇
现状及发展   1篇
综合类   239篇
社会学   9317篇
统计学   3652篇
  2023年   92篇
  2022年   77篇
  2021年   94篇
  2020年   284篇
  2019年   454篇
  2018年   459篇
  2017年   650篇
  2016年   477篇
  2015年   360篇
  2014年   430篇
  2013年   3115篇
  2012年   662篇
  2011年   589篇
  2010年   457篇
  2009年   432篇
  2008年   494篇
  2007年   501篇
  2006年   457篇
  2005年   613篇
  2004年   481篇
  2003年   410篇
  2002年   387篇
  2001年   465篇
  2000年   382篇
  1999年   376篇
  1998年   308篇
  1997年   278篇
  1996年   287篇
  1995年   274篇
  1994年   257篇
  1993年   249篇
  1992年   289篇
  1991年   288篇
  1990年   259篇
  1989年   257篇
  1988年   244篇
  1987年   227篇
  1986年   218篇
  1985年   246篇
  1984年   234篇
  1983年   233篇
  1982年   177篇
  1981年   155篇
  1980年   170篇
  1979年   171篇
  1978年   142篇
  1977年   140篇
  1976年   122篇
  1975年   116篇
  1974年   96篇
排序方式: 共有10000条查询结果,搜索用时 703 毫秒
991.
This study evaluates the role that religious and cultural values have on individual opinions toward suicide worldwide. Using multilevel modeling with data from the fourth wave of the World Values Survey (42,299 individuals in 43 countries), the current study is designed to analyze the effect of individual (i.e., micro-level), and country (i.e., macro-level) characteristics on opinions toward suicide. Specifically, cultural values, religious affiliation, religious importance, and church attendance are analyzed at both the individual and country levels to evaluate the impact of individual and country level effects on opinions toward suicide. The results show that individual opinions toward suicide are influenced by individual belief as well as by the cultural and religious characteristics of their country. The results suggest that evaluation of individual opinions toward controversial behavior should account for the unique and cross-interaction effects of micro- and macro-level effects.  相似文献   
992.
In this paper, we discuss the bivariate Birnbaum-Saunders accelerated lifetime model, in which we have modeled the dependence structure of bivariate survival data through the use of frailty models. Specifically, we propose the bivariate model Birnbaum-Saunders with the following frailty distributions: gamma, positive stable and logarithmic series. We present a study of inference and diagnostic analysis for the proposed model, more concisely, are proposed a diagnostic analysis based in local influence and residual analysis to assess the fit model, as well as, to detect influential observations. In this regard, we derived the normal curvatures of local influence under different perturbation schemes and we performed some simulation studies for assessing the potential of residuals to detect misspecification in the systematic component, the presence in the stochastic component of the model and to detect outliers. Finally, we apply the methodology studied to real data set from recurrence in times of infections of 38 kidney patients using a portable dialysis machine, we analyzed these data considering independence within the pairs and using the bivariate Birnbaum-Saunders accelerated lifetime model, so that we could make a comparison and verify the importance of modeling dependence within the times of infection associated with the same patient.  相似文献   
993.
This paper analyzes the cost increases due to demand uncertainty in single-level MRP lot sizing on a rolling horizon. It is shown that forecast errors have a tremendous effect on the cost effectiveness of lot-sizing techniques even when these forecast errors are small. Moreover, the cost differences between different techniques become rather insignificant in the presence of forecast errors. Since most industrial firms face demand uncertainty to some extent, our findings may have important managerial implications. Various simulation experiments give insight into both the nature and the magnitude of the cost increases for different heuristics. Analytical results are developed for the constant-demand case with random noise and forecasting by exponential smoothing. It is also shown how optimal buffers can be obtained by use of a simple model. Although the analysis in this paper is restricted to simplified cases, the results merit further consideration and study. This paper is one of the first to inject forecast errors into MRP lot-sizing research. As such it attempts to deal with one of the major objections against the practical relevance of previous research in this area.  相似文献   
994.
This paper applies the patrol-initiated-activity hypercube queuing model to historical data from a police agency. The model allows servers to handle both calls assigned by a central dispatcher and activities initiated by the servers. By duplicating a fairly complex dispatch strategy, the model was found to predict both assigned and server-initiated work loads accurately for the overall system and individual servers. The model is apparently ineffective in predicting small unit-travel-time differences for this police agency.  相似文献   
995.
In this paper we incorporate a linear demand function to model the price-volume causal relationship into stochastic cost-volume-profit (CVP) analysis. We assume that the objective function is to maximize expected profit; other objective functions are also discussed and compared. A linear stochastic model follows from which probabilistic statements can be easily obtained if the random variables are assumed to be multivariate normal. The basic framework is shown to be a special case of project value maximization where project value is the cash flow of the project discounted for time and risk according to the capital asset pricing model. Moreover, an intertemporal extension that considers inventory is developed. In summary, a new approach to stochastic CVP analysis that incorporates the management decision process in an uncertain environment is developed.  相似文献   
996.
数百年来,马尼拉、澳门和广州一直相互依存,保持着密切关系。从16世纪后期至今,三者有着紧密的互动关系,每一城市对其他两者都有着深刻的影响与冲击。这些联系已经维系了几百年,直到今天仍有数万菲律宾人在珠江三角洲生活和工作。牛痘传入澳门和广州或许是巴尔米斯环球之旅的意外收获,但它也确实是三个地区之间长期密切关系的一个表现。在巴尔米斯来到珠江三角洲200周年之际,我们不应忘记三地人民之间在历史上的紧密关系,这一关系仍继续支持和维系着中菲两国,它也将把我们带向未来。  相似文献   
997.
Livingston data on expected inflation rates have been used extensively in the financial literature, especially in investgating the relationship between nominal interest rates and expected inflation rates; however, the data have not been subjected to a thorough analysis of forecast accuracy. The objective of this paper is to analyze the forecast properties of Livingston data using a wide variety of time and frequency domain methods over an extended sample period and for selected subperiods.  相似文献   
998.
This paper reports the findings of a laboratory experiment designed to investigate the relationship of category width (CW) cognitive style with accountants' perceptions of accounting information. Subjects drawn from large accounting firms in Sydney, Brisbane, and Melbourne, Australia, were classified into broad, medium, and narrow categories following the test devised by Pettigrew [19]. Subjects were requested to state their level of confidence in decisions they had made after receiving (1) conventional accounting information or (2) conventional accounting information and human resources accounting (HRA) information using a one-group pretest-posttest design. The results indicated a significant relationship between CW cognitive style and the accountants' confidence in their decisions. Furthermore, CW cognitive style moderated the accounting-information/decision-making relationship.  相似文献   
999.
Perceptions of injustice rely upon a sense-making process in which individuals attempt to understand why and how it occurs. We draw from the attribution-of-blame model of justice judgments to examine how two work groups of disparate status make sense of the treatment and outcomes engendered by their interactions. Data from 27 in-depth interviews with custodians and teachers reveal that when custodians perceive disrespect from teachers and teachers perceive that custodians do not fulfill properly their duties, their attributions are shaped by their status position. Although both make internal attributions to each other for their injustice, teachers do not recognize how they perpetrate injustice against custodians and custodians perceive greater injustice by identifying how external factors affect their performance and blame. This unjustified blame fosters counterproductive work behaviors, illustrating how interdependencies fuel a cycle of injustice. We discuss the implications of these findings for the school and justice processes.  相似文献   
1000.
The run sum chart is an effective two-sided chart that can be used to monitor for process changes. It is known that it is more sensible than the Shewhart chart with runs rules and its performance improves as the number of regions increases. However, as the number of regions increses the resulting chart has more parameters to be defined and its design becomes more involved. In this article, we introduce a one-parameter run sum chart. This chart accumulates scores equal to the subgroup means and signals when the cummulative sum exceeds a limit value. A fast initial response feature is proposed and its run length distribution function is found by a set of recursive relations. We compare this chart with other charts suggested in the literature and find it competitive with the CUSUM, the FIR CUSUM, and the combined Shewhart FIR CUSUM schemes.  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