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   2991篇
  免费   135篇
  国内免费   10篇
管理学   350篇
民族学   41篇
人才学   1篇
人口学   296篇
丛书文集   49篇
理论方法论   264篇
综合类   330篇
社会学   1228篇
统计学   577篇
  2024年   6篇
  2023年   41篇
  2022年   51篇
  2021年   74篇
  2020年   114篇
  2019年   146篇
  2018年   212篇
  2017年   226篇
  2016年   162篇
  2015年   102篇
  2014年   170篇
  2013年   502篇
  2012年   222篇
  2011年   126篇
  2010年   112篇
  2009年   107篇
  2008年   113篇
  2007年   69篇
  2006年   84篇
  2005年   60篇
  2004年   64篇
  2003年   47篇
  2002年   46篇
  2001年   42篇
  2000年   29篇
  1999年   20篇
  1998年   24篇
  1997年   19篇
  1996年   21篇
  1995年   17篇
  1994年   11篇
  1993年   7篇
  1992年   10篇
  1991年   6篇
  1990年   7篇
  1989年   10篇
  1988年   4篇
  1987年   6篇
  1985年   8篇
  1983年   4篇
  1980年   4篇
  1979年   2篇
  1978年   2篇
  1977年   2篇
  1976年   2篇
  1975年   3篇
  1974年   3篇
  1973年   2篇
  1971年   2篇
  1968年   4篇
排序方式: 共有3136条查询结果,搜索用时 953 毫秒
261.
20世纪初 ,日、俄为争夺中国东北展开了一场激烈的战争。最终 ,俄国以中国的利益为代价 ,暂时满足了日本的扩张野心 ,将俄国在中国东北南部的一切权益 ,未经中国政府同意 ,私下转让给日本。战后 ,日本在中国东北成立了“南满洲铁道株式会社”(简称满铁 )。满铁在对中国进行政治、经济侵略的同时 ,并在其“附属地”内推行“除队兵”移民侵略计划 ,以期达到壮大日本在中国东北的实力 ,抵御俄国的战略目的。但事与愿违 ,由于满铁决策者们的盲目求成 ,移民者的经营不善和厌恶农耕 ,使得满铁“附属地”的“除队兵”移民仅仅推行了 4年时间就以失败而告终  相似文献   
262.
Literature on ambidexterity emphasizes the need for both exploration and exploitation. Large firms usually choose to implement structural ambidexterity to separate both activities. We here focus on an extreme case of such structural partitioning implemented as a secret skunkworks project in a large French automotive company. A qualitative survey using both primary and secondary data shows that the major basic and initial characteristics of a skunkworks (i.e. secrecy, urgency, and autonomy) created favorable conditions for the technological exploration. However, exploitation failed due to precisely those same characteristics coupled with the fact that the project did not respond to a specific market demand: The skunkworks suffered from what we call the "Robinson Crusoe effect." We therefore contribute to the literature on skunkworks, which have remained understudied in the academic literature, as well as on ambidexterity, by showing how the interrelation between different factors is crucial for structural ambidexterity to be successful  相似文献   
263.
Applications of multivariate statistics in engineering are hard to find, apart from those in quality control. However, we think that further insight into some technological cases may be gained by using adequate multivariate analysis tools. In this paper, we propose a review of the key parameters of rotating electric machines with factor analysis. This statistical technique allows not only the reduction of the dimension of the case we are analysing, but also reveals subtle relationships between the variables under study. We show an application of this methodology by studying the interrelations between the key variables in an electric machine, in this case the squirrel-cage induction motor. Through a step-by-step presentation of the case study, we deal with some of the topics an applied researcher may face, such as the rotation of the original factors, the extraction of higher-order factors and the development of the exploratory model. As a result, we present a worthwhile framework to both confirm our previous knowledge and capture unexplored facts. Moreover, it may provide a new approach to describing and understanding the design, performance and operating characteristics of these machines.  相似文献   
264.
This article aims to investigate parental influence on high-risk behavior by young people. Although research on the topic of perception of risk demonstrates that it is socially constructed, the role of the family in this construction has rarely been studied. Using a French national survey of more than 1,200 young drivers between the ages of 18 and 25, and their parents, we attempt to understand the transmission of risk within families. Our econometric study shows that parents influence both the practices and representations of their children. When parental norms and values are transmitted, they are by no means accepted in a wholly passive way. Indeed, the parental model is in competition with other models that originate from both inside the family (brothers and sisters) and outside it (instructors). Furthermore, parental influence decreases over time as young people become more experienced drivers and construct their own identity with regard to risk.  相似文献   
265.
The main models of machine learning are briefly reviewed and considered for building a classifier to identify the Fragile X Syndrome (FXS). We have analyzed 172 patients potentially affected by FXS in Andalusia (Spain) and, by means of a DNA test, each member of the data set is known to belong to one of two classes: affected, not affected. The whole predictor set, formed by 40 variables, and a reduced set with only nine predictors significantly associated with the response are considered. Four alternative base classification models have been investigated: logistic regression, classification trees, multilayer perceptron and support vector machines. For both predictor sets, the best accuracy, considering both the mean and the standard deviation of the test error rate, is achieved by the support vector machines, confirming the increasing importance of this learning algorithm. Three ensemble methods - bagging, random forests and boosting - were also considered, amongst which the bagged versions of support vector machines stand out, especially when they are constructed with the reduced set of predictor variables. The analysis of the sensitivity, the specificity and the area under the ROC curve agrees with the main conclusions extracted from the accuracy results. All of these models can be fitted by free R programs.  相似文献   
266.
汉英广告翻译的策略与方法   总被引:2,自引:0,他引:2  
骆乐 《南都学坛》2000,20(2):58-60
商业广告以促销作为存在的唯一目的。译者在汉语商业广告英译时应当以“功能相似 ,效果相当”为标准 ,根据“强化功能、突出效果、大胆创新”的策略原则 ,使用“删、留、补、掉”四种方法 ,灵活机动地对原文进行大刀阔斧的调整 ,使其符合西方消费者的口味和购买心理 ,以实现最佳的促销效果  相似文献   
267.
Resumen

Este artículo se ha centrado en las limitaciones que han encontrado los intentos de construir modelos formales del conocimiento humano y en el significado de dichas limitaciones. Se ha argumentado que dichas limitaciones tienen su origen en el hecho de que las reglas que constituyen la gramática de la mente son reglas sensibles a los contextos, en oposición a puramente formales.

Todo ello nos ha llevado ha exponer la tesis de que en el mundo social el conocimiento existe encarnado en individuos, pero no puede ser explicado desde el individuo, requiere un marco social. Y si esto es así, la Psicología cognitiva debe ser reinterpretada como psicología social del conocimiento.

Nuestra apuesta personal es que el desarrollo futuro de esta posición será tanto más prometedor cuanto más uso sepa hacer de lo que ya empieza a ser llamado “Epistemología de la complejidad” (véase Jantsch, 1981; Guidano, en prensa; Ibáñez, 1986; Miró en prensa, b). El desarrollo de este reto, sin embargo, pertenece todavía al futuro de la investigación.  相似文献   
268.
This paper deals with the selection of the profiles of weights to be used in cross-efficiency evaluations. In an attempt to prevent unrealistic weighting schemes, one of the issues of main interest that we address here is that of the zero weights, since their use implies that some of the variables considered are excluded from the assessments to be made. In the calculation of cross-efficiency scores, we propose to ignore the profiles of weights of the DMUs that cannot make a choice of non-zero weights among their alternate optima. The different units are therefore assessed in a peer-evaluation that does not consider the profiles of weights of some inefficient DMUs. This approach is referred to as “peer-restricted” cross-efficiency evaluation. Aside from avoiding zero weights, the choice of weights that we make also seeks to reduce the differences between the weights profiles selected as much as possible. Thus, in the “peer-restricted” cross-efficiency evaluation in the present paper we also try to avoid that the different DMUs attach very different weights to the same variable. Finally, we extend this approach to derive a common set of weights by exploiting the idea of similarity between profiles of weights.  相似文献   
269.
Comparative research on inter-municipal cooperation in eight European countries shows that there is a great variety of institutional arrangements for cooperation across the different countries. Also, these arrangements tend to change over time in terms of the scope of cooperation among partners, their composition and the degree of organizational integration. This article describes and analyzes the variety of and shifts in institutional arrangements for a specific class of inter-municipal cooperation arrangements: those that are set up to provide for the joint delivery of public services. It is argued that specific arrangements are typically the outcomes of interaction between national institutional contexts, environmental factors and local preferences.  相似文献   
270.
马丁·艾米斯是一位活跃于后现代的英国作家,深受后现代思潮的影响。但在《时代之箭》中,他却以一位传统作家的姿态,对其叙事手法做了极其大胆的尝试:他拒斥道德相对主义,坚持语言与外部世界的联系,坚持历史书写的指涉性。因此,《时间之箭》在本质上仍然是对启蒙运动以来核心价值观念的坚持与追求。  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