全文获取类型
收费全文 | 16674篇 |
免费 | 703篇 |
国内免费 | 220篇 |
专业分类
管理学 | 1539篇 |
劳动科学 | 2篇 |
民族学 | 159篇 |
人才学 | 1篇 |
人口学 | 409篇 |
丛书文集 | 1190篇 |
理论方法论 | 602篇 |
综合类 | 9713篇 |
社会学 | 1410篇 |
统计学 | 2572篇 |
出版年
2024年 | 21篇 |
2023年 | 148篇 |
2022年 | 137篇 |
2021年 | 193篇 |
2020年 | 325篇 |
2019年 | 375篇 |
2018年 | 428篇 |
2017年 | 508篇 |
2016年 | 462篇 |
2015年 | 557篇 |
2014年 | 931篇 |
2013年 | 1701篇 |
2012年 | 1179篇 |
2011年 | 1197篇 |
2010年 | 981篇 |
2009年 | 892篇 |
2008年 | 1005篇 |
2007年 | 1120篇 |
2006年 | 1022篇 |
2005年 | 893篇 |
2004年 | 778篇 |
2003年 | 636篇 |
2002年 | 542篇 |
2001年 | 413篇 |
2000年 | 296篇 |
1999年 | 157篇 |
1998年 | 90篇 |
1997年 | 91篇 |
1996年 | 85篇 |
1995年 | 66篇 |
1994年 | 60篇 |
1993年 | 56篇 |
1992年 | 42篇 |
1991年 | 23篇 |
1990年 | 29篇 |
1989年 | 33篇 |
1988年 | 24篇 |
1987年 | 23篇 |
1986年 | 21篇 |
1985年 | 14篇 |
1984年 | 15篇 |
1983年 | 7篇 |
1982年 | 6篇 |
1981年 | 9篇 |
1980年 | 2篇 |
1979年 | 1篇 |
1978年 | 1篇 |
1977年 | 1篇 |
1975年 | 1篇 |
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
11.
《Risk analysis》2018,38(8):1559-1575
Security of the systems is normally interdependent in such a way that security risks of one part affect other parts and threats spread through the vulnerable links in the network. So, the risks of the systems can be mitigated through investments in the security of interconnecting links. This article takes an innovative look at the problem of security investment of nodes on their vulnerable links in a given contagious network as a game‐theoretic model that can be applied to a variety of applications including information systems. In the proposed game model, each node computes its corresponding risk based on the value of its assets, vulnerabilities, and threats to determine the optimum level of security investments on its external links respecting its limited budget. Furthermore, direct and indirect nonlinear influences of a node's security investment on the risks of other nodes are considered. The existence and uniqueness of the game's Nash equilibrium in the proposed game are also proved. Further analysis of the model in a practical case revealed that taking advantage of the investment effects of other players, perfectly rational players (i.e., those who use the utility function of the proposed game model) make more cost‐effective decisions than selfish nonrational or semirational players. 相似文献
12.
AbstractIn general, survival data are time-to-event data, such as time to death, time to appearance of a tumor, or time to recurrence of a disease. Models for survival data have frequently been based on the proportional hazards model, proposed by Cox. The Cox model has intensive application in the field of social, medical, behavioral and public health sciences. In this paper we propose a more efficient sampling method of recruiting subjects for survival analysis. We propose using a Moving Extreme Ranked Set Sampling (MERSS) scheme with ranking based on an easy-to-evaluate baseline auxiliary variable known to be associated with survival time. This paper demonstrates that this approach provides a more powerful testing procedure as well as a more efficient estimate of hazard ratio than that based on simple random sampling (SRS). Theoretical derivation and simulation studies are provided. The Iowa 65+ Rural study data are used to illustrate the methods developed in this paper. 相似文献
13.
Sampo Varjonen 《International Journal of Social Welfare》2020,29(1):62-70
Historical institutionalist studies have explained institutional change as resulting from critical junctures that interrupt long periods of stability or from endogenous, incremental evolution. Building on these theories, discursive institutionalists have focused on the roles of agency, ideas and discourse as explainers of change. Combining these approaches, this article analyses Finland’s decision in 2014 to transfer the administration of basic social assistance from municipalities to the central government. This study demonstrates that institutional change can be both abrupt and evolutionary. Due to sudden, exceptional political circumstances, the decision in question was made quickly and under pressure, circumventing possible veto players. However, it was possible only because of the incremental, endogenous change that had occurred in the way in which social assistance was administered at the municipal level. It enabled a change in political discourse, which eroded the credibility of the ideational frames that policy actors had previously utilised to reject the centralised model. 相似文献
14.
Keisuke Himoto 《Risk analysis》2020,40(6):1124-1138
Post-earthquake fires are high-consequence events with extensive damage potential. They are also low-frequency events, so their nature remains underinvestigated. One difficulty in modeling post-earthquake ignition probabilities is reducing the model uncertainty attributed to the scarce source data. The data scarcity problem has been resolved by pooling the data indiscriminately collected from multiple earthquakes. However, this approach neglects the inter-earthquake heterogeneity in the regional and seasonal characteristics, which is indispensable for risk assessment of future post-earthquake fires. Thus, the present study analyzes the post-earthquake ignition probabilities of five major earthquakes in Japan from 1995 to 2016 (1995 Kobe, 2003 Tokachi-oki, 2004 Niigata–Chuetsu, 2011 Tohoku, and 2016 Kumamoto earthquakes) by a hierarchical Bayesian approach. As the ignition causes of earthquakes share a certain commonality, common prior distributions were assigned to the parameters, and samples were drawn from the target posterior distribution of the parameters by a Markov chain Monte Carlo simulation. The results of the hierarchical model were comparatively analyzed with those of pooled and independent models. Although the pooled and hierarchical models were both robust in comparison with the independent model, the pooled model underestimated the ignition probabilities of earthquakes with few data samples. Among the tested models, the hierarchical model was least affected by the source-to-source variability in the data. The heterogeneity of post-earthquake ignitions with different regional and seasonal characteristics has long been desired in the modeling of post-earthquake ignition probabilities but has not been properly considered in the existing approaches. The presented hierarchical Bayesian approach provides a systematic and rational framework to effectively cope with this problem, which consequently enhances the statistical reliability and stability of estimating post-earthquake ignition probabilities. 相似文献
15.
The widely used empirical Bayes (EB) and full Bayes (FB) methods for before–after safety assessment are sometimes limited because of the extensive data needs from additional reference sites. To address this issue, this study proposes a novel before–after safety evaluation methodology based on survival analysis and longitudinal data as an alternative to the EB/FB method. A Bayesian survival analysis (SARE) model with a random effect term to address the unobserved heterogeneity across sites is developed. The proposed survival analysis method is validated through a simulation study before its application. Subsequently, the SARE model is developed in a case study to evaluate the safety effectiveness of a recent red‐light‐running photo enforcement program in New Jersey. As demonstrated in the simulation and the case study, the survival analysis can provide valid estimates using only data from treated sites, and thus its results will not be affected by the selection of defective or insufficient reference sites. In addition, the proposed approach can take into account the censored data generated due to the transition from the before period to the after period, which has not been previously explored in the literature. Using individual crashes as units of analysis, survival analysis can incorporate longitudinal covariates such as the traffic volume and weather variation, and thus can explicitly account for the potential temporal heterogeneity. 相似文献
16.
Jacob Mukherjee 《The British journal of sociology》2020,71(4):644-657
This essay, based on a “militant ethnography” of the attempts of the small radical grassroots activist group, Our London (a pseudonym), to mobilize a collective oppositional politics through activities around an election campaign, engages critically with E. Laclau and C. Mouffe's arguments on discourse and collectivity in Hegemony and Socialist Strategy (London: Verso, 1985). I argue, on the basis of my findings, that while their model does provide insights that help describe the process of building collectivity from among disparate perspectives and identities, we need to go beyond a focus on discourse alone and consider the ways politics is shaped by material contexts. This is necessary if we are to understand the continued appeal of class politics as well as the difficulties in mobilizing collectivity in highly unequal and fragmented cities. From an activist perspective, the essay also highlights how developing a conception of collective interests and a critique of overarching systems of exploitation can be important in building political unity. 相似文献
17.
Increased juvenile delinquency can be seen as an indicator for a deteriorating social fabric under conditions of rapid social change. Criminological theories suggest, however, that such conditions do not per se produce delinquency: They force youth into prodelinquent leisure activities with peers, leading to an endorsement of delinquent behavior and offering the infrastructure for it. Resources acquired in family and public life, however, may prevent youth from drifting into such prodelinquent leisure activities and indirectly from delinquent behavior. Empirical tests of these hypotheses have to employ simultaneous analyses of societal-level and individual-level data. On the basis of an international youth study, the paper undertakes such an analysis: In the years 1992–95, data from 42 independent samples of seventh graders from East and West Germany, Poland, Russia, Bulgaria, Slovakia, Hungary, Czechia, and Greece were surveyed. Data on deviant school behavior, delinquent drift, nurturant parenting, and subjective feelings of justice in public were obtained from 7282 thirteen- to fourteen-year-olds. Processes of rapid social change were incorporated as data on changes in GNP in the years proceeding the surveys. Analyses show that delinquent drift is a valid predictor of deviant school behavior only on the individual level. The extent to which adolescents engage in prodelinquent peer activities depends more on the cultural context in which adolescents live than on their personal experience in the family and in public. Nurturant parenting does, however, covary negatively with deviant school behavior irrespective of level of analysis. 相似文献
18.
Sue Blackwell 《Journal of Sociolinguistics》2002,6(4):589-597
Book reviewed in this article:
Joan Dunayer, Animal Equality: Language and Liberation 相似文献
Joan Dunayer, Animal Equality: Language and Liberation 相似文献
19.
JOURNAL OF UNIVERSITY OF SHANGHAI FOR SCIENCE AND TECHNOLOGY 2002 Vol.24 No.1~4 Total Contents 总被引:1,自引:0,他引:1
在学习英语时,中西文化背景的差异,往往会给我们的阅读带来很大的困难。本文拟从词汇的文化内涵、历史典故和西方现代历史文化等三个方面来论述中西文化差异对篇章阅读的影响。 相似文献
20.
本论文主要讨论了基于WEB远程教学管理软件的分析与设计。首先对远程教育与传统教育进行了比较研究,确定远程教育是现代教育发展的方向;其次对开发基于WEB远程教学管理软件进行了环境分析和需求分析;最后讨论了远程教学管理软件的实现,包括软件模块结构设计和网站的总体框架。 相似文献