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   2460篇
  免费   92篇
  国内免费   19篇
管理学   267篇
劳动科学   2篇
民族学   13篇
人口学   47篇
丛书文集   183篇
理论方法论   185篇
综合类   1134篇
社会学   187篇
统计学   553篇
  2024年   2篇
  2023年   13篇
  2022年   6篇
  2021年   17篇
  2020年   37篇
  2019年   48篇
  2018年   49篇
  2017年   85篇
  2016年   62篇
  2015年   60篇
  2014年   130篇
  2013年   316篇
  2012年   147篇
  2011年   128篇
  2010年   127篇
  2009年   132篇
  2008年   136篇
  2007年   161篇
  2006年   154篇
  2005年   149篇
  2004年   114篇
  2003年   120篇
  2002年   115篇
  2001年   82篇
  2000年   53篇
  1999年   24篇
  1998年   18篇
  1997年   12篇
  1996年   14篇
  1995年   5篇
  1994年   5篇
  1993年   7篇
  1992年   4篇
  1991年   8篇
  1990年   1篇
  1989年   5篇
  1988年   5篇
  1987年   1篇
  1986年   2篇
  1985年   1篇
  1984年   3篇
  1983年   1篇
  1981年   3篇
  1980年   3篇
  1978年   3篇
  1977年   1篇
  1976年   1篇
  1973年   1篇
排序方式: 共有2571条查询结果,搜索用时 593 毫秒
41.
In this article, a system that consists of n independent components each having two dependent subcomponents (Ai, Bi), i = 1, …, n is considered. The system is assumed to compose of components that have two correlated subcomponents (Ai, Bi), and functions iff both systems of subcomponents A1, A2, …, An and B1, B2, …, Bn work under certain structural rules. The expressions for reliability and mean time to failure of such systems are obtained. A sufficient condition to compare two systems of bivariate components in terms of stochastic ordering is also presented.  相似文献   
42.
We propose new dynamic measures of uncertainty based on the notion of generalized dynamic entropy introduced in Di Crescenzo and Longobardi (2006). These can uniquely determine distribution functions in continuous and discrete cases, and the characterizations of some well-known distributions are provided. We also define some orderings and aging notions based on the generalized dynamic measures, and prove some of their properties, obtaining as corollaries results that have recently appeared in the literature.  相似文献   
43.
When considering systems statisfying balanced incomplete block design structure, one is interested only in distinct configurations in the sense of isomorphism. We have determined additional non-isomorphic solutions to designs with previously established solutions through consideration of automorphism groups. This effort utilizes a classic technique of direct construction, namely, symmetrically repeated differences, modified slightly when constucting designs with partial cycles of blocks. To determine te base blocks, we utilize the computer to expedite some formidable enumeration  相似文献   
44.
In this paper, semiparametric methods are applied to estimate multivariate volatility functions, using a residual approach as in [J. Fan and Q. Yao, Efficient estimation of conditional variance functions in stochastic regression, Biometrika 85 (1998), pp. 645–660; F.A. Ziegelmann, Nonparametric estimation of volatility functions: The local exponential estimator, Econometric Theory 18 (2002), pp. 985–991; F.A. Ziegelmann, A local linear least-absolute-deviations estimator of volatility, Comm. Statist. Simulation Comput. 37 (2008), pp. 1543–1564], among others. Our main goal here is two-fold: (1) describe and implement a number of semiparametric models, such as additive, single-index and (adaptive) functional-coefficient, in volatility estimation, all motivated as alternatives to deal with the curse of dimensionality present in fully nonparametric models; and (2) propose the use of a variation of the traditional cross-validation method to deal with model choice in the class of adaptive functional-coefficient models, choosing simultaneously the bandwidth, the number of covariates in the model and also the single-index smoothing variable. The modified cross-validation algorithm is able to tackle the computational burden caused by the model complexity, providing an important tool in semiparametric volatility estimation. We briefly discuss model identifiability when estimating volatility as well as nonnegativity of the resulting estimators. Furthermore, Monte Carlo simulations for several underlying generating models are implemented and applications to real data are provided.  相似文献   
45.
We consider a problem of evaluating efficiency of Decision Making Units (DMUs) based on their deterministic performance on multiple consumed inputs and multiple produced outputs. We apply a ratio-based efficiency measure, and account for the Decision Maker׳s preference information representable with linear constraints involving input/output weights. We analyze the set of all feasible weights to answer various robustness concerns by deriving: (1) extreme efficiency scores and (2) extreme efficiency ranks for each DMU, (3) possible and necessary efficiency preference relations for pairs of DMUs, (4) efficiency distribution, (5) efficiency rank acceptability indices, and (6) pairwise efficiency outranking indices. The proposed hybrid approach combines and extends previous results from Ratio-based Efficiency Analysis and the SMAA-D method. The practical managerial implications are derived from the complementary character of accounted perspectives on DMUs׳ efficiencies. We present an innovative open-source software implementing an integrated framework for robustness analysis using a ratio-based efficiency model on the diviz platform. The proposed approach is applied to a real-world problem of evaluating efficiency of Polish airports. We consider four inputs related to the capacities of a terminal, runways, and an apron, and to the airport׳s catchment area, and two outputs concerning passenger traffic and number of aircraft movements. We present how the results can be affected by integrating the weight constraints and eliminating outlier DMUs.  相似文献   
46.
This paper explores one aspect of unresolved trauma, namely dissociation. Its relevance to child protection is discussed with reference to two aspects: emotional neglect and choice of partner. There is an exploration of the implications for both assessment and treatment. The central place of shame in relation to dissociation is also explored. It is argued that dissociation is an important concept in child protection assessments and that social work assessments should be alert to this.  相似文献   
47.
In modeling disease transmission, contacts are assumed to have different infection rates. A proper simulation must model the heterogeneity in the transmission rates. In this article, we present a computationally efficient algorithm that can be applied to a population with heterogeneous transmission rates. We conducted a simulation study to show that the algorithm is more efficient than other algorithms for sampling the disease transmission in a subset of the heterogeneous population. We use a valid stochastic model of pandemic influenza to illustrate the algorithm and to estimate the overall infection attack rates of influenza A (H1N1) in a Canadian city.  相似文献   
48.
In this article, to reduce computational load in performing Bayesian variable selection, we used a variant of reversible jump Markov chain Monte Carlo methods, and the Holmes and Held (HH) algorithm, to sample model index variables in logistic mixed models involving a large number of explanatory variables. Furthermore, we proposed a simple proposal distribution for model index variables, and used a simulation study and real example to compare the performance of the HH algorithm with our proposed and existing proposal distributions. The results show that the HH algorithm with our proposed proposal distribution is a computationally efficient and reliable selection method.  相似文献   
49.
自20世纪70年代吉伯德-萨特思韦特防策略不可能性定理确立后,引起了数学、经济学、计算机科学和哲学等诸多领域中学者的广泛关注。然而,在国内外文献中,对吉伯德-萨特思韦特防策略不可能性定理的逻辑研究还比较少。基于此,借助公理化的方法探讨吉伯德-萨特思韦特防策略不可能性定理,并形式化地给出定理的内容和证明,力图把精细的逻辑推理应用于复杂的过程分析中,使防策略投票这一过程形式化、清晰化,以期能指导人们进行合理、有效的决策活动。  相似文献   
50.
我国宪法赋予了公民用自己的民族语言文字参加诉讼的权利,目的在于实现民族平等、促进民族团结、禁止民族分裂、保护中华民族语言文化的多样性,进而提高我国的文化软实力。通过调查民族语言文字诉讼司法实务,发现当前存在着少数民族语言文字诉讼程序混乱、不符合诉讼原理等问题,不利于民族语言文字诉讼权利的实现。究其原因,在于该诉讼制度缺乏程序保障。为了确保民族语言文字诉讼权利的有效实现,应设立“民汉双语诉讼规则”,以为司法机关提供统一的操作规范。民汉双语诉讼规则应该明确民汉双语诉讼的概念、类型以及民族语言文字诉讼权利的内容,并且根据不同诉讼类型有针对性地设置审判语言与诉讼语言的适用规则。  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