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   4088篇
  免费   632篇
管理学   1098篇
民族学   6篇
人口学   45篇
丛书文集   2篇
理论方法论   817篇
综合类   45篇
社会学   1625篇
统计学   1082篇
  2021年   94篇
  2020年   161篇
  2019年   336篇
  2018年   206篇
  2017年   356篇
  2016年   351篇
  2015年   340篇
  2014年   359篇
  2013年   567篇
  2012年   366篇
  2011年   250篇
  2010年   263篇
  2009年   148篇
  2008年   190篇
  2007年   98篇
  2006年   107篇
  2005年   94篇
  2004年   106篇
  2003年   72篇
  2002年   79篇
  2001年   86篇
  2000年   68篇
  1999年   5篇
  1998年   2篇
  1997年   2篇
  1996年   2篇
  1995年   3篇
  1994年   2篇
  1992年   3篇
  1990年   1篇
  1982年   1篇
  1981年   1篇
  1977年   1篇
排序方式: 共有4720条查询结果,搜索用时 15 毫秒
31.
Anthropogenic climate change information tends to be interpreted against the backdrop of initial environmental beliefs, which can lead to some people being resistant toward the information. In this article (N = 88), we examined whether self‐affirmation via reflection on personally important values could attenuate the impact of initial beliefs on the acceptance of anthropogenic climate change evidence. Our findings showed that initial beliefs about the human impact on ecological stability influenced the acceptance of information only among nonaffirmed participants. Self‐affirmed participants who were initially resistant toward the information showed stronger beliefs in the existence of climate change risks and greater acknowledgment that individual efficacy has a role to play in reducing climate change risks than did their nonaffirmed counterparts.  相似文献   
32.
In risk assessment, the moment‐independent sensitivity analysis (SA) technique for reducing the model uncertainty has attracted a great deal of attention from analysts and practitioners. It aims at measuring the relative importance of an individual input, or a set of inputs, in determining the uncertainty of model output by looking at the entire distribution range of model output. In this article, along the lines of Plischke et al., we point out that the original moment‐independent SA index (also called delta index) can also be interpreted as the dependence measure between model output and input variables, and introduce another moment‐independent SA index (called extended delta index) based on copula. Then, nonparametric methods for estimating the delta and extended delta indices are proposed. Both methods need only a set of samples to compute all the indices; thus, they conquer the problem of the “curse of dimensionality.” At last, an analytical test example, a risk assessment model, and the levelE model are employed for comparing the delta and the extended delta indices and testing the two calculation methods. Results show that the delta and the extended delta indices produce the same importance ranking in these three test examples. It is also shown that these two proposed calculation methods dramatically reduce the computational burden.  相似文献   
33.
The three classic pillars of risk analysis are risk assessment (how big is the risk and how sure can we be?), risk management (what shall we do about it?), and risk communication (what shall we say about it, to whom, when, and how?). We propose two complements as important parts of these three bases: risk attribution (who or what addressable conditions actually caused an accident or loss?) and learning from experience about risk reduction (what works, and how well?). Failures in complex systems usually evoke blame, often with insufficient attention to root causes of failure, including some aspects of the situation, design decisions, or social norms and culture. Focusing on blame, however, can inhibit effective learning, instead eliciting excuses to deflect attention and perceived culpability. Productive understanding of what went wrong, and how to do better, thus requires moving past recrimination and excuses. This article identifies common blame‐shifting “lame excuses” for poor risk management. These generally contribute little to effective improvements and may leave real risks and preventable causes unaddressed. We propose principles from risk and decision sciences and organizational design to improve results. These start with organizational leadership. More specifically, they include: deliberate testing and learning—especially from near‐misses and accident precursors; careful causal analysis of accidents; risk quantification; candid expression of uncertainties about costs and benefits of risk‐reduction options; optimization of tradeoffs between gathering additional information and immediate action; promotion of safety culture; and mindful allocation of people, responsibilities, and resources to reduce risks. We propose that these principles provide sound foundations for improving successful risk management.  相似文献   
34.
The effect of bioaerosol size was incorporated into predictive dose‐response models for the effects of inhaled aerosols of Francisella tularensis (the causative agent of tularemia) on rhesus monkeys and guinea pigs with bioaerosol diameters ranging between 1.0 and 24 μm. Aerosol‐size‐dependent models were formulated as modification of the exponential and β‐Poisson dose‐response models and model parameters were estimated using maximum likelihood methods and multiple data sets of quantal dose‐response data for which aerosol sizes of inhaled doses were known. Analysis of F. tularensis dose‐response data was best fit by an exponential dose‐response model with a power function including the particle diameter size substituting for the rate parameter k scaling the applied dose. There were differences in the pathogen's aerosol‐size‐dependence equation and models that better represent the observed dose‐response results than the estimate derived from applying the model developed by the International Commission on Radiological Protection (ICRP, 1994) that relies on differential regional lung deposition for human particle exposure.  相似文献   
35.
In chemical and microbial risk assessments, risk assessors fit dose‐response models to high‐dose data and extrapolate downward to risk levels in the range of 1–10%. Although multiple dose‐response models may be able to fit the data adequately in the experimental range, the estimated effective dose (ED) corresponding to an extremely small risk can be substantially different from model to model. In this respect, model averaging (MA) provides more robustness than a single dose‐response model in the point and interval estimation of an ED. In MA, accounting for both data uncertainty and model uncertainty is crucial, but addressing model uncertainty is not achieved simply by increasing the number of models in a model space. A plausible set of models for MA can be characterized by goodness of fit and diversity surrounding the truth. We propose a diversity index (DI) to balance between these two characteristics in model space selection. It addresses a collective property of a model space rather than individual performance of each model. Tuning parameters in the DI control the size of the model space for MA.  相似文献   
36.
Land subsidence risk assessment (LSRA) is a multi‐attribute decision analysis (MADA) problem and is often characterized by both quantitative and qualitative attributes with various types of uncertainty. Therefore, the problem needs to be modeled and analyzed using methods that can handle uncertainty. In this article, we propose an integrated assessment model based on the evidential reasoning (ER) algorithm and fuzzy set theory. The assessment model is structured as a hierarchical framework that regards land subsidence risk as a composite of two key factors: hazard and vulnerability. These factors can be described by a set of basic indicators defined by assessment grades with attributes for transforming both numerical data and subjective judgments into a belief structure. The factor‐level attributes of hazard and vulnerability are combined using the ER algorithm, which is based on the information from a belief structure calculated by the Dempster‐Shafer (D‐S) theory, and a distributed fuzzy belief structure calculated by fuzzy set theory. The results from the combined algorithms yield distributed assessment grade matrices. The application of the model to the Xixi‐Chengnan area, China, illustrates its usefulness and validity for LSRA. The model utilizes a combination of all types of evidence, including all assessment information—quantitative or qualitative, complete or incomplete, and precise or imprecise—to provide assessment grades that define risk assessment on the basis of hazard and vulnerability. The results will enable risk managers to apply different risk prevention measures and mitigation planning based on the calculated risk states.  相似文献   
37.
A challenge for large‐scale environmental health investigations such as the National Children's Study (NCS), is characterizing exposures to multiple, co‐occurring chemical agents with varying spatiotemporal concentrations and consequences modulated by biochemical, physiological, behavioral, socioeconomic, and environmental factors. Such investigations can benefit from systematic retrieval, analysis, and integration of diverse extant information on both contaminant patterns and exposure‐relevant factors. This requires development, evaluation, and deployment of informatics methods that support flexible access and analysis of multiattribute data across multiple spatiotemporal scales. A new “Tiered Exposure Ranking” (TiER) framework, developed to support various aspects of risk‐relevant exposure characterization, is described here, with examples demonstrating its application to the NCS. TiER utilizes advances in informatics computational methods, extant database content and availability, and integrative environmental/exposure/biological modeling to support both “discovery‐driven” and “hypothesis‐driven” analyses. “Tier 1” applications focus on “exposomic” pattern recognition for extracting information from multidimensional data sets, whereas second and higher tier applications utilize mechanistic models to develop risk‐relevant exposure metrics for populations and individuals. In this article, “tier 1” applications of TiER explore identification of potentially causative associations among risk factors, for prioritizing further studies, by considering publicly available demographic/socioeconomic, behavioral, and environmental data in relation to two health endpoints (preterm birth and low birth weight). A “tier 2” application develops estimates of pollutant mixture inhalation exposure indices for NCS counties, formulated to support risk characterization for these endpoints. Applications of TiER demonstrate the feasibility of developing risk‐relevant exposure characterizations for pollutants using extant environmental and demographic/socioeconomic data.  相似文献   
38.
This paper describes how government policy thinking about the well‐being of children and young people developed between the Children Act 1989 and the Children Act 2004. These two Acts are milestone statements about how services to children in England and Wales should be delivered. It is an account informed by the author's own experience as a government adviser on children's social care over much of this period and supporting documentation. It traces the strands of government policy thinking about how to deliver services for children from children in need to the articulation of the five Every Child Matters outcomes. It argues that attempts to achieve coordinated service planning for children and young people played a significant role in the formulation of shared objectives and the articulation of child outcomes. However, it argues that looking at real outcomes exposes how children in the UK do relatively badly compared with other rich nations. It questions whether we can realistically expect our services to deliver significantly improved outcomes given the impact of enduring inequality in our society. This paper is dedicated to the memory of David Lambert CBE, former Assistant Chief Inspector of the Social Services Inspectorate in London, who died suddenly on 7 October 2010. He lent me articles to assist me in writing this paper.  相似文献   
39.
A driving force behind the establishment of a qualitative data archive in the United Kingdom has been the oral historian, Paul Thompson. He has complained that there is a ‘strange silence’ among qualitative sociologists on re‐analysis, and that many have been reluctant to deposit data. The first part of the paper suggests that the common ethical and practical objections can be overcome in establishing an archive in Australia. However, there is a more serious underlying ideological objection: that archiving promotes and institutionalises a narrow empiricist version of qualitative research. The rest of the paper makes this case by examining teaching materials on a British website, by reviewing Thompson's arguments, and by considering some examples of re‐analysis by sociologists. It is argued that qualitative researchers should respond critically, but that it is possible to address and overcome these problems when developing an Australian archive.  相似文献   
40.
We examine the relationship between vocational education and occupational burnout among workers in different forms of employment. Although the self‐employed enjoy higher levels of job autonomy and work‐related satisfaction, we do not know whether they experience lower rates of occupational burnout, and whether vocational education plays a role in this relationship. This latter consideration is important, given that vocational qualifications often lead to self‐employment and prior research demonstrated that formal training may reduce burnout. However, formal education was previously measured in years of schooling, without considering the distinction between academically‐oriented and vocational courses. Therefore, using data from a 2001 national survey of working Australians, we first establish that the self‐employed are significantly less likely to experience burnout. We then demonstrate that some resilience to burnout can be attributed to the attainment of skilled vocational training, net of employment characteristics which are also very important.  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