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   275篇
  免费   11篇
  国内免费   1篇
管理学   57篇
民族学   2篇
人口学   22篇
理论方法论   32篇
综合类   3篇
社会学   143篇
统计学   28篇
  2023年   1篇
  2022年   1篇
  2021年   3篇
  2020年   11篇
  2019年   15篇
  2018年   9篇
  2017年   17篇
  2016年   17篇
  2015年   7篇
  2014年   15篇
  2013年   42篇
  2012年   15篇
  2011年   11篇
  2010年   8篇
  2009年   8篇
  2008年   12篇
  2007年   6篇
  2006年   12篇
  2005年   11篇
  2004年   8篇
  2003年   5篇
  2002年   4篇
  2000年   10篇
  1999年   6篇
  1998年   4篇
  1997年   2篇
  1996年   1篇
  1995年   4篇
  1994年   2篇
  1993年   1篇
  1992年   3篇
  1991年   1篇
  1989年   3篇
  1987年   1篇
  1986年   2篇
  1985年   1篇
  1984年   1篇
  1981年   2篇
  1980年   1篇
  1979年   2篇
  1978年   1篇
  1977年   1篇
排序方式: 共有287条查询结果,搜索用时 0 毫秒
231.
Due to differences in definitions and measurement methods, cross-country comparisons of international migration patterns are difficult and confusing. Emigration numbers reported by sending countries tend to differ from the corresponding immigration numbers reported by receiving countries. In this paper, a methodology is presented to achieve harmonised estimates of migration flows benchmarked to a specific definition of duration. This methodology accounts for both differences in definitions and the effects of measurement error due to, for example, under reporting and sampling fluctuations. More specifically, the differences between the two sets of reported data are overcome by estimating a set of adjustment factors for each country’s immigration and emigration data. The adjusted data take into account any special cases where the origin–destination patterns do not match the overall patterns. The new method for harmonising migration flows that we present is based on earlier efforts by Poulain (European Journal of Population, 9(4): 353–381 1993, Working Paper 12, joint ECE-Eurostat Work Session on Migration Statistics, Geneva, Switzerland 1999) and is illustrated for movements between 19 European countries from 2002 to 2007. The results represent a reliable and consistent set of international migration flows that can be used for understanding recent changes in migration patterns, as inputs into population projections and for developing evidence-based migration policies.  相似文献   
232.
Cross-contamination and undercooking are major factors responsible for campylobacteriosis and as such should be incorporated in microbiological risk assessment. A previous paper by van Asselt et al. ( 1 ) quantified cross-contamination routes from chicken breast fillet via hand, cutting board, and knife ending up in a prepared chicken-curry salad in the domestic kitchen. The aim of the current article was to validate the obtained transfer rates with consumer data obtained by video observations and microbial analyses of a home prepared chicken-curry salad. Results showed a wide range of microbial contamination levels in the final salad, caused by various cross-contamination practices and heating times varying from 2'44 to 41'30. Model predictions indicated that cooking times should be at least 8 minutes and cutting boards need to be changed after cutting raw chicken in order to obtain safe bacterial levels in the final salad. The model predicted around 75% of the variance in cross-contamination behavior. Accuracy of the model can further be improved by including other cross-contamination routes besides hands, cutting boards, and knives. The model proved to be fail-safe, which implies it can be used as a worst-case estimate to assess the importance of cross-contamination in the home.  相似文献   
233.
234.
235.
Individual-level models (ILMs) for infectious disease can be used to model disease spread between individuals while taking into account important covariates. One important covariate in determining the risk of infection transfer can be spatial location. At the same time, measurement error is a concern in many areas of statistical analysis, and infectious disease modelling is no exception. In this paper, we are concerned with the issue of measurement error in the recorded location of individuals when using a simple spatial ILM to model the spread of disease within a population. An ILM that incorporates spatial location random effects is introduced within a hierarchical Bayesian framework. This model is tested upon both simulated data and data from the UK 2001 foot-and-mouth disease epidemic. The ability of the model to successfully identify both the spatial infection kernel and the basic reproduction number (R 0) of the disease is tested.  相似文献   
236.
237.
ABSTRACT

In a landmark study in 2006, Bartlett and DeSteno found that receiving help promoted reciprocal behavior and that this effect was mediated by gratitude. Recent research, however, suggested that indebtedness is more closely associated with reciprocation than gratitude. Therefore, we examined whether reciprocal behavior could (also) be attributed to indebtedness. Specifically, we attempted to replicate and extend Bartlett and DeSteno’s Study 1 by additionally including a measure of indebtedness. Surprisingly, the replication was not successful. We did not find support for the idea that receiving help promoted reciprocal behavior, and neither gratitude nor indebtedness was associated with reciprocal behavior. Finally, we call for attention that the extant literature may be inconclusive regarding the presumed prosocial effects of gratitude.  相似文献   
238.
The significance of petting zoos for transmission of Campylobacter to humans and the effect of interventions were estimated. A stochastic QMRA model simulating a child or adult visiting a Dutch petting zoo was built. The model describes the transmission of Campylobacter in animal feces from the various animal species, fences, and the playground to ingestion by visitors through touching these so‐called carriers and subsequently touching their lips. Extensive field and laboratory research was done to fulfill data needs. Fecal contamination on all carriers was measured by swabbing in 10 petting zoos, using Escherichia coli as an indicator. Carrier‐hand and hand‐lip touching frequencies were estimated by, in total, 13 days of observations of visitors by two observers at two petting zoos. The transmission from carrier to hand and from hand to lip by touching was measured using preapplied cow feces to which E. coli WG5 was added as an indicator. Via a Beta‐Poisson dose‐response function, the number of Campylobacter cases for the whole of the Netherlands (16 million population) in a year was estimated at 187 and 52 for children and adults, respectively, so 239 in total. This is significantly lower than previous QMRA results on chicken fillet and drinking water consumption. Scenarios of 90% reduction of the contamination (meant to mimic cleaning) of all fences and just goat fences reduces the number of cases by 82% and 75%, respectively. The model can easily be adapted for other fecally transmitted pathogens.  相似文献   
239.
This article describes the evolution of the process for assessing the hazards of a geologic disposal system for radioactive waste and, similarly, nuclear power reactors, and the relationship of this process with other assessments of risk, particularly assessments of hazards from manufactured carcinogenic chemicals during use and disposal. This perspective reviews the common history of scientific concepts for risk assessment developed until the 1950s. Computational tools and techniques developed in the late 1950s and early 1960s to analyze the reliability of nuclear weapon delivery systems were adopted in the early 1970s for probabilistic risk assessment of nuclear power reactors, a technology for which behavior was unknown. In turn, these analyses became an important foundation for performance assessment of nuclear waste disposal in the late 1970s. The evaluation of risk to human health and the environment from chemical hazards is built on methods for assessing the dose response of radionuclides in the 1950s. Despite a shared background, however, societal events, often in the form of legislation, have affected the development path for risk assessment for human health, producing dissimilarities between these risk assessments and those for nuclear facilities. An important difference is the regulator's interest in accounting for uncertainty.  相似文献   
240.
This article draws on a 1 year ethnographic study of the process of teacher training from an inclusive position and that of general postgraduate training. Student teachers elected either to teach a given subject or to train in 'inclusive education' which aims to accommodate all learners, regardless of the notion of 'disability' or other forms of difference. The inclusive position challenges the notion of 'difference' and invites examination into how educational policy has the potential to enforce oppressive norms. The research reported here illustrates how socially constructed norms in relation to behavior and achievement are reproduced in the classroom. Ethnographic data demonstrates how educational philosophy is delivered to student teachers that supports either exclusive or inclusive strategies of teaching. The political environment that student teachers are immersed in is examined, together with documentation of the process of training and its inherent politics. Reflective points include how the political environment which teaching is delivered simultaneously creates and enforces dominant discourses of difference. Critical reflection on this research suggests that those involved in inclusive approaches to education need to be vigilant against the inclusive argument becoming a mantra.  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