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   19810篇
  免费   400篇
  国内免费   1篇
管理学   2607篇
民族学   111篇
人口学   1744篇
丛书文集   75篇
教育普及   1篇
理论方法论   1764篇
综合类   185篇
社会学   9954篇
统计学   3770篇
  2023年   132篇
  2022年   91篇
  2021年   135篇
  2020年   348篇
  2019年   515篇
  2018年   611篇
  2017年   795篇
  2016年   611篇
  2015年   410篇
  2014年   574篇
  2013年   3530篇
  2012年   737篇
  2011年   683篇
  2010年   502篇
  2009年   404篇
  2008年   532篇
  2007年   486篇
  2006年   525篇
  2005年   410篇
  2004年   421篇
  2003年   353篇
  2002年   364篇
  2001年   471篇
  2000年   412篇
  1999年   405篇
  1998年   312篇
  1997年   261篇
  1996年   278篇
  1995年   288篇
  1994年   246篇
  1993年   256篇
  1992年   301篇
  1991年   297篇
  1990年   290篇
  1989年   254篇
  1988年   240篇
  1987年   204篇
  1986年   229篇
  1985年   250篇
  1984年   218篇
  1983年   191篇
  1982年   159篇
  1981年   130篇
  1980年   156篇
  1979年   173篇
  1978年   134篇
  1977年   114篇
  1976年   89篇
  1975年   94篇
  1974年   95篇
排序方式: 共有10000条查询结果,搜索用时 12 毫秒
991.
This work is based on the study of pioneering sustainable product development initiatives, and the analysis was guided by the cradle-to-cradle concept, which sees the waste of a given process as raw material for another, just like it happens in nature. Several studies on human factors have focused on factory conditions and workers dealing with product assembly. This research, however, relates more to consumer behavior, product use and end-of-life. The purchase of more environmentally- friendly products, in particular, is heavily influenced by the information made available by the companies. In this scenario, this article discusses three early but notable efforts on green product development, focusing on the disclosure practices adopted by the companies regarding the composition of their products. Research and data collection has focused on the footwear industry, whose products satisfy a basic human need and are ubiquitous worldwide. The use of hazardous materials and chemicals in shoe manufacturing, particularly the use of chromium - a highly toxic element - in addition to toxic solvents and adhesives and non-recyclable synthetic materials can pose serious risks to human health and the environment, even though the consumer usually is not aware of all the relevant characteristics of this kind of product.  相似文献   
992.
Research activities to determine the need of recovery time at work were mainly performed in the 1970s and 1980s. Previous studies were largely based on expert opinions or were generated within small and non-representative groups. Often, laboratory experiments were carried out with a low number of subjects. Especially during the last decade, only little additional scientific knowledge was generated on this topic. The very resource intensive development of more detailed results based on the existing level of scientific knowledge is assumed as one reason for this. In general, it seems to be reasonable to continue further research on the knowledge generated in previous studies, but implement larger samples and more representative groups. Besides, according to monotonous manual work, more research is especially needed regarding relative operating forces and operation frequencies taken grip conditions and hand/body position into account.  相似文献   
993.
This study aims to describe how anesthesia teams handle unforeseen events that may affect the patients' health. More precisely, it investigates the mechanisms of decisions made by anesthesia teams to manage unthought-of situations, i.e. situations that have not been foreseen as "possible" ones before their occurrence. An empirical study, based on the analysis of simulated situations, was conducted in a pediatric anesthesia service of a university hospital in France. The results highlighted three ways of managing unthought-of situations (determined management, cautious management and overwhelmed management). They support the hypothesis of a collective cognitive trade-off, whereby teams would behave as virtual operators, with their own collective trade-off between "understanding" and "doing". The discussion of the results questions the assessment criteria, the safety perspectives we adopt and the possible ways to improve the management of unforeseen situations.  相似文献   
994.
995.
Gerontolinguistic obtains a growing importance with the increase of elderly users due to Demographic Change. Since acceptance and ease of use of supportive systems for elderly, such as "E-Nursing-Assistants", are highly dependent on the age suitable design of readable instructions, an age-appropriate linguistic concept is of high value for usability. There has been only little research on the relevance of foreign words, signal words, textual arrangement, optical accentuation of key terms and temporal iconicity concerning older users. Thus, an efficient design of age suitable manual instructions within a medical context still remains to be done. The objective of this research was to evaluate the relevance of the previously mentioned factors in the context of written instructions. For this, an empirical survey was designed which was given to 45 study participants. The subjects of the experiment were given 4x3 instructions after a pretest questionnaire. The aim was to execute these instructions as correctly and quickly as possible. Furthermore the instructions were rated regarding comprehensibility with a retrospective questionnaire.  相似文献   
996.
This study presents the challenge involved in the negotiation and construction of a standard process in a major petroleum company that has the purpose of guiding the implementation of ergonomic studies in the development of projects, systemising the implementation of ergonomics design. The standard was created by a multi-disciplinary working group consisting of specialists in ergonomics, who work in a number of different areas of the company. The objective was to guide "how to" undertake ergonomics in all projects, taking into consideration the development of the ergonomic appraisals of work. It also established that all the process, in each project phase, should be accompanied by a specialist in ergonomics. This process as an innovation in the conception of projects in this company, signals a change of culture, and, for this reason requires broad dissemination throughout the several company leadership levels, and training of professionals in projects of ergonomics design. An implementation plan was also prepared and approved by the corporate governance, complementing the proposed challenge. In this way, this major oil company will implement new procedures of ergonomics design to promote health, safety, and wellbeing of the workforce, besides improving the performance and reliability of its systems and processes.  相似文献   
997.
Comfort is an issue that has gained relevance within the aeronautical industry due to the necessity of manufacturers and airline companies of differentiating themselves in a market that has become more and more competitive each day. This study's aim is to analyze the comfort/discomfort of passengers, based on the analysis of the activities performed in the aircrafts' cabin during real flights, in order to create ergonomics requirements and a methodology of comfort analysis. The study has been performed during domestic commercial flights, and the adopted data collection techniques have been: the application of 219 questionnaires to passengers, 44 registrations of postures and actions through filmings and 12 semistructured interviews. The method has made possible the reconstruction of the user's action course in performing activities in real flight situations, and the calculation of the area occupied by the passenger during his or her actions. The integrated analysis of the results corroborates data from previous studies in which both the space made available to each passenger and the activity performed interfere in their perception of comfort. From this study it has been concluded that the method constitutes itself as an innovative tool within the process of aircrafts' cabins project enabling the calculation of the action space based on the reconstructed course.  相似文献   
998.
Japan is famous for long working hours. For decades the Japanese government has tried to influence how people spend their free time. In 5-yearly surveys since 1986 the government has surveyed ??quality of life,?? gauging how much time people spend daily in various activities, including ??leisure.?? Analyzing results from these time use surveys, from 2006 back to 1986, and controlling for labor market conditions, this study determines whether time spent on leisure activities has actually changed. Gains in some types of leisure have been fleeting. Yet in other respects leisure has been enhanced, with significant increases occurring in active recreational pastimes. Nevertheless, leisure remains elusive for mid-career employees. Moreover, there is a pronounced gender gap for leisure time.  相似文献   
999.
Research regarding lesbian mothers and their children has gone through a transformation in the last forty years. The first wave of research examined lesbians who had become parents while in heterosexual relationships. The second wave examined women who became parents within the context of lesbian relationships. Both of these waves focused on family functioning and child outcome, using heterosexual-headed families as comparison groups. The third wave of research, which is now underway, is focusing on the unique challenges faced by these families, and how lesbian mothers are creating and raising their families on their own terms. This article explores the research as it has evolved over the years and the direction in which it is headed.  相似文献   
1000.
Improving our understanding of the impacts of urbanization on tropical island streams is critical as urbanization becomes a dominant feature in tropical areas. Although the ??urban stream syndrome?? has been successful in summarizing urban impacts on streams, the response of some island streams is different to that expected. Here we review available information on urban impacts to tropical island streams and describe unique responses to urbanization. We identified three key aspects that play particularly important or unique roles in determining tropical-island stream integrity: biotic response to water pollution, movement barriers along the stream network, and altered geomorphology that results in habitat loss. As expected, water pollution negatively impacts stream ecosystems in tropical islands and in some regions impacts can be severe, as untreated wastewaters are directly discharged into streams. While aquatic insects show the expected responses to pollution, other native fauna (e.g., shrimps and fishes) appear to be less impacted by moderate levels of pollution. Movement barriers along the stream network are especially important as much of the tropical island fauna have diadromous (either amphidromous or catadromous) life histories. Most native freshwater mollusks, shrimps, and fishes inhabiting tropical islands are diadromous and depend on unimpeded connections between freshwater and marine environments to complete their life cycles. The presence of these species in urban streams is best explained by longitudinal connectivity rather than by the degree of urban impact. Finally, in streams that remain connected to marine environments, the presence of native shrimps and fishes is strongly related to the physical habitat. Fish assemblages in channelized and severely altered stream reaches are almost completely devoid of native fauna and tend to be dominated by non-native species. In contrast, relatively diverse shrimp and fish assemblages can be found in reaches that retain their physical habitat complexity, even when they are impacted by urbanization. Our understanding of urban impacts on tropical island streams remains limited. However, the identification of key aspects can help us better understand urban impacts on streams in tropical islands, and best focus our management and research efforts to protect these unique ecosystems.  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