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   805篇
  免费   41篇
管理学   55篇
民族学   9篇
人口学   76篇
丛书文集   18篇
理论方法论   164篇
综合类   71篇
社会学   268篇
统计学   185篇
  2024年   2篇
  2023年   12篇
  2022年   3篇
  2021年   4篇
  2020年   19篇
  2019年   27篇
  2018年   46篇
  2017年   55篇
  2016年   34篇
  2015年   29篇
  2014年   42篇
  2013年   134篇
  2012年   68篇
  2011年   32篇
  2010年   39篇
  2009年   53篇
  2008年   57篇
  2007年   19篇
  2006年   26篇
  2005年   20篇
  2004年   19篇
  2003年   17篇
  2002年   11篇
  2001年   5篇
  2000年   8篇
  1999年   10篇
  1998年   2篇
  1997年   7篇
  1996年   3篇
  1995年   4篇
  1994年   5篇
  1993年   3篇
  1992年   5篇
  1991年   6篇
  1990年   1篇
  1989年   2篇
  1987年   3篇
  1986年   3篇
  1984年   3篇
  1983年   2篇
  1982年   2篇
  1977年   1篇
  1976年   1篇
  1971年   1篇
  1969年   1篇
排序方式: 共有846条查询结果,搜索用时 15 毫秒
41.
The restructuring of production resulting from the Port Modernization Law (Law 8.630/90) caused significant changes in work organization of Brazilian Ports. In the case of Mucuripe (Fortaleza, Ceará), in particular, the changes were very intense as Mucuripe is an old port that, before the Law, had labor regulation being governed by Trade Unions. This paper aims to present the perceptions of Union Representatives on the changes brought about by the Law on work organization in the port of Fortaleza, its influence in the organization and in the way the Unions deal with this new reality. Open and exploratory interviews were conducted with representatives of occasional labor workers registered in the Port of Fortaleza OGMO (Org?o Gestor de M?o de Obra, Labor Regulation Management). The analysis of the collected material in the interviews was based on the technique of content analysis proposed by Bardin (1979). Trade Unions have undergone a great loss of power and it has reflected in a relative inability to perform its function and to fight for the rights of the workers. The obvious Trade Unions weakness - a reduction of strikes and less unionized workers - reflects the dominating ideology of capital.  相似文献   
42.
Augmented Reality focuses on the enrichment of the user's natural field of view by consistent integration of text, symbols and interactive three-dimensional objects in real time. Placing virtual objects directly into the user's view in a natural context empowers highly dynamic applications. On the other hand, this necessitates deliberate choice of information design and density, in particular for deployment in hazardous environments like military combat scenarios. As the amount of information needed is not foreseeable and strongly depends on the individual mission, an appropriate system must offer adequate adaptation capabilities. The paper presents a prototypical, vehicle-mountable Augmented Reality vision system, designed for enhancing situation awareness in stressful urban warfare scenarios. Tracking, as one of the most crucial challenges for outdoor Augmented Reality, is accomplished by means of a Differential-GPS approach while the type of display to attach can be modified, ranging from ocular displays to standard LCD mini-screens. The overall concept also includes envisioning of own troops (blue forces), for which a multi-sensor tracking approach has been chosen. As a main feature, the system allows switching between different information categories, focusing on friendly, hostile, unidentified or neutral data. Results of an empirical study on the superiority of an in-view navigation cue approach conclude the paper.  相似文献   
43.
In the areas of design, especially in architectural design, collaboration has become an important challenge. The specialization of skills increase, work teams are more and more extensive and the geographic distance between them increases too. The economic and ecological stakes related to remote collaboration are an evidence. This context involves the need to support most efficiently possible remote working meetings. We present the Distributed Collaborative Digital Studio (DSDC), a tool designed to recreate, in distant situations, the context of copresence meetings. This shared environment is created in the "invisible computer" approach [11]. The idea is that the tool should disappear from user's consciousness. Indeed, creative design activities require some fluidity in their process. Therefore, any involuntary interruption created by the system can potentially brake creativity. In this perspective, we investigate specifically the "invisibility" of our environment. To do this, we propose a framework for the operationalization of the concept and a methodology to test the system invisibility. This methodology was applied through a case study consisting of a corpus of 12 hours of remote collaborative design sessions with the DSDC. We highlight the learning effects while using our system, conclude on its effectiveness and discuss our methodology.  相似文献   
44.
This research aimed to study the activity of the HLB's scouts, workers whose function is to identify symptomatic plants, in order to understand the physical constraints, cognitive and organizational involved in accomplishing the task, characterizing the operative approach used to identify diseased plants, and to elucidate what aspects hinder the identification of symptoms. The method adopted for the research was the Ergonomic Analysis of Work--EAW [6]. The results, after validation with the operators and management, allowed understanding the complex relationships between the physical, cognitive and organizational aspects present on activity. Major difficulties were observed mainly in relation to the disposal of the scouts on the platforms and in relation to working hours, at the beginning and end of the journey. Important findings have highlighted strategies, unknown by the organization, used by scouts to locate candidates' trees to the fine analysis of investigation of symptoms. In conclusion, the analysis enable to understand the constraints and find technical and organizational solutions to the survey work on citrus groves as well as it showed signs and symptoms not investigated yet or rarely considered by researchers involved on searches aimed at increasing the ability to diagnose the disease in the field.  相似文献   
45.
The use of a thermal buttocks manikin was explored as a tool to standardize the evaluation of seat comfort. Thermal manikin buttocks were developed and calibrated thermally and anatomically to simulate the sensible heat transfer of a seated person and used to evaluate interface pressure distribution. In essence, the pressure maps of manikin buttocks with and without heating were compared to those of a seated person. The results of average pressure demonstrated that the thermal manikins have a better response in interface pressure measurement than manikins without heating.  相似文献   
46.
It is widely recognised that ergonomists must contribute during needs analysis. However, few studies have investigated the specific contributions of ergonomists at this stage of the design process. In this study, this contribution is studied through the requirement document produced by the design team. For each requirement, the source (i.e. who formulated the requirement), justification (why the requirement is needed), type (functional, interaction, operational, physical, organizational), and scope (entire system or part thereof) were analysed. Results indicate that the various actors are complementary and work collectively to define the various dimensions of the system. With end-users, the ergonomist worked on the global aspects of the system: function, conditions of use and organizational dimension. Alone, he defined the global interaction of the system. The various functions derived from the global function were defined in collaboration with engineers. However, while engineers contributed to defining how these functions would work, as well as their technical conditions of use, the ergonomist focused on their purpose, and, with end-users, on their organizational aspects. Finally, results suggest that neither the ergonomist's specific knowledge in ergonomics, nor work analysis were sufficient to derive his requirements; both are mandatory.  相似文献   
47.
48.
49.
Due to habitat fragmentation, resource disruption and pollution, urbanization is one of the most destructive forms of anthropization affecting ecosystems worldwide. Generally, human-mediated perturbations dramatically alter species diversity in urban sites compared to the surroundings, thus influencing the functioning of the entire ecosystem. We investigated the taxonomic and functional diversity patterns of the aquatic macroinvertebrate communities in tank bromeliads by comparing those found in a small Neotropical city with those from an adjacent rural site. Changes in the quality of detrital inputs in relation to lower tree diversity and the presence of synanthropic species are likely important driving forces behind the observed structural changes in the urban site. Leaf-litter processors (i.e., shredders, scrapers) were positively affected in the urban site, while filter-feeders that process smaller particles produced by the activity of the shredders were negatively affected. Because we cannot ascertain whether the decline in filter-feeders is related to food web-mediated effects or to competitive exclusion (Aedes aegypti mosquitoes were present in urban bromeliads only), further studies are necessary to account for the effects of intra-guild competition or inter-guild facilitation.  相似文献   
50.
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