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   19682篇
  免费   533篇
  国内免费   1篇
管理学   2911篇
民族学   74篇
人才学   2篇
人口学   1897篇
丛书文集   79篇
教育普及   3篇
理论方法论   1780篇
现状及发展   1篇
综合类   265篇
社会学   9586篇
统计学   3618篇
  2021年   113篇
  2020年   281篇
  2019年   383篇
  2018年   446篇
  2017年   612篇
  2016年   488篇
  2015年   363篇
  2014年   467篇
  2013年   3082篇
  2012年   647篇
  2011年   621篇
  2010年   458篇
  2009年   388篇
  2008年   472篇
  2007年   482篇
  2006年   469篇
  2005年   459篇
  2004年   423篇
  2003年   393篇
  2002年   434篇
  2001年   534篇
  2000年   539篇
  1999年   479篇
  1998年   352篇
  1997年   316篇
  1996年   328篇
  1995年   314篇
  1994年   287篇
  1993年   297篇
  1992年   357篇
  1991年   323篇
  1990年   292篇
  1989年   298篇
  1988年   294篇
  1987年   256篇
  1986年   254篇
  1985年   285篇
  1984年   273篇
  1983年   261篇
  1982年   223篇
  1981年   183篇
  1980年   173篇
  1979年   201篇
  1978年   187篇
  1977年   163篇
  1976年   141篇
  1975年   162篇
  1974年   121篇
  1973年   119篇
  1972年   95篇
排序方式: 共有10000条查询结果,搜索用时 93 毫秒
11.
12.
13.
Understanding the risk of biological invasions associated with particular transport pathways and source regions is critical for implementing effective biosecurity management. This may require both a model for physical connectedness between regions, and a measure of environmental similarity, so as to quantify the potential for a species to be transported from a given region and to survive at a destination region. We present an analysis of integrated biosecurity risk into Australia, based on flights and shipping data from each global geopolitical region, and an adaptation of the “range bagging” method to determine environmental matching between regions. Here, we describe global patterns of environmental matching and highlight those regions with many physical connections. We classify patterns of global invasion risk (high to low) into Australian states and territories. We validate our analysis by comparison with global presence data for 844 phytophagous insect pest species, and produce a list of high‐risk species not previously known to be present in Australia. We determined that, of the insect pest species used for validation, the species most likely to be present in Australia were those also present in geopolitical regions with high transport connectivity to Australia, and those regions that were geographically close, and had similar environments.  相似文献   
14.
Open innovation and absorptive capacity are two concepts based on the idea that companies can leverage the knowledge generated externally to improve their innovation performance. The aim of this paper is to analyse the joint effect of open innovation and absorptive capacity on a firm's radical innovation. Open innovation is expressed in terms of external search breadth and depth strategies and absorptive capacity is described by distinguishing between potential and realized absorptive capacity. In order to test our hypotheses, we carried out empirical research in firms operating in high-technology industries. The results indicate that internal routines and processes for absorbing external knowledge help explain radical innovation as they show a significant effect of potential and realized absorptive capacity. Also, there is a moderating effect of absorptive capacity on open innovation. Specifically, potential absorptive capacity exerts a positive effect on the relationship between external search breadth and depth and radical innovation. Realized absorptive capacity moderates the influence of external search breadth. These findings confirm the complementary nature of absorptive capacity and open innovation search strategies on radical innovation.  相似文献   
15.
Aggressive behavior in pet dogs is a serious problem for dog owners across the globe, with bite injuries representing a serious risk to both people and other dogs. The effective management of aggressive behavior in dogs represents a challenging and controversial issue. Although positive reinforcement training methods are now considered to be the most effective and humane technique to manage the risk of aggression, punishment‐based methods continue to be used. Unfortunately, there has been little scientific study into the various factors influencing whether dog owners choose to use positive reinforcement techniques to manage aggression in their dogs. As such, current understanding of how best to encourage and support dog owners to use these methods remains extremely limited. This article uses a survey methodology based on protection motivation theory (PMT) to investigate the factors that influence owner use of positive reinforcement methods to manage aggressive behavior, in an attempt to understand potential barriers and drivers of use. In addition, the article provides an initial exploration of the potential role of wider psychological factors, including owner emotional state, social influence, and cognitive bias. Findings show that the perceived efficacy of positive reinforcement methods and the perceived ability of owners to effectively implement the technique are both key factors predicting future intentions and current reported use. Future interventions should focus on enhancing owner confidence in the effective use of positive reinforcement techniques across multiple scenarios, as well as helping owners manage their own emotional responses when they encounter challenging situations and setbacks.  相似文献   
16.
17.
18.
Close to 20 percent of the Swedish population are of immigrant origin; one in eight is foreign‐born. About 45 percent of all immigrants originate from outside Europe and most of these have entered the country as refugees or relatives of refugees. Issues connected to immigration, including the number of immigrants, settlement patterns and level of social integration of ethnic minorities, have been much discussed in Sweden in recent decades. This paper focuses on the integration of Latin American immigrants in Sweden. It compares the level of integration – measured as educational achievement, labour market participation, income and housing – experienced by first and second generation migrants. I use register information allowing me to include all 1st and 2nd generation Latin Americans that have lived in Sweden between 1990 and 2006 (in total 127,000 individuals). Data are longitudinal, which means that individuals can be followed over time. I make use of the longitudinal material in order to study changes in residential patterns and in attempts to explain educational and employment outcomes for second generation Latin Americans. The general conclusion of the paper is that in terms of integration, LAC immigrants have an intermediate position compared to other immigrant categories; they are often better off than people from Africa and the Middle East but clearly below the level experienced by some other migrants, especially those from Western Europe. This cannot be explained by level of education. The average level of education is high for first generation immigrants from LA countries. For many people, the level of labour market participation and income increase over time but one important result of this analysis is that second generation Latin Americans seem to do less well in Sweden compared to many other second generation migrants.  相似文献   
19.
20.
Journal of Population Research - This paper details efforts to link administrative records from the Internal Revenue Service (IRS) to American Community Survey (ACS) and 2010 Census microdata for...  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