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   139篇
  免费   6篇
管理学   14篇
民族学   1篇
人口学   9篇
理论方法论   18篇
综合类   1篇
社会学   95篇
统计学   7篇
  2023年   4篇
  2022年   1篇
  2021年   3篇
  2020年   5篇
  2019年   1篇
  2018年   9篇
  2017年   9篇
  2016年   8篇
  2015年   2篇
  2014年   4篇
  2013年   25篇
  2012年   2篇
  2011年   1篇
  2010年   2篇
  2009年   4篇
  2008年   6篇
  2007年   3篇
  2006年   5篇
  2005年   4篇
  2004年   4篇
  2003年   4篇
  2002年   4篇
  2001年   3篇
  2000年   7篇
  1999年   3篇
  1998年   2篇
  1997年   1篇
  1996年   1篇
  1995年   1篇
  1994年   2篇
  1993年   1篇
  1990年   2篇
  1989年   1篇
  1988年   1篇
  1986年   3篇
  1985年   1篇
  1981年   1篇
  1980年   1篇
  1978年   1篇
  1977年   1篇
  1973年   1篇
  1970年   1篇
排序方式: 共有145条查询结果,搜索用时 218 毫秒
81.
Bringing innovations to market is critical to industrial progress and economic growth. We explore the potential for information technology (IT) to enable innovations, and thus improve productivity. We hypothesize that a knowledge stock of process‐oriented research and development (R&D) increases total factor productivity growth by leveraging traditional forms of capital and labor, and further enhances the ability of IT capital to increase productivity. We estimate these relationships using two broad panels of U.S. industries covering the periods 1987–1998 and 1998–2005. The results indicate qualified support for a synergistic effect of R&D and IT investment in both periods.  相似文献   
82.
The study of quality of life remains a key area of interest for not only researchers but to society. Through research being completed in multiple disclines and from a multitude of perspectives, the need to understand the full breadth of quality of life is required in order for the further development of this research area. Through building on previous research completed on quality of life from multiple disclines, this study utilizes numerous objective and subjective indicators to model quality of life in a community in the southwest United States. Through the analysis of 352 completed surveys, it was found that the two strongest predictors of quality of life were community pride and community elements. Of interest is that a number of other indicators including recreation participation and length of residency in a community were found to have a negative relationship with quality of life.  相似文献   
83.
The authors used social marketing to design and test advertisement components aimed at increasing students' interest in attending an alcohol program focused on reaching students who drink heavily, although the authors offered no such program. Participants were undergraduate students in introductory psychology courses (N = 551). Questionnaires included measures assessing demographic information, alcohol use and negative consequences, and interest in attending an alcohol program in response to exposure to 1 of 12 systematically varied advertisements. The authors found that approximately 20% of participants across all ad types indicated some level of interest in attending the alcohol program. Students who use alcohol reported more interest in attending when an informational message was used. Of the participants offered food, 41.9% indicated the food offered in the advertisement impacted their interest in attending. Results suggest market segmentation plays a role in developing effective advertisements to recruit different groups of students based on their reported drinking behavior.  相似文献   
84.
In 2015 the International Organization for Migration (IOM) identified almost 1,200 trafficked migrants working in slave‐like conditions on fishing boats in East Indonesia. The IOM helped the migrants and offered to cover the cost of repatriation to their countries of citizenship. The Indonesian government appreciated the financial support, not least because the victims’ embassies refused to pay. But most victims in one location refused to return to their home country without the wages owed to them by their trafficker‐cum‐employers. IOM policy states that migrants are eligible to use the Assisted Voluntary Return and Reintegration (AVRR) service if they are unable or unwilling to remain in the host country. But another condition is that migrants must use the services voluntarily. The IOM could not force the migrants to leave the country, and national law prevented the Indonesian government from deporting the migrants because the IOM had identified them as victims of trafficking. 1  相似文献   
85.
86.
Picture books often play an important role in childhood socialization. Given the seriousness of environmental problems, we ask how natural, modified, and built environments have been portrayed in children’s books. To answer this question, we analyze the 296 books receiving Caldecott awards from 1938 to 2008. Two possibilities are explored with respect to content change. Growing concern about critical environmental problems, such as decline in biodiversity and deforestation, may have led to an increase in illustrations and stories about wild animals and the natural environment. Alternatively, the increasing isolation of people from the natural world may have resulted in a decline in the perceived relevance of these environmental issues and resulted in fewer stories and depictions. Our findings support the isolation hypothesis. There have been significant declines in depictions of natural environments and animals while built environments have become much more common. These findings suggest that today’s generation of children are not being socialized, at least through this source, toward an understanding and appreciation of the natural world and the place of humans within it.  相似文献   
87.
Urban forests provide important environmental benefits, leading many municipal governments to initiate citywide tree plantings. However, nutrient cycling in urban ecosystems is difficult to predict, and nitrogen (N) use in urban trees may be quite different from use in rural forests. To gain insight into these biogeochemical and physiological processes, we compared foliar N characteristics of several common northeastern deciduous tree species across four newly planted New York City afforestation sites as well as at the Black Rock Forest (BRF), a rural oak-dominated forest in the Hudson Highlands, New York. Foliage sampled at BRF was consistently depleted in 15N compared to urban foliage, and Amelanchier canadensis, Nyssa sylvatica, Prunus serotina, and Quercus rubra showed significant variation in foliar nitrogen isotope signatures (δ15N) among the four urban sites. A. canadensis and P. serotina showed significantly greater ability to assimilate nitrate at BRF compared to urban sites, as measured through nitrate reductase activity (NRA). There were no significant differences in NRA among tree species growing at the four urban sites. Only P. serotina and N. sylvatica showed significant variation in foliar N concentrations (%N) both among urban sites and compared to BRF. The isotopic and %N data suggest greater N availability but less available nitrate at the newly planted urban sites compared to BRF, possibly due to different anthropogenic inputs or higher rates of nitrification and nitrate leaching at the recently planted urban sites compared to likely lower rates of N cycling in the intact rural forest. In addition, the tree species varied in their response to N availability at the urban sites, with potential implications for growth and survival. Understanding N cycling in urban systems and the associated physiological changes in vegetation is critical to a comprehensive evaluation of urban forest restoration, and may have implications for carbon sequestration and water quality issues associated with nitrate export, two important areas of management concern.  相似文献   
88.
This study examined adolescents’ concerns about social issues and how these concerns have changed over historical time. Separate cohorts of U.S. high school seniors (= 110,953; 51.1% female) reported their worries about four social issues (crime/violence, economic problems, hunger/poverty, race relations) every year from 1976 to 2015. Youth were most concerned with crime/violence, followed by economic problems, hunger/poverty, and race relations. Adolescents’ social concerns varied by demographic characteristics and cohort, paralleling specific historical events and appearing responsive to the political challenges of the time. Initiatives seeking to engage youth within the political process may benefit from providing opportunities for teens to participate in civic activities aimed to address these issues.  相似文献   
89.
Task clarification in the form of workplace policy guidelines coupled with weekly graphic feedback of group punch-in times on the staff clock were presented to waitstaff, cooks, cash register clerks, dishwashers, buffet attendants, and hourly assistant managers in a restaurant sub-franchise. Clocking in early dropped from 130 min during baseline to 62 min per week during intervention. A 1-week return to baseline resulted in 189 min of clocking in early by restaurant personnel. The use of task clarification and group feedback reduced company expenses without reductions in job satisfaction or increased stress.  相似文献   
90.
Adaptive emotion regulation (ER) in parents has been linked to better parenting quality and social–emotional adjustment in children from middle‐income families. In particular, early childhood may represent a sensitive period in which parenting behaviors and functioning have large effects on child social–emotional adjustment. However, little is known about how parent ER and parenting are related to child adjustment in high‐risk families. In the context of adversity, parents may struggle to maintain positive parenting behaviors and adaptive self‐regulation strategies which could jeopardize their children's adjustment. The current study investigated parents' own cognitive ER strategies and observed parenting quality in relation to young children's internalizing and externalizing problems among families experiencing homelessness. Participants included 108 primary caregivers and their 4–6‐year‐old children residing in emergency shelters. Using multiple methods, parenting and parent ER were assessed during a shelter stay and teachers subsequently provided ratings of children's internalizing and externalizing difficulties in the classroom. Parenting quality was expected to predict fewer classroom internalizing and externalizing behaviors as well as moderate the association between parent ER strategies and child outcomes. Results suggest that parenting quality buffered the effects of parent maladaptive ER strategies on child internalizing symptoms. The mediating role of parenting quality on that association was also investigated to build on prior empirical work in low‐risk samples. Parenting quality did not show expected mediating effects. Findings suggest that parents experiencing homelessness who use fewer maladaptive cognitive ER strategies and more positive parenting behaviors may protect their children against internalizing problems.  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