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   458篇
  免费   23篇
  481篇
  2023年   2篇
  2020年   6篇
  2019年   10篇
  2018年   11篇
  2017年   16篇
  2016年   18篇
  2015年   15篇
  2014年   13篇
  2013年   171篇
  2012年   15篇
  2011年   19篇
  2010年   15篇
  2009年   10篇
  2008年   11篇
  2007年   7篇
  2006年   12篇
  2005年   6篇
  2004年   10篇
  2003年   4篇
  2002年   3篇
  2001年   3篇
  2000年   8篇
  1999年   9篇
  1998年   4篇
  1997年   6篇
  1995年   4篇
  1994年   2篇
  1993年   5篇
  1992年   2篇
  1990年   2篇
  1989年   4篇
  1988年   6篇
  1987年   5篇
  1986年   3篇
  1985年   6篇
  1984年   5篇
  1982年   3篇
  1980年   4篇
  1978年   2篇
  1977年   1篇
  1976年   2篇
  1975年   1篇
  1974年   2篇
  1973年   2篇
  1972年   2篇
  1971年   4篇
  1970年   1篇
  1969年   1篇
  1968年   1篇
  1954年   1篇
排序方式: 共有481条查询结果,搜索用时 0 毫秒
1.
2.
3.
4.
5.
This paper is concerned with the reciprocal relationship between migration and development in Third World settings. Using individual-level data for Venezuela, migration behavior is related to a person's age, educational attainment, gender, and characteristics of his/her place(s) of residence as an out-migrant, in-migrant, or stayer. Place characteristics are in terms of four groups based on employment patterns: the core, regional centers, resource frontiers, and traditional rural areas. Four questions are of concern. First, does development influence migration? All analyses indicate this is so. Second, does migration influence development? Findings are ambiguous in that places experiencing improvement in their mix of human capital lagged in the net number of persons obtained through migration whereas a gain in numbers was accompanied by deterioriation in human capital profiles. Third, was incipient polarization reversal occurring in Venezuela in the late 1960s, early 1970s? This paper departs from the usual approach by addressing this question in terms of human capital attributes instead of population aggregates. On this basis, polarization reversal is in evidence, particularly in regional centers. Finally, this study answers in the affirmative that places with different development characteristics generate migration streams differing in type, magnitude, explanation, and impact.  相似文献   
6.
The need for experiments to study physical aspects of craft of the past is stated, as well as the necessity for them to have clear aims and to follow the established principles of scientific enquiry. These principles are discussed in this joint paper by ten maritime archaeologists and others, together with methods and some points of management critical to their application in this field.  相似文献   
7.
Participants in a statewide family preservation program were classified on the basis of income level and enrollment in public assistance. These variables, along with other economic, parent, and child risk factors, were used to predict the probability of out-of-home placements at the close of this intervention program. Results revealed that neither low income nor receiving public assistance was predictive of having a child removed from the home. Higher levels of child-centered risk and parent-centered risk were the only consistent predictors of placement outcomes. Additional analyses revealed that family characteristics (e.g., history of psychiatric care, prior child placements, and involvement with the legal system) also were typical of families experiencing out-of-home placements. This study challenges the stereotype of low-income or welfare families being at greater risk of having a child removed from their home. Findings are discussed in the context of recent welfare reform initiatives and implications for future family policy research.  相似文献   
8.
9.
10.
Methodological advancements in geoarchaeology and spatial and chronological modeling are opening new avenues to interpreting large coastal shell-bearing sites. We document the developmental histories of two such sites around Prince Rupert Harbour, Canada, using systematic percussion coring, intensive radiocarbon dating, and 3D surface mapping with Total Station and LiDAR. We also re-analyze a third site (Boardwalk/GbTo-31) excavated and radiocarbon dated in the 1960s, 1970s, and early 2000s using archival field notes, site maps, and stratigraphic profiles georectified using LiDAR. We map the natural landform beneath the sites and document the degree to which people physically modified landforms through the deposition of massive shell accumulations. We model site development through time and space and use accumulation rates and OxCal modeling to test for intentional deposition events. All three sites demonstrate complex and heterogeneous occupation histories. At each we identify instances of very rapid deposition that effectively terraced and extended parts of the natural landform to create places for constructing houses, though these episodes take place within longer histories of slower quotidian deposition. The anthropogenic modifications to the coastline in this area are the result of these mixed processes associated with long histories of occupation.  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