全文获取类型
收费全文 | 516篇 |
免费 | 15篇 |
专业分类
531篇 |
出版年
2021年 | 2篇 |
2020年 | 9篇 |
2019年 | 16篇 |
2018年 | 16篇 |
2017年 | 25篇 |
2016年 | 21篇 |
2015年 | 7篇 |
2014年 | 12篇 |
2013年 | 202篇 |
2012年 | 9篇 |
2011年 | 7篇 |
2009年 | 7篇 |
2008年 | 12篇 |
2007年 | 4篇 |
2006年 | 9篇 |
2005年 | 6篇 |
2004年 | 9篇 |
2003年 | 4篇 |
2002年 | 3篇 |
2001年 | 4篇 |
2000年 | 3篇 |
1999年 | 5篇 |
1998年 | 5篇 |
1997年 | 5篇 |
1996年 | 2篇 |
1995年 | 6篇 |
1994年 | 4篇 |
1993年 | 6篇 |
1992年 | 3篇 |
1991年 | 6篇 |
1990年 | 8篇 |
1989年 | 6篇 |
1988年 | 2篇 |
1987年 | 4篇 |
1986年 | 2篇 |
1985年 | 8篇 |
1984年 | 6篇 |
1983年 | 6篇 |
1982年 | 6篇 |
1981年 | 8篇 |
1980年 | 5篇 |
1979年 | 4篇 |
1978年 | 5篇 |
1977年 | 4篇 |
1976年 | 9篇 |
1975年 | 2篇 |
1974年 | 4篇 |
1973年 | 2篇 |
1969年 | 2篇 |
1968年 | 2篇 |
排序方式: 共有531条查询结果,搜索用时 0 毫秒
61.
COLLEGE-TO-WORK MIGRATION OF TECHNOLOGY GRADUATES AND HOLDERS OF DOCTORATES WITHIN THE UNITED STATES 总被引:2,自引:0,他引:2
ABSTRACT. This study estimates a series of random parameter logit models of the college-to-work migration decisions of technology graduates and holders of doctorates within the United States. We employ detailed information on the migration-relevant characteristics of individuals, as well as on their actual origins and destinations at the metropolitan scale. In addition to its obvious implications for "brain drain" policies in U.S. metropolitan areas, the study demonstrates the richness of the random parameters technique for behavioral-geographic analysis. We find that science and technology graduates migrate to better educated places, other things equal; that PhD graduates pay greater attention to amenity characteristics than other degree holders; and that foreign students from some immigrant groups migrate to places where those groups are concentrated. 相似文献
62.
In Canada and elsewhere, there is a growing belief that farming and rural communities have become effectively disconnected from one another. While attention to recent media reporting suggests that incidences of conflict are now as common as examples of support and collaboration, it is suggested that many examples of complementarity remain. These evolving relationships may, however, be linked to the nature of specific farm development trajectories. Such possibilities warrant empirical examination, with attention to known diversity in the family farm sector. This paper reports on an empirical investigation of farm and community linkages in North Huron County, Ontario. The paper builds upon a recent investigation of change in family farming in this region and seeks to document the ways in which local farmers continue to look to their rural communities for support of various kinds. Data are drawn from a survey of farmers in Ashfield and Colborne Townships in 1999. The research explores community linkages around three dominant themes: participation in organisations, purchasing and perceptions and experiences of community support for farming. The findings indicate the persistence of strong linkages between farms and local communities in the study region but point to a potential tendency for disconnection between farms pursuing aggressive expansion and local community organisations and businesses. There is some evidence that jobs and a variety of farm household considerations may form key linkage points between the two sectors, with the importance of these mediated by farm business trajectories and the family life course. 相似文献
63.
64.
David R. Braun Thomas Plummer Peter Ditchfield Joseph V. Ferraro David Maina Laura C. Bishop Richard Potts 《Journal of archaeological science》2008
The archaeological record of Oldowan hominins represents a diverse behavioral system. It has been suggested that exploitation of lithic resources by Oldowan hominins was simplistic and represented mostly use of local sources of stone. Here we investigate the raw material selection and transport behaviors of Oldowan hominins reflected in the stone artifact assemblages from the Kanjera South Formation, South Rachuonyo District, Kenya. Using geochemical methods (ED-XRF) artifacts are linked to primary and secondary source outcrops throughout southwestern Kenya. These data show that hominins selected raw materials for transport at frequencies that are significantly different from their availability on ancient landscapes. Furthermore, a substantial proportion of the assemblage represents transport over relatively long distances (>10 km). Our study further suggests that in the early stages of stone tool use hominins used a wide variety of raw materials and selected these materials at some distance from their eventual discard locations. Early hominin behavior may have incorporated an understanding of raw material source distributions across a more extensive landscape than has been previously documented. This supports the growing perspective that Oldowan technology represents a more complex behavioral pattern than is usually associated with the beginnings of hominin tool use. 相似文献
65.
66.
67.
Joseph A. Rodriguez 《对极》1999,31(2):212-228
Regional transportation planning shaped minority activism in the mid-1960s. The Bay Area Rapid Transit (BART) system encouraged West Oakland activists to create a strong local identity. BART supporters valued regional mobility and blamed ghetto poverty on the inaccessibility of suburban jobs. Minority activists blamed BART for harming the ghetto poor by encouraging job migration to the suburbs, and for displacing residents. As compensation, they demanded that BART hire minority workers and increase relocation payments. While West Oakland activists largely failed to influence BART, the newly unified community did gain local control of schools and urban poverty programs. 相似文献
68.
69.
Abstract. In this paper, we extend the partial equilibrium urban model of DeSalvo (1985) to include mode choice. DeSalvo demonstrated that the urban model of Muth (1969) was robust to the extension to leisure choice. We show that the model is robust to mode choice as well. In addition, we derive the comparative static results that commuters choose higher speed modes for longer commutes, at higher wage rates, with greater tastes for housing, and with lower housing prices. Also, for a given distance commuted, we derive the comparative static result that commuters chose shorter duration commutes at higher wage rates. Whereas it is typically assumed that marginal commuting cost is positive and non‐increasing with distance, we derive these results. Moreover, we derive the results that marginal commuting cost rises with an exogenous increase in housing price and falls with increased tastes for housing. We also explore the effects of exogenous commuting‐cost changes on the endogenous variables of the model. The remaining comparative static results on housing consumption and location are qualitatively the same as in DeSalvo. 相似文献
70.
Joseph Fracchia 《History and theory》2003,42(3):378-397
Book reviewed in this article:
Allan Megill, Karl Marx: The Burden of Reason (Why Marx Rejected Politics and The Market) 相似文献
Allan Megill, Karl Marx: The Burden of Reason (Why Marx Rejected Politics and The Market) 相似文献