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   12925篇
  免费   576篇
  2023年   83篇
  2020年   213篇
  2019年   287篇
  2018年   648篇
  2017年   563篇
  2016年   672篇
  2015年   322篇
  2014年   312篇
  2013年   3264篇
  2012年   387篇
  2011年   528篇
  2010年   550篇
  2009年   366篇
  2008年   359篇
  2007年   409篇
  2006年   251篇
  2005年   197篇
  2004年   151篇
  2003年   149篇
  2002年   159篇
  2001年   203篇
  2000年   163篇
  1999年   182篇
  1998年   136篇
  1997年   115篇
  1996年   112篇
  1995年   113篇
  1994年   86篇
  1993年   111篇
  1992年   93篇
  1991年   89篇
  1990年   95篇
  1989年   89篇
  1988年   79篇
  1987年   99篇
  1986年   94篇
  1985年   109篇
  1984年   124篇
  1983年   123篇
  1982年   101篇
  1981年   107篇
  1980年   103篇
  1979年   100篇
  1978年   99篇
  1977年   96篇
  1976年   84篇
  1975年   90篇
  1974年   66篇
  1973年   63篇
  1972年   65篇
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
31.
32.
In this paper Aboriginal land rights are analysed from the perspective of a disadvantaged group seeking access to a scarce resource controlled by external agents. The Aboriginal participants in land rights politics are found to be actively seeking ways in which their interest in the land can most effectively be communicated to external groups which have constructed well-formed, but often distorted images of what constitutes a genuine Aboriginal interest in the land These externally constructed notions of Aboriginality and what constitutes a valid land claim are influencing the concepts used by Aboriginal groups in the public political arena to demonstrate their unique interest in the land In this paper three examples of this process are explored- the emphasis of a specific gender model, the emphasis on spatially discrete sacred sites and the emphasis on the bounded tribal territory.  相似文献   
33.
34.
Pompeiian-style (hourglass) grain mills are common at many Roman sites within the circum-Mediterranean countries. Three examples are known from Corfe Mullen, London and Hamworthy in southern Britain. Petrographic examination, chemical and microprobe analyses indicate that the Corfe Mullen millstone and the London donkey mill were imported from central France into southern Britain. The Hamworthy mill should be designated a ‘flat donkey mill’, and represents a recent (post-Roman) import from a volcanic source in Sardinia. There is no evidence of importation of Roman donkey mills from Germany or for transportation of such mills (or stylistic derivatives) north of London.  相似文献   
35.
36.
37.
ABSTRACT The origins and development of the network equilibrium problem are traced and interrelated. Two principal formulations are considered the network equilibrium problem with variable travel demand, and the combined model of trip distribution and traffic assignment. The relation of these models to subsequent developments concerning mode choice, residential location, estimation of origin-destination tables from link flows and stochastic route choice are then reviewed.  相似文献   
38.
39.
Discrete-choice theory and logit models are evaluated for their usefulness in analyzing migration patterns in a zonal system. The authors "argue that spatial effects and more specifically the relative location of zones are not taken into account in such analyses. We, therefore, introduce a measure of spatial structure and advocate its usage as a predictor of migration in such models. In an example of intrametropolitan migration in Toronto [Canada], we demonstrate that this variable is not only significant but also it improves the performance of all the other variables with the greatest impact on the distance between zones. In addition, inclusion of this variable improves the overall performance of the model in terms of residuals."  相似文献   
40.
"This paper presents a two-sector dynamic model of regional population change. The model contains a migration equation, an earnings equation, and an amenity equation for each region. In the context of this model, migration is seen as a disequilibrium process through which the regional populations move towards equilibrium positions. Migration occurs when one region is perceived to be superior to the other on the basis of its earnings and amenity levels. Equilibrium is achieved when population movements between the regions eliminate any differences in their relative attractiveness. A comparative-static analysis of the model is presented to analyze the effects of policy changes and exogenous shocks on the distribution of population among the regions." The geographical focus is on the United States.  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