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   6802篇
  免费   337篇
  2020年   84篇
  2019年   119篇
  2018年   197篇
  2017年   198篇
  2016年   267篇
  2015年   175篇
  2014年   167篇
  2013年   1719篇
  2012年   180篇
  2011年   242篇
  2010年   195篇
  2009年   205篇
  2008年   164篇
  2007年   176篇
  2006年   170篇
  2005年   88篇
  2004年   94篇
  2003年   95篇
  2002年   82篇
  2001年   116篇
  2000年   108篇
  1999年   100篇
  1998年   86篇
  1997年   87篇
  1996年   66篇
  1995年   72篇
  1994年   52篇
  1993年   84篇
  1992年   62篇
  1991年   62篇
  1990年   63篇
  1989年   71篇
  1988年   50篇
  1987年   69篇
  1986年   57篇
  1985年   76篇
  1984年   71篇
  1983年   86篇
  1982年   71篇
  1981年   63篇
  1980年   73篇
  1979年   64篇
  1978年   71篇
  1977年   76篇
  1976年   77篇
  1975年   61篇
  1974年   56篇
  1973年   50篇
  1972年   48篇
  1971年   35篇
排序方式: 共有7139条查询结果,搜索用时 15 毫秒
41.
42.
43.
ABSTRACT. We determine the location equilibria in a duopoly model under a novel solution concept. Typically, spatial equilibrium is described as either a simultaneous price and location game, or else as a two-stage location-then-price game. We introduce a new alternative, a two-stage price-then-location game. It is well known that no (pure strategy) equilibrium usually exists under the two standard solution concepts when products are homogeneous. We show this is also true for the new concept. We then provide numerical results for a specific functional form (the logit model) which introduces product heterogeneity into the standard framework, restoring equilibrium when the degree of substitutability between products is not too small.  相似文献   
44.
45.
This paper is concerned with the products of a number of Neolithic quarries in highland Britain. It investigates the claim that the scale of axe distribution was partly the result of social factors which resulted in these artefacts gaining an added value in areas remote from their sources. One case study considers the sequence of production in Cumbria, in relation to the tensile strength of the rock quarried in different parts of the region. It shows that these considerations had only a limited influence over the choice of stone source and the scale on which it was worked. A second study compares the tensile strength of the main raw materials used for making non-flint axes with the extent to which these sources were actually exploited. Again there is only a limited relationship between the two, suggesting that social factors may indeed have been important.  相似文献   
46.
47.
48.
49.
Books reviewed in this article:
A. Comments
B. Book Notes
Abney, Glenn and Thomas P Lauth The Politics of State and City Administration
Adams, William J and Christran Stoffaes, (eds) French Industrial Policy
Binkin, Martin, Military Technology and Defense Manpower
Elazar, aniel J Cities of the Prairie Revisited The Closing of the Metropolitan Frontier
Ginsberg, Benjamin The Captive Public How Mass Opinion Promotes State Power
Heath, Robert L and Richard Alan Nelson Issues Management Corporate Public Policymaking in an Information Society
Hunt, Morton Profiles of Social Research The Scientific Study of Human Interactions
Kaplan, Marshall and Peggy Cuciti (eds) The Great Society and itsLegacy wenty Years of U S Social Policy
Katz, Michael B In the Shadow of the Poorhouse A Social History of Welfare in America
Katzmann, Robert A. Institutional Disability The Sage of Transporation Policy for the Disabled
Liroff, Richard A Reformaing Air Pollution Regulation The Toil Trouble of EPA's Bubble
Lowi, Theodore J The Personal President Power Invested Promise Unflfilled
Mead, Walter J, Asbjorn Moseidjord, Dennis D Muraoka, and Philip E Sorenson Offshore Lands. Oil and Gas Leasing and Conservation on th Outer Continental Shelf
Muskie, Edmund, Kenneth Rush, and Kenneth W Thompson The President, the Congress and Foreign Policy
Openshaw, Stan Nuclear Power. Siting and Safety
Peters, B Guy American Public Policy Promise and Performance
Rosentraub, Mark S, (ed) Urban Policy Problems Federal Policy and Institutional Change
Story, Dale Industry, the State, and Public Policy in Mexico
Taylor, Ralph B, (ed) Urban Neighborhoods Research and Policy
Wesson, Robert and Heraldo Munoz, (eds) Latin American Views of U S Policy
Winston, Brian isunderstanding Media
Zurcher, Louis A, Milton L Boykin, and Hardy L Merritt Citizen Sailors in a Changing Society Policy Issues for Manning the United StatesNaval Reserve  相似文献   
50.
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