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81.
We develop a new conceptual approach to locating inspection stations for hazardous vehicles, prevention, and compare it to the previous, punitive, philosophy of the flow-capturing location model. We implement this preventive protection philosophy with a new mixed integer program that maximizes hazard avoidance by locating a number of inspection stations to detect and remove hazardous vehicles as early in their trips as possible. We test the model's performance and analyze the spatial characteristics of solutions simulating several potential applications. Our computations demonstrate that a relaxed integer-linear program is overly demanding computationally and that a simple greedy heuristic lacks robustness. We suggest further approaches to developing more powerful and efficient solution methods.  相似文献   
82.
ABSTRACT. This paper uses new estimates of metropolitan factor demand and output supply functions to study how federal, state, and local fiscal policies affect metropolitan economies. We illustrate our work with findings for ten metropolitan areas in five states for changes in state corporate income taxes, local property taxes, the federal corporate income tax, an investment tax credit, interest rates, public capital stocks, output prices, and tax and regulatory policies affecting gross wages. It is clear from these simulations that a policy that is nominally the same everywhere will have repercussions that vary widely across regions and cities.  相似文献   
83.
This study examined landcover change during 1940–1988 in two contiguous landscapes of approximately 12,400 hectares in central Ohio, USA: an inertial till plain area and a more dynamic moraine area. Agriculture dominated both landscapes throughout, however, the cover of natural vegetation and urban-suburban development increased over time on the moraine while natural vegetation decreased and agriculture increased on the till plain. Markov process models for landcover change were constructed for three 14–17-year time intervals and for the entire forty-eight-year study period. Probabilities of self-replacement for agricultural lands (0.91–0.97) were higher and those for forests (0.54–0.65) lower than those reported for other landscapes. Predictions of landcover percentages for fifty years in the future were made using Markov process models derived from actual cover changes in 1940–1957, 1971–1988, and 1940–1988. All three models produced similar predictions for the inertial till plain area. In contrast, the three models' predictions differed considerably for the moraine area. Only the 1971–1988 transition matrix was sensitive to increases in urbanization and reforestation which began on the moraine in the 1970s. These results indicate that reliance on lengthy study intervals and net rates of change can obscure spatial and temporal patterns of landcover change that are caused by natural and socioeconomic factors operating on shorter time scales.  相似文献   
84.
ABSTRACT. In this paper a gravity model is formulated to model a hospital patient flow system. Both spatial and nonspatial measures of separation are used to estimate the model. Travel time was found to provide improved fits over linear distance in modeling patient flow behavior. Transformations of travel time (square root and log) were found to improve model performance further. Model diagnostics suggested additional spatial separation measurw, separation measure parameters demonstrated stability over time. The model is used to forecast the effects of health care financing reform and hospital closure on patient flows in an urban hospital market. Universal health coverage was found to dramatically improve access to hospital services for lower income patient populations. Hospitals at risk for closure were forecast to receive increased patient flows. Medical school hospitals are expected to lose patients after implementation of health reform, with important implications for graduate medical education. Hospital closures were shown to have negative effects on access to services in poor neighborhoods, but relatively little effect on access in the system as a whole.  相似文献   
85.
Book Reviews     
Ken Booth and Steve Smith (eds), International Relations Theory Today, Cambridge: Polity Press, 1995. xii + 367pp. $39.95 (paper).

Christine Sylvester, Feminist Theory and International Relations in a Postmodern Era. Cambridge: Cambridge University Press, 1994. xi + 265pp. $47.50 (paper).

Stephanie Lawson (ed.), The New Agenda for Global Security: Cooperating for Peace and Beyond. St. Leonards: Allen & Unwin/Department of International Relations, RSPAS, Australian National University, 1995. xi + 217pp. $24.95.

Anne O. Krueger, Economic Policies at Cross‐Purposes: The United States and Developing Countries. Washington, DC: Brookings Institution, 1993. xii + 253pp. $US36.95 (cloth).

Robert L. Paarlberg, Leadership Abroad Begins at Home: U.S. Foreign Economic Policy After the Cold War. Washington, DC: Brookings Institution, 1995. xxv + 115pp. $US28.95 (cloth); $US10.95 (paper).

Tony Brenton, The Greening of Machiavelli: The Evolution of International Environmental Politics. London: Royal Institute of International Affairs/Earthscan, 1994. xvii + 282pp. $UK14.95 (paper).

John Charmley, Churchill's Grand Alliance: The Anglo‐American Special Relationship, 1940–1957. London: Hodder & Stoughton, 1995. xv + 427pp. $55.00 (cloth).

Victor A. Kremenyuk, Conflicts In and Around Russia. Nation‐Building in Difficult Times. Westport: Greenwood Press, 1994. xiv + 159pp. $US49.95 (cloth).

Alexander Johnston, Sipho Shezi and Gavin Bradshaw (eds), Constitution‐making in the New South Africa. London and New York: Leicester University Press, 1993. viii + 272pp. $UK 39.50.

Ramesh Thakur, The Politics and Economics of India's Foreign Policy. London: Hurst and Company; New York: St. Martin's Press, 1994. xi + 306pp. No price given.

Francis Seow, To Catch a Tartar: A Dissident in Lee Kuan Yew's Prison (with a foreword by C.V. Devan Nair). Yale Southeast Asia Studies Monograph 42, New Haven: Yale Centre for International and Area Studies, 1994. xxxiii + 293pp. $50.00 (paper).

Brij Lal, Robert Kiste and Kerry Howe (eds), The Tides of History: The Pacific Islands in the 20th Century. St Leonards: Allen & Unwin, 1994. xviii + 475pp. $34.95 (paper).

LaMond Tullis, Unintended Consequences—Illegal Drugs and Drug Policies in Nine Countries. Boulder, CO: Lynne Rienner, 1995. ix + 229pp. $US42.00 (cloth).

The United Nations and Cambodia 1991–1995, The United Nations Blue Books Series, Vol. II. New York: Department of Public Information, United Nations, 1995. 352pp. $US29.95 (paper).

‘Atu Emberson‐Bain (ed.), Sustainable Development or Malignant Growth? Perspectives of Pacific Island Women. Suva, Fiji: Marama Publications, 1994. 290pp. No price given.

Payam Akhavan and Robert Howse (eds), Yugoslavia, the Former and Future: Reflections by Scholars front the Region. Washington, DC and Geneva: The Brookings Institution and The United Nations Research Institute for Social Development, 1995. xxviii + 188pp. $US32.95 (cloth) $US 12.95 (paper).

David Camroux, ‘Looking East’ . . . and Inwards: Internal Factors in Malaysian Foreign Relations during the Mahathir Era 1981–1994. Australia‐Asia Papers No. 72. Griffith University: Centre for the Study of Australia‐Asia Relations, 1994. iii + 62pp. $10.00.  相似文献   

86.
This article is a contribution to the debate on the nature of the modern Labor Party and a commentary on the extensive literature which the debate has produced (see Warhurst 1994). An important element in this literature is the argument that the modern Labor Party, led by Bob Hawke and Paul Keating, is no longer the party it once was, but is fundamentally different in its policies, and that indeed in its very nature it is alien to Labor traditions (Maddox 1989; Jaensch 1989; Beilharz 1994). This line of argument has been called, by Rick Kuhn, the discontinuity thesis, and is now known as such (Kuhn 1992). Along with others, I am not convinced by this thesis but would rather emphasise the continuities in Labor experience. Like Hugh Emy I believe that 'The contrast between the two [Whitlam and Hawke] has been overdrawn'. (Emy 1993, p. 20)  相似文献   
87.
The spatial analysis literature recognizes three sources of aggregation error, termed Source A, Source B, and Source C, which affect models relying on distance measurements between populations and facilities. We consider these effects with respect to aggregating from census enumeration areas to census tracts, on a popular location model. We identify a further source of aggregation error, which we dub Source D error, arising from the representation of facility sites by discrete points. Source D effects are of the same magnitude as Source A and B combined, much greater than Source C effects. Source D error is further significant, because, unlike Source A and B error, it can be eliminated only by disaggregating .
La littérature sur Vanalyse spatiale reconnaît trois sources d'erreur d'agrégation appelées erreurs de source A, B, et C. Ces erreurs influencent les modèles qui reposent sur des mesures de distance entre des populations et des installations. On considère les effets d'agrégation des secteurs de dénombrement en secteurs de recensement sur un modèle de localisation courant. On identifie une quatrième source d'erreur d'agrégation appelée erreur de source D. Cette erreur découle de la représentation des sites des installations par des points discrets. Ses effets sont du même ordre de grandeur que ceux des sources A et B combinées et beaucoup plus grands que les effets de source G. L'erreur de source D est d'autant plus significative à cause du fait que, contrairement aux erreurs de source A et B, elle ne peut être éliminée que par la désagrégation .  相似文献   
88.
This paper focuses on the strategies for production and work reorganization pursued in the Canadian newsprint industry during the 1990s. Many newsprint mill managers view new pulping technologies and increased labour process flexibility as the important keys to success in their never-ending quest to remain competitive in the U.S. market. These strategies are discussed in the context of two underlying themes: the nature of the particular competitive pressures faced by Canadian newsprint producers in the early 1990s and the specific nature of the labour process in newsprint mills. Evidence points to the central importance of achieving functional labour flexibility in newsprint mills and to the fact that numerical labour flexibility is not a viable strategy, given the continuous-process nature of the industry.
The Economics of Production, Technological Change, and Cost Competitiveness in the Newsprint Industry
Work Practices and Labour Conventions in the Newsprint Industry
Flexibility and the Quest for Competitive Efficiency in Canadian Newsprint Mills  相似文献   
89.
The join-count statistic is used to measure the tendency of polygons of a given map type to attract or repel polygons of the same or different map types. Yet in certain maps—for example, natural resources maps—it is often impossible for a polygon of a given type to touch another polygon of the same type. (This is the no-same-color or “No-Same-Type-Touching” (NSTT) constraint referred to in the title.) This violates an underlying assumption of the join-count statistic and may render its use to study certain spatial phenomena inappropriate—even for measuring spatial autocorrelation among polygons that are not the same type. This was explored using Monte Carlo simulation. For polygons of different types, it appears that results of the join-count statistic can be interpreted without any special consideration for the NSTT constraint provided there are a minimum of five to eight colors in the spatial system. For polygons of the same type, results can simply be ignored since it is known that no two polygons of the same type will touch.  相似文献   
90.
The resemblances between Melanesian Big Men and capitalist entrepreneurs have long fascinated anthropologists. However, even though traditional leaders in Melanesian societies resemble entrepreneurs in certain respects they are motivated by different concerns. In this paper, I consider the career of Noya of the Eastern Highlands of Papua New Guinea to demonstrate the contrasts and confluences between the roles of big man and that of entrepreneur. Noya is neither a traditional big-man nor a pure capitalist, but has drawn selectively upon the logic of each in his drive to achieve promience. His life story provides insights into how big-men articulate with the capitalist world system.  相似文献   
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