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11.
City and Village in Iran: Settlement and Economy in the Kirman Basin. By Paul W. English. Madison, Wisc.: The University of Wisconsin Press, 1966. 204 pp. $6.75.
The Conflict of Traditionalism and Modernism in the Muslim Middle East. Edited with an Introduction by Carl Leiden. Austin: The University of Texas, 1966. 160 pp. $4.95. 相似文献
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Kim Richard Nossal 《Australian journal of political science》1991,26(1):29-50
Academic and political debates about international sanctions tend to focus on the instrumental purposes of these measures—their ability to hurt a target state sufficiently to cause it to change its behaviour. By contrast, the symbolic purposes of sanctions are commonly assumed not to be as important. Such assumptions are appropriate for states which have the capabilities necessary to achieve these ends—great powers or regional powers targetting very weak neighbours, for example. But are these assumptions useful in explaining the sanctions policies of non‐great powers, particularly those which impose sanctions against great powers? This paper explores the case of Australian and Canadian sanctions against the USSR after the invasion of Afghanistan and demonstrates the fallacy of such assumptions, and argues that symbolic purposes were much more important than the instrumental utilities normally associated with sanctions theory. 相似文献
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Daganzo (1977, 1979), Daganzo and Sheffi (1977), Sheffi (1985), and Sheffi and Daganzo (1980) have used one assumption about traveler behavior in developing estimation techniques for the stochastic route-choice problem and another assumption in predicting flows on networks by using the same model. In estimation, they calculate the congested travel costs of the network links from observed flows on the network, and the network is loaded based on these costs. In prediction, they follow their stochastic user-equilibrium assumption by which travelers evaluate costs using the mean of the observed flows (or equilibrium flows). The travel-cost coefficient obtained from the loading method systematically overestimates the true travel-cost coefficient from which the observed flow data (which must be used in loading) is generated. The estimates of the same coefficient, obtained in this paper, by constraining the estimation results to conform to the equilibrium conditions are unbiased, and only marginally less efficient (have larger standard deviations). The average percentage error and inefficiency of the link flow predictions based on the loading method increases as the level of congestion on the network rises. In contrast, the average percentage error of link flow predictions based on the equilibrium estimation method declines and their efficiency remains very high as the level of congestion on the network rises. 相似文献
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Farmer adaptation to climatic variability is explored via an analysis of corn hybrid selection in southern Ontario. Corn hybrid varieties are available for a wide range of conditions, including accumulated heat, measured as Corn Heat Units (chus). Hybrids with higher chu ratings generally have higher yields, so long as there is sufficient heat for them to mature. Farmers choose their hybrid varieties prior to the growing season, in the face of uncertainty about the chus that will accumulate at their location. Farmers in the sample counties showed a consistent tendency to adjust their hybrid selection on the basis of the previous year's growing conditions. After the high chu year of 1991, farmers chose significantly more longer-maturing and potentially higher-yielding, but riskier varieties. After the lower chu years of 1992 and 1993, farmers' hybrid selections became markedly more conservative. L'étude de I'adaptation des fermiers aux changements climatiques se fait par une analyse de /'hybridation du maïs au sud de l'Ontario. Les variétés de maïs hybrides conviennent à différentes conditions climatiques in-cluant la chaleur accumulée, mesurée en Unitées de Chaleur de Maïs (ucms). Les hybrides ayant une valeur ucm plus élevée donnent généralement un rendement plus élevéà condition qu'ils bénéficient d'assez de chaleur pour mûrir. Les fermiers des comtés sélectionnés ont démontré une tendance persistante à baser leurs sélections d'hybrides en fonction des conditions de crois-sance de I'année précédente. Depuis 1991, année ayant connu un taux élevé d'UCM, les fermiers ont opté pour un type d'hybride à croissance prolongée, au potentiel de rendement plus élevé mats également plus risqué. Les années 1992 et 1993 ayant connu un niveau ucm moins élevé, les fermiers ont alors sélectionné des hybrides plus traditionnels. 相似文献
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Effect(s) of the “No-Same-Color-Touching” Constraint on the Join-Count Statistic: A Simulation Study
Kim Lowell 《Geographical analysis》1997,29(4):339-353
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
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Philip R. Israilevich Geoffrey J. D. Hewings Michael Sonis & Graham R. Schindler 《Journal of regional science》1997,37(4):565-590
The sophistication of regional economic models has been demonstrated in numerous ways, most recently in the form of linking several modeling systems or in the expansion in the number of equations that can be manipulated successfully to produce impact analyses or forecasts. In this paper, an alternative perspective is employed. What do regional macro-level forecasts indicate about the process of structural change? A new methodology is illustrated that enables analysts to make forecasts of detailed structural change in the interindustry relations in an economy. Using a regional econometric input-output model developed for the Chicago metropolitan region, derived input-output tables are extracted for the period 1975–2016. These tables are then analyzed to determine the forecasted direction of structural changes for the region. The innovation illustrated here is based on a model that exploits the general equilibrium spirit of computable general equilibrium models through the adjustment of input coefficients to clear markets. 相似文献