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11.
Deep geopolitical changes in the South Caucasus have considerably influenced the relationships of Iran and the three republics of Armenia, Azerbaijan and Georgia. Geographical location and strategic significance have made this region one of the most important in the world. Because of its historical affinities and socio-cultural links with the region's peoples, the Islamic Republic of Iran has expanded political-economic cooperation with them. The active presence of regional and trans-regional actors has directly affected this relation. This article mainly seeks to examine Iran's relations with the South Caucasus republics, considering the opportunities created since their independence following the collapse of the Soviet Union.  相似文献   
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There are many reinforced concrete structures throughout the world that have been built in the past decades that lack appropriate seismic details and reinforced by plain bars. To study the behavior of such buildings, seven beams have been tested under cyclic and monotonic load. The specimens include substandard specimens, with deficient seismic details and reinforced by plain bars, specimens designed in accordance with ACI-318-99 but reinforced by plain bars, and standard specimens reinforced by deformed bars. The tests indicate that the substandard specimens sustain relatively large slip of longitudinal bars, separation of specimen relative to foundation and sliding at large deformation phase, low initial stiffness ratio, limited lateral displacement capacity, and loss of nominal yield strength. The specimens reinforced by plain bars in accordance with ACI-318-99 perform almost similar to standard specimens with deformed bars, in terms of elastic stiffness and lateral displacement ductility; but, they sustain larger slip, and smaller yield strength. Failure of all specimens reinforced by plain bars is characterized by flexural cracks without visible shear failure. Residual shear strength of substandard specimens is modeled by dowel action of longitudinal bars to predict a lower limit for lateral strength of the specimens.  相似文献   
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Usually, allocation of resources is an optimization problem which involves a variety of conflicting economic, social, and ecological objectives. In such a process, advanced geographic analyst tool for manipulation of spatial data and satisfaction of multiple objectives is essential to the success of decision‐making. The present research intends to demonstrate the application of a multiobjective optimization method based on NSGA‐II 1 (we call it HNSGA‐II), along with Geographical Information System (GIS) 2 to select suitable sites for the establishment of large industrial units. Having defined the elements of HNSGA‐II for the site selection of industrial units, the method is tested on the data of Zanjan province, Iran, as the case study. The results showed that the proposed approach can easily find a variety of optimized solutions, giving the decision‐makers the possibility to opt for the most propitious solution. Using this method, the achievement level regarding each objective function can be studied for any of the nondominated solutions.  相似文献   
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This paper formulates a multiple discrete‐continuous probit (MDCP) land use model within a spatially explicit economic structural framework for land use change decisions. The spatial MDCP model is capable of predicting both the type and intensity of urban development patterns over large geographic areas, while also explicitly acknowledging geographic proximity‐based spatial dependencies in these patterns. At a methodological level, the paper focuses on specifying and estimating a spatial MDCP model that allows the dependent variable to exist in multiple discrete states with an intensity associated with each discrete state. The formulation also accommodates spatial dependencies, as well as spatial heterogeneity and heteroskedasticity, in the dependent variable, and should be applicable in a wide variety of fields where social and spatial dependencies between decision agents (or observation units) lead to spillover effects in multiple discrete‐continuous choices (or states). A simulation exercise is undertaken to evaluate the ability of the proposed maximum approximate composite marginal likelihood (MACML) approach to recover parameters from a cross‐sectional spatial MDCP model. The results show that the MACML approach does well in recovering parameters. An empirical demonstration of the approach is undertaken using the city of Austin parcel level land use data.  相似文献   
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The Poirier kinked exponential method as used by Boyce (1986) is adopted to examine changes in the Bangladeshi crop sector in the 1947–84 period using aggregate time series data. This is claimed to be a superior approach to earlier ones and it is the first time that non-cereal food crops have been given extensive consideration. Growth rates in output of major crops as well as commodity groups are estimated for various sub-periods with special emphasis on the changes in the period following the Green Revolution. The paper identifies a comparative ‘crowding out’ of non-cereal crop production as well as other food sources, e.g. fisheries, following the Green Revolution. On the whole, increased cereal production has been absorbed by rising population with per capita availability remaining roughly constant. The availability per capita of pulses, fruits and spices has fallen markedly in the post-Green Revolution period and on average per capita availability of vegetables has fallen. Furthermore, per capita protein content (both vegetable and animal) of the Bangladeshi diet has declined. The average Bangladeshi diet now appears to be less varied and balanced and a priori less nutritious with adverse welfare implications. Expansion of rice and wheat production has been at the expense of other sources of food such as pulses, fruit, vegetables and fish.  相似文献   
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Iran's scientific impact has suffered hard from decades of imposed and self‐elected isolation from Western influences and international collaboration. Lately, however, the world has witnessed a remarkable increase in scientific publications from Iranian scientists in fields like nanotechnology; material science; and, perhaps most pronounced, chemistry. In this article, the factors behind this “publication boom” are discussed and examined together with an analysis of the coherence between the country's long‐term research strategies and short‐term needs in relation to present organic chemical research conducted at various Iranian universities and institutes. Organic chemistry is a keystone in important Iranian industrial sectors like the petroleum and agricultural industries, and also in the growing field of life science and pharmacology. The development of the petroleum industry and further refinement of raw oil into value‐added fine chemicals holds a key position in the reinforcement of the Iranian economy and labor market, thus motivating a governmental investment in chemical science and research. Taking an approach to find a reasonable balance with the impact from Western and Far Eastern scientific communities, Iran's own scientific roots and Islamic ideology could well be the success factor in becoming a worthy player on the international scientific arena.  相似文献   
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This paper extends the utility maximization model of migration by introducing income and unemployment‐related uncertainties as determinants of utility, and analyzes the effects of the informational advantages of migrants. The paper maintains that migration would expand an individual's economic choices and opportunities and allow diversification. Consequently, diversification advantages influence the location decisions of migrants, an effect captured by the correlation of incomes at the origin and potential destinations. We use the discrete choice model based on random utility maximization as the framework for our empirical investigation of migration from the United States rural to urban counties. This paper takes advantage of an equivalent relation between the conditional logit model and Poisson regression to study the migration decisions using aggregate data among a large set of spatial alternatives. The results show that the diversification concerns have significant effects on location decisions of the rural‐urban migrants in the United States.  相似文献   
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