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61.
Close relationships between and among supply chain members are becoming more prevalent. However, there is lack of agreement in the literature and in practice concerning the characteristics of different interorganizational relationships. The resultant confusion is an obstacle to the progression of research and could cause problems among firms in a supply chain. Based on previous research and an exploratory study conducted with company executives responsible for supply chain management activities, this article seeks to introduce the concept of relationship magnitude (i.e., the extent or degree of closeness or strength of the relationship) and differentiate it from relationship type (i.e., classes of relationships that share common traits). Implications for managers and opportunities for future research are provided.  相似文献   
62.
This work addresses the issue of climate change in the context of water resource planning on the time scale of a few years. Planning on this time scale generally ignores the role of climate change. However, where the climate of a region has already shifted, the use of historical data for planning purposes may be misleading. In order to test this, a case study is conducted for a region, the Australian Capital Territory, where long term drought is raising concerns of a possible climate shift. The issue is cast in terms of a particular planning decision; the option to augment water supply in the next few years to hedge against the drought persisting. A set of climate scenarios are constructed for the region corresponding to the historical climate regime and to regimes where progressively greater levels of change are assumed to have already taken place (5%, 10%, 20% reductions in mean rainfall). Probabilities of the drought persisting are calculated for each of the scenarios. The results show substantial increases in the probability of the drought persisting for even moderate reductions in mean rainfall. The sensitivity of the decision to augment supply to the scenario results depends ultimately on the planners tolerable thresholds for the probability of the drought persisting. The use of different scenarios enables planners to explore the sensitivity of the decision in terms of their risk tolerance to ongoing drought and to their degree of belief in each of the scenarios tested.  相似文献   
63.
64.
The status of invasive dreissenid mussels (Dreissena polymorpha and D. bugensis) and native amphipods (Diporeia spp.) in Lake Ontario was assessed in 2003 and compared with historical data. D. polymorpha (zebra mussels) were rarely observed in 2003, having been displaced by D. bugensis (quagga mussels). D. bugensis expanded its depth range from 38 m depth in 1995 to 174 m in 2003 and this dreissenid reached densities averaging 8,000/m2 at all sites < 90 m. During the same time period, Diporeia populations almost completely disappeared from 0–90 m depth, continuing a declining trend from 1994–1997 reported in previous studies. The average density of Diporeia in the 30–90 m depth interval decreased from 1,380/m2 to 63/m2 between 1997 and 2003. Prior to 2003, areas deeper than 90 m represented a refuge for Diporeia, but even these deep populations decreased, with densities declining from 2,181/m2 in 1999 to 545/m2 in 2003. Two common hypotheses for the decline of Diporeia in the Great Lakes are food limitation and a toxin/pathogen associated with dreissenid pseudofeces. The Diporeia decline in deep waters preceded the expansion of D. bugensis to these depths, and suggests that shallow dreissenid populations remotely influence profundal habitats. This pattern of decline is consistent with mechanisms that act from some distance including nearshore dreissenid grazing and downslope transport of pseudofeces.  相似文献   
65.
This paper formulates a new generation of Lowry-style models that combine a multizonal input-output model and an urban land use allocation model. Three different types of models are proposed: 1) an unconstrained model, 2) a primal of a linear programming approach that includes land supply constraints, and 3) a modified dual of the linear programming approach that allocates land based on additional conditions of economic efficiency. The modified dual formulation improves upon the limitations of Lowry models and their derivatives. First, the proposed model has sound theoretical underpinnings that incorporate the production theory of input-output models and the behavioral theory of optimization models. Second, the proposed model allocates land on the basis of economic efficiency by imposing a procedure that equalizes shadow prices. And third, the proposed model is an optimization model that fully accounts for the spatial and sectoral relationships of multiplier effects determining land use demand.  相似文献   
66.
A priority for the post‐apartheid government was the extension of basic infrastructure services to the vast majority of citizens that were not serviced under apartheid. The Reconstruction and Development Programme set objectives for each of these utilities that would be achieved in the first decade of democracy, while departmental policy aimed to find means of achieving these targets. The strategy of choice in most sectors was one of ambitious roll‐out targets being set for utility operators. Targets were set for individual residential service (‘universal service’) and for community service outside of individual homes (‘universal access’). While most utilities remained under public ownership, in telecommunications there was partial privatisation of the incumbent Telkom and the entry of privately owned mobile cellular operators. This article examines how roll‐out targets and licence conditions for universal service have performed in this sector where private operators exist. It examines the failure of the Telkom licence and draws out some lessons for policy.  相似文献   
67.
This article addresses the societal and cultural aspects of bioreserves and environmental restoration programmes. It begins with a discussion of bioreserves, then uses the example of a Man and Biosphere (MAB) inspired study of the US Everglades to illustrate how land has been shaped historically by culture and technology. It then demonstrates how current conflicts of values and culture, from both inside and outside the region, from interest groups with both pragmatic and emotional stances, are determining the future of an environment—the Everglades. The article thereby shows how human values and perceptions impact on the development of a sustainable Everglades, using the findings of surveys and public meetings to highlight the interests of the competing communities, ethnic and interest groups involved. If bioreserves are to survive they cannot become alienated from the people in the regions in which they are located.  相似文献   
68.
The importance of evaluating a discipline system from an ethical perspective is considered. Disciplinary practices in contemporary organizations are frequently characterized by managers having to choose from among alternative courses of corrective action. Since the selected alternative may have serious consequences for the individuals involved, its rightness or wrongness is of concern. The pattern of these choices reflects the overall disciplinary practice of the organization, and is an issue that warrants attention from an ethical perspective. Basic schools of thought that influence contemporary discipline practices are discussed and suggestions are made for conducting an evaluation of the ethical nature of a discipline system.  相似文献   
69.
Optimal new-product pricing in regulated industries   总被引:1,自引:0,他引:1  
Intertemporal pricing issues faced by regulated monopolists in market settings characterized by high rates of innovation have received little attention in the regulatory economics literature. Most analyses of regulatory pricing have focused on monopolies characterized by a stable multiple-good product set. In a regulated industry characterized by technological change in the form of new products and services (such as telecommunications), optimal pricing decisions may also reflect intertemporal market and production factors. In this paper, two such intertemporal factors are modeled: learning curve effects on the firm's cost function, and customer demonstration effects on the demand side of the market. Inclusion of these factors leads to an intertemporal pricing rule that may conflict with the standard regulatory practice whereby each product or service must recoup its own resource costs period by period. Our results suggest that this regulatory practice can result in efficiency losses, since it results in a rate of technological diffusion that is too low.  相似文献   
70.
We are grateful to a perceptive referee for many constructive comments on an earlier version of this paper entitled The Economics of Content Protection: A Dual Approach. The usual disclaimer applies.  相似文献   
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