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141.
Sustainable technology development implies large changes in technological systems. The illustrative process ‘hydrogen fuel cell in a boat’ is used here as an example of a learning process concerning a transition towards a hydrogen economy. Theoretically the concepts of constructive technology assessment, back-casting and social niche management are combined in this approach.  相似文献   
142.
This paper develops a new test for speculative bubbles, which is applied to data for the Japanese yen, the German mark and the Canadian dollar exchange rates from 1977 to 1991. The test assumes that bubbles display a particular kind of regime-switching behaviour, which is shown to imply coefficient restrictions on a simple switching-regression model of exchange rate innovations. Test results are sensitive to the specification of exchange rate fundamentals and other factors. Evidence most consistent with the bubble hypothesis is found using an overshooting model of the Canadian dollar and a PPP model of the Japanese yen.  相似文献   
143.
The international transmission of shocks in population growth and technology is examined in an interdependent two-country world economy; decisions concerning the intertemporal allocation are made by social planners with an infinite horizon and an endogenous rate of time preference. Steady state shocks in population growth are shown to be negatively transmitted to the rate of time preference. In the steady state, the optimal foreign debt is determinate and it brings about a convergence of time preference. The net creditor and debtor positions in the steady state depend on the discount rate functions, the states of technology and the rates of population growth.  相似文献   
144.
145.
Sustainable land use planning is crucial for realizing the aim of food security and for combating land degradation in the Sahel. A participatory land use planning workshop was organised in a village in the eastern region of Burkina Faso to investigate land use problems, their causes, effects and possible solutions. Participatory research tools and GIS were combined to get insight into possible conflicts or synergies between different land use options as mapped by different ethnic groups. Pictograms were used to locate alternative land use options on the map, after which they were digitised for analysis with GIS. The workshop confirms the importance of integrating scientific and local knowledge to develop concrete options for sustainable land use that fit to local realities and aspirations. Local people are knowledgeable about the driving forces behind land degradation, they take actions to combat the effects of degradation, and they have concrete ideas about alternative land use options. The use of GIS proved its added value in the participatory process of integrated land use planning. The maps that were produced also facilitate discussions between community members, researchers and government representatives at the regional level, both regarding current land use problems and regarding alternative options as perceived by the local population.  相似文献   
146.
Growth and liberalization of world trade have increased the risks of introduction of quarantine plant pests into importing countries. Import inspection of incoming commodities is a major tool for prevention of pest introductions related to world trade, but inspection capacities are limited. This article develops a theoretical and an empirical model for the optimal allocation of inspection effort for phytosanitary inspection of imported commodities when the inspecting agency has a limited capacity. It is shown that the optimal allocation of inspection effort equalizes marginal costs of pest introduction across risky commodity pathways. The numerical illustration finds the optimal allocation of inspection effort of chrysanthemum cuttings imported in the Netherlands. The numerical results suggest that ceteris paribus , greater inspection effort should be allocated to pathways whose inspection yields a greater reduction in the expected costs of pest introduction. The numerical results also suggest that import inspection has a high marginal benefit. In particular, we found that each additional euro of the inspection capacity decreases the expected costs of pest introduction from 18 to 49 euros, depending on the initial inspection capacity.  相似文献   
147.
Decentralization of land governance is expected to significantly improve land tenure security of small‐scale farmers in Africa, through ensuring better protection of their assets and reducing land‐related conflicts. This paper, however, cautions not to have too high expectations of transferring responsibilities for land administration and dispute resolution to local government bodies. Field research in Mbarara District in south‐western Uganda brings out how decentralization has limited impacts in terms of localizing land services provision. Nonetheless, local land governance has transformed in important ways, as decentralization adds to institutional multiplicity, and fuels competition among state and non‐state authorities, and about the rules they apply. Rather than strengthening local mechanisms for securing tenure, the reforms introduce new forms of tenure insecurity, fail to transform local conventions of dealing with land disputes and delegitimize local mechanisms for securing tenure. In practice, decentralization has had limited effects in securing tenure for the rural poor, yet reinforces the presence of the state at the local level in diverse ways.  相似文献   
148.
The article examines the effect of membership in farmer groups (MFG) on adoption lag of agricultural technologies and farm performance in Burundi, the Democratic Republic of Congo and Rwanda. We use duration and stochastic production frontier models on farm household data. We find that the longer the duration of MFG, the shorter the adoption lag and much more so if combined with extension service delivery. Farmer groups function as an important mechanism for improving farm productivity through reduced technical inefficiency in input use. We discuss policy implications under which farmer groups are a useful channel to reduce adoption lag, and the means through which improved farm performance can be achieved.  相似文献   
149.
Misconduct in global meat supply chains are omnipresent and even more so in differentiated chains where credence attributes such as origin and taste are used to differentiate the product. By definition, these attributes signal asymmetric information which implies that in the presence of bounded rational individuals with conflicting interests, misconduct in the form of opportunistic behavior is bound to prevail. Increased information exchange through farmer networks is, however, expected to reduce opportunistic behavior. In the case of a differentiated meat product, such as Karoo Lamb, the article studies the farmer‐abattoir transaction with the purpose of recommending strategies that can be implemented to reduce the farmer's tendency to behave opportunistically. The article employs the PLS approach to SEM and reveals a significant negative relationship between information shared and opportunistic behavior. The results indicate significant positive relationships between trust in the abattoir and information shared as well as between farmer networks and information shared. These results are indicative of the support provided to the information shared construct by higher levels of trust between farmers and abattoirs and established farmer networks. It is, therefore, recommended that differentiated meat supply chains, through their various associations, concentrate their efforts to promote information sharing by building stronger, trust centered relationships and by supporting farmer networks.  相似文献   
150.
Research on location-based advertising (LBA) suggests that the merits of LBA lie in the fact that consumers can be targeted with location-congruent ads on their personal mobile devices. However, LBA consists of two underlying constructs: a mobile (vs. point-of-sales) advertising medium and location congruency (vs. location incongruency). This study aims to disentangle these underlying constructs by showing that they differentially affect the efficacy of an ad. Using a virtual reality lab experiment, this study shows that location-congruent ads result in increased choice for the target brand as compared to location-incongruent ads, independent of medium type. However, in location-incongruent situations, mobile ads attracted more attention than point-of-sales display ads. The advantages of LBA thus do not seem to emanate from medium type, but rather from the congruency between the ad and product location. When the ad is received at a different location than the product, the mobile medium is able to enhance consumers' ad attention.  相似文献   
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