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71.
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Land-use change has a significant impact on the world’s ecosystems. Changes in the extent and composition of forests, grasslands, wetlands and other ecosystems have large impacts on the provision of ecosystem services, biodiversity conservation and returns to landowners. While the change in private returns to landowners due to land-use change can often be measured, changes in the supply and value of ecosystem services and the provision of biodiversity conservation have been harder to quantify. In this paper we use a spatially explicit integrated modeling tool (InVEST) to quantify the changes in ecosystem services, habitat for biodiversity, and returns to landowners from land-use change in Minnesota from 1992 to 2001. We evaluate the impact of actual land-use change and a suite of alternative land-use change scenarios. We find a lack of concordance in the ranking of baseline and alternative land-use scenarios in terms of generation of private returns to landowners and net social benefits (private returns plus ecosystem service value). Returns to landowners are highest in a scenario with large-scale agricultural expansion. This scenario, however, generated the lowest net social benefits across all scenarios considered because of large losses in stored carbon and negative impacts on water quality. Further, this scenario resulted in the largest decline in habitat quality for general terrestrial biodiversity and forest songbirds. Our results illustrate the importance of taking ecosystem services into account in land-use and land-management decision-making and linking such decisions to incentives that accurately reflect social returns.  相似文献   
73.
Due to land use effects, bioenergy use may cause adverse effects on biodiversity, soil and water and may even fail to guarantee a GHG emissions reduction compared to fossil fuel use. Accounting methodologies and policy instruments were elaborated to prevent these effects, but there is still no sound and consensual methodology to take into account indirect land use change that substantially contributes to GHG emissions as well as a loss of biodiversity. While the iLUC hypothesis, that is the potentiality of adverse effects arising from indirect land use change related to biomass cultivation, is hardly subject to dispute, the quantification of these effects and especially their policy implications are however contentious. Hence, bioenergy policies worldwide face a dilemma: Neglecting iLUC effects that do in fact exist or taking them into account although no sound methodology is available? The article covers the current state of the discussion and also analyses the approaches developed for taking indirect land use change into account. Assessment criteria for coping with the iLUC dilemma are developed and policy recommendations are derived from that.  相似文献   
74.
This article describes the context and methodology used in formulating and validating a senior-level human resource competency model for professional development. The development and implementation of the architecture for the model, including the provision of various developmental tools and experiences, was undertaken by the Society of Human Resource Management, a professional association dedicated to the advancement of the human resource profession. The purpose of this effort is to specify benchmarks for professional competence building and to reposition the emerging role and processes associated with the human resource function in responding to the changing organizational and competitive challenges facing United States-based, multinational organizations. © 1996 by John Wiley & Sons, Inc.  相似文献   
75.
Many wildlife tourist attractions (WTAs) have negative impacts on animal welfare and species conservation. In the absence of regulation, raising standards requires tourists to create market pressure by choosing to attend WTAs with benefits for wildlife. We surveyed respondents from five countries – China, Australia, Canada, UK, and USA – to quantify how attitudes to captive animals, and towards WTAs’ outputs and standards, may vary with nationality. Our aim was to provide a firm basis for behaviour change interventions to alter current patterns of tourist consumption of WTAs. All respondents agreed on the importance of conservation and animal welfare, but Chinese respondents were twice as likely to believe that WTAs would not be allowed to exist if they were bad for animals, and that WTAs’ promotional materials were reliable indicators of welfare and conservation standards. These findings indicate Chinese respondents had fundamentally similar attitudes to those from the other countries, but differed in how those attitudes were likely to be applied. Chinese tourists may experience more barriers to aligning their actions with their values with respect to WTAs. Removing these barriers may require information campaigns to highlight the lack of regulation, and the unreliability of some WTAs’ promotional materials and tourists’ reviews.  相似文献   
76.
We estimate how much United States farms changed enterprise diversification in response to a marked increase in crop insurance coverage brought about by the 1994 Federal Crop Insurance Reform Act, which substantially increased insurance subsidies. The analysis exploits farm‐level panel census data to compare farm‐specific changes in enterprise diversification over time. By examining diversification decisions of the same farms over time, we control for time‐invariant unobserved individual heterogeneity. We then use pooled cross‐sectional data from the United States Department of Agriculture (USDA) Agricultural Resource Management Survey to estimate the relationship between farm diversification and average returns. We find that the insurance subsidies caused a modest increase in enterprise specialisation and production efficiency. Estimated efficiency gains are far less than the subsidies.  相似文献   
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The literature on stochastic input–output (I–O) analysis has paid considerable attention to the bias in the Leontief inverse. This paper extends previous studies by assuming supply and use tables (SUTs rather than I–O tables or input coefficients matrices) to be stochastic. This is a natural starting point because SUTs have become the basic data sources for I–O applications. In a Monte Carlo simulation experiment, a given SUT is randomized in two different ways and the effects are determined for eight different multiplier matrices. The analysis is carried out for Spain, Italy, the Netherlands, Germany and Finland, using their SUTs for 2006. The findings indicate that, in general, biases are statistically significant but negligibly small. This corroborates earlier findings obtained for stochastic I–O tables.  相似文献   
79.
Previous foot‐and‐mouth disease (FMD) outbreaks and simulation‐based analyses suggest substantial payoffs from detecting an incursion early. However, no economic measures for early detection have been analysed in an optimising framework. We investigate the use of bulk milk testing (BMT) for active surveillance against an FMD incursion in Australia. We find that BMT can be justified, but only when the FMD entry probability is sufficiently high or the cost of BMT is low. However, BMT is well suited for post‐outbreak surveillance, to shorten the length of time and size of an epidemic and to facilitate an earlier return to market.  相似文献   
80.
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