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1.
A systems model was estimated to determine the effects of declining U.S. retail beef demand on farm-level beef prices and production. Retail beef demand declined by nearly 66% from 1976 to 1999. Results indicate autonomous shifts in retail demand significantly impacted farm-level demands and production. Based on equilibrium multipliers, the 1976–99 reduction in beef demand decreased real slaughter cattle prices and production by 32.1% and 11.2%, respectively. Real feeder cattle prices and production decreased by 8.0% and 22.6%, respectively. Combining the decreases in farm prices and production, slaughter and feeder cattle producers experienced a real revenue reduction of $13.3 billion (61%) due to the long-term decline in demand.  相似文献   
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The Productivity of US States since 1880   总被引:1,自引:0,他引:1  
This study uses state-level variation in labor productivity levels at twenty-year intervals between 1880 and 1980 to examine the relative importance of institutional and geographical influences in explaining observed and persistent differences in standards of living over time and across regions. Focusing on fundamental rather than proximate influences, we find that both institutional characteristics and some physical geography characteristics account for a high proportion of the differences in state productivity levels: states with navigable waterways, a large minerals endowment, and no slaves in 1860, on average, had higher labor productivity levels throughout the sample period. However, we find little support for two other influences that have previously received attention—climate and latitude.  相似文献   
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Abstracts     
Quality & Quantity -  相似文献   
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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   
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The objective of this article is to analyze the domestic and international effects of a hypothetical foot‐and‐mouth disease (FMD) outbreak in the Mexican cattle industry. A discrete time dynamic optimization model of the Mexican cattle sector is specified, and linked to domestic and international markets. Economic consequences of FMD outbreaks are simulated over time and under different scenarios. Specific findings and general policy recommendations are provided. The study reports a range of outbreaks from localized to large scale and suggests that changes in economic surplus due to FMD range from a positive net gain of $0.89 to $1.6 billion to a net loss of about $67 billion, depending on the specific mitigation strategy and outbreak scenario.  相似文献   
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This paper describes dust explosibility research in full-scale experimental mines and a 20-L laboratory chamber at the U.S. Bureau of Mines and in a 1-m3 laboratory chamber at Fike Corporation. The purpose of this research is to improve safety in mining and other industries that manufacture, process, or use combustible dusts. As part of this work, carbonaceous dusts with a wide range of volatilities and various particle size distributions were studied. Laboratory data on the minimum explosible concentrations of predispersed dusts were comparable to mine data for nominal dust loadings that were dispersed by the aerodynamic disturbance from a gas ignition zone. Recommendations are given on the limitations of small-scale testing such as “overdriving” by too strong of an ignitor. The effect of dust particle size on explosibility data is illustrated for coal and aluminum dusts. For both dusts, the finest sizes were the most hazardous. The inerting requirements for preventing explosions were also measured in both laboratory and large-scale systems. All the data show relatively good agreement between the laboratory and the large-scale tests.  相似文献   
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Australia is the sixth largest producer of beef and the second largest exporter of beef. Average beef exports from Australia are approximately 65 per cent of the total amount of beef produced, about 1.3 million tonnes. Australia is particularly vulnerable to diseases that are not endemic to the country and could close or disrupt its export markets for beef. In this study, we construct a bioeconomic optimisation model of the Australian beef industry that captures production and consumption decisions, domestically and internationally, and the impacts on the beef industry of a potentially catastrophic disease, foot‐and‐mouth disease (FMD). This study analyses localised to large‐scale outbreaks and suggests that changes in economic surplus because of FMD range from a positive net gain of $57 million to a net loss of $1.7 billion, with impacts on producers and consumers varying depending on the location of the outbreak, control levels and the nature of any trade ban.  相似文献   
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We use panel data to estimate nonlinear Euler equations for preferences that are nonseparable in consumption and leisure. This approach departs from existing panel data studies that investigate linearizations and/or separable preferences. Intuitively plausible estimates are obtained only when excluding nonassetholders from the sample, which indicates the importance of asset market participation. For market participants, estimated parameter values are intuitively appealing, but differ from existing estimates. They also differ from parameter values commonly used in computational experiments. These findings have implications for the extensive literature in macroeconomics and finance that studies models of intertemporal decision-making, and they confirm the importance of market incompleteness.  相似文献   
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