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101.
We construct a model to illustrate that the current food stamp subsidy scheme fails to achieve its stated aim due to the crowding-out effect. More specifically, if the household income is sufficiently low, only a corner solution exists, and a full subsidy is needed. 相似文献
102.
Arnold Tukker R. Alexandra GoldbohmArjan de Koning Marieke VerheijdenRené Kleijn Oliver WolfIgnacio Pérez-Domínguez Jose M. Rueda-Cantuche 《Ecological Economics》2011,70(10):1776-1788
Food consumption causes, together with mobility, shelter and the use of electrical products, most life cycle impacts of consumption. Meat and dairy are among the highest contributors to environmental impacts from food consumption. A healthier diet might have less environmental impacts. Using the E3IOT environmentally extended input output database developed in an EU study on Environmental Impacts of Products (EIPRO), this paper estimates the difference in impacts between the European status quo and three simulated diet baskets, i.e. a pattern according to universal dietary recommendations, the same pattern with reduced meat consumption, and a ‘Mediterranean’ pattern with reduced meat consumption. Production technologies, protein and energy intake were kept constant. Though this implies just moderate dietary shifts, impact reductions of up to 8% were possible in reduced meat scenarios. The slightly changed food costs do not lead to significant first order rebound effects. Second order rebounds were estimated by applying the CAPRI partial equilibrium model. This analysis showed that European meat production sector will most likely respond by higher exports to compensate for losses on the domestic meat market. Higher impact reductions probably would need more drastic diet changes. 相似文献
103.
Luiz C.M. Miranda C.A.S. LimaAuthor vitae 《Technological Forecasting and Social Change》2011,78(8):1445-1470
Logistic and power law methodologies for both retrospective and prospective analyses of extended time series describing evolutionary growth processes, in environments with finite resources, are confronted. While power laws may eventually apply only to the early stages of said growth process, the Allee logistic model seems applicable over the entire span of a long range process. On applying the Allee logistic model to both the world population and the world gross domestic product time series, from 1 to 2008 AD, a projection was obtained that along the next few decades the world should experience a new economic boom phase with the world GDP peaking around the year 2020 and proceeding from then on towards a saturation value of about 142 trillion international dollars, while the world population should reach 8.9 billion people by 2050. These results were then used to forecast the behavior of the supply and consumption of energy and food, two of the main commodities that drive the world system. Our findings suggest that unless the currently prevailing focus on economic growth is changed into that of sustainable prosperity, human society may run into a period of serious economical and social struggles with unpredictable political consequences. 相似文献
104.
基于语言的人力资本性质,引入语言"Q值"量化其经济价值,并以此修正Grin模型分析小语种语言存在的必要性.分析结果表明:(1)语言的Q值越大时,也即这种语言的生命力越强时,人们投入这种语言的时间就会越多;(2)基于文化和政治上的原因,在小语种语言有必要保护的前提下,刻画出小语种语言存亡边界、改变小语种语言的语言态度以及小语种语言的使用人数,可以使小语种语言从死亡区进入生存区;(3)在对小语种语言保护的制度安排中,持久增加使用小语种语言的人数十分重要. 相似文献
105.
为了降低分集信号合成时输入信号的信噪比要求,提出了一种分集信号的中频合成方法
。该方法利用最大似然估计和迭代算法,通过计算输出合成信号和输入分集信号的相关值获
得合成权值,在中频实现信号合成。仿真和实验结果表明,该方法放宽了输入信号信噪比要
高于解调捕获门限这一要求,能自动实现最大合成增益。 相似文献
106.
107.
Stefano Mainardi 《Agricultural Economics》2011,42(1):17-33
For countries with recurrent droughts, the design of drought impact mitigation measures could benefit from analyses of determinants of yields and prices of local crops at regional and district level. This study applies dynamic spatial panel data regression models to yields and prices of four major food crops across regions of Burkina Faso and Niger, over sample periods between 1984 and 2006. Results lend support to mainly simultaneous spatial spillovers, particularly for millet and cowpea prices and sorghum yields in Niger, and maize yields in Burkina Faso. After accounting for these effects, most crop yields are found to be weakly price‐responsive, as envisaged by a supply‐side geographical diffusion hypothesis. Seasonal rainfall elasticity estimates suggest that dominant food crops have slight advantage margins in terms of relative resilience to rainfall shortages. However, this result is to be weighed against low millet yields in Niger, and marked drops in sorghum yields during officially declared droughts in Burkina Faso. 相似文献
108.
This study addresses the trade‐off between nutrition and taste in expenditure on breakfast cereal, milk, bread, and soft drinks. Within each category, products have similar cost and convenience, but have markedly different flavor and nutritional content. Using annual expenditure data for a large sample of households participating in the ACNielsen Homescan system, we regress a measure of “healthiness” on household demographics and market prices, and find that households with college‐educated heads and higher incomes made significantly healthier choices in all four categories. These effects are puzzling in that the nutritional differences between products were well known to consumers, and there are no cost or convenience differences between them. The presence of children was associated with less healthy choices, especially for cereal and bread, while older households made healthier choices in all categories except milk. 相似文献
109.
《Food Policy》2013
Demands for sixteen food products are investigated, using data from the Turkish Household Expenditure Survey. The linear approximate almost ideal demand system (LAIDS) is estimated with Shonkwiler and Yen’s two-step procedure. All own-price elasticities are negative and expenditure elasticities positive. Bread, other cereals, bovine, mutton, giblets, and cheese have high expenditure elasticities. Mutton, bovine, and several other protein-rich products are price elastic. Results suggest a mix of gross substitutes and complements, while net substitution is the dominant pattern. Demographic characteristics also play important roles in shaping food demand. The elasticity estimates can inform policy deliberations. 相似文献
110.
《Food Policy》2016
To meet the 2 °C climate target, deep cuts in greenhouse gas (GHG) emissions will be required for carbon dioxide from fossil fuels but, most likely, also for methane and nitrous oxide from agriculture and other sources. However, relatively little is known about the GHG mitigation potential in agriculture, in particular with respect to the combined effects of technological advancements and dietary changes. Here, we estimate the extent to which changes in technology and demand can reduce Swedish food-related GHG emissions necessary for meeting EU climate targets. This analysis is based on a detailed representation of the food and agriculture system, using 30 different food items.We find that food-related methane and nitrous oxide emissions can be reduced enough to meet the EU 2050 climate targets. Technologically, agriculture can improve in productivity and through implementation of specific mitigation measures. Under optimistic assumptions, these developments could cut current food-related methane and nitrous oxide emissions by nearly 50%. However, also dietary changes will almost certainly be necessary. Large reductions, by 50% or more, in ruminant meat (beef and mutton) consumption are, most likely, unavoidable if the EU targets are to be met. In contrast, continued high per-capita consumption of pork and poultry meat or dairy products might be accommodated within the climate targets. High dairy consumption, however, is only compatible with the targets if there are substantial advances in technology. Reducing food waste plays a minor role for meeting the climate targets, lowering emissions only by an additional 1–3%. 相似文献