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111.
Cycle mode share increase is widely desired, but highway design practitioners lack the numerical tools to deliver infrastructure, instead relying on design standards and intuition, with little literature basis. As a case in point, the US Highway Capacity Manual (which is well used internationally) has developed levels of service for cycle infrastructure that are, at their core, based on an assumption of noninteraction between multiple cyclists. This paper uses a modified implementation of the Social Force Model to test the validity of this assumption. Necessary changes such as the consideration of acceleration characteristics and minimum maintainable speed are included. The resulting model produces valid outcomes in keeping with established traffic flow properties, reflecting three-phase traffic flow theory and the ability for the stochastic elements in traffic flow to cause flow breakdown. The developed simulation indicates that there is a fundamental difference in outcome if cyclists are assumed to have a fixed speed versus one they can change given their surroundings. This difference in outcomes is found to exist within the range of literature design flow capacities for bicycle infrastructure and also yields emergent outcomes that align closely with those known behaviors of highway vehicles, which intuitively transfer to cyclists. These findings reinforce the standing need for large-scale empirical studies to determine the basic numerical and behavioral parameters for cyclists, upon which all design ultimately rests.  相似文献   
112.
The long-term sustainability of wildlife tourism depends on integrating visitor demands with resource management, requiring an understanding of tourist motivation. Managing the conflict between access to the animals and welfare, however, may diminish the experience for tourists. This paper identifies trade-offs tourists are willing to make between access and animal welfare, associated with feeding habituated bottlenose dolphins (Tursiops sp.) in Monkey Mia, Western Australia. Using a choice modelling technique, we were able to determine monetary values of visitor experiences. Compared to the current guaranteed interaction with dolphins (and a daily resort entrance fee), respondents were willing to pay significantly higher hypothetical entrance fees to avoid a decrease in proximity to, or probability of, the dolphin interaction. However, negative impacts on dolphin welfare had a negative impact on visitor utility. Over 80% of visitors (n = 244) accepted management regulations resulting in decreased time with and proximity to dolphins, if those addressed welfare concerns and were communicated clearly. Thus, while visitors placed the greatest value on the proximity and predictability, they were willing to trade off these aspects if they improved dolphin welfare. We provide management suggestions based on these results.  相似文献   
113.
An integrated methodological framework for ex-ante evaluation and planning of public policies for sustainable agriculture at agro-landscape level is proposed. The components of the framework are to: (1) determine the private, i.e. farmers’, and public benefits associated to agro-landscapes, consisting of an agricultural land-use system, according to its performance for several market and non-market functions. Market forces determine the market benefits and preferences of society the non-market benefits; (2) explore and select potential sustainable agro-landscapes based on the private and public benefits associated with possible land-use alternatives; (3) define efficient public policy mechanisms for improving social net benefit of agro-landscapes.The framework is illustrated with a case study in a small dairy farming dominated agro-landscape in The Netherlands, with gross margin, landscape quality, nature value and environmental health as the analysed ecosystem functions. Alternative landscapes consisting of hedgerow configurations and grassland management practices were explored, yielding a set of alternatives representing the solution space in terms of change in private and public benefits. Policy mechanisms were defined to move from the current to a desired landscape based on changes in social net benefits. Moreover, the necessity of a modification in the current agri-environmental support was analysed for each landscape. The analysis considered all farmers in the agro-landscape jointly. The results for the case study showed potential prototypes of landscapes and their performance compared to the current landscape. Extension was the most efficient policy mechanism to promote the change to the socially optimum landscape alternative.  相似文献   
114.
The valorisation of cross-cultural understanding and promotion of an ethic of global citizenship are at the forefront of the recent development and proliferation of international ‘gap year’ travel programs and policies. Governments and industry alike promote gap year travel uncritically as a guaranteed pathway to the development of inclusive ideologies associated with global citizenship. In this paper we examine how the neoliberalist context in which gap year travel programs have proliferated does little to promote tolerance. We then consider the recent growth of ‘volunteer tourism’ as an alternative gap year youth travel experience and explore how the implied resistance to self-serving neoliberalist values that it engenders can become coopted by neoliberalism.  相似文献   
115.
当前金融危机是经济周期的必然结果,其直接原因是以美元为核心的单体国际货币体系和保护主义日益严重导致的全球经济的长期失衡,要通过这场金融危机来平衡全球金融体系和经济的关系。因此,建立多元的国际货币体系,是这次金融危机之后最重大的金融制度的变革。目前金融还是现代经济的核心和心脏,不能因为金融危机而停止中国金融的市场化改革的步伐;同时,金融危机给中国带来了两个难得的机遇,即人民币的国际化和全球金融中心的构建。  相似文献   
116.
This paper assesses the impact of the ‘decoupling’ reform of the Common Agricultural Policy on the labour allocation decisions of Irish farmers. The agricultural household decision‐making model provides the conceptual and theoretical framework to examine the interaction between government subsidies and farmers’ time allocation decisions. The relationship postulated is that ‘decoupling’ of agricultural support from production would probably result in a decline in the return to farm labour but it would also lead to an increase in household wealth. The effect of these factors on how farmers allocate their time is tested empirically using labour participation and labour supply models. The models developed are sufficiently general for application elsewhere. The main findings for the Irish situation are that the decoupling of direct payments is likely to increase the probability of farmers participating in the off‐farm employment market and that the amount of time allocated to off‐farm work will increase.  相似文献   
117.
We review the basic principles for the evaluation of design efficiency in discrete choice modelling with a focus on efficiency of WTP estimates from the multinomial logit model. The discussion is developed under the realistic assumption that researchers can plausibly define a prior belief on the range of values for the utility coefficients. D‐, A‐, B‐, S‐ and C‐errors are compared as measures of design performance in applied studies and their rationale is discussed. An empirical example based on the generation and comparison of fifteen separate designs from a common set of assumptions illustrates the relevant considerations to the context of non‐market valuation, with particular emphasis placed on C‐efficiency. Conclusions are drawn for the practice of reporting in non‐market valuation and for future work on design research.  相似文献   
118.
研究目的:刻画、解构地方政府住宅用地出让价格跨区域联动系统。研究方法:全局向量自回归(GVAR)模型与网络分析工具。研究结果:(1)地方政府住宅用地出让价格跨区域联动系统呈现出高聚类、短路径的"小世界网络"特性。(2)地方政府住宅用地出让价格跨区域联动网络分为3个板块:板块1为"领导人"角色,板块2为"经纪人"角色,板块3为"谄媚人"角色。(3)地方政府住宅用地出让价格跨区域联动表现出明显的空间异质性。研究结论:应该从跨区域联动视角,深化对地方政府住宅用地出让价格形成机制的认识,有效管控地方政府住宅用地出让价格的跨区域影响。  相似文献   
119.
We analysed a county‐level data set of single‐season rice yield and daily weather outcomes in China to examine the effects of temperature on China's rice sector. We found that rice yield exhibited highly nonlinear responses to temperature changes: rice yield increased with temperature up to 28°C and decreased sharply with higher temperatures. Holding current growing seasons and regions constant, average rice yield in China is projected to decrease by 10–19 per cent by 2050 and 11–33 per cent by 2070 due to future warming under the global climate models HadGEM2‐ES and NorESM1‐M. These results imply that future warming poses a major challenge for Chinese rice farmers and that the effectiveness of adaptations will depend on how well they reduce the negative temperature impacts on rice yield because of very hot days.  相似文献   
120.
中国农业处于全球农业价值链的"微笑曲线"谷底,长期遭受不平等待遇。对农产品出口技术复杂度所作的测算显示,相对于G20国家而言,中国农业在全球农业价值链地位并不高,且与最高国家差距呈现逐渐扩大的趋势。对G20国家农业OFDI数据所作的面板回归表明,农业OFDI存在溢出效应,能够提升母国农业出口贸易品技术含量,且其提升需要"学习过程"。此外,农业FDI对出口贸易品技术含量的影响具有滞后性。据此,研究认为,中国为了实现全球农业价值链地位的攀升,应该进一步鼓励农业企业"走出去";改善农业投资环境,为外商直接投资创造条件;提高对外开放程度,为农业发展提供支持;推动金融体制改革,提高国内金融服务发展程度。  相似文献   
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