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81.
A three-generation planning model incorporating uncertain climate change is developed. Each generation features a production activity based on capital and an exhaustible resource. An irreversible climate change may occur in period two or three, reducing the productivity for this and the remaining generation. The model is solved by stochastic dynamic programming. If the climate impact and climate change probability is constant, the optimal period one (and two) resource extraction is larger than for the reference case of climate stability. If, however, climate impact and climate change probability increases with increased aggregate resource use, this result is reversed.  相似文献   
82.
This paper aims to enhance our understanding of the relationship between organizations' strategic orientation (i.e., instrumental, equidistant, and stewardship) and their innovational strategy (i.e., organizational ambidexterity and open innovation), and this relationship's influence on their sustainability performance. We expected organizations' strategic orientation to influence their innovational strategy and exhibit better corporate sustainability. We focused on 12 different multinational organizations in the Eurozone and found that inbound open innovation acts as a driver for corporate sustainability while simultaneously positively enabling organizations to pursue both financial and social initiatives. After suggesting open innovation as a new corporate sustainability antecedent, we only found empirical evidence of inbound open innovation. However, we would suggest that if organizations incorporated outbound open innovation in their strategy, they could likely improve their corporate sustainability. Also, we found that achieving an equidistant or stewardship orientation paves the way for sustainability to become an integral part of an organization's innovational culture and actualizes the organization's strategic behavior. Our findings further contribute to a deeper understanding of organizations' characteristics as their sustainability commitment grows and as they move from an instrumental to a stewardship orientation and implement an open innovational strategy.  相似文献   
83.
创业氛围是一个地区所有族群成员关于创业的心智能力、价值观念和习俗惯例的集体和外在的表现。创业氛围是内生的,它是由创业活动衍生的创业学习、心理体验和社会互动的结果。创业氛围通过提升创业平均收益率和改变族群成员创业风险偏好,来提高创业惯例复制频率,进而提高地区创业活动水平。创业氛围与创业活动之间存在一个以知识累积和报酬激励为动力的正反馈演化路径。中西部地区促进创业活动的关键是,着力培育创业氛围并实现其临界突破。  相似文献   
84.
随着我国经济的快速发展,国家越来越重视铁路敞车车门检修问题以及工艺改进。为了进一步革新铁路敞车车门检修工艺,应当根据实际情况了解铁路敞车的车体组成部分,充分利用耐腐蚀性、密封性以及安全性等特性,对铁路敞车门锁安全进行综合分析和考量。论文主要针对铁路敞车车门检修中存在的问题及检修工艺进行简要分析,并提出一些合理化建议。  相似文献   
85.
A significant decline has been experienced in the quality of life of people living in cities due to the deterioration of the ecological balance, decrease in biodiversity, together with air, noise and water pollution occurring as a result of population growth and urbanization. All of these factors have triggered global warming, which is one of the biggest problems in recent years. For this reason, the climate has become one of the most important factors in urban design works. The purpose of the present study is to determine the microclimatic contribution of urban open spaces to the city in the context of climate-balanced physical planning criteria, and to propose an analytical model, which may constitute a basis for planning and design works. Firstly, the climatic requirements of the city of Gaziantep were examined by creating bioclimatic comfort maps. In the following stage, monthly wind roses were created by determining the dominant wind directions for the summer and winter seasons. Optimum location and directions that were balanced with climate were determined and slope and aspect maps of the area, land use types and area selection criteria were also created. In light of these data, ecological compatibility and feasibility maps were prepared. In the feasibility map, the temperature and humidity maps were created with ENVI-met, which is a climatic simulation software, for the most extreme days in an area where there were residential areas and educational institutions, multi-storey residential areas, working areas, social and open green areas, and afforestation areas. The results that were obtained with the simulations were subjected to Regression Analysis to determine the relationship among the climate parameters and the design criteria. As a result, the increase in the quantity of urban green spaces and equality on the spatial distribution of these areas will improve bioclimatic comfort (the warmest hour of the hottest period regression analysis’ result is β= -0.384). It has been determined that planning high-density plantation in green spaces and selecting dense and broad-leaved plants will provide a cooling effect (on average 2−3 °C less). Furthermore, adding more green spaces in cities will increase the thermal comfort within city blocks, especially where high-rise buildings are common. It is confirmed that high-rise buildings cause thermal stress (the warmest hour of the hottest period regression analysis’ result is β = 0.472). Hardscapes have a negative effect on the temperature (the warmest hour of the hottest period regression analysis’ result is β = 0.425). In addition to these data, it was found that the mean radiant temperature values, instead of temperature values, would yield more accurate results in microclimate analyses and interpretations.  相似文献   
86.
We consider a climate coalition that seeks to reduce global emissions in the presence of carbon leakage and resource exhaustibility. We show that a credible announcement of future unilateral supply‐side policies delays foreign emissions, and we derive the optimal combination of consumer taxes and producer taxes when we consider leakages from free riders, both within periods and across periods. The tax shares generally differ over time. A decline in the present value of the social cost of carbon over time supports a time path where the consumers’ tax share of the total carbon tax also declines over time. We illustrate our findings with a numerical model.  相似文献   
87.
We study the welfare effects of international monetary policy spillovers at the zero lower bound, focusing on the effects of forward guidance in a large economy (“foreign”) on its smaller trading partner (“home”) in scenarios motivated by the global financial crisis. We find that foreign forward guidance has an overall prosper-thy-neighbor effect on the home economy as long as it increases foreign welfare. This finding holds under alternative assumptions about exchange rate pass-through or the degree of international financial integration. However, foreign forward guidance may worsen the trade-off between the stabilization objectives of home monetary policy.  相似文献   
88.
This paper focuses on organizations and their management of climate risks. Climate risks stem from continued changes in climate means and the increase in frequency and intensity of extreme weather events. We ask whether companies also apply the usual process of corporate risk management to climate risks. In seeking to answer this question, we review several literature streams in order to set out an initial theoretical reflection. Based on this we conducted an exploratory case study with 11 electric utilities. Our results illustrate that these companies perceive climatic changes as a material issue for their business. However, management has restricted knowledge about such climatic changes and thus cannot precisely determine the potential negative impacts on business activities. As a consequence, the companies have implemented a climate risk management that does not differ from the usual process of managing other business risks. Our results further illustrate that there is some variation in how individual firms manage climate risks: While risk identification and risk assessment are equally important for all electric utilities, there are differences in how management determines the direction of the individual response to climate risks. Copyright © 2012 John Wiley & Sons, Ltd and ERP Environment.  相似文献   
89.
The literature on territorial innovation modes has identified the development of a diverse set of innovation systems at multiple levels of analysis. However, there are certain gaps that do not allow their adaptation to the particularities of certain territories. Despite the multiple concepts related to innovation systems approach, the state of the art does not yet provide a useful analytical approach for a deep and comprehensive characterization of territories with a high sectoral and technological specialization. This paper introduces an analytical framework based on a regional open and sectoral innovation system, which is qualitatively tested in the Durango County (Spain). The aim of this paper is to introduce a subtype of innovation system that meets the requirements and needs of a located micro-territory with a high level of sectoral specialization.  相似文献   
90.
气候变化对欧洲农业的系统影响及对策   总被引:1,自引:0,他引:1  
本文基于欧洲气候变化的历史演进与未来情景,系统分析了气候变化对欧洲农业的历史和潜在影响,提供了欧洲农业应对气候变化的适应性措施,及其对中国未来农业发展的启示和建议。  相似文献   
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