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151.
Research summary> : W e take a microfoundational approach to understanding the origin of heterogeneity in firms' capacity to adapt to technological change. We develop a computational model of individual‐level learning in an organizational setting characterized by interdependence and ambiguity. The model leads to organizational outcomes with the canonical properties of routines: constancy, efficacy, and organizational memory. At the same time, the process generating these outcomes also produces heterogeneity in firms' adaptive capacity to different types of technological change. An implication is that exploration policy in the formative period of routine development can influence a firm's capacity to adapt to change in maturity. This points to a host of strategic trade‐offs, not only between performance and adaptive capacity, but also between adaptive capacities to different forms of change . Managerial summary : W hy are firms differentially effective at adapting to technological change? We argue that firms differ in the adaptive capacity of the routines that underlie their capabilities. These differences arise well before change occurs, and result because firms build routines that are differentially responsive to signals of performance decline associated with technological change. Thus, early managerial efforts to build superior productive efficiency must be complemented by efforts to build superior adaptive capacity. Our theory suggests that managers can prepare for technological change by implementing policies, in the formative period of organizational development, that promote individuals' exploration of novel actions. However, there are trade‐offs because preparation aimed at building adaptive capacity to one type of technological change may limit adaptive capacity to other types of change . Copyright © 2016 John Wiley & Sons, Ltd.  相似文献   
152.
为服务土地管理实践,从耕地人口承载力、建设用地人口承载力的角度研究了安徽省及各市县的土地承载力,还从生态环境承载量的角度研究了建设用地最大量。研究结果表明,安徽省建设用地还有很大挖潜空间。按人均100m2计算,安徽省及各市建设用地人口承载水平在20%~40%之间。多元回归结果表明,区域常住人口、土地总面积对建设用地人口承载水平的影响显著。但GDP、人均GDP和二三产业占比对建设用地人口承载力的影响不显著。利用GIS的研究表明,在扣除生态必需用地后,安徽省建设用地生态适宜量为36 847km2,超过目前的建设用地总面积。耕地人口承载力研究结果表明,安徽省目前的耕地面积能满足全省常住人口粮食需求,但各市县差别很大。若不提高单产,在耕地面积不断减少的情况下,安徽省到2020年可能会面临粮食缺口。  相似文献   
153.
乡村生态旅游是农业和旅游业发展相结合的产业,其作为农村经济发展的重要引擎,已然成为解决"三农"问题的重要渠道。重庆位于我国西南地区,农业历史悠久,旅游资源发达,乡村生态旅游发展已经初现规模。但由于重庆整体经济水平在全国处于中游,加上城市基础设施投入占去政府财政支出的大部分,因此发展乡村生态旅游项目面临资金短缺和管理不善的困境。BOT模式是私营企业参与基础设施建设,向社会提供公共服务的一种方式,在我国又被称为"特许经营权",是指政府将"特许经营权"下放给私营企业,允许其参与建设和运营公共设施项目,并通过经营和管理获得利润回报的一种营销运作模式。BOT形式适用于我国当前乡村生态旅游项目的开发和发展,对改善乡村旅游项目资金不足问题及提高项目管理水平具有明显的促进作用。但BOT模式也存在诸如规划风险、道德风险和圈地风险等现实问题,需要从政府和企业等2个角度分别采取有效措施,包括加强立法工作、加大政府监管力度和制定严格的BOT协议等。  相似文献   
154.
[目的]农业可持续发展的研究首先面临的一个问题是如何对其进行有效评价,农业可持续发展评价一般采用多指标评价法,然而过多的指标给实际操作带来很多困难。文章从可持续发展评价理论创新和方法创新的需求出发,寻求建立一个简便易行的综合性指标——农业可持续发展指数(ASDI),以提高农业可持续发展评价的有效应和准确性。[方法]该文基于能量投入产出方法,利用Logistic曲线构建了ASDI,并以贵州省印江县为实证研究案例,对其农业生态的可持续性行进行评价分析。[结果]通过研究发现印江县的ASDI具有很大波动性,由于2002~2007年农业投入增加,印江县的ASDI呈现下降趋势,其中2007年因为投入过多而出现了负效应指数。[结论](1)利用一个简单的综合指标来评价农业可持续发展在理论和实践上是可行的;(2)ASDI作为农业可持续发展的研究,或将为生态安全预警提供了一个可供参考的指标。  相似文献   
155.
Dolphin-watching tourism is growing globally. In developing countries, the typically low environmental awareness of operators and poorly enforced or non-existent regulations exacerbate risks to wildlife. Ecological indicators like behavioural responses are useful to assess wildlife tourism, but obtaining such data is slow and expensive. We modified the Driver–Pressure–State–Impact–Response (DPSIR) framework to rapidly assess the risk of dolphin-watching tourism harming, displacing or causing local extinction to dolphin populations, using human dimension data to complement limited ecological data. We assessed industries at seven dolphin-watching sites in six countries in Asia: Cambodia, India, Indonesia, Malaysia, Thailand, and the Philippines. All sites have reached or almost reached financial saturation except Cambodia and Malaysia. We find high risk to dolphins at the sites in India and Indonesia and intermediate risk at the site in Cambodia. Pending more ecological data, the risk at Thailand, the Philippines, and Malaysian sites might be low. Our analysis also indicates site-specific conservation recommendations for Driver, Pressure and Response. We suggest that the DPSIR framework is useful to assess the risk of a wildlife watching industry, even when the impact is uncertain due to insufficient ecological data.  相似文献   
156.
Recognizing the socio-economic and biophysical causes of land degradation at the national level is important for cause-targeted strategies when designing policies for combating land degradation. This study aims to identify the biophysical and socio-economic factors that significantly affect land degradation across Vietnam and to interpret the causalities underlying the effects. The dependent variables considered in the study are spatial, the extent and intensity of degradation in three land-use zones (agriculture, forest and severely degraded abandonment). The hypothesized explanatory variables are common economic and demographic drivers and bio-physical factors such as soil, terrain constraints, and neighborhood land-use structures that are often neglected in many large-scale land degradation assessments. Instead of using a single inferential statistic technique, we used multi-linear regression and binary logistic regression in a complementary manner to increase the detectability and credibility of the degradation cause analyses. The results showed agricultural production growth had strong and consistent effects on land degradation extent and intensity. Population growth, especially in rural areas, had a strong effect on the extent of overall land degradation. The importance of a neighboring forest was revealed for its ability to reduce land degradation intensity in abandoned, unproductive lands. The concrete faceting of the causal analysis for each land-use zone as social–ecological stratum allowed us to combine the defined social–ecological contexts, contemporary theories, and hypotheses in the field to clarify the causal factors of a complex phenomenon like land degradation. The study demonstrates these contemporary inferential statistics can be complementarily used to sufficiently detect and understand land degradation causes at the national level. The results suggest implications for national land management policy: internalizing land degradation costs in the farming system evaluation for payment for ecosystem services policy, restricting forest conversion, and improving extension services and education in agrarian communities.  相似文献   
157.
[目的]碳足迹及碳承载力的时空演变分析是当前分析温室气体排放量的热点问题。[方法]文章采用2004~2014年河北省化石能源消费数据、土地利用结构数据以及经济社会数据,通过构建碳足迹模型,基于Arc GIS平台对河北省11个地级市的碳足迹、碳承载力、净碳足迹进行时空演变分析。[结果](1)2004~2014年河北省碳足迹由2.224 5亿t增长至4.792 2亿t,其中煤炭能源消费量占90%左右,唐山、邯郸和石家庄碳足迹值较高,分别占河北省碳足迹的33%、18%和16%;(2)2004~2014年河北省碳承载力由9 043万t增长至1.050 6亿t,其中林地碳承载力占河北省碳承载力的97%左右,西南地区农、林业发达,碳承载力相对较高;(3)2004~2014年河北省净碳足迹呈逐年上升趋势,由1.536 7亿t增长至4.236 5亿t,唐山、邯郸及石家庄净碳足迹较大,分别占河北省净碳足迹的40%、22%和16%;(4)除保定外,其他10个地级市的碳足迹压力指数变化强度均呈现不同程度的增强趋势。此次研究成果将为河北省未来制定温室气体排放量等相关政策的建设提供参考。[结论]整体来看,河北省碳足迹及碳承载力呈逐年增长的变化趋势,应加强温室气体的管控力度,减小碳排放给河北省带来的负面影响。  相似文献   
158.
国土空间生态修复是推进生态文明建设的重大举措,构建基于底线预警的国土空间生态修复规划实施监督体系是完善国土空间规划“一张图”信息系统的重要组成部分和政策支撑。通过对生态修复规划实施监督体系建设的研究,把握底线控制与监测预警机制,对接国土空间生态修复业务管理各项需求,搭建“五梯度四体系”的生态修复规划动态监测实施监督信息系统,构建以“七个一”为主要内容的生态修复规划底线预警监测评估机制,并与各层级国土空间规划“一张图”实施监督信息系统进行衔接,实现对生态修复规划实施的动态监测和预警。  相似文献   
159.
[目的]通过探讨关中—天水经济区水资源状况,可为经济区水资源的合理配置与经济社会的协调、可持续发展提供决策参考。[方法]根据关中—天水经济区2007~2016年相关统计资料,采用主成分分析法和构建指标体系对经济区水资源承载力从时间和空间两个角度进行综合评价。[结果](1)经济区水资源承载力得分由2007年的-0.067增加至2016年的1.877,水资源承载力与开发利用潜力呈现由大到小的变化,而水资源开发利用强度则呈逐渐增大趋势。(2)经济区各地市间水资源承载力存在显著差异,西安、咸阳两地的水资源承载力得分最高,均超过1.300,但水资源承载力和开发利用潜力最小;而杨凌、铜川两地的水资源承载力得分最低,均小于-2.250,但水资源承载力和开发利用潜力则最大。(3)经济发展水平、人口数量、水资源供需量、工农业生产用水是影响经济区水资源承载力大小的主要因素;其中,经济发展水平的贡献最大。[结论]经济区水资源承载力与开发利用潜力变小,开发利用强度增大;各地市间水资源承载力差异显著,将在一定程度上对经济区人口、经济、环境可持续发展起着明显的制约作用。为了促进经济区经济社会的健康可持续发展,应加强对水资源的管理与废水处理,合理控制经济区人口容量,提高社会节水意识,转变经济发展模式,大力推行节水型与节约型经济发展道路。  相似文献   
160.
The choice between specialisation and diversification of income is driven by multiple, interacting factors, such as economies of scale and scope, risk considerations, context, and household characteristics. Using panel data from Ethiopia, we investigate the role of social capital and the covariate risk of climate change and their interaction. We find that households with greater social capital tend to be more specialised, implying that diversification and informal insurance are substitutes in the mitigation of risk. We also find that this effect is significantly weaker in regions more prone to climate change, which is consistent with the average farmer being aware that informal insurance is not an effective protection against risks that affect the entire social network. We use instrumental variable random effects estimation to account for the plausible endogeneity of social capital and we also establish that our results do not depend on the poorest and most constrained individuals in our sample.  相似文献   
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