首页 | 本学科首页   官方微博 | 高级检索  
文章检索
  按 检索   检索词:      
出版年份:   被引次数:   他引次数: 提示:输入*表示无穷大
  收费全文   22449篇
  免费   895篇
  国内免费   400篇
财政金融   2229篇
工业经济   1109篇
计划管理   5042篇
经济学   4451篇
综合类   2381篇
运输经济   332篇
旅游经济   505篇
贸易经济   2783篇
农业经济   2328篇
经济概况   2584篇
  2024年   93篇
  2023年   468篇
  2022年   487篇
  2021年   728篇
  2020年   929篇
  2019年   683篇
  2018年   603篇
  2017年   843篇
  2016年   788篇
  2015年   777篇
  2014年   1609篇
  2013年   2021篇
  2012年   1818篇
  2011年   2091篇
  2010年   1535篇
  2009年   1398篇
  2008年   1495篇
  2007年   1321篇
  2006年   1114篇
  2005年   868篇
  2004年   577篇
  2003年   378篇
  2002年   245篇
  2001年   196篇
  2000年   166篇
  1999年   101篇
  1998年   89篇
  1997年   58篇
  1996年   55篇
  1995年   37篇
  1994年   39篇
  1993年   23篇
  1992年   32篇
  1991年   15篇
  1990年   6篇
  1989年   6篇
  1988年   7篇
  1987年   3篇
  1986年   9篇
  1985年   15篇
  1984年   11篇
  1983年   3篇
  1982年   2篇
  1981年   2篇
排序方式: 共有10000条查询结果,搜索用时 734 毫秒
991.
We analyse the effects of interest rate variations on the rates of capacity utilisation, capital accumulation and profit in a simple post-Kaleckian distribution and growth model. This model gives rise to different potential accumulation regimes depending on the values of the parameters in the investment, saving and distribution function. Estimating these core behavioural equations for the US and Germany in the period 1960–2007, we find significant and robust effects of interest payments with the expected sign in each of the equations. Our estimation results imply, both for the US and for Germany, that the effects of changes in the real long-term rate of interest on the equilibrium rates of capacity utilisation, capital accumulation and profits, are characterised by the ‘normal regime’: rising long-term real rates of interest cause falling rates of capacity utilisation, capital accumulation and profits, as well as redistribution at the expense of labour income and hence an increasing profit share in both countries.  相似文献   
992.
This paper presents a simulation-based modelling approach for estimating total visitor numbers and amenity values for prospective non-priced open-access outdoor recreation sites. To begin, the geographic extent of the market for recreation at a policy site is estimated using data from a similar study site. The population residing within this geographic area is simulated using a spatial microsimulation model and GIS techniques and an individual-level ‘visitor arrival function’ is then transferred across this simulated population. This allows the latent demand for visits to the policy site by each simulated individual to be predicted and summed, providing an estimate of the total potential demand for recreation at the site. Combining this with an economic value measure of a visit provides an estimate of the potential amenity value of the policy site. The approach is applied to Moyode Wood, a small-scale forest in the West of Ireland, and estimates the potential total economic value of recreation at €0.4 million for the site. The research represents the first time that spatial microsimulation has been used in environmental benefit transfer and shows how it can be used to control for differences in demographic and spatial factors between study and policy sites. It also demonstrates how individual-level single-site travel cost models estimated using on-site survey data can be used to predict demand at alternative policy sites.  相似文献   
993.
The objective of this research was to determine whether willingness to bear the negative externality from water quality impairment differs between those who do and those who do not receive economic benefit from the impairment source. Differences were tested using a hedonic analysis of ambient water quality in two discrete housing markets in the Pigeon River Watershed, which have been polluted by the operation of a paper mill. The results suggest that North Carolina residents residing in subwatersheds with impaired portions of the Pigeon River, who experience economic benefit from the paper mill in addition to its harmful effects on water quality, do perceive the pollution as a negative externality. In contrast, the effects of both the degraded river and its contributing streams on property values are perceived as negative externalities by watershed residents in Tennessee who experience only harmful effects from the pollution. Differences in willingness to bear the water-impairment externality were not indicated by variables representing view of and proximity to impaired water bodies. The results suggest that the perception of water quality to which property owners implicitly apply value should be considered when establishing water-quality regulations.  相似文献   
994.
Managing the introduction of nonindigenous species is becoming a major goal of policy-makers at regional, national and international scales. Here we investigate, at the national level, the ideal design and expected net benefits of a risk assessment program for evaluating the desirability of nonindigenous species imports. We show how to enhance the statistical rigor of such a system by correcting a common non-random sampling problem encountered in the data. This correction enables model output to be interpreted in an economically relevant way and facilitates a theoretically rigorous characterization of the balance between trade and nonindigenous species establishment risk. Using reptiles and amphibians imported to the U.S. as a case study, we characterize economic outcomes over a range of cases and demonstrate substantial expected returns to such a screening program, relative to the current effectively open-door policy. Our results are informative for the current debate in the U.S. about whether to require federal agencies to apply risk assessment before allowing a species for import. The framework presented decomposes a complex argument about risk management into component economic and statistical parts, allowing for debate and improved understanding over each element to inform the overall program in a transparent fashion.  相似文献   
995.
Land use change and land management intensification are major drivers of biodiversity loss, especially in agricultural landscapes, that cover a large and increasing share of the world's surface. Incentive-based agri-environmental policies are designed to influence farmers' land-use decisions in order to mitigate environmental degradation. This paper evaluates the effectiveness of agri-environmental schemes for biological conservation in a dynamic agricultural landscape under economic uncertainty. We develop a dynamic ecological economic model of agricultural land-use and spatially explicit population dynamics. We then relate policies (subsidies to grassland, taxation of agricultural intensity) to the ecological outcome (probability of persistence of a species of interest). We also analyze the associated trade-offs between agricultural production (in value) and biological conservation (in probability of persistence) at the landscape scale.  相似文献   
996.
皖江城市带城市经济联系与中心城市辐射范围分析   总被引:7,自引:1,他引:6  
分析经济区内城市间经济联系不仅有利于引导城市的空间发展,而且有利于空间经济的合理组织。以皖江城市带为例,引入克鲁格曼指数、建成区面积、人口素质权重系数等指标修正了以往的引力模型,并利用城市间的日发车班次数据对修正模型进行了检验。在此基础上,利用修正模型确定了各城市的主要对外联系方向及联系强度,采用断裂点公式计算了中心城市的吸引范围。结果表明:①皖江城市带内各城市对外经济联系强度差异较大;②各城市的主要联系方向呈现中心城市指向性和地域相邻指向性特征;③合肥和芜湖为皖江城市带的两个经济中心城市,它们的对外吸引范围较为狭小。  相似文献   
997.
家庭直接能耗的碳排放影响因素研究进展   总被引:4,自引:2,他引:2  
张艳  秦耀辰 《经济地理》2011,31(2):284-288,293
家庭能源消费对环境的影响已经成为可持续发展领域热点研究课题之一。为了更好地开展家庭直接能耗的碳排放研究,对国际上近20年的研究进行总结分析,将国际上对家庭直接能耗碳排放影响因素的研究模型归纳为自上而下模型、自下而上模型及综合模型三大类,并对各种模型进行了评价;国际上对家庭直接能耗碳排放影响因素的研究集中于家庭外部环境、家庭特征及家庭成员3个方面。分析表明:家庭直接能耗碳排放影响因素的研究模型由简单走向综合;所用数据由历史统计数据到与微观住户调研数据相结合;研究的层面由国家(地区)、城市、社区向家庭内部全面展开;分析的视角由单一的宏观分析,到宏观与微观分析相结合。在基本反映家庭直接能耗碳排放影响因素研究的最新态势的同时,提出了我国家庭直接能耗碳排放影响因素研究中值得注意的几个问题。  相似文献   
998.
以1990—2007年江苏省县域人均GDP为研究指标,运用不平衡指数和空间统计模型对江苏省区域经济发展水平进行定量研究,并结合GIS的空间分析功能,系统分析了江苏省区域经济发展时空差异及空间格局演化。结果表明:江苏省区域经济发展在空间上具有较强的自相关性,在整体格局上呈现出一定的集聚态势,空间格局更多表现为苏南部分地区的高度集聚和苏北部分地区的集聚态势,成为江苏省区域经济发展的集聚核心区和低度集聚区,而苏中地区的集聚态势显得并不强烈。同时,针对区域经济自相关性发展趋势进行解释并指出以县域经济为单元的区域经济发展空间差异将长期存在。最后,构建空间数据模型对此种格局形成的原因进行空间统计学上的探讨,指出规模企业空间分布差异及人才空间分布差异是导致县域经济发展差异的主要因素,为区域经济差异分析提供了一种交互式的、可视化的新手段,进而为政府部门制定区域经济协调发展政策提供决策依据。  相似文献   
999.
基于PSR模型的广东省城市土地集约利用空间差异分析   总被引:6,自引:0,他引:6  
朱一中  曹裕 《经济地理》2011,31(8):1375-1380
将"压力—状态—响应"框架引入到城市土地集约利用评价指标体系中,采用主成分分析方法对评价指标进行赋权,对广东省21个地级市的城市土地集约利用水平进行了评价。结果表明,广东省城市土地利用集约度差异形成的主要影响因素是地理区位条件和经济发展水平,资源赋存状况也是重要的制约条件。城市土地集约利用是一个复杂的系统工程,不仅要注重提高土地利用的产出效益,还要重视系统压力状态的调节和系统反馈能力建设。研究也表明,PSR评价指标体系及主成分分析方法能较好地适应城市土地集约利用评价的需要。  相似文献   
1000.
"双核"结构是区域经济发展中出现的一种空间结构形态。文章在分析潮汕地区潮州—汕头"双核"空间结构现状的基础上,提出了构建潮州—汕头"双核"结构区的旅游空间发展模式和具体旅游开发模式。认为在海西经济区旅游大发展的背景下,潮汕地区必须构建合理的发展模式,即:以汕头为区域旅游发展的主核心点,以潮州为次核心点,双核形成旅游发展核心区;以揭阳、汕尾为连接节点,以梅州为拓展节点,通过聚合—扩散效应,形成粤东旅游发展的双核联动模式;并以厦深铁路为发展轴,对接两边的珠三角旅游区和厦漳泉闽三角旅游区,尽快实现有效合作,才能避免成为旅游过境地。这一研究对于类似结构地区的旅游业发展也具有一定的借鉴作用。  相似文献   
设为首页 | 免责声明 | 关于勤云 | 加入收藏

Copyright©北京勤云科技发展有限公司  京ICP备09084417号