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81.
Mobilising under-utilised low carbon (ULC) land resources for future agricultural production can help reducing pressure on high carbon stock land from agricultural expansion, particularly for deforestation hotspots like Kalimantan. However, the potential of ULC land is not yet well understood, especially at regency level which is the key authority for land-use planning in Indonesia. Therefore, this study explored ULC land resources for all regencies in Kalimantan. By analysing information from six monitoring domains, a range of indicators were derived to provide insights into the physical area of ULC land from various perspectives. It was found that these indicators show largely different values at regency level. For example, regency Pulang Pisau has a substantial area of ‘temporarily unused agricultural land’ but a very limited area of ‘low carbon land’ – this implies that not all ‘temporarily unused agricultural land’ is ready for future exploitation when assessing from different aspects. As a result of such diverging indicators, using a single indicator to quantify available ULC land resources is risky as it can either be an over- or under-estimation. Thus, ULC land resources were further explored in the present paper by taking four regencies as case studies and comparing all the indicators, supported with relevant literature and evidence collected from narrative interviews. This information was used to estimate ULC land area by possible land-use strategies. For example, Gunung Mas was found to have a large area of low carbon land which is not occupied and might be suitable for oil palm deployment. However, the major limitation is that physical estimates cannot provide a complete picture of ‘real’ land availability without considering a broader range of socio-economic factors (e.g. labour availability). Therefore, physical land area indicators from different domains must be combined with other qualitative and quantitative information especially the socio-economic factors underlying land under-utilisation to obtain better estimates.  相似文献   
82.
西部大开发后西部地区经济增长加快、人民生活水平提高,但产业结构、技术水平以及生态环境质量却并未表现出同等程度的改善或提升。采用30个样本省份1995—2011年的面板数据,运用双重差分法进行分析,结果发现:西部大开发在促进西部地区经济增长以及地区经济趋同的同时,也使得西部地区的碳排放(尤其是人均碳排放)与其他地区相比增长更快,与此同时,西部地区与碳排放相关的因素和条件(如产业结构、技术水平、市场化程度等)未得到显著改善。在既有的资源禀赋、发展阶段、产业结构以及经济发展方式下,西部大开发初期着力于固定资产投资和资源、能源开发,忽视教育事业、市场化改革、技术创新等软环境建设,导致西部地区在经济增长的同时碳排放相对增加。因此,在今后的西部大开发规划中,应当着力于转变经济发展方式,加强软环境建设,重视人力资本积累和技术创新,提升市场化水平,才能在发展地区经济的同时实现节能减排。  相似文献   
83.
研究目的:从系统角度分析土地、人口、社会、经济、能源对碳排放的影响作用,并对武汉市2017—2030年不同政策情景下的土地利用碳排放进行模拟,为其低碳发展战略和低碳土地利用规划提供决策依据。研究方法:系统动力学方法。研究结果:(1)建立的城市土地利用碳排放系统动力学模型是有效的;(2)按照目前的发展趋势,武汉市的碳排放总量将保持逐年攀升的趋势;(3)经济的快速发展对武汉市土地利用碳排放量的增加具有显著的影响作用;(4)调整土地利用结构、调整产业结构以及提高能源利用效率都能够有效的减少武汉市土地利用碳排放量,其中调整土地利用结构和调整产业结构的作用效果相对来说更加明显。研究结论:转变经济增长方式、升级产业结构、调整土地利用结构和积极研发先进的低碳科学技术是武汉市低碳发展的重要途径。  相似文献   
84.
人类的生活方式是与其社会的文明状态相适应的。原始文明社会中人类的生活方式是“朴素无碳”的,农业文明社会中人类的生活方式是“适应性低碳”的,工业文明社会中人类的生活方式是“发展性高碳”的,而生态文明社会中人类的生活方式应是“理性低碳”的。理性低碳生活方式是人类可持续发展的自我选择,是要在提高生活水平和质量的进程中实现低碳化,是生活方式的革命性发展。构建和普及理性低碳生活方式,需要树立和强化低碳生活理念,实现衣食住行等多方面的低碳化改造;需要全人类的共同努力,各个国家和地区应根据实际情况选择和普及各具特色的理性低碳生活方式;需要各生活主体的协同配合,政府、企业与居民等要全方位地、积极地、广泛地践行理性低碳生活方式。  相似文献   
85.
研究目的:针对快速城镇化地区农户生计分化现象,以上海市青浦区为例,对不同生计策略类型农户的耕地利用集约度进行评价,并分析其影响因素,以期为改善农户土地利用行为、实现土地资源合理高效利用与农户生计可持续发展提供政策参考。研究方法:运用价值形态测度方法核算各生计类型农户的耕地利用集约度,以两水平方差成分模型确定耕地利用集约度影响因素。研究结果:(1)不同生计策略类型农户耕地利用集约度存在差异性,大小顺序依次为专业农业型、传统农业型、农业兼业型、非农兼业型,劳动集约度与资本集约度排序与之基本一致;(2)同一生计策略类型农户的耕地利用集约度存在相似性,耕地利用集约度的总变异中有24.32%是由农户生计策略类型不同而引起的,水平一中农业收入比重、农业补贴、耕地面积、地块平均离家距离、农户离集镇距离与水平二中是否兼业等是影响农户耕地利用集约度的显著因素;(3)模型拟合效果评价表明该方法具有可行性。研究结论:耕地利用集约度不仅与农户自身禀赋有关,而且受生计类型影响,政府相关部门应结合当地实际情况引导农户对这两方面进行调整或完善。  相似文献   
86.
我国农作物秸秆综合利用现状及焚烧碳排放估算   总被引:19,自引:0,他引:19  
[目的]为加快推进秸秆资源化利用工作,有效缓解因秸秆焚烧带来的环境问题。[方法]将全国划分为黄淮海区、西北区、东北区、东南区、西南区五大区域,对各类农作物秸秆进行了统计分析,研究了秸秆产生量、秸秆资源密度、秸秆利用结构、秸秆焚烧碳排放量。[结果]全国秸秆理论资源量达到10.4亿t,可收集量达到9.0亿t,玉米、水稻和小麦3类农作物秸秆占总量的79.19%,黄淮海区秸秆产量最高,占总量的33.41%。秸秆已利用量为7.21亿t,综合利用率达到80.11%,其中肥料化、饲料化、基料化、燃料化、原料化利用量占已利用量的比例分别为53.93%、23.42%、4.98%、14.27%、3.40%,形成了农用为主的利用格局,但不同秸秆种类综合利用率和利用结构存在显著差异。全国秸秆资源密度和人均占有量分别为523.57kg/667m~2和1.75 t,东北区显著高于全国平均水平,西南区和东南区则显著低于全国平均水平。根据环保部卫星遥感监测的露天焚烧火点数比例估算,2015年我国秸秆露天焚烧量约为8 110万t,总碳排放量约为3 450万t,其中东北地区约占74.1%。[结论]我国秸秆综合利用的重点和难点在东北地区,进一步推动区域秸秆实现全量利用,对于促进低碳农业发展,应对气候变化有着十分重要的意义。  相似文献   
87.
We consider a framework for solving optimal liquidation problems in limit order books. In particular, order arrivals are modeled as a point process whose intensity depends on the liquidation price. We set up a stochastic control problem in which the goal is to maximize the expected revenue from liquidating the entire position held. We solve this optimal liquidation problem for power‐law and exponential‐decay order book models explicitly and discuss several extensions. We also consider the continuous selling (or fluid) limit when the trading units are ever smaller and the intensity is ever larger. This limit provides an analytical approximation to the value function and the optimal solution. Using techniques from viscosity solutions we show that the discrete state problem and its optimal solution converge to the corresponding quantities in the continuous selling limit uniformly on compacts.  相似文献   
88.
We examine the role of inventories and capacity utilization (of both capital and labor) for the propagation of business cycle fluctuations. We document a new set of facts regarding the U.S. cyclical regularities of inventories and capacity utilization. First, we find that capital utilization and the flows of services from both capital and labor are procyclical, and comove with the holdings of inventories. Second, we find that labor utilization is procyclical as well, but is weakly negatively correlated with inventories. We build a model that accounts for these facts, and also accounts for the stylized inventory facts, i.e., inventory holdings are procyclical, while the inventory-to-sales ratio is countercyclical. The analysis is centered on the effects of two possible shocks: preference (demand) shocks and technology shocks. Our model shows that inventories and the rate of capital utilization are mostly complements, while inventories and the rate of labor utilization are mostly substitutes. It further shows that temporary demand shocks emphasize the role of inventories as being a “shock absorber,” whereas high-persistence demand shocks, as well as technology shocks of any persistence, emphasize the role of inventories as being a complement to consumption.  相似文献   
89.
With corporate disclosure of carbon emissions rapidly increasing, the long-standing question remains whether carbon disclosure has any influence on the improvement of carbon performance. Previous studies of environmental disclosure and performance have predominantly focused on whether disclosure is a substitute for poor performance. Little attention has been devoted to the more important question about how changes in disclosure may lead to subsequent changes in performance over time. Following the rationales taken by the legitimacy and management perspectives, we revisit the relationship between carbon disclosure and performance, with a focus on changes that disclosure may (or may not) create. Using a change analysis of Global 500 companies and their carbon emission and disclosure data released between 2008 and 2012, this study finds that the change in carbon disclosure levels is positively associated with a subsequent change in carbon performance (examined through direct and indirect carbon emission intensities). Thus, regardless of whether disclosure has been used as a legitimising tool for prior poor performance, this study confirms that carbon disclosure motivates companies and creates an ‘outside-in’ driven effect for subsequent change and improvement in carbon performance. However, the association between changes in carbon disclosure and performance is relatively weaker in high energy-intensive firms.  相似文献   
90.
This paper empirically assesses the relevance of information on corporate climate change disclosure and performance to asset prices, and discusses whether this information is priced appropriately. Findings indicate that corporate disclosures of quantitative greenhouse gas (GHG) emissions and, to a lesser extent, carbon performance are value relevant. We use hand‐collected information on quantitative GHG emissions for 433 European companies and build portfolios based on GHG disclosure and performance. We regress portfolios on a standard four factor model extended for industry effects over the years 2005 to 2009. Results show that investors achieved abnormal risk‐adjusted returns of up to 13.05% annually by exploiting inefficiently priced positive effects of (complete) GHG emissions disclosure and good corporate climate change performance in terms of GHG efficiency. Results imply that, firstly, information costs involved in carbon disclosure and management do not present a burden on corporate financial resources. Secondly, investors should not neglect carbon disclosure and performance when making investment decisions. Thirdly, during the period analysed, financial markets were inefficient in pricing publicly available information on carbon disclosure and performance. Mandatory and standardised information on carbon performance would consequently not only increase market efficiency but result in better allocation of capital within the real economy.  相似文献   
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