全文获取类型
收费全文 | 4601篇 |
免费 | 279篇 |
国内免费 | 52篇 |
专业分类
财政金融 | 121篇 |
工业经济 | 509篇 |
计划管理 | 1006篇 |
经济学 | 1110篇 |
综合类 | 377篇 |
运输经济 | 27篇 |
旅游经济 | 45篇 |
贸易经济 | 361篇 |
农业经济 | 739篇 |
经济概况 | 637篇 |
出版年
2024年 | 10篇 |
2023年 | 77篇 |
2022年 | 89篇 |
2021年 | 133篇 |
2020年 | 143篇 |
2019年 | 104篇 |
2018年 | 94篇 |
2017年 | 136篇 |
2016年 | 156篇 |
2015年 | 181篇 |
2014年 | 378篇 |
2013年 | 389篇 |
2012年 | 462篇 |
2011年 | 586篇 |
2010年 | 436篇 |
2009年 | 285篇 |
2008年 | 250篇 |
2007年 | 228篇 |
2006年 | 188篇 |
2005年 | 135篇 |
2004年 | 83篇 |
2003年 | 87篇 |
2002年 | 67篇 |
2001年 | 64篇 |
2000年 | 47篇 |
1999年 | 38篇 |
1998年 | 12篇 |
1997年 | 11篇 |
1996年 | 9篇 |
1995年 | 24篇 |
1994年 | 4篇 |
1993年 | 6篇 |
1992年 | 6篇 |
1991年 | 2篇 |
1990年 | 3篇 |
1989年 | 1篇 |
1987年 | 1篇 |
1985年 | 1篇 |
1984年 | 5篇 |
1983年 | 1篇 |
排序方式: 共有4932条查询结果,搜索用时 15 毫秒
101.
Ioan Petri Haijiang Li Yacine Rezgui Yang Chunfeng Baris Yuce Bejay Jayan 《Enterprise Information Systems》2016,10(1):108-128
Recent research has emphasised that an increasing number of enterprises need computation environments for executing HPC (High Performance Computing) applications. Rather than paying the cost of ownership and possess physical, fixed capacity clusters, enterprises can reserve or rent resources for undertaking the required tasks. With the emergence of new computation paradigms such as cloud computing it has become possible to solve a wider range of problems due to their capability to handle and process massive amounts of data. On the other hand, given the pressing regulatory requirement to reduce the carbon footprint of our built environment, significant researching efforts have been recently directed towards simulation-based building energy optimisation with the overall objective of reducing energy consumption. Energy optimisation in buildings represents a class of problems that requires significant computation resources and generally is a time consuming process especially when undertaken with building simulation software, such as EnergyPlus. In this paper we present how a HPC based cloud model can be efficiently used for running and deploying EnergyPlus simulation-based optimisation in order to fulfil a number of objectives related to energy consumption. We describe and evaluate the establishment of such an application-based environment, and consider a cost perspective to determine the efficiency over several cases we explore. This study identifies the following contributions: (i) a comprehensive examination of issues relevant to the HPC community, including performance, cost, user perspectives and range of user activities, (ii) a comparison of two different execution environments such as HTCondor and CometCloud and determine their effectiveness in supporting simulation-based optimisation and (iii) a detailed performance analysis to locate the limiting factors of these execution environments. 相似文献
102.
This paper reports new evidence on the existence of both large and small price divergent clusters for China's energy markets, 2000–2009. The largest convergent price clusters suggest that the coal and gasoline markets are well integrated, however, small convergent price clusters suggest that electricity and diesel markets are proving harder to integrate. The paper argues that the traditional approach to price convergence analysis should be applied with caution, especially in a transitional economy such as China where questions to be asked should relate to the ‘degree of market‐orientation’ and not simply whether it is a market‐based economy or not. 相似文献
103.
China is the largest cement producer and consumer in the world. The cement industry’s rapid growth has led to a large demand of energy. This study reviews China’s cement industry in terms of energy intensity and examines the effects of technological progress on energy intensity. It also discusses the feasibility of achieving China’s energy reduction targets. We employ the Granger causality test and find that the total factor productivity or technological progress causes the energy intensity of the cement industry. Impulse responses analysis also proves that in the long run the technological change contributes to the decline in energy intensity of cement production. 相似文献
104.
Analysis of Shared and Sustainable Value Creation of Companies Providing Energy Solutions at the Base of the Pyramid (BoP) 下载免费PDF全文
Virgilio Panapanaan Tytti Bruce Terhi Virkki‐Hatakka Lassi Linnanen 《Business Strategy and the Environment》2016,25(5):293-309
This study was conducted to analyze the shared and sustainable value creation (SSVC) of 33 energy companies selling energy solutions at the base of the pyramid (BoP) markets. SSVC by selling energy technology solutions directed to address the cooking and lighting needs of BoP consumers were the main focus of analysis. Result showed that achieving profitability and affordability is affected by the kind of energy solution that is offered as well as the investment and level of commitment required. However, companies that fulfilled the profitable and affordable solutions were also able to deliver social and environmental sustainability benefits. Social sustainability benefits point to the ability of alleviating poverty by improving productivity or offering cost‐savings. Environmental sustainability benefits point to the energy savings. The findings show that inclusive business strategy is not necessarily required to reach the poor people profitably but a suitable business strategy depends on the type of energy solution. Copyright © 2014 John Wiley & Sons, Ltd and ERP Environment 相似文献
105.
This article applies a parametric metafrontier method and the Malmquist index to analyze the energy efficiency and its dynamic performance in China’s commercial sector from 1995 to 2013. The results indicate that the energy efficiency in China’s commercial sector is generally low, and there are significant regional differences and enormous energy-saving potentials. Relative to metafrontier, commercial sectors in eastern China have relatively higher energy efficiency; while those in central and western China have relatively low energy efficiency. Besides, the dynamic energy efficiency performance in China’s commercial sector has improved over the period. The technology improvement is a major driving factor to improve the energy efficiency in the commercial sectors of all the three regions. 相似文献
106.
Xian-Liang Tian 《The journal of international trade & economic development》2016,25(5):757-784
This paper first sets up a firm heterogeneity trade model and shows that given capital stock and productivity, export firms will have higher rates of capacity utilization. In addition, given capital stock and fixed export costs, firms with higher productivity are more likely to export. I then use the 2012 Chinese enterprise survey from the World Bank to empirically investigate the impact of participation in export on Chinese firms’ capacity utilization rate. The results show that on average, export firms have capacity utilization rate 1.55–2.01 percent higher than non-export firms, which amounts to 14.6–18.9 percent of the standard deviation of capacity utilization rate in the sample. I also find that firms with a larger part of shares owned by the government have lower capacity utilization. Stronger market competition leads to over-investment and therefore lower capacity utilization rate. Faced with more rigorous labor market regulation, firms will substitute capital for the use of labor, resulting in higher capacity utilization rate. 相似文献
107.
中国玉米芯资源量估算及其开发利用 总被引:2,自引:0,他引:2
文章首先采用文献考证法,确定玉米芯产量与玉米产量之比值;在此基础上,采用副产品比重法,结合玉米产量统计数据,对全国及各省(市、自治区)的玉米芯产量进行估算,并分析其区域分布;通过实地调查,结合文献综述,从原料化、饲料化、基料化、能源化的角度,系统阐述我国玉米芯资源综合利用途径。结果表明:玉米芯产量与玉米产量之比为0.21;2013年全国玉米芯资源总产量为4 590万t,相当于全国秸秆总产量的4.90%或玉米秸秆总产量的19.10%。主要分布于东北地区与黄淮海地区,产量分别为1 586.61万t与1 185.41万t,两地区合计占全国玉米芯产量的60.42%。玉米芯是我国各类秸秆资源中高值化利用率较高的种类,其原料化、基料化、饲料化及能源化利用总量达到800万t左右。食用菌基料化、新型能源化利用是提高我国玉米芯综合利用水平的基本途径。多产品联产可有效地促进我国玉米芯工业原料化利用水平的不断提升。积极开展玉米芯发酵饲料技术推广与应用可为我国玉米芯资源高值化利用开辟新途径。 相似文献
108.
节能生态农业技术扩散机制研究 总被引:1,自引:0,他引:1
程凌燕 《中国农业资源与区划》2016,37(4):134-137
如何处理好经济发展与节约资源、保护环境的关系成为我国未来发展迫待解决的问题之一,党的十八大更是对建设资源节约型、环境友好型社会提出了更新更高要求,农业与农村节能减排是我国《节能减排"十二五"规划》中的主要工作任务之一,其工作重点是大力推广科学高效的节肥、节药、节水、节能及农村废弃物资源化利用技术,以实现农业与农村经济快速可持续发展。当前我国各地区、各部门在国务院统一决策部署下,加大工作力度,采取积极有效的措施,推动了农业技术进步,更多的先进技术成果得到推广,节能减排工作初见成效。然而节能生态农业技术在应用范围上仍然有限,推进相关技术的扩散仍是节能减排工作中的重中之重。文章对农业技术扩散理论加以阐述,通过分析当前我国节能生态农业技术扩散现状,研究并探讨适合我国节能生态农业技术扩散的有效机制与具体举措,以期为提升我国资源节约型农业发展水平提供参考。 相似文献
109.
作为经济发展的源动力,能源及其安全测度问题一直是政府和学者研究的热门话题。将多样性引入到能源系统和能源安全研究中,探讨了能源安全和多样性之间的关系;界定了能源多样性的内容,包括国内能源供应的多样性和能源进口的多样性;利用香农-威纳多样性指数和Pielou均衡度指数,计算和分析了美国和中国近5年来的能源供应及进口情况,进而对其能源安全进行了对比研究。在2009—2013年,美国的能源多样性水平比中国高。结果表明能源多样性在一定程度上可以作为衡量能源安全的维度,中国能源多样性水平表明应致力于改变煤炭的主导局面,改善能源供应结构,拓宽和均衡能源进口渠道。 相似文献
110.
[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