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991.
Improving access to more modern forms of energy requires supply chains that reach further into rural areas. This paper studies a supply-side intervention intended to foster last-mile distribution of energy-access technologies through local small-scale entrepreneurship. We use a staggered-implementation evaluation design to assess the impact on employment and income outcomes of the intervention, which is a large-scale program in Kenya that supports the diffusion of improved cookstoves and small solar products. The results demonstrate how trained entrepreneurs intensify and diversify their income-generating activities, often by shifting away from subsistence farming as a main source of income. For cookstove entrepreneurs, this goes along with improvements in individual and household incomes as well as perceived economic well-being. Our estimates suggest that impacts do not only differ between the two technologies but also across subgroups including gender, age, and baseline occupation. Our findings substantiate that market-based interventions can foster energy access in rural areas by supporting the establishment of local businesses. We highlight several contextual factors that are of relevance when considering the adoption of this approach.  相似文献   
992.
基于湖北省382份茶叶种植户调研数据,采用随机前沿生产函数模型“一步估计”法分析贫困山区农户茶叶生产技术效率和影响因素。研究结果表明:样本户茶叶种植存在较大改进空间;样本户资本和劳动力投入剩余;茶园的海拔、树龄、茶农是否加入合作社、种植面积、户主是否受过种茶培训等因素对农户茶叶生产技术效率有重要影响。因此,提出紧抓乡村振兴战略机遇,推动贫困山区茶产业高质量发展;建立茶产业“三项补贴”,改善茶园基础设施条件;优化茶叶种植布局,提高合作社服务水平;成立茶产业发展基金,加快培育职业茶农,以提高贫困山区农户茶叶生产技术效率。  相似文献   
993.
Data Envelopment Analysis (DEA) window analysis with ideal window width is applied to evaluate the green technology innovation efficiency of 28 manufacturing industries in China during 2006–2014. The obtained results are compared with those calculated using the traditional DEA model, and convergence analysis of the efficiency is conducted. Five years is the obtained ideal window width and DEA window analysis with ideal window produces results closer to reality for China's manufacturing industry. The overall efficiency of the green technology innovation in the manufacturing sector is low following a wave-shaped curve – first decreasing, then increasing and decreasing again, with large inter-industrial differences. There are 8 high-, 14 medium- and 6 low-efficiency industries. A convergence trend in the green technology innovation efficiency within the 28 manufacturing industries exists, implying a catch-up effect between them.  相似文献   
994.
本文以生产要素内部配置结构调整对边际产出弹性影响为基础,建立包含生产要素内部配置结构的科布-道格拉斯生产函数,对中国工业企业技术创新效率进行实证分析。主要结论有:区域外商投资工业企业比例的增加能提升资本和劳动力边际产出弹性;区域内资工业企业比例的增加能提升劳动力边际产出弹性;政府科技资助与工业企业技术创新效率之间并非简单的线性关系。提高工业企业技术创新效率需要政府科技资助形成一定规模;劳动者素质提高对工业企业技术创新效率产生积极影响。政策建议是:继续加大对外开放力度,优化区域生产要素配置结构;扩大政府科技资助规模,优化政府科技资助结构;有效引导高素质人才流动。  相似文献   
995.
以浙江电网企业转型现代能源综合服务的具体战略与发展规划为研究背景,针对能源综合服务系统的运行规划目标,开展基于运行规划的能源综合服务系统能效管理研究。从系统工程的视角出发,以能源流为纽带,基于多尺度能源系统建模方法,构建了能源综合服务系统模型,并结合系统综合能效,采用粒子群优化算法来优化系统各设备单元的运行策略,以实现基于运行规划的最优能效管理。通过能源综合服务系统模型计算表明,大规模清洁能源和可再生能源的接入,可以明显提高系统综合能效;随着区域用户总冷量和/或总热量需求占总电力需求的比值增大,系统最优综合能效逐渐增大;与使用内燃机、燃气轮机及汽轮机为原动机的热电联产系统相比,使用燃料电池为原动机的热电联产系统可以使能源综合服务系统综合能效更优。  相似文献   
996.
The aim of the paper is to identify which among the aspects that relate to the composition of the student body, school (district) size, management practices and the school principals' own characteristics are associated with the performance of Italian students at grade 8, measured through standardised test scores in reading and mathematics. The analysis makes use of a student-level efficiency model, and several school level variables are included as explanators for efficiency scores. The results show that, especially for reading, the most influential variables relate to the composition of the student body, while the students' performance in mathematics is partly correlated with the management practices adopted by the school principal/head teacher. Schools and schooling can only explain a minor part of the variance in achievement scores, however, and the characteristics of the students themselves play the most significant role.  相似文献   
997.
We study the implementation of a time-varying pricing (TVP) program by a major electricity utility in Costa Rica. Because of particular features of the data, we use recently developed understanding of the two-way fixed effects differences-in-differences estimator along with event-study specifications to interpret our results. Similar to previous research, we find that the program reduces consumption during peak-hours. However, in contrast with previous research, we find that the program increases total consumption. With a stylized economic model, we show how these seemingly conflicted results may not be at odds. The key element of the model is that previous research used data from rich countries, in which the use of heating and cooling devices drives electricity consumption, but we use data from a tropical middle-income country, where very few households have heating or cooling devices. Since there is not much room for technological changes (which might reduce consumption at all times), behavioral changes to reduce consumption during peak hours are not enough to offset the increased consumption during off-peak hours (when electricity is cheaper). Our results serve as a cautionary piece of evidence for policy makers interested in reducing consumption during peak hours—the goal can potentially be achieved with TVP, but the cost is increased total consumption  相似文献   
998.
[目的]小麦是我国重要的口粮之一,提高小麦的技术效率对于保障粮食安全具有重要的战略意义。在测算小麦技术效率的基础上,找出影响小麦技术效率的关键因素,为保障国家口粮安全提供参考。[方法]基于调研数据,运用超越对数生产函数以及一步随机前沿分析方法,构建计量模型分析土地细碎化和土地质量对小麦技术效率的影响。[结果]全部样本的技术效率差距较大,规模经营农户的技术效率高于小农户,农户技术效率最高的种植面积为67~333hm2,代表小麦种植的适宜规模。从技术效率的影响因素来看,土地细碎化程度和土地质量都对小麦生产的技术效率产生显著影响。[结论]为了提高小麦的技术效率,应该发展多种形式适度规模经营,鼓励创新土地流转形式,提高农业机械化水平; 深入开展土地质量调查,因地制宜地选择土地修复路径; 实行精准补贴,切实保护农民的利益。  相似文献   
999.
虽然远程交流技术快速发展,但现有研究表明专利发明在很大程度上仍依赖于信息的地理邻近。以中国1992-2009年的1 331个新能源发明专利为研究对象,运用Jung Wonn,Jaffe等的实验设计方法,研究了专利引证的地理邻近是否会随时间递进而增大。结果表明,个人、大学、公司及其它种类发明专利引证的地理邻近会随着时间变化而增大,而政府受到的影响较小。另外,由于区域城市分属不同省份,因此并不能证明区域专利引证的地理邻近也会随着时间变化而增大。  相似文献   
1000.
Many models have been studied for forecasting the peak electric load, but studies focusing on forecasting peak electric load days for a billing period are scarce. This focus is highly relevant to consumers, as their electricity costs are determined based not only on total consumption, but also on the peak load required during a period. Forecasting these peak days accurately allows demand response actions to be planned and executed efficiently in order to mitigate these peaks and their associated costs. We propose a hybrid model based on ARIMA, logistic regression and artificial neural networks models. This hybrid model evaluates the individual results of these statistical and machine learning models in order to forecast whether a given day will be a peak load day for the billing period. The proposed model predicted 70% (40/57) of actual peak load days accurately and revealed potential savings of approximately USD $80,000 for an American university during a one-year testing period.  相似文献   
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