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71.
Valuing ecosystem services: A shadow price for net primary production   总被引:4,自引:0,他引:4  
We analyze the contribution of ecosystem services to GDP and use this contribution to calculate an empirical price for ecosystem services. Net primary production is used as a proxy for ecosystem services and, along with capital and labor, is used to estimate a Cobb Douglas production function from an international panel. A positive output elasticity for net primary production probably measures both marketed and nonmarketed contributions of ecosystems services. The production function is used to calculate the marginal product of net primary production, which is the shadow price for ecosystem services. The shadow price generally is greatest for developed nations, which have larger technical scalars and use less net primary production per unit output. The rate of technical substitution indicates that the quantity of capital needed to replace a unit of net primary production tends to increase with economic development, and this rate of replacement may ultimately constrain economic growth.  相似文献   
72.
The North-America Free Trade Agreement (NAFTA) has brought together the economies of Canada, Mexico, and the US into forming one of the largest trading blocs worldwide (within the top CO2 emitters). However, the current global protectionist discourse threatens the agreement. This paper analyzes the energy and energy-related CO2 emission relationships between NAFTA countries in 2014 to gain insights into the climate change implications of current integration and the possible cancelation of the agreement. The analysis is performed with a multi-regional version of the multi-factor energy input–output model. The results show that NAFTA has not built a single integrated energy system, though it has helped reduce energy-related CO2 emissions. Moreover, if NAFTA is not revoked, further integration would depend on the capacity of the Mexican energy sector to converge to the performance of its trade partners’ energy sectors. Conversely, a broken deal would induce negative environmental externalities.  相似文献   
73.
The paper describes non‐parametric approach for analysis of a three‐period, two‐treatment, four‐sequence crossover design in which test procedure for interchangeability of the treatment effects is obtained. The proposed procedure is based on a non‐parametric model, which incorporates, along with the direct treatment effects and the usual carryover effects, the long‐term carryover effects. Relevant competitors are obtained. Related asymptotic results are given. By performing simulation study, we compared the procedures with respect to type I error rate and power. Furthermore, confidence intervals for treatment differences are studied. The procedures are illustrated with a data study.  相似文献   
74.
基于变电站主设备服役周期长、运维费用高、故障风险大、残值高等特点,在变电站主设备全寿命周期费用结构分解的基础上,结合动态成本计算模型,重点构建了变电站主设备LCC招标评标动态模型,并应用于变电站主设备的招标评标打分计算。最后,通过特高压工程1000KV变压器招标采购算例,验证说明了LCC招标评标动态模型能全面反映变电站主设备的全寿命周期成本费用,有助于从源头上统筹处理好安全、效能和周期成本三者的关系,有助于最优采购方案的选取。  相似文献   
75.
辽宁省农产品电子商务发展对策分析   总被引:1,自引:0,他引:1  
文章运用SWOT方法分析了辽宁省农产品电子商务的应用现状,运用SPSS软件进行了电子商务与第一产业关系的实证研究,并在此基础上提出了有针对性的对策建议。  相似文献   
76.
我国区域经济发展态势分析与展望   总被引:1,自引:0,他引:1  
李宪  刘勇 《开放导报》2008,(3):32-37
2007年我国中西部地区经济增长速度首次超过东部地区,区域经济继续保持普遍加速高位运行态势,地区差距继续向趋缓方向发展:增长速度继续呈"西部东部快、中部慢"格局,差距继续有所缩小;经济总量继续呈"东部大、中西部小"格局,总量比重结构差距呈"地带缩小、省区拉大"态势。2008年我国区域经济将继续保持良好发展趋势,增长速度可能稍有放缓,区域差距将继续保持"绝对差扩速放缓、相对差距略有缩小"态势。本文提出了2008年区域经济协调发展的若干对策建议。  相似文献   
77.
在当代中国,坚持发展是硬道理的本质要求,就是坚持科学发展。从我国现阶段的基本国情和"十二五"规划的主题看,发展仍是我们解决所有问题的关键所在。  相似文献   
78.
This article reports on one outcome from a three-year study with pre-service primary teachers at Goldsmiths' College, University of London. The purpose of the study was to evaluate the influence of participants' prior educational experience and beliefs about the relationship between design & technology (D&T) and science on their lesson planning for these subjects during school placements. Data from the study support a three-domain model of pre-service teachers' thinking and action. When operating within the pragmatic domain, participants are primarily concerned with survival in the classroom, resulting in short-term planning which may contradict their epistemological and curricular beliefs. In the pedagogical domain, the focus shifts from the pre-service teacher themselves and their immediate survival to the learning potential of the activities they plan. There is evidence that some participants have progressed to operating within a philosophical domain, leading to clasroom practice which reflects and re-conceptualises pre-service teachers' core beliefs about the nature of, and relationship between, D&T and science. This revised version was published online in July 2006 with corrections to the Cover Date.  相似文献   
79.
This paper describes the frameworks and cognitive tools that have been developed to enhance practising teachers' pedagogical content knowledge in primary school technology education. The frameworks evolved from our research that firstly examined existing teaching practices, secondly enhanced formative interactions and thirdly enhanced summative assessment strategies. The evidence gained over the three years demonstrated how the effective use of frameworks could be utilised to enhance teacher pedagogical content knowledge (PCK). How we see learning is of prime importance in examining the development of teacher pedagogical content knowledge. A sociocultural view of learning is taken where human mental processes are situated within their historical, cultural and institutional setting. In the research project we strongly emphasised the need for teachers to build a knowledge base for teaching technology. Critical aspects identified as enhancing PCK included: negotiated intervention, planning frameworks, reflection on case studies, workshops and support in classrooms, appropriate resources, teacher agreement meetings, portfolios of student work and summative profiles. The increased PCK resulted in: enhanced teacher knowledge about technology including the nature of technology, areas of technology and specific technological knowledge, changed pedagogical approaches, enhanced teacher student interaction, refinement of appropriate learning outcomes, critical decision making, improved teacher confidence, and enhanced student learning. Seven characteristics or features of pedagogical content knowledge that we believe are important for effective teaching and learning in technology are presented. This revised version was published online in July 2006 with corrections to the Cover Date.  相似文献   
80.
Abstract

This study investigated the importance given by two groups of pre-service teachers of primary education from Spain and Portugal to seismic risk in a framework of different natural risks, both in personal terms and as future teachers. A questionnaire was used for data collection. Some questions about the seismic phenomenon were also included. The sample groups consisted of 110 students from an institution in Spain and 121 from one in Portugal. Both institutions are in cities affected by the historic Lisbon earthquake of 1755. The results showed that the risk of forest fire was the first choice for classroom study in both cases. The Spanish group was also more focused on the importance of other risks like flood and drought. The Portuguese group showed a greater concern with seismic risk, frequently referring to their own historic earthquake of 1755. A few gaps in knowledge concerning earthquake prediction and comparing seismic risk in different regions of their own countries were also found. In accordance with the results, it is suggested that training courses for primary school teachers should include Disaster Risk Education in Science Education for a better understanding of the impact of various hazards and a greater concern with seismic risk due to its particular features, especially in regions where the seismic pattern is characterized by long seismic cycles with major earthquake episodes.  相似文献   
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