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21.
《Energy Policy》2015
This paper examines the factors determining household adoption of energy efficiency eco-innovations. We do so by testing hypotheses grounded in diffusion and finance theory and the literature on the barriers to energy efficiency. Using two large surveys of UK households, we explore the adoption of nine technologies. Our results indicate ‘investment inefficiency’ amongst household adopters occurs for two reasons. First, contrary to notions of rational choice, we find a negative relationship between the investment return of technologies and their level of diffusion. Second, we show adopters of these technologies display characteristics broadly consistent with diffusion theory, contradicting the prediction of finance theory that investment return, not individual characteristics, should drive adoption. We also find that policy has played a role in inducing the diffusion of these technologies and that tenure and spill-over effects are important in adoption. Finally, adoption is motivated more by a desire to save money than by environmental concern. We conclude by giving examples of how our research can lead to better policy timing and targeting. 相似文献
22.
The current state of cogeneration in Russia is analyzed. It is characterized by a sharp decrease in industrial heat consumption and a reduction in the demand for electricity. As a result many cogeneration plants presently operate under off-design conditions, which change their economic indexes to the worse. The ways of introducing small-scale cogeneration installations are considered, which show promise under the existing conditions of limited investments. The problems that accompany the introduction of modern highly efficient large-capacity power units at cogeneration plants are analyzed. 相似文献
23.
Study and optimization of the thermal performances of the offset rectangular plate fin absorber plates, with various glazing 总被引:1,自引:0,他引:1
The low thermophysical characteristics of air used as a heat transfer fluid in the solar collectors with thermal conversion require a fully developed turbulent flow. This increases the thermal heat transfer between the absorber plate and the fluid, which clearly improves the thermal performances of the solar collector with obstacles arranged into the air channel duct. In the present work, we introduce, in solar collector, the offset rectangular plate fins, which are used in heat exchangers. An experimental investigation carried out showed the generated enhancement of thermal performance. The offset rectangular plate fins, mounted in staggered pattern, are oriented parallel to the fluid flow and are soldered to the underside of absorber plate. They are characterized by high heat transfer area per unit volume. High thermal performances are obtained with low pressure losses and in consequence a low electrical power consumption by the fan in comparison to the flat plate collector. The experimental results are all so compared by using two types of transparent cover; double and triple. 相似文献
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《电子学报:英文版》2016,(5):986-990
A 320-356GHz fixed-tuned frequency doubler is realized with discrete Schottky diodes mounted on 50μm thick quartz substrate.Influence of circuit channel width and thermal dissipation of the diode junctions are discussed for high multiplying effficiency.The doubler circuit is flip-chip mounted on gold electroplated oxygenfree copper film for grounding of RF and DC signals,and better thermal transportation.The whole multiplying circuit is optimized and established in Computer simulation technology (CST) suite.The highest measured multiplying efficiency is 8.0% and its output power is 5.4mW at 328GHz.The measured typical output power is 4.0mW in 320-356GHz. 相似文献
26.
针对超宽带功率放大器(UWB PA)匹配电路的设计难点,提出一种结合连续型功放理论、多谐波双向牵引低损耗匹配(LLM)技术以及切比雪夫低通滤波器阻抗变换原理的超宽带功率放大器设计方法。并利用此方法设计一款基于CREE公司CGH40025F-Ga N HEMT,工作频带为400-3900MHz的超宽带功率放大器。实验结果表明:在输入功率为30d Bm(1W)时,增℃为12.25±0.75dB,输出功率大于41.5dBm(14.1W),功率附加效率(PAE)为41-65.1%,噪声系数(NF)控制在2.5dB以内,功率附加效率较同等带宽设备有近10%的提升。 相似文献
27.
提高信道的数据传输效率是人们不断追求的目标之一,也是衡量网络性能的标准之一,从几方面分析总结了为此而采取的各种措施。 相似文献
28.
125 MW 机高压前轴封漏汽量的测量计算及中压缸效率核算 总被引:2,自引:1,他引:2
介绍了莱芜电厂2号机改造后高压前轴封漏汽量测量原理和方法,计算出高压前轴封漏汽量,并代入热力性能试验计算过程中,核算了除掉轴封漏汽量影响的中压缸效率。此计算方法和图表普遍适用于125MW机组高压前轴封漏汽量的计算。 相似文献
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