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11.
400W行波热声发电系统的实验研究   总被引:1,自引:0,他引:1  
本文阐述了为太阳能发电系统设计的400 W行波热声发电系统(TWTAEG)的实验研究过程.实验系统由行波热声发动机和直线发电机组成,系统采用平均压力为3.5 MPa的氦-氩混合气体为工质,其中氩气分压比为1.4%,系统运行频率为74Hz.实验中最大输出电功为446 W,此时的热电效率为13%;在输出电功为416 W时热...  相似文献   
12.
Fine features of gamma-ray radiation registered during a thunderstorm at Tien-Shan Mountain Cosmic Ray Station are presented. Long duration (100-600 ms) gamma-ray bursts are found. They are for the first time identified with atmospheric discharges (lighting). Gamma-ray emission lasts all the time of the discharge and is extremely non-uniform consisting of numerous flashes. Its peak intensity in the flashes exceeds the gamma-ray background up to two orders of magnitude. Exclusively strong altitude dependence of gamma radiation is found. The observation of gamma radiation at the height 4-8 km could serve as a new important method of atmospheric discharge processes investigation.  相似文献   
13.
介绍了福建省目前的分时电价政策.基于冷库实例,模拟计算了制冷装置增加夜间运行时间,采用不同蓄冷运行方案的运行费用.结果显示,理想条件下冷库的运行电费可节省47.3%以上,现场调研的某冷库运行电费可减少约31%.根据气象台的逐时气象数据统计,厦门市夜间湿球温度下降1.2~1.8℃.计算表明,制冷装置夜间运行的COP因此比...  相似文献   
14.
The self‐adaptive intelligence gray predictive model (SAIGM) has an alterable‐flexible model structure, and it can build a dynamic structure to fit different external environments by adjusting the parameter values of SAIGM. However, the order number of the raw SAIGM model is not optimal, which is an integer. For this, a new SAIGM model with the fractional order accumulating operator (SAIGM_FO) was proposed in this paper. Specifically, the final restored expression of SAIGM_FO was deduced in detail, and the parameter estimation method of SAIGM_FO was studied. After that, the Particle Swarm Optimization algorithm was used to optimize the order number of SAIGM_FO, and some steps were provided. Finally, the SAIGM_FO model was applied to simulate China's electricity consumption from 2001 to 2008 and forecast it during 2009 to 2015, and the mean relative simulation and prediction percentage errors of the new model were only 0.860% and 2.661%, in comparison with the ones obtained from the raw SAIGM model, the GM(1, 1) model with the optimal fractional order accumulating operator and the GM(1, 1) model, which were (1.201%, 5.321%), (1.356%, 3.324%), and (2.013%, 23.944%), respectively. The findings showed both the simulation and the prediction performance of the proposed SAIGM_FO model were the best among the 4 models.  相似文献   
15.
本给出了一种验证楞次定律实验现象的良好方法,可以明显观察到线圈中突然通以电流时产生的电磁冲击力。  相似文献   
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17.
W/O型乳胶粒子表面电性的近代测试技术   总被引:1,自引:0,他引:1  
采取近代表面电学测试技术对乳胶粒子表面电性进行微观测量,取得了一系列反映胶粒表面双电层结构的特征参量,证明表面扩散双电层的存在。为完善W/O型乳胶体系的稳定性理论提供了一定实验依据。  相似文献   
18.
We use agent-based simulation in a coordination game to analyse the possibility of market power abuse in a competitive electricity market. The context of this was a real application to the England and Wales electricity market as part of a Competition Commission Inquiry into whether two particular generators could profitably influence wholesale prices. The research contributions of this paper are both in the areas of market power and market design policy issues for electricity markets, and in the methodological use of large industry-wide evolutionary simulation models.  相似文献   
19.
We propose and apply a novel approach for modeling special-day effects to predict electricity demand in Korea. Notably, we model special-day effects on an hourly rather than a daily basis. Hourly specified predictor variables are implemented in the regression model with a seasonal autoregressive moving average (SARMA) type error structure in order to efficiently reflect the special-day effects. The interaction terms between the hour-of-day effects and the hourly based special-day effects are also included to capture the unique intraday patterns of special days more accurately. The multiplicative SARMA mechanism is employed in order to identify the double seasonal cycles, namely, the intraday effect and the intraweek effect. The forecast results of the suggested model are evaluated by comparing them with those of various benchmark models for the following year. The empirical results indicate that the suggested model outperforms the benchmark models for both special- and non-special day predictions.  相似文献   
20.
加大供电量和提高电费回收效率是供电商增加收益的主要途径,并且用电客户的缴费时间差直接影响着电费回收效率。在用电客户信息较少的情况下,仅仅依赖用电客户的用电量信息和缴费时间差信息,采用扩展的“S型”函数对用电量信息和缴费时间差信息进行整合建模,构建了一个能够度量客户持续用电能力和缴纳电费积极性的客户信用动态评价模型。应用构建的模型对赤峰市宁城县实际用电客户进行信用评价,评价结果与领域专家评价结果具有较高的一致性。  相似文献   
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