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101.
在现有的家庭能量管理系统(Home Energy Management System,简称HEMS)的基础上增加分布式储能模块组成新的HEMS,并在此基础上提出了一种改进的基于0-1线性整数规划方法的家电最优调度模型。通过此调度模型,用户可以根据各自需求分别实现用电费用最省、用电费用最省同时兼顾满意度,或者二氧化碳排放最小的目标。该调度模型无论是在目标函数还是在约束条件上都采用线性化表示的方法,在使用极短的调度时间的同时能够保证调度结果是最优结果。最后通过仿真实验验证了提出方法的有效性以及验证了所提方法能够很好的应对电力公司的削峰填谷要求,具有重要的实际应用价值。实验结果表明,所提方法能够比以往相关研究取得更好地节约费用、减少二氧化碳排放的效果。 相似文献
102.
随着计算机交易系统在金融领域的深入运用,交易呈现出越来越多的风险.从计算机及网络技术的角度,提出了一种计算机交易系统风险监督体系.基于该体系,能够为银行、保险、证券、邮政、电信等行业的计算机交易系统提供"独立、实时、灵活"的风险监督管理系统,从而有效地保障了计算机交易系统在风险监督中的良性化运行. 相似文献
103.
Tomoharu?NakashimaEmail author Yasuyuki?Yokota Yukio?Shoji Hisao?Ishibuchi 《Artificial Life and Robotics》2007,11(2):145-148
We propose a genetic algorithm-based method for designing an autonomous trader agent. The task of the proposed method is to
find an optimal set of fuzzy if–then rules that best represents the behavior of a target trader agent. A highly profitable
trader agent is used as the target in the proposed genetic algorithm. A trading history for the target agent is obtained from
a series of futures trading. The antecedent part of fuzzy if–then rules considers time-series data of spot prices, while the
consequent part indicates the order of trade (Buy, Sell, or No action) with its degree of certainty. The proposed method determines the antecedent part of fuzzy if–then rules. The consequent
part of fuzzy if–then rules is automatically determined from the trading history of the target trader agent. The autonomous
trader agent designed by the proposed genetic algorithm consists of a fixed number of fuzzy if–then rules. The decision of
the autonomous trader agent is made by fuzzy inference from the time-series data of spot prices.
This work was presented in part at the 11th International Symposium on Artificial Life and Robotics, Oita, Japan, January
23–25, 2006 相似文献
104.
NO and N2O emissions from savanna soils following the first simulated rains of the season 总被引:2,自引:0,他引:2
M.C. Scholes R. Martin R.J. Scholes D. Parsons E. Winstead 《Nutrient Cycling in Agroecosystems》1997,48(1-2):115-122
Data on the emissions of oxides of nitrogen from the soil during the early part of the wet season are reported for nutrient-rich and nutrient-poor sandy soils at Nylsvley, South Africa. The emissions of NOx and N2O following the first wetting event of the season are elevated relative to subsequent events. The observed high emission rates (76 ng N-NO m-2 s-1) are partially attributed to the sandiness of the soil, which permits NO to diffuse out of the soil rapidly. The pulse of high emissions following wetting is maintained for approximately 72 hours, thereafter continuing at around 20 ng NO m-2 s-1 while the soil remains moist. The initial pulse is suggested to be due to the accumulation of a substrate pool during the dry period, coupled with an inability of plants and microbes to use it effectively during the first few days after wetting. There were no significant differences in the peak or subsequent emission rates for either NO or N2O between two sites of differing nitrogen mineralisation potentials. N2O emissions averaged 8% of NOx emissions. The enhanced emissions of NOx which follow the first wetting after a prolonged dry period do not make a very large contribution to the annual gaseous N emission budget, but could be a significant contributor to the high tropospheric ozone levels observed over southern Africa in springtime. 相似文献
105.
为了研究中国新兴产业市场股票价格的可预测性,提高投资收益率,借鉴Jegadeesh and Titman的方法,对样本区间内股票价格和成交量数据进行研究。结果表明:高成交量股票在短期内存在动量效应而长期内则表现为反转,低成交量股票在长期内表现为动量效应。 相似文献
106.
随着节能减排与能源高效利用的不断推进,基于能源综合利用的多能源联供系统解决了多种能源的供应问题,是供能技术发展的方向和趋势.结合目前相继出台的排污权交易(Emission Trading)机制,提出排污权交易下的多能源联供系统优化调度方式.首先分析完全竞争和寡头竞争市场模式下的排污权交易价格,通过理论分析获得多能源联供系统的排污权交易成本的数学期望.在此基础上,以系统成本最小为目标,考虑供需平衡约束以及能源平衡约束,提出多能源联供系统的优化调度模型,并运用非线性原一对偶内点算法求解该模型.最后,以具有热电联供特征的广东理文造纸有限公司为例说明所提出的优化调度方式的有效性和可行性. 相似文献
107.
对无交易机制、市场交易机制和政府主导交易机制3 种状态下水权交易的资源配置效率和节水效果进行了分析与比较。首先运用简单的个体决策模型来分析比较无交易机制状态和市场交易机制状态下的资源配置效率和节水效果;其次运用两阶段博弈模型分析政府主导交易机制下的个体最优决策所导致的资源配置效率和节水效果。分析结果表明在参与人目标收益最大化约束前提下,市场交易机制只能实现水资源的优化配置却不能促进节水,而政府主导交易机制在实现水资源优化配置上更有效率,而且在一定条件下可能促进节水。最后通过数值模拟演示了上述分析结构,并运用美国加州和德州的水权交易数据进一步验证了本文结论。 相似文献
108.
Xiaohu Yang Liping Zhao Xinyu Wang Ye Wang Jie Sun Albert Jerry Cristoforo 《Software》2012,42(2):131-157
Although quality requirements (QRs) have become a major drive in today's software development, there have been very few real‐world examples in the literature that demonstrate how to meet these requirements. This paper presents such an example. Specifically, the paper describes the design of a partition‐based distributed stock trading service system that satisfies a set of QRs related to resource utilization, performance, scalability and availability. The paper evaluates this design through detailed experiments and discusses some design alternatives and the lessons learned. Central to this design are a static load distribution strategy and a dynamic load balancing strategy. The first strategy is to achieve an initial balanced workload on the system's server cluster during the system initialization time, whereas the second strategy is to maintain this balanced workload throughout the system execution time. Together, these two strategies work in unison to ensure that the server resources are efficiently utilized; the user requests are processed with the required speed; the application is partitioned with sufficient room to scale; and the system is highly available. Copyright © 2011 John Wiley & Sons, Ltd. 相似文献
109.
Hao Zhou Jia Pei ZhaoLi Gang Zheng Chun Lin WangKe Fa Cen 《Engineering Applications of Artificial Intelligence》2012,25(1):147-158
Modeling NOx emissions from coal fired utility boiler is critical to develop a predictive emissions monitoring system (PEMS) and to implement combustion optimization software package for low NOx combustion. This paper presents an efficient NOx emissions model based on support vector regression (SVR), and compares its performance with traditional modeling techniques, i.e., back propagation (BPNN) and generalized regression (GRNN) neural networks. A large number of NOx emissions data from an actual power plant, was employed to train and validate the SVR model as well as two neural networks models. Moreover, an ant colony optimization (ACO) based technique was proposed to select the generalization parameter C and Gaussian kernel parameter γ. The focus is on the predictive accuracy and time response characteristics of the SVR model. Results show that ACO optimization algorithm can automatically obtain the optimal parameters, C and γ, of the SVR model with very high predictive accuracy. The predicted NOx emissions from the SVR model, by comparing with the BPNN model, were in good agreement with those measured, and were comparable to those estimated from the GRNN model. Time response of establishing the optimum SVR model was in scale of minutes, which is suitable for on-line and real-time modeling NOx emissions from coal-fired utility boilers. 相似文献
110.
在测算中部地区六省2000-2010年碳排放量的基础上,运用灰色关联分析方法对影响中部六省碳排放量的因素进行了分析.选取人口规模、人均GDP和能源强度作为影响碳排放的重要因素,对中部地区六个省份分别研究这3个因素与碳排放量之间的关联度,并根据研究结论提出了一些针对性的政策建议. 相似文献