This paper presents an artificial neural network, ANN, based approach for estimating short-term wholesale electricity prices using past price and demand data. The objective is to utilize the piecewise continuous na-tu...This paper presents an artificial neural network, ANN, based approach for estimating short-term wholesale electricity prices using past price and demand data. The objective is to utilize the piecewise continuous na-ture of electricity prices on the time domain by clustering the input data into time ranges where the variation trends are maintained. Due to the imprecise nature of cluster boundaries a fuzzy inference technique is em-ployed to handle data that lies at the intersections. As a necessary step in forecasting prices the anticipated electricity demand at the target time is estimated first using a separate ANN. The Australian New-South Wales electricity market data was used to test the system. The developed system shows considerable im-provement in performance compared with approaches that regard price data as a single continuous time se-ries, achieving MAPE of less than 2% for hours with steady prices and 8% for the clusters covering time pe-riods with price spikes.展开更多
Ontology is defined as an explicit specification of a conceptualization. In this paper, an extended ontology model was constructed using description logics, which is a 5-tuples including term set, individual set, term...Ontology is defined as an explicit specification of a conceptualization. In this paper, an extended ontology model was constructed using description logics, which is a 5-tuples including term set, individual set, term definition set, instantiation assertion set and term restriction set. Based on the extended model, the issue on ontology checking was studied with the conclusion that the four kinds of term checking, including term satisfiability checking, term subsumption checking, term equivalence checking and term disjointness checking, can be reduced to the satisfiability checking, and satisfiability checking can be transformed into instantiation consistence checking.展开更多
This paper introduces the base-X notation and discusses the conversion between numbers of different bases. It also introduces the tri-value logic that is associated with the base-3 system.
危险驾驶行为分析与预测是智能交通领域中的研究热点,但现有的驾驶行为分析模型要素单一、环境适应性不足,不能客观评估危险驾驶风险程度。为了解决上述问题,提出一种面向车联网(Internet of Vehicles,IoV)的自适应危险驾驶行为分析与...危险驾驶行为分析与预测是智能交通领域中的研究热点,但现有的驾驶行为分析模型要素单一、环境适应性不足,不能客观评估危险驾驶风险程度。为了解决上述问题,提出一种面向车联网(Internet of Vehicles,IoV)的自适应危险驾驶行为分析与预测框架。对驾驶行为数据进行深度分析,总结危险驾驶的影响因素;提出一种新型基于模糊逻辑的危险驾驶风险评估算法,从宏观角度评估驾驶员当前危险驾驶的风险等级;提出一种基于DB-LSTM(Driving Behavior based Long-Short Term Memory)的危险驾驶风险预测算法,用于预测驾驶员下一阶段的危险驾驶程度;在DDD17真实IoV数据集上进行大量对比试验。实验结果表明,提出模型的性能优于其他主流方法,具有良好的准确性和可用性。展开更多
文摘This paper presents an artificial neural network, ANN, based approach for estimating short-term wholesale electricity prices using past price and demand data. The objective is to utilize the piecewise continuous na-ture of electricity prices on the time domain by clustering the input data into time ranges where the variation trends are maintained. Due to the imprecise nature of cluster boundaries a fuzzy inference technique is em-ployed to handle data that lies at the intersections. As a necessary step in forecasting prices the anticipated electricity demand at the target time is estimated first using a separate ANN. The Australian New-South Wales electricity market data was used to test the system. The developed system shows considerable im-provement in performance compared with approaches that regard price data as a single continuous time se-ries, achieving MAPE of less than 2% for hours with steady prices and 8% for the clusters covering time pe-riods with price spikes.
基金National Natural Science Foundation ofChina(No.70 2 710 3 8)
文摘Ontology is defined as an explicit specification of a conceptualization. In this paper, an extended ontology model was constructed using description logics, which is a 5-tuples including term set, individual set, term definition set, instantiation assertion set and term restriction set. Based on the extended model, the issue on ontology checking was studied with the conclusion that the four kinds of term checking, including term satisfiability checking, term subsumption checking, term equivalence checking and term disjointness checking, can be reduced to the satisfiability checking, and satisfiability checking can be transformed into instantiation consistence checking.
文摘This paper introduces the base-X notation and discusses the conversion between numbers of different bases. It also introduces the tri-value logic that is associated with the base-3 system.
文摘危险驾驶行为分析与预测是智能交通领域中的研究热点,但现有的驾驶行为分析模型要素单一、环境适应性不足,不能客观评估危险驾驶风险程度。为了解决上述问题,提出一种面向车联网(Internet of Vehicles,IoV)的自适应危险驾驶行为分析与预测框架。对驾驶行为数据进行深度分析,总结危险驾驶的影响因素;提出一种新型基于模糊逻辑的危险驾驶风险评估算法,从宏观角度评估驾驶员当前危险驾驶的风险等级;提出一种基于DB-LSTM(Driving Behavior based Long-Short Term Memory)的危险驾驶风险预测算法,用于预测驾驶员下一阶段的危险驾驶程度;在DDD17真实IoV数据集上进行大量对比试验。实验结果表明,提出模型的性能优于其他主流方法,具有良好的准确性和可用性。
