To make the modulation classification system more suitable for signals in a wide range of signal to noise rate （SNR）, a feature extraction method based on signal wavelet packet transform modulus maxima matrix （WPT...To make the modulation classification system more suitable for signals in a wide range of signal to noise rate （SNR）, a feature extraction method based on signal wavelet packet transform modulus maxima matrix （WPTMMM） and a novel support vector machine fuzzy network （SVMFN） classifier is presented. The WPTMMM feature extraction method has less computational complexity, more stability, and has the preferable advantage of robust with the time parallel moving and white noise. Further, the SVMFN uses a new definition of fuzzy density that incorporates accuracy and uncertainty of the classifiers to improve recognition reliability to classify nine digital modulation types （i.e. 2ASK, 2FSK, 2PSK, 4ASK, 4FSK, 4PSK, 16QAM, MSK, and OQPSK）. Computer simulation shows that the proposed scheme has the advantages of high accuracy and reliability （success rates are over 98% when SNR is not lower than 0dB）, and it adapts to engineering applications.展开更多
In this paper a novel coding method based on fuzzy vector quantization for noised image with Gaussian white-noise pollution is presented. By restraining the high frequency subbands of wavelet image the noise is signif...In this paper a novel coding method based on fuzzy vector quantization for noised image with Gaussian white-noise pollution is presented. By restraining the high frequency subbands of wavelet image the noise is significantly removed and coded with fuzzy vector quantization. The experimental result shows that the method can not only achieve high compression ratio but also remove noise dramatically.展开更多
在“双碳”背景下,含混合储能系统(hybrid energy storage system,HESS)的风电场对系统配置优化能力的要求不断提高。为提升系统配置优化协同性,实现风电波动平抑,综合考虑经济性、平抑效果和使用寿命,提出了一种基于模糊控制的并网风...在“双碳”背景下,含混合储能系统(hybrid energy storage system,HESS)的风电场对系统配置优化能力的要求不断提高。为提升系统配置优化协同性,实现风电波动平抑,综合考虑经济性、平抑效果和使用寿命,提出了一种基于模糊控制的并网风储一体化系统多目标优化配置方法。首先,为了使储能功率与风电场的性能特征相匹配,应用快速傅里叶变换(fast Fourier transform,FFT)作为分频方法,实现了自适应小波包平滑策略下的HESS功率分配。然后,基于经济性和平抑效果建立多目标优化模型,确定了最优的HESS配置方案。最后,设计优化储能使用寿命的模糊控制策略,改善了高功率存储(high power storage,HPS)的充放电水平,有效优化了HPS的荷电状态(state of charge,SOC)。展开更多
电网发生故障时,故障信号主要包括开关量和电气量。开关量是继电保护的动作信息,目前的故障诊断方法主要基于开关量;电气量是各种故障暂态信息,它蕴含了故障的特征信息,但很少应用于电网故障诊断。提出一种基于改进D-S证据理论的多数据...电网发生故障时,故障信号主要包括开关量和电气量。开关量是继电保护的动作信息,目前的故障诊断方法主要基于开关量;电气量是各种故障暂态信息,它蕴含了故障的特征信息,但很少应用于电网故障诊断。提出一种基于改进D-S证据理论的多数据源信息融合故障诊断方法(information fusion of multi-data resources in fault diagnosis based on improved D-S theory,IMFD),首先对故障信息进行特征提取,通过模糊Petri网将开关量转化为元件的模糊故障度;利用小波变换分析电气量,得到元件的小波故障表征。然后基于改进的D-S证据理论进行信息融合,最后采用C-均值法决策故障元件。仿真计算表明,该方法将电气量和开关量进行信息融合,得到精确的故障诊断结果,在电网故障诊断中有良好的应用前景。展开更多
文摘To make the modulation classification system more suitable for signals in a wide range of signal to noise rate （SNR）, a feature extraction method based on signal wavelet packet transform modulus maxima matrix （WPTMMM） and a novel support vector machine fuzzy network （SVMFN） classifier is presented. The WPTMMM feature extraction method has less computational complexity, more stability, and has the preferable advantage of robust with the time parallel moving and white noise. Further, the SVMFN uses a new definition of fuzzy density that incorporates accuracy and uncertainty of the classifiers to improve recognition reliability to classify nine digital modulation types （i.e. 2ASK, 2FSK, 2PSK, 4ASK, 4FSK, 4PSK, 16QAM, MSK, and OQPSK）. Computer simulation shows that the proposed scheme has the advantages of high accuracy and reliability （success rates are over 98% when SNR is not lower than 0dB）, and it adapts to engineering applications.
文摘In this paper a novel coding method based on fuzzy vector quantization for noised image with Gaussian white-noise pollution is presented. By restraining the high frequency subbands of wavelet image the noise is significantly removed and coded with fuzzy vector quantization. The experimental result shows that the method can not only achieve high compression ratio but also remove noise dramatically.
文摘在“双碳”背景下,含混合储能系统(hybrid energy storage system,HESS)的风电场对系统配置优化能力的要求不断提高。为提升系统配置优化协同性,实现风电波动平抑,综合考虑经济性、平抑效果和使用寿命,提出了一种基于模糊控制的并网风储一体化系统多目标优化配置方法。首先,为了使储能功率与风电场的性能特征相匹配,应用快速傅里叶变换(fast Fourier transform,FFT)作为分频方法,实现了自适应小波包平滑策略下的HESS功率分配。然后,基于经济性和平抑效果建立多目标优化模型,确定了最优的HESS配置方案。最后,设计优化储能使用寿命的模糊控制策略,改善了高功率存储(high power storage,HPS)的充放电水平,有效优化了HPS的荷电状态(state of charge,SOC)。
文摘电网发生故障时,故障信号主要包括开关量和电气量。开关量是继电保护的动作信息,目前的故障诊断方法主要基于开关量;电气量是各种故障暂态信息,它蕴含了故障的特征信息,但很少应用于电网故障诊断。提出一种基于改进D-S证据理论的多数据源信息融合故障诊断方法(information fusion of multi-data resources in fault diagnosis based on improved D-S theory,IMFD),首先对故障信息进行特征提取,通过模糊Petri网将开关量转化为元件的模糊故障度;利用小波变换分析电气量,得到元件的小波故障表征。然后基于改进的D-S证据理论进行信息融合,最后采用C-均值法决策故障元件。仿真计算表明,该方法将电气量和开关量进行信息融合,得到精确的故障诊断结果,在电网故障诊断中有良好的应用前景。
