As the mining depth of coal resources increases,resulting in frequent mine earthquakes during mining.In this study,the rolling window ratio method is firstly chosen as the seismic phase recognition method to read the ...As the mining depth of coal resources increases,resulting in frequent mine earthquakes during mining.In this study,the rolling window ratio method is firstly chosen as the seismic phase recognition method to read the mine earthquake data received by the microseismic sensor.Secondly,the improved genetic algorithm is used as the optimization algorithm of the objective function to build the algorithmic framework of accurate inverse localization of mine earthquake.Finally,the accuracy of this algorithm for seismic source localization is validated using actual engineering cases.Results show that the first arrival time extraction by the rolling window ratio method has the advantages of high accuracy and fast algorithm operation speed.The Fast Fourier Transform-Butterworth joint noise reduction method has a good noise reduction effect,which successfully suppressing noise outside the mine earthquake signal and effectively improving the issue of excessive noise in the mine earthquake signal.Compared to microseismic monitoring data,the localization error for mine earthquakes remains within 5%.展开更多
为了有效增强指纹,提出了一种改进的基于曲率的自适应非接触式指纹图像增强算法.首先,对局部平稳的指纹图像信号进行STFT(short time Fourier transform)分析,确定纹理模式频谱所在的主要区域,对频谱进行根滤波和形态学平滑后,用均值...为了有效增强指纹,提出了一种改进的基于曲率的自适应非接触式指纹图像增强算法.首先,对局部平稳的指纹图像信号进行STFT(short time Fourier transform)分析,确定纹理模式频谱所在的主要区域,对频谱进行根滤波和形态学平滑后,用均值-门限法提取STFT主频谱成分;然后,提出一种角度和径向估计方法,计算指纹图像在频域的方向图和频率图;最后,根据指纹的曲率,构造相应的巴特沃斯陷波带通滤波器和高斯带通滤波器分别对低曲率区域和高曲率区域进行滤波,有效地滤除奇异点区域和非奇异点区域的噪声模式频率并保留纹线模式的主频率.将提出算法和同类算法进行主客观的实验比较,实验结果表明:提出的算法优于现有算法,能有效滤除非接触式指纹的噪声、增强脊线和谷线之间对比度,同时修复并增强正确的脊线结构.展开更多
基金supported by the Shandong Energy Group(No.SNKJ2022A01-R26).
文摘As the mining depth of coal resources increases,resulting in frequent mine earthquakes during mining.In this study,the rolling window ratio method is firstly chosen as the seismic phase recognition method to read the mine earthquake data received by the microseismic sensor.Secondly,the improved genetic algorithm is used as the optimization algorithm of the objective function to build the algorithmic framework of accurate inverse localization of mine earthquake.Finally,the accuracy of this algorithm for seismic source localization is validated using actual engineering cases.Results show that the first arrival time extraction by the rolling window ratio method has the advantages of high accuracy and fast algorithm operation speed.The Fast Fourier Transform-Butterworth joint noise reduction method has a good noise reduction effect,which successfully suppressing noise outside the mine earthquake signal and effectively improving the issue of excessive noise in the mine earthquake signal.Compared to microseismic monitoring data,the localization error for mine earthquakes remains within 5%.
文摘为了有效增强指纹,提出了一种改进的基于曲率的自适应非接触式指纹图像增强算法.首先,对局部平稳的指纹图像信号进行STFT(short time Fourier transform)分析,确定纹理模式频谱所在的主要区域,对频谱进行根滤波和形态学平滑后,用均值-门限法提取STFT主频谱成分;然后,提出一种角度和径向估计方法,计算指纹图像在频域的方向图和频率图;最后,根据指纹的曲率,构造相应的巴特沃斯陷波带通滤波器和高斯带通滤波器分别对低曲率区域和高曲率区域进行滤波,有效地滤除奇异点区域和非奇异点区域的噪声模式频率并保留纹线模式的主频率.将提出算法和同类算法进行主客观的实验比较,实验结果表明:提出的算法优于现有算法,能有效滤除非接触式指纹的噪声、增强脊线和谷线之间对比度,同时修复并增强正确的脊线结构.
基金The project is partially supported by a grant from Beijing Educational Committee(No.KM200410005013)NSFC(No.10671008)Beijing Program of"Ren Cai Qiang Jiao".