Microseismic (MS) source location plays an important role in MS monitoring. This paper proposes a MS source location method based on particle swarm optimization (PSO) and multi-sensor arrays, where a free weight joint...Microseismic (MS) source location plays an important role in MS monitoring. This paper proposes a MS source location method based on particle swarm optimization (PSO) and multi-sensor arrays, where a free weight joints the P-wave first arrival data. This method adaptively adjusts the preference for “superior” arrays and leverages “inferior” arrays to escape local optima, thereby improving the location accuracy. The effectiveness and stability of this method were validated through synthetic tests, pencil-lead break (PLB) experiments, and mining engineering applications. Specifically, for synthetic tests with 1 μs Gaussian noise and 100 μs large noise in rock samples, the location error of the multi-sensor arrays jointed location method is only 0.30 cm, which improves location accuracy by 97.51% compared to that using a single sensor array. The average location error of PLB events on three surfaces of a rock sample is reduced by 48.95%, 26.40%, and 55.84%, respectively. For mine blast event tests, the average location error of the dual sensor arrays jointed method is 62.74 m, 54.32% and 14.29% lower than that using only sensor arrays 1 and 2, respectively. In summary, the proposed multi-sensor arrays jointed location method demonstrates good noise resistance, stability, and accuracy, providing a compelling new solution for MS location in relevant mining scenarios.展开更多
Jamming suppression is traditionally achieved through the use of spatial filters based on array signal processing theory.In order to achieve better jamming suppression performance,many studies have applied blind sourc...Jamming suppression is traditionally achieved through the use of spatial filters based on array signal processing theory.In order to achieve better jamming suppression performance,many studies have applied blind source separation(BSS)to jamming suppression.BSS can achieve the separation and extraction of the individual source signals from the mixed signal received by the array.This paper proposes a perspective to recognize BSS as spatial band-pass filters(SBPFs)for jamming suppression applications.The theoretical derivation indicates that the processing of mixed signals by BSS can be perceived as the application of a set of SBPFs that gate the source signals at various angles.Simulations are performed using radar jamming suppression as an example.The simulation results suggest that BSS and SBPFs produce approximately the same effects.Simulation results are consistent with theoretical derivation results.展开更多
Based on 310 horizontal-component digital seismograms recorded at 14 seismic stations in Shanxi Digital Seis-mograph Network, the inelastic attenuation coefficient in Shanxi region is studied. By the methods of Atkins...Based on 310 horizontal-component digital seismograms recorded at 14 seismic stations in Shanxi Digital Seis-mograph Network, the inelastic attenuation coefficient in Shanxi region is studied. By the methods of Atkinson and Moya, the site response of each station and several source parameters are obtained and the inversion results from both methods are compared and analyzed. The frequency-dependent inelastic attenuation coefficient Q is estimated as Q( f )=323.2 f 0.506. The site responses of 14 seismic stations do not show significant amplification, which is consistent with their basement on rock. We also found the dependence of corner frequency on seismic moment, seismic moment on stress drop, source radius on stress drop.展开更多
In the paper, source mechanisms of 33 small-moderate earthquakes occurred in Yunnan are determined by modeling of regional waveforms from Yunnan digital seismic network. The result shows that most earthquakes occurred...In the paper, source mechanisms of 33 small-moderate earthquakes occurred in Yunnan are determined by modeling of regional waveforms from Yunnan digital seismic network. The result shows that most earthquakes occurred within or near the Chuandian rhombic block have strike-slip mechanism. The orientations of maximum compressive stresses obtained from source mechanism are changed from NNW-SSN to NS in the areas from north to south of the block, and tensile stresses are mainly in ENE-WSW or NE-SE. In the eastern Tibetan Plateau, the orientations of maximum compressive stress radiate toward outside from the plateau, and the tensile stress orientations mostly parallel to arc structures. Near 28N the orientations of both maximum compressive stress and tensile stress changed greatly, and the boundary seems to correspond to the southwestern extended line of Longmenshan fault. Outside of the Chuandian rhombic block, the orientations of P and T axes are some different from those within the block. The comparison shows that the source mechanism of small-moderate events presented in the paper is consistence with that of moderate-strong earthquakes determined by Harvard University, which means the source mechanism of small-moderate events can be used to study the tectonic stress field in this region.展开更多
Blind source separation (BBS) technology was applied to vibration signal processing of gearbox for separating different fault vibration sources and enhancing fault information. An improved BSS algorithm based on parti...Blind source separation (BBS) technology was applied to vibration signal processing of gearbox for separating different fault vibration sources and enhancing fault information. An improved BSS algorithm based on particle swarm optimization (PSO) was proposed. It can change the traditional fault-enhancing thought based on de-noising. And it can also solve the practical difficult problem of fault location and low fault diagnosis rate in early stage. It was applied to the vibration signal of gearbox under three working states. The result proves that the BSS greatly enhances fault information and supplies technological method for diagnosis of weak fault.展开更多
The recovery of precious metals from the secondary resources by microwave technology has emerged in recent years. Microwave technology as a new method for the recovery of precious metals has shown significant advantag...The recovery of precious metals from the secondary resources by microwave technology has emerged in recent years. Microwave technology as a new method for the recovery of precious metals has shown significant advantages against the conventional recovery procedures. This paper presents a review of the advances in microwave technology applied to the recovery of precious metals from the secondary resources. Many different applications are considered, including microwave-assisted leaching, microwave augmented ashing and microwave pyrolysis. In general, microwave enhanced recovery of precious metals from secondary resources.展开更多
Blind separation of sparse sources （BSSS） is discussed. The BSSS method based on the conventional K-means clustering is very fast and is also easy to implement. However, the accuracy of this method is generally not ...Blind separation of sparse sources （BSSS） is discussed. The BSSS method based on the conventional K-means clustering is very fast and is also easy to implement. However, the accuracy of this method is generally not satisfactory. The contribution of the vector x（t） with different modules is theoretically proved to be unequal, and a weighted K-means clustering method is proposed on this grounds. The proposed algorithm is not only as fast as the conventional K-means clustering method, but can also achieve considerably accurate results, which is demonstrated by numerical experiments.展开更多
In order to achieve accurate recovery signals under the underdetermined circumstance in a comparatively short time,an algorithm based on plane pursuit(PP) is proposed. The proposed algorithm selects the atoms accordin...In order to achieve accurate recovery signals under the underdetermined circumstance in a comparatively short time,an algorithm based on plane pursuit(PP) is proposed. The proposed algorithm selects the atoms according to the correlation between received signals and hyper planes, which are composed by column vectors of the mixing matrix, and uses these atoms to recover source signals. Simulation results demonstrate that the PP algorithm has low complexity and higher accuracy as compared with basic pursuit(BP), orthogonal matching pursuit(OMP), and adaptive sparsity matching pursuit(ASMP) algorithms.展开更多
基金Project(SICGM2023301) supported by the State Key Laboratory of Strata Intelligent Control and Green Mining Co-founded by Shandong Province and the Ministry of Science and Technology,ChinaProject(SMDPC202202) supported by the Key Laboratory of Mining Disaster Prevention and Control,ChinaProject(U21A2030) supported by the National Natural Science Foundation of China。
文摘Microseismic (MS) source location plays an important role in MS monitoring. This paper proposes a MS source location method based on particle swarm optimization (PSO) and multi-sensor arrays, where a free weight joints the P-wave first arrival data. This method adaptively adjusts the preference for “superior” arrays and leverages “inferior” arrays to escape local optima, thereby improving the location accuracy. The effectiveness and stability of this method were validated through synthetic tests, pencil-lead break (PLB) experiments, and mining engineering applications. Specifically, for synthetic tests with 1 μs Gaussian noise and 100 μs large noise in rock samples, the location error of the multi-sensor arrays jointed location method is only 0.30 cm, which improves location accuracy by 97.51% compared to that using a single sensor array. The average location error of PLB events on three surfaces of a rock sample is reduced by 48.95%, 26.40%, and 55.84%, respectively. For mine blast event tests, the average location error of the dual sensor arrays jointed method is 62.74 m, 54.32% and 14.29% lower than that using only sensor arrays 1 and 2, respectively. In summary, the proposed multi-sensor arrays jointed location method demonstrates good noise resistance, stability, and accuracy, providing a compelling new solution for MS location in relevant mining scenarios.
基金supported by the National Natural Science Foundation of China(6237104662201048)the Natural Science Foundation of Chongqing,China(cstc2020jcyj-msxmX0260).
文摘Jamming suppression is traditionally achieved through the use of spatial filters based on array signal processing theory.In order to achieve better jamming suppression performance,many studies have applied blind source separation(BSS)to jamming suppression.BSS can achieve the separation and extraction of the individual source signals from the mixed signal received by the array.This paper proposes a perspective to recognize BSS as spatial band-pass filters(SBPFs)for jamming suppression applications.The theoretical derivation indicates that the processing of mixed signals by BSS can be perceived as the application of a set of SBPFs that gate the source signals at various angles.Simulations are performed using radar jamming suppression as an example.The simulation results suggest that BSS and SBPFs produce approximately the same effects.Simulation results are consistent with theoretical derivation results.
基金National Scientific Research Target Project of China (2001-BA601B01-01-05) during the tenth Five-year Plan.
文摘Based on 310 horizontal-component digital seismograms recorded at 14 seismic stations in Shanxi Digital Seis-mograph Network, the inelastic attenuation coefficient in Shanxi region is studied. By the methods of Atkinson and Moya, the site response of each station and several source parameters are obtained and the inversion results from both methods are compared and analyzed. The frequency-dependent inelastic attenuation coefficient Q is estimated as Q( f )=323.2 f 0.506. The site responses of 14 seismic stations do not show significant amplification, which is consistent with their basement on rock. We also found the dependence of corner frequency on seismic moment, seismic moment on stress drop, source radius on stress drop.
文摘In the paper, source mechanisms of 33 small-moderate earthquakes occurred in Yunnan are determined by modeling of regional waveforms from Yunnan digital seismic network. The result shows that most earthquakes occurred within or near the Chuandian rhombic block have strike-slip mechanism. The orientations of maximum compressive stresses obtained from source mechanism are changed from NNW-SSN to NS in the areas from north to south of the block, and tensile stresses are mainly in ENE-WSW or NE-SE. In the eastern Tibetan Plateau, the orientations of maximum compressive stress radiate toward outside from the plateau, and the tensile stress orientations mostly parallel to arc structures. Near 28N the orientations of both maximum compressive stress and tensile stress changed greatly, and the boundary seems to correspond to the southwestern extended line of Longmenshan fault. Outside of the Chuandian rhombic block, the orientations of P and T axes are some different from those within the block. The comparison shows that the source mechanism of small-moderate events presented in the paper is consistence with that of moderate-strong earthquakes determined by Harvard University, which means the source mechanism of small-moderate events can be used to study the tectonic stress field in this region.
基金Project(50875247) supported by the National Natural Science Foundation of ChinaProject(2007011070) supported by the Natural Science Foundation of Shanxi Province, China
文摘Blind source separation (BBS) technology was applied to vibration signal processing of gearbox for separating different fault vibration sources and enhancing fault information. An improved BSS algorithm based on particle swarm optimization (PSO) was proposed. It can change the traditional fault-enhancing thought based on de-noising. And it can also solve the practical difficult problem of fault location and low fault diagnosis rate in early stage. It was applied to the vibration signal of gearbox under three working states. The result proves that the BSS greatly enhances fault information and supplies technological method for diagnosis of weak fault.
文摘The recovery of precious metals from the secondary resources by microwave technology has emerged in recent years. Microwave technology as a new method for the recovery of precious metals has shown significant advantages against the conventional recovery procedures. This paper presents a review of the advances in microwave technology applied to the recovery of precious metals from the secondary resources. Many different applications are considered, including microwave-assisted leaching, microwave augmented ashing and microwave pyrolysis. In general, microwave enhanced recovery of precious metals from secondary resources.
基金the National Natural Science Foundation of China (60672061)
文摘Blind separation of sparse sources （BSSS） is discussed. The BSSS method based on the conventional K-means clustering is very fast and is also easy to implement. However, the accuracy of this method is generally not satisfactory. The contribution of the vector x（t） with different modules is theoretically proved to be unequal, and a weighted K-means clustering method is proposed on this grounds. The proposed algorithm is not only as fast as the conventional K-means clustering method, but can also achieve considerably accurate results, which is demonstrated by numerical experiments.
基金supported by the National Natural Science Foundation of China(61201134)the 111 Project(B08038)
文摘In order to achieve accurate recovery signals under the underdetermined circumstance in a comparatively short time,an algorithm based on plane pursuit(PP) is proposed. The proposed algorithm selects the atoms according to the correlation between received signals and hyper planes, which are composed by column vectors of the mixing matrix, and uses these atoms to recover source signals. Simulation results demonstrate that the PP algorithm has low complexity and higher accuracy as compared with basic pursuit(BP), orthogonal matching pursuit(OMP), and adaptive sparsity matching pursuit(ASMP) algorithms.
