We find that a conserved mutation residue Glu to residue Asp (E303D), which both have the same polar and charged properties, makes Kit2.1 protein lose its function. To understand the mechanism, we identify three int...We find that a conserved mutation residue Glu to residue Asp (E303D), which both have the same polar and charged properties, makes Kit2.1 protein lose its function. To understand the mechanism, we identify three interactions which control the conformation change and maintain the function of the Kit2.1 protein by combining homology modeling and molecular dynamics with targeted molecular dynamics. We find that the E303D mutation weakens these interactions and results in the loss of the related function. Our data indicate that not only the amino residues but also the interactions determine the function of proteins.展开更多
Based on the characteristics of gradual change style seismic signal onset which has more high frequency signal components but less magnitude, this paper selects Gauss linear frequency modulation wavelet as base functi...Based on the characteristics of gradual change style seismic signal onset which has more high frequency signal components but less magnitude, this paper selects Gauss linear frequency modulation wavelet as base function to study the change characteristics of Gauss linear frequency modulation wavelet transform with difference wavelet and signal parameters, analyzes the error origin of seismic phases identification on the basis of Gauss linear frequency modulation wavelet transform, puts forward a kind of new method identifying gradual change style seismic phases with background noise which is called fixed scale wavelet transform ratio, and presents application examples about simulation digital signal and actual seismic phases recording onsets identification.展开更多
Fault detection and classification is a key challenge for the protection of High Voltage DC(HVDC)transmission lines.In this paper,the Teager-Kaiser Energy Operator(TKEO)algorithm associated with a decision tree-based ...Fault detection and classification is a key challenge for the protection of High Voltage DC(HVDC)transmission lines.In this paper,the Teager-Kaiser Energy Operator(TKEO)algorithm associated with a decision tree-based fault classi-fier is proposed to detect and classify various DC faults.The Change Identification Filter is applied to the average and differential current components,to detect the first instant of fault occurrence(above threshold)and register a Change Identified Point(CIP).Further,if a CIP is registered for a positive or negative line,only three samples of currents(i.e.,CIP and each side of CIP)are sent to the proposed TKEO algorithm,which produces their respective 8 indices through which the,fault can be detected along with its classification.The new approach enables quicker detection allowing utility grids to be restored as soon as possible.This novel approach also reduces computing complexity and the time required to identify faults with classification.The importance and accuracy of the proposed scheme are also thor-oughly tested and compared with other methods for various faults on HVDC transmission lines.展开更多
基金Supported by the National Natural Science Foundation of China under Grant Nos 11247010,11175055,11475053 and 11347017the Natural Science Foundation of Hebei Province under Grant Nos C2012202079 and C201400305
文摘We find that a conserved mutation residue Glu to residue Asp (E303D), which both have the same polar and charged properties, makes Kit2.1 protein lose its function. To understand the mechanism, we identify three interactions which control the conformation change and maintain the function of the Kit2.1 protein by combining homology modeling and molecular dynamics with targeted molecular dynamics. We find that the E303D mutation weakens these interactions and results in the loss of the related function. Our data indicate that not only the amino residues but also the interactions determine the function of proteins.
基金State Natural Science Foundation of China (40074007) Science and Technology Key Project during the Ten-Year Plan(2001BA601B02-03-06) and the Natural Science Foundation of Shandong Province (Y2000E08).
文摘Based on the characteristics of gradual change style seismic signal onset which has more high frequency signal components but less magnitude, this paper selects Gauss linear frequency modulation wavelet as base function to study the change characteristics of Gauss linear frequency modulation wavelet transform with difference wavelet and signal parameters, analyzes the error origin of seismic phases identification on the basis of Gauss linear frequency modulation wavelet transform, puts forward a kind of new method identifying gradual change style seismic phases with background noise which is called fixed scale wavelet transform ratio, and presents application examples about simulation digital signal and actual seismic phases recording onsets identification.
文摘Fault detection and classification is a key challenge for the protection of High Voltage DC(HVDC)transmission lines.In this paper,the Teager-Kaiser Energy Operator(TKEO)algorithm associated with a decision tree-based fault classi-fier is proposed to detect and classify various DC faults.The Change Identification Filter is applied to the average and differential current components,to detect the first instant of fault occurrence(above threshold)and register a Change Identified Point(CIP).Further,if a CIP is registered for a positive or negative line,only three samples of currents(i.e.,CIP and each side of CIP)are sent to the proposed TKEO algorithm,which produces their respective 8 indices through which the,fault can be detected along with its classification.The new approach enables quicker detection allowing utility grids to be restored as soon as possible.This novel approach also reduces computing complexity and the time required to identify faults with classification.The importance and accuracy of the proposed scheme are also thor-oughly tested and compared with other methods for various faults on HVDC transmission lines.