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Two-Dimensional DOA Estimation Using One-Dimensional Search for Spherical Arrays

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Chinese Journal of Electronics 2019年第6期28卷 1259-1264页

作者： huang qinghua FENG Jiajun FANG Yong Key Laboratory of Specialty Fiber Optics and Optical Access Networks Shanghai University

A Reduced-dimensional spherical harmonics MUSIC(RD-SHMUSIC) is proposed to solve the problem of high computational complexity of Multiple signal classification(MUSIC) algorithm for Twodimensional(2-D) Direction of arrival(DOA) *** proposed algorithm first expresses the spherical harmonic steering vector as a linear weight of a uniform phase vectors. Via the Lagrange multiplier method, we can get a new search function to estimate elevations. At second step, the algorithm expresses the steering vector in another form, a linear weight of a vector which is constructed by associated Legendre functions. A search function to estimate azimuths can also be *** proposed method only needs One dimensional(1-D) angle search, which means it has a large reduction of computational complexity compared to the traditional Spherical harmonics MUSIC(SHMUSIC). The simulation results show that the accuracy of the proposed method is better than Two-stage decoupled approach(TSDA)algorithm, and has close performance to that of SHMUSIC.

关键词： Direction of arrival estimation Spherical arrays Reduced-dimensional spherical harmonics MUSIC Computational complexity

Near-Field Source Localization Using Spherical Microphone Arrays

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Chinese Journal of Electronics 2016年第1期25卷 159-166页

作者： huang qinghua ZHANG Guangfei LIU Kai Key Laboratory of Specialty Fiber Optics and Optical Access Networks Shanghai University

A new method is proposed for joint range and bearing(azimuth and elevation) estimation of multiple near-field acoustic sources using observations collected by a spherical microphone array. First, Spherical Fourier transform(SFT) is used to construct the array signal model in the spherical harmonics domain to decouple range and bearing information. Then the relation among the spherical harmonics of three adjacent degrees is exploited to build the recursive relationship of the signal subspace. Using Eigenvalue decomposition(EVD), bearings are estimated based on the eigenvalues and simultaneously the steering matrix can be represented by the signal ***, range is estimated using the energy ratios of the elements of the steering matrix in the spherical harmonics domain. The algorithm can avoid parameter pairing and multi-dimensional searching. It has lower computational complexity than that of the Multiple signal classification(MUSIC) method. The performance is evaluated by Monte-Carlo simulations and the estimation root meansquare errors are compared to the corresponding CramerRao bounds(CRBs) and those of MUSIC range estimates,which demonstrate the validity of the proposed algorithm.

关键词： Spherical microphone array Source localization Near-field Spherical Fourier transform(SFT) Spherical harmonics

Multi-dimensional EEF Criterion for Source Number Estimation

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Chinese Journal of Electronics 2014年第3期23卷 503-507页

作者： huang qinghua WANG Tong School of Communication and Information Engineering Shanghai University Institute of Computer and Information Shanghai Second Polytechnic University

When the number of snapshots is smaller than the dimension of the measured data, Exponential embedded family(EEF) rule fails to choose the correct model order. It is modified in this paper to enumerate sources in three-dimensional space unlimited by the number of snapshots. Then the modified EEF criterion is extended to RD version for the multi-dimensional data model based on Higher-order singular value decomposition(HOSVD). The R-D EEF criterion exploits the multi-dimensional structure of measurements and the eigenvalues of different mode sample covariance matrices jointly. It improves accuracy and robustness compared with the modified EEF criterion. Simulation results demonstrate the performance of the proposed enumerators.

关键词： Source enumeration Exponential embedded family Multi-dimensional structure Tensor model

DOA Estimation Using Block Variational Sparse Bayesian Learning

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Chinese Journal of Electronics 2017年第4期26卷 768-772页

作者： huang qinghua ZHANG Guangfei FANG Yong Key Laboratory of Specialty Fiber Optics and Optical Access Networks Shanghai University

In Direction-of-arrival(DOA) estimation,the real-valued sparse Bayesian algorithm degrades the estimation performance by decomposing the complex value into real and imaginary components and combining them independently. We directly use complex probability density functions to model the noise and complex-valued sparse direction weights. Based on the Multiple measurement vectors(MMV), block sparse structure for the direction weights is integrated into the variational Bayesian learning to provide accurate source direction estimates. The proposed algorithm can be used for arbitrary array geometries and does not need the prior information of the incident signal number. Simulation results demonstrate the better performance of the proposed method compared with the real-valued sparse Bayesian algorithm, the Orthogonal matching pursuit(OMP) and l1 norm based complexvalued methods.

关键词： Direction-of-arrival estimation Varia tional Bayesian learning Sparse recovery Multiple mea surement vectors Block sparse structure

Automatic ultrasound scanning system based on robotic arm

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Science China(Information Sciences) 2019年第5期62卷 35-37页

作者： qinghua huang Jiulong LAN Xuelong LI School of Mechanical Engineering and the Center for Optical Imagery Analysis and LearningNorthwestern Polytechnical University School of Electronic and Information Engineering South China University of Technology School of Computer Science and Center for OPTical IMagery Analysis and Learning (OPTIMAL) Northwestern Polytechnical University

Dear editor,As an indispensable diagnosis-aid technologies, ultrasound (US) examination gains more and more attention in recent years [1]. US could real-time display the 2D images of the region of interest in a way of... 详细信息

关键词： School USA Automatic ultrasound scanning system based on robotic arm

Preparation of Bi_(2-x)Sb_xTe_3 thermoelectric films by electrodeposition

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Journal of University of Science and Technology Beijing 2006年第3期13卷 277-280页

作者： qinghua huang Wei Wang Falong Jia Zhirong Zhang Department of Applied Chemistry School of Chemical Engineering and Technology Tianjin University Tianjin 300072 China

Bi2-xSbxTe3 thermoelectric films were electrochemically deposited from the solution containing Bi^3＋, HTeO2^＋and SbO^＋. ESEM （environmental scanning electron microscope） investigations indicated that the crystalline state of Bi2-xSbxTe3 films transformed from equiaxed crystal to dendritic crystal with the negative shift of deposition potential. XRD and EDS were used to characterize the structure and composition of the electrodeposited films. The Seebeck coefficient and the temperature dependence of the resistance of Bi2-xSbxTe3 films were measured. The results showed that the composition of the film electrodeposited at -0.5 V is Bi2-xSbxTe3 with the largest Seebeck coefficient of 213 μV·K^-1.

关键词： thermoelectric films bismuth antimony telluride compounds electrodeposition Seebeck coefficient morphology

Characteristics of earthquake clustering in and around Japan revealed by single-link cluster analysis

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Earthquake Science 2019年第5期32卷 221-228页

作者： Shuyuan Liu qinghua huang Department of Geophysics School of Earth and Space SciencesPeking UniversityBeijing 100871China

In this study,we apply the single-link cluster(SLC)method to analyze the characteristics of earth-quake clustering in *** the clustering algorithms,the SLC method is effpctive in characterizing earthquake clusters or isolated events at both global and local *** results indicate that link lengths for the whole investigated area in and around Japan follow negative exponential functi-onal or Gamma distribution functional ***,some difference is revealed among different areas,e.g.,link lengths in the area of the Japan Trench and the Kuril Trench are shorter than those in other areas;the densest spatial distribution of the SLC framework is also in the area of the Japan Trench and the Kuril *** close investigations indicate that the a and 1/θvalues estimated respectively from the exponential function and Gamma distribution may relate to spatial clustering,which is supported by the results of the distribution of link lengths and the spatial distribution of the SLC framework in the investigated areas.

关键词： earthquake clustering single-link cluster method Japan

A new numerical technique for simulating the coupled seismic and electromagnetic waves in layered porous media

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Earthquake Science 2010年第2期23卷 167-176页

作者： Hengxin Ren qinghua huang Xiaofei Chen School of Earth and Space Sciences University of Science and Technology of China Hefei 230026 China Department of Geophysics School of Earth and Space Sciences Peking University Beijing 100871 China

Chen＇s technique of computing synthetic seismograms, which decomposes every vector with a set of basis of orthogonality and completeness before applying the Luco-Apsel-Chen （LAC） generalized reflection and transmission coefficients method, is confirmed to be efficient in dealing with elastic waves in multi-layered media and accurate in any frequency range. In this article, we extend Chen＇s technique to the computation of coupled seismic and electromagnetic （EM） waves in layered porous media. Expanding the involved mechanical and electromagnetic fields by a set of scalar and vector wave-function basis, we obtain the fundamental equations which are subsequently solved by using a recently developed version of the LAC generalized reflection and transmission coefficients method. Our approach and corresponding program is validated by reciprocity tests. We also show a numerical example of a two-layer model with an explosion source. The P-to-EM conversion waves radiated from the interface may have potential application.

关键词： synthetic seismogram porous media electrokinetic effect generalized reflection and transmission coefficients

Recognition of Milankovitch Cycles in the Natural Gamma—Ray Logging of Upper Cretaceous Terrestrial Strata in the Songliao Basin

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Acta Geologica Sinica(English Edition) 2007年第6期81卷 996-1001页

作者： WU Huaichun ZHANG Shihong SUI Suwen huang qinghua State Key Laboratory of Geological Processes and Mineral Resources ＆ Key Laboratory of Lithosphere Tectonics and Lithoprobing Technology of Ministry of Education China University of Geosciences Beijing 100083 School of Marine Science China University of Geosciences Beijing 10008 Exploration and Development Research Institute of Daqing Oil Field Corporation Ltd. Daqing Heilongjiang 163712

Spectrogram analysis of seven natural gamma-ray logging of Member 1 of the Qingshankou Formation （K2qn^1） and Member 1 and 2 of the Nenjiang Formation （K2n^1-2） of Late Cretaceous age in the Songliao Basin reveals sedimentary cyclicities controlled by Milankovitch climate periodicities. The recognition of Milankovitch cycles allows estimation of an average accumulation rate of ～7.55- 8.62 cm/ka for the K2qn^1 sections, and ～6.69-10.16 cm/ka for the K2n^1-2 sections. Two marine transgression events occurred during the deposition of K2qn^1 and K2n^1-2 and their ages are at ～0.74- 1.10 Ma and ～2.38-4.84 Ma, respectively. Identification of Milankoviteh cycles from fine-grained deep lake sedimentary rocks in the Songliao Basin may provide great potential for high-resolution stratigraphic subdivisions and correlations.

关键词： Songliao Basin gamma-ray logging Milankovitch cycles marine transgression events