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Efficient matrix inversion based on VliW architecture

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Journal of Systems Engineering and Electronics 2014年第3期25卷 393-398页

作者： li Zhang fu li Guangming Shi School of Electronic Engineering Xidian University

Matrix inversion is a critical part in communication, signal processing and electromagnetic system. A flexible and scalable very long instruction word （VliW） processor with clustered architecture is proposed for matrix inversion. A global register file （RF） is used to connect al the clusters. Two nearby clusters share a local register file. The instruction sets are also designed for the VliW processor. Experimental results show that the proposed VliW architecture takes only 45 latency to invert a 4 × 4 matrix when running at 150 MHz. The proposed design is roughly five times faster than the DSP solution in processing speed.

关键词： matrix inversion very long instruction word (VliW),latency register file (RF) cluster.

Real-time total system error estimation: Modeling and application in required navigation performance

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Chinese Journal of Aeronautics 2014年第6期27卷 1544-1553页

作者： fu li Zhang Jun li Rui National Key Laboratory of CNS/ATM School of Electronic and Information Engineering Beihang University

In required navigation performance（RNP）, total system error（TSE） is estimated to provide a timely warning in the presence of an excessive error. In this paper, by analyzing the underlying formation mechanism, the TSE estimation is modeled as the estimation fusion of a fixed bias and a Gaussian random variable. To address the challenge of high computational load induced by the accurate numerical method, two efficient methods are proposed for real-time application, which are called the circle tangent ellipse method（CTEM） and the line tangent ellipse method（LTEM）,respectively. Compared with the accurate numerical method and the traditional scalar quantity summation method（SQSM）, the computational load and accuracy of these four methods are extensively analyzed. The theoretical and experimental results both show that the computing time of the LTEM is approximately equal to that of the SQSM, while it is only about 1/30 and 1/6 of that of the numerical method and the CTEM. Moreover, the estimation result of the LTEM is parallel with that of the numerical method, but is more accurate than those of the SQSM and the CTEM. It is illustrated that the LTEM is quite appropriate for real-time TSE estimation in RNP application.

关键词： Aviation Estimation Navigation Required navigation performance Total system error

Optimization-based particle filter for state and parameter estimation

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Journal of Systems Engineering and Electronics 2009年第3期20卷 479-484页

作者： li fu Qi Fei Shi Guangming Zhang li School of Electronic Engineering Xidian Univ. Xi'an 710071 P. R. China

In recent years, the theory of particle filter has been developed and widely used for state and parameter estimation in nonlinear/non-Gaussian systems. Choosing good importance density is a critical issue in particle filter design. In order to improve the approximation of posterior distribution, this paper provides an optimization-based algorithm （the steepest descent method） to generate the proposal distribution and then sample particles from the distribution. This algorithm is applied in 1-D case, and the simulation results show that the proposed particle filter performs better than the extended Kalman filter （EKF）, the standard particle filter （PF）, the extended Kalman particle filter （PF-EKF） and the unscented particle filter （UPF） both in efficiency and in estimation precision.

关键词： importance density particle filter extend Kalman filter

Bandwidth adaption for kernel particle filter

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Journal of Systems Engineering and Electronics 2011年第2期22卷 340-346页

作者： fu li Guangming Shi Fei Qi li Zhang School of Electronic Engineering Xidian University Xi'an 710071 P. R. China

A novel particle filter bandwidth adaption for kernel particle filter （BAKPF） is proposed. Selection of the kernel bandwidth is a critical issue in kernel density estimation （KDE）. The plug-in method is adopted to get the global fixed bandwidth by optimizing the asymptotic mean integrated squared error （AMISE） firstly. Then, particle-driven bandwidth selection is invoked in the KDE. To get a more effective allocation of the particles, the KDE with adap- tive bandwidth in the BAKPF is used to approximate the posterior probability density function （PDF） by moving particles toward the posterior. A closed-form expression of the true distribution is given. The simulation results show that the proposed BAKPF performs better than the standard particle filter （PF）, unscented particle filter （UPF） and the kernel particle filter （KPF） both in efficiency and estimation precision.

关键词： kernel density estimation adaptive bandwidth kernel,particle filter.

ANALYSIS OF FIRST TRANSIENT PRESSURE OSCILLATION FOR LEAKDETECTION IN A SINGLE PIPEliNE

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Journal of Hydrodynamics 2012年第3期24卷 363-370页

作者： YANG Kai-lin li fu-tian WANG Tao fu hui State Key Laboratory of Simulation and Regulation of Water Cycle in River Basin China Institute of WaterResources and Hydropower Research Beijing 100038 China

The leak detection is of great importance in the reliable operation and management of a pipeline system. Recently, attention is shifted to the use of the time domain or frequency domain methods based on the transient analysis. These methods sometimes require accurate pressure signals obtained during the transient period or by creating ideal conditions in testing. This paper proposes a method that does not require transient simulations over the whole or an extended period of time, but uses the first transient pressure oscillation to detect leaks. The method considers the propagation of the pressure oscillation wave created from a fast valve closure and the reflected damp wave from the leak. A leak in the pipe gives rise to reflected waves which in turn create discontinuities in the observed signal at the measurement section. The timing of the reflected damp wave and the magnitude represent the location and the size of the leak, respectively. An analytical expression is derived based on the Method Of Characteristic （MOC） for the relationship between the leakage and the reflected magnitude. The leak detection procedure based on the method is also given. Then the reliability of the method is tested on numerically simulated pressure signals and experimental pressure signals with calibrated leak parameters, and the results indicate a successful application and the promising features of the method.

关键词： leak detection hydraulic transient pressure oscillation pipeline

STABIliTY ANALYSIS OF RUNGE-KUTTA METHODS FOR NONliNEAR SYSTEMS OF PANTOGRAPH EQUATIONS

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Journal of Computational Mathematics 2005年第4期23卷 351-356页

作者： Yue-xin Yu Shou-fu li Department of Mathematics Xiangtan University Xiangtan 411105 China

This paper is concerned with numerical stability of nonlinear systems of pantograph equations. Numerical methods based on （k, l）-algebraically stable Runge-Kutta methods are suggested. Global and asymptotic stabilit... 详细信息

关键词： Nonlinear pantograph equations Runge-Kutta methods Numerical stability Asymptotic stability

Distribution of gas hydrate in fractured reservoirs:Insights from anisotropic seismic measurements

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Science China Earth Sciences 2021年第5期64卷 744-752页

作者： Shengbiao liU Tongcheng HAN li-Yun fu School of Geosciences China University of Petroleum(East China)Qingdao 266580China Laboratory for Marine Mineral Resources Pilot National Laboratory for Marine Science and Technology(Qingdao)Qingdao 266071China

Seismic properties of hydrate-bearing reservoirs that are affected significantly by the hydrate distribution are key for quantitative assessment of the *** knowledge of hydrate distribution in fractured reservoirs remains poorly *** obtain such knowledge,we measured and analyzed five anisotropic velocities needed to fully characterize the seismic anisotropy in an artificial sandstone with aligned fractures during hydrate formation associated with varying *** showed that while the formation of hydrate improved the velocities,the improvement was more significant for hydrate saturation above 10%.We also showed that the increasing trends varied among the anisotropic velocities when hydrate saturation was above 10%.Specifically,the compressional wave velocity travelling vertical to the bedding plane and the shear wave velocity with polarization perpendicular to the bedding plane increased more rapidly than the other compressional and shear wave velocities,*** of the anisotropic seismic results suggested that the hydrate tends to bind to the grains in the fractures at low hydrate saturation,and becomes to bridge the fracture surfaces when the hydrate saturation exceeds 10%.The results have provided new insights into the hydrate distribution and its resulting anisotropic seismic properties in fractured *** will pave the way for the successful assessment of hydrate in fractured reservoirs.

关键词： Fractured hydrate reservoirs Hydrate distribution Seismic anisotropy Anisotropic velocities measurements

Metabolic pathway modulation by olanzapine:Multitarget approach for treating violent aggression in patients with schizophrenia

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World Journal of Psychiatry 2025年第1期15卷 37-53页

作者： Yan-Ning Song Shuang Xia Zhi Sun Yong-Chao Chen Lu Jiao Wen-Hua Wan Hong-Wei Zhang Xiao Guo Hua Guo Shou-Feng Jia Xiao-Xin li Shi-Xian Cao li-Bin fu Meng-Meng liu Tian Zhou Lv-Feng Zhang Qing-Quan Jia Department of Pharmacy The Affiliated Encephalopathy Hospital of Zhengzhou University(Zhumadian Second People's Hospital)Zhumadian 463000Henan ProvinceChina Department of Pharmacy The First Affiliated Hospital of Zhengzhou UniversityZhengzhou 450052Henan ProvinceChina Department of Pharmacy Zhumadian First People's HospitalZhumadian 463000Henan ProvinceChina Scientific Education Section The Affiliated Encephalopathy Hospital of Zhengzhou University(Zhumadian Second People's Hospital)Zhumadian 463000Henan ProvinceChina Department of Psychiatry The Affiliated Encephalopathy Hospital of Zhengzhou University(Zhumadian Second People's Hospital)Zhumadian 463000Henan ProvinceChina Clinical Laboratory The Affiliated Encephalopathy Hospital of Zhengzhou University(Zhumadian Second People's Hospital)Zhumadian 463000Henan ProvinceChina Publicity Division The Affiliated Encephalopathy Hospital of Zhengzhou University(Zhumadian Second People's Hospital)Zhumadian 463000Henan ProvinceChina

BACKGROUND The use of network pharmacology and blood metabolomics to study the patho-genesis of violent aggression in patients with schizophrenia and the related drug mechanisms of action provides new directions for reducing the risk of violent aggression and optimizing treatment *** To explore the metabolic regulatory mechanism of olanzapine in treating patients with schizophrenia with a moderate to high risk of violent *** Metabolomic technology was used to screen differentially abundant metabolites in patients with schizophrenia with a moderate to high risk of violent aggression before and after olanzapine treatment,and the related metabolic pathways were *** pharmacology was used to establish protein-protein interaction networks of the core targets of *** Ontology functional analysis and Kyoto Encyclopedia of Genes and Genomes pathway enrichment analysis were subsequently *** Compared with the healthy group,the patients with schizophrenia group presented significant changes in the levels of 24 metabolites related to the disruption of 9 metabolic pathways,among which the key pathways were the alanine,aspartate and glutamate metabolism and arginine biosynthesis *** treatment with olanzapine,the levels of 10 differentially abundant metabolites were significantly reversed in patients with *** effectively regulated six metabolic pathways,among which the key pathways were alanine,aspartate and glutamate metabolism and arginine biosynthesis *** core targets of olanzapine were involved in several key *** The metabolic pathways of alanine,aspartate,and glutamate metabolism and arginine biosynthesis are the key pathways involved in olanzapine treatment for aggressive schizophrenia.

关键词： Schizophrenia Violent aggression Olanzapine Metabolomics Network pharmacology

Evolution of inclusions in a pipeline steel during continuous casting and hot rolling process

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Journal of Iron and Steel Research International 2022年第1期29卷 175-185页

作者： Yi Wang Wei-fu li Wen Yang School of Metallurgical and Ecological Engineering University of Science and Technology BeijingBeijing 100083China

Industrial trials were performed to study the evolution of inclusions in a pipeline steel during the continuous casting and hot rolling *** main composition of inclusions changed from Al_(2)O_(3)-CaO in the liquid steel to Al_(2)O_(3)-CaO-CaS in the slab,and then to Al_(2)O_(3)-CaS in the rolled *** area fractions of inclusions increased from 47.0×10^(-6) to 76.7×10^(-6),and to 144.3×10^(-6).It was explained by thermodynamic calculations that the thermodynamic equilibrium between inclusions and the steel varied with the *** contents of Al,Ca,Mg,S,and O in the steel decreased during the solidification and cooling *** to the difference in the cooling rate,the transformation ratio of CaS increased from 61% at the slab surface to 95% in the slab *** was also affected by the size of inclusions as smaller inclusions provided better kinetic *** diameters of inclusions for the composition transformation were *** the hot rolling process,the average aspect ratio of inclusions increased from 1.4 in the slab to 2.8 in the rolled *** the hot rolling process,a part of inclusions was crushed into small particles of CaS phase and Al_(2)O_(3)-CaO-MgO cores,leading to a decrease in CaS content of inclusions.

关键词： Inclusion Pipeline steel Continuous casting Hot rolling Deformation