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A Weighted Inner Product Estimator in the Geometric Algebra of Euclidean 3-Space for Source Localization Using an EM Vector-sensor

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Chinese Journal of Aeronautics 2012年第1期25卷 83-93页

作者： JIANG Jingfei zhang jianqiu Department of Electronic Engineering Fudan UniversityShanghai 200433China

In this paper, the source localization by utilizing the measurements of a single electromagnetic （EM） vector-sensor is investigated in the framework of the geometric algebra of Euclidean 3-space. In order to describe the orthogonality among the electric and magnetic measurements, two multivectors of the geometric algebra of Euclidean 3-space （G3） are used to model the outputs of a spatially collocated EM vector-sensor. Two estimators for the wave propagation vector estimation are then formulated by the inner product between a vector and a bivector in the G3. Since the information used by the two estimators is different, a weighted inner product estimator is then proposed to fuse the two estimators together in the sense of the minimum mean square error （MMSE）. Analytical results show that the statistical performances of the weighted inner product estimator are always better than its traditional cross product counterpart. The efficacy of the weighted inner product estimator and the correctness of the analytical predictions are demonstrated by simulation results.

关键词： cross product electromagnetic geometric algebra geometric algebra of Euclidean 3-space minimum mean square rule direction finding vector-sensor

The Marginal Rao-Blackwellized Particle Filter for Mixed Linear/Nonlinear State Space Models

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Chinese Journal of Aeronautics 2007年第4期20卷 346-352页

作者： Yin Jianjun zhang jianqiu Mike Klaas Department of Electronic Engineering Fudan University Shanghai 200433 China Department of Computer Science University of British Columbia Vancouver V6T1Z4 Canada

In this paper, the marginal Rao-Blackwellized particle filter （MRBPF）, which fuses the Rao-Blackwellized particle filter （RBPF） algorithm and the marginal particle filter （MPF） algorithm, is presented. The state space is divided into linear and non-linear parts, which can be estimated separately by the MPF and the optional Kalman filter. Through simulation in the terrain aided navigation （TAN） domain, it is demonstrated that, compared with the RBPF, the root mean square errors （RMSE） and the error variance of the nonlinear state estimations by the proposed MRBPF are respectively reduced by 29% and 96%, while the unique particle count is increased by 80%. It is also found that the MRBPF has better convergence properties, and analysis has shown that the existing RBPF is nothing more than a special case of the MRBPF.

关键词： signal processing marginal Rao-Blackwellized particle filter simulation mixed linear/nonlinear terrain aided navigation

A novel variable-lag probability hypothesis density smoother for multi-target tracking

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Chinese Journal of Aeronautics 2013年第4期26卷 1029-1037页

作者： Li Yue zhang jianqiu Yin Jianjun Department of Electronic Engineering Fudan University

It is understood that the forward-backward probability hypothesis density （PHD） smoothing algorithms proposed recently can significantly improve state estimation of targets. However, our analyses in this paper show that they cannot give a good cardinality （i.e., the number of targets） estimate. This is because backward smoothing ignores the effect of temporary track drop- ping caused by forward filtering and/or anomalous smoothing resulted from deaths of targets. To cope with such a problem, a novel PHD smoothing algorithm, called the variable-lag PHD smoother, in which a detection process used to identify whether the filtered cardinality varies within the smooth lag is added before backward smoothing, is developed here. The analytical results show that the proposed smoother can almost eliminate the influences of temporary track dropping and anomalous smoothing, while both the cardinality and the state estimations can significantly be improved. Simulation results on two multi-target tracking scenarios verify the effectiveness of the proposed smoother.

关键词： Dynamic models Probability hypothesis density (PHD) Random finite sets Smoother Target tracking

Greedy Matrix Completion with Fitting Error and Rank Iterative Minimization

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Chinese Journal of Electronics 2017年第4期26卷 814-819页

作者： WANG Youhua zhang Yiming zhang jianqiu HU Bo Key Laboratory of EMW Information (MoE) and the Department of Electronic Engineering Fudan University Science and Technology on Analog Integrated Circuit Laboratory Global Academic Fellow in Statistics New York University Abu Dhabi

A novel matrix completion algorithm which iteratively minimizes the fitting error and the matrix rank is presented. Unlike conventional matrix completion algorithms, which usually require some relaxation technique to cope with the low rank constraints, the proposed algorithm does not require any such techniques, thus making the selection of the parameter q of the matrix qnorm(0 < q ≤ 1) or the regularization parameter unnecessary. Simulation results of the random generated data and Jester joke data set verify our algorithm’s effectiveness and superiority over the reported algorithms in literature.

关键词： Low-rankness Matrix completion Spar sity Ma jorization minimization Singular value decompo sition

Development and Application of DCC Catalysts to Meet New Demands

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China Petroleum Processing & Petrochemical Technology 2013年第1期15卷 14-18页

作者： zhang jianqiu SINOPEC Research Institute of Petroleum Processing

The new generation of DCC catalysts, the DMMC/RMMC series catalysts developed by RIPP are introduced in this paper. The large molecule cracking ability is enhanced by increasing the portion of large pores; and the coke selectivity is improved by adjusting the acidity site density on the matrix surface, while the selective cracking reactions are increased. The sphericity of catalysts is improved by adopting new preparation method. The commercial application results have shown that applying DMMC/RMMC series catalysts with the mixed VGO, VGO plus AR, and hydrotreated VGO feed can increase the propylene yield by 2.43, 1.3 and 0.8 percentage points, respectively, as compared to the previous catalysts along with improvement in some products yields. The refining enterprises can make more profits after applying new series of DCC catalysts.

关键词： VGO resid catalytic cracking catalyst propylene light olefins

New normalized LMS adaptive filter with a variable regularization factor

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Journal of Systems Engineering and Electronics 2019年第2期30卷 259-269页

作者： LI Zhoufan LI Dan XU Xinlong zhang jianqiu School of Information Science and Technology Fudan University

A new normalized least mean square(NLMS) adaptive filter is first derived from a cost function, which incorporates the conventional one of the NLMS with a minimum-disturbance(MD)constraint. A variable regularization factor(RF) is then employed to control the contribution made by the MD constraint in the cost function. Analysis results show that the RF can be taken as a combination of the step size and regularization parameter in the conventional NLMS. This implies that these parameters can be jointly controlled by simply tuning the RF as the proposed algorithm does. It also demonstrates that the RF can accelerate the convergence rate of the proposed algorithm and its optimal value can be obtained by minimizing the squared noise-free posteriori error. A method for automatically determining the value of the RF is also presented, which is free of any prior knowledge of the noise. While simulation results verify the analytical ones, it is also illustrated that the performance of the proposed algorithm is superior to the state-of-art ones in both the steady-state misalignment and the convergence rate. A novel algorithm is proposed to solve some problems. Simulation results show the effectiveness of the proposed algorithm.

关键词： adaptive filtering normalized least mean square (NLMS) minimum-disturbance (MD) constraint variable regularization variable step-size NLMS

The incremental subgradient methods on distributed estimations in-network

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Science China(Information Sciences) 2014年第9期57卷 30-39页

作者： FENG Hui JIANG ZiDong HU Bo zhang jianqiu Department of Electronic Engineering Fudan University

A unified framework on distributed estimations in-network using incremental subgradient(IS)methods is *** IS methods meet the requirement of the asynchronously processing,which are efficient solvers developed recently focusing on separable non-differentiable convex optimization *** main contribution of this paper is to formalize distributed estimators as equivalent separable convex optimization problems,where general skills and several specific cases on signal estimations are *** and simulation results show that the IS framework can solve general nonlinear estimation problems in-network,and achieve comparable performances as the centralized estimators.

关键词： distributed signal processing signal processing in-network distributed estimation incremental subgradient optimization methods

^(15)N isotope fractionation in an aquatic food chain:Bellamya aeruginosa(Reeve) as an algal control agent

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Journal of Environmental Sciences 2010年第2期22卷 242-247页

作者： Shiqun Han Shaohua Yan Kaining Chen Zhenhua zhang Rengel Zed jianqiu zhang Wei Song Haiqin Liu Institute of Agricultural Resources and Environments Jiangsu Academy of Agricultural Sciences Nanjing 210014 China Nanjing Institute of Geography & Limnology Chinese Academy of Sciences Nanjing 210014 China School of Earth and Environment The University of Western Australia 35 Stirling Highway Crawley WA 6009 Australia

^ 15N isotope tracer techniques and ecological modeling were adopted to investigate the fractionation of nitrogen, its uptake and transformation in algae and snail （Bellamya aeruginosa Reeve）. Different algal species were found to differ in their uptake of nitrogen isotopes. Microcystis aeruginisa Ktitz. demonstrated the greatest ^15N accumulation capacity, with the natural variation in isotopic ratio （δ^15N） and the isotope fractionation factor （ε,‰） being the highest among the species investigated. The transformation and utilization of ^15N by snails differed depending on the specific algae consumed （highest for Chlorella pyrenoidosa Chick., lowest for M. aeruginisa）. When snails was seeded in the experimental pond, the algae population structure changed significantly, and total algal biomass as well as the concentration of all nitrogen species decreased, causing an increase in water transparency. A model, incorporating several chemical and biological parameters, was developed to predict algal biomass in an aquatic system when snails was present. The data collected during this investigation indicated that the gastropods such as snails could significantly impact biological community and water quality of small water bodies, suggesting a role for biological control of noxious algal blooms associated with eutrophication.

关键词： ^15N fractionation algal bloom Bellamya aeruginosa ecological modeling eutrophication

An optimal adaptive filtering algorithm with a polynomial prediction model

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Science China(Information Sciences) 2011年第1期54卷 153-162页

作者： TAN JiaJia & zhang jianqiu Department of Electronic Engineering,Fudan University,Shanghai 200433,China Department of Electronic Engineering Fudan University Shanghai China

A new approach to the optimal adaptive filtering is proposed in this *** this approach,a polynomial prediction model is used to describe the time-variant/invariant impulse response coeffcients of an identified *** the polynomial prediction model is viewed as the state equations of the identified impulse response coeffcients and the relationships between the inputs and outputs of the system are regarded as the measurements of the states,our adaptive filtering can be achieved in the framework of the Kalman filter. It is understood that Kalman filter is optimal in the sense of the MAP(maximum a posteriori),ML(most likelihood)and MMSE(minimum mean square error)under the linear and Gaussian white noise *** a result,our algorithm is also optimal in the statistical senses as Kalman filter does,provided that the impulse response coeffcients can be modeled by a *** only do the analytical results of the algorithm but also the simulation results show that our algorithm outperforms the traditional known algorithms.

关键词： adaptive filters polynomial prediction model impulse response coeffcients process equation Kalman filter optimal