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Semiparametric Two-Component Mixture Models When One Component Is Defined Through linear constraints

IEEE TRANSACTIONS ON INFORMATION THEORY 2018年第2期64卷 795-830页

作者： Al Mohamad, Diaa Boumahdaf, Assia Leiden Univ Med Ctr Dept Bioinformat & Med Stat NL-2333 Leiden Netherlands Fritlink F-75018 Paris France

We propose a structure of a semiparametric two-component mixture model when one component is parametric and the other is defined through linear constraints on either its distribution function or its quantile measure. Estimation of a two-component mixture model with an unknown component is very difficult when no particular assumption is made on the structure of the unknown component. A symmetry assumption was used in the literature to simplify the estimation. Such method has the advantage of producing consistent and asymptotically normal estimators, and identifiability of the semiparametric mixture model becomes tractable. Still, existing methods, which estimate a semiparametric mixture model have their limits when the parametric component has unknown parameters or the proportion of the parametric part is either very high or very low. We propose in this paper a method to incorporate a prior linear information about the unknown component in order to better estimate the model when existing estimation methods fail. This linear information is either translated by linear constraints, such as moment-type constraints or L-moments constraints (linear constraints over the quantile). The new method is based on phi-divergences and has a non classical form since the minimization is carried over both arguments of the divergence. The resulting estimators are proved to be consistent and asymptotically normal under standard assumptions. We show that using the Pearson's chi(2) divergence our algorithm has a linear complexity when the constraints are moment-type. Simulations on univariate and multivariate mixtures demonstrate the viability and the interest of our novel approach.

关键词： Fenchel duality L-moments identifiability linear constraint semiparametric mixture model signed measures phi-divergence

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Improved positioning algorithm based on linear constraints on scatterers

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EURASIP JOURNAL ON WIRELESS COMMUNICATIONS AND NETWORKING 2013年第1期2013卷 1-10页

作者： Zhou, Fei Fan, Xin-yue Chen, Ting-Ying Chongqing Univ Posts & Telecommun CQUPT Chongqing Key Lab Mobile Commun Technol Chongqing Peoples R China

Non-line-of-sight (NLOS) error is a bottleneck problem influencing positioning accuracy. However, a large number of scatterers distribute randomly in the surrounding of the mobile station (MS) in the dense multipath environment, such as urban. In most cases, there is no obstacle between scatterer and MS. So, the geographic information of scatterers around MS can be used to restraint NLOS errors and improve the positioning accuracy. If scatterer can be regarded as the virtual base station (BS), the precondition of the positioning algorithm is easier to satisfy than the traditional positioning algorithm, such as circle positioning algorithm. The algorithm proposed in this article selects suitable scatterers with linear constraints by analyzing the Doppler frequency shift of received signals which reflected by scatterers. Thereby, the selected scatterers and only two real BSs form a complete positioning system. In addition, because MS is motionless in most scenarios, BS must be moving to acquire the Doppler frequency shift. The algorithm proposed in this article is adjusted for the scenarios. And the scatterers with linear constraint can also be utilize fully. Simulation results show the algorithm proposed in this article in two different scenarios, not only simplifies the traditional algorithm, but also achieves the higher positioning accuracy.

关键词： linear constraint Non-line-of-sight Doppler frequency shift Virtual base station

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Randomized Methods for linear constraints: Convergence Rates and Conditioning

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MATHEMATICS OF OPERATIONS RESEARCH 2010年第3期35卷 641-654页

作者： Leventhal, D. Lewis, A. S. Cornell Univ Sch Operat Res & Informat Engn Ithaca NY 14853 USA

We study randomized variants of two classical algorithms: coordinate descent for systems of linear equations and iterated projections for systems of linear inequalities. Expanding on a recent randomized iterated projection algorithm of Strohmer and Vershynin (Strohmer, T., R. Vershynin. 2009. A randomized Kaczmarz algorithm with exponential convergence. J. Fourier Anal. Appl. 15 262-278) for systems of linear equations, we show that, under appropriate probability distributions, the linear rates of convergence (in expectation) can be bounded in terms of natural linear-algebraic condition numbers for the problems. We relate these condition measures to distances to ill-posedness and discuss generalizations to convex systems under metric regularity assumptions.

关键词： coordinate descent linear constraint condition number randomization error bound iterated projections averaged projections distance to ill-posedness metric regularity

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Solution of indefinite linear systems using an LQ decomposition for the linear constraints

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linear ALGEBRA AND ITS APPLICATIONS 2009年第3-4期431卷 381-395页

作者： Schilders, Wil H. A. Corp I&T DTF D PDM Math NXP Semicond Eindhoven Netherlands TU Eindhoven Fac Math & Comp Sci CASA Eindhoven Netherlands

In this paper, indefinite linear systems with linear constraints are considered. We present a special decomposition that makes use of the LQ decomposition, and retains the constraints in the factors. The resulting decomposition is of a structure similar to that obtained using the Bunch-Kaufman-Parlett algorithm. The decomposition can be used in a direct solution algorithm for indefinite systems, but it can also be used to construct effective preconditioners. Combinations of the latter with conjugate gradient type methods have been demonstrated to be very useful. (C) 2009 Elsevier Inc. All rights reserved.

关键词： Indefinite system linear constraint LQ decomposition Bunch-Kaufman-Parlett Conjugate gradients Incomplete preconditioning

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FIR filter designs with linear constraints using the eigenfilter approach

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IEEE TRANSACTIONS ON CIRCUITS AND SYSTEMS II-EXPRESS BRIEFS 1998年第2期45卷 232-237页

作者： Pei, SC Tseng, CC Yang, WS Natl Taiwan Univ Dept Elect Engn Taipei 106 Taiwan

Conventionally, the eigenfilter approach ha been success fully used to design a linear phase FIR filter without adding any constraint, such as a low pass filter, differentiator, and Hilbert transformer. Wen a constraint is incorporated in the eigenfilter design, only some special examples have been considered, The Nyquist filter is a typical example, In this paper, we first develop an eigenfilter approach to design a linear phase FIR filter in conjunction with general linear constraints. Then. He extend the proposed approach to the arbitrary FIR filter design with general linear constraints. Two design examples are presented to demonstrate the effectiveness of our approaches.

关键词： eigenfilter FIR filter linear constraint

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Structural Controller for Logical Expression of linear constraints on Petri Nets

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IEEE TRANSACTIONS ON AUTOMATIC CONTROL 2020年第1期65卷 397-403页

作者： Luo, Jiliang Wu, Weimin Zhou, Mengchu Shao, Hui Nonami, Kenzo Su, Hongye Huaqiao Univ Coll Informat Sci & Engn Xiamen 361021 Peoples R China Fujian Engn Res Ctr Motor Control & Syst Optimal Xiamen 361021 Peoples R China Zhejiang Univ Inst Cyber Syst & Control State Key Lab Ind Control Hangzhou 310027 Peoples R China New Jersey Inst Technol Dept Elect & Comp Engn Newark NJ 07102 USA Chiba Univ Dept Mech Engn Chiba 2638522 Japan

Based on the P-type composition of Petri nets (PNs) defined in this paper, a framework for a structural control of discrete event systems (DESs) is constructed such that a closed-loop PN is obtained by composing a plant PN and a controller. As for a disjunction or conjunctive normal form (CNF) of linear constraints, a new approach is proposed to design a structural controller in this framework. First, a switching-net is defined for a disjunction of constraints, and an extended plant is obtained through the P-type composition of a plant PN and switching-net. Second, the disjunction of bounded constraints is transformed into a conjunction of switching-constraints on the extended plant. Third, a controller is synthesized by designing monitors for conjunctive switching-constraints according to a supervision-based-on-place-invariant method. Fourth, in a similar manner, a controller is also designed for a CNF of bounded constraints. The resulting controller is maximally permissive if each disjunction of constraints meets the jump-free condition, and its size grows polynomially with the number of constraints. Another advantage is that the closed-loop system is still a PN for many real DES since a CNF can describe not only convex but also nonconvex state regions.

关键词： Switches Monitoring Petri nets Closed loop systems Law Controller generalized mutual exclusion constraint (GMEC) linear constraint Petri net (PN)

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COMBINATORIAL METHOD FOR SOLVING SYSTEMS OF linear constraintS

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CYBERNETICS AND SYSTEMS ANALYSIS 2014年第4期50卷 495-506页

作者： Kryvyi, S. L. Taras Shevchenko Natl Univ Kyiv Kiev Ukraine

This article considers a combinatorial method for computing the basis of the set of solutions to systems of linear constraints over the set of real numbers and an improved method for computing a minimal generating set of solutions over the set of natural numbers. A brief review of such methods in other discrete domains is presented.

关键词： linear constraint linear Diophantine constraint basis for a solution set

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A Community-Division Based Algorithm for Finding Relations Among linear constraints 11th

A Community-Division Based Algorithm for Finding Relations A...

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11th International Conference on Knowledge Science, Engineering and Management (KSEM)

作者： Liu, Minghao Ma, Feifei Yan, Jun Chinese Acad Sci Inst Software State Key Lab Comp Sci Beijing Peoples R China Chinese Acad Sci Inst Software Lab Parallel Software & Computat Sci Beijing Peoples R China Chinese Acad Sci Inst Software Technol Ctr Software Engn Beijing Peoples R China Univ Chinese Acad Sci Beijing Peoples R China

ISBN: (纸本)9783319992471;9783319992464

linear constraints are widely used in the modeling of many practical problems, and the solving technologies have important applications in satisfiability modulo theories, program analysis and verification. The efficiency of solving procedure could be improved by taking advantages of the relations among constraints. Traditional methods find relations through search, which do not take advantage of the structural characteristics and cost too much time. In this paper, a heuristic based on community division is proposed for finding relations among linear constraints. Firstly it builds a relation graph, which maps each constraint to a node. Then a division tool is employed to divide the nodes into several communities. At last, it tries to find relations among constraints in the same community through search. Experimental results show that the algorithm can effectively process large set of constraints, reduce time cost and find relations with higher quality.

关键词： linear constraint Relation finding Community division constraint programming

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Diffuse Kalman filtering with linear constraints on the state parameters

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COMMUNICATIONS IN STATISTICS-THEORY AND METHODS 2023年第24期52卷 8884-8893页

作者： Pizzinga, Adrian Fernandes, Marcelo Fluminense Fed Univ UFF Inst Math & Stat Rua Prof Marcos Waldemar Freitas Reis S-NBloco G BR-24210201 Niteroi RJ Brazil Fundacao Getulio Vargas Sao Paulo Sch Econ Escola Econ Sao Paulo Sao Paulo SP Brazil

We give a general proof, based on Piet de Jong's diffuse Kalman filter, that imposing linear constraints on state smoothing is still feasible under diffuse initialization. We also offer simple derivations of exist... 详细信息

关键词： State space model diffuse initialization diffuse Kalman filter linear constraint

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Unified model of boost converter in continuous and discontinuous conduction modes

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IET POWER ELECTRONICS 2016年第10期9卷 2036-2043页

作者： Han, Junfeng Zhang, Bo Qiu, Dongyuan South China Univ Technol Sch Elect Power Guangzhou 510640 Guangdong Peoples R China

Much effort has been made to build appropriate models for a boost converter. However, these models were described as inexact or complicated expressions in both continuous conduction mode (CCM) and discontinuous conduction mode (DCM). This study proposes a new modelling method based on propositional calculus and linear constraint. First, the equivalent operating conditions (OCs) of the boost converter in CCM and DCM are formulated. Second, according to the equivalent translation principle, the OCs of the boost converter in three different modes can be transformed into two linear inequalities. Moreover then, a unified model of the boost converter in CCM and DCM is obtained. Compared with mixed logical dynamical model, the proposed model (PM) of the boost converter is more concise. In addition, the PM is a large-signal model in the theoretical analysis. Finally, the model is simulated in MATLAB under different load conditions and its effectiveness is well verified by simulation results. Moreover, the experimental results are consistent with the simulation results.

关键词： power convertors calculus boost converter unified model continuous conduction mode discontinuous conduction mode CCM DCM load conditions Matlab simulation model PM large-signal model linear inequalities equivalent translation principle equivalent OC equivalent operating conditions propositional calculus linear constraint

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