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A Numerical Approach To Generalized Periodic Sylvester Matrix Equation

ASIAN JOURNAL OF CONTROL 2019年第5期21卷 2468-2475页

作者： Lv, Lingling Zhang, Zhe North China Univ Water Resources & Elect Power Inst Elect Power Zhengzhou 450011 Henan Peoples R China

The paper is dedicated to solving the generalized periodic discrete-time Sylvester matrix equation, which is frequently encountered in control theory and applied mathematics. An iterative algorithm for this equation is presented. The proposed method is developed from a point of least squares method. The rationality of the method is testified by theoretical analysis. The presented approach is numerically reliable and requires less computation. Two numerical examples illustrate the effectiveness of the raised results.

关键词： Generalized periodic Sylvester matrix equations least squares method iterative algorithm numerical solutions

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Energy efficient joint energy cooperation and power allocation in multiuser distributed antenna systems with hybrid energy supply

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IET COMMUNICATIONS 2019年第2期13卷 153-161页

作者： Zhu, Pengcheng Mao, Huanhuan Li, Jiamin You, Xiaohu Southeast Univ Natl Mobile Commun Res Lab Nanjing 210096 Jiangsu Peoples R China

This study investigates the joint power allocation and energy cooperation problem in a multiuser downlink distributed antenna system with hybrid energy supply. The authors focus on the energy efficiency (EE) maximization problem for three different types of precoding, zero-forcing (ZF), general beamforming method and conjugate-beamforming. For ZF precoding, they apply fractional programming and reform the optimization problem to a convex one. An iterative algorithm to deal with the fractional objective function is presented. Whereas the problem is non-convex for general beamforming with user interference, they take maximum ratio transmission as an example and adopt a set of transformation and approximation based on the difference of convex (DC) programming. Furthermore, for conjugate-beamforming, they first transform the quadratic signal to interference plus noise power ratio into a trackable form and then DC programming is applied. A two-loop algorithm for the general beamforming and conjugate-beamforming is presented with fractional programming in the inner loop and DC programming in the outer loop. Simulations show that the proposed algorithm improved EE significantly and indicate that energy cooperation can contribute to a higher EE. It also reveals that ZF achieves better EE with small noise variance while conjugate beamforming in high noise circumstance.

关键词： telecommunication power management precoding concave programming convex programming radiofrequency interference energy conservation antenna arrays iterative methods array signal processing multi-access systems approximation theory noise variance while conjugate beamforming energy efficient joint energy cooperation hybrid energy supply multiuser downlink energy efficiency maximisation problem general beamforming method conjugate-beamforming ZF precoding user interference fractional programming optimisation problem fractional objective function convex programming interference plus noise power ratio DC programming multiuser distributed antenna systems smart grid joint power allocation and energy cooperation problem iterative algorithm nonconvex problem maximum ratio transmission quadratic signal to interference plus noise power ratio two-loop algorithm

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Reliability analysis of standby systems with multi-state elements subject to constant transition rates

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QUALITY AND RELIABILITY ENGINEERING INTERNATIONAL 2019年第1期35卷 318-328页

作者： Jia, Heping Levitin, Gregory Ding, Yi Song, Yonghua Zhejiang Univ Coll Elect Engn Hangzhou Zhejiang Peoples R China Israel Elect Corp Ltd Haifa Israel Univ Macau Dept Elect & Comp Engn Macau Peoples R China

Standby redundancy has been extensively applied to critical engineering systems to enhance system reliability. Researches on reliability evaluation for standby systems focus more on systems with binary-state elements. However, multi-state elements with different performances have played a significant role in engineering systems. This paper presents an approach for reliability analysis of standby systems composed of multi-state elements with constant state transition rates and absorbing failure states. The approach allows modelling different standby systems beyond cold, warm and hot ones by taking into account differences in possible maintenance of elements in standby and operation modes and dependence of elements' operational behavior on their initial state at the time of activation. An iterative algorithm for reliability evaluation based on element state probabilities is suggested. Illustrating examples of evaluating reliability of different types of homogeneous and heterogeneous standby systems are demonstrated.

关键词： constant transition rates iterative algorithm multi-state elements reliability analysis standby systems

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Finite iterative Hamiltonian solutions of the generalized coupled Sylvester - conjugate matrix equations

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TRANSACTIONS OF THE INSTITUTE OF MEASUREMENT AND CONTROL 2019年第4期41卷 1139-1148页

作者： Bayoumi, Ahmed M. E. Ain Shams Univ Dept Math Fac Educ Cairo Egypt

In this paper, we present an iterative algorithm to solve a generalized coupled Sylvester - conjugate matrix equations over Hamiltonian matrices. When the considered systems of matrix equations are consistent, it is proven that the solution can be obtained within finite iterative steps for any arbitrary initial generalized Hamiltonian matrices in the absence of round off errors. Two numerical examples are given to illustrate the effectiveness of the proposed method.

关键词： Coupled Sylvester - conjugate matrix equation iterative algorithm inner product Frobenius norm Hamiltonian solutions

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PySCF-NAO: An efficient and flexible implementation of linear response time-dependent density functional theory with numerical atomic orbitals

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COMPUTER PHYSICS COMMUNICATIONS 2019年 236卷 188-204页

作者： Koval, Peter Barbry, Marc Sanchez-Portal, Daniel Univ Basque Country CSIC Ctr Fis Mat Paseo Manuel de Lardizabal 5 Donostia San Sebastian 20018 Spain Donostia Int Phys Ctr Paseo Manuel de Lardizabal 4 Donostia San Sebastian 20018 Spain

We present an algorithm and its implementation to calculate the properties of electronic excitations in molecules and clusters from first principles, using time-dependent density functional theory (TDDFT). The algorithm assumes the use of some localized functions as a basis set to represent the spatial degrees of freedom. It relies on an iterative computation of the induced density according to the Dyson-like equation for the linear response function. The current implementation is built upon so-called numerical atomic orbitals. It is suitable for a wide variety of density functional theory (DFT) software. In this work, we demonstrate TDDFT calculations starting from preceding DFT runs with SIESTA, GPAW and PySCF packages, while a coupling with the other DFT packages such as Fireball and OpenMX is planned. The mentioned packages are capable of performing ab initio molecular dynamics simulations, and the speed of our TDDFT implementation makes feasible to perform a configuration average of the optical absorption spectra. Our code is written mostly in Python language allowing for a quick and compact implementation of most numerical methods and data-managing tasks with the help of NumPy/SciPy libraries and Python intrinsic constructs. Part of the code is written in C and Fortran to achieve a competitive speed in particular sections of the algorithm. Many parts of the current algorithm and implementation are useful in other ab initio methods for electronic excited states, such as Hedin's GW, Bethe-Salpeter equation and DFT with hybrid functionals. Corresponding proof-of-principles implementations are already part of the code. Program summary Program Title: PySCF-NAO Program Files doi: http://***/10.17632/9wgp6255hn.1 Licensing provisions: Apache License, Version 2.0 Programming language: Python (2 or 3), Fortran90 and C Supplementary material: We provide the source code and input files to organize example and benchmark calculations discussed in the paper. Nature o

关键词： Numerical atomic orbitals Dominant product basis Time-dependent density functional theory iterative algorithm

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Disturbance-observer-based LQR control of singularly perturbed systems via recursive decoupling methods

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INTERNATIONAL JOURNAL OF SYSTEMS SCIENCE 2019年第4期50卷 764-776页

作者： Xu, Jing Niu, Yugang East China Univ Sci & Technol Minist Educ Key Lab Adv Control & Optimizat Chem Proc Shanghai 200237 Peoples R China

This paper addresses the disturbance-observer-based linear quadratic regulation (LQR) problem of singularly perturbed systems subject to harmonic disturbances. To reduce the computational burden and facilitate the on-board implementation, a recursive matrix decoupling method is proposed to decompose the stiff singularly perturbed model into the block-diagonal form. Then, a robust LQR controller is designed based on the equivalent decoupled system, which consists of a state feedback controller for performance optimisation and a robust controller for disturbance compensation. Moreover, the designed controller is integrated with a finite frequency disturbance observer to attenuate the effect of harmonic disturbances. Finally, a simulation example on a DC motor system is provided to verify the effectiveness of the proposed design method.

关键词： Disturbance observer iterative algorithm LQR control singularly perturbed systems

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Design and Implementation of Adaptive Multi-Tap Analog Interference Canceller

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IEEE TRANSACTIONS ON WIRELESS COMMUNICATIONS 2019年第3期18卷 1698-1706页

作者： Zhang, Liyuan Ma, Meng Jiao, Bingli Peking Univ Sch Elect Engn & Comp Sci Beijing 100871 Peoples R China

Due to the severity of self-interferences, analog interference canceller is an essential part of a full duplex radio system. As the self-interference can potentially be even much stronger than the received signal, it must be meritoriously suppressed before analog-to-digital conversion. This paper is aimed to provide an optimal radio frequency domain multi-tap interference cancellation design. To this end, the following two key problems are addressed: the hardware design problem and the adaptive weight adjusting problem. For optimal hardware design, a trade-off between widening effective delay range and maximizing the minimum cancellation capability is formulated. The principles and guidelines for optimal solution and hardware parameter design are derived. We also formulate adaptive weight adjusting as a multi-dimensional optimization problem, which is proved to be non-convex while adjusting the attenuators and phase shifters independently. By using a coordinate transformation technique, it is then converted into a convex optimization problem, and a convergent iterative algorithm based on the gradient descent method is applied to obtain the global optimum. The hardware implementation and experimental results substantiated the effectiveness of the proposed principles and algorithms.

关键词： Full-duplex self-interference cancellation convex optimization problem iterative algorithm

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Synchronous full-field measurement of temperature and deformation based on separated radiation and reflected light

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OPTICS AND LASERS IN ENGINEERING 2019年第May期116卷 94-102页

作者： Tang, Yunlong Yue, Mengkun Fang, Xufei Feng, Xue Tsinghua Univ Dept Engn Mech AML Beijing 100084 Peoples R China Tsinghua Univ Ctr Mech & Mat Beijing 100084 Peoples R China

Optical method has been playing an important role in measuring temperature and deformation at elevated temperatures. Here we propose a simple and effective iterative algorithm to realize accurate and simultaneous measurement of the full-field temperature and deformation of specimens subjected to flame heating at temperatures up to 1000 degrees C. The algorithm separates the optical images of specimen surface into radiant and reflected parts. The radiant part is used to calculate the full-field temperature by an improved two-color method, and the reflected part is used to obtain the deformation of the specimen surface based on high-temperature digital image correlation method. Experimental validation shows that the proposed method can effectively eliminate the mutual interference between the radiation and reflected light, displaying great potential for synchronous measurement of temperature and deformation with sufficient accuracy by using one camera.

关键词： iterative algorithm Synchronous temperature and deformation measurement Separation of radiation and reflected light Two-color method

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Fast algorithms for Designing Complementary Sets of Sequences Under Multiple Constraints

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IEEE ACCESS 2019年 7卷 50041-50051页

作者： Wu, Zhong-Jie Xu, Tian-Liang Zhou, Zhi-Quan Wang, Chen-Xu Harbin Inst Technol Sch Elect & Informat Engn Harbin 150001 Heilongjiang Peoples R China Harbin Inst Technol Sch Informat Sci & Engn Weihai 264209 Peoples R China

Complementary sets of sequences (CSSs) are widely used in many applications, such as active sensing and wireless communication. The construction of CSS has attracted considerable attention over the past few decades. In this paper, efficient and comprehensive computational algorithms for CSS design are proposed. We seek to minimize complementary integral sidelobe level (CISL) under multiple constraints, including unimodular, peak-to-average power ratio, discrete phase, and spectrum compatible constraint. The task of CSS design can be formulated as solving a nonconvex constraint optimization problem. As this problem is difficult to tackle directly, we resort to the general majorization-minimization (MM) method. By utilizing the inherent algebraic structure of the objective function, we construct the majorizing function via two consecutive applications of the MM method and obtain a closed-form solution by a couple of FFT operations at each iteration. The relationship between MM-based algorithms and derivative-based algorithms is revealed. Our algorithms are more flexible and widely applicable, and the numerical experiment results demonstrate the effectiveness and superiority over the existing state-of-art algorithms.

关键词： Waveform design complementary set of sequences correlation iterative algorithm majorization-minimization

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Stabilization for Rectangular Descriptor Fractional Order Systems

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IEEE ACCESS 2019年 7卷 177556-177561页

作者： Liu, Huanxia Lin, Chong Chen, Bing Geng, Wentao Qingdao Univ Inst Complex Sci Qingdao 266071 Peoples R China

This paper focuses on the stabilization problem for rectangular descriptor fractional order systems (FOSs) with 0 < alpha <= 1. Firstly, a fractional order dynamic compensator is constructed to make the closed-loop systems square descriptor FOSs. Secondly, two types of input signals of the compensator are considered, which are state input signal case and output input signal case. Thirdly, a necessary and sufficient condition is proposed for the state input signal case, while a new method of controller design is given for the output input signal case in which the output matrix of the system need not to be full row rank, which reduces the conservativeness of existing methods. Finally, an efficient iterative algorithm for solving the resultant matrix inequalities is proposed, and a numerical example is offered to verify the advantage and feasibility of the results.

关键词： Rectangular descriptor FOS stabilization fractional order dynamic compensator iterative algorithm

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