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THE BLUE AND MINQUE IN GAUSS-MARKOFF MODEL WITH LINEAR TRANSFORMATION OF THE OBSERVABLE VARIABLES
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作者 张宝学 《Acta Mathematica Scientia》 SCIE CSCD 2007年第1期203-210,共8页
For a singular linear model A = (y, Xβ, σ2 V) and its transformed model MF = (Fy, FXβ, σ 2FVF'), where V is nonnegative definite and X can be rank-deficient, the expressions for the differences of the estimat... For a singular linear model A = (y, Xβ, σ2 V) and its transformed model MF = (Fy, FXβ, σ 2FVF'), where V is nonnegative definite and X can be rank-deficient, the expressions for the differences of the estimates for the vector of FXβ and the variance factor σ2 are given. Moreover, the necessary and sufficient conditions for the equalities of the estimates for the vector of FXβ and the variance factor σ2 are also established. In the meantime, works in Baksalary and Kala (1981) are strengthened and consequences in Puntanen and Nurhonen (1992), and Puntanen (1996) are extended. 展开更多
关键词 Singular linear model BLUE MINQUE linear transformation
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On the Group of Units for the Ring of Linear Transformations
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作者 张光辉 孙应德 《Chinese Quarterly Journal of Mathematics》 CSCD 北大核心 2005年第4期355-359,共5页
In this paper, we introduce a practical method for obtaining the structure of thegroup of units for the ring of linear transformations of a vector space over an arbitrary field,and we give a further generalization of ... In this paper, we introduce a practical method for obtaining the structure of thegroup of units for the ring of linear transformations of a vector space over an arbitrary field,and we give a further generalization of the result in [3]. 展开更多
关键词 semidirect product linear transformation normal group BASIS
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A DECOMPOSITION DEPENDED ON DIRECTIONS FOR NONSINGULAR LINEAR TRANSFORMATION
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作者 张慎学 《Applied Mathematics and Mechanics(English Edition)》 SCIE EI 1996年第8期789-794,共6页
In this paper. we give a decomposition depending on p(1≤p≤n-2) orthonormaldirections assigned for nonsingular linear transformation F on a n-dimension (n≥3)Euclidean space En, and then prove foal there exist q(q=n-... In this paper. we give a decomposition depending on p(1≤p≤n-2) orthonormaldirections assigned for nonsingular linear transformation F on a n-dimension (n≥3)Euclidean space En, and then prove foal there exist q(q=n-p) quasi-Principaldirections.for F depending on the preceding p orthonormal directions. As applicance ofthe preceding result, we derive that there exist at least two orthonormal principaldirections of strain in arbitrary plane of body which is in homogeneous deformation,and strain energy density is.function of 5 real numbers under arbitrary quasi-principalbase.for the preceding nonsingular linear transformation. 展开更多
关键词 NONSINGULAR linear transformation quasi-principal directions.Decomposition
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ON THE DECOMPOSITION OF COMPLEX VECTOR SPACES AND THE JORDAN CANONICAL FORM OF COMPLEX LINEAR TRANSFORMATIONS
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作者 肖衡 《Applied Mathematics and Mechanics(English Edition)》 SCIE EI 1994年第11期997-1003,共7页
New objects characterizing the structure of complex linear transformations areintroduced. These new objects yield a new result for the decomposition of complexvector spaces relative to complex lrnear transformations a... New objects characterizing the structure of complex linear transformations areintroduced. These new objects yield a new result for the decomposition of complexvector spaces relative to complex lrnear transformations and provide all Jordan basesby which the Jordan canonical form is constructed. Accordingly, they can result in thecelebrated Jordan theorem and the third decomposition theorem of space directly. and,moreover, they can give a new deep insight into the exquisite and subtle structure ofthe Jordan form. The latter indicates that the Jordan canonical form of a complexlinear transformation is an invariant structure associated with double arbitrary. choices. 展开更多
关键词 complex vector space complex linear transformation. decompo-sition theorems. Jordan canonical form
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Linear Transformation Theory of Quantum Field Operators and Its Applications
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作者 MALei 《Communications in Theoretical Physics》 SCIE CAS CSCD 2003年第3期291-294,共4页
We extend the linear quantum transformation theory to the case of quantum field operators. The corresponding general transformation expressions of CPT transformations and gauge field transformations are considered as ... We extend the linear quantum transformation theory to the case of quantum field operators. The corresponding general transformation expressions of CPT transformations and gauge field transformations are considered as its applications. 展开更多
关键词 linear quantum transformation CPT transformations gauge field transformations
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Optimization Methods for Box-Constrained Nonlinear Programming Problems Based on Linear Transformation and Lagrange Interpolating Polynomials
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作者 Zhi-You Wu Fu-Sheng Bai Jing Tian 《Journal of the Operations Research Society of China》 EI CSCD 2017年第2期193-218,共26页
In this paper,an optimality condition for nonlinear programming problems with box constraints is given by using linear transformation and Lagrange interpolating polynomials.Based on this condition,two new local optim... In this paper,an optimality condition for nonlinear programming problems with box constraints is given by using linear transformation and Lagrange interpolating polynomials.Based on this condition,two new local optimization methods are developed.The solution points obtained by the new local optimization methods can improve the Karush–Kuhn–Tucker(KKT)points in general.Two global optimization methods then are proposed by combining the two new local optimization methods with a filled function method.Some numerical examples are reported to show the effectiveness of the proposed methods. 展开更多
关键词 Nonlinear programming Optimality conditions linear transformation Lagrange interpolating polynomials Global optimization method
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Classical and Quantum Behavior of Generalized Oscillators in Terms of Linear Canonical Transformations
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作者 Akihiro Ogura 《Journal of Modern Physics》 2016年第15期2205-2218,共14页
The quantum mechanical relationships between time-dependent oscillators, Hamilton-Jacobi theory and an invariant operator are clarified by making reference to a system with a generalized oscillator. We introduce a lin... The quantum mechanical relationships between time-dependent oscillators, Hamilton-Jacobi theory and an invariant operator are clarified by making reference to a system with a generalized oscillator. We introduce a linear transformation in position and momentum, and show that the correspondence between classical and quantum transformations is exactly one-to-one. We found that classical canonical transformations are constructed from quantum unitary transformations as long as we are concerned with linear transformations. We also show the relationship between the invariant operator and a linear transformation. 展开更多
关键词 Quantum Canonical transformation linear transformation Generalized Oscillators Invariant Operator
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An Improved Robust Model Predictive Control Approach to Systems with Linear Fractional Transformation Perturbations 被引量:2
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作者 Peng-Yuan Zheng Yu-Geng Xi De-Wei Li 《International Journal of Automation and computing》 EI 2011年第1期134-140,共7页
In this paper, a robust model predictive control approach is proposed for a class of uncertain systems with time-varying, linear fractional transformation perturbations. By adopting a sequence of feedback control laws... In this paper, a robust model predictive control approach is proposed for a class of uncertain systems with time-varying, linear fractional transformation perturbations. By adopting a sequence of feedback control laws instead of a single one, the control performance can be improved and the region of attraction can be enlarged compared with the existing model predictive control (MPC) approaches. Moreover, a synthesis approach of MPC is developed to achieve high performance with lower on-line computational burden. The effectiveness of the proposed approach is verified by simulation examples. 展开更多
关键词 Robust model predictive control linear fractional transformation (LFT) perturbations linear matrix inequalities (LMIs) feedback model predictive control (MPC) framework sequence of feedback control laws.
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From Translation to Linear and Linear Canonical Transformations
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作者 Tan Si Do 《Applied Mathematics》 2022年第6期502-522,共21页
In order to obtain with simplicity the known and new properties of linear canonical transformations (LCTs), we show that any relation between a couple of operators (A,B) having commutator identical to unity, called du... In order to obtain with simplicity the known and new properties of linear canonical transformations (LCTs), we show that any relation between a couple of operators (A,B) having commutator identical to unity, called dual couple in this work, is valuable for any other dual couple, so that from the known translation operator exp(a&#8706;<sub>x</sub>) one may obtain the explicit form and properties of a category of linear and linear canonical transformations in 2N-phase spaces. Moreover, other forms of LCTs are also obtained in this work as so as the transforms by them of functions by integrations as so as by derivations. In this way, different kinds of LCTs such as Fast Fourier, Fourier, Laplace, Xin Ma and Rhodes, Baker-Campbell-Haussdorf, Bargman transforms are found again. 展开更多
关键词 Dual Operators Fundamental Law of Operator Calculus Newtonian Binomial and Translation linear and linear Canonical Transforms From Fourier to Gauss and LCTs’ Transforms
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State Feedback Control for a Class of Fractional Order Nonlinear Systems 被引量:2
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作者 Yige Zhao Yuzhen Wang Haitao Li 《IEEE/CAA Journal of Automatica Sinica》 SCIE EI 2016年第4期483-488,共6页
Using the Lyapunov function method, this paper investigates the design of state feedback stabilization controllers for fractional order nonlinear systems in triangular form, and presents a number of new results. First... Using the Lyapunov function method, this paper investigates the design of state feedback stabilization controllers for fractional order nonlinear systems in triangular form, and presents a number of new results. First, some new properties of Caputo fractional derivative are presented, and a sufficient condition of asymptotical stability for fractional order nonlinear systems is obtained based on the new properties. Then, by introducing appropriate transformations of coordinates, the problem of controller design is converted into the problem of finding some parameters, which can be certainly obtained by solving the Lyapunov equation and relevant matrix inequalities. Finally, based on the Lyapunov function method, state feedback stabilization controllers making the closed-loop system asymptotically stable are explicitly constructed. A simulation example is given to demonstrate the effectiveness of the proposed design procedure. © 2014 Chinese Association of Automation. 展开更多
关键词 Closed loop systems Controllers Differentiation (calculus) linear transformations Lyapunov functions Nonlinear systems STABILIZATION State feedback
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H_∞ Output Feedback Control of Linear Time-invariant Fractional-order Systems over Finite Frequency Range 被引量:1
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作者 Cuihong Wang Huanhuan Li YangQuan Chen 《IEEE/CAA Journal of Automatica Sinica》 SCIE EI 2016年第3期304-310,共7页
This paper focuses on the H∞output feedback control problem of linear time-invariant fractional-order systems over finite frequency range. Based on the generalized Kalman-Yakubovic-Popov (KYP) Lemma and a key project... This paper focuses on the H∞output feedback control problem of linear time-invariant fractional-order systems over finite frequency range. Based on the generalized Kalman-Yakubovic-Popov (KYP) Lemma and a key projection lemma, a necessary and sufficient condition is established to ensure the existence of the H∞output feedback controller over finite frequency range, a desirable property in control engineering practice. By using the matrix congruence transformation, the feedback control gain matrix is decoupled and further parameterized by a scalar matrix. Two iterative linear matrix inequality algorithms are developed to solve this problem. Finally, numerical examples are provided to illustrate the effectiveness of the proposed method. © 2014 Chinese Association of Automation. 展开更多
关键词 ALGEBRA Feedback control Iterative methods linear matrix inequalities linear transformations Matrix algebra Numerical methods
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A Novel Method for Forecasting Freak Wave Occurrence in A Short Crested Coastal Sea
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作者 WANG Ying-guang 《China Ocean Engineering》 SCIE EI CSCD 2024年第1期104-116,共13页
In order to forecast the distribution of crest amplitudes and the occurrence of freak waves in a short crested coastal sea,a novel transformed linear simulation method is initially proposed in this paper.A Hermite tra... In order to forecast the distribution of crest amplitudes and the occurrence of freak waves in a short crested coastal sea,a novel transformed linear simulation method is initially proposed in this paper.A Hermite transformation model expressed as a monotonic cubic polynomial serves as the foundation for the novel simulation technique.The wave crest amplitude exceedance probabilities of two sea states-one with a directional wave spectrum based on the measured wave elevation data at the Yura coast and the other with a typical directional JONSWAP wave spectrum-have been predicted using the novel simulation method that has been proposed.The likelihood that a particular critical wave crest amplitude will be exceeded is directly correlated with the probability that freak waves will occur.It is shown that the novel simulation approach suggested can provide predictions that are more precise than those obtained from the Rayleigh crest amplitude distribution model,the Jahns and Wheeler crest amplitude distribution model,or the conventional linear simulation method.This study also demonstrated that the nonlinear simulation method is less effective than the novel simulation method in terms of efficiency. 展开更多
关键词 wave crest amplitude freak waves short crested sea transformed linear simulation
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Inverse problem in linear algebra
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作者 Cao Ying 《International Journal of Technology Management》 2015年第1期111-113,共3页
With the increasingly widespread application of linear algebra theory, and in its opposite direction is not enough emphasis, linear algebra, several important points: matrix, determinant, linear equations, linear tra... With the increasingly widespread application of linear algebra theory, and in its opposite direction is not enough emphasis, linear algebra, several important points: matrix, determinant, linear equations, linear transformations, matrix keratosis and other anti-deepening understanding of the basics and improve the comprehensive ability to solve problems. 展开更多
关键词 linear algebra the inverse problem MATRIX DETERMINANT linear equations linear transformation
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Research on the File Encryption and Programming based on Matrix Transformation
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作者 Jiangtao Geng Qi Huang 《International Journal of Technology Management》 2013年第1期24-26,共3页
Any linear transform matrix can be used to easily calculate a consistent form, and a plurality of conversion can be easily connected together by matrix multiplication. When performing file transfers, you can encrypt f... Any linear transform matrix can be used to easily calculate a consistent form, and a plurality of conversion can be easily connected together by matrix multiplication. When performing file transfers, you can encrypt files matrix transformation. Article presents a matrix-based electronic document encryption and decryption algorithm, which relies on a special class of matrices combinatorial problems, the method to improve the security of electronic document system is feasible and effective, and finally give the source code and programming software. 展开更多
关键词 linear transformation file encryption and decryption matrix vc source code
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A Multi-Gap Multi-Channel Gas Switch for the Linear Transformer Driver 被引量:3
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作者 刘轩东 梁天学 +4 位作者 孙凤举 姜晓峰 李佳 孙福 邱爱慈 《Plasma Science and Technology》 SCIE EI CAS CSCD 2009年第6期725-729,共5页
A multi-gap and multi-channel gas switch with convexo-convex discal planet electrodes was designed and investigated. Eight gaps are formed in series by a trigger electrode, six intermediate electrodes and two high vol... A multi-gap and multi-channel gas switch with convexo-convex discal planet electrodes was designed and investigated. Eight gaps are formed in series by a trigger electrode, six intermediate electrodes and two high voltage electrodes with a uniform gap length of 5 ram. The self breakdown and triggered breakdown performance of the switch are reported. Both the delay time and jitter decrease with the increase in the trigger voltage, switching coefficient and the decrease in the trigger isolating resistor. The delay time of the switch is about 40 ns, and the jitter is less than 2 ns when charged with 4-85 kV and triggered by a voltage pule of -75 kV. The inductance of the switch is about 30 nH. 展开更多
关键词 multi-gap multi-channel gas spark closing switch linear transformer driver delay time JITTER
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Numerical Analysis of the Output-Pulse Shaping Capability of Linear Transformer Drivers 被引量:2
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作者 刘鹏 孙风举 +1 位作者 尹佳辉 邱爱慈 《Plasma Science and Technology》 SCIE EI CAS CSCD 2011年第2期246-251,共6页
Output-pulse shaping capability of a linear transformer driver (LTD) module under different conditions is studied, by conducting the whole circuit model simulation by using the PSPICE code. Results indicate that a h... Output-pulse shaping capability of a linear transformer driver (LTD) module under different conditions is studied, by conducting the whole circuit model simulation by using the PSPICE code. Results indicate that a higher impedance profile of the internal transmission line would lead to a wider adjustment range for the output current rise time and a narrower adjustment range for the current peak. The number of cavities in series has a positive effect on the output- pulse shaping capability of LTD. Such an improvement in the output-pulse shaping capability can primarily be ascribed to the increment in the axial electric length of LTD. For a triggering time interval longer than the time taken by a pulse to propagate through the length of one cavity, the output parameters of LTD could be improved significantly. The present insulating capability of gas switches and other elements in the LTD cavities may only tolerate a slightly longer deviation in the triggering time interval. It is feasible for the LTD module to reduce the output current rise time, though it is not useful to improve the peak power effectively. 展开更多
关键词 linear transformer driver (LTD) circuit model pulsed power transmission line impedance profile trigger delay
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Influences of Switching Jitter on the Operational Performances of Linear Transformer Drivers-Based Drivers 被引量:2
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作者 刘鹏 孙凤举 +3 位作者 魏浩 王志国 尹佳辉 邱爱慈 《Plasma Science and Technology》 SCIE EI CAS CSCD 2012年第4期347-352,共6页
A whole circuit model of a linear transformer drivers (LTD) module composed of 60 cavities in series was developed in the software PSPICE to study the influence of switching jitter on the operational performances of... A whole circuit model of a linear transformer drivers (LTD) module composed of 60 cavities in series was developed in the software PSPICE to study the influence of switching jitter on the operational performances of LTDs. In the model, each brick in each cavity is capable of operating with jitter in its switch. Additionally, the manner of triggering cables entering into cavities was considered. The performances of the LTD module operating with three typical cavity-triggering sequences were simulated and the simulation results indicate that switching jitter affects slightly the peak and starting time of the output current pulse. However, the enhancement in switching jitter would significantly lengthen the rise time of the output current pulse. Without considering other factors, a jitter lower than 10 ns may be necessary for the switches in the LTD module to provide output current parameters with an acceptable deviation. 展开更多
关键词 linear transformer drivers (LTDs) circuit model pulsed power transmission line JITTER trigger delay
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Uncertainty Principle for the Quaternion Linear Canonical Transform in Terms of Covariance 被引量:2
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作者 Yanna Zhang 《Journal of Beijing Institute of Technology》 EI CAS 2021年第3期238-243,共6页
An uncertainty principle(UP),which offers information about a signal and its Fourier transform in the time-frequency plane,is particularly powerful in mathematics,physics and signal processing community.Under the pola... An uncertainty principle(UP),which offers information about a signal and its Fourier transform in the time-frequency plane,is particularly powerful in mathematics,physics and signal processing community.Under the polar coordinate form of quaternion-valued signals,the UP of the two-sided quaternion linear canonical transform(QLCT)is strengthened in terms of covariance.The condition giving rise to the equal relation of the derived result is obtained as well.The novel UP with covariance can be regarded as one in a tighter form related to the QLCT.It states that the product of spreads of a quaternion-valued signal in the spatial domain and the QLCT domain is bounded by a larger lower bound. 展开更多
关键词 uncertainty principle quaternion linear canonical transform quaternion-valued signals COVARIANCE
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Optical Diagnostics of Multi-Gap Gas Switches for Linear Transformer Drivers 被引量:1
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作者 盛亮 李阳 +7 位作者 孙铁平 丛培天 张美 彭博栋 赵吉祯 岳志勤 魏福利 袁媛 《Plasma Science and Technology》 SCIE EI CAS CSCD 2014年第7期677-682,共6页
The trigger characteristics of a multi-gap gas switch with double insulating layers,a square-groove electrode supporter and a UV pre-ionizing structure are investigated aided by a high sensitivity fiber-bundle array d... The trigger characteristics of a multi-gap gas switch with double insulating layers,a square-groove electrode supporter and a UV pre-ionizing structure are investigated aided by a high sensitivity fiber-bundle array detector, a UV fiber detector, and a framing camera, in addition to standard electrical diagnostics. The fiber-bundle-array detector is used to track the turn-on sequence of each electrode gap at a timing precision of 0.6 ns. Each fiber bundle, including five fibers with different azimuth angles, aims at the whole emitting area of each electrode gap and is fed to a photomultiplier tube. The UV fiber detector with a spectrum response of 260-320 nm,including a fused-quartz fiber of 200 μm in diameter and a solar-blinded photomultiplier tube, is adopted to study the effect of UV pre-ionizing on trigger characteristics. The framing camera,with a capacity of 4 frames per shot and an exposure time of 5 ns, is employed to capture the evolution of channel arcs. Based on the turn-on light signal of each electrode gap, the breakdown delay is divided into statistical delay and formative delay. A decrease in both of them, a smaller switch jitter and more channel arcs are observed with lower gas pressure. An increase in trigger voltage can reduce the statistical delay and its jitter, while higher trigger voltage has a relatively small influence on the formative delay and the number of channel arcs. With the UV pre-ionizing structure at 0.24 MPa gas pressure and 60 kV trigger voltage, the statistical delay and its jitter can be reduced by 1.8 ns and 0.67 ns, while the formative delay and its jitter can only be reduced by 0.5 ns and 0.25 ns. 展开更多
关键词 optical diagnostics multi-gap gas switches linear transformer driver
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Research Progress on Discretization of Linear Canonical Transform
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作者 Yannan Sun Bingzhao Li Ran Tao 《Journal of Beijing Institute of Technology》 EI CAS 2021年第3期205-216,共12页
Linear canonical transformation(LCT)is a generalization of the Fourier transform and fractional Fourier transform.The recent research has shown that the LCT is widely used in signal processing and applied mathematics,... Linear canonical transformation(LCT)is a generalization of the Fourier transform and fractional Fourier transform.The recent research has shown that the LCT is widely used in signal processing and applied mathematics,and the discretization of the LCT becomes vital for the applic-ations of LCT.Based on the development of discretization LCT,a review of important research progress and current situation is presented,which can help researchers to further understand the discretization of LCT and can promote its engineering application.Meanwhile,the connection among different discretization algorithms and the future research are given. 展开更多
关键词 linear canonical transform(LCT) discrete linear canonical transform sampling Wign-er-Ville distribution fast algorithm
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