• Title/Summary/Keyword: 유사 역행렬

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A Neural-like Algorithm to Compute One-Sided Inverse of III-Conditioned Matrices (III-Conditioned 정방행렬의 단측 역행렬 산출용 유사 인공신경망 알고리듬)

  • 문병수;양성운;김영택
    • Proceedings of the Korean Information Science Society Conference
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    • 1998.10c
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    • pp.321-323
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    • 1998
  • 이 논문에서는 크기가 큰 III-Conditioned Matrices 정방행렬의 좌측 또는 우측 역행렬 계산시 계산상의 정확도를 향상시키는 알고리듬에 대하여 기술한다. 이 알고리듬은 대상 행렬의 행벡터들을 Input으로 하고 해당 Input 벡터가 몇번째 행 벡터인지를 나타내는 단위 벡터를 Target 벡터로 하며 초기 Weight 값으로 Pivoting을 겸한 Gauss소거법을 적용하여 얻은 역행렬을 사용하는 Single Layer 인공신경망에 적용하는 역전파 알고리듬과 흡사한 것이다. 각각의 Input 행 벡터에 대하여 역행렬의 열 벡터들이 점진적으로 직교가 되거나 평행이 되도록 근접시키므로써 모든 Input 행 벡터들이 열벡터들에 비교적 균일하게 직교 또는 평행이 되도록 학습시키는 알고리듬이다.

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A New Pseudoinverse Matrix Method For Balancing Chemical Equations And Their Stability (화학반응식 균형과 안정성을 위한 새로운 유사 역행렬법)

  • Risteski, Ice B.
    • Journal of the Korean Chemical Society
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    • v.52 no.3
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    • pp.223-238
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    • 2008
  • this work is given a new pseudoniverse matrix method for balancing chemical equations. Here offered method is founded on virtue of the solution of a Diophantine matrix equation by using of a Moore-Penrose pseudoinverse matrix. The method has been tested on several typical chemical equations and found to be very successful for the all equations in our extensive balancing research. This method, which works successfully without any limitations, also has the capability to determine the feasibility of a new chemical reaction, and if it is feasible, then it will balance the equation. Chemical equations treated here possess atoms with fractional oxidation numbers. Also, in the present work are introduced necessary and sufficient criteria for stability of chemical equations over stability of their extended matrices.

Position and Vibration Control of a Spatial Redundant Flexible Manipulator by using Pseudo-inverse of Jacobian (유사 역행렬을 이용한 여유자유도 3차원 유연 매니퓰레이터의 위치 및 진동제어)

  • Kim, Jin-Su
    • Journal of the Korean Society for Precision Engineering
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    • v.18 no.12
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    • pp.66-72
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    • 2001
  • In this paper, by using pseudo-inverse matrix of the spatial redundant flexible manipulators, a position control method and its effect in vibration suppression was presented. Vibration suppression control was developed using lumped mass spring model of the flexible manipulators. With 2 elastic links and 7 rotory joint manipulator ADAM, (1)position control for no redundancy, and (2)position control for one redundant DOF(degree of freedom) were tested. The objective of this experiment is to show the effect of position control, using pseudo-inverse matrix. toward the improvement of operation, and at the same time, to reduce the vibration of the link and the magnitude of the joint torque.

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An time-varying acoustic channel estimation using least squares algorithm with an average gradient vector based a self-adjusted step size and variable forgetting factor (기울기 평균 벡터를 사용한 가변 스텝 최소 자승 알고리즘과 시변 망각 인자를 사용한 시변 음향 채널 추정)

  • Lim, Jun-Seok
    • The Journal of the Acoustical Society of Korea
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    • v.38 no.3
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    • pp.283-289
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    • 2019
  • RLS (Recursive-least-squares) algorithm is known to have good convergence and excellent error level after convergence. However, there is a disadvantage that numerical instability is included in the algorithm due to inverse matrix calculation. In this paper, we propose an algorithm with no matrix inversion to avoid the instability aforementioned. The proposed algorithm still keeps the same convergence performance. In the proposed algorithm, we adopt an averaged gradient-based step size as a self-adjusted step size. In addition, a variable forgetting factor is introduced to provide superior performance for time-varying channel estimation. Through simulations, we compare performance with conventional RLS and show its equivalency. It also shows the merit of the variable forgetting factor in time-varying channels.

BCDR algorithm for network estimation based on pseudo-likelihood with parallelization using GPU (유사가능도 기반의 네트워크 추정 모형에 대한 GPU 병렬화 BCDR 알고리즘)

  • Kim, Byungsoo;Yu, Donghyeon
    • Journal of the Korean Data and Information Science Society
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    • v.27 no.2
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    • pp.381-394
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    • 2016
  • Graphical model represents conditional dependencies between variables as a graph with nodes and edges. It is widely used in various fields including physics, economics, and biology to describe complex association. Conditional dependencies can be estimated from a inverse covariance matrix, where zero off-diagonal elements denote conditional independence of corresponding variables. This paper proposes a efficient BCDR (block coordinate descent with random permutation) algorithm using graphics processing units and random permutation for the CONCORD (convex correlation selection method) based on the BCD (block coordinate descent) algorithm, which estimates a inverse covariance matrix based on pseudo-likelihood. We conduct numerical studies for two network structures to demonstrate the efficiency of the proposed algorithm for the CONCORD in terms of computation times.

A Three-Dimensional Galerkin-FEM Model Using Similarity Transform Technique (유사변환기법을 이용한 Galerkin-FEM모델)

  • 강관수;소재귀;정경태
    • Journal of Korean Society of Coastal and Ocean Engineers
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    • v.6 no.2
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    • pp.174-185
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    • 1994
  • This paper presents a modal solution of linear three-dimensional hydrodynamic equations using similarity transform technique. The solution over the vertical space domain is obtained using the Galerkin method with linear shape funtions (Galerkin-FEM model). Application of similarity transform to resulting tri-diagonal matrix equations gives rise 掠 a set of uncoupled partial differential equations of which the unknowns are coefficients of mode shape vectors. The proposed method.

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Improving the Performance of the Capon Algorithm by Nulling Elements of an Inverse Covariance Matrix (공분산 역행렬 원소 제거 기법을 이용한 Capon 알고리듬의 성능 개선)

  • Kim, Seong-Min;Kang, Dong-Hoon;Lee, Yong-Wook;Nah, Sun-Phil;Oh, Wang-Rok
    • Journal of the Institute of Electronics Engineers of Korea SP
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    • v.48 no.5
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    • pp.96-101
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    • 2011
  • It is well known that the Capon algorithm offers better resolution compared to that of the FM (Fourier method) algorithm by minimizing the total output power while maintaining a constant gain in the look direction. Unfortunately, the DoA (Direction of Arrival) estimation performance of the Capon algorithm is drastically degraded when the SNR of received signal is low and thus, it cannot distinguish among signal sources which have similar incidence angles. In this paper, we propose a novel scheme enhancing the resolution of the Capon algorithm by ing all rows except the first row of an inverse covariance matrix.

The Performance Analysis of the Pseudo-decorrelator for WCDMA systems (WCDMA 시스템을 위한 유사 역상관기의 성능 분석)

  • 박중후;이용업
    • The Journal of the Acoustical Society of Korea
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    • v.21 no.2
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    • pp.120-127
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    • 2002
  • As a new type of a linear decorrelating receiver, the Pseudo-Decorrelator was presented for asynchronous code division multiple access systems by the author. In this paper, the concept of the Pseudo-Decorrelator is extended to derive a multiuser receiver for WCDMA uplink systems over a Rayleigh fading multipath channel. Starting with the analysis of the multiple access components of the decision statistics, a non-square cross-correlation matrix for each bit is obtained. This cross-correlation matrix is then inverted, and the inverted matrix is applied to the decision statistics obtained from a conventional receiver. This receiver is near-far resistant and outperforms conventional receivers even for the cases in which synchronization errors, such as time delay errors and phase errors exist.

The Reduction or computation in MLLR Framework using PCA or ICA for Speaker Adaptation (화자적응에서 PCA 또는 ICA를 이용한 MLLR알고리즘 연산량 감소)

  • 김지운;정재호
    • The Journal of the Acoustical Society of Korea
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    • v.22 no.6
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    • pp.452-456
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    • 2003
  • We discuss how to reduce the number of inverse matrix and its dimensions requested in MLLR framework for speaker adaptation. To find a smaller set of variables with less redundancy, we adapt PCA (principal component analysis) and ICA (independent component analysis) that would give as good a representation as possible. The amount of additional computation when PCA or ICA is applied is as small as it can be disregarded. 10 components for ICA and 12 components for PCA represent similar performance with 36 components for ordinary MLLR framework. If dimension of SI model parameter is n, the amount of computation of inverse matrix in MLLR is proportioned to O(n⁴). So, compared with ordinary MLLR, the amount of total computation requested in speaker adaptation is reduced by about 1/81 in MLLR with PCA and 1/167 in MLLR with ICA.

A study on robust recursive total least squares algorithm based on iterative Wiener filter method (반복형 위너 필터 방법에 기반한 재귀적 완전 최소 자승 알고리즘의 견실화 연구)

  • Lim, Jun Seok
    • The Journal of the Acoustical Society of Korea
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    • v.40 no.3
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    • pp.213-218
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    • 2021
  • It is known that total least-squares method shows better estimation performance than least-squares method when noise is present at the input and output at the same time. When total least squares method is applied to data with time series characteristics, Recursive Total Least Squares (RTS) algorithm has been proposed to improve the real-time performance. However, RTLS has numerical instability in calculating the inverse matrix. In this paper, we propose an algorithm for reducing numerical instability as well as having similar convergence to RTLS. For this algorithm, we propose a new RTLS using Iterative Wiener Filter (IWF). Through the simulation, it is shown that the convergence of the proposed algorithm is similar to that of the RTLS, and the numerical robustness is superior to the RTLS.