• Title/Summary/Keyword: 선형변환

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State Feedback Linearization of Discrete-Time Nonlinear Systems via T-S Fuzzy Model (T-S 퍼지모델을 이용한 이산 시간 비선형계통의 상태 궤환 선형화)

  • Kim, Tae-Kue;Wang, Fa-Guang;Park, Seung-Kyu;Yoon, Tae-Sung;Ahn, Ho-Kyun;Kwak, Gun-Pyong
    • Journal of the Korean Institute of Intelligent Systems
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    • v.19 no.6
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    • pp.865-871
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    • 2009
  • In this paper, a novel feedback linearization is proposed for discrete-time nonlinear systems described by discrete-time T-S fuzzy models. The local linear models of a T-S fuzzy model are transformed to a controllable canonical form respectively, and their T-S fuzzy combination results in a feedback linearizable Tagaki-Sugeno fuzzy model. Based on this model, a nonlinear state feedback linearizing input is determined. Nonlinear state transformation is inferred from the linear state transformations for the controllable canonical forms. The proposed method of this paper is more intuitive and easier to understand mathematically compared to the well-known feedback linearization technique which requires a profound mathematical background. The feedback linearizable condition of this paper is also weakened compared to the conventional feedback linearization. This means that larger class of nonlinear systems is linearizable compared to the case of classical linearization.

Medical Image Compression in the Wavelet Transform Domain (Wavelet 변환 영역에서 의료영상압축)

  • 이상복;신승수
    • The Journal of the Korea Contents Association
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    • v.2 no.4
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    • pp.23-29
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    • 2002
  • This paper suggest the image compression that is needed to process PACS in medical information system. The image decoding method is used Linear-predictor and Lloyd-Max quantizer(quantization) in the Wavelet transform domain. Wavelet Transform Method is processed the multi-resolution by dividing image into 10 sub-bands of 3 levels. Low frequency domain that is sensitive to human visual characteristic is encoded by DPCM which is lossless encoding methods, and Lloyed-Max quantizer, the optimal quantizer for reducing ringing and aliasing in the image of inter sub-band, is used in the remaining high frequency domain of sub-band. The examination verifies that decompressed images are superior by the result that PSNR is 28.53dB on the input image, 512$\times$152 abdominal CT image and Chest image.

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A New Wavelet Watermarking Based on Linear Bit Expansion (선형계수확장 기반의 새로운 웨이블릿 워터마킹)

  • Piao Yong-Ri;Kim Seok-Tae
    • Proceedings of the Korean Institute of Information and Commucation Sciences Conference
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    • 2006.05a
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    • pp.167-170
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    • 2006
  • This study proposes a new wavelet watermark technique based on the Linear Bit Expansion. To ensure the security of the watermark, it is Amold Transformed before embedding. Then the wavelet transformation of watermark and original images is processed. Since the size of the watermark image is a quarter of the original site, it uses linear bit-expansion to enlarge the watermark image. Lastly, watermark is inserted in a given intensity to the corresponding low frequency subbands of the wavelet-transformed images proposed in this paper. When detecting the presence of watermark, the similarity between extracted watermark and the original watermark is compared applying the F norm function.

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Voice Personality Transformation Using an Optimum Classification and Transformation (최적 분류 변환을 이용한 음성 개성 변환)

  • 이기승
    • The Journal of the Acoustical Society of Korea
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    • v.23 no.5
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    • pp.400-409
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    • 2004
  • In this paper. a voice personality transformation method is proposed. which makes one person's voice sound like another person's voice. To transform the voice personality. vocal tract transfer function is used as a transformation parameter. Comparing with previous methods. the proposed method makes transformed speech closer to target speaker's voice in both subjective and objective points of view. Conversion between vocal tract transfer functions is implemented by classification of entire vector space followed by linear transformation for each cluster. LPC cepstrum is used as a feature parameter. A joint classification and transformation method is proposed, where optimum clusters and transformation matrices are simultaneously estimated in the sense of a minimum mean square error criterion. To evaluate the performance of the proposed method. transformation rules are generated from 150 sentences uttered by three male and on female speakers. These rules are then applied to another 150 sentences uttered by the same speakers. and objective evaluation and subjective listening tests are performed.

Analysis of Linear Consolidation Problems by the Boundary Element Method (경계요소법에 의한 선형 압밀문제의 해석)

  • 서일교
    • Computational Structural Engineering
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    • v.8 no.4
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    • pp.129-136
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    • 1995
  • This paper presents a boundary element method for obtaining approximate solutions of 2-dimensional consolidation problems based on the Biot's linear theory. Laplace transform is applied to differential equation system in order to eliminate the time dependency. The boundary integral equations in transformed space are formulated and the fundamental solutions are shown in a closed form. In order to convert the transformed solutions to the ones in real space, the Hosono's numerical Laplace transform inversion method is applied. As a numerical example, a half-space consolidation problem subjected to a strip local load is selected and the applicability of the method is demonstrated through the comparison with the exact solutions.

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Nonlinear Optimization Method for Multiple Image Registration (다수의 영상 특징점 정합을 위한 비선형 최적화 기법)

  • Ahn, Yang-Keun;Hong, Ji-Man
    • Journal of Broadcast Engineering
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    • v.17 no.4
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    • pp.634-639
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    • 2012
  • In this paper, we propose nonlinear optimization method for feature matching from multiple view image. Typical solution of feature matching is by solving linear equation. However this solution has large error due to nonlinearity of image formation model. If typical nonlinear optimization method is used, complexity grows exponentially over the number of features. To make complexity lower, we use sparse Levenberg-Marquardt nonlinear optimization for matching of features over multiple view image.

MDS code Creation Confirmation Algorithms in Permutation Layer of a Block Cipher (블록 암호에서 교환 계층의 MDS 코드 생성 확인 알고리즘)

  • 박창수;조경연
    • Journal of the Korea Institute of Information and Communication Engineering
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    • v.7 no.7
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    • pp.1462-1470
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    • 2003
  • According to the necessity about information security as well as the advance of IT system and the spread of the Internet, a variety of cryptography algorithms are being developed and put to practical use. In addition the technique about cryptography attack also is advanced, and the algorithms which are strong against its attack are being studied. If the linear transformation matrix in the block cipher algorithm such as Substitution Permutation Networks(SPN) produces the Maximum Distance Separable(MDS) code, it has strong characteristics against the differential attack and linear attack. In this paper, we propose a new algorithm which cm estimate that the linear transformation matrix produces the MDS code. The elements of input code of linear transformation matrix over GF$({2_n})$ can be interpreted as variables. One of variables is transformed as an algebraic formula with the other variables, with applying the formula to the matrix the variables are eliminated one by one. If the number of variables is 1 and the all of coefficient of variable is non zero, then the linear transformation matrix produces the MDS code. The proposed algorithm reduces the calculation time greatly by diminishing the number of multiply and reciprocal operation compared with the conventional algorithm which is designed to know whether the every square submatrix is nonsingular.

Geocoding of the Free Stereo Mosaic Image Generated from Video Sequences (비디오 프레임 영상으로부터 제작된 자유 입체 모자이크 영상의 실좌표 등록)

  • Noh, Myoung-Jong;Cho, Woo-Sug;Park, Jun-Ku;Kim, Jung-Sub;Koh, Jin-Woo
    • Journal of the Korean Society of Surveying, Geodesy, Photogrammetry and Cartography
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    • v.29 no.3
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    • pp.249-255
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    • 2011
  • The free-stereo mosaics image without GPS/INS and ground control data can be generated by using relative orientation parameters on the 3D model coordinate system. Its origin is located in one reference frame image. A 3D coordinate calculated by conjugate points on the free-stereo mosaic images is represented on the 3D model coordinate system. For determining 3D coordinate on the 3D absolute coordinate system utilizing conjugate points on the free-stereo mosaic images, transformation methodology is required for transforming 3D model coordinate into 3D absolute coordinate. Generally, the 3D similarity transformation is used for transforming each other 3D coordinates. Error of 3D model coordinates used in the free-stereo mosaic images is non-linearly increased according to distance from 3D model coordinate and origin point. For this reason, 3D model coordinates used in the free-stereo mosaic images are difficult to transform into 3D absolute coordinates by using linear transformation. Therefore, methodology for transforming nonlinear 3D model coordinate into 3D absolute coordinate is needed. Also methodology for resampling the free-stereo mosaic image to the geo-stereo mosaic image is needed for overlapping digital map on absolute coordinate and stereo mosaic images. In this paper, we propose a 3D non-linear transformation for converting 3D model coordinate in the free-stereo mosaic image to 3D absolute coordinate, and a 2D non-linear transformation based on 3D non-linear transformation converting the free-stereo mosaic image to the geo-stereo mosaic image.

The Interpreter Controllability and Observability for a Class of Time-varying Linear System via I/S and I/O Transformation (입력-상태, 입력-출력 변환을 이용한 선형 시변 시스템의 가제어성, 가관측성 해석)

  • Won, Young-Jin;Lee, Sang-Hun;Lee, Jong-Yong
    • 전자공학회논문지 IE
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    • v.44 no.3
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    • pp.51-55
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    • 2007
  • In this paper, we consider the controllability and observability for the time-varying linear system using the input-state(I/O), input-output(I/O) transformation and get the time-invarying linear system. The transformed system represent the system with the multiple integral. We verify the proposal algorithm via the example and examine.

Decreasing of Correlations Among Hidden Neurons of Multilayer Perceptrons (비선형 변환에 의한 중간층 뉴런 상관계수 감소)

  • 오상훈
    • The Journal of the Korea Contents Association
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    • v.3 no.3
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    • pp.98-102
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    • 2003
  • For elucidating the key role of hidden neurons in information processing of Multilayer perceptrons(MLPs), we prove that the correlation coefficient between weighted sums to hidden neurons decreases under element-wise nonlinear transformations. This is verified through training of MLPs for an isolated word recognition problem. From this result, we can say that the element-wise nonlinear functions reduces redundancy in the information contents of hidden neurons.

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