• Title/Summary/Keyword: convergence domain

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A Digital Hologram Encryption Method Using Data Scrambling of Frequency Coefficients

  • Choi, Hyun-Jun
    • Journal of information and communication convergence engineering
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    • v.11 no.3
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    • pp.185-189
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    • 2013
  • A digital hologram generated by a computer calculation (computer-generated hologram or capture using charge-coupled device [CCD] camera) is one of the most expensive types of content, and its usage is expanding. Thus, it is highly necessary to protect the ownership of digital holograms. This paper presents an efficient visual security scheme for holographic image reconstruction with a low scrambling cost. Most recent studies on optical security concentrate their focus on security authentication using optical characteristics. However, in this paper, we propose an efficient scrambling method to protect a digital hologram. Therefore, we introduce in this paper several scrambling attempts in both the spatial domain and frequency domain on the basis of the results of analyzing the properties of the coefficients in each domain. To effectively hide the image information, 1/4, 1/256, and 1/16,384 of the original digital hologram needs to be scrambled for the spatial-domain scheme, Fresnel-domain scheme, and discrete cosine transform-domain scheme, respectively. The encryption schemes and the analyses in this paper can be expected to be useful in the research on encryption and other works on digital holograms.

Molecular interaction between SH3 domain of PACSIN2 and proline-rich motifs of Cobll1

  • Yoo, Hee-Seop;Seok, Seung-Hyeon;Kim, Ha-Neul;Kim, Ji-Hun;Seo, Min-Duk
    • Journal of the Korean Magnetic Resonance Society
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    • v.26 no.3
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    • pp.34-39
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    • 2022
  • The SH3 domain found within a variety of proteins is comprised of generally 60 residues, and participated in protein-protein interactions with proline-rich motifs. Cobll1 was identified as a distinct molecular marker associated with CML progression, and PACSIN2 was discovered a novel Cobll1 binding partner through direct interaction between a SH3 domain of PACSIN2 and three proline-rich motifs of Cobll1. To understand the structural basis of interactions between PACSIN2 and Cobll1, backbone assignments of PACSIN2 SH3 domain were performed. Furthermore, three proline-rich peptides of Cobll1 were titrated to 15N-labeled PACSIN2 SH3 domain in various ratios. Our chemical shift changes data and conserved SH3 sequence alignment will be helpful to analyze fundamental molecular basis related to the interaction between PACSIN2 and Cobll1.

A Multi-domain Style Transfer by Modified Generator of GAN

  • Lee, Geum-Boon
    • Journal of the Korea Society of Computer and Information
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    • v.27 no.7
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    • pp.27-33
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    • 2022
  • In this paper, we propose a novel generator architecture for multi-domain style transfer method not an image to image translation, as a method of generating a styled image by transfering a style to the content image. A latent vector and Gaussian noises are added to the generator of GAN so that a high quality image is generated while considering the characteristics of various data distributions for each domain and preserving the features of the content data. With the generator architecture of the proposed GAN, networks are configured and presented so that the content image can learn the styles for each domain well, and it is applied to the domain composed of images of the four seasons to show the high resolution style transfer results.

Robust tuning of quadratic criterion-based iterative learning control for linear batch system

  • Kim, Won-Cheol;Lee, Kwang-Soon
    • 제어로봇시스템학회:학술대회논문집
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    • 1996.10a
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    • pp.303-306
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    • 1996
  • We propose a robust tuning method of the quadratic criterion based iterative learning control(Q-ILC) algorithm for discrete-time linear batch system. First, we establish the frequency domain representation for batch systems. Next, a robust convergence condition is derived in the frequency domain. Based on this condition, we propose to optimize the weighting matrices such that the upper bound of the robustness measure is minimized. Through numerical simulation, it is shown that the designed learning filter restores robustness under significant model uncertainty.

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Iterative learning control based on inverse process model

  • Lee, Kwang-Soon
    • 제어로봇시스템학회:학술대회논문집
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    • 1992.10b
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    • pp.539-544
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    • 1992
  • An iterative lear-rung control scheme is newly designed in tile frequency domain. Purposing for batch process control, a generic form of feedback-assisted first-order learning is considered first, and the inverse model-based learning algorithm is derived through convergence analysis in the frequency domain. To enhance the robustness of the proposed scheme, a filtered version is also presented. Performance of the proposed scheme is evaluated through numerical simulations.

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Control of a batch reactor by learning operation

  • Lee, Kwang-Soon;Cho, Moon-Khi;Cho, Jin-Won
    • 제어로봇시스템학회:학술대회논문집
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    • 1990.10b
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    • pp.1277-1283
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    • 1990
  • The iterative learning control synthesized in the frequency domain has been utilized for temperature control of a batch reactor. For this purpose, a feedback-assisted generalized learning control scheme was constructed first, and the convergence and robustness analyses were conducted in the frequency domain. The feedback-assisted learning operation was then implemented in a bench scale batch reactor where reaction heat is simulated using an electric heater. As a result, progressive reduction of temperature control error could be obviously observed as batch operation is repeated.

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A DOMAIN DECOMPOSITION PRECONDITIONER FOR STEADY GROUNDWATER FLOW IN POROUS MEDIA

  • Ghahreman, N.;Kerayechian, A.
    • Journal of applied mathematics & informatics
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    • v.7 no.3
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    • pp.773-785
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    • 2000
  • In this paper an algorithm is presented based on the additive Schwarz method for steady groundwater flow in a porous medium. The subproblems in the algorithm correspond to the problem on a coarse grid and some overlapping subdomains. It will be shown that the rate of convergence is independent of the mesh parameters and discontinuities of the coefficients, and depends on the overlap ratio.

A Frequency-Domain Normalized MBD Algorithm with Unidirectional Filters for Blind Speech Separation

  • Kim Hye-Jin;Nam Seung-Hyon
    • The Journal of the Acoustical Society of Korea
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    • v.24 no.2E
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    • pp.54-60
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    • 2005
  • A new multichannel blind deconvolution algorithm is proposed for speech mixtures. It employs unidirectional filters and normalization of gradient terms in the frequency domain. The proposed algorithm is shown to be approximately nonholonomic. Thus it provides improved convergence and separation performances without whitening effect for nonstationary sources such as speech and audio signals. Simulations using real world recordings confirm superior performances over existing algorithms and its usefulness for real applications.

fast running FIR filter structure based on Wavelet adaptive algorithm for computational complexity (웨이블렛 기반 적응 알고리즘의 계산량 감소에 적합한 Fast running FIR filter에 관한 연구)

  • Lee, Jae-Kyun;Lee, Chae-Wook
    • Proceedings of the Korea Institute of Convergence Signal Processing
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    • 2005.11a
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    • pp.250-255
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    • 2005
  • In this paper, we propose a new fast running FIR filter structure that improves the convergence speed of adaptive signal processing and reduces the computational complexity. The proposed filter is applied to wavelet based adaptive algorithm. Actually we compared the performance of the proposed algorithm with other algorithm using computer simulation of adaptive noise canceler based on synthesis speech. As the result, the frequency domain algorithm is prefer than the existent time domain. we analyzed the Wavelet algorithm, short-length fast running FIR algorithm, fast-short-length fast running FIR algorithm and proposed algorithm.

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