• Title/Summary/Keyword: Modification Function

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Enigma of Small Peptides Ubiquitin and SUMO in Plants

  • Seo, Hak Soo
    • Korean Journal of Breeding Science
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    • v.42 no.4
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    • pp.339-343
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    • 2010
  • Post-translational covalent modifications by small molecules or peptides remodel target proteins. One such modification, made by ubiquitin or small ubiquitin-related modifier (SUMO), is a rapidly expanding field in cell signaling pathways. Ubiquitin attachment controls the turnover and degradation of target proteins while SUMO conjugation regulates their activity and function. Recent studies report many examples of cross-talk between ubiquitin and SUMO pathways, indicating that the boundary is no longer clear. Here, we review recent progress concerning how ubiquitin and SUMO participate in new regulatory roles in plant cell, and how ubiquitination and sumoylation control plant growth and development.

XML Data support in RDBMS through XML-View (관계형 데이타베이스 시스템에서 XML-뷰를 통한 XML 데이타의 지원)

  • Lee, Je-Min;Min, Kyung-Sub;Park, Sang-Won;Kim, Hyong-Joo
    • Journal of KIISE:Computing Practices and Letters
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    • v.7 no.3
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    • pp.202-210
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    • 2001
  • Recently, XML is emerging as a web document standard and researches on storing and querying XML documents using existing RDBMS are actively in progress. In this paper, we propose a method that enables users to view and use XML documents like a relational table by extending concept of RDBMS's SQL view and. table function. In our approach, XML documents are existed independently of RDBMS and users can register relational schema of necessary part of XML document by using XML-View definition statement. Registered XML-View can be queried by SQL, and XML -table function is internally used so that XML - View can be accessed and used like a relational table. The proposed method enables users to access XML documents by providing the XML- View definition syntax and the table-function for existing RDBMS. Also, when schema modification for XML is needed, user can handle by modification of the XML- View definition.

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A Study on the Improvement of FEM model in Plate Vibration by Modification of Young's Modulus and Shape (FEM 모델의 형상과 감쇠계수의 추정을 통한 평판진동해석의 개선에 대한 연구)

  • Park, Sok-Chu;Oh, Chang-Guen
    • Journal of Advanced Marine Engineering and Technology
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    • v.36 no.6
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    • pp.794-801
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    • 2012
  • Finite Element Method is a strong tool to analyse static and dynamic problem of a structure. FEM is a good method for static problem, but for dynamic problem there are some differences between real phenomena and analyzed phenomena. Therefore some modifications are needed to identify two results. In this paper authors propose a genetic algorithm method 1) to adjust dimensions of plate for identifying natural frequencies, 2) to fit amplitude of FEM Frequency Response Function(FRF) onto it of real FRF. Analysis by raw FEM data gave questions if the results were for the same object. By only adjusting Young's modulus much better accordances were obtained, but limitation existed still. Very good agreements were achieved by shape modification and damping coefficient identification.

A Method of Deriving an Intensity Mapping Function by Using The Variational Technique (변분법을 이용한 명암도 변환 함수 획득 방법)

  • Kim, Jun-Hyung;Noh, Chang-Kyun;Ko, Sung-Jea
    • Journal of the Institute of Electronics Engineers of Korea SP
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    • v.48 no.5
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    • pp.10-15
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    • 2011
  • Histogram equalization is an effective method to enhance the contrast of the image. However, it can result in unwanted artifacts such as excessive contrast enhancement and noise amplification. These artifacts can be reduced by modifying an intensity mapping function which is generated by histogram equalization. In this paper, we present a variational approach to the modification of the intensity mapping function. We define a functional whose minimization produces a modified intensity mapping function. Experimental results show that the intensity mapping function obtained by the proposed method can enhance the contrast of the image without visual artifacts.

An Improved Mesh-free Crack Analysis Technique Using a Singular Basis Function (특이기저함수를 이용하여 개선한 Mesh-free 균열해석기법)

  • 이상호;윤영철
    • Journal of the Computational Structural Engineering Institute of Korea
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    • v.14 no.3
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    • pp.381-390
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    • 2001
  • In this paper, a new improved crack analysis technique by Element-Free Galerkin(EFG) method is proposed, in which the singularity and the discontinuity of the crack successfully described by adding enrichment terms containing a singular basis function to the standard EFG approximation and a discontinuity function implemented in constructing the shape function across the crack surface. The standard EFG method requires considerable addition of nodes or modification of the model. In addition, the proposed method significantly decreases the size of system of equation compared to the previous enriched EFG method by using localized enrichment region near the crack tip. Numerical example show the improvement and th effectiveness of the previous method.

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Calculation of Stress Intensity Factors Using Single-Layer Potential and Weight Function (Single-Layer 포텐셜과 가중함수를 이용한 응력강도계수의 계산)

  • 이형연;홍창선
    • Transactions of the Korean Society of Mechanical Engineers
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    • v.19 no.4
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    • pp.981-989
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    • 1995
  • A new weight function approach to determine SIF(stress intensity factor) using single-layer potential has been presented. The crack surface displacement field was represented by one boundary integral term whose kernel was modified from Kelvin's fundamental solution. The proposed method enables the calculation of SIF using only one SIF solution without any modification for the crack geometries symmetric in two-dimensional plane such as a center crack in a plate with or without an internal hole, double edge cracks, circumferential crack or radial cracks in a pipe. The application procedure to those crack problems is very simple and straightforward with only one SIF solution. The necessary information in the analysis is two reference SIFs. The analysis results using present closed-form solution were in good agreement with those of the literature.

Sequential Shape Modification for Monotone Convex Function: L2 Monotonization and Uniform Convexifiation

  • Lim, Jo-Han;Lee, Sung-Im
    • Communications for Statistical Applications and Methods
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    • v.15 no.5
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    • pp.675-685
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    • 2008
  • This paper studies two sequential procedures to estimate a monotone convex function using $L_2$ monotonization and uniform convexification; one, denoted by FMSC, monotonizes the data first and then, convexifis the monotone estimate; the other, denoted by FCSM, first convexifies the data and then monotonizes the convex estimate. We show that two shape modifiers are not commutable and so does FMSC and FCSM. We compare them numerically in uniform error(UE) and integrated mean squared error(IMSE). The results show that FMSC has smaller uniform error(UE) and integrated mean squared error(IMSE) than those of FCSC.

A Bayesian Inference for Power Law Process with a Single Change Point

  • Kim, Kiwoong;Inkwon Yeo;Sinsup Cho;Kim, Jae-Joo
    • International Journal of Quality Innovation
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    • v.5 no.1
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    • pp.1-9
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    • 2004
  • The nonhomogeneous poisson process (NHPP) is often used to model repairable systems that are subject to a minimal repair strategy, with negligible repair times. In this situation, the system can be characterized by its intensity function. There have been many NHPP models according to intensity functions. However, the intensity function of system in use can be changed because of repair or its aging. We consider the single change point model as the modification of the power law process. The shape parameter of its intensity function is changed before and after the change point. We detect the presence of the change point using Bayesian methodology. Some numerical results are also presented.

A V-Shaped Lyapunov Function Approach to Model-Based Control of Flexible-Joint Robots

  • Lee, Ho-Hoon;Park, Seung-Gap
    • Journal of Mechanical Science and Technology
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    • v.14 no.11
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    • pp.1225-1231
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    • 2000
  • This paper proposes a V-shaped Lyapunov function approach for the model-based control of flexible-joint robots, in which a new model-based nonlinear control scheme is designed based on a V-shaped Lyapunov function. The proposed control guarantees global asymptotic stability for link trajectory control while keeping all internal signals bounded. Since joint flexibility is used as a control parameter, the proposed control is not restricted by the degree of joint flexibility and be applied to flexibility-joint, partly-flexibility, or rigid-joint robots without modification. the effectiveness of the proposed control has been by computer simulation.

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An analysis and modification of a unified phase 1-phase 2 semi-infinite constrained optimization algorithm

  • Yang, Hyun-Suk
    • 제어로봇시스템학회:학술대회논문집
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    • 1994.10a
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    • pp.483-487
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    • 1994
  • In this paper, we analize the effect of a steering water used in a unified phase I-phase II semi-infinite constrained optimization algorithm and present a new algorithm based on the facts that when the point x is far away from the feasible region where all the constraints are satisfied, reaching to the feasible region is more important than minimizing the cost function and that when the point x is near the region, it is more efficient to try to reach the feasible region and to minimize the cost function concurrently. Also, the angle between the search direction vector and the gradient of the cost function is considered when the steering parameter value is computed. Even though changing the steering parameter does not change the rate of convergence of the algorithm, we show through some examples that the proposed algorithm performs better than the other algorithms.

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