• Title/Summary/Keyword: ESSENTIAL ELEMENT

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Programmed Cell death in plants

  • Fukuda, Hiroo
    • Proceedings of the Botanical Society of Korea Conference
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    • 1999.07a
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    • pp.69-73
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    • 1999
  • In plants as well as in other multicellular organisms, programmed cell death plays essential roles in the abortion or formation of specific cells and tissues during development to organize the plant [11, 15, 18]. A typical example of developmentally programmed cell death in plants is the death during differentiation of tracheary elements which are components of vessels and tracheids, a water-conducting system. The programming of cell death during tracheary element differentiation has been revealed to be unique to plant cells by using the in vitro Zinnia mesophyll cell culture system. In particular, new biosynthesis of autolysis-related enzymes such as cysteine proteases and nucleases, their accumulation of the vacuole and the programmed collapse of the vacuole are essential to the death of tracheary elements and differ greatly from the process of the apoptotic cell death in animals.

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Review for Selenium-fortified Functional Products of Livestock (셀레늄 강화 기능성 축산물에 관한 고찰)

  • Kim, W.Y.
    • Journal of Practical Agriculture & Fisheries Research
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    • v.5 no.1
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    • pp.36-56
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    • 2003
  • Selenium(Se) is an essential trace element in the human body. Main function of this element is a catalytic part of antioxidant enzymes that protect cells against the attacks of free radicals that are produced during normal metabolism of the body. Se is also essential for normal function of the immune system and thyroid gland. It also appears to be a key nutrient in counteracting the development of virulence and inhibiting HIV(human immunodeficiency virus) progression to AIDS. It is also required for sperm motility and reduces the depression. Therefore, it is very meaningful that livestock producers generate Se-fortified animal products, such as Se-egg, Se-milk, Se-pork, Se-chicken and Se-beef from the point of producers as well as human heath. However, regulation on Se usage and Se-fortified food/feed is far from being clear in Korea even though Se should be carefully monitored because of its toxicity. Thus, one has to be aware of Se properties when designing Se-fortified animal products.

Characteristics of Patterns on Art-Walls as an Imagery Element in Contemporary Living Spaces (국내 공동주거 공간 이미지 요소로서의 아트월 패턴 연구)

  • Park, Young-Soon;Kim, Seong-Ah;Kim, Eun-Jung;Lim, Sun-Hee
    • Korean Institute of Interior Design Journal
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    • v.19 no.3
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    • pp.86-94
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    • 2010
  • Art-Wall is the term for a surface wall representing artistic expression by using different materials or images in interior spaces. Usually this is the focal point in an interior space and sometimes it called as an image wall. In the new millenium Art-walls began to use in living spaces. While in the early stages of the development, Art-Wall was limited in a living room, in contemporary it spread into overall living spaces using various patterns and materials. Therefore, the research on Art-Walls in contemporary living spaces is essential to understand this development. The purpose of this study is to find out characteristics of patterns on Art-Walls as an imagery element in contemporary interior spaces. To analyze the characteristic, the analysis table for Art-Walls are constructed based on classifications of wallpapers and textiles. Based on this analysis table, 89 examples of Art-Walls from four major periodicals from 2008 to 2009 were examined. As a result of the analysis, in contemporary interior spaces solid-texture pattern is most frequently appeared. Then natural motifs are the next most popular using oversized or irregular layouts. The result shows that naturalistic expression is significant in interior space in 2008 to 2009. Therefore, Art-Walls that adapted diverse patterns are an essential element in contemporary interiors to represent the major concept of the space.

Local A Posteriori Error Estimates for Obstacle Contact Problems (장애물 접촉문제에서의 지역 A Posteriori 오차계산)

  • 이춘열
    • Journal of the Korean Society for Precision Engineering
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    • v.15 no.5
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    • pp.120-127
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    • 1998
  • Differential inequalities occurring in problems of obstacle contact problems are recast into variational inequalities and analyzed by finite element methods. A new a posteriori error estimator, which is essential in adaptive finite element method, is introduced to capture the errors in finite element approximations of these variational inequalities. In order to construct a posteriori error estimates, saddle point problems are introduced using Lagrange parameters and upper bounds are provided. The global upper bound is localized by a special mixed formulation, which leads to upper bounds of the element errors. A numerical experiment is performed on an obstacle contact problem to check the effectivity index both in a local and a global sense.

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Trace Element Deficiency in Children Receiving Total Parenteral Nutrition (TPN) (총정맥영양(TPN)과 관련된 미량원소의 결핍)

  • Lee, Jung Hwa
    • Pediatric Gastroenterology, Hepatology & Nutrition
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    • v.11 no.sup1
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    • pp.117-126
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    • 2008
  • Trace elements compose a very small portion of the body, however they have a variety of essential functions. Various diseases are caused by trace element deficiencies, and sometimes they can be fatal. Long-term TPN is a risk factor of trace element deficiency, and trace elements need to be checked regularly while receiving TPN. It is important to provide sufficient requirements of trace elements regarding the clinical features and the problems of trace element excess or deficiency. Moreover extensive studies to establish the efficiency of examining human hair and nails, recent method to determine the trace elements, are required.

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Rotation-Free Plate Element Based on the Natural Element Method (자연요소법에 기초한 회전자유도가 없는 평판요소)

  • Cho, Jin-Rae;Choi, Joo-Hyoung;Lee, Hong-Woo
    • Proceedings of the Computational Structural Engineering Institute Conference
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    • 2007.04a
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    • pp.513-518
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    • 2007
  • A polygon-wise constant curvature natural element approximation is presented in this paper for the numerical implementation of the abstract Kirchhoff plate model. The strict continuity requirement in the displacement field is relaxed by converting the area integral of the curvatures into the boundary integral along the Voronoi boundary. Curvatures and bending moments are assumed to be constant within each Voronoi polygon, and the Voronoi-polygon-wise constant curvatures are derived in a selective manner for the sake of the imposition of essential boundary conditions. The numerical results illustrating the proposed method are also given.

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A new finite element based on the strain approach with transverse shear effect

  • Himeur, Mohammed;Benmarce, Abdelaziz;Guenfoud, Mohamed
    • Structural Engineering and Mechanics
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    • v.49 no.6
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    • pp.793-810
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    • 2014
  • This research work deals with the development of a new Triangular finite element for the linear analysis of plate bending with transverse shear effect. It is developed in perspective to building shell elements. The displacements field of the element has been developed by the use of the strain-based approach and it is based on the assumed independent functions for the various components of strain insofar as it is allowed by the compatibility equations. Its formulation uses also concepts related to the fourth fictitious node, the static condensation and analytic integration. It is based on the assumptions of tick plate.s theory (Reissner-Mindlin theory). The element possesses three essential external degrees of freedom at each of the four nodes and satisfies the exact representation of the rigid body modes of displacements. As a result of this approach, a new bending plate finite element (Pep43) which is competitive, robust and efficient.

Improved Element-Free Galerkin method (IEFG) for solving three-dimensional elasticity problems

  • Zhang, Zan;Liew, K.M.
    • Interaction and multiscale mechanics
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    • v.3 no.2
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    • pp.123-143
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    • 2010
  • The essential idea of the element-free Galerkin method (EFG) is that moving least-squares (MLS) approximation are used for the trial and test functions with the variational principle (weak form). By using the weighted orthogonal basis function to construct the MLS interpolants, we derive the formulae for an improved element-free Galerkin (IEFG) method for solving three-dimensional problems in linear elasticity. There are fewer coefficients in improved moving least-squares (IMLS) approximation than in MLS approximation. Also fewer nodes are selected in the entire domain with the IEFG method than is the case with the conventional EFG method. In this paper, we selected a few example problems to demonstrate the applicability of the method.

Precision Current Measurement of Magnet Power Supply at the PLS-II (포항가속기연구소 전자석전원장치 출력 전류 정밀 측정)

  • Kim, Sung-chul;An, Suk-Ho
    • Proceedings of the KIPE Conference
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    • 2016.07a
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    • pp.67-68
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    • 2016
  • The accurate measurement of magnet power supplies (MPS) output currents is essential to delivering stable and repeatable currents to magnets in particle accelerators. An essential element in guaranteeing and evaluating the required performance is the current measurement device and methode. In this paper, we discuss instrument and methods for precision current measurement and performance of the PLS-II MPS.

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