• Title/Summary/Keyword: Structure determination

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Dynamic Characteristics and Compressive Stress of Multi-Layered Structure (적층 구조물의 압축응력과 동적특성)

  • Shon, Ho-Woong;Lee, Sung-Min
    • Journal of the Korean Geophysical Society
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    • v.9 no.1
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    • pp.63-71
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    • 2006
  • When surveying the cultural heritages especially in the case of stone structures, preserving their originalstate is of primary importance. For the effective assessment of survey results of stone structure, thedynamic characteristics of that system should be considered. Dynamic characteristics of stone masonry structures depend on several factors such as coefficients of friction, contact conditions, and number of layers of bonding stones. These factors can be estimated by using the dynamic analysis results. This paper describes a method for natural frequency determination of traditional stone arch bridge subjected to compressive force. For this purpose, multi-layered granite brick models of for arch bridge were made and fundamental frequencies corresponding increasing axial forces were measured.

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On The Mathematical Structure of Markov Process and Markovian Sequential Decision Process (Markov 과정(過程)의 수리적(數理的) 구조(構造)와 그 축차결정과정(逐次決定過程))

  • Kim, Yu-Song
    • Journal of Korean Society for Quality Management
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    • v.11 no.2
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    • pp.2-9
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    • 1983
  • As will be seen, this paper is tries that the research on the mathematical structure of Markov process and Markovian sequential decision process (the policy improvement iteration method,) moreover, that it analyze the logic and the characteristic of behavior of mathematical model of Markov process. Therefore firstly, it classify, on research of mathematical structure of Markov process, the forward equation and backward equation of Chapman-kolmogorov equation and of kolmogorov differential equation, and then have survey on logic of equation systems or on the question of uniqueness and existence of solution of the equation. Secondly, it classify, at the Markovian sequential decision process, the case of discrete time parameter and the continuous time parameter, and then it explore the logic system of characteristic of the behavior, the value determination operation and the policy improvement routine.

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Reactivity of Functional Food Substance in terms of Structure Analysis

  • Kwon, Dae-Young
    • Proceedings of the Korean Society of Food Hygiene and Safety Conference
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    • 2003.11a
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    • pp.46-46
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    • 2003
  • Hypocholesterolemic peptide isolated from glycimin (11S protein) hydrolyzate by trypsin was purified and identified as LPYP and IAVPGEVA. To investigate the effects of phyiscal properties of side chains of the hypocholesterolemic activity, some of mutant peptides were designed and synthesized chemically. The structure related structures of each peptide were simulated and constructed and their conformations were observed by using spectropolarimeter. The hypocholesterolemic activities were monitored by assaying the inhibition of 3-hydroxy-3-methylglutaryl CoA reductase (HMG-CoA reductase) in vitro and by the determination of cholesterol content in mice serum. For LPYP derivatives, Hypocholesterolemic activity was lost when hydrophobic leucine residue at N-terminus was not so critical for maintaining hypocholesterolemic activity. For idealogical design of hypocholesterolemic peptides, the structure of HMG-CoA reductase are shown and inhibition mechanism of some peptides or inhibitors will be presented. For IAVPGEVA derivative inhibition of HMG-CoA reductase has been studied. For detail study of hypocholesterolemic activity, kinetic study of inhibition of peptides on HMG-CoA reductase and structural view of ligand binding should be investigated.

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The Structure Determination of a Herbicidal Compound, 3D5

  • Kim, Shin-Duk;Ryoo, In-Ja;Kim, Chang-Jin;Uramoto, Masakazu;Yoo, Ick-Dong
    • Journal of Microbiology and Biotechnology
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    • v.3 no.1
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    • pp.51-56
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    • 1993
  • The structure of herbicidal compound, 3D5, isolated from the culture broth of Streptomyces sp. 3D5, was elucidated as a 16-membered diene macrolide by the spectroscopic method. It was identical with bafilomycin D which has been known to be an insecticidal compound and an inhibitor of $K^{+}-dependent$ ATPase. However, this is the first report which shows that bafilomycin D has a herbicidal activity.

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An Empirical Investigation of Agency Costs in the Determination of Performance of Pakistani Nonfinancial Sector

  • Siddiqui, Muhammad Ayub;Afzal, Usman
    • Journal of Distribution Science
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    • v.10 no.5
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    • pp.19-28
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    • 2012
  • The study examines the performance and its relationship with capital structure and agency cost with respect to the industrial configurations and economic groups of Pakistan Economy. The study employs data set of 334 listed joint stock companies from the nonfinancial sectors for the period of 1999-2009 from cotton and textile, engineering, chemical, sugar, cement, fuel and energy, paper and board, transport and communication, and miscellaneous economic groups. Pooled data from the Panel data methodology has been applied to observe the significance of different performance measures through determinant of capital structure and agency costs with special focus on the leverage and cash flows as the direct determinant and interactive variables. The empirical test results using redundant variable tests demonstrate support for agency theory in the context of Pakistan's industrial configurations. The implications of the study point towards more investigations on the subject using industrial configurations as control and moderating variables.

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KPACK: Relativistic Two-component Ab Initio Electronic Structure Program Package

  • Kim, Inkoo;Lee, Yoon Sup
    • Bulletin of the Korean Chemical Society
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    • v.34 no.1
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    • pp.179-187
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    • 2013
  • We describe newly developed software named KPACK for relativistic electronic structure computation of molecules containing heavy elements that enables the two-component ab initio calculations in Kramers restricted and unrestricted formalisms in the framework of the relativistic effective core potential (RECP). The spin-orbit coupling as relativistic effect enters into the calculation at the Hartree-Fock (HF) stage and hence, is treated in a variational manner to generate two-component molecular spinors as one-electron wavefunctions for use in the correlated methods. As correlated methods, KPACK currently provides the two-component second-order M${\o}$ller-Plesset perturbation theory (MP2), configuration interaction (CI) and complete-active-space self-consistent field (CASSCF) methods. Test calculations were performed for the ground states of group-14 elements, for which the spin-orbit coupling greatly influences the determination of term symbols. A categorization of three procedures is suggested for the two-component methods on the basis of spin-orbit coupling manifested in the HF level.

Development of the Micro PM type Stepping Motor with Newly Structure (새로운 구조를 갖는 마이크로 PM형 스테핑 모터 개발)

  • Rhyu, Se-Hyun;Kwon, Byung-Il;Jung, In-Soung;Sung, Ha-Gyeong
    • Proceedings of the KIEE Conference
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    • 2005.07b
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    • pp.1261-1263
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    • 2005
  • The micro permanent magnet(PM) type stewing motor preferred solution for many small electronics position determination devices since it is small in size. Thus, there are growing demands for PM type stepping motor that greater mechanical output, smaller size. But, the design of the it, having high performance and small size is very difficult because of its complex mechanical structure. This paper deals with a development of the newly structured micro PM type stepping motor with claw-poles. We introduced the small-sized PM type stepping motor that has new structure and analyzed the magnetic characteristic of it versus general type model using 3-D finite element analysis(FEA).

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Grain Size Determination of Copper Film by Electron Backscatter Diffraction (EBSD를 이용한 구리박막의 결정립 크기 결정)

  • Kim, Su-Hyeon;Kang, Joo-Hee;Han, Seung Zeon
    • Korean Journal of Metals and Materials
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    • v.48 no.9
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    • pp.847-855
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    • 2010
  • The grain size of a cross-section of $8{\mu}m$-thick copper film was determined by electron backscatter diffraction analysis. Grain size distribution histogram showed the presence of a large fraction of small-sized grains, and the mean grain size was significantly affected by handling of them. A cut-off grain size, below which all grains are ignored as noise and eliminated for the calculation of the mean value, should be three or four times as large as the step size. Due to the presence of small grains, the linear intercept method derived larger mean grain size, which depends less sensitively on the cut-off grain size than the equivalent circle diameter method.

Single Crystal EPR Spectra of $K_{12}[As_2W_18O_{66}Cu_3(H_2O)_2]{\cdot}11H_2O$, a Copper(II) Trimer

  • Jo, Yeong Hwan;So, Hyeon Su
    • Bulletin of the Korean Chemical Society
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    • v.16 no.3
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    • pp.243-248
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    • 1995
  • Single crystal EPR spectra of K12[As2W18O66Cu3(H2O)2]${\cdot}$11H2O exhibit an orientation-dependent fine structure of an S = 3/2 system which is accounted for by the exchange and magnetic dipole interactions among the three Cu2+ ions. The hyperfine structure and the lines from the S = 1/2 manifolds have not been observed. The isotropic exchange parameters determined from the magnetic susceptibility data at 5-300 K are J1 = J2 =-7.8 cm-1. The magnitude of J values suggests that the unpaired electrons on three Cu2+ ions interact through a sequence of six bonds involving two tungsten atoms and three oxygen atoms. The Cu-Cu distance, 4.37 $\AA$, determined from the EPR spectra is considerably smaller than the value from the X-ray crystal structure determination, 4.76 $\pm$ 0.03 $\AA$, indicating that the point-dipole model underestimates the dipolar interaction.

Understanding the Structure-Property Relationship in Functional Materials Using 3D Atom Probe Tomography (3차원 원자단층현미경을 활용한 기능성 재료의 구조-특성 관계 해석)

  • Chanwon Jung
    • Journal of the Korean Institute of Electrical and Electronic Material Engineers
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    • v.37 no.5
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    • pp.476-485
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    • 2024
  • Understanding the structure-property relationship in functional materials is crucial as microstructural features such as nano-precipitates, phase boundary, grain boundary segregation, and grain boundary phases play a key role in their functional properties. Atom probe tomography (APT) is an advanced analytical technique that allows for the three-dimensional (3D) mapping of atomic distributions and the precise determination of local chemical compositions in materials. Moreover, it offers sub-nanometer spatial resolution and chemical sensitivity at the tens of parts per million (ppm) level. Owing to its unique capabilities, this technique has been employed to uncover the 3D elemental distributions in a wide range of materials, including alloys, semiconductors, nanomaterials, and even biomaterials. In this paper, various kinds of examples are introduced for elucidating structure-property relationships on functional materials by utilizing the atom probe tomography.