• Title/Summary/Keyword: transition elements

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Investigation of bond-slip modeling methods used in FE analysis of RC members

  • Demir, Serhat;Husem, Metin
    • Structural Engineering and Mechanics
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    • v.56 no.2
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    • pp.275-291
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    • 2015
  • Adherence between reinforcement and the surrounding concrete is usually ignored in finite element analysis (FEA) of reinforced concrete (RC) members. However, load transition between the reinforcement and surrounding concrete effects RC members' behavior a great deal. In this study, the effects of bond-slip on the FEA of RC members are examined. In the analyses, three types of bond-slip modeling methods (perfect bond, contact elements and spring elements) and three types of reinforcement modeling methods (smeared, one dimensional line and three dimensional solid elements) were used. Bond-slip behavior between the reinforcement and surrounding concrete was simulated with cohesive zone materials (CZM) for the first time. The bond-slip relationship was identified experimentally using a beam bending test as suggested by RILEM. The results obtained from FEA were compared with the results of four RC beams that were tested experimentally. Results showed that, in FE analyses, because of the perfect bond occurrence between the reinforcement and surrounding concrete, unrealistic strains occurred in the longitudinal reinforcement. This situation greatly affected the load deflection relationship because the longitudinal reinforcements dominated the failure mode. In addition to the spring elements, the combination of a bonded contact option with CZM also gave closer results to the experimental models. However, modeling of the bond-slip relationship with a contact element was quite difficult and time consuming. Therefore bond-slip modeling is more suitable with spring elements.

Some Problems of Reading Donguisusebowon (『동의수세보원(東醫壽世保元)』 해석의 몇 가지 문제들)

  • Choi, Dae-Woo
    • Journal of Sasang Constitutional Medicine
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    • v.25 no.3
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    • pp.135-144
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    • 2013
  • Objectives Two conflicting readings of "Donguisusebowon" so far have been presented that Sasang Constitutional Medicine inherited the traditional Five Elements theory and that it was a new perspective on its own right. The main purpose of this paper is to review the theoretical ground of Sasang Constitutional Medicine to see whether it has inherited the Traditional Korean Medicine, and show that it had been developed as an original view independent of the Five Elements theory. Methods To do this, I inquired into the theoretical background of Sasang Constitutional Medicine as well as its philosophical premises and its leading ideas. Results and Conclusions As a result, I have found that Sasang Constitutional Medicine is an original medical theory developed in empirical terms on its own right, divorced from the transcendental view of the Five Elements theory, while borrowing some concepts from I-Ching and Neo-Confucianism only for technical tools. In short, Sasang Constitutional Medicine may well be put as calling for a reappraisal of the Han-medical and Confucian accounts of human being, and a transition from speculative method based on the Five Elements theory to a verifiable empirical method. In this vein, my reading of Sasang Constitutional Medicine in empirical perspective may well be appraised as presenting a new way to further inquiries into the theoretical nature of it, and to getting itself across with Western medicine as well.

Synthesis of Multifunctional AN-co-(MMA/IA) Fibrous ion-exchanger by Hydrolysis and Adsorption Properties for Trace Transition Elements (가수분해에 의한 AN-co-(MMA(IA) 다관능성 섬유이온교환체의 합성 및 미랑 전이금속 흡착특성)

  • 황택성;이선아;황계순
    • Polymer(Korea)
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    • v.25 no.6
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    • pp.765-773
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    • 2001
  • In In order to remove harmful trace elements such as $Co^{2+}$, $Ni^{2+}$ , $Cr_2O_7\;^{2-}$ from water, we synthesized AN-co-(MMA/IA) according to various mole ratio of monomers and spun by wet-spinning. And multi-functional PAN ion exchangers were prepared by hydrolysis. We observed structure, degree of functionalization, ion exchange capacity, distribution coefficient and mechanical properties for ion exchanger. Anion exchange capacity decreased in 4.5 ~ 4.2 meq/g with increasing of IA content and cation exchange capacity increased in 1.8 ~ 2.2 meq/g. Tensile strength of the ion exchanger increased up to 0.008 mol% IA content and appeared maximum value by 216$kg/cm^2$Distribution coefficient for AN-co-(MMA/IA) ion exchanger appeared maximum value for Co(II), Ni(II) in pH 5-6 range and for Cr(III) in pH 3-4 range. And the adsorption capacity was in the order of Cr(III) > Co(II) > Ni(II) for multicomponent in continuous process.

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The Effect of Alloying Elements and Heat Treatment on the Uniform Corrosion of 440A Martensitic Stainless Steel(I) (440A 강의 균일부식에 미치는 합금원소와 열처리의 영향(I))

  • Kim, Y.C.;Kang, C.Y.;Jung, B.H.
    • Journal of Power System Engineering
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    • v.15 no.2
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    • pp.42-48
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    • 2011
  • 440A martensitic stainless steels which were modified with reduced carbon content(~0.5%) and addition of small amount of nickel, vanadium, tungsten and molybdenum were manufactured. Effects of alloying elements and tempering temperatures on the uniform corrosion in the solution of lN H2S04 were investigated through the electrochemical polarization test. When tempering temperature is constant, corrosion current density in active-passive transition point, Icorr, decreased a little with an increase of austenitizing temperature. In addition to this, when austenitizing temperature is constant, longer holding time showed a little lower Icorr and Ipass, passive current density. And when austenitized at $1050^{\circ}C$ and tempered in a range of $350{\sim}750^{\circ}C$, best anti-corrosion properties were obtained at $350^{\circ}C$ tempering temperature while worst at $450^{\circ}C$ or $550^{\circ}C$. The specimens tempered at below $450^{\circ}C$ and above $550^{\circ}C$, similar and good anti-corrosion characteristics were obtained regardless of alloying elements added, showing anti-corrosion characteristics are influenced more by tempering temperature than by alloying elements.

A Study on Zen Fashion in the Point of View of Culture Transition (문화(文化) 전이(轉移)(culture transition)의 시각(視覺)에서 본 젠(禪) 패션 연구(硏究))

  • Park, Hye-Won
    • Journal of Fashion Business
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    • v.4 no.1
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    • pp.73-85
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    • 2000
  • The purpose of this study is for considering about Zen fashion in the point of view of culture transition. Through this research, the Far-East including Korea will be confirmed as a center of fashion culture in 21st century. The contents are the meaning of culture transition in Post Modern period, the meaning of Zen and changing of fashion trend as the background of Zen Fashion, and the characteristics of Zen fashion design. The results are as follows: Anti-western movement or dismantlement of culture has been represented the limitation of western centered culture. So the interesting about East means the changing to east from west in ideas. To make new creation in fashion field, the comprehension about the western fashion which has been preceeded and new trials using the our tradition will be needed. Zen is a kind of Buddhism and the essence of it is to find myself and express individual experiences. The change of one's sens of value, new age movement and concerning of environment and ecology make more comfortable, simple and healthy elements in clothing. The fusion style is under a vogue in life style and Zen is the core of this trend. The characteristics of Zen fashion are flat dismantlement which has been know as a Japanese style, oriental minimalism and nature beauty of ecology. This characteristics are found not only the shape, color but the will of the behind. The pursing temperance and naturalism are represented the fashion culture transition from the West to Far-East. Therefore multi points of fashion research is very important and the identify about Korean fashion is required in lately for new fashion paradigm.

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Optical properties of Rare-Earth-Implanted GaN Epilayer (희토류 원소를 이온주입법으로 도핑한 GaN 박막의 광전이 특성)

  • Kim, Yong-Min
    • Journal of the Korean Vacuum Society
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    • v.16 no.3
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    • pp.210-214
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    • 2007
  • We have studied optical transitions of Gd-implanted GaN epilayers. Photoluminescence transition intensity at 590 nm at T=5 K diminishes and its center position moves to short avelength (blue shift) with increasing temperature up to 200 K. Above T=200 K, the transition intensity increases with increasing temperature while the center position remains the same. We believe that such anomalous optical transition behavior is due to the effect of rare-element in the semiconductor host material and lattice imperfection which was occurred during the implantation process well as.

COHERENT STRUCTURES IN DEVELOPING FLOW OVER A WAVY WALL (파형벽면이 있는 채널 유동의 응집 구조 연구)

  • Chang, Kyoung-Sik
    • Journal of computational fluids engineering
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    • v.17 no.2
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    • pp.93-99
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    • 2012
  • The present study focuses on the case of developing flow with in a channel containing a long array of sinusoidal waves (2a/${\lambda}$=0.1, ${\lambda}$=h, ${\lambda}$ is the wavelength, 2a is the wave height, h is the mean channel depth) at the bottom wall. The Reynolds number defined with channel height, h and the mean velocity, U, is Re=6,700. The channel is sufficiently long such that transition is completed and the flow is fully developed over the downstream half of the channel. For the case of an incoming steady flow with no resolved turbulence, the instantaneous flow fields in the transition region are characterized by the formation of arrays of highly-organized large-scale hairpin vortices whose dimensions scale with that of the roughness elements. The paper explains the mechanism for the formation of these arrays of hairpin vortices and shows these eddies play the primary role in the formation of the large-scale streaks of high and low velocity over the wavy wall region. The presence of resolved turbulence in the incoming flow, reduces the streamwise distance needed for the streaks to develop over the wavy region, but does not affect qualitatively the transition process. In the fully-developed region, isolated and trains of large-scale hairpins play an important role in the dynamics of the streaks over the wavy wall.

A Study on the Analysis of Landscape Preference in the Rural Settlement by Land Use Transition (토지이용변화를 이용한 농촌경관 선호성 분석에 관한 연구)

  • 서주환;최현상
    • Journal of the Korean Institute of Landscape Architecture
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    • v.27 no.2
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    • pp.69-79
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    • 1999
  • This study identifies the features of landscape elements on the fifteen districts with the idea of land use area and visual quantity of pictures by analyzing the air photo. Therefore, the sensibility of observer is comprehended through simulating the landscape evaluation and the landscape preference with using slide film. The study is divided into three periods to understand the transition of rural landscape as the social and cultural environments have been changed. The first period is the New Community Movement which affected the rapid change of social and cultural environments. The second and third periods are the prior and post time at the rearrangement of administration district in the Tae-Jeon Broad City. The result of this study is explained below part; 1. The transition of rural landscape has been occurred as the land use pattern has been altered. The change of pattern has affected an increase of the natural space and the structure change of agricultural productive space. 2. In the regression analysis, the regression model of landscape preference and land use ratio show; Landscape preference = 3.632 - 11.618 (Residential Area) - 4.227 (Equipped Farm). The explanation variables defined as Residential Area and Equipped Farm, and the relationship of those factors shows negative. Therefore, the increase of other building will make the rural landscape lower and worse.

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Identification of GATA2 and AP-1 Activator Elements within the Enhancer VNTR Occurring in Intron 5 of the Human SIRT3 Gene

  • Bellizzi, Dina;Covello, Giuseppina;Di Cianni, Fausta;Tong, Qiang;De Benedictis, Giovanna
    • Molecules and Cells
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    • v.28 no.2
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    • pp.87-92
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    • 2009
  • Human SIRT3 gene contains an intronic VNTR enhancer. A T > C transition occurring in the second repeat of each VNTR allele implies the presence/absence of a putative GATA binding motif. A partially overlapping AP-1 site, not affected by the transition, was also identified. Aims of the present study were: 1) to verify if GATA and AP-1 sites could bind GATA2 and c-Jun/c-Fos factors, respectively; 2) to investigate whether such sites modulate the enhancer activity of the SIRT3-VNTR alleles. DAPA assay proved that GATA2 and c-Jun/c-Fos factors are able to bind the corresponding sites. Moreover, co-transfection experiments showed that the over-expression of GATA2 and c-Jun/c-Fos factors boosts the VNTR enhancer activity in an allelic-specific way. Furthermore, we established that GATA2 and c-Jun/c-Fos act additively in modulating the SIRT3-VNTR enhancer function. Therefore, GATA2 and AP-1 are functional sites and the T > C transition of the second VNTR repeat affects their activity.

Equivalent Network Modeling of Slot-Coupled Microstripline to Waveguide Transition (슬롯 결합 마이크로스트립라인-도파관 천이기의 등가 회로 모델링)

  • Kim Won-Ho;Shin Jong-Woo;Kim Jeong-Phill
    • The Journal of Korean Institute of Electromagnetic Engineering and Science
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    • v.15 no.10 s.89
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    • pp.1005-1010
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    • 2004
  • An analysis method of slot-coupled microstripline to waveguide transition is presented to developed a simple but accurate equivalent circuit model. The equivalent circuit consists of an ideal transformer, microstrip open stub, and admittance elements looking into a waveguide and a half space of feed side from a slot center. The related circuit element values are calculated by applying the reciprocity theorem, the Fourier transform and series representation, the complex power concept, and the spectral-domain immittance approach. The computed scattering parameters are compared with the measured, and good agreement validates the simplicity and accuracy of the proposed equivalent circuit model.