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A Non-consecutive Cloth Draping Simulation Algorithm using Conjugate Harmonic Functions (켤레조화함수를 이용한 비순차적 의류 주름 모사 알고리즘)

  • Kang Moon Koo
    • Journal of KIISE:Software and Applications
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    • v.32 no.3
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    • pp.181-191
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    • 2005
  • This article describes a simplified mathematical model and the relevant numerical algorithm to simulate the draped cloth on virtual human body. The proposed algorithm incorporates an elliptical, or non-consecutive, method to simulate the cloth wrinkles on moving bodies without resorting to the result of the past time-steps of drape simulation. A global-local analysis technique was employed to decompose the drape of cloths into the global deformation and the local wrinkles that will be superposed linearly The global deformation is determined directly by the rotation and the translation of body parts to generate a wrinkle-free yet globally deformed shape of cloth. The local wrinkles are calculated by solving simple elliptical equations based on the orthogonality between conjugate harmonic functions representing the wrinkle amplitude and the direction of wrinkles. The proposed method requires no interpolative time frames even for discontinuous body postures. Standing away from the incremental approach of time integration in conventional methods, the proposed method yields a remarkable reduction of CPU time and an enhanced stability. Also, the transient motion of cloth could be achieved by interpolating between the deformations corresponding to each static posture.

A STUDY OF THE EFFECTS OF THE LOW POWER DENSITY LASER ON THE MECHANICALLY EXPOSED PULP (저출력 레이저가 기계적 노출치수에 미치는 영향에 관한 연구)

  • Park, Dong-Sung;Lim, Sung-Sam
    • Restorative Dentistry and Endodontics
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    • v.14 no.1
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    • pp.109-118
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    • 1989
  • The purpose of this study was to investigate the bio-stimulating effect of low power density laser radiation on the mechanically exposed pulp. Class V cavities on dog's teeth were prepared and the pulps were mechanically exposed with a round bur. In control group, the exposed pulps were capped with $Ca(OH)_2$ powder and the cavities were sealed with Z.O.E.. In experimental group A, the pulps were irradiated with GaA1As laser for 5 minutes and then they were treated the same as control group. In experimental group B, the exposed pulps were covered by aluminum foil and sealed with Z.O.E. after they were irradiated with the laser as the experimental group A. In the all groups, the pulps were histopathologically observed at the time intervals of 1, 2 and 3 week after experiment and the results were statistically evaluated. The results were as follows: 1) In control and experimental groups, mild vascular congestion and bleeding was found in most of the specimens and for the new formation of dentin bridge, experimental group A had the most cases. The dentin bridge had discontinuous osteodentin like appearance without any dentinal tubules. Inflammatory cell infiltration consisted of acute and chronic inflammatory cell, and the formation of microabscess was also observed. 2) The degree of inflammatory cell infiltration was not significantly different among control group and experimental groups at 1 week, 2 week and 3 week. 3) The formation of new dentin bridge was not significantly different between control group and experimental group A at 1 week, but at 2 week and 3 week, experimental group A showed significantly more cases of new dentin formation than control groups. (P < 0.05). 4) Between control group and experimental group B, there was no significant difference in formation of the new dentin bridge at 1, 2 and 3 week. (P> 0.05). 5) There was no significant difference in formation of the new dentin bridge at 1 and 2 week between experimental group A and experimental group B, but at 3 week, the former significantly had more cases of new dentin bridge formation than the latter.(P < 0.05).

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Analysis of RTM Process Using the Extended Finite Element Method (확장 유한 요소 법을 적용한 RTM 공정 해석)

  • Jung, Yeonhee;Kim, Seung Jo;Han, Woo-Suck
    • Composites Research
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    • v.26 no.6
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    • pp.363-372
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    • 2013
  • Numerical simulation for Resin Transfer Molding manufacturing process is attempted by using the eXtended Finite Element Method (XFEM) combined with the level set method. XFEM allows to obtaining a good numerical precision of the pressure near the resin flow front, where its gradient is discontinuous. The enriched shape functions of XFEM are derived by using the level set values so as to correctly describe the interpolation with the resin flow front. In addition, the level set method is used to transport the resin flow front at each time step during the mold filling. The level set values are calculated by an implicit characteristic Galerkin FEM. The multi-frontal solver of IPSAP is adopted to solve the system. This work is validated by comparing the obtained results with analytic solutions. Moreover, a localization method of XFEM and level set method is proposed to increase the computing efficiency. The computation domain is reduced to the small region near the resin flow front. Therefore, the total computing time is strongly reduced by it. The efficiency test is made with a simple channel flow model. Several application examples are analyzed to demonstrate ability of this method.

Effects of Ginsenosides on the Mechanism of Histamine Release in the Guinea Pig Lung Mast Cells Activated by Specific Antigen-Antibody Reactions

  • Ro, Jai-Youl;Ahn, Young-Soo;Kim, Kyung-Hwan
    • The Korean Journal of Physiology and Pharmacology
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    • v.1 no.4
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    • pp.445-456
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    • 1997
  • We previously reported that some components of ginsenosides decreased mediator releases evoked by the activation of mast cells with specific antigen-antibody reactions. This study aimed to assess the effects of ginsenosides ($Rb_2$, Re) on the mechanism of histamine release in the mast cell activation. We partially purified guinea pig lung mast cells by using enzyme digestion, the rough and the discontinuous percoll density gradient method. Mast cells were sensitized with $IgG_1$ and challenged with ovalbumin (OA). Histamine was assayed by fluorometric analyzer, leukotrienes by radioimmunoassay. Phospholipase D (PLD) activity was assessed more directly by the production of $[^3H]phosphatidylbutanol$ (PBut) which was produced by PLD-mediated transphosphatidylation in the presence of butanol. The amount of 1,2- diacylglycerol (DAG) were measured by the $[^3H]DAG$ labeled with $[^3H]palmitic$ acid or $[^3H]myristic$ acid. Pretreatment of $Rb_2$ ($300\;{\mu}g$) significantly decreased histamine release by 60%, but Re ($300\;{\mu}g$) increased histamine release by 34%. Leukotrienes release in $Rb_2$ was decreased by 40%, Re was not affected in the leukotrienes release during mast cell activations. An increasing PLD activity during mast cell activation was decreased by the dose-dependent manner in the pretreatment of $Rb_2$, but Re pretreatment facilitated the increased PLD activity during mast cell activation. The amount of DAG produced by phospholipase C (PLC) activity was decreased by $Rb_2$ pretreatment, but Re pretreatment was not affected. The amount of mass DAG was decreased by $Rb_2$ and Re pretreatment during mast cell activation. The data suggest that $Rb_2$ purified from Korean Red Ginseng Radix inhibits the DAG which is produced by the activation of mast cells with antigen-antibody reactions via both phosphatidylinositide-PLC and phosphatidylcholine-PLD systems, and then followed by the inhibition of histamine release. However, Re increases histamine release by stimulation of DAG production, which is mediated by phosphatidylcholine-PLD system rather than by phosphatidylinositide-PLC system, but inhibits the mass DAG production. Thus, it could be inferred that other mechanisms play a role in the increase of histamine release during mast cell activation.

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Development of Improved Rock Bolt for Reinforcement of Fracture Zone in Slope and Tunnel (사면 및 터널에서의 암반 파쇄대 보강을 위한 개량형 록볼트 개발)

  • Kim, Soo-Lo;Kim, Jong-Tae;Park, Seong-Cheol;Kim, Tae-Heok;Kwon, Hyun-Ho;Jeong, Gyo-Cheol
    • The Journal of Engineering Geology
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    • v.20 no.1
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    • pp.101-109
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    • 2010
  • There are many slopes generally developed by excavation and cut slope with small steps on massive slopes of roads. Especially these cut slopes which excavating around fault fracture zone need a reinforcement technology in order to ensure safety. In the case of slope excavation, it is difficult to use the existing slope support at fracture zone because of geological characteristics. Especially the factor of safety decreases significantly due to the movement of blocks in bed rocks and the expansion of interspace of discontinuous planes in fractured zones caused by excavation. Thus an efficient reinforcement technique in accordance with geological properties of fracture zones needs to be developed because the existing slope support has a restricted application. Therefore it is necessary to develop the specialized rock bolt technique in order to ensure an efficient factor of safety for anomalous fracture zones in slopes and tunnels. The purpose of this study is to develop newly improved rock bolt to increase a supporting effect of the swellex bolt method used recently as a friction type in fracture zones.

Membrane Proteins and Their Antigenicity of Toxoplasma gondii (yoxoplusmg leondii의 세포막 단백 성분과 그 항원성)

  • Choe, Won-Yeong;Nam, Ho-U;Yu, Jae-Eul
    • Parasites, Hosts and Diseases
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    • v.26 no.3
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    • pp.155-162
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    • 1988
  • Surface membrane proteins of virulent RH strain and tissue cyst-forming Fukaya strain of Toxoplasma gondii were analysed by SDS-polyacrylamide gel electrophoresis after LPO-catalyzed surface iodination and lectin blotting, then identified the zoite-specific antigens. Prior to the analyses, purification of RH tachyzoites from mouse peritoneal exudate and of Fukaya bradyzoites from mouse brain tissues were performed by centrifugation - on the discontinuous Percoll density-gradient. Ta- chysoites were obtained at the interface of 50U and 60% Percoll solution and brain cysts were harvested at the interfaces of 40-50% and 50-60%, then bradyzoites were obtained by treating the cysts with hypertonic solution. The LPO-catalyzed iodination detected 15 KDa and 14 KDa proteins o( brady- zoites and 30 KDa protein of tachysoites as major bands with several other minor bands. But Con A blotting revealed some bands of 200 K∼50 KDa glycoproteins of bradyzoites and 52 KDa band as major and minor bands of 33 K∼20 KDa of tachyzoites. Phytohemagglutinin did not detect any band in the two forms. EITB with anti- Fukaya antibody and anti-RH antibody revealed cross-reactivities between the two forms. Despite the cross-reactivity, anti-Fukaya antibody reacted with 15 KDa band of bradyzoites specifically and, anti-RH antibody with 52 KDa, 30 KDa, and 25 KDa bands of tachyzoites, respectively. It was identified that 15 KDa protein in bradyzoite, which was not a glycoprotein, was a major membrane protein with sufficient antigenicity, and in the case of tacky- zoite, 52 KDa surface glycoprotein (gp52) with specific antigenicity might be added to the major surface protein, p30.

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An Exploration of Creativity Education Model (창의성 교육 모델의 탐색)

  • Kang, Choong-Youl
    • Journal of Gifted/Talented Education
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    • v.10 no.1
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    • pp.1-32
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    • 2000
  • Although it is widely acknowledged that enhancing creativity is an important educational theme on which schools should depend and embody their educational goal and activities, how to do it can be characterized as 'piecemeal' without a whole picture of it. Thus, school practices of creativity education has been disoriented, discontinuous, short-term, and peripheral in nature. In this practical context, a theoretical model of creativity education was developed in ways in which several theoretical concepts based on research findings on a variety of aspects of creativity education were compiled and organized. The core of the model was creative problem solving process to which the goals and the mediating variables of creativity education were connected in relational fashion. By giving repetitive opportunities for creative problem solving geared to producing the results that are novel and useful for the individual as well as the socity, it was conceptualized that two educational goals could be achieved: a short-term goal of developing creative potential of the individual and the long-term goals of self-actualization of the individual and contribution to the society. It is also conceptualized that creative problem solving can be influenced in positive manner by several mediating variables: content knowledge and skills, creative cognition, creative motivation and attitudes, and creative environment. The creative environment is composed of psychological and physical conditions and provides a basis for creativity education. The former three variables are conceptualized as necessary conditions for the effectiveness and efficiency of creative problem solving, when provided appropriately. The four mediating variables ware conceptualized as mutually affecting so that the development of one variable influences positively that of the other, and vice versa. In terms of practical perspective of teaching creativity, developing creative potential, self-actualization, and contribution to society are the goals; creative problem solving process is the methodology; content knowledge and skills, creative cognition, and creative motivation and attitudes are the content; and creative environment is the condition of creativity education. The model is not yet perfect but needs further explorations to make it more detailed in clarifying various relationships. For instance, how the creative problem solving process can be differentiated in teaching various subject matters is yet to be explored. Thus, the model proposed in this study should be regarded as a general model of creativity education, and is relatively sound to be adopted in school practices since it is based on the theoretical as well as empirical study findings on creativity. However, the proposed model needs to be validated through empirical researches in real teaching settings.

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Applicability of the mα-tangent Method to Estimate Plastic Limit Loads of Elbows and Branch Junctions (선형탄성해석과 mα-tangent방법을 이용한 배관 한계하중 평가 적용성)

  • Gim, Jae-Min;Kim, Sang-Hyun;Bae, Kyung-Dong;Kim, Yun-Jae;Kim, Jong-Sung
    • Transactions of the Korean Society of Mechanical Engineers A
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    • v.41 no.6
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    • pp.499-505
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    • 2017
  • In this study, the limit loads calculated by the $m_{\alpha}-tangent$ method based on the linear finite element analysis are compared with the closed form solutions that are proposed by various authors. The objects of the analysis is to select the elbow and the branch pipe which are representative structure of piping system. The applicability of the $m_{\alpha}-tangent$ method are investigated by applying it to cases with various geometries. The internal pressure and the in-plane bending moment are considered and the $m_{\alpha}-tangent$ method is in good agreement with the existing solutions in case of elbows. However, the limit loads calculated by the $m_{\alpha}-tangent$ method for branch junctions do not agree well with the existing solutions and do not show any tendency. The reason is a biased result due to the stress concentration of the discontinuous parts.

Precisely Nondestructive Diagnosis and Slope Stability of the Bonghwa Bukjiri Maaeyeoraejwasang (Rock-Carved Seated Buddha Statue), Korea (봉화 북지리마애여래좌상의 비파괴 정밀진단과 사면안정성 분석)

  • Cho, Ji-Hyun;Jo, Young-Hoon;Chun, Yu-Gun;Choi, Joon-Hyun;Lee, Chan-Hee
    • Journal of Conservation Science
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    • v.26 no.2
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    • pp.121-132
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    • 2010
  • The Bukjiri Maaeyeoraejwasang (National Treasure No. 201) consists of two-mica granite in medium size, which was the simbol of power in the region of the Silla period. Magnetic susceptibility of the host rock was measured as 0.41(${\times}10^{-3}$ SI unit), which has the similar range with surrounding outcrop. The Buddha developed parallel discontinuous plane of NE to SW strike and damaged seriously by exfoliation, granular disintegration and brown discoloration as 41.5%, 16.7% and 40.0%, respectively. As a result of the ultrasonic velocity, which was relatively weak values as 1,629m/s (Buddha area) and 1,549m/s (surrounding outcrop), improved about 900m/s compared to last treatment. From the results of the evaluation for slope stability, identified the possibility of toppling failure in the Buddha, and planar and wedge failure in host rock. Therefore, we suggest for the safely conservation of the Buddha, continuance monitoring for understand behavior of discontinuity system of the surface, and necessitate foundation reinforcement method for the rock which has the danger of collapse.

Physicochemical Study of the Wondong Fe-Pb-Zn Skarn Deposit, Korea (원동(院洞) Fe-Pb-Zn 스카른광상의 물리화학적(物理化學的) 특징(特徵))

  • Chang, Ho Wan;Chang, Byung Uck
    • Economic and Environmental Geology
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    • v.25 no.1
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    • pp.1-16
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    • 1992
  • The Wondong Fe-Pb-Zn deposit is located in endo and exoskarns formed along the contact between the Makkol limestone interbedding pelitic limestone of Ordovician age and quartz porphyry of Cretaceous age. At the Wondong mine, the endoskarn shows a discontinuous zonal arrangement from quartz porphyry to pelitic limestone as follows: unaltered quartz porphyry, weakly altered quartz porphyry zone, intensively altered pinkish quartz porphyry zone, garnet zone, and greyish white and fine-grained clinopyroxene zone developed at pelitic limestone side. In terms of chemical mass balance, intensively altered pinkish quartz porphyry relative to unaltered quartz porphyry shows substantial enrichments in $K_2O$, $Na_2O$, and HREE and depletions in MgO, CaO, total $Fe_2O_3$, and LREE. On the other hand, garnet zone of endoskarn is enriched in CaO, MnO, total $Fe_2O_3$, MgO and depleted in $K_2O$, $Na_2O$. $Al_2O_3$ seems to be determining inert component. Thus the behavior of elements indicates that the mobility of elements depends on the equilibration of hydrothermal fluid and minerals and affects on enrichments by fractionation from and depletions by partition to hydrothermal fluid, respectively. Traversing toward pelitic limestone from a central zone of exoskarn, the exoskarn also shows a zonal arrangement as follows: garnet zone, clinopyroxene zone, and decolored pelitic limestone. The arrangement of mineral assemblages in skarns of the Wondong mine is the result of an increase in CaO and $K_2O$ toward the pelitic limestone. Skarn and ore minerals were formed in the following sequence: early skarn, late skarn and magnetite, pyrite, sphalerite, galena, and molybdenite. On the basis of stabilities of mineral assemblages, physicochemical conditions of the late skarn and magnetite mineralization are estimated to be $350^{\circ}C{\leq}T{\leq}400^{\circ}C$ at 1 Kb, $-23{\leq}log\;fO_2{\leq}-18$, and $0.005{\leq}XCO_2{\leq}0.01$, while those of the early skarn to be $420^{\circ}C{\leq}T{\leq}550^{\circ}C$ at 1 Kb.

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