• 제목/요약/키워드: internal shapes

검색결과 281건 처리시간 0.03초

수소저장금속의 형상과 변형 (Shapes and Deformation of the Hydrogen Absorption Metal)

  • 정영관;박규섭;이근진;김경훈;김세웅
    • 한국정밀공학회:학술대회논문집
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    • 한국정밀공학회 2003년도 춘계학술대회 논문집
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    • pp.1382-1385
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    • 2003
  • Deformation on shapes of the hydrogen absorption metal in this paper was investigated on hydrogen absorption-desorption cycling. In order to study this problem, the cold rolled palladium plate and the cold extrusion palladium bar as specimens had been used. By using the electrochemical method, the palladium specimens were cyclically hydrogenated in the 0.1 mol H$_2$SO$_4$ electrolyte. As results, it is noted that the thickness of the plate specimen gradually increased in increasing hydrogenation cycles whereas the width and the length decreased. But both the diameter and the length of the bar specimen increased with increasing hydrogenation cycles. Also, grains in the plate specimen were greatly deformed after hydrogenation cycling whereas internal grains in the bar specimen were pulverized. And deterioration of the hydrogen absorption rate of the bar specimen was lager than the plate specimen.

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Convergence Modeling and Reproduction of a Bigyeokjincheolloe (Bomb Shell) Based on Three-dimensional Scanning and 𝛾-ray Radiography

  • Kim, Da Sol;Jo, Young Hoon;Huh, Il Kwon;Byun, Sung Moon
    • 보존과학회지
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    • 제38권1호
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    • pp.55-63
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    • 2022
  • The Bigyeokjincheolloe (bomb shell), a scientific cultural heritage, has outstanding historical value for sustaining a gunpowder weapon of Joseon. In this study, the bomb shell was modeled through three-dimensional (3D) scanning centered on the external shape and 𝛾-ray radiography-based on the internal shape. In particular, to improve the contrast in the radiographic image, optimization and image processing were performed. After these processes, the thickness of the inner wall (2.5 cm on average) and the positions of the three mold chaplets were clearly revealed. For exhibition purposes, the 3D model of the bomb shell was output to a 3D printer and the output was rendered realistic by coloring. In addition, the internal functional elements, such as Mokgok, fuse, mud, gunpowder, and caltrops, were reproduced through handwork. The results will contribute to the study of digital heritages in two ways. First, the internal and external shapes of the bomb shell were modeled by fusing two different technologies, namely, 3D scanning and 𝛾-ray radiography. Second, the internal shape of the bomb shell was constructed from the original form data and the reproduction was utilized for museum exhibitions. The developed modeling approach will greatly expand the scope of museum exhibitions, from those centered on historical content to those centered on scientific content.

형상에 관한 문헌 고찰 -내경을 중심으로- (Study on Hyungsang in Nei Ching)

  • 강경화;백근기;김경철;이용태
    • 동의생리병리학회지
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    • 제16권3호
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    • pp.424-434
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    • 2002
  • In Jang-Sang theory, ‘Sang’ indicates ‘Hyung Sang’. The internal organs appear it's shapes(Hyung Sang) outward. ‘Hyung Sang’ is concept that was used on 「the book of changes」(周易) and 「Nei Ching」(內經) to means a thing's shapes and conditions. ‘Hyung’ is the shape, an organization composing a thing and ‘Sang’ is the symptom, an essence(a seed) immanenting a thing. To observe Hyung Sang, it have to apply the principle that ‘the sky and man correspond each other(天人相應)’. Usually ‘Hyung’ appears as shapes and ‘Sang’ appears as colors and conditions. Diagnosis on the basis of Hyung Sang put first the external expression of the five Jang six Bu organs and Jung-Ki-Shin-Hyul(精氣神血). So a doctor has to unite shapes, colors, pulse and symptoms(形, 色, 脈, 症) when diagnosis a patient. The theory of Hyung Sang includes the basic theories of the oriental medicine, the theory for Yin-Yang and the five element(陰陽五行論), organ picture(Jang-Sang), meridians(經絡學說), the five circuit phases and the six atmospheric influences(運氣學說), physical constitution(體質學說). I think that treatment based on Hyung Sang is shown the essence of the oriental medicine well. In the future, I think, we need to study more about the theory of Hyung Sang.

고혈압 환자에서 혈압 조절 여부에 따른 신상(脤象) 및 삶의 질 비교 (A Comparison of Controlled and Uncontrolled Hypertension Groups Regarding Pulse Shape and Quality of Life)

  • 최인영;한창호;최동준;정승현;신길조;이원철
    • 대한한방내과학회지
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    • 제30권4호
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    • pp.880-892
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    • 2009
  • Objectives : This study is about a comparison of controlled and uncontrolled hypertension groups regarding pulse shape and quality of life. We aimed to find out if pulse shape would be able to help with hypertension treatment and care. Methods : We surveyed "controlled and uncontrolled hypertension patients" using SF-36, HTN QoL (measurement scale for the quality of life in hypertensive patients) and 3-D MAC pulse analyzer for pulse shape. Results : The uncontrolled hypertension group tended to have a sink pulse in the left cun. right guan & chi parts compared to the controlled hypertension group. Within the controlled hypertension group, patients who had a float pulse shape in both guan parts had a higher quality of life than patients who had a normal pulse shape. And the patients who had a normal pulse shape in both chi parts had a higher quality of life than patients with a slow or fast pulse shape. Within the uncontrolled hypertension grouP. the patients who had a normal pulse shape in right guan part had a higher quality of life than those with a choppy pulse shape. Nevertheless, these results were limited to only a few quality of life issues and were inconsistent in relation to specific pulse shapes. Conclusion : If we have more samples and better methods for collecting data, we will have better results, allowing us to improve our ability to predict and treat hypertension.

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Effect of Surface Energy Anisotropy on the Equilibrium Shape of Sapphire Crystal

  • 최정해
    • 한국세라믹학회지
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    • 제39권10호
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    • pp.907-911
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    • 2002
  • Using the two-dimensional Wulff plot, the equilibrium shape of a sapphire crystal was investigated as a function of surface energy anisotropy. Depending on the relative values of surface energy for various facet planes, the projected shape of equilibrium sapphire was determined to be rectangle, parallelogram, hexagon or octagon. The results are compared with the experimentally observed shapes of internal cavities of submicron range in sapphire single crystals.

크랭크 축의 모우드 해석에 관한 연구 (A study on modal analysis of a crankshaft)

  • 박윤식;제양규;오동엽
    • 오토저널
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    • 제7권4호
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    • pp.67-72
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    • 1985
  • An analytical and experimental modal analysis is carried out upon a crankshaft of a four cylinder internal combustion engine for studying dynamic characteristics of the shaft. Influence coefficient method is adopted in modelling the object and the calculated dynamic properties are directly compared with the experimentally obtained torsional and bending natural frequencies and mode shapes. It is found that the test results are well agree with the outputs from analytical model especially in low harmonics.

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Static and free vibration behaviour of orthotropic elliptic paraboloid shells

  • Darilmaz, Kutlu
    • Steel and Composite Structures
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    • 제23권6호
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    • pp.737-746
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    • 2017
  • In this paper the influence of aspect ratio, height ratio and material angle on static and free vibration behaviour of orthotropic elliptic paraboloid shells is studied by using a four-node hybrid stress finite element. The formulation of the element is based on Hellinger-Reissner variational principle. The element is developed by combining a hybrid plane stress element and a hybrid plate element. A parametric study is carried out for static and free vibration response of orthotropic elliptic paraboloid shells with respect to displacements, internal forces, fundamental frequencies and mode shapes by varying the aspect and height ratios, and material angle.

접선유입 방식 여과집진기의 내통형상 변화에 따른 집진특성 연구 (A Study on the Filtration Characteristics of Baghouse with Tangential Inlet Depending on the Shape of Inner Tube)

  • 최호경;박석주;임정환;김상도;박현설;박영옥
    • 대한기계학회:학술대회논문집
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    • 대한기계학회 2001년도 춘계학술대회논문집E
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    • pp.158-161
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    • 2001
  • A new type baghouse with tangential inlet and inner tube was developed and it's performances were evaluated. Experiments with variable shapes of inner tube were performed to suggest an optimum shape of inner tube which might decrease the dust loading onto bag filter surface and the amount of reentrained particles by internal gas flow. The dust loading was lower when inner tubes parallel to outer casing exist. When an inner tube covering around the lower portion of bag filters was used, the dust particles detached from the filter surface by cleaning process were reentraind by internal recirculating gas flow.

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노면상태를 고려한 전차 궤도 고무의 열발생에 관한 연구 (Study on the Heat Generation of Tank Track Rubbers under the Consideration of the Road Conditions)

  • 김병탁;김광희;윤문철
    • 한국자동차공학회논문집
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    • 제10권3호
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    • pp.166-175
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    • 2002
  • Tank track rubbers, which undergo dynamic stresses and strains under various road conditions, leads to a result of considerable internal temperature rise due to the heat generation. Since rubber materials are not fully elastic, a part of the mechanical energy is converted into heat because of the hysteresis loss. Heat generation without adequate heat dissipation leads to heat build-up, i.e. internal temperature rise which, if excessive, exerts a bad influence upon the performance and the life of the tank track rubbers. The purpose of this paper is to predict temperature distributions of the rubber components off tank track subjected to complex dynamic loads under various read conditions. In steady state analysis temperature fields are displayed in contour shapes, and in unsteady analysis the temperature variations of some important nodes are represented graphically with respect to the running time of the tank.