• Title/Summary/Keyword: upper structures

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A Study on the Shape Design and Nonlinear Analysis of Elastomeric Spherical Bearings for Railway Bridge Systems (철도교용 반구면 탄성체 베어링의 형상설계 및 해석에 관한 연구)

  • Oh, Ju;Cho, Hyun-Jin;Lee, Wan-Ha;Park, Jin-Young;Park, Kun-Nock
    • Proceedings of the KSR Conference
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    • 2009.05a
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    • pp.589-592
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    • 2009
  • In this paper is presenting the shape design and elastomer bearings, which functioned as a joint connecting sub-structures and upper-structures with a railway bridge bearing systems. The elastomeric spherical bearing shaped and composed of alternated 17-layered metal shim plates and 18-layered elastomer plates, respectively. The elastomeric spherical bearing a high compressive load for perpendicular axis to layered plates and flexible motions are provided coincidently for other axes. The three types of elastomers, which were developed due to a designed shear modules were applied. Nonlinear analysis based on the material properties of designed bearing were accomplished. Therefore, the Nonlinear Analysis results were compared with the calculation results and the optimized shapes were designed.

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The Flow Field Structures of In-lined Double Jet-in-Cross Flow at Low Velocity Ratio (낮은 속도비에서의 직렬 이중 제트-교차흐름의 유동 구조)

  • Lee, Ki-Young
    • Journal of the Korea Institute of Military Science and Technology
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    • v.18 no.4
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    • pp.415-422
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    • 2015
  • The flow field structures of dual jet-in-cross-flow were examined experimentally for in-lined perforated damage holes configuration using particle image velocimetry. Ensemble averaged in-plane velocity and vorticity data in the jet were determined to study the mean jet structure. Jets are formed by pressure differences between upper and lower airfoil surface. The flow structure of vicinity of the thru holes consist of a vortical structure that wrap around the jets like a horseshoe and develop further downstream through a pair of stream-wise vortices. The shape, size and location of the horseshoe vortex were found to be dependent on the angle of attack. In spite of the existence of battle damage holes, the effect on the control force was insignificant when the damage size was not large enough.

Fabrication of SOI structures whit buried cavities by SDB and elelctrochemical etch-stop (SDB와 전기화학적 식각정지에 의한 매몰 cavity를 갖는 SOI구조의 제작)

  • 강경두;정수태;류지구;정재훈;김길중;정귀상
    • Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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    • 2000.11a
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    • pp.579-582
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    • 2000
  • This paper described on the fabrication of SOI(Si-on-insulator) structures with buried cavities by SDB technology and eletrochemical etch-stop. The cavity was fabricated the upper handling wafer by Si anisotropic etch technique. SDB process was performed to seal the fabricated cavity under vacuum condition at -760mmHg. In the SDB process, captured air and moisture inside of the cavities were removed by making channels towards outside. After annaling(100$0^{\circ}C$, 60 min.), the SDB SOI structure was thinned by electrochemical etch-stop. Finally, it was fabricated the SDB SOI structure with buried cavities as well as an accurate control and a good flatness.

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Effects of Soil Nonlinearity Characteristics on the Seismic Response of KNGRStructures (지반의 비선형 특성이 차세대원전 구조물의 지진응답에 미치는 영향)

  • 장영선
    • Proceedings of the Earthquake Engineering Society of Korea Conference
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    • 1999.10a
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    • pp.137-146
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    • 1999
  • The SSI(Soil-Structure Interaction) analyses are being performed for the KNGR(Korean Next Generation Reactor) design because the KNGR is developed as a standard nuclear power plant concept enveloping various soil conditions. the SASSI program which adopts the flexible volume method is used for the SSI analyses. The soil curves used in the three dimensional SSI analyses of KNGR Nuclear Island(NI) structures are based on the upper bound shear modulus curve and lower bound damping degradation on SSI response the average shear modulus curve with average damping curve was used for two soil cases. This study presents the results of the variances by using different soil nonlinearity parameters based on the paametric SSI analyses. The results include the maximum member forces(shear and axial force) at the base of the NI structures and the 5% damping Floor Response Spectra (FRS) at some representative locations at the top of the NI superstructures. They are also compared together with the enveloped SSI results for eight soil cases and fixed-base analysis for rock case by using two control motions.

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Behavior and Hysteresis Characteristics of Traditional Timber Framers under Lateral Load (전통 문화재 목조 프레임의 횡하중에 대한 거동 및 이력특성)

  • 이필성
    • Proceedings of the Earthquake Engineering Society of Korea Conference
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    • 1999.10a
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    • pp.396-403
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    • 1999
  • This experimental study investigates the hysterestic behavior of traditional timber frames subjected to lateral loads. Prototype frames for this study were selected from one of typical national treasures for timber structures in Korea. For simplicity roof structures and braket systems were excluded from specimens and the joint behavior of beam-to-column system were presumed to have crucial effect on their global behavior. The experimental observation showed stiffness degradation and slip after experiencing initial yield and the first cycle at a new larger displacement due to inherent gaps in traditional timber connection and gradual indentation of interfaces, The cyclic behaviors of all specimens were similar to those os modern timber frames with bolt and nail connections. Additional structural members such as an upper beam and clay-filled wall increased the initial stiffness strength and energy dissipation. It is expected that collapse of Korean traditional timber frames under lateral load is mainly caused from P-$\Delta$ effects rather than local member failure.

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Study on dryout heat flux of axial stratified debris bed under top-flooding

  • Wenbin Zou;Lili Tong;Xuewu Cao
    • Nuclear Engineering and Technology
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    • v.56 no.2
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    • pp.636-643
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    • 2024
  • The coolability of the debris bed with a simulant of solidified corium is experimentally studied, focusing on the effects of the structure of the axial stratified debris bed on the dryout heat flux (DHF). DHF was obtained for the four structures with different particle sizes for the axial stratified debris bed under top flooding. The experimental results show that the dryout position of the axial stratified debris bed is formed at the stratified interface indicated by the temperature rise, and the DHF of the axial stratified bed is much lower than that of the homogeneous bed packed with the upper small particles. To predict the dryout heat flux of the stratified debris beds, by considering the properties of the mixed area, a one-dimensional dryout heat flux model of the porous medium is derived from a water and vapor momentum equation for porous medium, two-phase permeability modifications, interfacial drag, and the correlation between capillary pressure and liquid saturation and verified with the experimental data. The modified model can give reasonable results under different structures.

Development of a Circular Displacement Meter (원형 변위계 개발)

  • Nakhoon Shim;Ikchang Choi
    • Journal of Sensor Science and Technology
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    • v.33 no.4
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    • pp.209-215
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    • 2024
  • Generally, a straight displacement meter is used to obtain displacement data to verify the safety of structural members and structures. A straight displacement meter is also used to measure the absolute displacement in research laboratories or safety inspection sites such as bridges and buildings. In this study, for structures in which the displacement sensor could not be fixed at the location where the displacement was to be measured, a circular displacement meter was manufactured to measure the displacement by installing a displacement gauge on the structure itself. In other words, when measuring the horizontal displacement of an upper part, such as a wind tower, a circular displacement meter was installed inside the wind tower to integrate it with the structure, applying the principle that the structure itself can be used as a displacement meter. This circular displacement meter can be installed and used inside a circular structure. Whereas in the case of a telephone pole, it can be installed outside to measure displacement. It can be manufactured in various sizes and used.

Extracuterine Pregnancy in a Bitch (개의 자궁외 임신 증례)

  • 김휘율;한규보;김현수;김종성;임희란
    • Journal of Veterinary Clinics
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    • v.17 no.1
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    • pp.275-278
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    • 2000
  • A 3-year-old yorkshire terrier was examined because of the green-like vaginal discharge. Abdominal ultrasonographs revealed dead fetuses in the abdominal cavity. Surgical exploration revealed fetuses located in the region of the uterine wall, the omentum, the ileum, and the upper right side of the liver respectively. Fetal structures were removed and an ovariohysterectomy was performed. The abdominal cavity was flushed with warm saline and then the incision closed. These fetuses were at different stages of development. It was suggested that the development of the fetuses apparently continued in extrauterine pregnancy until the blood supply became inadquate for further growth.

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Pulmonary Blastoma -A Case Report- (폐아세포종 -수술치험 1례-)

  • 금동윤
    • Journal of Chest Surgery
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    • v.27 no.10
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    • pp.868-873
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    • 1994
  • We experienced a very rare case of pulmonary blastoma in a 29 year old female. She complained of left chest pain and dyspnea for 1 month. The characteristic feature of this tumor is it`s biphasic pattern consisting of a spindle cell stroma containing glandular structures. A serial check of simple chest X-ray and computed tomography revealed a growing huge lung mass occupying whole left thorax. We successfully removed the upper lobe of left lung with a huge tumor mass. Pathologic study revealed this tumor as pulmonary blastoma. We report a case with review of literature.

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Two Cases of Peripheral T-Cell Lymphoma Arising in Inferior Turbinate (하비갑개에 발생한 말초성 T세포 림프종 2례)

  • 김보형;강성호;임대준;조영찬
    • Korean Journal of Bronchoesophagology
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    • v.7 no.2
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    • pp.184-187
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    • 2001
  • Peripheral T-cell lymphoma, which characterized by progressive ulceration and necrosis of the upper aerodigestive tract or midline facial structures, is rare disease in the otolaryngologic field. We recently experienced a case, revealed histopathologically peripheral T-cell lymphoma, involving inferior turbinate without any evidence of involving other organs. In this paper, we report two cases of peripheral T-cell lymphoma who was treated chemotherapy and concurrent radiation therapy.

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