• Title/Summary/Keyword: Block wall.

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Effect of Offset of Bearing on Radiation Sound and Vibration in the Gear System (기어장치에서 베어링의 설치위치가 소음특성에 미치는 영향)

  • 류성기;이중희
    • Journal of the Korean Society of Safety
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    • v.13 no.1
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    • pp.34-39
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    • 1998
  • This paper describes a evaluation method of sound power radiated from the vibrating faces of a single stage gear box using sound radiation. The vibration caused from meshing gears is transmitted to the gear box faces through shafts and bearings. A Boundary Element Method (BEM) is developed to calculate the sound power radiated from the faces with their velocity response which is based on the Building Block Approach (BBA). Radiation efficiency as well as the sound intensity on the surface of the gear box is also calculated. Sound power of the gear box is larger in the case that bearings have offset to the wall of the gear box than that bearings are on the center of the gear box. The sound power increases with the augmentation of the offset.

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Fabrication of Functional Microcapsule for Drug Delivery by using Droplet Phase Flow (Droplet 유동을 이용한 마이크로캡슐의 제작)

  • Jeong, Eun-Ho;Kim, Il;Go, Jeung-Sang;Kim, Kyung-Chun
    • Journal of the Korean Society of Visualization
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    • v.4 no.2
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    • pp.6-10
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    • 2006
  • The functional spherical microcapsules were produced through the innovative conjunction of the well-defined amphiphilic block copolymer and the stable droplet phase flow in the micro chemical plant. The microcapsules were formed to have hollow inner cavity and outer surface wall with nano-pores. To examine the potential of encapsulating foreign biochemical molecules, Congo-red dye was loaded into the microcapsule. The release performance in the specific surroundings such as temperature, pH and time was evaluated quantitatively.

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THE STATE OF THE ART OF THE INTERNAL PLASMA SPRAYING ON CYLINDER BORE IN AlSi CAST ALLOYS

  • Barbezat, G.
    • International Journal of Automotive Technology
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    • v.2 no.2
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    • pp.47-52
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    • 2001
  • For the wear protection of cylinder bore in aluminum cast material the internal plasma spraying technology offers a new economical solution. The size and the weight of the engine blocks significantly can be decreased in comparison with the traditional cast iron sleeves. The coefficient of friction between piston ring and cylinder wall sensitively can be reduced and the wear resistance increased from several factors. The paper gives an overview of the technology from the AlSi cast alloys for engine block to the non destructive testing technology used after the machining by diamond honing. The actual results in engines of different types also will be shown. The economical advantages of the plasma spraying (or the internal coating in cylinder bore also will be discussed in comparison with the different alternatives of technology. The aspect of the market introduction also will be discussed in this paper.

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A Study on Heat Transfer Performances of a Heat Pipe Heat Sink for Power Control Semiconductors (전력제어 반도체용 히트파이프 냉각기의 열전달 성능 연구)

  • 강환국;김재진;김철주
    • Korean Journal of Air-Conditioning and Refrigeration Engineering
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    • v.13 no.8
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    • pp.701-709
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    • 2001
  • In this days, heat pipe heat sink has been widely applied to power controllers for railway substations to remove heat from power semiconductors(diodes or thyristors). The heat pipe heat sink consists of a aluminum heating block for mounting the thyristor, 2~3 heat pipes and large number of aluminum fins. The present study was to get fundamental informations of the structure, design parameters and heat transfer performances of heat pipe heat sink. Series of operational test for a unit with 3 heat pipes were performed and its heat flow circuit was analysed from the experimentally obtained data on wall temperature distribution. Total resistance was ranged 0.02~$0.03^{\circ}C$/W for a power range from 40W to400W. The time to get the steady state was approximately longer than 20 minutes, and overshooting was not occurred during start up operation.

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Application of Z-plasty for Skin Defects by Mastectomy in a Dog (개에서 유방절제술에 의한 피부결손의 Z-plasty응용)

  • 김남수;최은경;정인성;최인혁
    • Journal of Veterinary Clinics
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    • v.19 no.4
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    • pp.440-442
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    • 2002
  • A fourteen-year-old mongrel female dog that was 22 kg and had two large mammary tumor lesions was admitted to the Animal Teaching Hospital of Chonbuk National University. Two large mammary tumor lesions were observed in the right caudal thoracic and the left inguinal mammary glands, which were sized 6 cm and 5 cm in diameter, respectively. These tumor lesions were removed by block mastectomy, then large skin defect of 7 cm diameter in caudal abdominal wall were recoverd by classic Z-plasty in both medial thigh. Classic Z-plasty was designed with 60 in angle and, with 6 cm in length of central limb in right medial thigh and 4 cm in left, respectively. This patient had been recoverd to normal gait and behavior at 20 days after the plastic operation.

Ground Improvement under Ship Collision Protection of Myodo-Gangyang Suspension Bridge Concerning of Sedimental Condition in Gyangyang Bay (광양만 퇴적이력을 고려한 묘도-광양간 현수교 충돌방지공 하부 지반보강)

  • Chang, Yong-Chai;Yoon, Tae-Seob;Kim, Kyung-Taek
    • Proceedings of the Korean Geotechical Society Conference
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    • 2008.10a
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    • pp.660-671
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    • 2008
  • The suspension bridge between Myodo and Gwangyang is located in the main navigation channel to Gwangyang Harbor. So, there is need for the collision protection against large vessels. As ship collision protection, artificial island with concrete block quay wall is planned. The risk analysis and non-linear numerical analysis are introduced to consider the ship collision effects. In the Gwangyang bay area, there are some different sedimental conditions in clayey stratums. For a desirable design, we classify into four zones and 2 layers in each zone, and then determine suitable soil properties considering these zones. As a ground improvement under artificial island, DCM and SCP methods are Planned.

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Static Performance of Reinforced Soil Segmental Retaining Wall (블록식 보강토 옹벽의 정적성능 평가)

  • Koh Tae-Hoon;Lee Sung-Hyuck;Lee Jin-Wook;Hwang Seon-Keun;Park Sung-Hyun;Lee Seung-Hoon
    • Proceedings of the KSR Conference
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    • 2003.05a
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    • pp.46-52
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    • 2003
  • In this study, the full scale testing method of the geogrid-reiuorced soil Segmental Retaining Walll(SRW) under the simulated train loading were proposed in order to evaluate the applicability of reinforced soil SRW in railway embankment. The train loading was simulated by the design static wheel load and the impact coefficient due to the train passing velocity. This test was focused on the static performance of reinforced soil SRW in terms of the following measuring systems ; the horizontal earth pressure displacement acting on the facing block and the tensile strain along the geogrid. The data gathered from this full scale testing was compared with numerical analysis results by FLAC.

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A Proposal on Rural House Reconditioning by the Field Survey Results (농촌주택의 실태 조사를 통한 개선 방안 연구 -충북지역을 중심으로-)

  • 이신호
    • Magazine of the Korean Society of Agricultural Engineers
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    • v.36 no.3
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    • pp.135-143
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    • 1994
  • The actural condition of rural house polts, houses and their attached facilities was surveyed in CHUNGCHEONGBUK-DO in order to find out existing residential problems. From the data collected, general influencing factors, housing/residential environmental qualities, and farmer's opinion on them were analyzed or obtained as the basic design criteria for future projects. The structural shape of rural housing should be developed on the basis of our traditional one. The materials of wall should be made from soil sourced one. Kitchin room and rest room should be improved in view of the Western style. Residential space should be harmonized our traditional one(reception of a guest preferred) with westernized living space(nuclear family life preferred). The plane planning of 'ㄷ' type would be generally preferred in the block planning of rural housing and attached facilities. Livestock pens and compost houses would be seperated from, while storehouses would be coexisted with a living space.

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Computer Simulation on the Characteristics of Daylight Distributions by Grating Louver System in a Pair Glass (복층유리 격자루버시스템의 주광특성에 관한 시뮬레이션 평가)

  • Park, Byoung-Chul;Choi, An-Seop
    • Proceedings of the Korean Institute of IIIuminating and Electrical Installation Engineers Conference
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    • 2009.05a
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    • pp.117-120
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    • 2009
  • New shading system, which is Grating Louver System into a pair glass, is proposed for integrated lighting system between Daylight Responsive Dimming Systems and shading system in this study. The optimized distance of louvers, which is to block direct sunlight into a space, is calculated. Grating Louver System was simulated using Desktop Radiance 2.0 of lighting simulation software for comparing daylight distribution and changes of control slope by distance from window to back wall with roller shading system controlled by sun profile angle.

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Effects of Air Compressibility on the Hydrodynamic Forces of a Bag

  • Lee, Gyeong-Joong
    • Journal of Hydrospace Technology
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    • v.1 no.1
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    • pp.14-28
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    • 1995
  • The hydrodynamic problem when the pressurized bag submerges partially into water and oscillates was formulated by Lee(1992), and the solution method was given, In his formulation, however, the compressilbility of air was neglected and the pressure inside the bag was assumed to be constant. In this paper, the formulation was done including the air compressibility and the wall to block fling around phenomenon. The compression process was assumed to be a isothermal process for a static problem, isentropic process for a dynamic problem. And the stability was analyzed for the static problem. Through the various numerical calculations, the forces and the shape of the bag were compared with those of a rigid body case, constant pressure case, and variable pressure case.

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