• 제목/요약/키워드: and hood

검색결과 395건 처리시간 0.024초

산업환기공학에 대한 전산유체역학의 응용가능성 (Applicability of Computational Fluid Dynamics on Industrial Ventilation Engineering)

  • 하현철;김태형;심광진
    • 한국산업보건학회지
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    • 제8권2호
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    • pp.163-177
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    • 1998
  • Computational Fluid Dynamics(CFD) was applied to predict air flow around the hoods : circular hoods, square hoods, and push-pull hoods. A commercially available CFD software, CFD-ACE(Ver. 4.0), was tested, which is based on the finite volume method using the ${\kappa}-{\varepsilon}$ turbulence model. Numerical results were compared with the experimental, analytical and numerical results from other studies. CFD solutions showed an excellent agreement with the previous experimental and numerical results. It is promising that CFD techniques could be applied on the variety of complex problems in the industrial ventilation engineering.

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풍동실험에 의한 승용차의 최적외형결정에 관한 연구 (Determination of aerodynamic configuration of passenger car by wind tunnel experiment)

  • 김근호;노오현;조경국
    • 오토저널
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    • 제5권2호
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    • pp.56-63
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    • 1983
  • The aerodynamic characteristics of the most popular car (PONY 2) produced in Korea have been experimentally investigated by Seoul National University's wind tunnel. The model (PONY 2) chosen for the wind tunnel was a 1/5 scale of the original car without simulated underbody, cooling air flow and accessories. The measured aerodynamic drag coefficient corrected by JARI formula is 0.45 which is very close to those of small foreign cars. To see the effect of the different configurations on the aerodynamic drag, the modifications have been made by changing the hood slope and backlight slope, and putting the add-on-aerodynamic devices on the orignal shape. The rear spoiler was found the most effective one to reduce the aerodynamic drag. It may be concluded that the considerable aerodynamic drag reduction can be achieved by changing the slopes and A-O-A devices at the proper places of the car.

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철도차량 실대형 화재안전 성능평가 장치 설계 (Design of the Full-Scale Fire Safety Evaluation Facility for Railroad Vehicle Fire)

  • 유용호;김흥열
    • 한국화재소방학회:학술대회논문집
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    • 한국화재소방학회 2008년도 춘계학술논문발표회 논문집
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    • pp.222-225
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    • 2008
  • To prove a lot of technical difficulties related to the safety management of a railroad fire effectively, we design for the full-scale fire test facility of the railroad vehicle. It will be consist of major 3 part - duct system with smoke cleaning system, measuring section and gas analysis system. The CFD simulation was also carried out to design of the hood and duct system optimization. The results will be help for basic research of the railroad fire safety.

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공동주택 연도 내의 자연 대류를 고려한 열-유동 해석 (Numerical Study on the Natural-Convection in a Shaft of an Apartment)

  • 박성근;김상규;용호택;최형권
    • 대한설비공학회:학술대회논문집
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    • 대한설비공학회 2005년도 동계학술발표대회 논문집
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    • pp.88-93
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    • 2005
  • In this paper, the heat and fluid flow analysis in a shaft of an apartment has been performed in order to investigate the pressure distribution inside a shaft considering both natural and forced convection. The present CFD approach can be used in estimating the capacity of roof ventilator of an apartment reasonably. Furthermore, flow patterns inside a shaft have been examined for some operating conditions of hood system.

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Estimating multiplicative competitive interaction model using kernel machine technique

  • Shim, Joo-Yong;Kim, Mal-Suk;Park, Hye-Jung
    • Journal of the Korean Data and Information Science Society
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    • 제23권4호
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    • pp.825-832
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    • 2012
  • We propose a novel way of forecasting the market shares of several brands simultaneously in a multiplicative competitive interaction model, which uses kernel regression technique incorporated with kernel machine technique applied in support vector machines and other machine learning techniques. Traditionally, the estimations of the market share attraction model are performed via a maximum likelihood estimation procedure under the assumption that the data are drawn from a normal distribution. The proposed method is shown to be a good candidate for forecasting method of the market share attraction model when normal distribution is not assumed. We apply the proposed method to forecast the market shares of 4 Korean car brands simultaneously and represent better performances than maximum likelihood estimation procedure.

굽힘 첨가 박막요소에 의한 알루미늄 샌드위치 판재 성형공정의 단면 유한요소 해석 (Sectional Finite Element Analysis of Forming Process of Aluminum Sandwich Sheet by Bending Augmented Membrane Elements)

  • 이재경;금영탁;유용문;이명호
    • 소성∙가공
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    • 제10권2호
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    • pp.91-100
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    • 2001
  • A sectional FEA program is developed lot analyzing forming processes of sandwich sheets, which are intensively used recently as a lightweight material of an automobile body. The aluminum sandwich sheet consists of two aluminum skins and a polyprophylen core in between. The aluminum sandwich sheet is dominantly effected by the bending effects in small radius of curvature, so that an appropriate description of bending effects is required to analyze the forming processes. For the evaluation of bending effects, the bending equivalent forces are calculated from the bending moment computed using the curvature of the tool and are added to the membrane stretch forces. To verify the validity of the developed program the sectional FEA results in stretch/draw forming Processes of a square cup and draw forming Processes of an outer hood panel were compared with the measurements.

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여학생 복식이 한복변천에 끼친 영향에 관한 연구 (A study on the affect to the transition of Korean clothing of the clothing of girl students)

  • 조효순
    • 대한가정학회지
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    • 제35권3호
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    • pp.307-318
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    • 1997
  • I observed the important factors of clothing transition - Changes of Korean clothing & reception of Western-style dress - through the survey of the clothing of girl students during the period of enlightenment(1900∼1945) in this study as follows. 1) Stop to use of a long hood an old-fashioned woman shawI(once used to cover th head and upper body when going out). 2) Appearance of same colored Korean costume of the upper and lower sides. 3) Appearance of a short seamless one-piece skirt with a pair of shoulder girdles. 4) Appearance of school uniform, upper white lower black-Korean costume. 5) Appearance of school uniform, Western style. 6) Appearance of sports-wear. 7) Reformation of under-wear. 8) Appearance of short hair. 9) Appearance of socks & stockings and shoes.

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샌드위치 판재의 차량적용 기술개발 (Development of Application Technique for a Car Body with Aluminium Sandwich Panels)

  • 이명호;유용문;윤의박;이경남;이중윤;금영탁
    • 소성∙가공
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    • 제7권6호
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    • pp.603-609
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    • 1998
  • An aluminium sandwich sheet is the material fabricated by adhering two aluminum panels to one plastic core. When it has the same bending stiffness as an steel panel it is 65% lighter than steel panel and 30% lighter than aluminum panel. Therefore it is notified exclusively as good substitutive materials for steel body to improve fuel efficiency. An aluminium sandwich sheet, however, has a problem of the lower formability than steel in automotive application. In this paper we intend to develop application technologies of an aluminum sandwich sheet for auto body panels from selecting composed materials of aluminium sandwich sheets to fabricating prototype. We selected aluminium sandwich panels fabricated by Hoogovens company. Through formability tests we have designed the hood part on auto body panels and fabricated a mould and a prototype.

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Three New Species of Anthessius (Copepoda, Cyclopoida, Anthessiidae) Associated with Mollusks

  • Lee, Jimin;Kim, Il-Hoi
    • Animal Systematics, Evolution and Diversity
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    • 제37권3호
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    • pp.187-204
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    • 2021
  • Three new copepod species of Anthessius are described as associates of mollusks. Anthessius tuberculatus n. sp. associated with the bivalve Asaphis violascens (Forsskal in Niebuhr, 1775) in Kosrae, Micronesia bears a pair of dorsal tubercles on the fifth pedigerous somite. Anthessius rarus n. sp. is associated with the aplysiid gastropod Dolabella auricularia (Lightfoot, 1786) in Bohol, the Philippines and has elongate caudal rami which are about 5.2 times as long as wide. Anthessius cucullatus n. sp. associated with the aplysiid gastropod Aplysia kurodai Baba, 1937 in Korea has a hood-like dorsal expansion on genital double-somite of the female.

보행자 보호용 프론트 엔드 모듈(FEM)의 냉각성능에 관한 연구 (Studies on the Cooling Performance of Front End Module for Pedestrian Protection)

  • 신윤혁;김성철
    • 한국자동차공학회논문집
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    • 제20권6호
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    • pp.67-72
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    • 2012
  • Novel Front End Module(FEM) with improved pedestrian protection is very important to reduce the severity of pedestrian injury. The FEM needs to have enough space from hood to absorb the energy from any pedestrian collision. In this study, the cooling performance of the FEM to cool the engine was investigated under 25% height reduction. The results indicated that the cooling performance analysis was about 86% level compared to that of the conventional FEM. Also, good qualitative agreement between CFD predictions and experimental measurements was found. This FEM needs the cooling performance enhancement for changed air flow path at the frontal part of vehicle. Therefore, we showed an improved performance using air guide setup and shape modification under the high load condition.