• 제목/요약/키워드: barrel

검색결과 541건 처리시간 0.024초

EFFECTS OF SKIRT PROFILES ON THE PISTON SECONDARY MOVEMENTS BY THE LUBRICATION BEHAVIORS

  • Jang, S.;Cho, J.
    • International Journal of Automotive Technology
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    • 제5권1호
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    • pp.23-31
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    • 2004
  • Secondary movements of piston in the bore clearance are closely related to the side impact to the engine block as well as many tribological problems. Some of the major parameters that influence these kinds of movements are piston profile shapes (barrel and flat), piston pin offsets and the magnitudes of bore clearances. In our study, computational investigations are performed about the piston movements in the bore clearance by changing the skirt profiles and piston offsets. In this work, it is found that curved profile and larger offset magnitude to thrust side provide better performance that has low side impact during the engine cycle.

과실의 포와송 비와 크리이프 컴프라이언스 보정 (Poisson's Ratio and Corrected Creep Compliance of Fruits)

  • 박종민;김만수
    • Journal of Biosystems Engineering
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    • 제20권2호
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    • pp.133-140
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    • 1995
  • The model of Poisson's ratio of the fruits was developed on the basis that the cylindrical fruits specimen became the barrel shape when it was being compressed. The model of the corrected creep compliance of the fruits was developed under considering the developed model of Poisson's ratio. Both of the Poisson's ratio and the corrected creep compliance of the samples showed the nonlinear viscoelastic behavior. Those models were a similar form, but their coefficients of the model were different, and these behaviors of the samples were well described by the nonlinear model as a function of the initial stress and time. Effects of storage condition and period on the Poisson's ratio of the samples were investigated, and comparisons between the corrected and the uncorrected creep compliance of the samples were made.

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휴대폰용 카메라 모듈에서 파면코딩을 통한 이미지 시스템 실험구현 (Experimental realization of an imaging system using wavefront coding in mobile phone camera)

  • 김종필;이상혁;박노철;박영필;박경수
    • 정보저장시스템학회논문집
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    • 제5권1호
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    • pp.36-40
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    • 2009
  • We describe the experimental realization of image system using wavefront coding in 3-Mega pixel mobile phone camera. We designed aspheric lens to extend the depth of field (DOF) using wavefront coding. In addition, through the aspheric lens and lens barrel manufacturing, we obtained a raw image from a camera module. In our method, the acquired images are restored in the spatial frequency domain using the proposed filter and the spatial frequency response (SFR) is calculated. The proposed filters are composed of image denoising filter using low band pass filter in frequency domain and restoration filter for image restoration. Finally, we achieve an enhanced image by super-resolution image processing. Visual examples are given to demonstrate the performance of the proposed filter.

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믹서의 가동 수 및 각도 변화에 따른 유동형 지붕 탱크의 유동특성 (Flow Characteristics of Floating Roof Tank with Varying the Number of Operation and Angle)

  • 김노형
    • 한국유체기계학회 논문집
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    • 제18권3호
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    • pp.20-25
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    • 2015
  • In this study, there are 6 mixers that are installed in a 600,000 barrel tank. We identified internal flow characteristics of floating roof tank with varying the number of operation from 4 to 6 because mixer is a variable that influence flow characteristics of the tank. And while varying an angle from Right $60^{\circ}$, Right $30^{\circ}$, Left $30^{\circ}$ to Left $60^{\circ}$, we identified internal flow characteristics of the tank. As a result, maximum velocity of flow was 0.02m/s stationarily when we changed the number of operation from 4 to 6. Maximum velocity of flow by change of an angle was from 0.42m/s to 0.47m/s. Therefore, we identified that these factors don't have a great influence on internal flow characteristics of a tank by investigating results with varying the number of operation and an angle.

DEVELOPMENT OF AN IMPROVED INSTALLATION PROCEDURE AND SCHEDULE OF RVI MODULARIZATION FOR APR1400

  • Ko, Do-Young
    • Nuclear Engineering and Technology
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    • 제43권1호
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    • pp.89-98
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    • 2011
  • The construction technology for reactor vessel internals (RVI) modularization is one of the most important factors to be considered in reducing the construction period of nuclear power plants. For RVI modularization, gaps between the reactor vessel (RV) core-stabilizing lug and the core support barrel (CSB) snubber lug must be measured using a remote method from outside the RV. In order to measure RVI gaps remotely at nuclear power plant construction sites, certain core technologies must be developed and verified. These include a remote measurement system to measure the gaps between the RV core-stabilizing lug and the CSB snubber lug, an RVI mockup to perform the gap measurement tests, and a new procedure and schedule for RVI installation. A remote measurement system was developed previously, and a gap measurement test was completed successfully using the RVI mockup. We also developed a new procedure and schedule for RVI installation. This paper presents the new and improved installation procedure and schedule for RVI modularization. These are expected to become core technologies that will allow us to shorten the construction period by a minimum of two months compared to the existing installation procedure and schedule.

Occurrence of Powdery Mildew on Safflower Caused by Sphaerotheca fuliginea in Korea

  • Kwon, Jin-Hyeuk;Kang, Soo-Woong;Lee, Heung-Su;Park, Chang-Seuk
    • Mycobiology
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    • 제28권1호
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    • pp.51-53
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    • 2000
  • The powdery mildew of safflower (Carthamus tinctorius L.) extensively occurred at 1999 at the experimental farm of Kyongsangnam-do Agricultural Research and Extension Services. Both sides of the leaves and the older stems were covered with the fungus, and then the leaves and stems turned yellow. The conidia, conidiophores and perithecia were observed on the leaf lesion. Perithecia were ellipsoidal, $80-117\;{\mu}m$ in diameter. Asci were subglobose and $84{\sim}99{\times}59{\sim}73\;{\mu}m$ in size. Ascospore were ellipsoidal to ovoid, and $15{\sim}34{\times}11{\sim}23\;{\mu}m$ in size. Conidia were ellipsoid to barrel-shaped, $25{\sim}37{\times}11{\sim}22\;{\mu}m$ in size and formed in long chains. The causal organism was identified as Sphaerotheca fuliginea. This is the first report on powdery mildew of safflower caused by Sphaerotheca fuliginea in Korea.

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MCNP코드를 이용한 영광3호기 방사선관리구역에서의 중성자 스펙트럼 계산

  • 한치영;김종경;조찬희;신상운;송명재
    • 한국원자력학회:학술대회논문집
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    • 한국원자력학회 1997년도 추계학술발표회논문집(1)
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    • pp.115-120
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    • 1997
  • 영광3호기 방사선관리구역에 대한 중성자선량률을 정확히 평가하기 위하여 MCNP4A 전산코드를 이용, 방사선관리구역에서의 중성자 스펙트럼 계산을 수행하였다. 영광3호기에 대한 보다 정확하고 정밀한 3차원 몬테칼로 모델을 구축하기 위하여 핵연료집합체 구성요소 및 원자로심을 둘러싸고 있는 baffle, barrel,압력용기 등을 정확하게 묘사하였으며, 특히 방사선관리구역 주위의 구조물에 대해서도 3자원 MCNP 모델을 구축함으로써 원자로심부터 방사선관리구역까지 완전한 몬테칼로 모사(full-scope Monte Carlo simulation)를 이용한 계산을 수행하였다. 계산결과는 에너지 구간에 따른 중성자속 스펙트럼으로 나타내었으며 이 결과를 바탕으로 중성자속에 대한 선량률 환산인자를 고려하여 중성자선량률을 계산할 수 있다.

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Head Up Display의 적응적 왜곡 보정시스템 (Adaptive Distortion Correction System of Head Up Display)

  • 지용석;김영섭;이용환;이명석
    • 반도체디스플레이기술학회지
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    • 제13권3호
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    • pp.57-60
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    • 2014
  • The distortion correction system of Head up display that is installed in vehicle has been studied both experimentally and theoretically for the removal of the optical lens distortion. A new adaptive correction method is having a decisive effect on correction in the optical lens distortion of Head up display. This adaptive correction system removes various distortion that has occurred because of the design tolerances of Head up display and the assemble tolerances into vehicle. It is especially efficient in removal of a barrel distortion and pin cushion of Head up display.

KICT-type 대구경 샘플러의 해상 적용성 검토 (Application of KICT-type Large Diameter Sampler for Offshore Ground Sampling)

  • 김영석;김영진;윤여원;정지원
    • 한국지반공학회:학술대회논문집
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    • 한국지반공학회 2008년도 추계 학술발표회
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    • pp.1365-1369
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    • 2008
  • A large diameter sampler (KICT-type large diameter sampler) was developed to take undisturbed samples from not only soft ground but also sandy and weathered ground. The KICT-type large diameter sampler was manufactured with the principle of triple core barrel sampling. In this study, the applicability to offshore ground sampling of the KICT-type large diameter sampler was confirmed at Inchoen Port construction site. And, in order to compare the quality of samples taken by the sampler with that of the traditional piston sampler, a series of laboratory tests were performed. From the test results, the samples taken by the KICT-type large diameter sampler showed higher quality than the traditional thin-walled tube samples.

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LSI패턴 데이타 고속처리용 양방향 스위칭 네트워크 설계 (Design of a Bidirectional Switching Network for High-Speed Processing of LSI Pattern Data)

  • 김성진;서희돈
    • 한국정보처리학회논문지
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    • 제1권1호
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    • pp.99-104
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    • 1994
  • 본 논문은 LSI의 물리적 레이아웃 설계시 다량의 패턴 데이타를 고속으로 처리할 수 있는 새로운 2차원 병렬처리 방법을 제안한고 메모리와 프로세서간에 데이타를 양방향으로 고속 전송 하는 스위칭 네트워크를 설계하였다.이스위칭 네트워크를 VHDL 설계 시스템을 이용하여 시뮬레이션하여 그 동작을 확인하였다.

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