• 제목/요약/키워드: bell

검색결과 1,028건 처리시간 0.028초

입구 벨마우스 형상에 따른 냉장고 원심홴의 성능에 대한 수치적 분석 (Numerical analysis on the performance of centrifugal fans according to shapes of inlet bell-mouth in a refrigerator)

  • 김상현;허승;정철웅;김태훈
    • 한국소음진동공학회:학술대회논문집
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    • 한국소음진동공학회 2011년도 추계학술대회 논문집
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    • pp.737-742
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    • 2011
  • Because of complex structure of inlet and outlet flows, the performance of centrifugal fans used in a household refrigerator is affected by many parameters of duct system surrounding the fans. In this paper, the performance of a centrifugal fan is numerically analysed according to shapes of inlet bell-mouth. To improve performance of the centrifugal fan, some design parameters are selected for comparison. On a basis of these comparison, optimum shape of inlet bell-mouth is proposed to maximise the flow rate of the fan.

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T-sum of bell-shaped fuzzy intervals

  • 홍덕헌
    • 한국데이터정보과학회:학술대회논문집
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    • 한국데이터정보과학회 2006년도 추계 학술발표회 논문집
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    • pp.81-95
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    • 2006
  • The usual arithmetic operations on real numbers can be extended to arithmetical operations on fuzzy intervals by means of Zadeh's extension principle based on a t-norm T. A t-norm is called consistent with respect to a class of fuzzy intervals for some arithmetic operation if this arithmetic operation is closed for this class. It is important to know which t-norms are consistent with a particular type of fuzzy intervals. Recently Dombi and Gyorbiro proved that addition is closed if the Dombi t-norm is used with two bell-shaped fuzzy intervals. A result proved by Mesiar on a strict t-norm based shape preserving additions of LR-fuzzy intervals with unbounded support is recalled. As applications, we define a broader class of bell-shaped fuzzy intervals. Then we study t-norms which are consistent with these particular types of fuzzy intervals. Dombi and Gyorbiro's results are special cases of the results described in this paper.

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Tube의 형상 및 표면특성에 의한 Shell-and-Tube 열교환기의 열전달 성능 (The Performance in Shell-and-Tube Heat Exchangers with Configuration and Surface Characteristics of Tube)

  • 김성일;박기호;전원표
    • 대한기계학회:학술대회논문집
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    • 대한기계학회 2008년도 추계학술대회B
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    • pp.2316-2321
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    • 2008
  • This paper presents an improved performance of heat transfer for shell-and-tube and thermal analysis based on the Bell-Delaware method for single tube. Heat transfer has been compared for a smooth tube, helical tube and surface-coated tube. In general, the results showed that properly designed helical tube and surface-coated tube offer a significant improvement in heat transfer. The numerical results derived from the Bell-Delaware method for the shell-side heat transfer coefficient were verified with experimental results. The thermal analysis aids significantly in the solution of the design problem.

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인체와 성덕대왕 신종의 진동 특성 비교 연구 (A Study on Comparison between the Vibration Characteristics of the King Songdok Bell and the Human Body)

  • 전종원;진용옥
    • 한국정보처리학회논문지
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    • 제7권10호
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    • pp.3119-3127
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    • 2000
  • 본 논문은 성덕대왕 신종과 인체의 진동 특성의 상관관계를 분석함으로서 진동 특징 추출의 새로운 방안을 도출하기 위한 연구이다. 신종의 종, 움통, 울림통과 기타 비대칭적 요소들을 인체의 몸체, 성도, 횡경막과 인체구조의 비대칭적 요소들에 대비시켜 각각의 음향 특성들을 실험을 통하여 비교 분석하였다. 실험결과, 대비시킨 각 요소들의 음향 특성이 매우 흡사하여, 신종의 소리 특성에 관한 정보가 인체의 진동 전달 특성을 분석하는 데 있어서도 매우 유용하게 적용될 수 있다는 것을 확인하였다.

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대심도 부산점토에 적용된 종저말뚝(Belled Shaft foundation)의 수치해석 연구 (Numerical Analysis of Belled Shaft Foundation in Thick Pusan Clays)

  • Rao, K.G.
    • 한국지반공학회:학술대회논문집
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    • 한국지반공학회 2006년도 춘계 학술발표회 논문집
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    • pp.530-535
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    • 2006
  • The Pusan clays are soft and thick deposits and in some places, they reach even up to 50-70m. So, the pile foundations are inevitable in almost all cases. But they are significantly expansive when the length of the pile reaches about 70m. In this study, a comprehensive parametric study has been carried out in order to reduce the pile length and number of piles required in turn the cost of the foundation for particular building. A belled shaft pile has been optimized for a typical soil profile using the PLAXIS (FEM code). These results have shown a new direction of the pile foundation in Pusan, Korea. The results including the variation of contact pressures at the bottom of the bell, optimization of the angle of the bell and height of the bell in terms of the diameter of the shaft. And also, the design curves have been generated so that they can be directly used for design of belled shaft foundations. However, the structural strength criterion is being checked in the concerned laboratory.

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시기능과 조절 용이성과의 관계 연구 (The study on relation between ocular function and accommodative facility)

  • 박현주
    • 한국안광학회지
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    • 제10권4호
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    • pp.375-380
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    • 2005
  • 근거리에서 폭주와 조절 상태를 평가하기 위해 안질환이 없는 성인남녀 92명에 대해 양안 완전 교정 후 양안 균형을 취한 굴절 교정 도수를 시험테에 장용 시킨 후, 근거리(40 cm)에서 MEM 검영법 및 Bell 검영법(Welch Allyn, USA), 조절 용이성 검사(${\pm}2.00$ D Flipper, Bernell Co., USA), 버전스 용이성 검사(Prism Flipper, Bernell Co., USA)를 실시하였다. MEM 검영값은 우안과 좌안이 각각 (+)$1.05{\pm}0.87$ D, (+)$1.02{\pm}0.80$ D, BELL 검영값은 $17.89{\pm}12.12cm$, $17.94{\pm}11.72cm$, 양안 조절 용이성(적/녹)은 $7.69{\pm}6.48cpm$, 양안 조정 용이성(편광)은 $11.76{\pm}5.22cpm$, 단안 조절 용이성(우안/좌안)은 $13.9{\pm}6.27/13.8{\pm}5.96cpm$, 버전스 용이성은 $13.5{\pm}6.40cpm$로 검출되었다.

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