• 제목/요약/키워드: empirical formula

검색결과 609건 처리시간 0.03초

$CO_2$ 레이저 광의 조사 조건에 따른 치아의 치수강내 온도변화 (Temperature change in pulp chamber of teeth by $CO_2$ laser irradiation)

  • 엄효순
    • 한국광학회:학술대회논문집
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    • 한국광학회 1990년도 제5회 파동 및 레이저 학술발표회 5th Conference on Waves and lasers 논문집 - 한국광학회
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    • pp.45-48
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    • 1990
  • CO2 laser beam was focused by a ZnSe lens onto the center of the occlusal surface f extracted lower molars. K-type thermocouple was contacted with the pulp chamber and the changes of temperature in the during and after the laser irradiation were measured as function of the power of laser beam, the time of laser irradiation and thickness of the sample. An empirical formula for temperature effect was derived from the measured data.

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전단과 비틀림의 최소 철근비에 대한 이론적 접근 (Rational Approach for Minimum Shear and Torsion Reinforcement)

  • 이민섭;홍성걸
    • 한국콘크리트학회:학술대회논문집
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    • 한국콘크리트학회 1999년도 학회창립 10주년 기념 1999년도 가을 학술발표회 논문집
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    • pp.445-448
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    • 1999
  • The minimum shear and torsional reinforcement provisions in ACI 318-95 are still empirical. This paper describes the derivation of a rational approach for minimum shear and torsional reinforcement in beams so as to preclude brittle failure in shear and torsion. This is ensured by specifying that the beam's ultimate capacity of shear and torsion should be greater than its cracking shear and torsion. The formula presented herein for computing minimum shear and torsional reinforcement shows the need for modification of current provision for the minimum shear and torsion reinforcement.

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유체속에 잠긴 구주위에서의 열 및 유동특성에 관한 연구 (Study on the thermal and flow characteristics around a sphere submerged in the fluid)

  • 박희용;임경빈
    • 대한기계학회논문집
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    • 제5권3호
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    • pp.238-243
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    • 1981
  • An empirical formula for the mass flow rate in natural convection flume above a spherical heated body which is submerged in a finite fluid contained in a tank was determined. The ratio of depth of submergence to diameter of the sphere for which the sphere sensed as infinite medium was found to be bigger than 7. A dimensionless heat transfer correlation for the natural convection from a sphere was determined for Gr.Prq etween 7x10$\^$7/ and 2x10$\^$8/ also.

사용반복하중에 대한 철근콘크리트 부재의 피로거동 (Fatigue Behavior of RC Elements under High Cyclic Loading)

  • 강보순;심형섭;황성춘
    • 한국콘크리트학회:학술대회논문집
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    • 한국콘크리트학회 2001년도 가을 학술발표회 논문집
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    • pp.1161-1166
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    • 2001
  • Fatigue behavior of reinforced concrete(RC) elements has been experimentally and analytical investigated. Fatigue behavior influenced by longitudinal reinforcement ratio, strength of concrete and load ratio $P_{u}$/ $P_{o}$. The purpose of these studies is to propose an empirical formula for fatigue behavior on basis of experimental results. Also an analytical method to predict the crack propagation of RC beams has been developed based on the relationships between bond stress and slip.

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R/C 보에서 아취현상에 기초한 전단강도 산정 (A Derivation of Shear Strength Equation based on Arch Action in Reinforced Concrete Beams)

  • 김우;김대중
    • 한국콘크리트학회:학술대회논문집
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    • 한국콘크리트학회 1995년도 봄 학술발표회 논문집
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    • pp.299-304
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    • 1995
  • An equation is proposed to predict ultimate shear strength. The equatiion on ultimate shear strength, which is purely based on analytical premises, is similar form to ACI code(11-6) which is derived mainly from empirical approach. Furthermore, the strength predicted by the proposed equation show better correlation with the tested values than the values calculated by Zsutty's formula.

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SCR 발진회로의 비선형해석 (Nonlinear Analysis of SCR Oscillators)

  • 박병철
    • 대한전자공학회논문지
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    • 제11권3호
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    • pp.32-35
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    • 1974
  • SCR발진회로를 등가회로와 실험식을 이용하여 2배의 비선형미분방정식으로 해석하고, 발진회로의 상흔도와 안정성을 고찰한다. 발진파형은 고주파성분을 갖이고 있고 상황점은 궤도상에서 평형점을 향하고 있으므로 이 발진회로는 안정되고 있음을 알았다.

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사용반복하중에 대한 철근콘크리트 보의 피로거동 (Fatigue behavior of RC Beams under High Cycle Loading)

  • 강보순;황성춘
    • 한국소음진동공학회:학술대회논문집
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    • 한국소음진동공학회 2001년도 추계학술대회논문집 I
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    • pp.499-503
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    • 2001
  • Fatigue behavior of reinforced concrete (RC) elements has been experimentally and analytical investigated. Fatigue behavior influenced by longitudinal reinforcement ratio, strength of concrete and load ratio P/sub u//P/sub o/. The purpose of these studies is to propose an empirical formula for fatigue behavior on basis of experimental results. Also an analytical method to predict the crack propagation of RC beams has been developed based on the relationships between bond stress and slip.

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항공기 외부소음 예측기법의 개발 (Development of the prediction method of aircraft exterior noise)

  • 심인보;이덕주
    • 한국소음진동공학회:학술대회논문집
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    • 한국소음진동공학회 2000년도 춘계학술대회논문집
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    • pp.78-83
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    • 2000
  • Exterior noise generated by the aircraft induces a serious noise pollution near the airport. For the prediction of an exterior noise radiation of aircraft an empirical formula is employed to model the acoustic sources. It is shown that the fan/compressor noise is the most dominant part of the acoustic sources in all cases.

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선박소음 예측기술의 현황과 발전방향 (Present and Future of the Shipboard Noise Prediction)

  • 김재승
    • 한국소음진동공학회:학술대회논문집
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    • 한국소음진동공학회 2010년도 춘계학술대회 논문집
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    • pp.477-478
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    • 2010
  • It was in the mid-1980s when the shipboard noise analysis was introduced to the Korean shipbuilding industry. Since then through the continued efforts of the industries in the last decades, native computational codes dedicated to the shipboard noise prediction have been developed based on empirical formula and/or sophisticated theories such as SEA and PFM. This paper addresses some problems in dealing with predicting shipboard noise and the way how to overcome the uncertainties in the prediction.

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합성수지의 유전주파수 및 온도특성에 대한 고찰 (A Study for the Dielectric Properties Dependent on Frequency and Temperature in Polymerzed Materials)

  • 김봉흡;이준웅
    • 전기의세계
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    • 제19권5호
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    • pp.8-16
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    • 1970
  • The characteristics of dielectric absorption and dispersion in polymerized materials produced in Korea was investigated in MHz band and at several sets of temperature. For this study the theoretical basis stood on the Cole-Cole's empirical formula and it has been extended to the form convenient to investigate the observation. As the result, it has been confirmed that in most cases, two or much more sorts of dipole participate in dielectric propertics of these polymers and the materials containing aromatic molecular structure have, in general, greater loss angle than those constructed chain type molecular structure.

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