• 대한기계학회논문집
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• 제9권4호
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• pp.463-470
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• 1985

본 논문에서는 가열관을 이용한 실험과 고온표면위에 놓인 물방울의 증발실험 을 통하여 재수착온도에 미치는 영향인자들을 분석하였으며, 이러한 분석결과를 토대 로 재수착온도상관식을 제시하였다.

• 대한기계학회논문집
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• 제8권1호
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• pp.48-56
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• 1984

In order to estimate the fuel rod temperature during the reflooding phase of the PWR LOCA, it is essential to obtain a better understanding of the rewetting mechanism. This paper presents the results of analytical and experimental investigations aimed at analyzing the rewetting phenomena in a heated tube. A two-dimensional solution of the rewetting for a tube is described and used to yield the correlation of the rewetting heat transfer coefficient as the function of flooding rate and inlet subcooling. This correlation prediction is in good agreement with the experimental data.

• Nuclear Engineering and Technology
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• 제12권1호
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• pp.9-18
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• 1980

냉각재 상실사고에 따르는 rewetting현상을 연구하기 위하여 대기압에서 단일가열관을 사용한 재관수 실험을 수행하였다. Yamanouchi 이론을 바탕으로한 1차원 및 2차원 열전도 해석을 본 실험조건과 일치시키기 위해 수정하여 실험결과와 비교 검토하였다. 하부재관수 해석에서는 unrewetted 구역에서 증기의 열전달이 고려 되어야 한다는 것을 알았다. 실험을 통해 revetting속도는 시험관의 초기벽온도, 냉각재 유량, 냉각재 온도에 따라 달라진다는 것을 알았다. rewetting 온도와 열전달 계수를 평가하기 위한 보다 나은 방법의 개발이 필요하다.

• Nuclear Engineering and Technology
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• 제12권3호
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• pp.153-162
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• 1980

냉각재상실사고의 재관수 단계중 연료봉 피복재의 온도거동 및 열전달 기구를 파악하는 것은 비상노심냉각계통 및 원자로의 안전성해석에 중요하다. 냉각재유동채널의 방위가 rewetting과정에 미치는 영향을 연구하기 위하여 수직 및 수경 유동채널을 이용한 실험을 수행하였으며, 노심이 수평압력관으로 구성되어 있는 CANDU원자로에 관한 실험을 중점적으로 수행하여 그 결과를 수직채널의 결과와 비교 하였다. 또한 rewetting현상을 육안관찰가기 위해 환상형 테스트부 및 외부에서 가열되는 석영관을 사용하였다. 실험결과로써 수평채널에서의 rewetting 속도는 유동의 층상 현상에 크게 영향을 받으나 그 평균값은 수직채널리 경우와 큰차이없음을 알 수 있었다.

• Nuclear Engineering and Technology
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• 제13권1호
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• pp.12-21
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• 1981

지난번 이미 다른곳에 발표한 재침수속도공식(rewetting velocity model)에 관한 논문을 더 확충하였다. 앞서 발표한 재침수속도 공식을 사용하려면 ø의 값을 미리 알고 있어야한다. ø값을 모를 때에는 film boiling 열전달계수 ( $h_{df}$ )와 fog-film길이 (ι)의 자료가 있어야 한다. 이러한 자료를 제공하기 위해서, 먼저 브롬리(Bromley)의 공식을 수정하여 보다 높은 압력조건하에서의 $h_{df}$ 값을 구하였다. 그리고, 지난번 사용한 자료보다 훨씬 더 충실한 PWR-FLECHT 자료를 사용하여 ø와 ι과 같은 precooling 계수들의 합을 더 확충하여 놓았다. 이리하여, 재침수속도공식의 응용 가능한 영역을 더 확대하였다.

• Journal of Biosystems Engineering
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• 제12권2호
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• pp.38-43
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• 1987

An experimental study was conducted to develop a thin-layer rewetting equation of short grain rough rice of Akihikari variety. Four thin-layer rewetting equations were experimentally determined from $25^{\circ}C$ to $45^{\circ}C$ and 70%RH to 85%RH conditions. Diffusion, Henderson, Page, and Thompson equations widely used as thin-layer drying equations were selected. Experimental data were fitted to these equations using linear regression analysis except diffusion equation. The diffusivity in the diffusion equation was determined by optimization method. Four equations were highly significant. In order to compare the goodness of fit of each equation, the error mean square of each equawas calculated. The diffusion model was not a very good model because the error mean square was very large. The other three models showed the same level or error mean square and could predict satisfactorily the rewetting rate or short grain rough rice.

• Restorative Dentistry and Endodontics
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• 제29권2호
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• pp.153-161
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• 2004

This study investigated that the effect of rewetting agent on dentinal microtensile bond strength(${\mu}TBS$). Human molars were sectioned to expose the superficial dentin surfaces. Samples were divided into two groups according to type of adhesives-Single Bond (S) and One-Step (0)], and again subdivided into five groups by different dentin surface treatment-dry for 15s (D), blot dry (BD) or dry for 15s, and rewet with different rewetting agents [distilled water (DW), Gluma Desensitizer (GD) and Aqua-Prep (AP)] for 30s. After application of adhesive, composite resin was built up on the bonding surface. Each tooth was sectioned to obtain stick with $1\textrm{mm}^2$ cross sectional area and the ${\mu}TBS$ was determined by EZ test. In the S group, the mean ${\mu}TBS$ of GD, AP, and BD group was significantly higher than that of DW and D group (p < 0.05), In the O group, the mean, ${\mu}TBS$ of AP, GD, BD and DW group was significantly higher than that of D group (p < 0.05). The data suggested that Gluma Desensitizer and Aqua-Prep could be successfully used as rewetting agents, and Distilled water could be acceptable in aceton based adhesive system only.

• 대한기계학회논문집
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• 제10권1호
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• pp.7-14
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• 1986

본 연구에서는 가압경수형 원자로심을 모의하는 3*3배열로 된 모의연료 봉다발의 실험장치를 이용하여 재완수과정의 유동특성과 열전달특성을 파악하였으며, 재완수과정중 연료봉의 온도거동을 예측하는 REFLUX코드를 최근 개발된 연구자료를 토대로 수정하여 본실험결과와 비교하였다.

• 설비공학논문집
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• 제3권1호
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• pp.51-60
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• 1991

The aim of this study is to investigate the heat transfer characteristics in the transient cooling process of a high temperature wall. The slow transient cooling experiment was carried out with a copper block of high thermal capacity. The results of these experiments are as follows. 1. Temperature histories measured by the thermocouple, which is 0.99, 2.00, 2.99mm from the heat transfer surface showed monotonous during the cooling process. These variation are the curves of typical temperature histories in film-boiling, transition-boiling, and nucleate-boiling regions. 2. The temperature histories were measured by thermocouple installed in the copper block. The variations of the surface heat fluxes and surface temperature were computed from the numerical solution method TDMA from the measured temperature histories for radial position one dimensional heat transfer inverse problem. The boiling curves were found by the computed temperature histories. 3. The rewetting point which starts to change from film boiling to nucleate boiling is not connected with the mass velocity and it were found that the temperature of rewetting point indicated about $100^{\circ}C$. 4. The heat flux of rewetting point was about $10^5Kcal/m^2h$, at that time, the heat transfer coeficient indicated about $1000Kcal/m^2h^{\circ}C$ irrelevent to mass velocity. 5. The wall superheat decreases as the pressure increases. But I found that rewetting point appeared under higher condition in the wall temperature.

• 대한치과보존학회:학술대회논문집
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• 대한치과보존학회 2003년도 제120회 추계학술대회 제 5차 한ㆍ일 치과보존학회 공동학술대회
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• pp.568-568
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• 2003

I. Objectives This study investigated the effect of rewetting agent on dentinal microtensile bond strengths(${\mu}TBS$), using one bottle adhesives. II. Materials and Methods Non caries human molars were sectioned to exposed the superficial dentin surfaces, etched 15 seconds using 32% phosphoric acid and 10 seconds rinsed. Samples were randomly divided into two groups according to adhesives (Single Bond, One-Step) used. Each group were subdivided into five groups by different dentin surface treatment：15 second dry(D), blot dry(BD) or 15 second dry and rewetted with distrilled water(DW), Gluma Desensitizer(GD) and Aqua-Prep(AP) during 30 second, respectively.(omitted)