• Structural Engineering and Mechanics
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• 제50권5호
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• pp.617-633
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• 2014

Because the elevated temperature degrades the mechanical properties of materials used in containments, the global behavior of containments subjected to the internal pressure under high temperature is remarkably different from that subjected to the internal pressure only. This paper concentrates on the nonlinear finite element analyses of the nuclear power plant containment structures, and the importance for the consideration of the elevated temperature effect has been emphasized because severe accident usually accompanies internal high pressure together with a high temperature increase. In addition to the consideration of nonlinear effects in the containment structure such as the tension stiffening and bond-slip effects, the change in material properties under elevated temperature is also taken into account. This paper, accordingly, focuses on the three-dimensional nonlinear analyses with thermal effects. Upon the comparison of experiment data with numerical results for the SNL 1/4 PCCV tested by internal pressure only, three-dimensional analyses for the same structure have been performed by considering internal pressure and temperature loadings designed for two kinds of severe accidents of Saturated Station Condition (SSC) and Station Black-out Scenario (SBO). Through the difference in the structural behavior of containment structures according to the addition of temperature loading, the importance of elevated temperature effect on the ultimate resisting capacity of PCCV has been emphasized.

• 한국표면공학회지
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• 제37권1호
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• pp.40-48
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• 2004

Hardness and internal stress are very important in nickel electroforming. Nickel sulfamate bath has been widely used in electroforming because of its low internal stress and moderate hardness. Nickel sulfamate bath without chloride was chosen to investigated the effect of plating variable such as temperature, PH, current density and sodium naphthalene trisulfonate as addition agent on the hardness and internal stress. It was found that hardness increased with increasing temperature and decreasing current density and ranged from 150∼310 DPH. The hardness was highest at $55^{\circ}C$ and 10∼40 mA/$\textrm{cm}^2$. The internal stress increased with increasing current density and decreasing temperature. It was minimum at PH 3.0∼3.8. Low internal stress within $\pm$1,500 psi was obtained at both $50^{\circ}C$ and $55^{\circ}C$ in 10-20 mA/$\textrm{cm}^2$. The addition of sodium naphthalene trisulfonate was found to be effective in refine columnar grains thus resulted in decreasing internal stress, increasing hardness and improving brightness.

• 한국농공학회:학술대회논문집
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• 한국농공학회 2000년도 학술발표회 발표논문집
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• pp.321-326
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• 2000

This study was performed to analyze the variation of inside temperature of greenhouse according to shading methods. We used two shading method of external and internal method. The shading effect of external screen was superior to internal screen. Soil temperature of greenhouse without screen was higher than outside soil temperature, but the value of greenhouse with internal and external screen was lower than outside.

• 한국환경보건학회지
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• 제41권2호
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• pp.82-89
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• 2015

Objectives: This study was performed to investigate the effect of cooking time on the internal temperature and color of cutlets and the reduction of indicator organisms in cutlets by cooking. Methods: Three kinds of commercially packed frozen cutlets (pork, chicken and fish cutlets), were purchased from local markets. The cutlets were cooked in a frying pan at $180^{\circ}C$ for four minutes. Internal temperature was measured with a food thermometer. Color was measured using a Hunter spectrocolorimeter. Aerobic colony counts, coliforms, and Escherichia coli were determined according to the Food Code of Korea. Results: The internal cooked temperature of every cutlet reached over $74^{\circ}C$, the temperature considered safe, after three minutes, while external temperature reached this level in two minutes (p < 0.001). The instrumental color value as lightness (L) in the cooked cutlets significantly changed (p < 0.001) after one minute. The level of aerobic colony counts of fresh cutlets was under the specification and was reduced to one tenth its level in the cooked cutlets. Coliforms and E. coli were not detected in all samples. The internal temperature of the cutlets was significantly affected by cooking time and weight (p < 0.001). The interaction effect of time and weight was also significant (p < 0.001), and time was the more influential factor. Conclusion: The results of this study indicate that the sampled cutlets should be cooked for a minimum of three minutes or more in order to ensure food safety. The results also indicate that if consumers cease cooking based on external temperature or color, there will be a risk of inadequate cooking.

• 대한중풍순환신경학회지
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• 제9권1호
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• pp.8-13
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• 2008

Objectives : This study was to investigated the correlation between average temperature & precipitation and pattern identification of the patients with stroke. Methods : 115 stroke patients within 30days of onset were registered during the study period. Pattern identification of stroke was classified into Fire and heat, Turbid phlegm and others. We took the mean of average temperature according to pattern identification and analyzed pattern identification into two groups according to climatological normal of average temperature in Seoul. We also analyzed pattern identification into two groups according to existence of precipitation. Results : Heat and fire, and other type of pattern identification had high frequency when average temperature was higher than 12.2℃. And there was no correlation between precipitation and pattern identification of stroke.

• 설비공학논문집
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• 제25권10호
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• pp.548-554
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• 2013

A thermodynamic analysis of the R404A refrigeration system with an internal heat exchanger using R744 as a secondary refrigerant is presented in this paper to optimize the design for operating parameters of the system. The main results are summarized as follows: The COP increases with increasing subcooling and superheating degree of R404A, internal heat exchanger and compression efficiency of the R404A cycle and evaporating temperature of the R744 cycle and decreasing temperature difference of the cascade heat exchanger and condensing temperature of the R404A cycle. The mass flow ratio decreases with increasing evaporating temperature of the R744 cycle and internal heat exchanger efficiency of the R404A cycle and decreasing subcooling and superheating degree of the R744 cycle, temperature difference of the cascade heat exchanger and condensing temperature of the R404A cycle.

• 한국콘크리트학회:학술대회논문집
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• 한국콘크리트학회 2004년도 춘계 학술발표회 제16권1호
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• pp.548-551
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• 2004

The main purpose of this study is to estimate the internal temperature of RC beam under fire. For this purpose, the finite difference method was used. In the previous studies, the structural behavior of fire damaged RC beams was investigated through experiments. The result was concluded that The high temperature affects the properties of concrete such as the elastic modulus, the compressive strength. The internal temperature Estimation of the concrete is helpful for understanding the structural behavior of fire damaged RC beams. Especially, high strength concrete has more spalling than normal strength one. So, this study is performed analysis of internal temperature of RC beam considering spalling.

• 한국구조물진단유지관리공학회 논문집
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• 제15권6호
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• pp.184-194
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• 2011

이 연구에서는 콘크리트 초기재령시의 역학적 특성을 분석하고 수화반응 및 발열반응으로 인한 콘크리트 내부에서 발생하는 온도 및 상대습도의 변화에 대한 분석을 실시하고자 하였다. 세 가지의 다른 단위시멘트량을 실험변수로 하였으며, 타설 직후부터 콘크리트 내부의 온도 및 상대습도의 변화 계측하기 위하여 새로운 계측시스템을 개발하였다. 단위시멘트량에 압축, 인장 및 휨강도의 변화는 크지 않았으며, 재령 7일 이후에는 증가가 많지 않았다. 각 측정부위별 최고 온도는 타설 후 약 11시간 정도 경과시에 발생되었으며 이후 점차 온도가 낮아지다가 양생 1일 경과 후 거푸집 탈형 이후부터 온도가 하강하기 시작했다. 각 측정부위별, 온도감소 분석 결과, 콘크리트 구조물의 위치 및 노출조건에 따라 온도의 변화가 굉장히 다른 것으로 분석되었으며, 초기재령에서 콘크리트 내부의 상대습도의 변화는 수화반응에 영향을 미치는 단위시멘트량 보다는 외부에 노출된 상태가 더 큰 영향을 미칠 수 있는 것으로 분석되었다.

• 대한한방내과학회지
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• 제36권3호
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• pp.228-235
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• 2015

Objectives: The aim of this study was to find an effective medical device to detect cold sensation of hands. Methods: Patients with cold sensation of hands (N=42) were recruited in July 2013. We surveyed patients’ general characteristics, severity of cold sensation, body temperature in Nogung (PC8) and Hyeopbaek (LU4) measured with a digital thermometer, digital infrared thermal imaging, and pulse wave velocity. Results: The relation between severity of cold sensation and temperature in Nogung (PC8) and Hyeopbaek (LU4) was statistically significant. The results showed a higher correlation of severity of cold sensation with Nogung (PC9) than with Hyeopback (LU4) temperature. No other indices were statistical significant. Conclusions: Measuring the Nogung (PC9) temperature is most reasonable for assessing the severity of cold sensation of hands. To generalize this result, however, a large-scale study is warranted.

• 한국건축시공학회:학술대회논문집
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• 한국건축시공학회 2023년도 가을학술발표대회논문집
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• pp.25-26
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• 2023

The internal core material and external color of a sandwich panel have a significant impact on the performance of the sandwich panel. For use on roofs and walls, the internal core material and external color must be considered. Therefore, the surface and back side temperatures were measured for each exterior color and inner core material type. For the internal core materials, urethane foam and Expanded Poly Styrene(EPS), which are core materials mainly used in sandwich panels, were selected. As colors, black and ivory were selected according to brightness, and a total of five colors were selected: red, blue, and green, which are the three primary colors of light. As a result, there were differences in surface and temperature depending on the external color and type of internal core material. Regardless of the color, the temperature was measured lower for panels with urethane foam than for panels with an internal core of EPS. This is believed to have been influenced by the difference in thermal conductivity of urethane foam being 0.023W/(m·K) and that of EPS being 0.032W/(m·K). In addition, panels with a black exterior color were found to have higher surface and back temperatures than panels of other colors, and ivory-colored panels had lower back temperatures regardless of the core material. This is proportional to the brightness and light-absorbing characteristics.