• 한국정밀공학회:학술대회논문집
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• 한국정밀공학회 2000년도 추계학술대회 논문집
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• pp.587-590
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• 2000

The new core making method economized on core sand requested. The new method is heating core box until it reaches reasonable temperature and then spraying core sand with core binder into core box. Inner temperature distribution have to uniform in order to form core of uniform thickness. Therefore, in this study we treat of inner temperature distribution of core box in priority. First, determine proper torch number. Next, optimize the torch position to minimize the average of absolute deviation(AVEDEV) of inner temperature. The results are as followed : 1. The torch number that makes inner temperature distribution about $300^\circ{C}$ uniformly is 25. 2. When $S_H$ and $S_V$ is 0.7, the torch position is optimized and AVEDEV is 5.85.

• Safety and Health at Work
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• 제13권1호
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• pp.99-103
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• 2022

Background: Firefighters may experience high environmental temperatures or carry out intensive physical tasks, or both, which leads to increased core body temperature and risk of fatalities. Hence there is a need to remotely and non-invasively monitor core body temperature. Methods: Estimated (heart rate algorithm) and actual core body temperature (ingested telemetric pill) measures were collected simultaneously for comparison during training exercises on 44 firefighter volunteers. Results: Prediction of core body temperature varied, with no specific identifiable pattern between the algorithm values and directly measured body core temperatures. Group agreement of Lin's Concordance of 0.74 (95% Upper 0.75, lower CI 0.73), was deemed poor. Conclusion: From individual agreement data Lin's Concordance was variable (Min 0.11, CI 0.13-0.01; Max 0.83, CI 0.86-0.80), indicating that the heart rate algorithm approach was not suitable for core body temperature monitoring in this population group, especially at the higher more critical core body temperatures seen.

• 한국정밀공학회지
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• 제19권1호
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• pp.43-47
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• 2002

The new core making method economizing the amount of core sand has been requested. The new method is that a core box is heated until it reaches reasonable temperature and then core sand with core binder is sprayed into the core box. Since inner temperature distribution have to be uniform in order to form uniform thickness of core, we studied inner temperature distribution of core box. First, we determined proper number of torches and optimized torch positions to minimize the average of absolute deviation(AVEDEV) of inner temperature. The results are as fellowed: 1. The number of torches that enables uniform inner temperature distribution about $300^{\circ}C$ is 25. 2. When $S_H$ and $S_V$ is 0.7, the torch positions are optimized and AVEDEV is 5.85.

• 한국세라믹학회지
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• 제34권10호
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• pp.1015-1020
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• 1997

In the Nd;YAG crystal growth by Czochralski method, the relationship between the core formation and the solid-liquid interface was observed by controlling the temperature gradient in the furnace. When the crystal was grown along<111> direction, defects and core area were reduced as the temperature gradient increased. The optimum temperature gradient was found to be higher than 4$0^{\circ}C$/cm. The Nd3+ concentration analysis by ICP-Mass showed that the segregation coefficient was about 20% higher in the core region than core-free region, where the segregation coefficients of core region and core-free region were 0.22 and 0.18, respectively.

• Nuclear Engineering and Technology
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• 제54권6호
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• pp.2048-2054
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• 2022

The coolant temperature feedback coefficient is an important parameter of reactor core power control system. To study the coolant temperature feedback coefficient influence on the core power control system of small PWR, the core power control system is built with the nonlinear model and fuzzy control theory. Then, the uncertainty quantification method of reactor core parameters is established based on the Latin hypercube sampling method and the Bootstrap method. Finally, under the conditions of reactivity step perturbation and coolant inlet temperature step perturbation, uncertainty analysis for two cases is carried out. The result shows that with fuzzy controller and fuzzy PID controller, the uncertainty of the coolant temperature feedback coefficient affects the core power control system, and the maximum uncertainties of core relative power, coolant temperature deviation, fuel temperature deviation and total reactivity are acceptable.

• Journal of Nutrition and Health
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• 제31권4호
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• pp.747-755
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• 1998

In order to study the relationship between body core temperature and adiposity , the core temperatures of normal weight female college students were measured during an instant-noodle lunch eaten in a laboratory at the ambient temperature of 22-24.8$^{\circ}C$. Ambient temperature was positively correlated with meal-start core temperature and meal duration. The difference between the peak postprandial and the meal-start core temperature was negatively correlated with body weight and BMI. This means that the thermogenic response induced by meal consumption was negatively associated with adiposity. Meal duration also showed a negative correlation with body weight, BMI, and hip girth. Thus, the obese eating style characterized by a rapid rate of food intake was also associated with adiposity in normal weight women. It was possibly a contributing factor in the development of obesity. In conclusion, adiposity is negatively associated with the difference between the peak postprandial and the meal-start core temperature and meal duration during a meal.

• 수면정신생리
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• 제23권2호
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• pp.47-52
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• 2016

Changes in core body temperature are closely related to initiation and maintenance of sleep, and are influenced by various factors such as air temperature, room temperature, clothing, human activities, and medications. These factors are closely related to sleep fragments, insomnia and other sleep disorders. Understanding the effect of the temperature related to human surroundings on the core body temperature and sleep, will be useful for understanding the physiology of sleep and to treat sleep disorders.

• 센서학회지
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• 제21권6호
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• pp.456-460
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• 2012

Au/$SnO_2$ core-shell structure nanoparticles (NPs) were synthesized by microwave hydrothermal method, and the effect of working temperature on sensitivity of Au/$SnO_2$ core-shell NPs for CO gas was investigated. The $SnO_2$ shell layer was consisted of $SnO_2$ primary particles with 4.5 nm diameter. The response of Au/$SnO_2$ core-shell NPs for CO gas was maximized at the working temperature of $350^{\circ}C$ while the sensitivity increased with decreasing the working temperature due to the low grain size effect of $SnO_2$ NPs on the response of CO gas.

• 한국결정성장학회지
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• 제30권3호
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• pp.110-116
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• 2020

MLCC(Multi-Layer Ceramic Capacitor)의 유전체 층에 사용되는 BaTiO₃ 입자는 안정한 TCC(Temperature Characteristics of Capacitance) 거동을 갖기 위해 core/shell 구조를 갖는다. 지금까지 shell의 특성은 core/shell 구조의 전체 특성에서 유추해 왔다. 이는 core/shell 구조가 겨우 수 ㎛의 작은 크기로 shell 특성만 구별해서 측정하기가 어렵기 때문이다. 본 실험에서는 micro-contact법을 이용하여 확산쌍 시편의 계면에 형성된 확대된 core/shell 구조에 Pt 전극을 증착하여 35~135℃ 에서 shell 영역의 독립적인 TCC 거동을 측정하였다. 그 결과, 65℃에서 최대 유전율 값을 갖는 완만한 피크의 확산 상전이(Diffusion Phase Transition) 거동인 core의 특성과 구별되는 거동을 관찰하였으며, 이는 core/shell 구조의 온도-유전거동을 묘사하는 모델링에서 실험 자료로 활용될 것으로 본다.

• Journal of Advanced Marine Engineering and Technology
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• 제39권6호
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• pp.604-608
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• 2015

본 연구에서는 다심관(Multi Core Tube)에 단열재로 글라스울(Glass wool)을 사용한 단열 다심관(Insulated Multi Core Tube)의 열전달 특성에 관하여 검토하였다. 제작된 단열 다심관에 대하여 외기온도, 유압 오일 공급온도, 유압 오일 공급유량에 따른 단열 다심관 내부의 유압 오일의 온도특성에 관하여 실험 및 모델링을 통하여 검토하였다. 그 결과 본 연구의 범위 내에서 최소 유압 오일 공급유량인 0.29(l/min)인 경우 실험결과와 수치해석 결과의 온도차이가 최대 약 $3^{\circ}C$정도 발생하였다. 외기온도가 일정한 경우 유압 오일 공급온도가 높을수록 유압 오일의 공급유량에 관계없이 유압 오일 출구온도가 높아지고, 유압 오일 공급유량이 1.01(l/min)이상일 경우에는 유압 오일의 온도강하에 외기온도의 영향이 적음을 알 수 있었다.