• 대한전기학회:학술대회논문집
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• 대한전기학회 1987년도 전기.전자공학 학술대회 논문집(II)
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• pp.1292-1295
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• 1987

In noninvasive temperature measurement within body, this paper is presented temperature measurement method in security and with effect from Applicator by electromagnetic, and it is analyzed heat generation quantity or temperature rise distribution by computer simulation within body. In this paper, two-dimensional model is considered and temperature distribution produced by RF capacitive heating system is analyzed by using Finit Element Method (F.E.M). A passibility of temperature distribution control is examined based on the position and size of Applicator.

• Computers and Concrete
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• 제13권1호
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• pp.97-115
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• 2014

Silica fume is a by-product of induction arc furnaces and has long been used as a mineral admixture to produce high-strength, high-performance concrete. Due to the pozzolanic reaction between calcium hydroxide and silica fume, compared with that of Portland cement, the hydration of concrete containing silica fume is much more complex. In this paper, by considering the production of calcium hydroxide in cement hydration and its consumption in the pozzolanic reaction, a numerical model is proposed to simulate the hydration of concrete containing silica fume. The heat evolution rate of silica fume concrete is determined from the contribution of cement hydration and the pozzolanic reaction. Furthermore, the temperature distribution and temperature history in hardening blended concrete are evaluated based on the degree of hydration of the cement and the mineral admixtures. The proposed model is verified through experimental data on concrete with different water-to-cement ratios and mineral admixture substitution ratios.

• 수산해양기술연구
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• 제33권3호
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• pp.209-217
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• 1997

The objective of this paper is to improve a discomfort caused by the unequal airflow and vertical temperature difference by buoyancy of the supplied hot air in the conventional hot air heating system. In order to the model experiment we manufactured the hot air heater with two air outlet and a model room. We observed the temperature, velocity and airflow distribution and calculated values of PMV and PPD using mean value of central verticality section's air temperature and velocity. We could improve distribution of vertical temperature and velocity at the central section of the model room owing to correlation of hot air of two air outlet.

• 대한기계학회:학술대회논문집
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• 대한기계학회 2008년도 추계학술대회B
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• pp.2334-2339
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• 2008

This paper proposes an improved mathematical model for predicting the frosting behavior on a two-dimensional fin considering the heat conduction of heat exchanger fins under frosting conditions. The model consists of laminar flow equation in airflow, diffusion equation of water vapor for frost layer, and heat conduction equation in fin, and these are coupled together. In this model, the change in three-dimensional airside airflow caused by frost growth is accounted for. The fin surface temperature increased toward the fin tip due to the fin heat conduction. On the contrary, the temperature gradient in the airflow direction(x-dir.) is small throughout the entire fin. The frost thickness in the direction perpendicular to airflow, i.e. z-dir., decreases exponentially toward the fin tip due to non-uniform temperature distribution. The rate of decrease of heat transfer in the airflow direction is high compared to that in the z-direction due to more decrease in the sensible and latent heat rate in x-direction.

• 산업경영시스템학회지
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• 제21권46호
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• pp.159-166
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• 1998

Estimating the temperature distribution of a refrigerator-room is important for preventing the over-refrigeration and improving its operating efficiency. It is also necessary in the realization process of the concentrated refrigeration function which has been provided recently as a generalized function in many refrigerator models. In this paper, we investigate the estimation problem of temperature in refrigerator-room and propose a fuzzy adaptive model. The model is unique in that it employs the concept of the fuzzy dead zone in order to improve the accuracy of estimation. The obtained results are then used for determining the optimal position of a temperature sensor.

• 한국신뢰성학회지:신뢰성응용연구
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• 제13권1호
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• pp.65-76
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• 2013

In order to assess the reliability of engine mount for a vehicles, life test model and procedure are developed. By using this method, failure mechanism and life distribution are analyzed. The main results are as follows; i) the main failure mechanism is degradation failure of engine mount rubber by fatigue failure at dynamic load. ii) temperature is a second factor to affect a failure. iii) the life distribution of engine mount module is fitted well to Weibull life distribution and the shape parameter is 18.4 and the accelerated life model of that is fitted well to Arrhenius model.

• 한국자동차공학회논문집
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• 제22권1호
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• pp.117-125
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• 2014

The temperature distribution of steady state rolling tires with detailed tread blocks is numerically predicted using the three dimensional full patterned tire model. A three dimensional periodic patterned tire model is constructed by copying 1-sector mesh in the circumferential direction. Using the static tire contact analysis, the strain cycles during one revolution are approximated with the strains at Guassian points of the elements which are sector-wise repeated within the same circular ring of elements, by neglecting the tire rolling effect. Based upon the multi-axial fatigue theory, the maximum principal strain is used to represent the combined effect of six strain components on the hysteretic loss. In the following, the deformation due to the inflation and vertical load is calculated using ABAQUS. Then heat generation rate in each element is calculated using an in-house code. Lastly, temperature distribution is calculated using ABAQUS again. Through the numerical experiments, the validity of the proposed prediction method is examined by comparing with the experiment and the temperature distribution of a patterned tire model is compared with those of the main-grooved simple tire model.

• 제어로봇시스템학회논문지
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• 제5권4호
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• pp.481-488
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• 1999

A thermal model based on the chamber geometry of the industry-standard AST SHS200MA rapid thermal processing system has been developed for the study of thermal uniformity and process repeatability thermal model combines radiation energy transfer directly from the tungsten-halogen lamps and the steady-state thermal conducting equations. Because of the difficulties of solving partial differential equation, calculation of wafer temperature was performed by using finite-difference approximation. The proposed thermal model was verified via titanium silicidation experiments. As a result, we can conclude that the thermal model show good estimation of wafer surface temperature distribution.

• 대한기계학회논문집
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• 제15권6호
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• pp.2100-2108
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• 1991

본 연구에서는 최근 한국동력자원연구소에서 개발한 로타리 킬른형의 도시 쓰 레기 소각로에 대하여 전열해석한 것으로 이 해석을 통하여 소각로에서의 쓰레기, 배 기가스 그리고 로벽에서의 온도 분포를 예측할 수 있다.

• 전기학회논문지
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• 제68권1호
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• pp.52-60
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• 2019

In this paper, four types of insulation coils were fabricated by adding various kinds of glycols to improve the flexibility and adhesion of insulating coils in varnish dispersed with PAI / Nano Silica_15wt%. The applied voltage and frequency were 1.5 kV / 20 kHz for accelerated life evaluation. Through the 6th temperature stress level, the cause of the insulation breakdown of the coil was ignored and only the breakdown time was measured. The Arrhenius model was chosen based on the theoretical relationship between chemical reaction rate and temperature for estimating the insulation life of the coil due to accelerated thermal stress. Three types of distributions (Weibull, Lognormal, Exponential) were selected as the relationship between thermal stress model and distribution. The average insulation lifetime was estimated under the temperature stress of four types of insulation coils through the relationship between one kind of model and three kinds of distributions.