• Title/Summary/Keyword: 온도경계조건

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Design of Temperature Regulation for DNA Kernel to Satisfy Positive Definiteness (DNA 커널이 양한정 조건을 만족시키기 위한 온도 조절 디자인)

  • Noh, Yung-Kyun;Kim, Cheong-Tak;Zhang, Byoung-Tak
    • Proceedings of the Korean Information Science Society Conference
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    • 2007.06b
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    • pp.15-20
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    • 2007
  • 기존의 연구는 DNA 커널을 통한 기계 학습이 DNA 분자들을 통한 in vitro 실험을 통해 가능함을 보였다. 이 때, DNA 커널을 통한 분류 분제는 온도 조절을 통해 양한정(positive definite) 조건을 만족시킬 때 분류 문제를 잘 풀며, 양한정 조건을 만족시키기 위한 조건으로 높은 온도에서 시작하여 온도를 내리며 hybridization시키는 방법을 제안하였다. 이 논문에서는 보다 정량적인 분석을 통해서 이 hybridization 방법이 양한정 조건을 만족시키기에 적합한 방법임을 보이고, 간단한 hybridization 모델을 통해 양한정 조건을 만족시킬 수 있는 hybridization 온도 계획의 충분 조건을 유도한다. 또한 시작 온도와 끝 온도의 경계 조건으로 제시되는 이 충분 조건을 통해 현실적인 온도 조절 계획을 위한 시퀀스의 코딩 방법을 알게 된다.

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Analysis of Temperature Distribution of Solid and Gas in the Rotary Cooler (회전냉각기에서 고체와 가스의 온도분포해석)

  • 이만승;최주석;전철근
    • Resources Recycling
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    • v.11 no.3
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    • pp.25-30
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    • 2002
  • Heat transfer occurring in the rotary cooler was analyzed by applying a one-dimensional steady state. The temperature of inlet gas and the measured temperature of outlet gas were used as boundary conditions. Axial temperature distribution of solid, gas and wall were calculated by solving two differential equations and two algebraic equations under the constraint of two point boundary conditions and operating conditions. The temperatures of outer wall calculated in this study were in good agreement with those measured from running rotary cooler.

Finite Element Analysis of Temperature Distribution for Power Transformer (유한요소법을 이용한 전력용변압기의 온도분포해석)

  • Ahn, Hyun-Mo;Hahn, Sung-Chin
    • Proceedings of the KIEE Conference
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    • 2009.07a
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    • pp.818_819
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    • 2009
  • 본 논문에서는 온도상승의 열원이 되는 권선과 철심의 전력손실을 유한요소법을 이용한 전자계해석과 스타인메츠실험식으로 산정하였다. 온도에 대한 자연대류 열전달계수를 산정하여 경계면에서의 경계조건으로 적용하였다. 열전달 해석을 위해 전력용변압기를 3차원 형상으로 모델링한 후 유한요소법을 이용해 권선과 철심에서의 온도분포를 해석하였다.

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Detection of Cavities by Inverse Heat Conduction Boundary Element Method Using Minimal Energy Technique (최소 에너지기법을 이용한 역 열전도 경계요소법의 공동 탐지)

  • Choi, C.Y.
    • Journal of the Korean Society for Nondestructive Testing
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    • v.17 no.4
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    • pp.237-247
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    • 1997
  • A geometrical inverse heat conduction problem is solved for the infrared scanning cavity detection by the boundary element method using minimal energy technique. By minimizing the kinetic energy of temperature field, boundary element equations are converted to the quadratic programming problem. A hypothetical inner boundary is defined such that the actual cavity is located interior to the domain. Temperatures at hypothetical inner boundary are determined to meet the constraints of mea- surement error of surface temperature obtained by infrared scanning, and then boundary element analysis is peformed for the position of an unknown boundary (cavity). Cavity detection algorithm is provided, and the effects of minimal energy technique on the inverse solution method are investigated by means of numerical analysis.

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Linear Stability of Variable-Viscosity Fluid Layer under Convection Boundary Condition (대류 조건하의 가변 점성 유체층의 선형 안전성)

  • 송태호
    • Transactions of the Korean Society of Mechanical Engineers
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    • v.16 no.1
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    • pp.132-141
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    • 1992
  • The critical condition for onset of Benard convection with variable viscosity .nu.=.nu.$_{0}$exp(-CT) has been obtained using a linear stability theory. The bottom wall is rigid while the upper surface may be either free or rigid. The two boundaries are subject to convective heat transfer. The critical Rayleigh numbers are presented up to maximum viscosity ratio of 3000. It is greater for smaller upper and/or lower surface Biot numbers. Its dependence on the viscosity ratio is complicated. However, a simple sublayer theory is found to be applicable for extremely large viscosity ratio. In such cases, the critical Rayleigh number and the critical wave number are functions of viscosity ratio and lower surface Biot number.r.

The Daytime PBL Heating Process and Heating Rate by Meso-Scale Circulation (중규모 순환에 의한 대기경계층 가열과정과 주간 가열율 산정에 관한 연구)

  • 이화운;정우식;김동혁
    • Proceedings of the Korea Air Pollution Research Association Conference
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    • 2003.11a
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    • pp.441-442
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    • 2003
  • 복잡한 지형에서 국지적인 순환에 의한 에너지 교환은 기상변화에 중요한 역할을 담당한다. 종관장이 영향이 약하고 양호한 기상조건 하에서 대기 경계층내에서의 온도와 바람장은 국지적인 순환에 영향을 받는다(Kawamura,1979; Kuwagata et al.,1990; Winston et al.,1992). 즉 이러한 기상 조건 하에서는 중규모 순환에 의해 에너지의 수송효과가 크고 각기 수송된 에너지에 의해서 지역별로 대기 경계층내의 가열율에도 차이가 나타난다. (중략)

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A Study on the Boundary Condition for Analysis of Bio-heat Equation According to Light Irradiation (광조사에 따른 생체열 방정식의 해석을 위한 경계조건의 확립에 대한 연구)

  • Ko, Dong Guk;Bae, Sung Woo;Im, Ik-Tae
    • Transactions of the Korean Society of Mechanical Engineers B
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    • v.39 no.11
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    • pp.853-859
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    • 2015
  • In this study, the temperature change in an imitational biological tissue, when its surface is irradiated with bio-light, was measured by experiments. Using the experimental data, an equation for temperature as a function of time was developed in order to use it as a boundary condition in numerical studies for the model. The temperature profile was measured along the depth for several wavelengths and distances of the light source from the tissue. It was found that the temperature of the tissue increased with increasing wavelength and irradiation time; however, the difference in the temperatures with red light and near infrared light was not large. The numerical analysis results obtained by using the developed equation as boundary condition show good agreement with the measured temperatures.

Measuring Convective Heat Transfer Coefficient of Nanofluids Considering Effect of Film Temperature Change over Heated Fine Wire (막온도 변화를 고려한 가는 열선주위 나노유체의 대류열전달계수 측정 실험)

  • Lee, Shinpyo
    • Transactions of the Korean Society of Mechanical Engineers B
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    • v.37 no.8
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    • pp.725-732
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    • 2013
  • This study examined the convective heat transfer characteristics of nanofluids flowing over a heated fine wire. Convective heat transfer coefficients were measured for four different nano-engine-oil samples under three different temperature boundary conditions, i.e., both or either variation of wire and fluid temperature and constant film temperature. Experimental investigations that the increase in the convective heat transfer coefficients of nanofluids in the internal pipe flow often exceeded the increase in thermal conductivity were recently published; however, the current study did not confirm these results. Analyzing the behavior of the convective heat transfer coefficient under various temperature conditions was a useful tool to explain the relation between the thermal conductivity and the boundary layer thickness of nanofluids.

A Study on the Unsteady Temperature Characteristics at the Refrigerator Gasket Region (냉장고 가스켓 주위의 시간에 따른 온도변동 특성에 관한 연구)

  • Ha, Ji Soo
    • Journal of Energy Engineering
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    • v.21 no.2
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    • pp.138-143
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    • 2012
  • The present study has been carried out to elucidate the unsteady temperature characteristics of a refrigerator near gasket region by measuring time dependent temperature measurements. From the measured values of the time dependent temperature inside and outside region of a refrigerator, one could see that the temperature varies periodically with time from the effect of refrigerator operation. The measured mean temperatures at the wall had great different value from the previous other research results conducted by numeric ofheat transfer using improperfheat transfer boundary condition. The present study could give the experiment ofdata for the properfnumeric ofheat transfer an oysis and suggest more accuratefheat transfer boundary conditions for the inside and outside of a refrigerator.

Relationship between temperature profiles and bit size during thermomagnetic recording of amorphous TbFe thin film (비정질 TbFe박막의 열자기 기록시 온도분포와 Bit크기의 관계)

  • 이세광;박종철
    • Electrical & Electronic Materials
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    • v.3 no.3
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    • pp.187-194
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    • 1990
  • 광자기 메모리용 재료인 비정질 TbFe 박막을 대상으로 열자기 기록시 박막에 분포하는 온도와 이때 만들어지는 bit의 크기간에 상호관련성을 조사하였다. 레이저 조사에 의해 가열된 박막의 온도분포는 유한요소법을 이용한 열전달 해석에 의해 계산하였다. 레이저 가열종료 직전 박막 면에 분포하는 온도 contour로 부터 bit 크기를 예측하였다. 여기서 bit 크기는 온도 상승에 따라 보자력이 약화되어 외부자계와 박막반자장의 합력이 역자구를 만들어 준다고 가정하여 이 경계가 되는 온도(Tcrit)로 이루어지는 등온선의 크기로부터 정하였다. 열자기 기록 실험으로부터 기록 bit의 크기(Dmeas.)을 측정하여 레이저조사조건별로 예측한 bit크기(Dpred.)와 비교하였다. 특히, 레이저 pulse시간 변화에 따른 여러온도의 등온선 contour 직경변화를 조사하여 실측한 bit크기와 비교 검토함으로써 bit형성에 미치는 온도분포의 영향을 조사하였다. 이 결과 레이저 pulse시간이 길어지거나 레이저 power가 상대적으로 작을때 실측한 bit크기가 예측된 bit크기보다 커지는 것으로 나타났으며 이는 Tcrit 온도구배가 완만해질수록 bit경계가 되는 온도가 낮아지는 것으로 해석된다.

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