• Journal of Mechanical Science and Technology
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• 제16권10호
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• pp.1320-1326
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• 2002

In a one-dimensional heat conduction domain with heated and insulated walls, an integral approach is proposed to estimate time-dependent boundary heat flux without internal measurements. It is assumed that the expression of the heat flux is not known a priori. Hence, the present inverse heat conduction problem is classified as a function estimation problem. The spatial temperature distribution is approximated as a third-order polynomial of position, whose four coefficients are determined from the heat fluxes and the temperatures at both ends at each measurement. After integrating the heat conduction equation over spatial and time domain, respectively, a simple and non-iterative recursive equation to estimate the time-dependent boundary heat flux is derived. Several examples are introduced to show the effectiveness of the present approach.

• 대한한방소아과학회지
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• 제19권2호
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• pp.229-241
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• 2005

Objective : This study was designed to investigate causes, symptoms and treatments for the diabetes insipidus with oriental medical literatures. Methods : We surveyed the oriental and western medical books from to recent published bocks that have articles on diabetes insipidus Results and Conclusions : The symptoms of diabetes insipidus are polyuria and polydipsia, these are similar symptoms of Pae-so(肺消), Gouk-so, So-gal(消渴), Sang-so(上消), Sin-so(腎消), So-sin(消腎), Ha-so(下消) and Sin-jung(腎中) of kinds of So-gal(消渴) in the oriental medicine. The major causes of diabetes insipidus are the deficiency of the yin of the kidney, the heat of the heart and the dryness of the pulmonary. The methods of treatment are tonifying the yin of the kidney(滋補腎陰), tonifying qi and arrest discharges(益氣固澁), removing heat to moisten dryness (淸熱潤燥) and promoting fluid production to quench thirst(生津止葛). The herbal-medications for treatment are So-galbang and Yidongtang(消渴方合二冬湯), Ryoumijihawangtang gamibang(六味地黃湯加味方).

• 열처리공학회지
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• 제5권1호
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• pp.23-31
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• 1992

It is investigated that Fe-C-N compound layer, defusion layer, and induction hardened layer produced by nitrocarburizing blend heat treatment in austenitic temperature with high frequency induction heating of mild steel specimen sprayed sursulf salt-bath. As the temperature of blend-heat treatment got increased, the thickness and hardness of compound layer and diffusion layer were increased. Compound layer(max. $35{\mu}m$), diffusion layer (max. 2.5mm) and induction hardened layer were gained in the shortest time 10 sec and in the case of $1000^{\circ}C$ total hardness depth of those was about 3.5mm. When the blend-heat treated specimen was reheated, maximum hardness of compound layer was dropped more than that of the reheated compound layer after sursulf treated, whereas hardness of diffusion layer was increased.

• 연구논문집
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• 통권22호
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• pp.97-105
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• 1992

This study aimed to develop the heat treating equipment which could produce austenitic stainless steel welded pipes & tubes maintaining its peculiar brightness even after heat treatment. The results of this study are as follows:- Development of 8.5kHz, 150kw bright annealing system was achieved. - Bright annealing of austenitic stainless steel welded pipes & tubes was performed by the developed pilot-system through this study and heat-treatment effects were quite successful in viewpoint of surface brightness, hardness distribution, microstructure, removal of residual stress, strength and corrosion resistance.

• International Journal of Air-Conditioning and Refrigeration
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• 제13권3호
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• pp.128-137
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• 2005

In this study, dry and wet surface pressure drop and heat transfer characteristics of heat exchangers having plain fins were investigated. Nine samples having different fin pitches and rows were tested. The wet surface heat transfer coefficient was reduced from experimental data using enthalpy-potential method. The wet surface heat transfer coefficients were approximately equal to the dry surface values except for one row configuration. For one row configuration, the wet surface heat transfer coefficients were approximately $30\%$ lower than the dry surface values. For the pressure drop, the wet surface yielded approximately $30\%$ higher values compared with the dry surface counterpart. Data were compared with existing correlations.

• 한국정밀공학회:학술대회논문집
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• 한국정밀공학회 2006년도 추계학술대회 논문집
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• pp.349-350
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• 2006

• 한국초전도학회:학술대회논문집
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• 한국초전도학회 2008년도 High Temperature Superconductivity Vol.XVIII
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• pp.7-7
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• 2008

• 대한기계학회논문집B
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• 제25권9호
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• pp.1149-1156
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• 2001

The objective of the present study is to investigate the performance of electronic scale mitigation unit(ESMU), which reduces the amount of scale in a heat exchanger. The circular tube with diameter of 19mm and plate-and-frame heat exchangers with 20 thermal plates were used for the tests. In order to accelerate the rate of scale in a laboratory test, artificial hard water of 1000ppm(as CaCO$_3$) was recirculated at a flow rate of 5 lpm, 7 lpm, and 9 lpm throughout the tests. The effect of ESMU on the scale thickness and overall heat transfer coefficients was examined. The test results showed that the ESMU could reduce the scale deposits even in the acceleated test.

• 대한전기학회:학술대회논문집
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• 대한전기학회 2008년도 제39회 하계학술대회
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• pp.522-523
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• 2008

This paper develops optimal operation mechanism of CHP(Combine Heat and Power) for enhancement of energy efficiency. It verify optimal operation of Accumulator using Economic Heat Load Dispatch and Dynamic Programing through case study.

• 대한기계학회논문집B
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• 제25권9호
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• pp.1237-1244
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• 2001

An experimental study was carried out to identify the various regimes of natural convective pool boiling and to determine the boiling heat transfer curve and Critical Heat Flux(CHF) on a vertical square surface having a 70mm width and a 70mm height. The heater made of copper block with embedded cartridge heaters is submerged in a water tank at atmospheric pressure. As the heat flux increases from 100kW/㎡ to 1.2MW/㎡, the heat transfer regime migrates from the nucleate boiling to the film boiling. The boiling heat transfer data are fitted by Rohsenow type correlation. An explosive vapor generation on the heated surface, whose size and frequency are characterized by the heat flux, is visualized using a high speed digital imaging system.