• Korean Journal of Air-Conditioning and Refrigeration Engineering
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• v.29 no.7
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• pp.373-384
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• 2017

The objective of this study was to determine the effect of refrigerant heat exchanger on the performance of type II absorption heat pump performance using numerical analysis. Two heat exchange installation methods were used: solution to refrigerant and waste hot water to refrigerant. These methods were compared to the standard model of hot water flow without using refrigerant heat exchanger. When waste hot waters were bypassed to refrigerant heat exchanger, COP was not affected. However, steam mass generation rates were increased compared to those of the standard model. When solutions were bypassed to the refrigerant heat exchanger, results were different depending on the place where the solution rejoined. COP and steam mass generation rates were lower compared to those when waste heat water was passed to refrigerant heat exchanger. Thus, it is possible to obtain higher steam mass generation rates by using waste water and installing refrigerant heat exchanger.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 1997.04a
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• pp.160-163
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• 1997

The object of this study is to develop various composing material for SOFC generation system, and to test unit cell performance manufactured. So we try to present a guidance for developing mass power generation system. We concentrated on development of manufacturing process for cathode, anode and electrolyte.

• Proceedings of the Korea Institute of Applied Superconductivity and Cryogenics Conference
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• 1999.02a
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• pp.165-168
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• 1999

Thermodynamic cycle analysis has been performed for the power generation systems to utilize the cold energy of liquefied natural gas (LNG). Among many possible configurations of the cycle, the open Rankine cycle, the closed Rankine cycle, and the closed Brayton cycle are selecte for the analysis because of their practical importance. The power output per unit mass of LNG has been analytically calculated for various design parameters. The optimal conditions for the parameters to maximize the power output are presented and some of the design considerations are discussed.

• Proceedings of the KIEE Conference
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• 1997.07d
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• pp.1389-1390
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• 1997

The object of this research is to develop various composing material for Solid Oxide Fuel Cell generation system, and to test single cell performance manufactured. So we try to present a guidance for developing mass power generation system. We concentrated on development of manufacturing process for cathode, anode and electrolyte.

• Journal of applied mathematics & informatics
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• v.9 no.2
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• pp.731-744
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• 2002

The temperature distribution in human skin and subdermal tissue layer is presented using bioheat transfer equation. The body temperature is determined by the balance between heat produced and heat lost by our body. The time-dependent solutions have been found to be affected by the metabolic heat generation rate, blood mass flow, the rate of evaporation of perspiration and also by the atmospheric temperature. The analytic solutions for different layers have been calculated numerically and are also shown graphically.

• Bulletin of the Korean Chemical Society
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• v.35 no.11
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• pp.3363-3365
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• 2014

• The Bulletin of The Korean Astronomical Society
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• v.39 no.2
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• pp.118.1-118.1
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• 2014

Stars create and expel new chemical elements and dust at the end of the stellar life cycle. Therefore, understanding the evolved stars, their mass loss process, and the conditions of the returning material to be mixed with the surrounding interstellar medium is an important step toward studies on the new generation of stars as well as the evolution of cosmic elements in galactic scale. I will review the first results from the ALMA Early Science on the evolved stars and direct future works.

• Journal of Welding and Joining
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• v.20 no.3
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• pp.46-53
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• 2002

The expolitation of substitute material and new manufacturing technology of the automobile body panel for next generation cars have been steadily professed by advanced automobile companies. High strength steel of TRIP (Transformation of Induced Plasticity) type is developed in response to demands about crash safety and high strength of automobile. In this study, basic technologies can fix up problems occurring on the mass production and applied to the other forming methods will be prepared through rasping a property of TRIP material.

• Transactions of the Korean Society of Mechanical Engineers A
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• v.27 no.10
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• pp.1661-1666
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• 2003

The purpose of this study is to develop the simplified model of the crankshaft in the large marine engine for dynamic analysis. Because the actual engine system is under complex dynamic loading condition and it has multi-cylinder, the dynamic analysis is purchased at a high computation cost. In spite of this burden, the dynamic analysis must be perfonned to assure structural integrity of operating marine engine. Therefore, simplification of the analytic model is necessary for dynamic analysis. Beam-mass model, which is generated with the section property method, is the model simplified effectively. Section property method can provide desired section information by optimization technique. By applying beam-mass model to the crankshaft in the large marine engine, the usefulness of the proposed method was proven.

• Journal of the Korean Society for Industrial and Applied Mathematics
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• v.20 no.4
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• pp.355-374
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• 2016

This work is devoted to investigate heat and mass transfer effects on MHD natural convection flow past an inclined plate with ramped temperature numerically. The dimensionless governing equations for this investigation are solved by using finite element method. The effects of angle inclination, buoyancy ratio parameter, permeability parameter, magnetic parameter, Prandtl number, heat generation, thermal radiation, Eckert number, Schmidt number, chemical reaction parameter and time on velocity, temperature and concentration fields are studied and presented with the aid of figures. The effects of the pertinent parameters on skin friction, rate of heat transfer and mass transfer coefficients are presented in tabular form. The numerical results are compared graphically with previously published result as special case of the present investigation and results found to be in good agreement.