• Proceedings of the Korean Society of Tribologists and Lubrication Engineers Conference
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• 1996.04b
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• pp.126-132
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• 1996

A laboratory scale hot strip rolling wear simulator(HRWS) was developed for the purpose of investigating the tribological phenomena occurred in production hot strip rolling mills. The HRWS' main parts are the electric heater, the mechanical descaler, tandem type 2-4Hi rolling mill stands, the cooling chamber, the tension controller and coiler. By simulating the tribelogical phenomena in rolling process at laboratory, wear patterns, cracks, cat-ear wear, black film, effect of hot rolling oil lubrication, etc. were reproduced, and discussed on the performace of simulator.

• Transactions of the Korean Society of Machine Tool Engineers
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• v.15 no.2
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• pp.59-65
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• 2006

The purposes of using cutting fluid during cutting have been cooling, lubricating, chip washing and anti-corroding. However, the present manufacturing industry restricts the use of cutting fluid because cutting fluid contains poisonous substances which are harmful to the human body. Therefore environmentally conscious machining and technology have more important position in machining process because cutting fluids have significant influence on the environment in milling process. In this study, environmentally conscious machining can be obtained by the way of selecting the optimum machinig conditon using the design of experiment. Cutting using oil-mist showed better cutting characteristics than dry, air and fluid cutting with respect to by cutting force, tool wear and surface roughness. Also, the optimum machining condition for cutting using oil-mist could be selected through Taguchi method.

• The Transactions of the Korean Institute of Electrical Engineers
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• v.38 no.7
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• pp.549-556
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• 1989

Radiation induced current of the insulating oil used for X-ray tube housing was investigated in this paper. The X-ray induced current increased in proportion to the X-ray intensity and X-ray wave length and was greatly affected by the temperature of the insulating oil and the gap length` however, the current was not varied by the amount of the X-ray absorbed. The results suggest that one must consider the following problems as important factors for X-ray machine design and normal operation: cooling system of the X-ray tube housing, X-ray intensity, increasing temperature due to continuous operation, years used, and oil exchange and management.

• Journal of the Korean Society of Manufacturing Technology Engineers
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• v.8 no.1
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• pp.89-99
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• 1999

The automatic design of shell & tube type oil cooler can be used in real industrial environments. Since the automatic design system is intended to be used in small companies, it is designed to be operated well under environments of CAD package in the personal computer. It has adopted GUI in design system, and has employed DCl language. Design parameters to be considered in the design stage of shell and tube type oil cooler are type of oil cooler, outer diameter, thickness, length of tube, tube arrangement, tube pitch, flow rate, inlet and outlet temperature, physical properties, premissive pressure loss on both sides, type of baffle plate, baffle plate cutting ratio, clearance between baffle plate outer diameter and shell inner diameter and clearance between baffle plate holes. As a result, the automatic design system of shell & tube type oil cooler is constructed by the environment of CAD software using LISP. We have built database of design data for various kinds of shell & tube type oil coolers. The automatic design system have been assessed and compared with existing specification of design. Good agreement with Handbook of heat exchanger and design dta of real industrial environments has been found.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 2006.11a
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• pp.176-177
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• 2006

Two kinds of alumina nanofluids are prepared by dispersing $Al_2O_3$ nanoparticles m transformer oil. The thermal conductivity of the nanoparticle-oil mixtures increases with particle volume fraction and thermal conductivity of the solid particle itself. The $Al_2O_3$ nanoparticles at a volume of 0.5% can increase the thermal conductivity of the transformer oil by 5.7%, and the overall heat transfer coefficient by 20%. From the natural convection test using a prototype transformer, the cooling effect of $Al_2O_3$-oil nanofluids on the heating element and oil itself is confirmed. However, excessive quantities of the surfactant have a harmful effect on viscosity, and thus it is strongly recommended to control the addition of the surfactant with great care.

• Journal of the Korean Home Economics Association
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• v.35 no.5
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• pp.239-248
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• 1997

to design nature-affinitive, reasonable and effcient thermal environment plannings and facilities, the holding patterns of heating-cooling facilities·accessory devices and residents' evaluation in Cheju Province were surveyed as well as residents' understanding for them. Major findings of this study are summarized as follows: 1) In the cooling system, the percentage of air-conditioner possessor was 19.4%, which was lower possessive rate than mainland's. The location of air-conditioner was mainly public area. That is, 55.3% of the location is livingroom, and the rest was Anbang. the general cooling accessory device was a fan. It was frequently used at the children's room and the dining room. The possessive patterns of air-conditioner depend on the characteristics of residents, such as the academic carrier and the average monthly income. Characteristics of house for air-conditioner possess depend on the location, house type, the size of floor space. 2) In the heating system, individual heating system reached to 57.3%. Heating accessory devices were oil stove and electric heating blanket. Only 32.2% of survey population were holders. 3) Residents preferred better ventilated room arrangement, which was characteristic of subtropical areas. 4) The preferred condition for heating-cooling facilities and accessory devices were strong solidity, less air pollution, and less noise.

• Journal of the Korean Society of Manufacturing Process Engineers
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• v.19 no.7
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• pp.60-66
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• 2020

In order to improve fatigue life of transmission gear carburizing is normally used. Carburizing is a very good process to achieve low cost and high performance. The machined gears are heated up to carburizing temperature and then cooled rapidly in an oil bath to produce high surface hardness. The gears may undergo excessive thermal distortion during heating and rapid cooling. In order to predict the distortion during heating and rapid cooling, a coupled thermo-mechanical simulation is needed. In the current research, the simulation of heating and cooling was performed. The results show that the thermal distortion and the residual stresses are well predicted by the coupled simulation. In addition, induction heating and rapid cooling simulation is carried out to predict the thermal distortion. The amount of distortion is compared. It is shown that induction heating is very effective to reduce thermal distortion.

• Journal of the Korean Society of Tobacco Science
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• v.25 no.2
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• pp.160-166
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• 2003

The majority of ι-menthol is still obtained by freezing the oil of Mentha arvensis to crystallize the menthol present. This 'natural' menthol is then physically seperated by centrifuging the supernatant liquid away from the menthol crystal. But the price of natural ι-menthol has fluctuated widely so effort has been devoted to the production of ι-menthol by synthetic more readily available raw materials. In the 1970's, many researcher synthesised a new compounds with the menthol cooling effect. During this period many molecular structure designed and synthesised on concepts of correlation between structure and biological activity and the various types of molecule which give rise to cooling effect more than ι-menthol. Specially, N-alkyl-carboxamide group is substituted for the hydroxyl group in ι-menthol. Recently, the most active compounds synthesised is 4-methyl-3-(1-pyrrolidinyl)-2-[5H]-furanone. This compound is 35 times more powerful in the mouth and 512 times more powerful on the skin than ι-menthol. The cooling effect also lasts twice as long. While not yet commercially available, it is expected that these types of materials will be subjected to toxicological studies and will soon be sell on the market.

• Proceedings of the SAREK Conference
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• 2008.06a
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• pp.1279-1284
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• 2008

The alternative energy has lately attracted considerable attention due to the high oil price and environment problem. Deep sea water that is one of the natural energy sources should be getting popular continually to reduce the environment problem. In this study, cooling system of deep sea water using heat exchangers of two hotels where is located in near Hae-undae Bay has been analyzed on the quantity of electricity comparison between existing cooling system and deep seawater cooling system. As shortly, the results of study showed that the first building approximately saves 370 millions won per year, also the second building saves 248 millions won per year. It means that the cooling system by using deep sea water has great worth to reduce the ratio of fossil fuel.

• Journal of Advanced Marine Engineering and Technology
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• v.31 no.5
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• pp.592-598
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• 2007

The fuel charge is getting higher in navigation cost. Therefore, shipowners try to find the method for reducing oil consumption. ESS(Energy Saving System) is one of he method. ESS is the system consisted with two inverters, ESS control unit and monitoring system. Two inverters control two main sea water cooling pumps. In the ESS control Unit, the control algorithm finds optimized point to decrease a power consumption of main sea water cooling pumps. Monitoring system observes ESS not to work improperly. ESS is experimented in the laboratory with real condition and analyzed in every view. After experiment, the result of the experiment shows that the control algorithm works correctly and safely. ESS has a plan to be operated in the ship soon. In that case, additional devices are needed to connect ESS with cooling system of the vessel. So the development of addition device is needed and being studied.