• Journal of the Korea Institute of Building Construction
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• v.3 no.2
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• pp.135-139
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• 2003

The purpose of this study is to analyze the curing effect of planar surface heater for concreting in cold weather. Some experiments were conducted to evaluate the temperature history of concrete cured with heating sheets in the laboratory conditions. As the results, It was showed that the 130W/$m^2$-heater could raise the inner temperature more than $20^{\circ}C$ under the environmental condition of -5~$-20^{\circ}C$. And the temperature of concrete cured by the 200W/$m^2$-heater was 5~$10^{\circ}C$ higher than that of concrete cured by 130W/$m^2$-heater. Finally, through the curing by the planar surface heater during the first 1.5~2 days, it is possible to secure the sufficient maturity of concrete.

• Applied Microscopy
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• v.36 no.spc1
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• pp.57-61
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• 2006

High-resolution microscopy was applied for surveying hydride stability in Vanadium alloys, which are candidate for hydrogen storage materials of advanced hydrogen energy systems. $V_2H$ hydride in V alloys was stable at room temperature under the vacuum condition, but it was decomposed during heating up to $100^{\circ}C$. It was confirmed from HRTEM image and FFT that $V_2H$ has a BCT structure, where hydrogen atoms locate at octahedral sites. Crystal orientation was <110> beta// <110> mat., and lattice strain is about 10%. After the decomposition of the hydride, relatively large lattice expansion was observed in the matrix, which suggests that hydrogen atoms should be trapped by lattice defects and included in the matrix. Intensive electron beam also enhanced the decomposition.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.58 no.1
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• pp.67-70
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• 2013

This research study was to develop methods for inhibiting the germination of cotton seeds. Germination rates after heating treatment at $80^{\circ}C$ with 10, 20, 30, 40 min. were 9.3, 9.3, 5.3 and 1.3 percentage, respectively. Heat treatment over $85^{\circ}C$ with 10 min. caused no germination of cotton seeds. Germination was significantly reduced with gamma rays treatment more than 10,000 gy, while the treatment within 2,000-8,000 gy induced less effects. Microwave processing for 30 seconds and 60 seconds inhibit the germination of cotton seed under 8 and 0%, respectively. As a physical treatment, rollmill milling with 1.5, 2, 2.5 mm gap inhibited any germination of cotton seeds. The optimum gap of roll-mill for processing physical cracking was below 51% of the thickness of seed.

• Transactions of the Korean Society of Automotive Engineers
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• v.14 no.5
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• pp.25-31
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• 2006

Controlled Auto Ignition(CAI) combustion has great potential in achieving significant increase in engine efficiency, while simultaneously reducing exhaust emissions. The process itself involves the auto ignition and subsequent simultaneous combustion of a premixed charge. In this study, NVO(Negative Valve Overlap) system was applied to a CAI engine in order to use residual gas. The fuel was injected directly to the cylinder under the high temperature condition resulting from heating the intake port to initiate CAI combustion. This paper introduced the valve timing strategy and experimental set-up. From this study, the effect of engine speed and valve timing on CAI combustion and exhaust emissions was clarified. In addition, stratified charge method was used to extend CAI operating region.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 2004.07a
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• pp.211-214
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• 2004

The advantage of ring-shaped electrodeless fluorescent lamp is the removal of internal electrodes and heating filaments that are a light-limiting factor of conventional fluorescent lamps. Therefore, the life time of ring-shaped electrodeless fluorescent lamps is substantially higher than that of conventional fluorescent lamps and last up to 60,000 hours and is intended as a high efficacy replacement for the incandescent reflector lamp in many applications. In this paper, maxwell 3D finite element analysis program(Ansoft) was used to obtain electromagnetic properties associated with the coil and nearby structures. The electromagnetic emitting properties were presented by 3D simulation software operated at 250[kHz] and some specific conditions

• 보존과학연구
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• s.23
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• pp.113-129
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• 2002

This study is to disclose the gilding technique and distinctive features of using surface improvement technique in ancient gilt. There are many kinds of the ancient gilding technique so this thesis mainly focused on mercury amalgam gilding. Gilding technique can be largely divided into two branches – the cladding and amalgam method - in ancient periods. The researches have been carried out on two parts; the first is to find the making progress of amalgam on all sort of the gilding materials and the second is to show features of the gilded layer among basic metals. As a result of this experiment, to achieve good quality of amalgam, suitable particle size of the gilding material should be needed and the heating, a primary factor, has an effect on amalgam to be formed. Aspecial features of amalgam gilding, according to changing the basicmetal, would be influenced by chemical attraction for the mercury, condition of the surface and some other factors. A platers abilities and the making progress of amalgam would be influenced by a uniform and good gilding layer. In conclusion, it should be profoundly studied and investigated on the ancient gilding techniques and gold-gilt relics.

• Korean Journal of Acupuncture
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• v.26 no.4
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• pp.145-156
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• 2009

Objective : To increase the safety of moxibustion by understanding moxibustion-prohibited points' distinguishing features through literary inquiry. Method : We searched for moxibustion-prohibited points in Traditional Oriental Medical literature. Results : 1. Upon the advancement of moxibustion technique, the numbers of moxibustion-prohibited points increased. 2. Both Foot Meridians and Hand Meridians have similar percentage of moxibustion-prohibited points. Both Yin Meridians and Yang Meridians have similar percentage of moxibustion-prohibited points. 3. The face has the highest moxibustion-prohibited points ratio. The Back has the lowest moxibustion-prohibited points ratio. 4. We research 80 moxibustion-prohibited points and find 31 moxibustion-prohibitive reasons. A key reasons is that heating effect of moxibustion damages tissues, organs and meridian functions. There are also cases where the moxibustion-prohibited points can be designated upon the patients condition Conclusions : We could learn the distinguishing characteristics of moxibustion-prohibited points from this study. These results suggest that the treatment of moxibustion is more useful and safe.

• Proceedings of the Korea Institute of Fire Science and Engineering Conference
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• 1997.11a
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• pp.85-92
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• 1997

Flammability of non-flame-retardant and flame-retardant materials was studied by using cone calorimeter Also, relations between the results obtained by using cone calorimeter and those obtained by the flammability test of japanese fire Service Law were examined. The results are as follows: 1) The ignition time of the molten specimens is relatively long, whereas the ignition time of the non-molten specimens is short. None of remarkable difference of the ignition time has been found between non-flame-retardant and flame-retardant materials specimens. 2) The peak heat release rates of flame-retardant materials are smaller than those of non-flame- retardant materials. 3) The carbon monoxide and smoke evolved from flame-retardant materials generate much more than those evolved from non-flame-retardant materials. 4) Even if flame-retardant materials are passed by the flammability test of Japanese Fire Service Law, they burn easily under external radiative heating condition.

• Journal of Life Science
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• v.12 no.3
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• pp.357-362
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• 2002

A bacterial strain showing the fibrinolytic activity was screened from korean traditional soybean products. For the identification, the strain was investigated morphology and biochemical characteristics and it was classified to Bacillus subtilis. The strain had high fibrinolytic activity in Chungkukjang. The optimum fermentation condition of temperature and time were 37$^{\circ}C$ and 24hour. The pH in Chungkukjang was gradually alkalized during fermentation. The fibrinolytic enzyme in Chungkukjang stable at heft treatment; After heating at 6$0^{\circ}C$ and 8$0^{\circ}C$ for 30 min, the fibrinolytic activity remained 75% and 40%, respectively.

• Journal of Welding and Joining
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• v.28 no.2
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• pp.60-65
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• 2010

Although two dimensional axi-symmetric modeling is useful for calculating the residual stresses of a cylindrical weldment such as a core barrel, this conventional axi-symmetric modeling can not express the behavior of shrinkage well in the locally heated weld zone. New technique of two dimensional axi-symmetric modeling using a virtual fixture is suggested to simulate the behavior of dimensional changes in the weld zone during the heating period of the welding. The virtual fixture in the model has a role to restrain the expansion of the high temperature heated region, which simulates equivalent intrinsic restraint effect of the weldment. In the restraint condition of the virtual fixture above the critical yield strength, the calculated shrinkages by using the suggested axi-symmetric model agreed well with those measured in a welded mock-up. The calculated residual stresses by using the suggested axi-symmetric model also agreed well with those calculated by using conventional axi-symmetric model which has beenused for calculating residual stresses in the weldment.