• The Bulletin of The Korean Astronomical Society
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• v.16
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• pp.3.1-3.1
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• 1991

• Journal of the Korea Concrete Institute
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• v.28 no.4
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• pp.395-405
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• 2016

The thermal and mechanical properties of fiber-reinforced mortars for thermal energy storage were investigated in this paper. The effect of the combination of different cementitious composite on the thermal and mechanical characteristics of fiber-reinforced mortars was investigated. Experiments were performed to measure mechanical properties including compressive strength before and after thermal cycling and split tensile strength, and to measure thermal properties including thermal conductivity and specific heat. The results showed that the residual compressive strength of mixtures with OPC and graphite was greatest among the mixtures. Thermal conductivity of mixtures with alumina cement was greater than that of mixtures with OPC, indicating favor of alumina cement for charging and discharging in thermal energy storage system. The addition of zirconium into alumina cement increased specific heat of mixtures. Test results of this study could be used to provide information of material properties for thermal energy storage concrete.

• Journal of the Korean Recycled Construction Resources Institute
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• v.3 no.3
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• pp.199-205
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• 2015

The mechanical and thermal properties of high temperature aluminate cementitious thermal storage materials were investigated in this paper. Alumina cement was used as basic binder and the effect of the replacement of fly ash, silica fume, calcium sulfo-aluminate and graphite for alumina cement was investigated. Experiments were performed to measure mechanical properties including compressive strength before and after thermal cycling, and split tensile strength, and to measure thermal properties including thermal conductivity and specific heat. Test results show that the residual compressive strengths of mixtures with alumina cement only, or alumina cement and silica fume were greater than those of the others. Additionally, the specific heat of mixture with graphite was largest in all the mixtures used in the study. The results of this study could be used to provide realistic information for material properties in thermal energy storage concrete in the future.

• Journal of Korea Foresty Energy
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• v.21 no.2
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• pp.62-68
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• 2002

Adiabatic property of plywood wall panel was examined to evaluate their thermal conductivities. The amount of heat loss was investigated through overall heat transmission experiment. Styroform and grass wool showed less heat loss. However, yellowsoil board and laminated lumber showed high volume specific heat capacity. When the changes of indoor and outdoor temperature were checked in model house, wall manufactured with styroform and grass wool was affected easily by the changes of outdoor temperature. Yellowsoil, the mixed board of yellowsoil and sawdust, and laminated lumber, which have high volume specific heat capacity, were not affected much. The rates of overall heat transmission were much better in styroform and grasswool, but the adiabatic properties were much higher in yellowsoil board and the mixed board of yellowsoil and sawdust. The results showed that the insulating material can be developed using yellowsoil and wood, which are nature friendly materials.

• Korean Journal of Optics and Photonics
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• v.26 no.4
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• pp.187-194
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• 2015

A system of infrared camera optics with wide field of view and anamorphic lenses is proposed, and its validity verified through manufacture. The infrared camera produced provides a wide field of view of over 100 degrees in the horizontal direction, and an even greater magnification in the vertical direction. As a result, the system can have a wider surveillance range and improved detection ability at the same time. In addition, a new optomechanical automatic athermalization mechanism is proposed and applied to the infrared camera. Its performance and utility is proved through testing.

• Food Science and Preservation
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• v.14 no.5
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• pp.557-563
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• 2007

This study was investigated quality characteristics of alcohol fermentation broths and by-produce produced from 4 type of brown rice varieties. The result showed that Daeanbyeo(A), Baekjinju(B) and Sulkyeong(C) produced the high alcohol content(9.5, 9.7 and 9.8%) by non-steamed alcohol fermentation period whereas the Goami(D) gave poor content(3.5%). In addition, the effect of total free sugar content were examined for non-steamed alcohol fermentation period. Among these 4 type, 244.2 mg% showed the highest contents in the Goami(D). The steamed alcohol fermentation showed higher sugar content in overall with slight difference between the various brown rice. The total dietary fiber content variation according to the alcohol fermentation methods in non-steamed and steamed periods came up with the highest content in the Sulkyeong(C) fellowed by Baekjinju(B), Daeanbyeo(A), and Goami(D). The total free amino acid content by alcohol fermentation methods timed out to show the highest content in non-steamed Goami by-product followed by Goami powder steamed Goami by-product Although, the above result revealed the lowest alcohol fermentation efficiency in non-steamed Goami, but it had the highest by-product utilizing capacity. Therefore, Goami(D) was the lowest alcohol yield in alcohol fermentation treated with non-steam among groups, but Goami by-products of the Goami had the various nutritional constitutes including starch, dietary fibers and free amino acids, which can be suggested to be used as various functional food ingredient.

• Proceedings of the Korean Magnestics Society Conference
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• 1991.05a
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• pp.13-14
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• 1991

• Journal of Korea Far Infrared Association
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• s.5
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• pp.17-24
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• 2000

• Bulletin of the Korean Space Science Society
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• 2000.04a
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• pp.19-19
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• 2000

• The Optical Journal
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• s.170
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• pp.28-32
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• 2017