• Korean Journal of Air-Conditioning and Refrigeration Engineering
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• v.26 no.2
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• pp.79-85
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• 2014

In general, building energy performance is evaluated with a detailed transient building energy simulation program. However, energy evaluation tools with the bin method are still used, because of their simple and easy way to calculate building energy performance, without reducing their precision. In this research, several heating and cooling degree day methods are compared, and evaluated with their performance for variable base temperature. This analysis considered about ten years of the continuous outdoor temperature, in the Seoul and Busan areas. It is concluded that the simplified bin method is more or less acceptable for Seoul and Busan, compared with the detailed hourly bin method.

• KIEAE Journal
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• v.13 no.3
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• pp.15-20
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• 2013

The purpose of this study is to analyze the planning characteristics of passive house by the building structural types in foreign cases. The interests and demands about passive house have been increased, and various building structural types and design methods have been attempted for passive house in Korea. But domestic research results and development experiences about passive house were lack. The results of this study are as follows; First, in terms of energy performance, insulation performance, airtightness, there are not significant differences at the 95% confidence level by the structural types of passive house. Second, in terms of the types of insulation materials, there are significant differences at the 95% confidence level by the structural types of passive house. Third, in principle there is no need of traditional heating facility in passive houses, but in practice traditional heating facilities are used additionally in about half of survey cases for the comfort of occupants.

• Tribology and Lubricants
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• v.13 no.3
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• pp.20-27
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• 1997

The tribological behavior for $MoS_2$ bonded films is evaluated according to the international standard testing methods, such as ASTM D 2625 (Falex tester) and ASTM D 2714 (LFW1 tester). It has been well known that the tribological behavior for $MoS_2$ bonded films is affected by several factors. However, in this work, the wear life for $MoS_2$ bonded films is mainly experimentally measured with different contact geometry, and evaluated in terms of the frictional heating according to the contact geometry of tribotester. The test results show that the wear life of $MoS_2$ bonded films is significantly affected not only by the frictional heating, but also by the contact pressure, test running-in conditions, and the contact conformity.

• Journal of the Korean Society for Precision Engineering
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• v.20 no.3
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• pp.125-132
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• 2003

The joint method and characteristics of MC nylon and metal are analyzed. Considering the productivity and economics, two materials are joined with the process of turning, knurling, and induction heating. The joint strength is determined by adhesion of the melted nylon, the size of knurl, and the interference from the difference of the diameters. The adhesion strength of the melted nylon is measured. The effects of the knurl size and diameter difference are analyzed with the statistical methods. Finally the joint strength is analyzed in the environments of low, room, and high temperature. Based on this study, the nylon/metal material is expected to be widely used as the sliding machine elements with good lubrication and strength properties.

• Journal of Aerospace System Engineering
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• v.15 no.6
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• pp.1-9
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• 2021

In this study, a new design of an extension-type actuator (ExACT) is proposed based on a chevron structure with displacement amplification mechanisms by local heating. ExACT comprises diamond-shaped displacement amplification structures (DASs) containing axially oriented V-shaped chevron beams, a support bar that restricts lateral heat deformation, and a loading slot for thin-film heaters. On heating the thin film heater, the diamond-shaped DASs undergo thermal expansion. However, lateral expansion is restricted by the support bar, leading to displacement amplification in the axial direction. The performance parameters of ExACT such as temperature distribution and extended displacement is calculated using thermo-mechanical analysis methods with the finite element method (FEM) tool. Subsequently, the ExACTs are fabricated using a polymer-based 3D printer capable of reproducing complex structures, and the performance of ExACTs is evaluated under various temperature conditions. Finally, the performance evaluation results were compared with those of the FEM analysis.

• Journal of the Korean Wood Science and Technology
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• v.36 no.1
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• pp.21-29
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• 2008

The deterioration of Korean traditional wooden house located in seoul was estimated. This house was attacked by termite. To estimate damage status of buildings, non-destructive methods were applied. Some of the post needed to be replaced due to low strength, estimated by nondestructive methods. The house was installed with boiler heating facility, to use office and public education. This kind of heating system changed the environmental condition of the wooden house. The termite which attacked the house was classified as Reticulitermes speratus. Because of durability of wooden house effected by environment, control of the environmental condition is essential for maintaining the wooden house. The installation of modern facility to traditional wooden house should not change the traditional structure and do not effect to durability of wooden house.

• Journal of the Korean Society of Food Science and Nutrition
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• v.41 no.7
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• pp.914-920
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• 2012

We investigated the effects of heat treatment and extraction method on the antioxidant activities of five medicinal plants: Cyperus rotundus, Eucommia ulmoides, Bupleurum falcatum, Achyranthes japonica Nakai, and Akebia quinata. Extraction was performed with only ultrasound, ultrasound after heating at $130^{\circ}C$ for 2 hours, and reflux extraction with distilled water. The phenolic contents of reflux extraction and ultrasound extraction after heating were higher than only ultrasound extraction, and ultrasound extraction after heating samples was higher than reflux extraction except for Eucommia ulmoides and Cyperus rotundus. Total flavonoid content was higher in reflux and ultrasound extraction after heating samples than only ultrasound extraction, except for Cyperus rotundus. ABTS radical scavenging activity was higher in reflux extraction and ultrasound extraction after heating a sample, than only ultrasound extraction. DPPH radical scavenging activity was higher in reflux extraction except for Achyranthes japonica Nakai and Akebia quinata. The reducing power of ultrasound extraction after heating was higher with Achyranthes japonica Nakai. From the results of this study, we can expect to increase the antioxidant activity of medicinal plant extracts by applying suitable extraction and pretreatment conditions on the type of medicinal plant.

• Korean Journal of Environmental Agriculture
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• v.2 no.2
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• pp.114-119
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• 1983

Several supplementary heating methods were investigated to find their effects on night air temperature, injury in plant, growth and yield with Hokowase strawberry(Fragaria grandiflora) under greenhouse, during early spring season in 1981 and 1982. Kerosene lamp as a supplementary heating was not suitable because of its severe injury on strawberry plants, danger of accidental fire and bad smell. Paraffine candle and electric wire heating did not injure on strawberry plant, raised the minimum air temperature in greenhouse at night, enhanced growth, flowering and harvesting time of strawberry. Paraffine candle was effective as a supplementary heating method for short period growing under greenhouse, whereas electric wire heating was suitable for long period cultivation.

• Journal of the Korean Chemical Society
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• v.53 no.5
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• pp.553-559
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• 2009

One of zeolitic imidazolate framework materials (ZIF), ZIF-8, has been synthesized with microwave irradiation and conventional electric heating at $140{\sim}180^{\circ}C}$. ZIFs are porous crystalline materials and are similar to metal organic framework (MOF) materials because both ZIFs and MOFs are composed of both organic and metallic components. ZIFs are very stable and similar to zeolites because ZIFs have tetrahedral networks. ZIF-8, with a decreased crystal size, can be synthesized rapidly with microwave irradiation. The microwave synthesis of ZIF-8 is completed in 4 h at $140{^{\circ}C}$ and the reaction time is decreased by about 5 times compared with the conventional electric heating. The ZIF-8 obtained by microwave heating has larger surface area and micropore volume compared with the ZIF-8 synthesized with conventional electric heating. It can be confirmed that ZIF-8s show type-I adsorption isotherms, explaining the microporosity of the ZIF-8s. Based on FTIR and TGA results, it can be understood that the ZIF-8s have similar bonding and thermal characteristics irrespective of heating methods such as microwave and conventional heating.

• The Korea Journal of Herbology
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• v.32 no.3
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• pp.19-27
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• 2017

Objectives : The aim of this study was to examine effect of anti-oxidant and anti-inflammation activity of the Kyeongok-go with various processing methods that was manufactured by heating mantle. Methods : Commercial Kyeongok-go (K0) was purchased and Kyeongok-go with ginseng (K1), Kyeongok-go with black ginseng (BK), ginseng fermentation Kyeongok-go (KF), black ginseng fermentation Kyeongok-go (BKF) were manufactured by heating mantle. To examine anti-oxidant effect, DPPH radical and production of NO and ROS in RAW 264.74 cell were used. Furthermore, to determined anti-inflammation effect, measured pro-inflammatory mRNA such as NOS-II, COX-2, $IL-1{\beta}$, IL-6, $TNF-{\alpha}$ in RAW 264.74 cell treated with K0, K1, KF, BK, and BKF. Result : K1 scavenged DPPH radical effectively than K0. The most DPPH radical scavenging activity was BKF. In the RAW 264.74 cells stimulated with LPS, NO and ROS production were measured. As a results, K1 was decreased NO, ROS production compared with K0, and BKF was reduced similarly to cyclosporine A (positive control). Expression of pro-inflammatory mRNA such as NOS-II, COX-2, $IL-1{\beta}$, IL-6 showed a significant decrease in BK or BKF. But, there was no significant in expression of $TNF-{\alpha}$ in all extract treatmetn groups. Conclusions : According to the above results, it is considered that Kyeongok-go with fermented black ginseng (BKF) manufactured by heating mantle is effective material that have anti-inflammation and anti-oxidant activities. Our finding indicate that BKF may be an effective agent for anti-inflammation through anti-oxidant effect.