• Journal of the Korean Society of Safety
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• v.11 no.2
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• pp.96-101
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• 1996

The effects of coal type and mixing fraction of coal on attrition and elutriation were studied in a 15. 5cm diameter fluidized bed coal combustor. The domestic low-grade anthracite coal with heating value 2010kcal/kg and the imported bituminous coal from Australia with heating value of 6520kcal/kg were used as coal sample. It was found from the experimental that the elutriation rate inclosed with an increseing anthracite mixing fraction. The size of elutriated particle had a very wide distribution was found in this experiment. The mean size of elutriated particle increased with decreaseing anthracite mixing fraction.

• Korean Journal of Air-Conditioning and Refrigeration Engineering
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• v.25 no.1
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• pp.1-6
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• 2013

This study aims to reduce cooling energy by grasping kinds of heating load in building in order to decrease cooling energy in summer and eliminate efficiently heating load. Lighting heating value was confirmed through examination and experiment concerning lighting heating and reducible exhaustion value was extracted lighting apparatus. The optimal exhaust system by air conditioning type was suggested for applying lighting heat exhaust system and the method contributing to promotion supplying low energy architecture was suggested by predicting reduced cooling load.

• Journal of the Korean housing association
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• v.17 no.4
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• pp.101-109
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• 2006

The purpose of this study was to suggest ways on reducing the cooling and heating energy cost of the officetel building with the multiple glazing windows according to Life Cycle Costing. This study consisted of an hour-by hour energy simulation program and further data from the EnergyPlus V1-2-2 to the four pane type windows that were applied with 2 low-e polyester film and krypton gas to the officetel model building. It was determined that the four panes type windows that had 2 low-e polyester film and krypton gas applied to, them showed a cooling and heating cost reduction over traditional double glazed windows that were filled with air. According to this study, as well as the information from chart 4.5 and the LCC it was determined that the present value of the four panes of windows that had 2 low-e polyester film and krypton gas applied to them showed. a 11.4% reduction in heating and cooling in comparison to the traditional double glazed windows that were filled with air.

• Journal of the Korea Institute of Building Construction
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• v.18 no.5
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• pp.463-469
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• 2018

A currently used roof green system with multi layers has a low constructability. Therefore a new integrated waterproof & root barrier sheet and roof green box unit system was developed using steel plate fixture and cone type fixture by electromagnetic induction heating method. This study was proceeded to evaluate adhesion performance of two types of fixtures on Engineering PE, TPO, PVC sheet in a normal condition, repeated heating and cooling condition. As a result, adhesion load on Engineering PE sheet showed the highest value. The adhesion loads of steel plate fixture showed higher value as heating temperature was getting higher. However adhesion loads of cone type fixture showed opposite tendency. Regarding to the test conditions, test results of normal condition, repeated heating and cooling condition showed same value. The cone type fixture using butyl tape showed 7 times lower adhesion load than that of cone type fixture using electromagnetic heating and 28% lower adhesion load in a repeated heating and cooling condition than a usual condition.

• Resources Recycling
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• v.23 no.5
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• pp.28-35
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• 2014

The basic properties of cow and chicken manure such as proximate analysis and element analysis were estimated and the comparison to energy characteristics of carbonization residue between cow and chicken manure was evaluated. The optimum carbonization condition of cow and chicken manure was decided by total heating value of carbonization residue which was expressed by multiplying low heating value by yield. The optimum carbonization conditions for carbonization time and temperature can be decided by 15 min, and $350^{\circ}C$ for chicken manure, and 20 min, and $300^{\circ}C$ for cow manure. At the optimum carbonization conditions, low heating values for the carbonization residue of cow and chicken manure are evaluated by 4,378kcal/kg, and 3,462kcal/kg, respectively. The residues of cow manure were satisfied with the standard of solid fuel product. However, the residue of chicken should be improved by materials changes to be used as a renewable energy source.

• Journal of the Korean Solar Energy Society
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• v.31 no.6
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• pp.95-102
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• 2011

The purpose of study is to estimate heating, cooling load performance and economic efficiency in office building with applied the functional paint. this paint can reduced SHGC(Solar Heat Gain Coefficient) on the glazing surface by coating. In this study, estimated to compared with double glazing, low-e glazing, IP(Insulation Paint) and IPu(Insulation UV-Cut Paint) coating glazing. As a result of this study, 1)heating & cooling load Analysis, SHGC value and U-factor of double glazing is about 0.70 and 3.29($W/m^2K$). low-E glazing is about 0.65 and 2.70($W/m^2K$). Two-side it is about 0.27 and 3.25($W/m^2K$). When compared to double glazing, annual heating & cooling load of low-E glazing, Two-side IPu and IP paint coating glazing is 3,012MWh($124kWh/m^2$), 2,910MWh($120kWh/m^2$), 2,867MWh($118.4kWh/m^2$) and 2,867MWh($118.4kWh/m^2$). It i sreduced to 2.0%, 5.2%, 6.7%, and 6.7% respectively. 2)the estimation of economic efficiency, low-e glazing installed in office building can not recover the investment within a lifetime 40years. but IPu and IP paint, two-side coating in glazing, have a payback period of 13 years respectively.

• Journal of the Semiconductor & Display Technology
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• v.3 no.4
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• pp.29-32
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• 2004

Fully depleted Silicon-on-Insulator (FD-SOI) devices lead to better electrical characteristics than bulk CMOS devices. However, the presence of a thin top silicon layer and a buried SiO2 layer causes self-heating due to the low thermal conductivity of the buried oxide. The electrical characteristics of FDSOI devices strongly depend on the path of heat dissipation. In this paper, we present a new three-dimensional (3-D) analysis technique for the self-heating effect of the finger-type and bar-type transistors. The 3-D analysis results show that the drain current of the finger-type transistor is 14.7% smaller than that of the bar-type transistor due to the 3-D self-heating effect. We have learned that the rate of current degradation increases significantly when the width of a transistor is smaller that a critical value in a finger-type layout. The current degradation fro the 3-D structures of the finger-type and bar-type transistors is investigated and the design issues are also discussed.

• Korean Journal of Air-Conditioning and Refrigeration Engineering
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• v.9 no.3
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• pp.300-311
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• 1997

A theoretical method was developed to analyze the effect of low-$\varepsilon$ coatings which have influence on thermal performance of vacuum windwo glazing and double pane glazing. The overall heat transfer coefficient(U) value and thermal performance were analyzed by theroretical method on various kins of windows. TRNSYS program was used to analyze total heating and cooling energy consumption on the model building which has various windows. As the result, better thermal insulation can be achieved on the vacuum window glazing than double pane glazing when low-$\varepsilon$ coating was done on the surface of glass. Total heating and cooling energy consumption was almost same on the double pane window glazing but was lessened on the vacuum window glazing when the window size of south direction increased. Therefore, low-$\varepsilon$ coating was very necessary for vacuum window glazing in order to improve thermal insulation performance and efficient energy conservation can be achieved by vacuum window glazing at the real building which has large window.

• Applied Chemistry for Engineering
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• v.23 no.5
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• pp.440-444
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• 2012

In this work, a semi-carbonized wood chip (SC-WC) was prepared by heat-treatment at low carbonization temperature. The pyrolysis characterization and heating value of the SC-WC at different heat-treatment temperature were evaluated. The pyrolysis characterization and heating value of the SC-WC were determined using thermal gravimetric analyzer (TGA) in $N_{2}$ atmosphere and calorimeter, respectively. From the TGA results, the thermal decomposition reaction of the SC-WC treated at by low temperature was similar to pure wood chip and the reaction was most actively occurred in the range of $200^{\circ}C$ to $400^{\circ}C$, whereas the initial thermal decomposition temperature of the SC-WC increased with the increasing heat-treatment temperature. In addition, the heating value of the SC-WC showed a similar trend as to the decamposition temperature behavior. This is probably attributed to increased carbon content of SC-WC by the localized carbonization of the wood chip which consisted of cellulose, hemi-cellulose, and lignin.

• 한국신재생에너지학회:학술대회논문집
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• 2007.06a
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• pp.800-803
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• 2007

Gasification has been regarded as a core technology in dealing with environmental pollutants and in obtaining higher efficiency for power generation. Among several ways in utilizing produced syngas from gasification, power generation would be the most prominent application. Syngas from coal was applied to the readily available LPG engine from automobiles. Main purpose was to identify the combustion characteristics in the modified gas engine when using syngas of low heating value and to test the modification optionsin the LPG gas engine. Gas engine rpm and the corresponding flue gas composition were measured for each syngas input condition. Results showed that even with syngas at the heating value of $1300{\sim}1800$ kcal/$Nm^3$ corresponding to the $6{\sim}7%$ of LPG heating value, gas engine operated successfully only with the problems of high CO and oxygen concentrations in the flue gas.