• 한국태양에너지학회 논문집
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• 제28권1호
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• pp.19-24
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• 2008

The energy crisis is culminating for the life of the fossil fuel in the future which is come to end at $30{\sim}40$ years. Moreover above 90% of the energy in our country depend on importing and the crisis is more seγious than it of other countries. So architects devote low energy house research and it means underground space research have become public opinion. But there is not an accurate and utility method calculating the heating load of underground space. In this study it is proposed that the heating load is calculated by setting adiabatic thichness of soil and predicting underground temperature. The prediction of the underground temperature is calculated by the latitude, the level, the distance from sea, the condition of earth surface.

• 한국전기전자재료학회:학술대회논문집
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• 한국전기전자재료학회 2007년도 추계학술대회 논문집
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• pp.253-254
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• 2007

In this study, in order to develop low temperature sintering multilayer piezoelectric actuator, PMN-PNN-PZT system ceramics were fabricated using $Li_2CO_3-Bi_2O_3$-CuO as sintering aids and their piezoelectric and dielectric characteristics were investigated as a function of heating rate. At sintering temperature of $900^{\circ}C$, with increasing heating rate, electromechanical coupling factor(kp), mechanical quality factor(Qm) and dielectric constant $({\varepsilon}_r)$ were increased.

• 한국의류학회지
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• 제35권3호
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• pp.292-303
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• 2011

This research suggested a draft proposal for a smart jacket design, which has applied wearable technologies to provide convenience in daily life. The smart jacket combined with a vest was the casual item for autumn and winter. The heating device was composed of the heating element, battery, controller, electric wire, connector, switch, and charger. A stable electronic conductor fiber of good heating effect with a flexible zigzag form has been selected for the heating element. The lighting device has been made in a way that attaches the LED and its power controller in the same mechanical device. As the result of the wearing test, the heating effect turned out to be effective in the order of: back, both the back and abdomen and only the abdomen. When wearing a smart jacket, the back and abdomen have been selected as favorable body parts for heating. Pockets and hems are selected as the adequate place to attach the LED lighting, and the brightness of LED lighting has turned out to be suitable and useful. Based on the test results, the first draft proposal has attached the heating element only in the back and its controller located in the inside pocket of the vest. In addition, the LED has been attached to the front pocket of the jacket. As to the second draft proposal, heating elements have been placed in the back and the abdomen. Each controller for the heating elements has been placed in the front and inside pocket of vest, and the LED lighting has been attached to the hem of the jacket. The smart jacket combined with a wearable device was assessed by functioning categories. The user showed a high satisfaction in the heating and illuminating function of a smart jacket.

• 한국인터넷방송통신학회논문지
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• 제20권6호
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• pp.65-70
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• 2020

본 논문에서는 고효율의 냉난방시스템을 구축하기 위해 냉방기와 난방기를 한 대로 동시에 할 수 있는 냉난방 동시형 멀티 에어컨 시스템을 개발하고 하이브리드형 식물공장에 적용하여 복합형 농장의 자동화가 가능하도록 하였다. 이를 위하여 난방시에 응축기 기능을 하는 열교환기가 냉방시에는 증발기 기능을 하도록 함으로써 냉난방을 동시에 구현하도록 하였다. 실험을 위하여 냉난방 동시형 멀티 에어컨시스템을 제작하고 농장의 식물공장에 적용시켜 식물의 재배 및 보관, 건조 등을 할 수 있도록 하였다. 그 결과 하나의 시스템으로 냉난방을 동시에 해결하는 에너지 절약 시스템으로 농산물의 온도환경을 조절할 수 있었으며 에어컨과 보일러를 동시에 설치하지 않아도 되는 공조시스템을 구현하여 효율적인 농작물 관리가 가능하였다.

• 한국주거학회논문집
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• 제13권5호
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• pp.89-99
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• 2002

The multifamily housing has various advantages in construction cost, land-use intensity. KRIHS(1997) recommended the proper scale of th multifamily housing as 800 households in constructability, 1,000 households in facility compactability, 500 households in social aspect. At the early planning stage of project, the size of the multiftmily housing has, until now, been maximizingly considered under the regulation on which has been emphasized at the building volume ratio, land area, etc., except for the expenditure during the maintenance stage. This paper aimed at providing the proper size of multifamily housing in aspect of area and household number with maintenance cost at the early stage of project. For these, it took 곧 average cost function which is made from the 3-rd quardratic form and analyzes the unit increasing rate of the average cost. It surveyed in nationwide focused on the central heating system using diesel and kerosene. The number of samples is 88 and items of management cost is 11. The results are as follows ; first, 3rd-order quadratic function is proper at explaining the cost variation, considering the multicollinearity and statistics. Second, the proper size of multifamily housing is recommended with 83,000 $m^2$ on management area, 820 or over the 2,630 household number in aspect of total management cost.

• 대한디지털의료영상학회논문지
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• 제12권2호
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• pp.145-150
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• 2010

Thick films of carbon fiber were prepared by a heating element of plan shape made in Darin co., We have investigated surface morphology of the specimen depending on heat-treatment temperatures. Scanning electron microscope(SEM) image of carbon fiber thick films of the specimen heat treated shows a grain growth at $1200^{\circ}C$ and becomes a poly-crystallization at $1350^{\circ}C$. The variation of resistivity at the thermally annealed specimen above $600^{\circ}C$ depends on type of the substrates. It may be due to a variation of film thickness and a difference of interfacial phenomena. A heating element of features was affected significantly by skin blood and quantity of heat of the body physiological function. After radiation of farinfrared for plate heating element, the function of biometric physiological is considered of skin blood flow and calorie which greatly affects on individuals. Electromagnetic wave was not influence on the body.

• 한국조경학회지
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• 제26권3호
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• pp.104-117
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• 1998

Rising concern about climate change has evoked interest in the potential for urban vegetation to help reduce the level of atmospheric CO\sub 2\, a major heat-trapping gas. This study quantified the functio of home energy savings and carbon emission reduction by shading, evapotranspiration and windspeed reduction of urban vegetatioin in Chuncheon. Tree and shrub cover averaged approximately 13% in residential land. The effects of shading, evapotranspiration and windspeed reduction annually saved heating energy by 2.2% and cooling energy by 8.8%. The heating and cooling energy savings reduced carbon emissions by 3.0% annually. These avoided emissions equaled the amount of carbon emitted annually from fossil fuel consumption by a population of about 1,230. Carbon emission reduction per residential building was 55kg for detached buildings and 872 kg for multifamily buildings. Urban vegetation annually decreased heating and cooling energy cost by ￦1.1 billions, which were equivalent to annual savings of ￦10,000 savings and carbon emission reduction due to tree plantings in the wrong locations, while windspeed reduction had a great effect. Plantings fo large trees close to the west and east wall of buildings, full tree plantings on the north, and avoidance of shade-tree plantings or selection of solar-friendlytrees on the south were recommended to improve the function of building energy savings and carbon emission reduction by urban vegetation.

• 설비공학논문집
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• 제27권3호
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• pp.146-151
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• 2015

The heat transfer performance of heating medium oil fluidized bed heat exchanger was measured. The operation variables were air flow rate, air inlet temperature, moisture content, water flow rate and water inlet temperature. The outside heat transfer coefficient was determined from the heat exchanger experiment and its experimental correlation was determined as a function of air velocity and viscosity of heating medium oil. Effect of viscosity was well agreed with the previous studies. Errors of the correlation equation was less than about 10% for outside heat transfer coefficient developed in this study when compared with the measured value. Hot water with the temperature greater than $77^{\circ}C$ could be produced by using the heating medium oil fluidized bed heat exchanger.

• 동력기계공학회지
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• 제20권6호
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• pp.20-26
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• 2016

For power electronic devices, the thermal energy density per unit volume has seen a rapid increase in recent years, owing to the miniaturization and dense integration of electronic components, as well as the continuous development in performance and function. This research examined the validity and reliability of a thermal safety model for managing the heating conditions of TRIAC electronic components. Among the electronic components of a PCB, these can be considered as a heat source. Using the model, the heating conditions of TRIAC components were maintained at their design target levels in the process of developing an LMT motor drive board. In addition, the heating characteristics of the entire PCB were analyzed to verify its thermal safety. Finally, the reliability and validity of the thermal safety model for maintaining the heating conditions of the TRIAC electronic elements at adequate levels was verified using a numerical analysis method.

• 설비공학논문집
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• 제15권10호
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• pp.879-887
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• 2003

Buildings with heating and cooling systems have been increased, since the requirement of thermal comfort for residents is grown. Heating and cooling systems, have been changed from two separate systems to one multi-function system which includes both heating and cooling. Especially, heat pump heating and cooling system has been adopted for general classrooms in schools since education environment improvement project has been launched. This research suggests the best option for the heat pump heating and cooling system in educational buildings through economic assessments for four alternative systems based on electric heat pump (EHP) and gas engine driven heat pump (GHP), which are most widely used for elementary, middle and high schools. The model buildings are in the Y high school which has 24 classes of new construction building, which will be built soon. Annual energy consumption for alternative systems uses BECS 3.10, which can be used for system simulation.