• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 2008.06a
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• pp.179-180
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• 2008

In this paper, we studied the optical property of transparent glasses for photovoltaic module manufacturing. The glass should have high mechanical and chemical resistance from outside environmental. Also optical transparency is a key requirement for better electrical performance. In here, we examine several kinds of transparent glasses and special purpose ones. This would give some real information for understanding PV module. The further analysis is described in the following paper.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 2008.06a
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• pp.35-36
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• 2008

In this paper, we studied the long term durability estimation for crystalline photovoltaic module while exposing to mechanical stress. Solar cell and PV module have many different kinds of stresses from cell to module fabrication. For this reason, some solar cell shows micro crack that decrease crystallization. In here, we expose artificial mechanical load on surface of PV module. Through this, the periodic external force on PV module might give an negative effect. The further analysis is described in the following paper.

• Proceedings of the SAREK Conference
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• 2007.11a
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• pp.635-639
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• 2007

In this study, optimal design and test of flat-plate heat pipe were carried out in order to improve both thermal response and surface temperature uniformity of heating plate. Experimental results show that the thermal response of flat-plate heat pipe is faster than that of a conventional heating type ones along with less weight and cost. The surface temperature uniformity is also improved.

• Proceedings of the KAIS Fall Conference
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• 2000.10a
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• pp.233-236
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• 2000

산업화에 따라 발생하는 산업폐수에는 많은 종류의 유해한 유기물들이 함유되어 있으며, 이러한 유독성 유기물을 제거하기 위하여 많은 연구가 진행되어 왔으나. 기존의 처리 방법들은 2차 환경오염을 유발한다는 문제점을 갖고 있다. 최근 폐수처리에 광촉매를 이용한 광분해 반응이 기존의 처리방법들에서 나타날 수 있는 문제점과 폐수중의 유독성 유기물을 제거할 수 있는 환경친화적 공정이라는 보고가 있은 후 광촉매에 대한 연구가 활발히 진행되고 있다. 본 연구에서는 광촉매 TiO₂의 표면특성을 XRD, SEM 및 BET를 사용하여 자세히 고찰하였다. XRD 결과 Degussa P25는 anatase 구조와 rutile 구조가 섞인 형태였으며, Aldrich Degissa TiO₂는 100% anatase 구조, KIER TiO₂는 100% rutile 구조를 가졌고 SEM 결과 Aldrich와 Degussa TiO₂의 입자형태는 작은 입자들이 뭉쳐있는 형태였으나 KIER TiO₂는 작은 입자들이 독립적으로 분리된 타원형으로 입자크기가 가장 컸다. 반면 BET 결과 Degussa TiO₂의 비표면적이 59㎡/g으로 Aldrich TiO₂(6㎡/g)나 KIER TiO₂(14 ㎡/g)에 비하여 매우 큼을 알 수 있었다.

• Proceedings of the KIPE Conference
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• 2001.07a
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• pp.128-130
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• 2001

심야전력요금제도의 정착으로 최근 심야전력축열기기의 보급이 활성화되고 있다. 그러나 모든 심야 전력축열기기들이 심야요금개시시간대인 22:00경에 동시에 가동됨에 따라 23:00에 심야전력 부하가 최대에 이르러 전력피크가 발생하여 한전의 수요관리에 큰 어려움을 주고 있다. 따라서 이 피크 부하를 심야전력 공급시간대의 저부하시간대로 분산시킬 수 있는 심야 전력축열기기 통전시간제어가 필요하게 되었다.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 2007.06a
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• pp.12-13
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• 2007

In this paper, we studied the analysis of environmental effects on maximum output power change of crystalline silicon photovoltaic module. During the test period, there was a 5% reduction of maximum output power on an average. And the degree of output power uniformity became better compared to initial value. Using climate data like rain, snow and dust, we tried to find the reasons for maximum power fluctuation. The surface of PV module was monitored using microscope and infrared camera to study temperature distribution. The further analysis is described in the following paper.

• 한국신재생에너지학회:학술대회논문집
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• 2006.06a
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• pp.323-324
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• 2006

In the present paper a forecasting system of wind power generation for Walryong Site, Jejudo is presented, which has been developed and evaluated as a first step toward establishing Korea Forecasting Model of Wind Power Generation. The forecasting model, KIER forecaster is constructed based on statistical models and is trained with wind speed data observed at Gosan Weather Station nearby Walryong Si to. Due to short period of measurements at Walryong Site for training statistical model, Gosan wind data were substituted and transplanted to Walryong Site by using Measure-Correlate-Predict technique. Three-hour advanced forecast ins shows good agreement with the measurement at Walryong site with the correlation factor 0.88 and MAE(mean absolute error) 15% under.

• Proceedings of the SAREK Conference
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• 2006.06a
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• pp.203-208
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• 2006

The unutilized energy in urban area is commercially and environmentally worth recycling since it can be used as a good energy resource for the heating and cooling supply. Therefore, once heating and cooling demands are near the available unutilized energy resources, a high performance district heating and cooling can be realized by the network of unutilized energy technology. In relation to this circumstance, a road map of the unutilized energy technology is presented in this study.

• Proceedings of the SAREK Conference
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• 2006.06a
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• pp.982-987
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• 2006

The fluid mechanics and heat transfer of surfactant turbulent pipe flows are characterized with particular emphasis on the effects of surfactant concentration and solution temperature on drag reduction and heat transfer reduction. The test fluids are the surfactant solutions of DR-IW616 supplied by Akzo Nobel Chemical in concentration of $100{\sim}3000ppm$. The solution temperatures studied are $5^{\circ}C$ to $50^{\circ}C$. The critical values of surfactant concentration and solution temperature are clearly identified for drag reduction phenomena.

• Korean Chemical Engineering Research
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• v.54 no.4
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• pp.533-542
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• 2016

We investigate fluidization characteristics of the mixture of rice husk, silica sand and rice husk ash as a preliminary study for valuable utilization of rice husk ash obtained from gasification of rice husk in a fluidized bed reactor. As experiment valuables, the blending ratio of rice husk and sand (rice husk: sand) is selected as 5:95, 10:90, 20:80 and 30:70 on a volume base. Rice husk ash was added with 6 vol% of rice husk for each experiment and air velocity to the reactor was 0~0.63 m/s. In both rice husk/sand and rice husk/sand/ash mixture, the minimum fluidization velocity (Umf) is observed as 0.19~0.21 m/s at feeding of 0~10 vol.% of rice husk and 0.30 m/s at feeding of 20 vol.% of rice husk. With increasing the amount of rice husk up to 30 vol.%, $U_{mf}$ can not measure due to segregation behavior. The mixing index for each experiment is determined using mixing index equation proposed by Brereton and Grace. The mixing index of the mixture of rice husk/sand and rice husk/sand/ash was 0.8~1 and 0.88~1, respectively. The optimum fluidization condition was found for the good mixing and separation of rice husk ash.