• Journal of the Korean Solar Energy Society
• /
• v.35 no.5
• /
• pp.39-48
• /
• 2015

In this study, the solar chimney, one of the passive solar systems, is proposed as a method to improve the thermal environment of northern zones in buildings. As this well-known system has rarely been used in building projects, an adequate application of the system is proposed in this paper: the solar chimney system is designed to meet the required ventilation rate and consequently to reduce the ventilation load in the northern part of a building. To investigate such a possibility, a numerical model for the system is developed, and results of numerical tests are used for energy simulations. The results were taken into account for test simulations in EnergyPlus. As a result, approximately 75% of the volumetric ventilation rate required in the north zone could be supplied with the air volume acquired through the system and the monthly mean load was reduced by 29.5%, from 1.584 kWh to 1.117 kWh. The analyses of hourly mean heating and ventilation load over the heating period indicated that the system was very effective at around 13:00. Results show that 33% reduction in the ventilation load and 17% in the heating load for the north zone could be acquired through this system.

• Journal of the Korean Chemical Society
• /
• v.26 no.2
• /
• pp.88-94
• /
• 1982

The concentrations of gaseous ammonia and particulate ammonium emitted from a urea plan were measured, and the conversion rate of ammonia to ammonium was estimated. The conversion of ammonia to ammonium has two stages with transport time in the atmosphere. In the initial 15min the conversion rate was 3.2% min$^{-1}$, and thereafter 0.26% min$^{-1}$. The high conversion rate of ammonia to ammonium at the initial period of it's transport might be due to the dissolution of ammonia into water droplets formed by the decrease in temperature of the stack effluent. The concentration of ammonium is further increased by the decomposition of urea in alkaline droplet formed. Half-lives of ammonia gas at initial and latter slag were 16 min and 192 min respectively. No correlation of particulate ammonium concentration to temperature, relative humidity, and concentrations of sulfur dioxide, nitrogen oxides and airborne particulate matter were found in this field measurement.

• Journal of the Korean Solar Energy Society
• /
• v.22 no.3
• /
• pp.39-46
• /
• 2002

The results of experiment on the performance of natural ventilation by insulation thickness and height system of solar chimney are described. The 3-inside wall was made of concrete and 1-wall was made of glass. The two kinds of model experiment were performed. One was the varition of the 60cm, 90cm and 120cm of solar chimney, the other was the variation of the insulation thickness 10mm and 50mm and without insulation of outside wall of solar cimney. As the temperature difference between bottom and top expressed $1.7\sim2.9^{\circ}C$, air velocity measured $0.5\sim0.8m/s$ and ventilation rate was $194.4m^3/h$ in the case of the 120cm height of solar chimney, the respect of natural ventilation performance was superior to others cases in the first model experiment. Though the case of 120cm height of solar chimney was attached 50mm insulation the ventilation rate was not so much as the case of solar chimney was attached 10mm insulation. the temperature difference between bottom and top was the largest in the other cases. From this research, the natural ventilation performance of solar chimney was affected by not only height and insulation thickness of solar chimney but also wind velocity and directon.

• Analytical Science and Technology
• /
• v.20 no.1
• /
• pp.10-16
• /
• 2007

This research was designed to investigate the formations of hazardous air pollutants in the MSWs pyrolysis-gasification-melting process. In this survey, PCDDs/PCDFs (polychlorinated dibenzo-p-dioxins and polychlorinated dibenzofuran) were investigated in the two facilities (A and B facilities). In A facility, the PCDDs/DFs concentrations were 0.88, 2.29, 0.16 ng I-TEQ/$m^3$ respectively on the secondary incinerator, boiler and stack. In B facility, the PCDDs/PCDFs concentrations were 0.22, 0.05 ng I-TEQ/$m^3$ respectively on the pyrolysis-gasification-melting furnace and stack. The concentrations of PCDDs/PCDFs increased due to resynthesis during cooling process in the both facilities. High concentrations of PCDDs/PCDFs isomers were founded as 2, 3, 4, 7, 8-PeCDF, 2, 3, 4, 6, 7, 8-HxCDF and 1, 2, 3, 6, 7, 8-HxCDF orderly in A facility, and 2, 3, 4, 7, 8-PeCDF, 1, 2, 3, 7, 8-PeCDD and 2, 3, 4, 6, 7, 8-HxCDF orderly in B facility.

• Proceedings of the Korea Air Pollution Research Association Conference
• /
• 2003.05b
• /
• pp.57-58
• /
• 2003

대기중 입자상 물질은 대기중에서 발견될 수는 고체 및 액체상 물질로서 여러 가지 형태를 띄고 있다. 이러한 입자상 물질은 다양한 배출원인 자동차, 공장굴뚝, 가정난방 등과 같은 화석연료 연소시설과 토양 도로먼지, 건설현장, 해염입자 등과 같은 비 연소시설에서 배출되어 직접적으로 대기중으로 유입되기도 하며, 대기중 기체상 물질들이 태양광선 및 수증기의 존재하에서 화학반응을 일으켜 생성되는 이차입자도 있다. 미국 EPA (Environmental Production Agency)에서는 대기중 입자상 물질을 입경에 따라 두가지 형태인 PM$_{2.5}$와 PM$_{10}$으로 분류하였다. (중략)략)

• Proceedings of the Korean Radioactive Waste Society Conference
• /
• 2004.06a
• /
• pp.377-385
• /
• 2004

The quantity of radioactive waste generated from HANARO operation for the years of 1996 to 2003 has been analysed. It was found that the solid waste of $72, 999{\ell}$ and liquid waste of $263, 576{\ell}$ have been generated for the past 8 years. The amounts of Ar-41, I-131 and H-3 exhausted to the environment were 1, 225.6 Ci, 1.612E-2 Ci and 210 Ci, respectively.

• Proceedings of the KIEE Conference
• /
• 2009.07a
• /
• pp.529_530
• /
• 2009

전통적인 굴뚝산업으로 대표되는 전력산업에서 경쟁과 효율에 입각한 시장경제 지향의 전력산업구조를 선택하게 되는 배경에는 디지털경제 시대의 도래에 따른 정보통신기술의 비약적인 발전과 인터넷을 이용한 e-Business가 전력거래 업무의 주된 흐름으로 정착되고, 효율적인 발전기술의 등장으로 전력산업에 경쟁적인 거래구조의 도입이 가능하기 때문이다. 본 연구에서는 전기에너지 전자상거래를 위한 통합된 포탈시스템(e-Marketplace)의 구축으로 전기에너지 전자상거래(e-Business)의 주요 기능에 부합되는 전력공급입찰, 전력시장가격 조회, 전력거래대금 청구 및 대금결제 서비스를 종합적으로 제공하는 전력거래 e-Marketplace를 구현할 수 있음을 제시하였으며, 전력거래 업무현장에 전기에너지 전자상거래(e-Business) 비즈니스 모델을 적용함으로써 e-비즈니스 전략에 맞는 인프라와 프로세스를 확보할 수 있고, e-비즈니스 추진결과에 따른 전력거래 고객만족도 향상, 비용절감 등 부가가치 증진 요소가 지속적으로 발견될 수 있음을 제시하였다.

• Journal of the Korean Solar Energy Society
• /
• v.21 no.2
• /
• pp.35-43
• /
• 2001

The results of numerical simulation on the performance of a solar chimney system in building are described. The inside surface temperature of four walls within the solar chimney arc calculated with solar radiation and outdoor temperature in summer. The air within the solar chimney is heated by conduction, convection and radiation. Air temperature distribution from the bottom to the top and outlet air temperature can be obtained by solving energy balance equation. Since the buoyance or stack effect is affected by temperature difference between the bottom and the top within the solar chimney. It is evaluated using inlet and outlet temperatures. It is expected that natural ventilation by the solar chimney of witch the height is 7.8m and the cross sectional area is $4.93m^2$ can provide about $6400m^3/h$ on sunny day.

• Proceedings of the Korean Environmental Sciences Society Conference
• /
• 2006.05a
• /
• pp.103-104
• /
• 2006

고체연료 성상별 연소시 굴뚝에서 배출되는 입자상물질의 농도는 섬유류(86.8mg/m$^3$) > PP 마대류(26.51mg/m$^3$) > 합성수지류(16.71mg/m$^3$) > 우레탄(11.17mg/m$^3$) > 목재류(10.92mg/m$^3$) > 종이류(2.61mg/m$^3$)의 순으로 나타났다. 특히 폐섬유 소각시 입자상물질 중 중금속 함유농도는 Pb의 경우 기타 고체연료 연소시 함유농도비가 0.4% 이하인 반면에 폐섬유 소각시 6.6%인 5.72mg/m$^3$로 높게 나타났으며, Cd 또한 1.4%인 1.24mg/m$^3$로 높게 나타났다.

• Proceedings of the Korean Society for Noise and Vibration Engineering Conference
• /
• 1993.04a
• /
• pp.153-173
• /
• 1993

폭약은 탄광에서 석탄이나 각종 광물을 캐거나, 건설토목현장에서 암반 제거를 위해서 주로 사용되었다. 전쟁에서 군사용으로 파괴를 위한 목적으로 사용되기도 하였으나, 최근의 동서화해 분위기와 남북통일이 무르익는 시대적 조류로 볼때 더이상 파괴용으로의 사용은 제어될 것이고 이제는 평화를 위하여, 건설을 위하여, 산업발전을 위하여 더 많이 사용되어지고 응용되어질 것이다. 작금의 첨단산업의 발달과 산업의 고도화로 우리 화약 업계에도 첨단발파기술의 개발에 많은 관심과 연구.개발을 진행중이다. 첨단발파기술의 응용사례를 소개하면, 건축토목 분야에서 노후 고층빌딩 및 굴뚝의 철거, 노후 교량 및 공장시설의 철거등에 활용되고 있으며, 위락서비스 분야에서 응용으로는 불꽃놀이를 들 수 있다. 최근에는 첨단 과학 장비를 이용하여 각종 꽃불의 모양이 음악과 미술등 예술적인 기능을 기억시킨 컴퓨터를 활용하여 보다 고차원의 공예술품(공학-예술)을 만들어낸다. 아울러 각종 기공식 발파시에도 예술적 기능과 웅장함을 가미하여 그 화려함을 극치에 다다르게 한다. 그외에도 로켓트 발사추진제등의 우주 개발에의 응용, 석유시추등 해양개발에의 응용, 각종 공학 실험연구에의 응용, 폭발 가공에의 응용, 의학에의 응용, 철강산업에의 응용 등으로 그 숫자를 이제는 일일이 나열하기 힘들 정도로 광범위해졌다.