• 한국해양환경ㆍ에너지학회지
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• 제4권3호
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• pp.28-39
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• 2001

광양만의 수질현황을 파악하고 환경변동에 따른 수질을 예측해서 부영양화를 억제하고 수질 환경회복을 위한 적절한 수질관리대책을 제시하기 위해서 생태ㆍ유체역학 수치모델을 이용하였다 광양만에 대한 점원 오염부하량의 약 90%가 폐수배출부하량이 차지하는 것으로 나타났으며, 부영양화 기준인 Chl. α 10㎍/L이하와 해역수질환경기준 II등급인 COD 2㎎/L이하를 지속적으로 유지하기 위해서는 현재의 점원 오염부하량의 약 35%이상 저감하는 대책이 요구되는 것으로 예측되었다.

• 한국태양에너지학회 논문집
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• 제35권1호
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• pp.53-60
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• 2015

The ECO2 building energy simulation program is used on the assessment project for building energy certification of non-dwelling buildings in Korea. In the design of energy efficient buildings, it is beneficial to identify the most important design parameters in oder to more efficiently develop alternative design solutions or reach optimized design solutions. The sensitivity analyses will be used at a reasonable early stage of the building design process, where it is still possible to influence the most important design parameters. In this study, the sensitivity analysis is focused on building envelope parameters such as U-values, SHGC and Wall-window ration.

• 한국입자에어로졸학회지
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• 제9권2호
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• pp.103-110
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• 2013

The electrostatic precipitator (ESP) has been used for degrading atmospheric pollutants. These devices induce the electrical forces to facilitate the removal of particulate pollutants. The ions travel from the high voltage electrode to the grounded electrode by Coulomb force induced by the electric field when a high voltage is applied between two electrodes. The ions collide with gas molecules and exchange momentum with each other thus inducing fluid motion, electrohydrodynamic (EHD) flow. In this study, for the simulation of electric field and EHD flow in ESPs, an open source EHD solver, "espFoam", has been developed using open source CFD toolbox, OpenFOAM(R) (Open Field Operation and Manipulation). The electric potential distribution and ionic space charge density distribution were obtained with the developed solver, and validated with experimental results in the literature. The comparison results showed good agreement. Turbulence model is also incorporated to simulate turbulent flow; hence the developed solver can analyze laminar and turbulent flow. In distributions of electric potential and space charge, the distributions become distorted and asymmetric as the flow velocity increases. The effect of electrical drift flow was investigated for different flow velocities and the secondary flow in a flow of low velocity is successfully predicted.

• 한국농촌건축학회논문집
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• 제20권4호
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• pp.1-8
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• 2018

In this study, we survey the 2 buildings at the Central 1 and 8 buildings at the Central 2, which are divided by each climate region in the rural regions. Major heat loss factors are 47% loss of the outer shell including outer wall, roof, and bottom, 30% loss through window, and 23% loss through crevice wind. We analyze the energy simulation of ECO2 program to construct a zero energy building regarding village hall located in Jung Juk 4-le at Centeral 2. We simulate the primary energy requirement regarding village hall and the simulated results show the $265.3kWh/m^2{\cdot}a$ and it may estimate '2' energy efficiency grade. The energy requirement regarding village hall is the $183.2kWh/m^2{\cdot}a$ when the passive technology are applied in village hall. We research total amount of energy requirement in village hall when the passive and active technologies such as solar cell with 3kW and solar thermal with $20m^2$, geothermal power with 17.5kW. The simulated results show the improved energy efficiency certification grade with $1^{{+}{+}{+}}$ due to the reduced primary energy requirement with 73% when passive technology including 3kW of solar panel is applied and the energy independence rate is 54%, which is estimated to be 4th grade of zero energy buildings. The order of energy consumption are solar panel, solar thermal, and geothermal power under applied passive technology in the building. In order to expand the zero energy building, it is necessary to introduce the zero energy evaluation system in the rural region.

• 한국환경과학회지
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• 제15권10호
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• pp.951-960
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• 2006

The eco-hydrodynamic model was used to estimate the environmental capacity in Gamak Bay. It is composed of the three-dimensional hydrodynamic model for the simulation of water flow and ecosystem model for the simulation of phytoplankton. As the results of three-dimensional hydrodynamic simulation, the computed tidal currents are toward the inner part of bay through Yeosu Harbor and the southern mouth of the bay during the flood tide, and being in the opposite direction during the ebb tide. The computed residual currents were dominated southward flow at Yeosu Harbor and sea flow at mouth of bay, The comparison between the simulated and observed tidal ellipses at three station showed fairly good agreement. The distributions of COD in the Gamak bay were simulated and reproduced by an ecosystem model. The simulated results of COD were fairly good coincided with the observed values within relative error of 1.93%, correlation coefficient(r) of 0.88. In order to estimate the environmental capacity in Gamak bay, the simulations were performed by controlling quantitatively the pollution loads with an ecosystem model. In case the pollution loads including streams become 10 times as high as the present loads, the results showed the concentration of COD to be $1.33{\sim}4.74mg/{\ell}(mean\;2.28mg/{\ell})$, which is the third class criterion of Korean standards for marine water quality In case the pollution loads including streams become 30 times as high as the present loads, the results showed the concentration of COD to be $1.38{\sim}7.87mg/{\ell}(mean\;2.97mg/{\ell})$, which is the third class criterion of Korean standards for marine water quality. In case the pollution loads including streams become 50 times as high as the present loads, the results showed the concentration of COD to be $1.44{\sim}9.80mg/{\ell}(mean\;3.56mg/{\ell})$, which is the third class criterion of Korean standards for marine water quality.

• 대한건축학회논문집:구조계
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• 제34권11호
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• pp.55-62
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• 2018

To receive financial support for the Green Remodeling, applicants must submit an energy simulation report. However, many of the applicants are not green remodeling specialist and energy simulation services are too expensive for them. For this reason, this study was to develop an energy simulation program to enhance green remodeling for the non-specialist such as housewives. Firstly, to enhance understanding and accessibility improvement energy simulation, simulation process was designed four steps and reducing input data. Specifically, input data was reduced by categorizing the following for the area, plan type, hot water load, electricity load, statistical inference. And then, to accurately verify the calculation result, the heat and hot water demand were derived and compared with ECO2 and Energy # program. Lastly, the calculation shows that there is a difference of 4% for the heat load and 15% to 33% for the hot water load respectively.

• 해양환경안전학회지
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• 제15권2호
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• pp.91-98
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• 2009

아산만 해역으로 방류수가 배출될 경우, 생태-유체역학모델을 이용하여 아산만 해역의 장기 수질변화를 예측하였다. 생태-유체역학 모델은 해수유동 시뮬레이션을 위한 다층모델과 수질시뮬레이션을 위한 생태계모델로 구성되어 있다. 생태-유체역학모델을 이용하여 아산만해역의 장기 수질을 예측한 결과, 5개 정점에서 화학적산소요구량, 용존무기질소 및 용존무기인의 농도분포는 현재 계산결과에서 6개월 동안 증가하였다. 수치실험 수행시간 1년에서 2년 사이에서는 화학적 산소요구랑, 용존무기질소, 용존무기인의 농도분포는 6개월 동안 증가한 농도분포가 차츰 감소하는 경향을 보였으며, 3년에서 10년 사이에서는 일정한 농도분포를 보였다. 화학적 산소요구량, 용존무기질소 및 용존무기인의 농도는 $11{\sim}67%$, $10{\sim}67%$ 및 0.57%의 범위로 증가하였다. 10년 동안의 수치 실험 결과 화학적산소요구량과 용존무기질소의 변화 폭이 크게 나타났으며 이는 하수처리장의 방류수 중 이 두 오염부하량이 많은 양을 차지하고 있기 때문이다. 아산만 연안해역에서 화학적산소요구량, 총질소, 총인의 농도는 해역수질환경기준 II등급으로 조사되었으나, 하수처리장의 방류수가 배출될 경우 사업지구 인근의 아산만 방조제 부근에서는 해역수질환경기준 III등급으로 나타났다.

• 토지주택연구
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• 제2권3호
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• pp.299-305
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• 2011

하천과 강은 지구상에서 가장 현란하고 복잡한 생태계를 가지고 있는 지구상의 생태 중 하나이다. 최근, 전국적으로 생태하천에 대한 관심이 높아져가고 있는 현실에서 각 지역마다 생태하천 구성을 위한 계획들이 수립되어 시행되고 있다. 생태하천 조성을 위해서는 수질과 연계한 생태하천의 유지용수 확보가 가장 큰 문제임에도 불구하고 너무 많은 변수들로 최적의 의사결정을 도출하기가 쉽지 않다. 본 연구에서는 의사결정자가 주민인식조사와 연계하여 생태하천조성을 위한 의사결정을 지원할 수 있도록 시스템을 개발하였다. 의사결정지원시스템은 수리 수질 생태하천 모의모형과 최적의 생태하천유량 산정방안과 수질개선방안을 제시할 수 있도록 구성하였다.

• 조명전기설비학회논문지
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• 제25권1호
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• pp.9-17
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• 2011

Development of high efficiency and eco-friendly LED source has been progressed continuously. Also, by nation's regulations, public institutions have changed existing luminaires to LED luminaires. However, there are several differences between existing luminaires and the intensity distribution of general planar LED luminaires. In case of changing existing luminaires to LED luminaires, by such differences, there are inefficiencies both quality aspect and energy aspect in luminous environment. Therefore, this study aims to conduct a study on the changes of intensity distribution and luminous environment by reflector shapes in indirect reflected LED luminaires with software for optical design of a luminaire (Photopia 2.0) and lighting design of a space (ReluxPro). This study shows the changes of intensity distribution and luminous environment of indirect reflected LED luminaires and indirect fluorescent lamp luminaires by reflector shapes.

• 한국자동차공학회논문집
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• 제19권6호
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• pp.68-75
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• 2011

A vehicle fuel economy is very important issue in view of fuel cost and environmental regulation. It has been improved according to the performance improvement of the vehicle engine, power train and many components. It was evaluated at given mode (LA-4, FTP-75, etc) on an engine dynamometer or computer simulation program. In this paper, the fuel economy improvement cruise control algorithms as controling a vehicle velocity by road load calculated and predicted in a real expressway with gradient was studied. Firstly, the altitude and distance data which was measured with GPS sensor was already installed in the ECU of a vehicle. Then the vehicle equipped with GPS receiver is driven the same expressway. The ECU calculates the gradient angle and the in-/decreasing velocity using the gradient angle by comparing the current received distance and altitude data from GPS with the saved data ahead of the vehicle. Therefore the ECU can calculate and predict the vehicle velocity considering tolerance velocity of next position with running. Then the ECU controls the vehicle velocity to meet this predicted velocity in all section. Three cruise control algorithms with the different velocity profiles for the improvement of fuel economy are proposed and compared with the computer simulation results that the vehicle runs on Youngdong expressway. The proposed CVELCONT2 and CVELCONT3 algorithms were improved 3.7% and 4.8% of fuel economy compared with CONSTVEL which is steady cruising algorithm. These two algorithms are recommended as the Eco-cruise drive methodologies in this paper.