• 전력전자학회:학술대회논문집
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• 전력전자학회 2009년도 정기총회 및 추계학술대회 논문집
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• pp.231-233
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• 2009

The plating equipment, water treatment system, electrolysis facility, etc need the high current and high power rectifier for their original purposes. So the paper investigates the applicable types of rectifiers and carries out their comparisons, and also suggest the practical design guidelines for a suitable candidate rectifier for low voltage high current high power applications.

• 한국콘크리트학회:학술대회논문집
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• 한국콘크리트학회 2006년도 춘계 학술발표회 논문집(II)
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• pp.261-264
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• 2006

Recently, the environment problems are risen to social problems. People have requested the convenience of a human activity and the enhancement of a human quality. The facility was, however, emphasized on the acquisition and treatment of water with the construction and maintenance of a irrigation and drainage structure. The concept of an environmental friendship has been introduced to change our society structure to an environment friendship at 21th century. But the concept lacks theoretical and systematic foundation. So, The maintenance technique, concrete products and construction methods will be made to be an environment friendship. The standards for environment friendship will be presented.

• 전력전자학회:학술대회논문집
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• 전력전자학회 2010년도 하계학술대회 논문집
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• pp.570-571
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• 2010

To reduce the problem of ecocide, the plating equipment, water treatment system, electrolysis facility in ship need high current high power rectifier. This paper shows entire constitution of the proposed high-current rectifier for electrolysis of seawater, describes a way to design controller and analyzes output characteristic of the rectifier.

• 환경위생공학
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• 제10권2호
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• pp.13-22
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• 1995

Most of small- scale livestock facility have difficulties to treat organic wastewater by activated sludge process as distinguished feces and urine. The organic wastewater discharged have characteristics of slurry, high concentration of BOD, 55 etc. This study was performed to estimate suitable condition for the application of packing materials, air flow, pollutant load and so on as important parameter to treat organic wastewater by thermopile oxlc process. As a result obtained at this experiments the most suitable condition for BOD load, air flow indicate 3.0kg · m$^{-3}$ day$^{-1}$,50 ∼ 100L· min$^{-1}$ m$^{-3}$, respectively, and we knew that it was necessary to add waste contained high calories to degrade about 80% of pollutant among waste- water. It showed that plastic material can be used as packing media because it can be provided as inhabitation for microorganism owing to intensity of material and characteristic of keeping moisture.

• 한국원자력학회:학술대회논문집
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• 한국원자력학회 1997년도 춘계학술발표회논문집(2)
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• pp.427-432
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• 1997

Boron neutron capture therapy(BNCT) is a binary treatment modality that can selectively irradiate tumor tissue. More is known now about the radiation biology of BNCT, which has reemerged as a potentially useful method for preferential irradiation of tumors. We design a square reactor (that can easily be reconfigured into polygonal reactors as the need arises) with four slab type assemblies to produce high quality epithermal neutron beans and thermal neutron beams jot use in neutron capture therapy. With a low operating power of 300kW, the heat generated in the core can be removed by natural convection through a pool of tight water. The proposed design in this study could be constructed for a dedicated clinical BNCT facility that would operate very safely.

• 환경영향평가
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• 제8권2호
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• pp.9-20
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• 1999

Until 1993, Nanji landfill has been the main solid waste treatment facility for Seoul, which is the capital of Korea. Since the landfill has not been properly lined, soil and ground water around the landfill has been contaminated. Due to the proximity, it has been speculated that the water quality of the Han River would have been also influenced by the leachate. In order to illuminate this, HELP model to estimate the quantity of the leachate from Nanji landfill and RMA model to simulate the change of water quality in Han River were applied in this research. The result indicates that the quantity of leachate from Nanji landfill has been overestimated by previous works and it was due to the failure to consider the water storage capacity of the landfill. The effect from Nanji landfill leachate on the water quality, in terms of COD input, proves to be smaller than those from other tributaries and influents to the River and the effect is larger when the flow of the River is reversed due to the tide.

• 한국수자원학회논문집
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• 제45권1호
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• pp.101-111
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• 2012

본 논문에서는 시스템 다이내믹스(System Dynamics, SD) 방법론에 입각하여 하수도 시스템의 운영지표들과 이에 영향을 미치는 외부변수들로 구성된 피드백 루프 메커니즘(Feedback Loop Mechanism)을 관로유지관리와 연관하여 규명하고, 외부변수의 변화에 따른 운영지표의 변화를 예측함으로써 하수도 시스템의 효율적인 운영 및 유지관리 방안을 모색할 수 있는 SD 컴퓨터 모의 모형(Computer Simulation Model)을 개발하였다. 개발된 모형에 부산광역시 하수도 시스템의 과거 운영 자료를 적용함으로써 모형을 검증하였고, 미래의 운영 상황을 예측하였다. 그 결과, 하수도보급률은 이미 목표치에 거의 도달하여 큰 변동이 없을 것으로 예측되었으며, 하수처리효율과 하수처리량, 요금현실화율은 점차 증가할 것으로 예측되었다. 또한 정책 지렛대의 발견을 위해 시스템에 큰 영향을 미치는 주요 운영지표를 선정하여 외부변수의 변화에 대한 민감도 분석을 수행하였는데, 그 결과 관로 유지관리와 연관된 외부변수는 하수처리효율의 변화뿐만 아니라 시설이용률, 하수처리량 등의 변화에도 큰 영향을 미치는 것으로 분석되었다.

• 대한영양사협회학술지
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• 제11권4호
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• pp.405-417
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• 2005

The purpose of this study was to evaluate students' satisfaction with foodservice of middle school by region in Gangwon province. Students’ satisfaction concerning foodservice quality characteristics was surveyed by using importance performance analysis(IPA) technique in middle school foodsevice operations. Middle school students from four cities(Gangnung, Sokcho, Wonju, Chuncheon) were surveyed by self-developed questionnaire. Total of 1,025 questionnaires(female 521 and male 504 respectively) were analyzed using SAS program. The results of this study are summarized as follows: 1.The performance level of foodservice quality attributes was significantly different according to region. 2.The attribute of the highest performance level was taste of food. The attributes of the lower performance level were waiting time of meal service and treatment about complaints. The attributes of the higher importance level were hygiene of food and dining room and hygiene of spoon and cup and drinking water table. 3.Satisfied quality attributes identified were taste of food and variety of menu. Dissatisfied quality attribute identified was treatment about complaints. 4.The satisfaction of middle school lunch service was lower than their elementary school period. 5.The satisfied quality attributes of middle school foodservice were portion size, facility of dining room, hygiene of food, variety of menu compared with their elementary school period.

• 상하수도학회지
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• 제18권5호
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• pp.619-627
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• 2004

Purposes of this study were to examine closely the extracellular polymeric substances (EPS) which was a membrane fouling contaminant, to control detected EPS by powdered activated carbon (PAC) dosage etc. and to evaluate the possibility of practical reuse facility. With high removal efficiency of general pollutants, when the PAC is added to MBR, improvement of removal efficiency of $COD_{cr}$, and color was expected and treated wastewater can be reused. It was judged that the correlation between EPS and membrane fouling was very high. Carbohydrate and DNA in the EPS were judged to be cause of membrane fouling. If EPS could be controled, not only membrane fouling would be decreased but also operation time would be extended. In experiment of powdered activated carbon (PAC), characteristics of the best PAC for membrane fouling control were the particle size of $7{\mu}m$, lodine Number of 1,050, surface area of peat of $1,150m^2/g$. In lab test, operation time of MBR by PAC dosage of 200mg/gVSS was longer than one of MBR by without PAC dosage. Because EPS, especially carbohydrate and DNA, was controled successfully by PAC, membrane fouling in MBR could be decreased.

• 한국수자원학회:학술대회논문집
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• 한국수자원학회 2010년도 학술발표회
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• pp.1044-1048
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• 2010

해수를 이용한 세계최초의 해수수로인 송도 신도시 중앙공원 해수수로는 서해안에서 집수된 해수를 $5{\mu}m$의 공극 크기를 가지는 해수처리시설 (STF, seawater treatment facility)에 의해 여과된 뒤 2곳의 해수공급 지점에서 해수수로로 공급된다. 여과된 해수는 수로로 155L/sec의 유량으로 1.8km를 흐른 뒤 서해로 방류된다. 이러한 인공 해수수로에서는 흐름정체에 따른 수질 문제와 영양염에 의한 적조를 유발하는 조류 성장이 문제가 된다. 따라서 본 연구에서는 3차원 수치모형을 이용한 인공 해수수로내의 흐름특성 모의와 수질 모니터링의 통한 조류 생성 특성 및 장소를 비교하여 그 상관성을 분석하고자 한다. 수치모의 실험은 3차원 수치모형인 FLOW-3D를 이용하였으며, 격자망 형태는 직사각형 직각 격자가 사용되었다. 현장 모니터링을 통하여 획득한 수질 데이터와 비교 분석을 통하여 해수수로 내 해수 흐름 특성변화(유속, 와도 등)와 조류생성에 미치는 영향을 비교 분석하였다. 해수 수로내의 평균 유속은 0.01m/s 이었으며, 수로의 형상에 따라서 정체수역이 발생하였다. 이러한 정체수역은 현장 모니터링을 통하여 예측된 조류 발생 지역과 일치하였다. 이러한 흐름 특성과 조류생성과의 상관성 규명을 통하여 인공수로의 물순환 시스템 설계시 조류 생성을 억제할 수 있는 최적 관리를 위한 설계의 기초 자료를 제공할 수 있을 것으로 판단된다.