• 한국대기환경학회지
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• 제25권5호
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• pp.402-409
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• 2009

Sodium bicarbonate ($NaHCO_3$) was used as a reactant for the removal of acid gases from a waste incinerator. The removal efficiencies of HCl and $SO_x$ were tested with a reactant mixing apparatus and a distributor installed at the bag filter inlet. It was shown that the stoichiometric ratio of $NaHCO_3$ to the acid gases which allows a removal of over 90% for both HCl and $SO_2$ was about 1.2. When a reactant mixing apparatus was installed on the duct, the removal efficiencies of HCl and $SO_2$ at the end of the duct were increased by approximately 1.5 and 3 times respectively, compared to when the apparatus was not installed. At the end of the bag filter, the removal efficiencies of the both were as high as 98% with a stoichiometric ratio of 1.35. Installing a reactant mixing apparatus on the duct and a distributor at the entrance of the bag filter and using $NaHCO_3$ as a reactant helped overcome the problem of low removal efficiencies of acid gases by dry scrubbing.

• 항공우주기술
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• 제11권2호
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• pp.73-79
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• 2012

저궤도 위성은 지상과 교신할 수 있는 시간이 매우 제한되어 있으므로 위성에서 생성되는 모든 원격측정 데이터는 대용량 메모리에 저장되었다가 지상교신 시 실시간 데이터와 함께 지상으로 전송된다. 대용량 메모리는 최초 시스템 초기화 과정에서 초기화가 시작되어 각 블록의 상태정보가 생성되고 원격측정데이터를 저장할 수 있는 준비를 한다. 운영 중에 계속적으로 대용량 메모리에 원격측정데이터를 저장하고, 저장된 데이터를 지상으로 전송한다. 그리고 우주환경에서 발생할 수 있는 메모리 오류를 제거하기 위하여 주기적으로 메모리 스크러빙을 수행한다. 본 논문은 저궤도위성 원격측정 데이터 처리를 위한 대용량 메모리 운용방식에 대한 것으로 대용량 메모리 구조, 메모리 초기화 및 메모리 스크러빙 방식, 대용량 메모리를 통한 원격측정데이터 저장 및 전송 방식, 주/부 대용량 메모리 운용 방식에 대해서 기술한다.

• 한국응용과학기술학회지
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• 제32권1호
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• pp.48-55
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• 2015

전 세계적으로 증가하고 있는 선박 배출가스 규제를 위해 국제해사기구(IMO)는 배출되고 있는 가스의 부정적 환경영향에 대한 부각과 함께 법적인 규제를 강화하고 있다. 국제해사기구(IMO) 규제에 따라, 발트 해 연안을 지나는 모든 배들은 배출가스 제거창치를 장착해야 한다. 다양한 최신 탈황/탈질 장치가 소개되고 있는 가운데, 선박의 제한 된 공간을 활용한 폐 세정액 회수 공정 또한 중요한 기술로 발전 가능하다. 탈황/탈질 장치 후단에서 발생되는 폐 세정액은 질산암모늄, 황산암모늄과 같은 유용부산물을 포함하고 있다. 본 연구는 선택적 유기용매 염석 법, 저온 결정화 추출, 열 감압농축을 이용하여 유용부산물로서 질산암모늄을 추출하였다. 열 감압농축으로 얻어진 부산물을 반복적 유기용매 추출방법으로 정제했을 시 가장 높은 순도의 질산암모늄이 추출 되었다. 분석 장비를 통해 추출 된 유용 부산물의 성분 및 특성을 평가하였다.

• 한국수자원학회논문집
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• 제32권3호
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• pp.311-319
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• 1999

기존의 정수처리 공정인 응집 ·침전·모래여과를 단일 공정인 막분리 공정으로 대체하기 위한 중공사 정밀여과막의 적용 가능성을 검토하였다. 실험은 우선 실험실 규모의 실험에서 여러 가지 운전인자에 대한 수질의 안정성 및 장기 운전 가능성을 검토하였고, 여기에서 최적 운전인자로 얻어진 투과플럭스 0.03m/h, 10분 여과, 2분 정지 (30초간 air scrubbing 세정 포함)의 조건으로 20m3/일 규모의 Pilot Plant를 1년 이상 운전하여 안정성을 검증하는 방법으로 수행되었다. 탁도, SS등 막 투과수 수질은 전 실험 기간 동안 탁월한 제거효율을 나타내었다. 따라서 정수처리 공정에의 중공사 정밀여과막을 이용한 막분리 공정은 적용 가능하다고 판단된다.

• 대한한의학방제학회지
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• 제18권2호
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• pp.77-91
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• 2010

The purpose of this study is to expand the prescription usage from internal treatment to external treatment by applying the compatibilities of herbal ingredient for ointment massage therapy. For this, specific cases of usage were investigated in Donguibogam, which is now inscribed on the UNESCO Memory of the World Register, has been not only one of the classics of Korean medical asphere, but has compiled all the contents of the Oriental medical traditions including ointment massage therapy that was completed through different Chinese dynasties, such as Song (宋), Jin(金) and Won(元) by the 17th century. Research results of this study is : 1. Ointment Massage Therapy was used to treat the symptoms of diseases such as ACHI-mun(dental range : 牙齒門), PI-mun(dermal range : 皮門), JECHANG-mun (sore range : 諸瘡門), SO A-mun(pediatrics range : 小兒門). 2. Out of all the manipulations, it is a scrubbing manipulation that used most. 3. Out of all the formulations of ointment massage therapy, it is powder types and ointment types that most representative formulation.

• 보존과학연구
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• 통권24호
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• pp.81-98
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• 2003

The biodeterioration on Iksan Mireuksaji pagoda has been studied with fucus on application of K201 as a chemical treatment. Total of 39species, including 10 algae, 16 lichens, 6 mosses and 7 unidentified bacteria and fungi, were collected and identified on the surface of the pagoda. Most of them caused serious discoloration on the surface. The effectiveness and stability of K201 was examined by applying it on some part of the pagoda. A mild spraying of solution diluted to half of original reagent was good enough to eliminate all the deteriorating species on the surface. Most of discoloration disappeared after the treatment except the red color caused by iron substance. The effectiveness of the regent was compared with water wash. The stone was first washed with water and the dirt on the surface was scrubbed off from the surface. The initial surface of the stone was clearer in water wash. However, many of the deteriorating species reappear in 4 weeks after water wash. Although spraying of the reagent K201 could noteliminate all the remnant of dead organisms as good as scrubbing the surface, no deteriorating algae or lichen was observed until two month after treatment. Therefore, spraying method with chemicals seems more stable and reliable way to remove the biodeterioration than physical scrubbing of the surface.

• Journal of Korean Society for Atmospheric Environment
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• 제15권E호
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• pp.29-38
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• 1999

This study identified emission sources and emissions of air pollutants such as volatile organic compounds (VOCs), solvents, and acid gases produced from chemical plants. We collected air samples from various processes, reactors and facilities using VOC detectors and workers' experience. We identified chemical structures and emission concentrations of air pollutants. We analyzed total emissions of air pollutants emitted from the chemical plants. Also, we developed some emission reduction technologies based on chemical types and emission situations of the identified air pollutants. For reduction of air emissions of acid gases, we employed a method improving solubility of pollutants by reducing scrubber operation temperature, increasing surface area for effective contact of gas and liquid, and modifying or changing chemicals used in the acid scrubbers. In order to reduce air emissions of both amines and acid gases, which have had different emission sources each other but treated by one scrubber, we first could separate gas components. And then different control techniques based on components of pollutants were applied to the emission sources. That is, we first applied condensation and then acid scrubbing method using H2SO4 solution for amine treatment. However, we only used an acid scrubbing method using H2O and NaOH solution for acid gas treatment. In order to reduce air emissions of solvents such as dimethylformamide and toluene, we applied condensation and activated carbon adsorption. In order to reduce air emissions of mixture gases containing acid gases and slovents, which could not be separated in the processes, we employed a combination of various air pollution control devices. That is, the mixture gases were passed into the first condenser, the acid scrubber, the second condenser, and the activated carbon adsorption tower in sequence. In addition, for improvement of condensation efficiency of VOCs, we changed the type of the condensers attached in the reactors as a control device modification. Finally, we could successfully reduce air emissions of pollutants produced from various chenmical processes or facilities by use of proper control methods according to the types and specific emission situations of pollutants.

• 한국보건간호학회지
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• 제16권1호
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• pp.123-134
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• 2002

In order to investigate dental caries and oral health status of Kindergarten children, a study was conducted from 1st December, 2000 to 21st January 2001. The subjects were consisted of 117 toddler and pre-school children who were enrolled in 4 kindergartens in a county of Kangwondo. A structured questionnaire was used for dental health behavior and dental examination was given by dentist for detecting dental caries The result were as follows: 1. As for the oral health behavior, 71.8% of subjects brushed their tooth twice a day, 18.8% of them once a day, 8.5% of them 3 times a day and 0.9% of them do not brushed. 68.6% of children brushed their teeth in the morning and evening, 20.7% of them before go to bed, 7.4%, and 2.5% of them after meal and before brak first. 71.7% of children used combined with scrubbing and vertical method, 28.3% of them used scrubbing method. 61.5% of their mother answered they observed oral status of children regularly. 2. Prevalence rate of dental caries (dft) was 68.4%. The prevalence rate of dft were significantly higher in the old age children, mother's lower educational level. nourishing with breast feeding, using bottle, irregular eating of snacks 3. Mean dft was 2.95 ; decayed and filled teeth was 1.97 and 0.98, respectively. The mean dft were significantly higher in the old age children, mother's lower educational level

• 대한인간공학회지
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• 제30권3호
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• pp.427-435
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• 2011

Objective: The objective of this study was to evaluate a work of building cleaners using the ergonomic methods. Background: Previous studies about cleaning worker describe typical physical demands of this work. They found that the most significant risk factors associated with the physical work of cleaners are static loads and repetitive movements and high output of force. Method: A head of ergonomics estimation was work analysis(define of combined task, work tool, work time and frequency of combined task) and posture analysis of worker. Results: The results showed that combined task of building cleaners was classification sweeping, mopping(wet), mopping(oil), moving barrels/carts, dumping trash bags, scrubbing, arrangement of cleaning tool, arrangement of circumferential, moving of cleaning tool, and waiting. The work time of combined task such as mopping(wet) and scrubbing indicated high ratio. The posture analysis of building cleaners indicated high value in bending of the head, lower arm, and hands. Conclusion: The findings appear to indicate that building cleaner were related to high risk of work-related musculoskeletal disorders. So, building cleaner would be required an interventional strategy, improvement of cleaning tools and working environment. Application: If ergonomics rule can be integrated into existing cleaning tools and work environments, the risk of occupational injuries will be reduced.

• 한국광물학회지
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• 제19권1호통권47호
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• pp.1-5
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• 2006

본 연구에서는 $0.1{\sim}0.3mm$ 입도의 규석을 대상으로 물리적 선별공정을 적용하였을 때의 정제효과를 조사하였다. $SiO_2$ 품위가 99.41 wt.%, 99.54 wt.%이고 불순물 함량이 각각 5,864 mg/kg과 4,568 mg/kg인 시료에 대하여 자력선별, 비중선별 및 scrubbing 공정을 단계별로 적용시킨 결과, 주요 불순물인 철 성분은 자력선별에 의하여, 알루미늄 성분은 비중선별에 의해 효과적으로 제거되었다. 최종 정제산물의 $SiO_2$ 품위는 99.98 wt.%였으며, 산출율은 각각 79.05 wt.%와 75.43 wt.%였다. 이때 불순물의 함유량은 각각 126 mg/kg, 174 mg/kg을 나타내어, 불순물의 제거율은 97.85wt.%, 96.19 wt.%였다. 따라서 물리적 분리 선별에 의하여 저급 품위(Low grade)의 규석을 불순물 함유량이 200 mg/kg 이하인 중 고급 품위(Medium-high grade) 이상으로의 품위 향상이 가능하였다.