• Journal of Korea Far Infrared Association
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• s.24
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• pp.32-37
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• 2005

공기이온에 관한 연구는 많은 분야의 연구원 참여에 의해 폭넓게 알려져, 반세기에 이르는 번영의 역사를 쌓아 왔지만, 불가사의하게도 현재, 가장 중요한 적용분야인 보건 분야에서 위기를 맞고 있다. 20세기 초, 대기 중에 전하를 띤 입자의 존재가 관찰된 이래, 공기 이온의 성질을 문제로 한 기초적 연구가, 간단한 공기이온계측기 보급과 함께, 물리학자, 생물학자, 의학자의 협력 하에 1930년대 이후 활발히 이루어져, 공기이온의 위생적ㆍ치료적 가치에 대한 풍부한 정보를 얻을 수 있게 되었다. 어찌되었든 이온화환 공기 속에서는 생활할 수 없는 것이 확실해져, 어떤 농도의 공기이온은 사람 및 동물의 생체에 유익한 작용을 하고, 대용량 공기이온은 치료에 적용가능하지만, 농도의 여하에 관계없이, 양이온이 음이온에 비해 2~3배 우세하면, 신체의 상태를 악화시켜며, 또한 공조설비와 필터류는 모두 이온화작용을 나타내는 것도 밝혀졌다. 청정한 공기를 이온화하는 것은 산소, 탄산가스, 약용물질분자를 활성화시키지만, 오염된 공기의 이온화는 유독한 불순물의 독성을 증가시키는 점도 지적되었다.

• Journal of the Institute of Convergence Signal Processing
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• v.19 no.4
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• pp.167-173
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• 2018

We propose an air purification system that utilizes aerial plant parts and root zone of indoor plants where light is insufficient and air circulation is bad. In order to maximize the air purification effect of the plant, the aerial plant parts illuminates mixed light combining blue and green LED and CRI(Color Rendering Index) LEDs close to natural light, respectively. And the root zone was forcibly circulated by the fan to use the soil as a filter. The indoor air purification system combined with the light source and the fan removed most polluted air in the shortest. In the case of mixed light and CRI LEDs of indoor air purification system, fine dust decreased by 14%, 14.2%, and TVOC(Total volatile organic compounds) decreased by 7.5% and 9.4%, respectively. In the experiment in which the fan was operated for 15 minutes, the TVOC decreased to 97.8%. The photosynthesis of the plant and the use of soil as a filter were able to purify polluted air in a short time. And the fan's temporary operation gave the similar effect of continuous operation.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.16 no.1
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• pp.868-876
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• 2015

This study was conducted to measure the concentrations of total culturable bacteria (TCB) and to identify the bacteria in thirty public facilities (7 elderly-care facilities, 4 hypermarkets, 4 university hospitals, 7 child care facilities, 4 subway stations and 4 bus terminals) in Seoul and Gyeonggi-Do Province. Although all concentrations measured in these study facilities did not exceed the national maintenance standard, it is believed that elderly-, child-care facilities should be high priority facilities to improve the indoor air quality and it is important to study the health effects and the airborne bacteria concentration of public facilities including non-culturable bacteria or allergen.

• Journal of the Korean Geosynthetics Society
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• v.6 no.3
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• pp.9-16
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• 2007

Soil vapor extraction (SVE) is an effective and cost efficient method of removing volatile organic compounds (VOCs) and petroleum hydrocarbons from unsaturated soils. Incorporating PVDs in an SVE system can extend the effectiveness of SVE to lower permeability soils by shortening the air flow-paths and ultimately expediting contaminant removal. With this approach, the real bounded system is replaced for the purposes of analysis by an imaginary system of infinite areal extent. The boundary conditions for the contaminant remediation model test include constant head and no flow condition. Due to these parallel boundaries conditions, image wells should be developed in order to maintain the condition of no flow across the impermeable boundary. It is also assumed that the flow is drawdown along the constant head boundary condition. The factors contributing to the difference between the theoretical and measured pressure heads were also analyzed. The flow factor increases as the flow rate is increased. The flow rate is the most important factor that affects the difference between the measured and theoretical pressure heads.

• Journal of Soil and Groundwater Environment
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• v.13 no.6
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• pp.23-30
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• 2008

Air sparging technique has been used for remediation of VOC(volatile organic compound)-contaminated aquifer. The aim of this study was to develop an innovative air sparging technique that enhances the efficiency of air intrusion into a specific horizontal layer of aquifer where the contaminants exist with the help of water-soluble surfactant. A twodimensional physical box model, packed with homogeneous sand, was used for simulating the aquifer in this study. Aqueous solution of anionic surfactant (100 mg/L, sodium dodecylbenzene sulfonate) was used to suppress the surface tension of groundwater. Three sets of experiments were conducted: air sparging experiment without surfactant application, air sparging experiments for box model where the surfactant solution was applied right above the air injection point, and air sparging experiments with surfactant solution layer formed in the middle of the box. It was found that the sparging influence zone was expanded up to five times of that formed by sparging without surfactant application. The size of sparging influence zone was more sensitive to the air flow (injection) rate with surfactant application than that without surfactant. More importantly, injection of air into the target aquifer layer was successful with surfactant application. Findings in this study are expected to provide more options for designing remediation processes using air sparging.

• Journal of Environmental Policy
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• v.7 no.2
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• pp.67-90
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• 2008

The purpose of this study is to develop indoor air quality management strategies regarding indoor air pollutants while considering various factors affecting indoor pollutants concentration. The Integrated Indoor Air Quality model(IIAQ) developed by Seoul National University is used for this study. The IIAQ model is a tool that can provide an integrated view to indoor environmental pollution by simulating suggested scenarios. The results of the modeling are used to assess health risk. The concentrations that are used for the risk characterization are weighted concentrations based on the period of time in each place and existing Indoor Air Quality(IAQ) standards. The estimated concentration of toluene and formaldehyde for 10 years through the IIAQ model was 207.3 $ug/m^3$ and 36.4 $ug/m^3$ in indoors, and 55.9 $ug/m^3$ and 8.62 $ug/m^3$ in outdoors. These concentrations are lower than the existing IAQ standards. The estimated carcinogenic risk of formaldehyde is up to 1.05E-03 for the adult male group and exceeds 1E-06 for all receptor groups. This value means that cancer could affect one person out of 1000. The estimated non-carcinogenic risk of toluene was lower than 1, which means that there was no serious non- carcinogenic risk. The result of modeling shows that using low emitting indoor sources is the most effective strategy for both formaldehyde and toluene. This risk assessment suggests that the total exposure levels of existing IAQ standards may cause serious carcinogenic risk. In order to avoid uncontrolled risk, it is suggested that the current IAQ standards should be adjusted by taking into account the total amount of exposure from all exposure pathways from indoor and outdoor sources.

• Proceedings of the Korea Water Resources Association Conference
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• 2022.05a
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• pp.474-474
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• 2022

미세플라스틱이 물 환경으로 배출되는 주요 경로로는 하수처리장 방류수와 강우유출수가 있다. 하수처리장 및 유역에서 배출된 미세플라스틱은 하천과 하구역을 거쳐 해양과 같은 대규모 수역으로 이동하는데, 이 과정에서 해양뿐만 아니라 담수호, 저수지 등과 같은 공공수역에도 미세플라스틱이 지속적으로 축적되고 있다. 특히 강우유출수에 포함된 미세플라스틱은 적절한 처리 과정 없이 하천으로 유입되는 경우가 많아 공공수역 내 미세플라스틱 저감 기술의 필요성이 증가하고 있다. 그러나 미세플라스틱 관련 기존 연구는 미세플라스틱의 분포 등 현황에 대한 모니터링 및 환경위해성과 관련한 것이 대부분이며, 미세플라스틱 저감기술 관련 연구 또한 일부 정수처리 및 하수처리 공정을 대상으로 하는 초기 단계의 연구가 진행되고 있을 뿐 공공수역에서의 미세플라스틱 저감기술 개발 관련 연구는 전무한 실정이다. 따라서, 본 연구에서는 기존의 물리·화학적 수처리 공정인 용존공기부상법(Dissolved Air Flotation, DAF)에 물의 전기분해 시발생하는 브라운가스를 활용하여 응집된 물질을 빠르게 부상시켜 수체 내 오염물질을 제거할 수 있는 기술을 통해 수체 내 미세플라스틱 저감효과를 분석하였다. 또한, 해당 기술을 공공수역인 저수지에 적용하여 오염물질과 함께 미세플라스틱을 제거할 수 있는지 검토하였다.

• Korean Journal of Environmental Agriculture
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• v.19 no.4
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• pp.284-293
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• 2000

For the artificial removal of air pollutants such as pesticides, environmental toxicants, and pathogenic microorganisms in the greenhouse or the living environment, the accelerated photodegradation and the biocidal effects of some photosensitizers (PS)/photocatalysts (PC) were tested under the sunlight and/or artificial light. The selected photosensitizers/photocatalysts included the semiconductors (PC-1 and PC-2), the oxidizers (PC-3, PC-4, PC-5 and PC-6), the aromatic ketone (PS-7) and the aromatic amine (PS-8). In the case of dichlorvos, all the photocatalysts selected showed more accelerated photodegradation than the control without photocatalysts under both the sunlight and artificial light. Whereas, only the photocatalyst PC-1 accelerated the degradation of methyl tert-butyl ether about 17 times more than the control under both the sunlight and artificial light. Procymidone was much more degraded by the photosensitizer PS-8 and the two photocatalysts (PC-1, PC-6) than by PS-7. In the preliminary experiments to diminish the population of the microorganisms in the air, the photocatalyst PC-1 added to the suspensions of Pseudomonas putida, Phytophthora capsici, and Salmonella typhimurium obviously inhibited the microbial growth under the artificial light. The photocatalyst PC-1 showed a bactericidal activity against Salmonella typhimurium spread on the nutrient broth agar medium. These results suggest that the photosensitizers/photocatalysis under the light can remove some air pollutants and hence they can be used to reduce the exposure of the workers in the horticultural facilities and/or the public in the environment to the harmful pollutants.

• Proceedings of the Korea Air Pollution Research Association Conference
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• 2003.05b
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• pp.97-98
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• 2003

나노/서브마이크론 크기의 입자는 최근 유해 입자상 물질 제거 및 오염 제어나 물질 제조 등의 분야에서 관심이 높아지고 있다. 보통 환경 입자상 물질로 불리는 0.1~l $\mu\textrm{m}$ 범위의 서브마이크론 입자는 자동차, 공장, 발전소, 소각로 등의 연소 과정에서 발생되어 상당량이 대기로 배출되는데, 인체에 유입되면 호흡기 장애나 암을 유발하는 등의 나쁜 영향을 미친다. 특히, 관성력과 확산력에 의한 영향이 적고 하전 입자의 전기적인 이동도도 낮기 때문에 집진장치나 공기청정장치에서 집진효율이 가장 낮은 크기 범위이다. (중략)

• Proceedings of the Korea Air Pollution Research Association Conference
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• 2003.11a
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• pp.75-76
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• 2003

본 연구는 ELPI(Electrical Low Pressure Impactor)를 이용하여 소형디젤기관에서 배출되는 입자상물질의 입경분포를 측정하였으며, 희석공기온도, 희석비, 측정위치가 측정에 미치는 영향을 고찰하였다. 본 연구에서는 배기량이 3000 cc인 간접분사식 소형디젤기관에서 발생하는 입자상물질의 입경분포를 고찰하고자 Dekati사의 ELPI를 사용하였다. 다단임팩터의 오염을 막기위해 ejector 형식의 2단 희석장치를 사용하였다.(중략)