• 한국대기환경학회지
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• 제19권1호
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• pp.77-84
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• 2003

HS, Ammonia, CH$_4$, VOCs, Microorganism, Bacteria etc produced from swineries or henhouses are known to prevent the growth of livestock. Moreover, they give an unpleasant feeling to the workers. In this study, a methodology to remove odors and toxic gases by oxidation of ozone was thus accomplished. However, most ozone generators which use the atmospheric surrounding air have problems of contamination of electrode for discharge. Therefore in this work, a wire-cylinder type plasma reactor with DC voltage has been used both in a laboratory scale test and in the real swinery to solve the existing problems. About 6 cm of electrode gap could decrease the attachment of dusts, humid aerosols and other polymers, which are contained in the air. This compact designed device could produce ozone to oxidize and remove the air pollutants. But the amount of ozone was not large enough to be harmful to human Health. Also, the concentration of ozone was able to be varied by the input voltage. which makes it available for the proposed system to be installed in various kinds of pig houses. With this device, at maximum 43 mg/㎥ (20 ppm) of ozone could be produced at 40 ㎸ input voltage (consumed energy was 0.1 Wh/㎥). A program was also made in this work to calculate the optimum parameters for design of a plasma reactor in wide range of conditions.

• 동력기계공학회지
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• 제18권4호
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• pp.52-59
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• 2014

The purpose of this study is to evaluate the performance of after-treatment equipment and thermal storage devices for a heat recovery and combustor-type $CO_2$ generator fuelled a kerosene. To reduce the levels of harmful exhaust gases produced by a $CO_2$ generator, a catalyzed particulate filter(CPF) has been selected as an after-treatment device, by considering back pressure and exhaust gas temperature. The CO conversions of the catalyzed SiC filter(full plugging) were 92%, and the concentration of PM(particulate matter) was near ambient. A thermal recovery device was used to recover 13% of the heat energy from the exhaust gas through heat exchangers installed on the exhaust line of the $CO_2$ generator. 69% of the moisture within the exhaust gases was removed by condensing water, in order to minimize excessive humidity within the greenhouse.

• Advances in environmental research
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• 제12권2호
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• pp.95-111
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• 2023

Pollution, climate change, and waste accumulation are only some of the new problems that have arisen because of the exponential population growth of the past few decades. As the global population expands, managing municipal solid trash becomes increasingly difficult. This is by far the most difficult obstacle for governments to overcome, especially in less developed nations. The improper open dumping of trash, which is causing mayhem across the country, has two immediate effects: it contaminates groundwater and surface water. Air pollution and the accumulation of greenhouse gases are both exacerbated by the release of methane and other harmful waste gases. Leachate from the landfill leaks underground and pollutes groundwater. In most cases, leachate moves into the groundwater zone and pollutes it after forming in association with precipitation that infiltrates via waste. This has far-reaching effects on people's health and disturbs the natural environment. This review article critically examines the current state of Solid Waste Management (SWM), addressing both the highlighted concerns and the government management solutions that have been put in place to address these issues. In addition, the constraints, and difficulties that India will face in the future in terms of solid waste management and the role of models for such a system are discussed.

• 한국산학기술학회논문지
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• 제12권1호
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• pp.375-383
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• 2011

디지털 기술의 눈부신 발전과 인터넷 서비스의 다양화로 인하여 USN 시스템에서 임베디드 웹서버를 이용한 모니터링 시스템에 관한 연구가 활성화 되고 있는 추세이다. USN 시스템 구성 시 무선센서 모듈들을 사용할 경우 센서를 정상적으로 동작시키기 위해 히팅 전력이 필요한 센서에서는 과도한 전력 소모에 의해 효율적이지 못하다. 본 연구에서는 웹 환경에서 임베디드 시스템을 이용한 VOC 센서 신호 원격 모니터링 시스템개발을 목적으로 USN 시스템에서 센서 모듈들로부터 직렬버스 방식으로 오염 데이터 스트림을 처리하는 방법을 제안하였다. 센서 모듈의 전력을 직렬버스 라인과 함께 전력을 공급하도록 반연구적으로 실시간 적인 오염 감시를 할 수 있는 장점을 보유하고 있다. 오염 검출 대상은 페인트와 같은 화학물질에서 다량 검출되는 Toluene가스를 대상으로 하였으며 센서 모듈은 FIGARO사의 TGS-2602 VOC(Volatile Organic Compounds)센서로 구성하고 검출된 신호는 직렬버스 방식인 RS-485를 이용하여 임베디드 웹서버로 전송하였다. 검출된 신호는 사용자가 웹상에서 실시간으로 모니터링 할 수 있도록 하기위하여 VOC 센서 모듈과 임베디드 웹서버(EMPOS-II)를 연동하여 인터넷이 연결되어 있는 어느 곳에서나 유해 물질 검출 여부를 모니터링하고 감시할 수 있는 원격 VOC 센서 신호 모니터링 시스템을 구성하였다.

• Korean Chemical Engineering Research
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• 제60권4호
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• pp.519-524
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• 2022

국내 건축물 마감재는 국토교통부 고시에 따라 KS F 2271 기준에 의해 평가되어지고 있으며, 이 실험은 실험동물을 사용하여 평가하고 있다. 본 연구에서는 가연성이 높은 유기물 단열재 EPS, 우레탄, 페놀폼에 대해 실험을 진행하였다. 이 3종의 단열재가 연소 시 발생되는 유해성 가스에 의한 실험용 쥐의 평균행동정지시간을 측정하여, 실험용 쥐의 행동정지에 대한 원인을 분석하고자 하였다. 실험용 쥐의 행동정지에 대한 원인분석방법으로는 FTIR 분석과 연기밀도실험을 진행하였고, 마우스의 행동정지 원인을 입자상물질에 의한 질식과 가스상물질에 의한 독성흡입으로 구분하여 실험결과를 분석하였다. 실험결과 우레탄이 가장 유해한 단열재로 평가되었으며, 가스유해성 실험결과에 대한 원인분석으로 FTIR분석과 연기밀도 실험을 진행한 결과, 독성흡입에 의한 영향보다 질식에 의한 실험용 쥐의 행동정지가 높은 것으로 나타났다. 본 연구는 유해성가스의 원인분석에 대한 기초연구로서, 독성의 근거를 마련하고 나아가 다양한 재료와 가스에 대한 분석을 통하여 보다 구체적인 독성평가의 기준이 마련될 수 있을 것으로 기대된다.

• 한국산학기술학회논문지
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• 제18권9호
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• pp.473-479
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• 2017

환경오염과 인체의 유해성 및 지구온난화로 인하여 자동차의 파워트레인의 변화가 심화되고 있으며 전기자동차의 시장점유율이 상승하고 있다. 또한, 화석연료를 기반으로 하는 내연기관 자동차의 엄격한 배기가스규제를 충족시키기 위해 자동차와 선박용 후처리장치의 비중이 점차로 증가하고 있다. 이 연구의 목적은 CNG 버스에서 배출되는 유독성 가스를 저감하는 NGOC의 $CH_4$와 NOx 저감 능력 향상을 위하여 조촉매 $CeO_2$ 담지량에 영향을 파악하는 것이다. 3종의 천연가스산화촉매(NGOC)를 Fresh 조건과 $700^{\circ}C$ 12hr 열적 열화 조건으로 촉매를 제조한 후 유해가스 저감 성능을 평가하였다. $CeO_2$는 일반적으로 산화 환원반응성이 좋아 촉매활성에 좋다고 알려져 왔으며, 안정적인 물질인 $CH_4$와 NOx 저감 능력에 미치는 영향을 연구하는 것은 의의가 있다. 6wt% $CeO_2$가 담지된 Fresh $1Pt-3Pd-1Rh-3MgO-6CeO_2/(Al+Z)$ NGOC는 $CH_4$에 대한 선택도가 큰 Pd의 분산도가 제일 높았고 유해가스 저감 성능도 향상되었다. $700^{\circ}C$ 12hr 고온조건에서 내구성이 낮은 지지체 zeolite의 화합물 결정이 일부 파괴되면서 zeolite의 결정체인 $Al_2O_3$가 떨어져 나와 응집되었다. 6wt% $CeO_2$가 담지된 NGOC는 귀금속의 분산도 저하가 가장 작았고, $CeO_2$의 열적인 내구성으로 인하여 유해가스 저감 성능이 가장 높았다.

• 한국수소및신에너지학회논문집
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• 제28권2호
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• pp.174-180
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• 2017

Recently, the world faces the environmental problem such as air pollution due to harmful gas discharged from car and abnormal climate due to the green-house gases increased by the discharge of $CO_2$. Compressed Natural Gas (CNG), one of alternative for this problem, is less harmful, compared to the existing fossil fuel, as gaseous fuel, and less carbon in fuel ingredients and carbon dioxide generation rate relatively favorable more than the existing fuel. However, CNG fuel has the weakness of slow flame propagation speed and difficult fast burn. On the other hand, hydrogen does not include carbon in fuel ingredients, and does not discharge harmful gas such as CO and HC. Moreover, it has strength of quick burning velocity and ignition is possible with small ignition energy source and it's has wide Lean Flammability Limit. If using this hydrogen with CNG fuel, the characteristics of output and discharge gas is improved by the mixer's burning velocity improved, and, at the same time, is possible to have stable lean combustion with the reduction of $CO_2$ expected. Therefore, this research tries to identify the characteristics of engine and emission gas when mixing CNG fuel and hydrogen in each portion and burning them in spark igniting engine, and grasp the lean combustion limit and emission gas characteristics according and use it as the basic data of hydrogen-CNG premixed engine.

• 한국수소및신에너지학회논문집
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• 제27권4호
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• pp.357-364
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• 2016

Recently, the world faces the environmental problem such as air pollution due to harmful gas discharged from car and abnormal climate due to the green-house gases increased by the discharge of $CO_2$. Compressed Natural Gas (CNG), one of alternative for this problem, is less harmful, compared to the existing fossil fuel, as gaseous fuel, and less carbon in fuel ingredients and carbon dioxide generation rate relatively favorable more than the existing fuel. However, CNG fuel has the weakness of slow flame propagation speed and difficult fast burn. On the other hand, hydrogen does not include carbon in fuel ingredients, and does not discharge harmful gas such as CO and HC. Moreover, it has strength of quick burning velocity and ignition is possible with small ignition energy source and it's has wide Lean Flammability Limit. If using this hydrogen with CNG fuel, the characteristics of output and discharge gas is improved by the mixer's burning velocity improved, and, at the same time, is possible to have stable lean combustion with the reduction of $CO_2$ expected. Therefore, this research tries to identify the characteristics of engine and emission gas when mixing CNG fuel and hydrogen in each portion and burning them in spark igniting engine, and grasp the combustion stability and emission gas characteristics according and use it as the basic data of hydrogen-CNG premixed engine.

• 반도체디스플레이기술학회지
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• 제22권4호
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• pp.103-107
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• 2023

To solve the reliability problem of organic devices that are often used outdoors, multifunctional gas barriers that block reactive gases such as moisture and oxygen and reflect harmful light such as ultraviolet rays are needed. In this study, ALD nanolaminate-based optically functional n-DBR was developed to overcome the poor gas permeability of polymer substrates and protect organic devices from harmful light. n-DBR not only achieved a WVTR of 8.76 × 10^-6 g·m^-2·day^-1, but also showed a visible light transmittance of 94.3% and an ultraviolet ray blocking ability of 2.67%. In particular, n-DBR based on a nanolaminate structure maintained its permeability characteristics even in a high temperature and high humidity environment despite being used as a layer of Al₂O₃. This functional barrier Structure can not only be used as a functional encapsulation barrier for the reliability of organic devices, but can also be used as a tinting film for vehicles.

• 한국콘크리트학회:학술대회논문집
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• 한국콘크리트학회 2002년도 가을 학술발표회 논문집
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• pp.775-780
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• 2002

Sandwich panel made by foamed styrene and ployuretane has been used generally in the construction area because of the high thermal conductivity and light weight but they occur harmful gases to both bodies and environments in the high temperature over $50^{\circ}C$. So, the purpose of this study is to investigate the physical properties of light-weight panel using the non-structural lightweight aggregate as a part of the substitution of foamed styrene and ployuretane. This paper dealt with the effect of the addition of polymer dispersion such as SBR, St/BA-1 and St/BA-2 having polymer-cement ratio as 5, 10, 15% and the filling ratio of continuous void as 50, 60% on the strength of polymer-modified sandwich panel core. From the results, we could know that the compressive and flexural strength of the sandwich panel core using non-structural lightweight aggregate and polymer dispersion such as SBR, St/BA-1 and St/BA-2 tended to be increased with an increase in the polymer-cement ratio and the filling ratio of continuous void.