• 자동차안전학회지
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• 제10권3호
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• pp.27-31
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• 2018

The People have a bad perception about diesel vehicle because of serious air pollution, increase fine dust and global vehicle company's diesel gate. Starting the project in 2005, Ministry of Environment has been supporting that is exhaust gas reduction devices (DPF) on diesel vehicles in the metropolitan area. During the period of 2017.01.01 to 2017.12.31, 10,030 diesel vehicles installed exhaust gas reduction devices (DPF). Among them, 9,921 diesel vehicles that they have sufficient data for analysis were analyzed amount of particulate matter reduction before and after exhaust gas reduction devices (DPF) was installed. Opacity smoke meter measures the concentration of particulate matter. So concentration of particulate matter was converted into a mass unit, and then calculated the total amount of reduced particulate matter. It was estimated that social benefits is costs required to remove it from the total amount of particulate matter.

• 한국자동차공학회논문집
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• 제6권2호
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• pp.168-177
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• 1998

The effects of the regeneration parameters such as inlet gas temperature, space velocity, oxygen concentration of the exhaust gas, and initial particulate loading on the oxidation of the particulate inside ceramic cordierite filter have been investigated through an engine experiment. As the inlet gas temperature increases, the remarkable filter temperature occurs owing to the rapid combustion rate. Though the higher space velocity affirms the safe regeneration, it also requires much fuel consumption of the burner. For that reason, the space velocity should be compromised considering the fuel economy. The excessive accumulation of the particulate may cause undesirable regeneration temperatures inside filer even under the optimized regeneration condition. The inlet gas temperature should be selected to overcome the variation of the oxygen concentration which is inherent feature of the diesel engine. It is the most important factor in the regeneration control techniques.

• 대한예방한의학회지
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• 제22권1호
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• pp.69-80
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• 2018

Objectives : This paper examines the effects of Particulate Matter on human bodies and the possibility of treating them with Chinese or Korean medicines. Methods : This paper categorizes the diseases caused by Particulate Matter, as well as the causes, pathology, prevention methods, and effectiveness of treatments by Chinese and Korean medicines. Based on these results, it analyzes whether such diseases can be managed by Chinese and Korean medicine. Results : Particulate Matter is known to affect respiratory organs, skin, circulatory system, nervous system, gestational diabetes, and other parts of the human body. While studies show evidence that treatments by Chinese and Korean medicines can reduce symptoms of some diseases and improve bodily functions that are damaged by Particulate Matter, there is no statistically significant evidence that they can provide fundamental treatments nor treat irreversible damages. Conclusion : Currently, there is no definite evidence that Chinese and Korean medicine can treat symptoms and diseases caused by Particulate Matter. Therefore, some Korean medicine doctors' arguments that Korean medicine is effective in treating such diseases are problematic, and thus, there is a need for much research in this field.

• Archives of Plastic Surgery
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• 제38권3호
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• pp.222-227
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• 2011

Purpose: Autogenous particulate bone grafting is a type of autogenous bone graft that consists of small particles of cortical and cancellous bone. Autogenous particulate bone grafting has been used for calvarial bone defect after calvarial defect of craniosynostosis and prevention of temporal depression after fronto-orbital advancement. The results were followed up and studied for effectiveness of autogenous calvarial particulate bone grafting. Methods: Cranial vault remodeling and fronto-orbital advancement was performed for six craniosynostosis patient from August 2005 to October 2007. Autogenous particulate bone grafting was harvested from endocortex of separated cranial vault and if insufficient, from extocortex of occipital region using Hudson brace & D'Errico craniotomy bit and was grafted on the calvarial bone defect of cranial vault and temporal hollow. Fibrin glues were added to the harvested particulated bone for adherence and shaping of paticles. Results: Autogenous particulate bone grafting was followed-up at least longer than I year. The calvarial bony defects following primary cranial remodeling were successfully covered and postoperative temporal depressions after fronto-orbital advancement were also well prevented by grafted particulated bone. Conclusion: Autogenous calvarial particulate bone graft can be harvested in infants and young children with minimal donor site morbidity. It effectively heals cranial defects in children and during fronto-orbital advancement reduces the prevalence of osseous defects independent of patient age. It's easy and effective method of reconstruction of calvarial defect.

• 한국의류학회지
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• 제36권11호
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• pp.1237-1245
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• 2012

The effect of hydrophilicity and hydrophobicity of PET fabric on the detergency of particulate soil were investigated as functions of the concentration of hydrophilic and hydrophobic chemicals, surfactant concentration, ionic strength, adhesion and removal time, and pH. The detergency of the particulate soil was determined by the adhesion of particles to and their removal from fabric, the PET fabric and ${\alpha}-Fe_2O_3$ were used as textile materials and for the model of particulate soil, respectively. The hydrophilic and hydrophobic finish for PET fabric was treated with a polyester, silicone and fluorine organic compound of resin respectively. The adhesion of particulate soil to fabric treated with hydrophobic chemicals were slightly higher but its removal from fabric treated with hydrophobic chemicals was largely higher than fabric treated with a hydrophilic chemical regardless of solution conditions such as the concentration of hydrophilic and hydrophobic chemicals, surfactant concentration, ionic strength, adhesion and removal time, and pH. Therefore, hydrophobic treatment for fabric had a more positive effect than the hydrophilic treatment on the detergency of particulate soil.

• Environmental Engineering Research
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• 제19권3호
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• pp.215-221
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• 2014

Nano-sized $TiO_2$ particles were produced by a premixed flame aerosol reactor, and they were immobilized on a mesh-type substrate in form of particulate film. The reactor made it possible maintaining the original particulate characteristics determined in the flame synthetic process. The particulate morphology and crystalline phase were not changed until the particulate were finally coated on the substrate, which resulted in the better performance of the photocatalytic conversion of the volatile organic compounds (VOCs) in the ultraviolet $(UV)-TiO_2$ system. In the flame aerosol reactor, the various specific surface areas and the anatase weight fractions of the synthesized particles were obtained by manipulating the parameters in the combustion process. The performance of the $TiO_2$ particulate films was evaluated for the destruction of the VOCs under the various UV irradiation conditions. The decomposition rates of benzene and formaldehyde under the irradiation of UV-C of 254 nm in wavelength were evaluated to check the performance of $TiO_2$ film layer to be applied in air quality control system.

• 자동차안전학회지
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• 제11권1호
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• pp.36-39
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• 2019

The particulate matter that was emitted always come up by atmospheric environmental problem. Running on the road vehicles must have regular inspection at regular period and make sure the emissions of exhaust gases exceed the legal standards. Emission test for the atmospheric environment, but it is not free from the particulate matter. Currently, emission test of vehicle inspection is divided into regular inspection and close inspection. Regular inspection and close inspection differ not only the method of emission test, but also the facility standards that must have for this inspection. According to the "Regulations on the Implementation of Comprehensive vehicle Inspection, etc.", close inspection must have trapping device that is trap particulate matter by emission test to vehicle. However, regular inspection is different. Regular inspection do not specify any criteria for trapping facilities. Therefore, this study is confirm how to prevent the emission of particulate matter to the atmosphere during the year when mandatory trapping facilities are required to trapped particulate matter in the regular inspection.

• 한국환경과학회지
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• 제32권2호
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• pp.131-137
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• 2023

Filter and microbalance sensitivity in measuring fine particulate matter mass is greatly influenced by particulate properties and environmental factors. Temperature and humidity control inside a measuring chamber with a microbalance, and neutralization of static charges on filters are essential for consistent filter weighing. Commercial weighing chambers are expensive with a unit price of tens of millions won. This study developed an inexpensive weighing chamber for weighing fine particulate matter and evaluatedits weighing performance. A microbalance with 1 ㎍ precision was used to measure the weight of a filter. The microbalance was set in a transparent acrylic enclosure (100 × 60 × 65 cm³) equipped with temperature and humidity control equipments. Weighing performance of the chamber was examined using Teflon filters with or without different particulate sample types. Temperature and humidity were maintained at approximately 23.2±1.2 ℃ and 36.2±1.8℃ for 8 days, respectively.

• 한국지구과학회지
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• 제36권1호
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• pp.125-135
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• 2015

이 연구에서는 중등학교에서 사용할 수 있는 미세먼지 포집 장치를 직접 설계 및 제작하고 이를 통해 미세먼지에 포함된 중금속 및 미생물을 분석하는 활동이 가능한지 여부를 탐색하고자 한다. 중등학교 현장의 과학 탐구활동을 위해 청주지역에서 미세먼지를 포집하는 방법과 그 속에 포함된 중금속 및 미생물을 분석하였다. 미세먼지의 포집장소는 청주지역 대학교의 4층 건물 옥상에서 포집하였다. 모터 펌프, 인넷, 지름 $1.0{\mu}m$ 테프론필터, 필터 홀더 등을 이용하여 포집장치를 제작하였다. 이 포집장치를 이용한 미세먼지 포집은 2013년 12월-2014년 6월까지 진행하였다. 포집한 미세먼지의 중금속 성분과 미생물 포함 여부를 분석하였다. 중국에서 날아온 미세먼지 속에는 Cu, Zn, Cd, Ni, Pb 등인위적인 오염물질로 판단되는 중금속 성분이 국내 기원 미세먼지 보다 많았다. 더 나아가, 미세먼지 속에는 중금속 뿐만 아니라, 곰팡이나 세균같은 미생물도 다량 포함하고 있었다. 이 연구는 미세먼지가 중금속 뿐만아니라 미생물도 포함하고 있으므로, 이에 대한 체계적인 연구와 모니터링이 필요함을 시사한다고 할 수 있다. 또한, 이 연구는 중등학교 과학실험의 사례로 제공될 수 있다.

• 한국연소학회:학술대회논문집
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• 한국연소학회 2014년도 제49회 KOSCO SYMPOSIUM 초록집
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• pp.347-348
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• 2014

After-treatment system for gasoline direct injection engines should be considered due to the regulation standard for particle number emitted from spark ignition engine vehicles. A metal foam particulate filter, which is thought to be more proper for gasoline engines for its unique filtration and heat resistance characteristics, has been evaluated via engine dynamometer tests.