• Proceedings of the Korea Air Pollution Research Association Conference
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• 2003.05b
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• pp.405-406
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• 2003

분진여과시 형성되는 분진 케이크는 궁극적인 여과 성능을 좌우하며, 필터의 구조, 분진 입자의 형태나 크기, 분진농도, 여과속도 등에 의해 영향을 받는다 특히 필터의 표면 구조나 기공 크기는 여과 초기 단계의 케이크 층의 구조를 결정하며, 연속적인 여과시 초기 케이크 층은 다음에 쌓이는 케이크 형성과 비저항에 영향을 주므로 필터 medium 구조 또한 분진여과 과정에서 중요한 영향 요인이 된다. 본 연구에서는 필터 medium의 구조가 서로 다른 고온가스정화용 복합 세라믹 필터, metal fiber mat, 스테인레스 필터를 이용하여 분진농도와 여과속도를 변수로 하여 분진 여과 실험을 함으로써 각각의 필터에 대한 케이크 비저항과 기공율을 실험과 이론식으로부터 추정하였다. (중략)

• Proceedings of the Korea Air Pollution Research Association Conference
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• 2003.05b
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• pp.312-313
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• 2003

환경부 훈령 제500호 "비산먼지 저감대책 추진에 관한 업무처리 규정(2001.9.4)"에 따르면 "비산먼지"라 함은 일정한 배출구 없이 대기 중에 직접 배출되는 먼지를 말하며, 대기환경보전법에서는 비산먼지 발생사업의 신고 및 발생억제 의무를 규정하고 있다. 미국 국가배출목록(U.S. EPA, 2000)에 의하면 미세먼지(PM10) 배출량의 89%를 비산먼지가 차지하고 있으며 이러한 수치는 비산먼지가 대기질에 미치는 영향도가 어느 정도인지를 예시하고 있다. 한편 우리나라의 경우 현재 미세먼지 배출목록에서 비산먼지 항목이 누락되어 있기 때문에 효율적인 대기질 관리를 위해서는 전국 지역별 비산 먼지 배출 목록의 구축이 시급한 것으로 사료된다. (중략)

• Proceedings of the Korea Air Pollution Research Association Conference
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• 2003.05b
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• pp.39-40
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• 2003

레이저를 이용한 원격 분석 기술은 최근 들어 선진 여러 나라에서 지대한 관심을 보이며 급속한 발전을 이루고 있다. 특히, 라이다(LIDAR: Light Detection And Ranging)는 펄스형 레이저를 대기 중으로 조사하여 대기 중에 존재하는 공기 분자나 에어러솔에 의해 산란되는 신호를 수신하여 대기의 물리ㆍ화학적 성질을 규명하는 기술로 대기물질의 분석 감도, 공간분해능, 측정거리 면에서 탁월한 장점을 갖고 있다. 대개의 분석 장비들이 지엽적적인 공간 정보를 제공하는 반면, 라이다 장비는 레이저를 원하는 방향으로 조사함으로써 임의의 3 차원 공간에 대한 광역적인 정보를 실시간으로 제공할 수 있다(McDermid et al., 1990; McGee et al. 1991). (중략)

• The Korean Journal of Ecology
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• v.13 no.2
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• pp.131-142
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• 1990

From July 1, 1985 to June 30, pH values of precipitation in Seoul area were average 5.1 and acid rain which was lower than pH 5.5 showed a frequence of 70.7%. Seasonal changes appeared in pH values of annual precipitation in Seoul. The pH patterns of spring and autumn were generally less acid than that of summer and winter, and snowfall pH was lower than rainfall. The beginning rainfall in Seoul was neutral because of alkali dust in the atmosphere. As times went on, rainfall pH was gradually low and after 1 to 2 hours, showed a steady state. On the surface soil precipitation was neutralized by soil buffering capacity.

• Journal of the Korean Society for Advanced Composite Structures
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• v.6 no.3
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• pp.50-61
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• 2015

This paper presents on the structural behavior of the the methyl methacrylate monomer (MMA) double wide flanged the glass fiber-reinforced polymer(GFRP) pipe composite structures for the manhole raise. The evaluation of structural performance on this composite structure was conducted by the axial load, fatigue load, and ultimate load test. The assessment indicates that the MMA double wide flanged GFRP pipe composite structures was confirmed safety, durability and reliability in result as expected. It was found that this composite structure was able to short working times to around 30-50% and construction costs to around 10-23% with compare other construction methods. Also, environmental pollution and civil complaints will be prevented because there will be no longer any noises, vibrations, dust, or construction wastes.

• Journal of Korean Society for Atmospheric Environment
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• v.2 no.2
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• pp.66-74
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• 1986

Rain samples were collected at 10 sites in the Seoul area during the period of August through November, 1985. THe concentrations of the major cations $(H^+, Ca^{++}, MG^{++}, Na^+, K^+, NH_4^+)$ and the major anions $(SO_4^=, NO_3^-, Cl^-)$ were measured to characterize the main sources of chemical ions in rainwater. Correlating concentrations of ions to pH, calculated coefficients ranged from 0.1485 to 0/4296. Sulfate shows the largest coefficient indicating that sulfate is more closely associated with hydrogen ion than other ions. This may suggest that sulfuric acid contributes more to the acidity of rainwater in Seoul. It appears that the major chemicals measured in rainwater are from the anthropogenic sources of air pollution. Predominant chemicals are acidic at the Guro-, the Sinseol-, the Yangnam-, and the Ssangmun-dong with sulfate being the most predominant. IT also indicates that alkaline substances resulting from soil and dust have a significant effect on pH values of rainwater by neutralizing actions. According to Granat-model analysis, it is estimated that the relative contributions to the rainwater acidity in Seoul are 84% from sulfuric acid, 8% from nitric acid and 8% from hydrochloric acid.

• Proceedings of the KIEE Conference
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• 2005.07d
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• pp.2600-2602
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• 2005

An electric precipitator in a thermal electric power plant is essential equipment for preventing air environment pollution. However, it is difficult for the existing control systems to make efficient effects on dust collection. This is because AVC and ERC consist of independent, separate systems in the existing systems. To solve this problem, we developed an intelligent distributed control system, which makes optimal control possible through connection operations between the control systems. In this paper, we analyzed system performance and fly ash reduction effects through the developed system structure, development contents and its actual application to power plant.

• International Journal of Advanced Culture Technology
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• v.8 no.3
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• pp.275-279
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• 2020

Due to the recent rapid industrialization worldwide, the number of pediatric asthma patients is increasing. And the fine dust containing heavy metals is linked to the characteristics of high toxic lead due to the increase heating in factory operation and automobile driving. It is the reason of arsenic increasing. In the treatment of pediatric asthma patients, drug administration, oral drug entry, and HMPC (Home Management Plan of Care) are used. In this paper, we analyze the relationship between the onset of asthma and the method of prescription for specific childhood asthma in the United States using EM (Expectation Maximization) and MDL (Minimum Description Length) algorithms. And the association is also analyzed by comparing the nature of specific congestion between the past prevalence of digestive asthma and the recent prevalence of environmental pollution.

• Proceedings of the KSR Conference
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• 2007.05a
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• pp.1558-1563
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• 2007

The air pollution by the diesel locomotives has become serious environmental concern because the emission gases are exhausted without any further treatment. Recently, the public interest on the air pollutants emission reduction technology is increasing due to the establishment of 'Metropolitan Air Quality Preservative Law' and the regulation of local governments on the urban air quality. In this study, we measured the concentration of particulate matters and gaseous pollutants by using a scanning mobility particle sizer, a dust spectrometer, and a stack sampler upon various engine load condition. The results show that the amount of emitted air pollutants increased upon the increase of engine power. The development of new technology to reduce the air pollutants emission is urgently required.

• Proceedings of the KSR Conference
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• 2007.05a
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• pp.864-874
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• 2007

Suspension insulator in Catenary Trolley Wire Systems must have two characteristics, electric insulation and mechanical endurance. Because suspension insulator is used in supporting and insulating position between power supply parts and earth conducted supporting parts. The insulator's electric characteristics can be influenced by surface pollution and damage from the environment such as humidity, dust, smoke, salt. etc. And, the insulating parts can be electrically short. These electrically damaged insulator can cause serious accidents that have far-reaching effect. So appropriate management basis of suspension insulator is needed. And we present appropriate cleaning and the changing period of suspension insulator on the basis of actual data.