• Journal of Preventive Medicine and Public Health
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• v.26 no.1 s.41
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• pp.126-146
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• 1993

To understand the possible hazards to health from the environmental pollution in Korea, the articles reported in 16 daily newspapers were collected and analysed. From 1980 to 1991, ninety three cases were reported. Statistics show that, during the last 2 years, there has been a remarkable increases of health problems reported. The main sources of pollution were plants and the transportation facilities. Except the noise, the exact causative factors were, for the most part, not clealy described. Although many residents complained of neurological symptoms, the exact effects on health were not clearly investigated. The responses of the residents were diverse in the contents of the demand and the method of its pushing, however, the government did not show immediate and consistent counterplans.

• Transactions of the Korean Society of Mechanical Engineers A
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• v.35 no.11
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• pp.1471-1476
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• 2011

The catalytic converter in the front part of an automobile's exhaust system converts toxic exhaust gas into nontoxic gas. The substrate in the central part of the converter has a circular or oval-shaped cross section and fine lattice-shaped walls. In the canning process, the substrate is wrapped in mats and inserted into a can. During this process, mat pressure is induced, which may cause brittle fracturing in the substrate. In this paper, a finite element program for determining the mat pressure distribution was developed to avoid these fractures. The program was created in Microsoft EXCEL, so the input and output procedures are relatively simple. It was assumed that the substrate is rigid, the mat is material nonlinear, and the can is linear elastic. The can is modeled as a beam element to resist both bending and uniform tension/compression. The number of elements is fixed to 35, and the number of iterations, to 20. The solutions are compared to ABAQUS solutions and found to be in good agreement.

• Journal of the Korean Chemical Society
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• v.9 no.3
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• pp.116-120
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• 1965

The degree of atmospheric pollution from automobile engine exhausts has been measured at 1-ga, Eulchiro, Jung-ku, one of the heaviest traffic junctions in Seoul. By determining the concentrations of Pb, $SO_2, NO_2, NO, CO \;and\; CO_2$ in atmospheric air measured are as follows: Pb, $21{\sim}2 {\mu]g./m^3.;\;SO_2,\;0.33{\sim}0.001\;ppm.;\;NO_2,$ $0.20{\sim}< 0.01\;ppm.;\;NO,\;1.30{\sim}0.02\;ppm.;\;CO,\;40{\sim}<\;5ppm$.; and $CO_2,\;0.040{\sim}0.034%$. The mean concentrations determined are as follows: Pb, $11 {\mu}g./m^3.; SO_2, 0.08 ppm.; NO_2,$ 0.09 ppm.; NO, 0.37 ppm.; CO, 16 ppm. and $CO_2,$ 0.038%. Generally, the concentrations of Pb, $NO_2, NO, CO\; and\; CO_2$ are approximately proportional to the traffic density, vehicles passing per hour.

• 보존과학연구
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• s.17
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• pp.65-99
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• 1996

We exanmined the each effect of $NO_2$ and $SO_2$gas, the maincomponets of air pollutants, on the deterioration of 6 organic materials with Gasexposure cabinet. The organic materials were used 2 kind of papers(Korean paper, Oldbook paper) and 4 kind of textiles (Cotton, Silk, Hemp, ramie) in gas exposure experiments. In order to know how to change of physical conditions, the materials were exposed to 2000, 1000 ppm. h of $SO_2$dose, to 100 ppm. h of $NO_2$ dose at 65% RH. The color difference, tensile strength, elongation coeffient, mass reduction and fabric status of each materials were discussed the following below.1. The color difference of cotton and hemp was larger than that of silk and ramie in the presence of $SO_2$ gas. and the color difference of korean paper was less than that of the textile materials in the presence of $SO_2$ gas.2. The tensile strength of cotton fell suddenly at 100ppm.h of $SO_2$ dose and even became 56% of the unexposed cotton.3. The weight of 6 materials began to decrease in the presence of $SO_2$ gas.4. The tensile strength and elongation of the materials tended to decrease at 12.5ppm.h of $NO_2$ especially silk was the strongest tendency to decrease.5. Cotton, hemp and ramie were influenced by $SO_2$ gas more than by $NO_2$, but silk were influenced by $NO_2$ more thang by $SO_2$ at 10ppm.h of each noxious gas.

• Journal of the Korea Institute of Building Construction
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• v.16 no.2
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• pp.117-123
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• 2016

Glass wool is a material that has been used as a heat insulator in various fields including construction industry. Since it is a nonflammable material, it does not generate toxic gases on fire, and thus public agencies recommend using glass wool as a heat insulator instead of other organic materials. However, repeated drying and wetting cycles can deteriorate thermal property of glass wool due to the shrinkage and reduction in pore size. For this reason, it needs to be replaced periodically, and waste materials are generated. This research aims to utilize waste glass wool as additives for increasing mechanical properties of concrete. According to the experimental results, it was found that glass wool has weak pozzolanic activity, and beneficial effect on both compressive and flexural strength. The optimum amount found in this experimental work was 0.5% volumetric addition to the concrete.

• Journal of Advanced Marine Engineering and Technology
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• v.39 no.4
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• pp.381-386
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• 2015

Environmental pollution and alternative energy has attracted increasing interest. The use of diesel engines is expected to increase in the world owing to their fuel economy. The problem of air pollution emissions from marine engines is causing a major concern in many areas. An alternative fuel was introduced as an environmentally friendly fuel to reduce the toxic emissions from conventional fossil fuels. Biodiesel fuel, which is a renewable energy is highlighted as environmentally friendly energy. This energy can be operated in regular diesel engines when it is blended with invariable ratios without making changes. In this study, a bio-diesel fuel was produced from waste cooking oil and applied to a marine diesel engine to examine the effects on the characteristics of combustion. Waste cooking oil contains a high cetane number and viscosity component, a low carbon and oxygen content. As a result, the brake specific fuel consumption was increased, and the cylinder pressure, rate pressure rise and rate of heat release were decreased.

• Journal of the Korean Society of Propulsion Engineers
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• v.20 no.2
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• pp.31-38
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• 2016

Most of propellants that is used widely in the world release toxic gases such as methane gas and carbon dioxide during combustion which are noxious to the environment. This study established a synthetic process of a high nitrogen containing derivative of triazole, 4,5-bis(azidomethyl)-methyl-1,2,3-triazole (DAMTR), which can be applied as energetic plasticizer to environmental concerns. Also, the compound was characterized by NMR, IR spectroscopy, and physical properties such as glass transition temperature, melting point, decomposition temperature, density, impact sensitivity, viscosity and volatility were measured. In addition, the heats of formation (${\Delta}H_f$) and detonation properties (pressure and velocity) of DAMTR were calculated using Gaussian 09 and EXPLO5 programs.

• Proceedings of the Korean Society of Dyers and Finishers Conference
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• 2011.11a
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• pp.30-30
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• 2011

산업화 과정에 방출된 할로겐 화합물 및 프레온 가스가 오존층을 파괴하면서 많은 양의 자외선이 지표에 도달하여 생태계에 적지 않은 영향을 끼치고 있다. 자외선은 살균, 소독작용 및 Vitamin D 합성을 위해 생명체에 필수적이지만 과다할 경우 색소침착, 피부노화, 피부암 발생, 백내장의 증가, 면역기능저하 등의 피해를 준다. 자외선은 파장 영역에 따라 UV-A(장파장 자외선), UV-B(중파장 자외선)및 UV-C(단파장 자외선)으로 나뉜다. 이 중 인체에 가장 유해한 것으로 알려진 단파장의 UV-C는 파장이 짧아 침투력이 미약해 오존층과 성층권에서 대부분 흡수되므로 생물학적으로 큰 의미는 없다. 그러나 자외선 중 UV-B와 UV-A 영역의 자외선은 인체에 영향을 가장 많이 미치므로 이들 영역의 자외선을 차단하는 것이 필요하다. Vitamin C는 아스코르브산(ascorbic acid)이라고도 불리며 미백효과, 주름 개선, 자외선 차단 및 항산화 작용을 하지만 섬유가공 시 Vitamin C는 쉽게 산화되며 세탁 내구성이 떨어지기 때문에 가교제를 필요로 한다. Vitamin C를 이용하여 자외선 차단성 섬유제품을 개발하기 위해, 포름알데히드를 유리하지 않는 폴리카르복시산 가교제 중 하나인 Citric Acid(CA)를 사용하여 고온에서 면직물에 처리했을 때 에스테르 형 가교를 형성하여 내세탁성을 가질 수 있었다. 자외선 차단 효과를 알아보기 위하여 KS K 0850 섬유제품의 자외선 차단율 및 차단지수 시험방법으로 평가하였다.

• Korea journal of population studies
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• v.13 no.1
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• pp.51-80
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• 1990

한국의 사망력은 높은 수준의 성별 사망력 차이와 중년 남성의 급격한 사망력 상승을 그 구조적 특성으로 하고 있는데, 이러한 한국인 사망력 구조의 특이성은 직접적으로는 사망원인의 성별, 년령별 차별적 역활에 기인하며 간접적으로는 이들 원인의 차별성을 초래하는것으로 추정되는 경제개발기간동안의 사회, 경제 및 공공정책상의 변화 및 생활습관의 차이에서 기인된다고 보아진다. 본 연구에서는 이들 차이를 결과짓는 여러 요인들을 중심으로 한국인의 사망력 구조상에서 나타난 년령별 및 성별특성을 분석하는데 그 주요점을 두었다. 1985년 경제기획원 조사통계과에 의해 집계된 사망원인통계자료는를 활용하여 한국인의 사망력 구조의 특성을 사망원인과 관련시켜 연구분석한 결과는 다음과 같이 종합될수 있다. 첫째, 40대 이후 남성의 높은 사망력에 의거한 요인들은 뇌혈관질환, 고혈압성질환, 암질환 및 기지 심질환 및 간의 악성신생물 순으로 중요하게 나타났다. 둘째, 0세에서의 남녀간의 기득개념의 차이는 차이는 초년 또는 청년층에서의 남녀간의 사망력 차이에서 보다는 40대 이상의 중장년층에서의 남녀간의 사망력 차이에서 비롯되었으며, 뇌혈관 질환, 악성간질환 및 고혈압성 질환, 간의 악성 신생물,및 기타 심질환 및 간의 악성 신생물 질환들이 중장년층에서의 남녀간의 사망력 차이를 결정하는데 주역활을 하고 있는 것으로 나타났다. 세째, 위의 년령간의 및 남녀간의 사망력 수준의 차이를 결정짓는 주요한 사회적 간접요인들로는 첫째, 사회.경제개발과 함께 이어 병행되어온 보건정책들이 즈로 어린이 또는 여성에 편향된 결과 였으며, 둘째,환경적 요소로서 중년 남성들의 Social stress, 운동부족과 관련된 질병들과 공해, 먼지, 유해화학물 가스 등 산업재회와 관련된 질병들에 의한 사망률이 높으며, 세째, 행위적 요소로서 음주와 흡연과 관련된 질병들에 의한 중년 남성의 사망률이 높은것들로 요약될수 있다. 중년 남성의 높은 사망률은 기술적,사회적 경험이 축적된 노동력의 상실로서 국가적 손실이 크며, 고 년령층 인구의 구조적 측면에서도 성의 불균등을 초래하여 미혼 여성의 증가등 사회적인 기반문제의 주요한 요인이 되므로서 그 중요성은 지대하다고 할수 있겠다. 그러므로 이 문제는 국가적 사회적 차원에서 해결이 시급하며 그 해결책으로는 지금 까지 도외시 되어 왔던 중년 남성의 건강을 위한 프로젝트의 실지와 함께 이들에게 노출되어 왔던 운동 부족, 사회적 스트레스 및 산업재회의 해소 내지 제거에 대한 방안들이 연구 되어야 하겠다. 한편 음주 및 흡연등의 개인행위적 습관의 개선을 위한 사회 계몽활동의 추진 및 건전한 스트레스 해결책의 개발이 중요하다고 하겠다.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.18 no.4
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• pp.711-717
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• 2017

Startability and harmful emissions are the main issues in diesel engine development under cold conditions. The characteristics of combustion with multiple injection were investigated under cold start conditions. For quantitative analysis, the in-chamber pressure profile was measured and combustion visualization using direct imaging was accomplished. With multiple injection, the peak in-chamber pressure and heat release rate were increased compared to single injection. In addition, the period of flame luminosity detection was shortened using multiple injection. Combustion by main injection was improved with an increase in heat released by pilot combustion when the pilot injection quantity was increased. Finally, an increase in injection pressure also showed the possibility of combustion improvement. On the other hand, an increase of in the pilot injection quantity and injection pressure can cause an increase in harmful emissions, such as HC and CO due to wall wetting. Therefore, more sensitive calibration will be needed when applying a multiple injection strategy under cold start conditions.