• 제목/요약/키워드: Environment Protection Agency

검색결과 215건 처리시간 0.022초

아연(Zn)희생양극 등가전위에서 부식피로균열 진전특성에 관한 연구 (Evaluation of Corrosion Fatigue Crack Propagation Characteristics at Equivalent Potential of Zinc Sacrificial Anode)

  • 김원범
    • 문화기술의 융합
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    • 제10권1호
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    • pp.363-368
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    • 2024
  • 선박, 해양구조물 또는 해상풍력 발전설비 하부구조와 같이 해양환경에서 사용되는 강구조물은 부식이 쉽게 발생한다. 본 연구에서는 실험을 통하여 희생전극으로 많이 사용되는 아연전극의 방식전위와 동등한 -1050mV vs. SCE에서 환경하중에 기인하는 부식피로균열 진전특성에 대하여 고찰하였다. 이를 위하여 본 연구에서는 -1050mV vs. SCE의 음극방식이 해수환경중의 피로균열 진전에 미치는 영향에 대해 합성해수중에서 파랑주기를 고려하여 실험적 고찰을 실시하였다. 음극방식에 의한 방식법은 부식을 차단하지만 과도한 방식은 화학반응에 의하여 수소를 발생시키며, 또한 석회질퇴적물을 발생시킨다. 피로균열진전율은 실험초기에는 해수부식환경하에서의 진전율보다 빠른구간이 나타났다. 그리고 균열길이가 증가하여 응력확대계수 K가 커질수록 균열의 진전율은 해수중의 피로균열진전율보다 느려지는 현상이 나타났다. 그러나 대기중의 균열진전속도보다는 항상 빠른 진전속도를 나타내었다.

다중 공중 이동/검증 링크에서의 MLP-A 알고리즘 및 구현 (MLP-A(Multi Link Protection for Airborne Network Verifying) algorithms and implementation in multiple air mobile/verification links)

  • 윤종택;정형진;김용이;전준석;박주만;주태환;고민선
    • 한국정보통신학회논문지
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    • 제26권3호
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    • pp.422-429
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    • 2022
  • 본 논문에서는 현재 기술 개발 과제로 진행 중인 다중 공중 이동 및 검증을 위한 다채널 공중 중계 장치와 다수의 임무 장치로 구성된 네트워크 시스템 기반 기저대역부와 RF부간의 중간주파수 전송 신호 레벨을 기준 신호 레벨로 일정하게 유지하도록 하고, 상대방의 수신 입력 범위를 고려하여 단거리 장거리 무선 통신 환경 변화에도 RF부 내의 송수신 회로 상의 신호 탐지와 자동이득제어, 자동출력제어 기능을 통해 신호가 안정되고 신뢰성 있게 전송되도록 하는 다중 링크 보호, MLP-A 알고리즘을 제시한다. 그리고, MLP-A 알고리즘이 적용된 RF부를 설계, 제작, 구현하고 다중 공중 이동 및 검증 네트워크 구성으로 거리 산출 수식을 적용하여 단거리, 장거리 무선 환경을 고려한 실험 및 분석을 수행하였다. 이를 통해 안정적이고 신뢰성 있는 RF 통신 시스템 운용이 가능함을 확인하였다.

인천항의 대기오염물질 배출량 산정 연구 (A Study on Estimating Air Pullution in the Port of Incheon)

  • 이정욱;이향숙
    • 한국항만경제학회지
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    • 제37권1호
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    • pp.143-157
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    • 2021
  • 세계보건기구(World Health Organization, WHO), 경제개발협력기구(Organization for Economic Cooperation and Development, OECD)등 국제기구 및 주요 선진국에서는 대기오염의 심각성을 인지하고 있다. 또한 국제해사기구(International Maritime Organization, IMO) 등의 국제기구에서도 선박에서 발생하는 대기오염을 감소시키 위해 다양한 규제를 시행하고 있다. 이러한 국제적인 흐름에 따라 국내에서도 「항만지역등 대기질 개선에 관한 특별법」(이하 특별법)을 제정하며, 항만에서 기인하는 대기오염을 감소시키려는 노력을 보이고 있다. 특별법의 목적은 항만지역 등의 대기질을 개선하기 위하여 종합적인 시책을 추진하는 것이다. 본 연구는 이러한 정책적 움직임에 맞추어 항만에서 기인하는 대기오염물질 배출원별 배출량을 파악하여 정책의 우선순위 설정에 기초자료를 마련하고자 하였다. 이를 위해 선박, 차량, 하역장비, 하역/야적재비산먼지, 도로재비산먼지, 철도 6개 부문으로 분류하여 분석을 시행하였으며, 유럽환경청(European Environment Agency, EEA)과 미국환경보호국(United States Environmental Protection Agency, EPA)에서 제시하는 방법론을 이용하였다. 분석대상 오염물질은 일산화탄소(CO), 질소산화물(NOX), 황산화물(SOX), 총부유물질(TSP), 미세먼지 및 초미세먼지(PM10, PM2.5), 암모니아(NH3)를 대상으로 분석하였다. 분석결과 총 7,122톤의 배출량이 발생한 것으로 나타났다. 물질별로는 NOX가 5,084톤으로 가장많은 비중을 차지하는 것으로 나타났으며, 다음으로 CO(984톤), SOx(530톤), TSP(335톤)의 순으로 나타났다. 배출원 별로는 선박이 4,107톤으로써 가장 많은 비중을 차지하며 다음으로 차량이 2,622톤으로써 높은 배출량을 보였다. 이는 각각 전체 배출량의 57.6%와 36.8%로써 항만 대기오염을 유발하는 주요원인으로 판명되어 이들 배출원에 대한 대책이 필요함을 시사하였다.

Exploration on the Development and Characteristics of Composites Painting in the Contemporary Art Ecology

  • Wang, Jingjing
    • International Journal of Advanced Culture Technology
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    • 제10권4호
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    • pp.337-344
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    • 2022
  • The ecological expression of art in modern society takes the harmonious developmental relationship between man and nature as an element and combines it with the various manifestations of painting as an expression of ecological artistic development. The necessary relationship for the harmonious development of nature is accurately articulated, and the ecological changes in people are expressed in integrated materials that inspire human reflection. In the pursuit of material pleasures, mankind is neglectful and indifferent to the environment. The development of composite painting in art and ecology is a process that more reveres the harmony between man and nature as well as satisfying the creative value of the work. After systematic evaluation and research, people have engaged in various structural forms of composite art painting development in the long history of art development, focusing on the integration of environmental and ecological culture.In the process of nature education going through development, the comprehensive practical development of nature education is enhanced and efforts are made to feel new ecological art ideas and new ways of valuing environmental protection. In this paper, an observational study of eco-art will be carried out, starting from the theory of hierarchical division and analyzing the contradictory relationship between man and nature. Recognize nature, understand it and feel it through eco-art painting. The analysis of the contradictory relationship between man and nature is combined with the identification of various types of information that give value to the environmental protection public, and the combination of ecological painting and nature art to achieve an upgrade of the environmental protection idea of the value of painting.

Estimation of 222Rn Concentration in the Lower Troposphere during Precipitation Using Wet Scavenging Model for its Decay Products

  • Takeyasu, Masanori;Takeishi, Minoru
    • Asian Journal of Atmospheric Environment
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    • 제4권1호
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    • pp.20-25
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    • 2010
  • The gaseous $^{222}Rn$ concentration at the level of clouds was estimated by using the wet scavenging model of its decay products with the observed data of environmental radiation at the ground. And the origin of the $^{222}Rn$ was also discussed. The estimation was done for a precipitation event on Dec. 26-27, 2003, when a large increase of the radiation was observed in Tokai-mura in Ibaraki, Japan. From a backward trajectory analysis, the origin of $^{222}Rn$ atoms for that event was traced back to the northeastern part of China, and it was expected that the large amount of $^{222}Rn$ emitted in the northeastern part of China was transported to Tokai-mura by the Eurasian continental air mass.

Heavy metals and VOCs contamination of urban Broundwaters in Seoul, Korea

  • Park, Seong-Sook;Yun, Seong-Taek;Park, Byoung-Young;Yu, Soon-Young
    • 한국지하수토양환경학회:학술대회논문집
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    • 한국지하수토양환경학회 2002년도 추계학술발표회
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    • pp.291-295
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    • 2002
  • We measured the concentrations of heavy metals and VOCs in groundwaters (N=38) in Seoul. The comparison of our data with U.S. Environmental Protection Agency's Maximum Contaminant Levels for Drinking Water and with the Korean Drinking Water Standards shows that most of the metals except for Fe and Mn do not exceed the levels. However, the concentrations of most heavy metals (esp., Zn, Cu, Cr, Ni) tend to increase in residential and industrialized areas. The examination of the metal speciation using Anodic Stripping Voltammetry (ASV) and TOC analyzer Indicates that large amounts of Zn occur as labile metal fraction, whereas Cu occurs as non- labile forms at many sites, possibly due to its tendency to be adsorbed onto inorganic colloidal particles to form electroinactive species in groundwater. The most frequently existed VOCs in Seoul groundwaters are trichloroethylene and tetrachloroethylene, especially in agricultural, industrial, and high traffic areas.

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Managing Soil Contamination in the United States: Policy and Practice

  • Small, Matthew C.
    • 한국지하수토양환경학회:학술대회논문집
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    • 한국지하수토양환경학회 2003년도 International Symposium
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    • pp.58-69
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    • 2003
  • Soil contamination in the United States is managed using a risk-based decision making process. In other words, we don't ask, 'how much soil contamination can be cleaned up\ulcorner' Instead we ask, 'how much contamination can be safely left in place\ulcorner' The determination of 'safe' levels of contamination is based upon the potential for exposure and the toxicity of the contaminants of concern in soil. Potential for exposure is determined by evaluating potential exposure pathways from source to receptor given current or reasonably anticipated land use. Soil cleanup goals are then calculated for any complete exposure pathways based upon toxicity and the route of exposure. In some cases, institutional or engineering controls are also used to limit the potential for exposure. In order to prevent a continuous degradation of environmental quality, risk-based cleanup approaches must be combined with strong contamination prevention programs. In addition, alternative risk management approaches should be incorporated into an overall risk reduction strategy.erall risk reduction strategy.

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일부 제조업 여성근로자의 근로환경에 관한 연구 (Survey on Working Conditions of Women Workers about a Part of Manufacture)

  • 이윤정;이정화;유찬영;박동기;유기호
    • 한국직업건강간호학회지
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    • 제12권1호
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    • pp.5-18
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    • 2003
  • The purpose of this study was to survey working conditions of women workers. We conducted a field survey of 504 manufacturing company with many women working from May 13 to June 29, 2002. We focused on only 3 categories of metal, textile and electronics industry. The result were as follows : 1. Subjects were constituted metal 27.0%, textile 37.9% and electronics industry 35.1%. Size distribution was small scale(<50 workers) 38.1%, medium(50-299 workers) 50.2% and large(${\geq}300$ workers) company 11.7%. Women workers' proportion was 43.6% of total workers, 63.8% of total contractors. 2. A medical examination enforcement of contractors workers was very poor in comparison with that of employees(p<0.001). 3. A 53.8% of total companies have conducted shiftwork system and 2-crew 2-shift(12 hours shift system) ranked first, 56.1%(151 companies). 4. Only 61.3% of total companies conducted more than 90 days as legal standard of a maternity leave and only 2.6% of total companies had a day nursery. In conclusion, many strategies for women workers are needed by companies and government. For example, the raising of understanding about maternity protection, social support insurancing of woman worker and occupational health system improvement for contractors and small size companies.

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The Movement of Boron Compound by Infusion Method and Combination of Injection and Bandage-Wrapping

  • DAMAYANTI, Ratih;SRIBUDIANI, Evi;SOMADONA, Sonia;Djarwanto, Djarwanto;TARMADI, Didi;AMIN, Yusup;YUSUF, Sulaeman;SATITI, Esti Rini;ARSYAD, Wa Ode Muliastuty;SULAEMAN, Rudianda;Syafrinal, Syafrinal;PRAMASARI, Dwi Ajias
    • Journal of the Korean Wood Science and Technology
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    • 제48권4호
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    • pp.513-526
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    • 2020
  • The existing preservation methods are difficult to be applied to a large dimension log which is needed for making traditional wooden ship 'Jalur' in Riau Province. Novel techniques to provide the use of readily available species to replace traditional species alternative were investigated. These included infusion and a combination of injection and bandage-wrapping methods for preserving living trees of Balam (Macaranga conifera (Rchb.f. & Zoll.) Müll.Arg.) and Bintangor (Calophyllum soulattri Burm.f.). Water-based boron compounds were applied as wood preservatives. In total, 18 discs from the bottom, middle, and top of four trees and two controls were used. Trees undergoing treatment were also used to see how wood anatomical structure might affect the boron penetration. The overall aim was to identify the best method for use in Jalur manufacturing. The results showed that in infused Balam tree where the hose position for the preservative intake was deep (10-15 cm from the bark), no boron compound was observed in the outer sapwood. Combination of injection and bandage-wrapping method gave higher percentage of boron penetration at bottom and middle of Balam tree. However, infused Bintangor showed 100% boron penetration. The larger vessel diameter, the absence of tyloses, and the simple perforation plates in Bintangor wood were likely to have contributed to the higher penetration of boron. The combination of bandage-wrapping and infusion, or alternatively by infusing the living trees close to the bark, and at as low as position in the stem gives better protection when treatments are applied to living trees.

빅데이터 개인정보보호 가이드라인(안)의 개선 방향에 관한 연구 (A Study on the Improvements of the Big Data Guideline in Korea)

  • 김선남;이환수
    • 정보화정책
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    • 제21권4호
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    • pp.20-39
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    • 2014
  • 빅데이터 시대의 도래는 산업 발전에 대한 긍정적 시각과 함께 개인정보보호 및 프라이버시 침해와 관련한 우려 또한 낳고 있다. 이러한 상황에서 최근 방송통신위원회는 빅데이터 환경에서 개인정보 수집과 이용 범위를 규정하는 '빅데이터 가이드라인(안)'을 제시하였다. 그러나 동 '가이드라인(안)'은 산업 진흥에 목적을 두고 있어, 기존 "개인정보보호법"과 충돌하는 내용을 많이 포함하고 있는 상황이다. 이에 시민단체들은 정보주체의 인권이나 프라이버시를 침해할 수 있다는 이유로 제정을 강력히 반대하며, 결국 개인정보위원회는 최근 전면 재검토를 요청했다. 따라서 본 논문에서는 현 '가이드라인(안)'의 한계점을 분석하고, 국내 외 관련 법률을 검토하여, 개인정보보호를 통한 프라이버시 침해를 최소화하는 방향에서 기업들이 빅데이터를 안전하게 활용할 수 있도록 법과 제도적 정비 방안에 대해 논의한다.