• 제목/요약/키워드: Korean Environment

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하상재료에 따른 ADCP의 유량측정 비교 분석 (Comparative Analysis of ADCP Flow Measurement According to River Bed Material)

  • 최진우;홍창수;신경용;이진욱;김정애;조용철;유순주
    • Ecology and Resilient Infrastructure
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    • 제5권3호
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    • pp.156-162
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    • 2018
  • 본 연구는 하상재료에 따른 ADCP의 측정 적합성을 평가하기 위해 하상 재료가 다른 자갈 하상과 모래 하상인 지점에서 ADCP의 유속, 수심 및 유량 자료를 ADV의 측정 결과와 비교 분석하였다. 연구결과 자갈 하상과 모래 하상에서의 ADV와 ADCP를 이용한 유속 분포와 수심 측정 자료는 비슷하게 나타났다. 유량측정 결과 자갈 하상에서 평균 3.5 - 4.8%, 모래 하상에서 평균 0.02 - 3.2%의 상대오차 범위를 나타내어 USGS에서 제시한 평균 오차 5%의 범위보다 작아 신뢰가 높은 결과인 것을 알 수 있었다. 이한 결과는 향후 ADCP의 하천 적용성에 대한 기초자료로 활용될 수 있으며 ADCP의 불확도 평가에 중요한 자료로 이용될 것으로 판단된다.

Characteristics of long-range transported PM2.5 at a coastal city using the single particle aerosol mass spectrometry

  • Cai, Qiuliang;Tong, Lei;Zhang, Jingjing;Zheng, Jie;He, Mengmeng;Lin, Jiamei;Chen, Xiaoqiu;Xiao, Hang
    • Environmental Engineering Research
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    • 제24권4호
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    • pp.690-698
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    • 2019
  • Air pollution has attracted ever-increasing attention because of its substantial influence on air quality and human health. To better understand the characteristics of long-range transported pollution, the single particle chemical composition and size were investigated by the single particle aerosol mass spectrometry in Fuzhou, China from 17th to 22nd January, 2016. The results showed that the haze was mainly caused by the transport of cold air mass under higher wind speed (10 m·s-1) from the Yangtze River Delta region to Fuzhou. The number concentration elevated from 1,000 to 4,500 #·h-1, and the composition of mobile source and secondary aerosol increased from 24.3% to 30.9% and from 16.0% to 22.5%, respectively. Then, the haze was eliminated by the clean air mass from the sea as indicated by a sharp decrease of particle number concentration from 4,500 to 1,000 #·h-1. The composition of secondary aerosol and mobile sources decreased from 29.3% to 23.5% and from 30.9% to 23.1%, respectively. The particles with the size ranging from 0.5 to 1.5 ㎛ were mainly in the accumulation mode. The stationary source, mobile source, and secondary aerosol contributed to over 70% of the potential sources. These results will help to understand the physical and chemical characteristics of long- range transported pollutants.

비 무기산 세척제에 의한 중금속 오염 토양 세척효과 평가 (Evaluation on Soil Washing of Metal-contaminated Soil using Non-Inorganic Acids)

  • 이가빈;정원균;이수민;박진;조용환;백기태
    • 한국지하수토양환경학회지:지하수토양환경
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    • 제27권5호
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    • pp.10-17
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    • 2022
  • Inorganic acids such as HCl, HNO3, and H2SO4 have been commonly applied to soil washing of heavy metals-contaminated soil due to their cost-effectiveness. However, implementing the 'Chemical Substance Control Act' requires off-site risk assessment of the chemicals used in the soil washing. Therefore, in this study, organic acids or Fe(III)-based washing agents were evaluated to replace commonly used inorganic acids. Ferric removed heavy metals via H+ generated by hydrolysis, which is similar to the HCl used in the control group. Oxalic acid and citric acid were effective to remove Cu, Zn, and Cd from soil. Organic acids could not remove Pb because they could form Pb-organic acid complexes with low solubility. Furthermore, Pb could be adsorbed onto the iron-organic acid complex on the soil surface. Ferric could remove exchangeable-carbonate, Fe-Mn hydroxide, and organic matter and sulfides bound heavy metals (F1, F2, and F3). Organic acids could remove the exchangeable-carbonate and Fe-Mn hydroxide bound metals (F1&F2). Therefore, this research shows that the fractionation of heavy metals in the soil and the properties of washing agents should be considered in the selection of agents in the process design.

중학교 "환경" 교과서의 내용조직 체계와 교수-학습 방법과의 연계성 (A Study on the Relation between the Content Organization System of Environment Textbooks for the Middle School and the Teaching & Learning Methods of the 7th Korean National Curriculum)

  • 구수정;진은화;유은습;심선보
    • 한국환경교육학회지:환경교육
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    • 제14권2호
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    • pp.15-27
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    • 2001
  • The purpose of this study is to understand and compare the characteristics of the content organization system of three Environment textbooks currently used, and to examine its connectivity with the teaching & teaming methods included in the Environment subject part of the 7th Korean National Curriculum. For the analysis three Environment textbooks for middle school and their teacher's guide books by three companies. published(A, B, and C) The result of the taxonomic analysis showed that three Environment books had different steps to get to the lesson class unit in the way that A of six steps, B of five steps and C of seven steps. The amount of main text was different In the domains of'Human and Environment','Environmental Problems and its Counter-plan'and'Environmental Conservation'of three textbooks each. All of three textbooks had the biggest percentage in sub-domains of'Living Environment to Keep'and'Global Environmental Problem'in 'Environmental Problems and its Counter-plan'domain. Considering teaching & loaming methods all of three textbooks contained many activities as 55 in A, 66 in H and 91 in C. Among 9 teaching 8E teaming methods and others listed in the Environment subject part of the 7th Korean National Curriculum, the investigation method is most frequently used in all of three textbooks. The drama, the paly and the case study were used rarely as teaching & teaming methods in activities In the consideration of the content amount regarding academic fields, it was revealed that three textbooks overemphasized the aspect of natural sciences comparing the aspect of human & social sciences aspect as a whole. Generally the appendix section of all three textbooks were well organized to support the teaching and teaming activities in main text.

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데이터 웨어하우스 기술을 활용한 학교시설물의 환경개선예산 분석 - OO교육청 초·중·고등학교를 중심으로 - (Analysis of Environment Improving Budget of School Facilities by Using Data Warehouse Technology - Focused on Elementary, Middle, High School of OO Office of Education -)

  • 박민규;손창백;류한국
    • 교육녹색환경연구
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    • 제13권1호
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    • pp.15-23
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    • 2014
  • With introduction of amended educational curriculum in 2007, optimizing project of educational environment to accomplish its purposes and goals includes expanding educational facilities and supplying eco-friendly school facilities. However, while the focus of optimizing project of educational environment is quality improvement of educational facilities, aging of these facilities built at th times of quantitative expansion and its management become serious problems. Higher concerns on studies and jobs on management of building caused by serious aging of facilities, management cost of building becomes a very crucial issue. Therefore, this study aims to analyze environment improvement budget of school facilities through building and using data warehouse, by investigating and analyzing the current status of environment improvement budget of school facilities and its cost through questionnaire and interview surveys on officers who are in charge of environment improvement budget of school facilities in educational administrations. This study thus analyzed environment improving budget of school facilities by using data warehouse technology collecting related data to the topic and setting levels by region, school class, establishment year, school facility types and others.

중학생이 지각한 심리적 성장환경의 자율성과 분노행동의 관계에서 비합리적 신념의 매개효과 (Mediating Effects of Irrational Beliefs on the Relationships Between Autonomy of Psychological Growth Environment and Behavioral Anger Responses Perceived by Middle School Students)

  • 김태은
    • 가정과삶의질연구
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    • 제34권6호
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    • pp.27-40
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    • 2016
  • This study examined the mediating effects of irrational beliefs on the relationships of middle school students' autonomy of psychological growth environment and behavioral anger responses(impulsive reaction, verbal aggression, physical confrontation and indirect expression). A sample of 346 first and second year students of middle school participated in the autonomy of psychological growth environment scale, the irrational beliefs scale and behavioral anger responses scale. Pearson's correlation analysis and regression analysis were performed. The results showed that: ⑴ The relations among autonomy of psychological growth environment, irrational beliefs and behavioral anger responses were significant. The autonomy of psychological growth environment had negative correlations with irrational beliefs and behavioral anger responses. Irrational beliefs produced positive correlations with behavioral anger responses. There were positive correlations among the subtypes of behavioral anger responses. ⑵ There were mediating effects of irrational beliefs between autonomy of psychological growth environment and behavioral anger responses. The effects of autonomy of psychological growth environment on impulsive reaction, physical confrontation and indirect expression were fully mediated by irrational beliefs. However, the effect of autonomy of psychological growth environment on verbal aggression was partially mediated by irrational beliefs. This study demonstrated that irrational beliefs mediate the relationship between autonomy of psychological growth environment and behavioral anger responses.