검색결과

검색조건
좁혀보기
검색필터
결과 내 재검색

간행물

    분야

      발행연도

      -

        검색결과 7

        1.
        2023.11 구독 인증기관·개인회원 무료
        Economical radioactive soil treatment technology is essential to safely and efficiently treat of high-concentration radioactive areas and contaminated sites during operation of nuclear power plants at home and abroad. This study is to determine the performance of BERAD (Beautiful Environmental construction’s RAdioactive soil Decontamination system) before applying magnetic nanoparticles and adsorbents developed by the KAERI (Korea Atomic Energy Research Institute) which will be used in the national funded project to a large-capacity radioactive soil decontamination system. BERAD uses Soil Washing Process by US EPA (402-R-007-004 (2007)) and can decontaminate 0.5 tons of radioactive soil per hour through water washing and/or chemical washing with particle size separation. When contaminated soil is input to BERAD, the soil is selected and washed, and after going through a rinse stage and particle size separation stage, it discharges decontaminated soil separated by sludge of less than 0.075 mm. In this experiment, the concentrations of four general isotopes (A, B, C, and D which are important radioisotopes when soil is contaminated by them.) were analyzed by using ICP-MS to compare before and after decontamination by BERAD. Since BERAD is the commercial-scale pilot system that decontaminates relatively large amount of soil, so it is difficult to test using radioactive isotopes. So important general elements such as A, B, C, and D in soil were analyzed. In the study, BERAD decontaminated soil by using water washing. And the particle size of soil was divided into a total of six particle size sections with five sieves: 4 mm, 2 mm, 0.850 mm, 0.212 mm, and 0.075 mm. Concentrations of A, B, C, and D in the soil particles larger than 4 mm are almost the lowest regardless of before and after decontamination by BERAD. For soil particles less than 4 mm, the concentrations of C and D decreased constantly after BERAD decontamination. On the other hand, the decontamination efficiency of A and B decreased as the soil particle became smaller, but the concentrations of A and B increased for the soil particle below 0.075 mm. As a result, decontamination efficiency of one cycle using BERAD for all nuclides in soil particles between 4 mm and 0.075 mm is about 45% to 65 %.
        2.
        2020.06 KCI 등재 구독 인증기관 무료, 개인회원 유료
        PURPOSES : Over the years, the concentration of fine dust is gradually increasing, thereby aggravating the seriousness of the situation. Accordingly, this study intends to install a clean road system using low impact development (LID) techniques on the roadside in order to reduce the scattering of dust on roads effectively. This system stores rainwater collected through gutters in rainy weather and sprays water onto the pavement surface to reduce the scattering of road dust. METHODS : The developed clean road system consists of a water tank, controller, rain detection sensor, and solar cell. Based on this, a test-bed construction was used to evaluate its applicability. By applying the developed system, actual applicability was evaluated through total suspended solid (TSS) test and fine dust measurement. TSS test was conducted to measure the reduction rate of scattering dust on the road owing to the water injected by the clean road system. A spray nozzle was used for the TSS test, and a nebulization nozzle was used for the measurement of fine dust. In order to increase the reliability of the test, three measurements were taken each, for normal road as well as unfavorable conditions road that reproduced the construction site. RESULTS : In this study, fine dust concentration measurement and TSS test were conducted to evaluate the practical applicability of the developed clean road system. From the TSS test, it was found that for both general roads and roads depicting bad conditions, the TSS value after the first spray was the highest, and the value after the second spray was sharply reduced, such that most of the re-dispersed dust was washed out after the first spray, and similar TSS value results were obtained after the third spray. Based on this result, the result of fine dust measurement showed similar fine dust reduction effect of 9%-15.9% regardless of the concentration of fine dust in the atmosphere. These results indicate that the concentration of fine dust in the atmosphere does not significantly affect of the degree of reduction in fine dust. CONCLUSIONS : In this study, a clean road system for reducing fine dust on the road was developed and its applicability was evaluated. In a future study, we intend to check the performance of the drainage pavement through performance evaluation of water permeability coefficient test and performance test in the form of drainage pavement. Through this, we intend to evaluate the applicability of the clean road system to which drainage pavement is applied. Moreover, we will develop a clean road system that applies drainage packaging, and analyzes the degree of fine dust reduction according to the spray angle, spray amount, and spray time of the clean road system in order to study the spray system with the optimum amount of fine dust reduction. In addition, in order to reduce fine dust in the winter, when fine dust is mainly generated, it is planned to install heating wires in spray pipes where freezing is expected. Lastly, the black ice prevention effect will be analyzed by mixing a certain amount of sodium chloride when spraying water.
        4,000원
        4.
        2014.06 KCI 등재 구독 인증기관 무료, 개인회원 유료
        With the radical changes and advancements of industrial economy, it is required to secure product competitiveness through technological innovations to overcome uncertain environments and generate a driving force for sustainable growth. So the Korea government introduced the superior product selection system in 1996 and has granted such incentives as priority purchasing and contracts the products of SME whose technological capabilities have passed the screening criteria. After analyzing the ambiguity of the evaluation procurement used in designation of excellent product, this study proposed seven detailed indexes for evaluation.
        4,000원
        5.
        2014.06 구독 인증기관 무료, 개인회원 유료
        시스템다이내믹스는 사회과학, 자연과학을 통틀어 다양한 현상을 체계화 시키고 동태적인 인과관계의 과학성을 분석하는데 있어 유용한 분석 방법론이다. 단기적 혹은 장기적인 사회성장에 관한 전략을 제시하거나 사고를 미연에 방지하기 위해 사례를 모아 원인을 분석하고 종합적인 고려를 통해 사고가 재 발생되지 않게 하는 정책을 제시할 수 있게 한다.
        3,000원
        6.
        2003.10 구독 인증기관 무료, 개인회원 유료
        Evaluating projects is one of the key activities in managing projects, and thus it should be implemented as a part of the entire project management system. However, currently deployed evaluation systems suffer from several deficiencies such as the lack of supporting distributed environment and integrity. In this paper, the web service technology is applied to evaluation management systems. The process of evaluation is designed based on the web service, and a pilot system is implemented to test the feasibility of the technology to the domain of project evaluation.
        3,000원
        7.
        2007.10 KCI 등재 서비스 종료(열람 제한)
        본 연구에서는 과학기술부의 21C 프론티어 사업 중 하나인 수자원의 지속적 확보기술개발사업단에서 연구 개발 중인 수자원 확보기술을 대상으로 기술평가 모형을 구축하였다. 이는 개발기술의 가치평가를 통하여 R&D가 효율적으로 사용되고 개발된 기술이 실용화 단계까지 성공적으로 갈 수 있도록 기여함에 있다. 수자원 확보기술의 성격을 반영할 수 있도록 정량적 평가뿐만 아니라 정성적 평가가 모두 가능한 2개의 계층으로 이루어진 평가틀이 구축되었다. 4개의 평가기준