• Title/Summary/Keyword: Regulatory limits

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The Status Quo and Direction of Development of Environmental Impact Assessment System in Korea (우리나라 환경영향평가제도의 현주소와 발전방향에 관한 연구)

  • Choi, Joon-Gyu
    • Journal of Environmental Impact Assessment
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    • v.9 no.2
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    • pp.155-161
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    • 2000
  • Environmental impact assessment(EIA), the only preventive system to manage development projects destroying the nature and ecosystem systematically, has been accomplished since the late 1970. EIA connotes intrinsic limits predicting uncertain future with the aid of present data. Furthermore, EIA has been used as not decision-making tools but regulatory means. Therefore, EIA has been criticized severely. In order to present direction of development of EIA, we analyzed problems of management of EIA, and concluded measures as follows are needed. 1. Control of investigation of environmental impact statements 2. Development of evaluating methods and publication 3. Fostering of institute for research and investigation of EIA 4. Construction of harmony of environment and development 5. Upgrade of state of proxy executing EIA.

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Geotechnical Properties and Environmental Effect of Waste Gymsum (폐석고의 공학적 특성 및 환경적 영향 분석에 관한 연구)

  • 신은철;오영인;이희재
    • Proceedings of the Korean Society of Soil and Groundwater Environment Conference
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    • 1999.10a
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    • pp.90-94
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    • 1999
  • Waste gypsum is produced about 2.6million tons per year as a by-product in the process of TiO$_2$production. Geotechnical properties such as natural water content, specific gravity, Atterberg limits were determined to figure out the engineering characteristics waste gypsum. Grain-size distribution, compaction, CBR tests, and unconfined compression test for various mixing ratios between waste gypsum and decomposed granite soil 8t dredged soil. The environmentally adverse effect for mixed specimen with waste gypsum is far below than those of regulatory requirement.

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RADIATION SHIELDING EVALUATION OF IP-2 PACKAGES FOR LOW- AND INTERMEDIATE-LEVEL RADIOACTIVE WASTE

  • Kim, Min-Chul;Choi, Jong-Rak;Chung, Sung-Hwan;Ko, Jae-Hoon
    • Nuclear Engineering and Technology
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    • v.40 no.6
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    • pp.511-516
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    • 2008
  • Korea Hydro & Nuclear Power Co., Ltd. (KHNP) developed new IP-2 packages to transport low- and intermediate-level radioactive waste (LILW) steel drums from nuclear power plants to a disposal facility in accordance with IAEA and Korean transport regulations of radioactive material. Radiation shielding evaluation of the packages was carried out to demonstrate compliance with the regulatory requirements for IP-2 packages of radioactive material. Dose rate limits of LILW drums contained in the packages were determined.

RECENT UPDATES TO NRC FUEL PERFORMANCE CODES AND PLANS FOR FUTURE IMPROVEMENTS

  • Geelhood, Kenneth
    • Nuclear Engineering and Technology
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    • v.43 no.6
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    • pp.509-522
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    • 2011
  • FRAPCON-3.4a and FRAPTRAN 1.4 are the most recent versions of the U.S. Nuclear Regulatory Commission (NRC) steady-state and transient fuel performance codes, respectively. These codes have been assessed against separate effects data and integral assessment data and have been determined to provide a best estimate calculation of fuel performance. Recent updates included in FRAPCON-3.4a include updated material properties models, models for new fuel and cladding types, cladding finite element analysis capability, and capability to perform uncertainty analyses and calculate upper tolerance limits for important outputs. Recent updates included in FRAPTRAN 1.4 include: material properties models that are consistent with FRAPCON-3.4a, cladding failure models that are applicable for loss-of coolant-accident and reactivity initiated accident modeling, and updated heat transfer models. This paper briefly describes these code updates and data assessments, highlighting the particularly important improvements and data assessments. This paper also discusses areas of improvements that will be addressed in upcoming code versions.

FRAPCON analysis of cladding performance during dry storage operations

  • Richmond, David J.;Geelhood, Kenneth J.
    • Nuclear Engineering and Technology
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    • v.50 no.2
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    • pp.306-312
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    • 2018
  • There is an increasing need in the United States and around the world to move used nuclear fuel from wet storage in fuel pools to dry storage in casks stored at independent spent fuel storage installations or interim storage sites. Under normal conditions, the Nuclear Regulatory Commission limits cladding temperature to $400^{\circ}C$ for high-burnup (>45 GWd/mtU) fuel, with higher temperatures allowed for low-burnup fuel. An analysis was conducted with FRAPCON-4.0 on three modern fuel designs with three representative used nuclear fuel storage temperature profiles that peaked at $400^{\circ}C$. Results were representative of the majority of US light water reactor fuel. They conservatively showed that hoop stress remains below 90 MPa at the licensing temperature limit. Results also show that the limiting case for hoop stress may not be at the highest rod internal pressure in all cases but will be related to the axial temperature and oxidation profiles of the rods at the end of life and in storage.

Standardization Trends on Artificial Intelligence in Medicine (의료 인공지능 표준화 동향)

  • Jeon, J.H.;Lee, K.C.
    • Electronics and Telecommunications Trends
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    • v.34 no.5
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    • pp.113-126
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    • 2019
  • Based on the accumulation of medical big data, advances in medical artificial intelligence technology facilitate the timely treatment of disease through the reading the medical images and the increase of prediction speed and accuracy of diagnoses. In addition, these advances are expected to spark significant innovations in reducing medical costs and improving care quality. There are already approximately 40 FDA approved products in the US, and more than 10 products with K-FDA approval in Korea. Medical applications and services based on artificial intelligence are expected to spread rapidly in the future. Furthermore, the evolution of medical artificial intelligence technology is expanding the boundaries or limits of various related issues such as reference standards and specifications, ethical and clinical validation issues, and the harmonization of international regulatory systems.

A Leaching Characteristics on Lime Stabilization of Heavy Metal Contaminated Soil in a Waste Mine Area (폐 광산 지역 중금속 오염 토양의 석회안정화 적용 시 용출특성)

  • Oa, Seong-Wook
    • Journal of Korean Society on Water Environment
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    • v.27 no.6
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    • pp.862-867
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    • 2011
  • Pozzolanic-based stabilization/solidification (S/S) is an effective and economic remediation technology to immobilize heavy metals in contaminated soils. In this study, quick lime (CaO) was used to immobilize cadmium and zinc present in waste mine contaminated clayey sand soils. Addition of 5% quicklime to the contaminated soils effectively reduced heavy metal leachability after 2 bed volume operation below the drinking water regulatory limits. Lime addition was revealed to increase the immobilization for all heavy metals in tested pH ranges, so it could be an optimal choice for short-term remediation of heavy metal contaminated soil. The mass balances for these column tests show metal reduction of 92% for Cd and 87% for Zn of total resolved mass in case of 5% lime application.

Exploring Staphylococcus aureus Virulence Factors; Special Emphasis on Staphyloxanthin

  • Yehia, Fatma Al-zahraa A.;Yousef, Nehal;Askoura, Momen
    • Microbiology and Biotechnology Letters
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    • v.49 no.4
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    • pp.467-477
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    • 2021
  • Staphylococcus aureus is a well-known pathogen that can cause diseases in humans. It can cause both mild superficial skin infections and serious deep tissue infections, including pneumonia, osteomyelitis, and infective endocarditis. To establish host infection, S. aureus manages a complex regulatory network to control virulence factor production in both temporal and host locations. Among these virulence factors, staphyloxanthin, a carotenoid pigment, has been shown to play a leading role in S. aureus pathogenesis. In addition, staphyloxanthin provides integrity to the bacterial cell membrane and limits host oxidative defense mechanisms. The overwhelming rise of Staphylococcus resistance to routinely used antibiotics has necessitated the development of novel anti-virulence agents to overcome this resistance. This review presents an overview of the chief virulence determinants in S. aureus. More attention will be paid to staphyloxanthin, which could be a possible target for anti-virulence agents.

The Study on the Way of Radioactive Waste Disposal in China

  • Keyan Teng;Hao Peng;Caixia Lv;Han Wu
    • Journal of Nuclear Fuel Cycle and Waste Technology(JNFCWT)
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    • v.20 no.4
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    • pp.533-540
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    • 2022
  • Because of the massive development of nuclear power plants in China in recent years, China is facing the challenge of radioactive waste disposal. China has established complete regulatory requirements for radioactive waste disposal, but it also has encountered problems and challenges in low-level radioactive waste disposal in terms of management, selection of disposal facility sites, and implementation of a site selection plan. Three low-level radioactive waste disposal facilities that have been operated in China are described, and their activity limits, locations, and capacities are also outlined. The connotations of "regional" and "centralized" disposal policies are discussed in light of the characteristics of the radioactive waste. The characteristics and advantages of the regional and centralized disposal policies are compared. It is concluded that the regional disposal policy adopted in 1992 can no longer meet the current disposal needs, and China should adopt a combination of the two disposal policies to solve the problem of radioactive waste disposal.

The content and risk assessment of heavy metals in commercial herbal medicines (서울지역 유통한약재의 중금속 함량 및 위해성 평가)

  • Young Shin;Sang-Hun Park;Seung-Hye Han;So-Hyun Park;Ji-Hye Kim;Hyun-Jung Jang;Ae-Kyoung Kim;Ju-Seung Park
    • Analytical Science and Technology
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    • v.36 no.6
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    • pp.267-280
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    • 2023
  • This study investigated the contents of Pb, Cd, As, and Hg for 4333 samples with 2 09 types of herbal medicines distributed in Seoul area from 2019 to 2021, and evaluated risk assessment according to medicinal part used and origin. The contents of heavy metals were analyzed by inductively coupled plasma mass spectrometry (ICP-MS) and mercury analyzer. The average contents (mg/kg) of heavy metals by medicinal parts were 0.123 to 1.290 for Pb, 0.018 to 0.131 for Cd, 0.034 to 0.290 for As, and 0.003 to 0.015 for Hg. The contents of Pb were higher in Leaves and Whole Herbs (above-ground part) than underground part (Radix & Rhizoma) (ANOVA-test, p < 0.05). The contents of Cd were high in Leaves, Radix & Rhizoma, and Stems & Woods (ANOVA-test, p <0 .05), and exceeded regulatory limits in various types. Levels of Pb, Cd concentrations exceeding regulatory limits were observed in 8, 22 samples (8, 14 types). No sample exceeded regulatory limits of As and Hg. In the comparison between countries of origin, the contents of Cd, As, and Hg were high in imported herbal medicines (t-test, p < 0.05). As a result of the risk assessment, except for Thujae Orientalis Folium and Spirodelae Herba, the MOE values of Pb were all 1 or more, and most samples were safe. The Hazard Index (HI) for Cd, As, and Hg were evaluated to be less than 100 % even if the risk (%) of each heavy metal was added, and the risk from taking herbal medicines was evaluated to be safe.