• 제목/요약/키워드: Long-term safety assessment

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노인환자의 특성을 고려한 노인요양병원 치유환경 평가지표 (A Study on the Development of the Healing Environment Evaluation Criteria for Elderly Care Hospital focusing on the Elderly Inpatient Characteristics)

  • 전수경;남경숙
    • 한국실내디자인학회논문집
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    • 제26권4호
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    • pp.22-29
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    • 2017
  • This paper investigates the evaluation criteria in order to manage healing environment of long-term care elderly hospital. Elderly hospital evaluation tool developed by Korean Government is used to assess elderly hospital facilities to check the hospital facility and maintain its quality. However, the evaluation indicators and questions mainly focusing on safety indicators. Some questions are too vague for precise evaluation. In this paper, we discuss the advantages and disadvantages of the present evaluation criteria to establish new assessment tool for precise evaluation. The literature research was conducted tp set up the new evaluation criteria. From this research, we developed an elderly focusing on healing environment checklist for elderly care hospital which contains 7 factors as the primary hierarchy structure (Safety, Accessibility, Amenity, Sensibility, Friendly to nature, Territory, Interaction) and 23 factors as the secondary hierarchy structure. This evaluation criteria will help healthcare facility designers and healthcare organizations to build the healthcare facilities.

ENHANCEMENT OF DRYOUT HEAT FLUX IN A DEBRIS BED BY FORCED COOLANT FLOW FROM BELOW

  • Bang, Kwang-Hyun;Kim, Jong-Myung
    • Nuclear Engineering and Technology
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    • 제42권3호
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    • pp.297-304
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    • 2010
  • In the design of advanced light water reactors (ALWRs) and in the safety assessment of currently operating nuclear power plants, it is necessary to evaluate the possibility of experiencing a degraded core accident and to develop innovative safety technologies in order to assure long-term debris cooling. The objective of this experimental study is to investigate the enhancement factors of dryout heat flux in debris beds by coolant injection from below. The experimental facility consists mainly of an induction heater, a double-wall quartz-tube test section containing a steel-particle bed and coolant injection and recovery condensing loop. A fairly uniform heating of the particle bed was achieved in the radial direction and the axial variation was within 20%. This paper reports the experimental data for 3.2 mm and 4.8 mm particle beds with a 300 mm bed height. The dryout heat density data were obtained for both the top-flooding and the forced coolant injection from below with an injection mass flux of up to $1.5\;kg/m^2s$. The dryout heat density increased as the rate of coolant injection increased. At a coolant injection mass flux of $1.0\;kg/m^2s$, the dryout heat density was ${\sim}6.5\;MW/m^3$ for the 4.8 mm particle bed and ${\sim}5.6\;MW/m^3$ for the 3.2 mm particle bed. The enhancement factors of the dryout heat density were 1.6-1.8.

PYROPROCESS WASTE DISPOSAL SYSTEM DESIGN AND DOSE CALCULATION

  • Kook, Dong-Hak;Cho, Dong-Keun;Lee, Min-Soo;Lee, Jong-Youl;Choi, Heui-Joo;Kim, Yong-Soo
    • Nuclear Engineering and Technology
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    • 제44권5호
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    • pp.483-490
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    • 2012
  • PWR spent fuels produced in the Republic of Korea are expected to be recycled by pyroprocess in the long term future. Even though pyroprocess waste amounts can be smaller than that of PWR spent fuel assembly in case of direct disposal, this process essentially will produce various and unique radioactive wastes. The goals of this article are to characterize these wastes, calculate the amount of wastes, design disposal systems for each waste and evaluate the radiation safety of each system by dose assessment. The absorbed dose results of the metal and ceramic waste for the engineering barrier system (EBS) showed $2.21{\times}10^{-2}$ Gy/h and $1.15{\times}10^{-2}$ Gy/h, which are lower than the recommended value of 1 Gy/h. These results confirmed that the newly proposed disposal systems have a safety margin for the radiation produced from each waste.

DEVELOPMENT OF GREEN'S FUNCTION APPROACH CONSIDERING TEMPERATURE-DEPENDENT MATERIAL PROPERTIES AND ITS APPLICATION

  • Ko, Han-Ok;Jhung, Myung Jo;Choi, Jae-Boong
    • Nuclear Engineering and Technology
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    • 제46권1호
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    • pp.101-108
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    • 2014
  • About 40% of reactors in the world are being operated beyond design life or are approaching the end of their life cycle. During long-term operation, various degradation mechanisms occur. Fatigue caused by alternating operational stresses in terms of temperature or pressure change is an important damage mechanism in continued operation of nuclear power plants. To monitor the fatigue damage of components, Fatigue Monitoring System (FMS) has been installed. Most FMSs have used Green's Function Approach (GFA) to calculate the thermal stresses rapidly. However, if temperature-dependent material properties are used in a detailed FEM, there is a maximum peak stress discrepancy between a conventional GFA and a detailed FEM because constant material properties are used in a conventional method. Therefore, if a conventional method is used in the fatigue evaluation, thermal stresses for various operating cycles may be calculated incorrectly and it may lead to an unreliable estimation. So, in this paper, the modified GFA which can consider temperature-dependent material properties is proposed by using an artificial neural network and weight factor. To verify the proposed method, thermal stresses by the new method are compared with those by FEM. Finally, pros and cons of the new method as well as technical findings from the assessment are discussed.

Management Strategies for Heavy Metals to Secure the Crop Safety in Korea

  • Yang, J.E.;Kim, W.I.;Ok, Y.S.;Lee, J.S.
    • 한국환경농학회:학술대회논문집
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    • 한국환경농학회 2009년도 정기총회 및 국제심포지엄
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    • pp.93-115
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    • 2009
  • There are growing public concerns over crop and food safeties due to the elevated levels of heavy metals grown in contaminated soil. Heavy metals are classified as the chemical harmful risks for crop and food safety. With implementation of GAP, crop safety is controlled by many regulatory options for soil, irrigation water and fertilizers. Any attempt to retard the metal uptake by crops may be the best protocol to secure crop and food safety. This article reviews the management strategies for heavy metals in view of crop safety in Korea and demonstrates results from the field experiments to retard metal translocation from soil to crops by using chemical amendments and soil layer management methods. Major source of soil pollution by heavy metals has been related with mining activities. Risk assessment revealed that rice consumption and groundwater ingestion in the abandoned mining areas were the major exposure pathways for metals to human and the heavy metal showed the toxic effects on human health. Chemical amendments such as lime and slag retarded Cd uptake by rice (Oryza sativa L.) by increasing soil pH, lowering the phytoavailable Cd concentration in soil solution, immobilizing Cd in soil and converting the available Cd fractions into non-available fractions. The soil layer management methods decreased the Cd uptake by 76% and Pb by 60%. Either reversing the surface layer with subsurface layer or immobilization of metals with layer mixing with lime was considered to be the practical option for the in-situ remediation of the contaminated paddy soils. Combination of chemical soil amendments and layer management methods was efficient to retard the metal bioavailability and thus to secure crop safety for heavy metals. This protocol seems to be cheap, relatively easy to practice and practical in the agricultural fields. However, a long term monitoring work should be followed to verify the efficiency of this protocol.

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지오그리드의 시공 시 손상 및 크리프 변형의 복합효과 평가 (Assessment of Combined Effect of Installation Damage and Creep Deformation of Geogrids)

  • 조삼덕;이광우;오세용;이도희
    • 한국지반공학회논문집
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    • 제21권5호
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    • pp.153-161
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    • 2005
  • 시공 시 손상 및 크리프 변형의 복합효과가 지오그리드의 장기설계인장강도에 미치는 영향을 평가하기 위하여, 세 종류의 지오그리드를 대상으로 일련의 현장 내시공성시험 및 크리프시험을 수행하였다. 연구결과, 지오그리드의 시공시 손상 및 크리프 변형 특성은 지오그리드의 재질 및 제조방법에 크게 영향을 받으며, 시공 중 지오그리드의 인장강도감소가 클수록, 시공 시 손상과 크리프 변형의 복합효과가 미치는 영향이 더 큰 것으로 나타났다. 또한 지오그리드의 인장강도 감소계수를 영향인자별로 각각 산정하여 장기설계인장강도를 평가하도록 되어 있는 현행 설계법은, 지오그리드의 시공 시 손상과 크리프 변형의 복합효과를 고려하여 강도감소계수를 산정하는 방법에 비해 지오그리드의 강도감소계수를 안전측으로 산정하는 것으로 평가되었다.

산업단지 「인·허가 특례법」 이후 개발계획에 따른 국내 대기질 영향예측 (Air Quality Assessment for Development Plan after the Special Act on Licensing of Industrial Complexes)

  • 문난경;김순태;서지현
    • 한국환경과학회지
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    • 제26권11호
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    • pp.1209-1222
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    • 2017
  • On June 5, 2008, the "Act on Special Cases Concerning the Simplification of Authorization and Permission Procedures for Industrial Complexes" (Act No. 9106) was enacted. When it was implemented in August 2008, many industrial complex development projects were established, and the number of industrial complexes growth rates of 3-6% during 2003-2007 rose to around 15% in 2008. With the increase in industrial complexes, the environmental impacts of individual projects were examined, but comprehensive regional reviews of environmental impacts were not undertaken. In this study, we determined changes in air quality by applying the industrial complex development plan that completed the consultation at the end of 2010 to assess the comprehensive regional environmental impacts and presented the adequacy review plan for future industrial development plans based on the study's results. When considering these industrial complex development plans, emissions in North Jeolla and South Chungcheong Provinces and Daegu City have increased significantly. Air quality analyses showed that the 24 h mean $SO_2$ concentration in Daegu increased by more than 50% in summer compared to air quality concentrations in summer. The 24 h mean $PM_{10}$ and $NO_2$ concentrations increased by approximately 12 and 30%, respectively, in North Jeolla Province in summer. Areas exceeding the air quality standard for 1 h mean $O_3$ concentration increased by more than $3,500km^2$. Based on the above analysis, changes in air quality should be anticipated through a comprehensive evaluation of long-term development plans. Furthermore, control of air quality in accordance with the development of future industrial complexes is possible.

고준위 방사성폐기물 처분장에서 초기 용기 파손 시나리오의 장기 방사선적 안전성 평가 (Post Closure Long Term Safety of an Initial Container Failure Scenario for a Potential HLW Repository)

  • 황용수;서은진;이연명;강철형
    • 한국방사성폐기물학회:학술대회논문집
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    • 한국방사성폐기물학회 2003년도 가을 학술논문집
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    • pp.229-232
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    • 2003
  • 고준위 방사성폐기물 처분장에서 적용하고 있는 다중 방벽의 한 부분인 처분 용기는 벤토나이트 완충재의 팽윤과 지압으로부터 폐기물을 역학적으로 안전하게 보호함과 동시에 일정 기간 방사성폐기물의 유출을 억제하는 역할을 한다. 용기는 엄격한 재질 선정과 품질 보증을 거쳐 건전성을 확보하나 보수적인 관점에서 보면 용기 제작 과정이나 수송 중 예상치 못한 사건으로 인해 불량품이 발생할 개연성이 있다. 본 연구에서는 이와 같은 사고 시나리오를 가정할 경우 불량 용기를 포함한 전체 용기에 거치된 방사성폐기물의 시간에 따른 환경 위해도를 평가하였다. 본 연구결과 일부 처분 용기에 초기 파손이 발생하더라도 규제치를 잘 만족하는 것으로 판명되었다.

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A New Complex Minimally Invasive Thread Lift Method for One-Time Three-Step Fixation of the Face and Neck Soft Tissues

  • Zhukova, Olga;Dydykin, Sergey;Kubikova, Eliska;Markova, Natalia;Vasil'ev, Yuriy;Kapitonova, Marina
    • Archives of Plastic Surgery
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    • 제49권3호
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    • pp.296-303
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    • 2022
  • Background In recent years thread lift has become widespread; however, existing methods need to improve their long-term outcome, which requires considering topographic anatomy of face and neck, especially the ligamentous apparatus. This study aims to assess the effectiveness and safety of an innovative method of one-time three-step thread facelift, which provides an additional support to the ligamentous structures of the upper, middle, and lower thirds of the face and neck. Methods The study included 357 patients aged 32 to 67 years with various morphotypes of aging. The original method of thread lift was applied, and its effectiveness was followed up for to 2 years. The Wrinkle Severity Rating Score (WSRS) and Global Aesthetic Improvement Scale (GAIS) scores were used for assessment by investigators, independent observers, and patients. Statistical significance was determined using paired t-test and chi-square test. Results The mean WSRS score was 3.88 ± 0.88 before the thread lift, 1.93 ± 0.81 one month after the procedure, and 2.36 ± 0.85 after 2 years of follow-up. The mean GAIS was 4.80 ± 0.04 one month after thread lift, and 4.01 ± 0.04 after 2 years, while in the patients' assessment Global Satisfaction Scale was 4.86 ± 0.02 and 4.10 ± 0.02, respectively. There were no clinically significant complications throughout the observation period. Conclusion The new method of one-time three-step thread fixation of the soft tissues of the face and neck demonstrated a high degree of satisfaction by both experts and patients after 2 years of follow-up. It showed high efficacy and safety, including in the group of patients with pronounced age-related changes of the skin of face and neck.

Assessment of environmental impact of vitamin A-enhanced soybeans and hybrid soybeans

  • Sung-Dug Oh;Ji Eun Choi;Ye-Jin Jang;Seong-Kon Lee;Gang-Seob Lee;Ancheol Chang;Doh-Won Yun
    • 농업과학연구
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    • 제50권4호
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    • pp.749-758
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    • 2023
  • An understanding of safety problems pursuant to environmental release of GM (Genetically Modified) crops is considered important. Among the recognized safety problems, the possibilities of weediness and ecosystem invasion are constantly being validated. We herein compared the growth characteristics and germination rate of soybeans formed by hybridization with vitamin A-enhanced soybeans carrying an introduced gene that increases β-carotene content. We also examined overwintering, survival, and weed competitiveness to evaluate hybrid ecological impact on long-term unmanaged cultivatable land. These studies revealed that the hybrid soybeans exhibited intermediate growth characteristics and germination rate compared with the vitamin A-enhanced soybeans and wild soybeans, or exhibited traits similar to those of the maternal strain. Overwintering experiments were conducted by planting seeds at depths of 0, 5, 10, and 20 cm and recovering them after three or five months. After five months, all seeds at depths more than 5 cm lost viability. Among seeds recovered after three months, only wild soybeans retained viability at depths of more than 5 cm. Survival and weed competitiveness were assessed by sowing each type of seed and performing no irrigation, or pest or weed control. Quantitative assessment of numbers of individual soybean plants that appeared in the experimental plot revealed that all plants germinated after sowing, but only wild type plants survived overwintering. These studies suggest that both GM soybeans and hybrid soybeans cannot survive in uncultivated land even if they are released into the environment, which indicates less possibility of ecosystem invasion and weediness.