• Title/Summary/Keyword: NRC

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FALCON code-based analysis of PWR fuel rod behaviour during RIA transients versus new U.S.NRC and current Swiss failure limits

  • Khvostov, G.;Gorzel, A.
    • Nuclear Engineering and Technology
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    • v.53 no.11
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    • pp.3741-3758
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    • 2021
  • Outcomes of the FALCON code analysis-related part of the STARS-ENSI Service Project on Evaluation of the new U.S.NRC RIA Fuel Safety Criteria and Application to the Swiss Reactors are presented. Substantial conservatism of the updated safety limits for high-temperature and PCMI cladding failure, as proposed in the NRC Regulatory Guide RG 1.236, is confirmed. Applicability of the updated failure limits to fuel safety analysis in the Swiss PWRs, as applied to standard fuel designs using UO2 fuel pellets and SRA Zry-4 as cladding materials is discussed. Conducting of new integral RIA tests with irradiated samples using doped- and gadolinia fuel pellets to support appropriate fuel safety criteria for RIA events is recommended.

Clinical Features of Retinal Correspondence according to Refractive Errors and Deviation Angles (굴절이상과 편위각에 따른 망막대응의 임상적 고찰)

  • Wi, Dae-Gwang;Joo, Seok-Hee;Lee, Koon-Ja;Leem, Hyun-Sung
    • Journal of Korean Ophthalmic Optics Society
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    • v.15 no.4
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    • pp.367-372
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    • 2010
  • Purpose: The purpose of this study was to provide useful information for evaluating the sensory function of patients with strabismus by identifying the distribution of anomalous retinal correspondence (ARC) and normal retinal correspondence (NRC) by the degree of refractive errors and deviation angles. Methods: Objective refraction (AR/K, Cannon RK-F1, Japan) and subjective refraction tests were performed on 56 subjects (male: 26, female: 30) by an examiner; objective deviation angle was measured using synoptophore (OCULUS Synoptophore, Germany) with subject' eyes fully corrected for distance, and then subjective deviation angle was measured. Results: In all groups with refractive errors, the number of ARC was larger than that of NRC(67%). Particularly, it was largest in groups with myopia (71%), and in all groups, the number of UARC was larger than that of HARC. In groups with anisometropia, although the numbers of NRC and ARC were same, the number of UARC was larger than that of HARC as in other groups. In the distribution of NRC and ARC by deviation angle, the number of NRC was larger than that of ARC (46%) only at microstrabismus (0 ~ ${\pm}10{\triangle}$). Conclusions: Normal retinal correspondence were the most emmetropia in the retinal response were much higher than in the more hyperopia than the retinal correspondence were more myopia. In addition, the smaller the angle of retinal correspondence Normal over many, but overall, respectively.

Influence of Modelling Approaches of Diffusion Coefficients on Atmospheric Dispersion Factors (확산계수의 모델링방법이 대기확산인자에 미치는 영향)

  • Hwang, Won Tae;Kim, Eun Han;Jeong, Hae Sun;Jeong, Hyo Joon;Han, Moon Hee
    • Journal of Radiation Protection and Research
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    • v.38 no.2
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    • pp.60-67
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    • 2013
  • A diffusion coefficient is an important parameter in the prediction of atmospheric dispersion using a Gaussian plume model, and its modelling approach varies. In this study, dispersion coefficients recommended by the U. S. Nuclear Regulatory Commission's (U. S. NRC's) regulatory guide and the Canadian Nuclear Safety Commission's (CNSC's) regulatory guide, and used in probabilistic accident consequence analysis codes MACCS and MACCS2 have been investigated. Based on the atmospheric dispersion model for a hypothetical accidental release recommended by the U. S. NRC, its influence to atmospheric dispersion factor was discussed. It was found that diffusion coefficients are basically predicted from a Pasquill- Gifford curve, but various curve fitting equations are recommended or used. A lateral dispersion coefficient is corrected with consideration for the additional spread due to plume meandering in all models, however its modelling approach showed a distinctive difference. Moreover, a vertical dispersion coefficient is corrected with consideration for the additional plume spread due to surface roughness in all models, except for the U. S. NRC's recommendation. For a specified surface roughness, the atmospheric dispersion factors showed differences up to approximately 4 times depending on the modelling approach of a dispersion coefficient. For the same model, the atmospheric dispersion factors showed differences by 2 to 3 times depending on surface roughness.

Nutrient Balance For The Laying Hen (산란계를 위한 영양소의 균형)

  • ;J. M. Vandepopuliere
    • Korean Journal of Poultry Science
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    • v.8 no.1
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    • pp.37-45
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    • 1981
  • 급격히 증가하는 세계의 인구수는 가축의 사료자원을 질이 좋은 인간 식량으로 효율적으로 전환할 필요성을 절실케 하고 있다. 산란계는 유전적인 선택에 의해 최소량의 사료로써 높은 산란율을 유지할 수 있도록 개선되어 왔다. 배합사료의 생산에 사용될 수 있는 단미사료의 종류와 품질은 어느 특정한 영양소의 요구량에 의하여 좌우된다. 산란계의 영양요구량은 오랜동안 연구되어 왔으며, 미국의 국립연구위원회 (NRC)는 영양소 요구량을 정기적으로 검토, 요약하고 있다. 새로운 정보들은 출판되어 왔으며 본인은 여기서 제7차로 개정된 NRC 사양표준(1977)에 발표된 요구량에 관련해서 몇 가지 분야를 검토하고자 한다. (중략)

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Comparative Study Between a Dynamic Food-Chain Model(DYNACON) and an Equilibrium Model (NRC Model)

  • Hwang, Won-Tae;Suh, Kyung-Suk;Kim, Eun-Han;Park, Young-Gil;Han, Moon-Hee
    • Proceedings of the Korean Nuclear Society Conference
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    • 1997.05b
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    • pp.407-412
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    • 1997
  • The predictive results between a dynamic food-chain model (DYNACON) and an equilibrium model (NRC model) were compared to show the physical validity of DYNACON. Although the mathematical formulations and transport processes of radionuclides in the environment are different between two models, the comparative study shows good agreement for deposition events that occur during the growing season of plants.

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1977년도 NRC 가금사양표준과 그 활용상의 문제점(상)

  • 이영철
    • KOREAN POULTRY JOURNAL
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    • v.10 no.8 s.106
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    • pp.79-93
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    • 1978
  • NRC는 가금영양에 관한 학술적 또는 실제적인 연구가 발전되고 종계의 능력이 개량됨에 따라 관계전문가들의 의견을 정리하여 사양표준을 개정 발행하고 있다. 이번 1977년판도 상당한 부분을 개정 발표하고 있다. 산란계 부로일러 육성추에 대한 아미노산 요구량을 일정한 에너지 함유사료중 $\%$로 표시하는 동시 Mcale당 아미노산 g 요구량도 표시되었다. 산란계 초생추 및 중추기간 단백질 요구량이 1$\~$2$\%$ 낮아졌고 부로일러도 과거 2단계 사육법이 3단계 사육법으로 바뀌었다.

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