• 비파괴검사학회지
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• 제36권1호
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• pp.60-67
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• 2016

가압중수로는 운전중 연료교체가 가능하도록 설계된 연료관에서 핵분열을 유도하여 에너지를 얻는다. 연료관은 핵연료와 직접 접촉하며 원자로 냉각재의 통로인 압력관, 주위 감속재와 접촉하며 원자로에 확관된 원자로관, 이것을 양쪽에서 지지하는 엔드피팅과 압력관과 원자로관의 접촉을 방지하기 위한 스페이서 등으로 구성되어 있다. 연료관은 가장 안전성이 요구되는 설비이므로, 캐나다 기술기준 CSA N 285.4에 따라 주기적이고 철저한 가동중검사를 수행하여 건전성을 확인한다. 월성 중수로 연료관의 가동중검사를 수행하기 위해 연료관 검사시스템을 개발하였다. 본 논문은 월성 연료관 현장시험 결과를 검토하고, 개발된 연료관 검사시스템의 유효성을 확인하였다.

• 한국항행학회논문지
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• 제22권4호
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• pp.247-263
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• 2018

본 연구의 목적은 공항운영에서 다양성과 창의성 및 공기업경영평가 수행도가 공항성과에 어떠한 영향을미치고 있는지 실증연구를 통해 규명하고자 한다. 이를 위해, 본 연구의 문제는 다음과 같다. 첫째, 다양성이 창의성에 어떠한 영향을 미치고 있는가? 둘째, 다양성이 공항성과에 어떠한 영향을 미치고 있는가? 셋째, 창의성이 공항성과에 어떠한 영향을 미치고 있는가? 넷째, 창의성은다양성과 공항성과 간에서 매개효과가 유의한가? 다섯째, 공기업 경영평가 수행도는 다양성과 공항성과 간에서 조절효과가 유의한가? 이다. 연구결과 첫째, 다양성과 창의성에 관한 이론적 관계에 대해 어떤 관계가 있는지 설명하였다. 둘째, 내적 다양성이 창의성에 긍정적으로 유미한 영향을 미친다는 것을 실증적으로 밝혔다. 셋째, 창의성이 공항성과에 긍정적으로 영향을 미치는 것을 입증하였다. 넷째, 다양성과 공항성과 간에서 창의성이 간접효과가 유의한 것을 실증적으로 밝혔다. 다섯째, 공기업 경영평가 수행도가 다양성과 공항성과 간에서 유의미하게 조절한다는 것을 밝혔다.

• 한국사회복지학
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• 제51권
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• pp.141-156
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• 2002

본 연구의 목적은 사회적지지, 우울증, 그리고 성인자녀들과의 동거여부 사이의 관계를 조사하기 위해, 뉴욕에 거주하는 만 60세 이상인 한국 이민 노인 175명을 대상으로 면접조사를 실시하고 그 결과를 조사, 분석하였다. 미국에 거주하는 한국 이민 노인들의 가족들과의 별거여부와 우울증간의 관계에 있어서 사회적 지지의 역할을 정확히 이해하기 위해 공변량 구조분석을 이용하여 변인들간의 구조관계를 설명할 수 있는 최적의 이론구조모델이 선정되었다. 자료분석 결과, 미국내 한국 이민 노인들의 우울증 완화에 긍정적 영향을 미치는 사회적 지지의 역할을 설명함에 있어서 가족들과 떨어져 생활하는지의 여부가 한국노인들에게 중요한 역할을 한다는 완충효과 가설(buffering-effect hypothesis)이 직접적 효과 가설(direct-effect hypothesis)보다 더욱 적절한 대안임이 검증되었다. 그러므로, 미국 내 아시아계 이민노인들의 심리적 건강을 증진시키기 위한 사회교육 및 지역사회 참여활동 프로그램이 실질적인 효과를 거둘 수 있도록 해당 성인자녀가족이 함께 참여할 수 있는 서비스를 개발, 확충함은 물론, 높은 우울증세를 보이는 노인들에 대해서는 그들의 어려움을 이해하고 위로, 격려해 줄 대상확보가 중요한 것으로 방안이 제시되었다.

• Nuclear Engineering and Technology
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• 제22권1호
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• pp.1-11
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• 1990

중수는 중수형 원자로의 감속재 및 냉각재로 사용되고 있으며 그 가격이 고가이기 때문에 일단 계통내에서 사용된 후 농도가 낮아진 저등급 중수는 중수승급기를 통해 99.8% 이상으로 농축 재생되어 중수로로 재주입되고 있다. 본 연구에서는 중수승급기의 공정을 면밀히 검토하였고 정상상태의 중수증류공정의 해석을 위하여 이론적인 모델을 제시하였으며 변수들간의 관계식을 설정하였다. 그리고 이 비선형 관계식을 단계적으로 처리하는 알고리즘의 전산 프로그램 UPGR을 개발하였다. 전산코드의 결과는 실제 운전 데이타와 잘 일치하였다. 월성 1호기에서 이를 이용한 운전지침의 제시, 운전효율의 평가, 성능평가 및 성능관리를 수행함으로써 중수승급기의 효율적인 운전에 기여하고 있다.

• Nuclear Engineering and Technology
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• 제14권2호
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• pp.86-91
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• 1982

1977년 집합체 cell 중심간의 간격을 53.34cm(162 연료 집합체 저장)에서 36cm(562 연료 집합체저장)로 줄임으로 고리 1호기 부속 기사용 연료 저장 용량을 화장하였다. 확장된 저장 시설에 대하여 Monte Carlo방법을 이용한 KENO-IV코드로 Core Performance Branch에서 제시한 비정상적인 냉각수 밀도 조건에 따라 유효증배계수를 구하였다. KENO-IV결과 밀도 0.1143g/cm에서 최대유효 증배계수 0.9958$\pm$0.0048을 얻었고, 이 값은 US NRC 기준과 CPB기준인 0.98을 초과하므로 새로운 집합체 cell중심간의 간격을 구하였다. 이 과정은 KENO-IV보다 보수적인 결과를 나타내는 확산 코드 KIDD를 이용하여 cell중심간의 간격에 따른 상관 연구로부터 새로운 cell중심간의 간격을 얻었다. 이로부터 현재의 집합체 cell중심 간의 간격 36cm를 43cm 이상으로 늘려야 비정상적인 냉각수 밀도의 감소로 인한 사고의 경우에도 안전함을 알았다.

• Nuclear Engineering and Technology
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• 제47권7호
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• pp.791-803
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• 2015

The effective cross sections (XSs) in the direct whole core calculation code nTRACER are evaluated by the equivalence theory-based resonance-integral-table method using the WIMS-based library as an alternative to the subgroup method. The background XSs, as well as the Dancoff correction factors, were evaluated by the enhanced neutron-current method. A method, with pointwise microscopic XSs on a union-lethargy grid, was used for the generation of resonance-interference factors (RIFs) for mixed resonant absorbers. This method was modified by the intermediate-resonance approximation by replacing the potential XSs for the non-absorbing moderator nuclides with the background XSs and neglecting the resonance-elastic scattering. The resonance-escape probability was implemented to incorporate the energy self-shielding effect in the spectrum. The XSs were improved using the proposed method as compared to the narrow resonance infinite massbased method. The RIFs were improved by 1% in $^{235}U$, 7% in $^{239}Pu$, and >2% in $^{240}Pu$. To account for thermal feedback, a new feature was incorporated with the interpolation of pre-generated RIFs at the multigroup level and the results compared with the conventional resonance-interference model. This method provided adequate results in terms of XSs and k-eff. The results were verified first by the comparison of RIFs with the exact RIFs, and then comparing the XSs with the McCARD calculations for the homogeneous configurations, with burned fuel containing a mixture of resonant nuclides at different burnups and temperatures. The RIFs and XSs for the mixture showed good agreement, which verified the accuracy of the RIF evaluation using the proposed method. The method was then verified by comparing the XSs for the virtual environment for reactor applicationbenchmark pin-cell problem, as well as the heterogeneous pin cell containing burned fuel with McCARD. The method works well for homogeneous, as well as heterogeneous configurations.

• 한국학교ㆍ지역보건교육학회지
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• 제18권2호
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• pp.27-42
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• 2017

Objectives: The purpose of this study was to investigate the characteristics of smoking prevention programs and their effectiveness for Korean school-aged children and adolescents by using systematic review and meta-analysis. Methods: Electronic searches were performed in RISS, NAL, DBPia, KISS using keywords according to inclusion criteria. 21 studies published from 2003 to the first half of 2017 that dealt with effects of smoking prevention programs for school-aged children and adolescents were selected for systematic review. Results: All 21 studies were quasi-experimental research designs. More than half of the programs(66.7%) were conducted for male and female. Most of the programs were conducted more than once a week(71.4%). 14 studies(66.7%) did not report using a theoretical model. Five dependent variables(knowledge of smoking, attitude toward smoking, non-smoking intention, self-assertiveness, and self-efficacy) were selected to measure the effectiveness of the smoking prevention programs. Knowledge of smoking was the most effective at hedge's g=0.673. Self-efficacy and self-assertiveness variables were statistically significant at hedge's g=0.461 and hedge's g=0.279, respectively. Effect sizes of attitude toward smoking and non-smoking intention were not statistically significant compared to the control group. As a result of the moderator effect analysis on the knowledge of smoking variable, the statistically significant variables were 'gender of participants'(p<0.01) and 'duration of the program'(p<0.001). Conclusions: The results of this study using systematic review and meta-analysis will be evidence-based data for researchers conducting smoking prevention programs in school-aged children and adolescents.

• 동아시아경상학회지
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• 제9권4호
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• pp.1-15
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• 2021

Purpose - In a difficult time for a firm, it seems impossible to change circumstances by a firm. Nevertheless, the firm must do whatever it can do by however it can do. Therefore, the purpose of this study is to analyze the effect of HRM practice on organizational effectiveness with the status quo of the firm as a moderator. Based on the result of this study, the managerial implication could be suggested as a contextual response to each status quo of the firm in improving and managing organizational effectiveness by HRM practice. Research design, data, and methodology - This study measured organizational effectiveness with employee satisfaction and organizational commitment. HRM practice includes two HR management areas, HR system, and HR attitude. HR system includes education & training and additional wage welfare. HR attitude includes employee stress and empowerment. As for the status quo of the firm, this study considered three construct; firm feature, strategic feature, environment change feature. This study analyzed 397 employees of 24 company data from the 7th HCCP of KRIVET. Result - Hypothesis 1 through Hypothesis 3 were partially supported. The results of this study suggest that to increase organizational effectiveness(job satisfaction and organizational commitment), employee stress and education & training participation need to be managed. And circumstance of an organization as given the Status Quo of the firm needs to be managed differently like firm size, environment change in demand, and technology. Conclusion - This study suggests best-practice implications based on the result between HRM practice and organizational effectiveness. And also suggest differentiation in management to increase the best-fit in management.

• Nuclear Engineering and Technology
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• 제53권7호
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• pp.2104-2125
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• 2021

This paper presents the verification and validation (V&V) of a calculation module for isotope inventory prediction to control the back-end cycle of spent nuclear fuel (SNF). The calculation method presented herein was implemented in a two-step code system of a lattice code STREAM and a nodal diffusion code RAST-K. STREAM generates a cross section and provides the number density information using branch/history depletion branch calculations, whereas RAST-K supplies the power history and three history indices (boron concentration, moderator temperature, and fuel temperature). As its primary feature, this method can directly consider three-dimensional core simulation conditions using history indices of the operating conditions. Therefore, this method reduces the computation time by avoiding a recalculation of the fuel depletion. The module for isotope inventory calculates the number densities using the Lagrange interpolation method and power history correction factors, which are applied to correct the effects of the decay and fission products generated at different power levels. To assess the reliability of the developed code system for back-end cycle analysis, validation study was performed with 58 measured samples of pressurized water reactor (PWR) SNF, and code-to-code comparison was conducted with STREAM-SNF, HELIOS-1.6 and SCALE 5.1. The V&V results presented that the developed code system can provide reasonable results with comparable confidence intervals. As a result, this paper successfully demonstrates that the isotope inventory prediction code system can be used for spent nuclear fuel analysis.

• Journal of Korea Trade
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• 제25권7호
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• pp.75-91
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• 2021

Purpose - Social commerce (SC) is the growth of social media highlighting the e-commerce transactions and currently, the greatest challenges of e-commerce have attracted the influence of trust in social commerce intention (SCI). Based on the challenge, the study's purpose is to discover the effect of social support (informational and emotional support) on the SCI. The study also explores the mediation effect of trust and the moderation impact of culture between the USA and Korea. Design/methodology - This study used a sample of 482 surveys filled out by online shoppers from the US and Korea, two countries with divergent cultural values. Structural equation modelling (SEM) is used to analyze the hypothetical paths. In addition, bootstrapping and multi-group analysis are perform to view mediation and moderation effects respectively. Findings - The results of our study shows that both informational and emotional support significantly influences trust and SCI. Our results also supports the mediating effect of trust in social support and the moderating effect of culture in forming SCI. Originality/value - Our empirical results provide important information to businesses formulating cross-cultural SC strategies. This will help SC companies to analyze the aspects of customer trust through social support, which in turn will increase SCI and thereby established a competitive position for SCs. Our results will also be holistic directions for SC vendors in cross-cultural settings, which will offer important social and economic contributions to the sustainable growth of SC's business.