• Nuclear Engineering and Technology
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• 제17권1호
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• pp.8-15
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• 1985

Debris bed내·외로부터 깨스유량을 갖는 debris/water 열적상호작용 해석모델이 중대사고 분석을 위해 제시되었다. 제시된 모델은 증기 소비, debris bed에서 수소 생성, 유입깨스 및 화학반응열에 대한 인자들을 포함하고 있으며, 금속-물반응 및 debris/concrete 작용으로 인한 깨스 생성을 평가하기 위해 MARCH code에 도입시켰다. 그 결과 수소원은 격납용기 과도압력에 큰 영향을 미치나 debris bed로 대류깨스 냉각과 콘크리트로 전도 열손실은 debris bed 냉각성에 조그마한 영향을 주는 것으로 나타났다. 하지만 debris 인자의 재가열과 재용융은 콘크리트와 상호작용에 의해 상당히 지연될 수 있다.

• 한방안이비인후피부과학회지
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• 제25권2호
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• pp.49-60
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• 2012

Objective : Acupuncture has been used for treating eye disease for thousands of years but there are few evidence based medicine (EBM) for its use. This study is a review of Clinical trials related to the treatment of eye disease by acupuncture therapy. Methods : We referred a Pubmed site by using searching word of "eye, acupuncture" (Limits: 10 Year, Clinical Trials, Humans, English). Results : Eight journals with twelve papers were searched. Eight of these studies were randomized and ten trials of acupuncture treatments reported significant effect. On the topic of these clinical trials, five of them were about dry eyes, four about disorder of refraction, two about intraocular pressure and one about visual function. The result of clinical studies represented the significant cure rate. Conclusion : We found that RCTs about the acupucnture for eye diseases were more and more published. But their average impact factor was 2.16 and average modified Jadad score was 3.89, so there needs more qualifying studies.

• Nuclear Engineering and Technology
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• 제46권1호
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• pp.39-46
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• 2014

A total loss of all heat sinks is considered a severe accident with a low probability of occurrence. Following a total loss of all heat sinks, the degasser/condenser relief valves (DCRV) become the sole means available for the depressurization of the primary heat transport system. If a nuclear power plant has a total loss of heat sinks accident, high-temperature steam and differential pressure between the primary heat transport system (PHTS) and the steam generator (SG) secondary side can cause a SG tube creep rupture. To protect the PHTS during a total loss of all heat sinks accident, a sufficient depressurization capability of the degasser/condenser relief valve and the SG tube integrity is very important. Therefore, an accurate estimation of the discharge through these valves is necessary to assess the impact of the PHTS overprotection and the SG tube integrity of the primary circuit. This paper describes the analysis of DCRV discharge capacity and the SG tube integrity under a total loss of all heat sink using the CATHENA code. It was found that the DCRV's discharge capacity is enough to protect the overpressure in the PHTS, and the SG tube integrity is maintained in a total loss of all heat accident.

• 한국추진공학회지
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• 제22권5호
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• pp.97-106
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• 2018

본 논문은 충격파 터널을 이용한 이중압축램프 흡입구 형상의 모델 스크램제트 시험에서 나타난 기술적 난제 및 그 해결 방안들을 정리하였다. 시험 설비 불시동, 격막 파편에 의한 유동 교란 및 모델 손상, 다중 분사에 따른 연료 제트 미발달, 그리고 짧은 시험 시간이 이에 해당한다. 파악된 기술적 난제들을 해결한 이후, 개선된 결과를 쉐도우그래프 이미지 및 저압관 끝단 전압력 측정 결과를 통해 확인하였다.

• 복식문화연구
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• 제27권2호
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• pp.181-192
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• 2019

The growth of cheap, industrial, mass-production-so-called "fast fashion"-has led to dramatic increases in levels of consumption. Inexpensive products tend to foster unsustainable consumption behaviors, which negatively impact the environment and increase pressure to obtain goods at lower and lower prices; this, in turn, has the competitive effect of decreasing wages. This study focused on the concept of socially responsible consciousness in relation to fashion products. Environmental and labor issue concerns were employed as major variables. Empirical data were collected from males and females, between the ages of 10 and 50. Demographic differences were found in SR consciousness. For example, participants in their 10s, 40s, and 50s had higher levels of SR consciousness than those in their 20s and 30s. In addition, consumers' levels of environmental and labor issue concerns had varying effects on the criteria they used to select clothing. Product category type was also an influential factor. Moreover, the analysis showed that SR consciousness was less important in the apparel industry than in the food sector. The study also found an attitude-behavior link in relation to the concept of SR consciousness. The link was stronger for environmental concerns than for labor issue concerns. This study aimed to develop a better understanding of current customers' characteristics and levels of SR consciousness.

• 지식경영연구
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• 제19권4호
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• pp.77-98
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• 2018

The purpose of this paper is examine the existing relations structure and IT use for collaboration activities on supply chain and their impacts on the performance of supply chain. This study made a design of the research model that was further constructed by integrating the relationship structure, IT exploration, IT exploitation, supply chain collaboration, absorptive capacity, and knowledge creation, efficiency and efficient. The survey data were collected from 378 companies, where firms are facing increased global competitive pressure and heavily utilize SCM to retain their competitive advantages. The authors validated a measurement model with structural equation modelling and tested eight hypotheses. As a result, the absorptive capacity was closely related to trust, IT exploitation and IT exploration, but supply chain collaboration. Examining the effect of supply chain collaboration with two types of absorptive capacity, the authors found positive effect on potential absorptive capacity, but a non-significant effect on realized absorptive capacity. This finding suggests that the improving performance of supply chain not only is related to the relations structure and IT use on supply chain, but also is closely related to the absorptive capacity.

• Asian-Australasian Journal of Animal Sciences
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• 제32권8_spc호
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• pp.1275-1283
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• 2019

Goats (Capra hircus) were domesticated during the late Neolithic, approximately 10,500 years ago, and humans exerted minor selection pressure until fairly recently. Probably the largest genetic change occurring over the millennia happened via natural selection and random genetic drift, the latter causing genes to be fixed in small and isolated populations. Recent human-influenced genetic changes have occurred through biometrics and genomics. For the most part, biometrics has concentrated upon the refining of estimates of heritabilities and genetic correlations. Heritabilities are instrumental in the calculation of estimated breeding values and genetic correlations are necessary in the construction of selection indices that account for changes in multiple traits under selection at one time. Early genomic studies focused upon microsatellite markers, which are short tandem repeats of nucleic acids and which are detected using polymerase chain reaction primers flanking the microsatellite. Microsatellite markers have been very important in parentage verification, which can impact genetic progress. Additionally, microsatellite markers have been a useful tool in assessing genetic diversity between and among breeds, which is important in the conservation of minor breeds. Single nucleotide polymorphisms are a new genomic tool that have refined classical BLUP methodology (biometric) to provide more accurate genomic estimated breeding values, provided a large reference population is available.

• International Journal of Naval Architecture and Ocean Engineering
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• 제11권1호
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• pp.530-541
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• 2019

To improve our current understanding of tsunami-like solitary waves interacting with a row of vertical slotted piles on a sloping beach, a 3D numerical wave tank based on the CFD tool $OpenFOAM^{(R)}$ was developed in this study. The Navier-Stokes equations were employed to solve the two-phase incompressible flow, combining with an improved VOF method to track the free surface and a LES model to resolve the turbulence. The numerical model was firstly validated by our laboratory measurements of wave, flow and dynamic pressure around both a row of piles and a single pile on a slope subjected to solitary waves. Subsequently, a series of numerical experiments were conducted to analyze the breaking wave force in view of varying incident wave heights, offshore water depths, spaces between adjacent piles and beach slopes. Finally, a slamming coefficient was discussed to account for the breaking wave force impacting on the piles.

• Nuclear Engineering and Technology
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• 제51권1호
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• pp.73-83
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• 2019

It is important to clarify the mechanisms of molten-fuel-pool sloshing behavior that might be encountered during a core disruptive accident of sodium-cooled fast reactors. In this study, motivated by acquiring some evidence for understanding the characteristics of this behavior at more realistic conditions, a number of experiments are newly performed by injecting nitrogen gas into a water pool with the accumulation of solid particles. To achieve comprehensive understanding, various parameters including particle bed height, particle size, density, shape, gas pressure along with the gas-injection duration, were employed. It is found that due to the different interaction mechanisms between solid particles and the gas bubble injected, three kinds of regimes, termed respectively as the bubble-impulsion dominant regime, the transitional regime and the bed-inertia dominant regime, could be identified. The performed analyses also suggest that under present conditions, all our experimental parameters employed can have noticeable impact on the regime transition and resultant sloshing intensity (e.g. maximum elevation of water level at pool peripheries). Knowledge and fundamental data from this work will be used for the future verifications of fast reactor severe accident codes in China.

• 한국IT서비스학회지
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• 제18권1호
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• pp.91-112
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• 2019

The IoT environment has led to explosive growth of existing enterprise data, and how to utilize such big data is becoming an important issue in the management field. In this paper, major factors affecting the decisions of companies to utilize big data have been studied. And also, the effect of big data utilization on the management quality is studied empirically. During this process, we have studied the difference according to the award of Korean national quality award. As a result of the study, we confirmed that the five factors such as cost from technology, organization and environment perspective, compatibility, company size, chief officer support, and competitor pressure are key factors influencing big data utilization. Also, it was confirmed that the use of big data for management activities has an important influence on the six management quality factors based on MBNQA, and that the management quality level of Korean national quality award companies is relatively high. This paper provides practical implications for companies' use of big data because it demonstrates for the first time that big data utilization has an impact on management quality improvement.