• The Korean Journal of Food And Nutrition
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• v.14 no.3
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• pp.255-262
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• 2001

랩포장 및 진공포장이 냉장 돈육이 저장성에 미치는 영향을 조사하기 위해 돈육의 등심부의를 랩포장 및 진공포장한 후 냉장저장하면서 저장기간에 따른 세균수,휘발성 염기질소, pH, 보수력 드립감량, 가열감량 및 경도의 변화를 측정하였다. 랩포장의 경우 일반세균수는 저장 10일에 2.0$\times$$10^{7}$ CGU/㎤의 수준에 달하였고, 휘발성 염기질소 함량은 저장 15d일에 26mg%로서 식육의 부패수준인 20mg%를 초과하였으며 , pH는 저장 7일 이후 급속하게 증가되어 저장 10일에 5.98의 수준이었다. 반면에 진공포장의 경우에는 일반세균수가 저장 30일에 7.7$\times$$10^{6}$ CGU/㎤의수준에 달하였고, 휘발성 염기질소 함량은 저장 30일에 19.8mg%로서 부패수준인 20mg%에 근접하였으며, pH는 저장기간이 경과됨에 따라 매우 완만하게 증가되어 저장 30일에 pH5.75의 수준이었다. 보수력은 저장 1일에는두 시험구가 75.0%의 수준으로 비슷하였으나, 저장기간이 경과됨에 따라 랩포장이 진공포장에 비해 급속하게 증가되었다. 드립감량과 가열감량은 저장초기인 저장 7일까지는 진공포장이 랩포장에 비해 다소 높은 수준이었으나 그 이후에는 랩 포장이 높은 수준이었다. 경도는 두 시험구 모두 저장 1일에 가장 높았고, 저장 기간이 경과됨에 따라 점차 저하되었으며, 랩포장에 비해 전공포장이 비교적 완만하게 저하되었다.

• The Journal of the Korea Contents Association
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• v.18 no.11
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• pp.455-461
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• 2018

This paper presents experimental investigations about flexural strength and durability of reinforced concrete beams repaired using ductile fiber reinforced cementitious composite (DFRCC) and carbon fiber sheet through freezing and thawing test. Total 14 RC beams of $100{\times}100{\times}400mm$ size were tested by 3-point bending and freezing and thawing test by KS F 2456. The beams were reinforced using 3D10 steels on both the tensile and compressive sides, and repaired on 3 sides expect on top cycle. Test results showed that the beams repaired using fiber carbon sheet revealed about 15% higher values of flexural strength compared than the cases of DFRCC motar. On the other hand, the results did not showed meaningful differences in the aspect of durability. For further research, consideration of the steel interference effect and real old specimens such as taken from real deteriorated structures are needed to be tested after repairing with DFRCC and carbon fiber sheet.

• The Journal of the Korea Contents Association
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• v.22 no.4
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• pp.314-323
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• 2022

This study examines the effecs of National Pension Service blockholders on accounting conservatism. The sample consists of 10,117 non-banking firm-years listed in Korea Stock Exchange(KOSPI) during the period 2011 to 2018. The results of this study are as follows. First, it was found that companies in which the National Pension Service as a major shareholder hold more than 5% of the shares are less prone to conservative accounting treatment than those that do not. Second, such a negative relationship between investment by the National Pension Service and conservative accounting was consistently found even when the investment period of the National Pension Service was divided into short-term (less than 1 year) and long-term (more than 3 years). It is expected that the National Pension Service, the largest institutional investor in Korea, will be able to carry out meaningful management control activities on investment companies. As the monitoring function of the National Pension Service works effectively in the capital market, agency costs are reduced, and investors' demands for corporate conservative accounting have decreased.

• KSCE Journal of Civil and Environmental Engineering Research
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• v.29 no.5A
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• pp.503-510
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• 2009

Latex modified concrete (LMC) is a successful polymer-portland cement concretes, which have been developed and used for many years, in overlaying bridge decks and resurfacing industrial floors. The excellent bond strength to substrate, easy application and high resistance to impact, abrasion, wear, aggressive chemicals and freeze-thaw deterioration have made this material used widely. The objective of this study was to determine experimentally the load-deflection response and ultimate strength of reinforced RC beams. The cracking patterns and the mode of failure were observed. Because of excellent bond strength and repairing effects, the RC beams repaired by LMC at compression or tension zone showed over 100% recovery from damaged structures. The RC beams overlaid by LMC showed significant improvement at load carrying capacity as overlay thickness increases. However, the beams repaired of tension zone without shear stirrups almost showed no strengthen effect, and indicated an interfacial failures. The interfacial behavior was estimated by numerical method adopting the concept of shear flow.

• Journal of the Korean Society for Railway
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• v.20 no.2
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• pp.275-287
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• 2017

During the feasibility study of new rail lines, maintenance cost of railway infrastructure has mostly been estimated based on the track length and on simplified parameters; however, the estimation reliability can be improved by employing the correction factor from UIC 715, as well as the line classification in UIC 714. The correlations between maintenance cost and various parameters such as weighted track length based on line classification, radius of curvature, gradient and worn -out rate have been analyzed according to the case studies. Prediction of the maintenance cost has been carried out using the cost data, which were representative of the whole cost data; as a result, it was demonstrated that a cost model based on the line classification and the correction factor was more reliable than the existing models. Furthermore, possibilities of using data from both the track measurement vehicle and from the maintenance information system, which are under development, have been investigated and, based on this investigation, a combined cost model using line classification, radius of curvature, gradient and worn-out rate, among other factors, will be proposed in the near future.

• Journal of Korea Society of Industrial Information Systems
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• v.27 no.4
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• pp.115-126
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• 2022

Under the COVID-19 pandemic, the importance of Official Development Assistance(ODA) in health and medical service is emphasized more. The number of cases is expected to increase in the future. Therefore, it is necessary to provide differentiated education and training for each type of occupation as a follow-up to realize the operations management and maintenance of medical equipment supported by the ODA project. In this study, for an effective follow-up and operations management of medical equipment supported by the ODA project, the differences in educational training achievement between users and maintainers were analyzed through a t-test. As a result of this study, there were significant differences between users and maintainers of medical equipment in use and manage six types of priority management target medical equipment(Q5) and an instruction manual understanding of medical equipment(Q6). However, there was no difference in the need and purpose of education and training, satisfaction with an instructor, and the need for cross-professional communication.

• Journal of the Korea Institute of Building Construction
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• v.24 no.1
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• pp.23-34
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• 2024

This research aims to assess the flexural bonding efficacy of polymer-cement composites(PCCs) in mending cracks within reinforced concrete(RC) structures. The study involved infilling PCCs into cement mortar cracks of varying dimensions, followed by evaluations of enhancements in flexural adhesion and strength. The findings indicate that the flexural bond performance of PCCs in crack repair is influenced by the cement type, polymer dispersion, and the polymer-to-binder ratio. Specifically, the use of ultra-high early strength cement combined with silica fume resulted in an up to 19.0% improvement in flexural bond strength compared to the application of ordinary Portland cement with silica fume. It was observed that the augmentation in flexural strength of cement mortar filled with PCCs was significantly more dependent on the depth of the crack rather than the width. Furthermore, PCCs not only acted as repair agents but also as reinforcement materials, enhancing the flexural strength to a certain extent. Consequently, this study concludes that PCCs formulated with ultra-high early strength cement, various polymer dispersions, silica fume, and a high polymer-to-binder ratio ranging from 60% to 80% are highly effective as maintenance materials for crack filling in practical settings.

• The Journal of the Korea Contents Association
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• v.15 no.7
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• pp.544-554
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• 2015

This study is effect of Hotelier's job environment on emotional exhaustion, job satisfaction and turnover intention. For data analyses, a total of 250 questionnaire were distributed Among them, 202 survey data were used for analyses. This study obtained following results. First, it found that fee, colleagues and atmosphere had the negative effects on the emotional exhaustion. Second, promotion, fee, colleagues and atmosphere had the positive effects on the job satisfaction. Third, fee, colleagues and atmosphere had the negative effects on the turnover intention. Fourth, emotional exhaustion had the negative effects on the job satisfaction. Fifth, Hotelier's emotional exhaustion had the positive effects on the turnover intention. Finally, Hotelier's job satisfaction had the negative effects on the turnover intention.

• Nuclear industry
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• no.1112 s.10
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• pp.59-61
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• 1982

국제원자력기구(IAEA)의 아시아지역에서의 원자력과학기술협력협정(RCA)은 금년으로 10년을 맞이했다. 현재, 이 협정에 따라 동남아시아 여러 나라에서는 식품조사, 방사선계측기의 보수 등의 프로젝트와 UN개발계획 (UNDP)과의 협력에 의한 공업이용프로젝트가 활발하게 진행되고 있다.

• 전기의세계
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• v.39 no.10
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• pp.57-63
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• 1990

당초는 석유 대체에너지의 개발로서 출발했던 Sunshine 계획이었지만 최근, 지구의 환경분제 특히 온실효과 문제에 대해서도 유효한 태양광발전의 기술개발을 적극적으로 추진하여 먼저 연료수송이나 운전.보수에 소요시간이 걸려 발전단가가 비싼 디젤발전에 의존하고 있는 낙도나 산간벽지에 도입을 시도할 필요가 있다고 생각하고 있다.