• Journal of the Korea Society for Simulation
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• v.29 no.2
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• pp.11-20
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• 2020

As the manufacturing environment becomes more complex, traditional simulation models alone are having a lot of difficulties in reflecting real-time manufacturing situations. Although the Digital Twin concept is actively discussed as an alternative to overcome theses issues, many studies are being carried out only in the product design phase. This research presents a Digital Twin-based manufacturing environment framework for applying the Digital Twin concept to the manufacturing process. Twin model that is operated in virtual space, physical system and databases describing the actual manufacturing environment, are proposed as detailed components that make up the framework. To check the applicability of proposed framework, a simple Digital Twin-based manufacturing system was simulated in a conveyor system using Arena software and Excel VBA. Experiment results have shown that the twin model is transmitted real time data from the physical system via DB and were operating in the same time unit. The Excel VBA fitted parameters defined by cycle time based on historical data that real-time and training data are being accumulated together. This study proposes operating method of digital twin model through the simple experiment examples. The results lead to the applicability of Digital twin model.

• Journal of Korean Society of Industrial and Systems Engineering
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• v.43 no.2
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• pp.72-78
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• 2020

Demand for cosmetics with functionality and eco-friendliness has increased dramatically due to recent aging, well-being trends, and increased interest in beauty. Cosmetics production in 2014 was 8,970.4 billion won, an increase of about 50% compared to 6,014.6 billion won in 2010. In the midst of this, similar companies in intense competition are pursuing differentiated strategies and innovation activities to solve quality, price and delivery problems. In particular, cosmetics packaging work is getting more difficult due to the increasing bill of materials (BOM) and difficult assembly methods. Therefore, in this study, the following problems were identified and suggestions for the improvement of the packaging Many research laboratories such as biotechnology, chemistry, and pharmaceuticals, which are undergoing various studies, are equipped with ready-made laboratory safety equipments such as bio-safety workbenches, aseptic bases, and exhaust workbenches. However, most researchers are disadvantaged in using existing safety equipment. This is because existing safety equipment can not take into account all of the unique characteristics of the research. For this reason, researchers are demanding the development of customized safety equipment that is well suited to their research needs. process of Company C, which is facing difficult situation to respond to the customer 's delivery due to the 52 - hour work week. First, we used the stopwatch to find the difficulty process in the packaging process and show ways to improve it. Second, to improve the efficiency of line balancing in the packaging process, we integrate processes, improve work methods, and perform simple automation. As a result, the prepare loss for replacement was reduced by 1 minute from 5 minutes, resulting in a 23% increase in productivity from 112 ea./hour to 137ea./ hour per person. At this time, the LOB of the packaging process was improved from 70% to 82% by operating one more production line through one person per line, total 9 people saving.

• Journal of the Korean Wood Science and Technology
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• v.49 no.5
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• pp.514-534
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• 2021

To estimate the territorial size of Reticulitermes speratus, a species of subterranean termites that damages wooden structures in Korea, appropriate dye markers were selected and the diffusion tendency was analyzed. According to the results of the sensitivity assessment using sawdust diet, increase in dye concentration reduced the amount of feed consumption but the dyeing becomes more intense. Except for the Neutral Red 0.5% group, all other concentration groups, including the control group, showed a survival rate of > 85% until week 4. For both, Nile Blue A and Neutral Red dye markers, all concentration conditions > 0.2%, except for the 0.1% concentration, were maintained for 11 weeks, and no sign of transfer effect was found except when the termites were fed with the dye markers. Therefore, it appears that 0.2% of Nile Blue A and Neutral Red is the optimal concentration for monitoring the R. speratus colonies. Additionally, we prepared an indoor 40 m long foraging arena consisting of a colony of 25,000 termites and released individuals stained with 0.2% of Nile Blue A and Neutral Red at both ends to assess the diffusion trends over time. The results showed that it took approximately 7 days for each dyed individual to gradually cover the 40 m distance and mix with each other. These findings reveal that when mark-release-recapture monitoring is conducted on the R. speratus colonies damaging wooden structures, the extent of the colony's activity area could be measured and different colonies could be distinguished from each other.

• Management Science and Financial Engineering
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• v.8 no.1
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• pp.21-38
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• 2002

Rapid advances in information technology(IT) and telecommunication systems impact the number and quality of decision-making in organizations. Specifically, middle mangers must posses or develop the creativity necessary for survival in a constantly changing and volatile business environment. While tradition and conventional wisdom tell us that a middle managers role centers on control and monitoring, todays competitive arena has spun out a new managerial requirement developing and maintaining an innovative attitude. Problematically, most previous research has focused on the issue of changing decision authority (i. e. centralization/decentralization). Moreover, much previous research has also largely ignored environmental changes exposing new roles that middle managers have assumed. This study explores the means of identifying middle managerial roles, managerial possibilities involving the growing popularity of open systems through electronic brainstorming, and an adaptation and development of Diffusion Theory and attempt to counter criticism leveled at the theory's inability to provide an adequate explanation for diffusion of complex organizational technology. This paper develops three ideas: 1) Introducing the 'Chasing Curve' as a theoretical background. 2) Suggesting a new methodology using electronic brainstorming for analyzing the gap between Knowing (the perceived importance of middle managers' roles) and Doing (the degree of current status of middle managers' roles), which we term the 'Spiral Gap Analysis Model'. 3) Identifying a feedback system for minimizing the Knowing - Doing gap, aimed at development of IT strategic priority decision support, which we call this the 'Star Process'.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.15 no.7
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• pp.4198-4211
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• 2014

The purpose of this study was to integrate the general education activities in the preschool developmental delay regarding the effect on the social skills of infant and young children. The participants of this research were young children with a developmental delay, who were enrolled in a school for the physically challenged in Gim-Hae City, South Kyongsangnamdo in Korea. An experimental qualitative module was selected to observe the social consequences after taking the extensive educational programs on young children with a developmental delay. The data was based on the observations of a researcher regarding the child's behavior and videotaped material was analyzed qualitatively in terms of the occasions and their social behaviors while extensive education was performed. The qualitative analysis explains the lower arena of the learning social skill including the quantitative changes in the communicational skill, and self-control skills.

• Journal of Distribution Science
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• v.16 no.11
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• pp.5-10
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• 2018

Purpose - The recent establishment of many varieties of English language in the globe has created many models of English such as world Englishes (WEs), English as a Lingua Franca (ELF), English as a family of languages, and English as an Intercultural Language (EIcL). Among the models, the present study highlights 'English as an intercultural language (EIcL)' in relation to distribution science business English teaching to elucidate what EIcL is and why it is critical and how it can be realized in the business English classrooms. Research design, data, and methodology - This study look into the EIcL paradigm that empowers all active users to view English as universal and at the same time enables them to develop critical skills to bridge intercultural gaps or to cross borders. Results - Rather than just focusing on an acquisition of standardized English(es), EIcL serves as a major contextual factor facilitating success in getting competence among the different English languages. Conclusions - EIcL is a promising and ultimately rewarding approach to the contemporary business English teaching arena. EIcL should be achieved through policies, textbooks or living abroad, and, above all, learners/teachers' active awareness and understanding' of the EIcL mainstreams.

• Asian Pacific Journal of Cancer Prevention
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• v.17 no.5
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• pp.2527-2533
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• 2016

Sensitising cancer cells and at the same time desensitizing normal cells is a double task in cancer management. Agents which can combat the debilitating side effects of cancer therapeutics and simultaneously synergize with anticancer agents in specifically targeting cancer cells are needed. Selenium, a proven anticarcinogen, gains due importance in terms of its efficacy to combat the side effects of cancer therapy. This study is a comparative analysis of the chemoprotective effects of selenium compounds, methyl selenol (generated from organic selenomethionine (5mmol/L ; METase 40U/L)) and sodium selenite (inorganic form)($30{\mu}M$) in peripheral blood human lymphocytes exposed to cisplatin and mitomycin. Biochemical alterations occurring in many cells during apoptosis include loss of plasma membrane phospholipid asymmetry, DNA fragmentation, and activation of caspase-3. The present study demonstrated that the selenium metabolite and selenite are efficient in protecting lymphocytes undergoing DNA damage and exerted their activity by reducing caspase 3 expression. Interestingly organic methylselenol (MeSe) was found to offer more protective effects compared to inorganic selenite (SeL), by reducing the induction of apoptosis by the cytotoxic agents. This suggests that MeSe and to a lesser extent selenite might have potential for assessment in clinical trials and could be considered as strong candidates in pharmacogenomics or in the nutriprotective arena.

• Journal of Korean Library and Information Science Society
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• v.40 no.3
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• pp.367-387
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• 2009

The similar bibliographic retrieval system follows whether it selects a thing of the extracted index term and or not the difference in which the similar document retrieval system There be many in the search result is generated. In this research, the method minimally making the error of the selection of the extracted candidate index term is provided In this research, the word information in which it is adjacent by using candidate index terms extracted from the similar literature and the keyword topic information were used. And by using the related author information and the reranking method of the search result, the similar bibliographic system in which an accuracy is high was developed. In this paper, we conducted experiments for similar bibliographic retrieval system on a collection of Korean journal articles of science and technology arena. The performance of similar bibliographic retrieval system was proved through an experiment and user evaluation.

• Korean journal of applied entomology
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• v.40 no.1
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• pp.44-49
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• 2001

Development and predation of an aphidophagous gall midge, Aphidoletes aphydimyza (Rondani) , on the green peach aphid, Myzus persicae Sulzer, were studied under laboratory and greenhouse conditions. The developmental threshold temperature of the gall midge larvae was estimated to be $13^{\circ}C$. Larval and total developmental periods were 5.3 and 29 days at 25 $\pm$$2^{\circ}C$. The gall midge attacked more aphids as increasing density of peach aphids, and consumed 4 out of 10 peach aphids per day in a petri dish (9 cm in diameter) at maximum. In green house, the gall midge could control the density of the green peach aphids efficiently with a delayed density dependent-like pattern.

• Journal of Information Technology Services
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• v.10 no.3
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• pp.31-47
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• 2011

With the saturation of the local market, the domestic media industry is searching for new growth drivers by crossing over to other industries, but due to the limited size of the market, results fail to meet expectations. Despite its strengths in cultural contents, as verified by the Korean Wave Hallyu, and advanced platform services, the industry feels threatened by the entry of global foreign media businesses in the domestic arena. This and the stagnated growth in the local media market are challenges we are facing today. On the other hand, it could prove to be a timely opportunity to transform the existing media industry structure where exporting hardware and terminals is at the heart of a globalized business into a structure based on software and contents exports. Based on such critical thinking, this study examines the current status of media markets, home and abroad, and aims to come up with strategic measures through a discussion on the issues and methods proposed for the globalization of local media businesses from a holistic viewpoint based on ecosystem, M&A and contents.