• Korean Chemical Engineering Research
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• v.51 no.2
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• pp.226-232
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• 2013

To produce biobutanol, fermentation processes using clostridia that mainly produce acetone, butanol and ethanol are used. In this work, a dynamic model describing the metabolic reactions in an acetone-butanol-ethanol (ABE)-producing clostridium, Clostridium acetobutylicum ATCC824, was proposed. To estimate the 58 kinetic parameters of the metabolic network model with experimental data obtained from a batch fermentor, we used an efficient optimization method combining a genetic algorithm and the Levenberg-Marquardt method because of the complexity of the metabolism of the clostridium. For the verification of the determined parameters, the developed metabolic model was evaluated by experiments where genetically modified clostridium was used and the initial concentration of glucose was changed. Consequently, we found that the developed kinetic model for the metabolic network was considered to describe the dynamic metabolic state of the clostridium sufficiently. Thus, this dynamic model for the metabolic reactions will contribute to designing the clostridium as well as the fermentor for higher productivity.

• Journal of the Korean Applied Science and Technology
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• v.36 no.4
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• pp.1188-1197
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• 2019

Exposure to stress can lead to sympathetic hyperactivity, which include a systemic disease with lesions in a broad spectrum of organs and a psychiatric condition. The purpose aimed to evaluate the effect of the korea ginger essential oil on stress hormone and brain tissue response in chronic mild stress-induced rats model of sympathetic hyperactivity. Evaluation method carried out cytotoxicity assessment and component analysis, what observe the effects based on serum biomarker and histopathological analysis of brain tissue. As this time, the korea ginger essential oil was treatment at doses of 100 nl/㎖ for 2 weeks after make a chronic mild stress-induced rats model of sympathetic hyperactivity. As a result, the korea ginger essential oil was not toxic at less than 100 nl/㎖, contents of 6-gingerol was 345 ppm. Compared to the control rats, the korea ginger essential oil treatments significantly reduced the serum concentrations of stress hormone (i.e., ACTH, corticosterone, melatonin). Furthermore, The korea ginger essential oil treatments effectively preserved the TH-immune response was occasionally interrupted in the ventral tegmental area (VTA) and the substantia nigra pars compacta (SNpc). The results indicate that the korea ginger essential oil improved sympathetic hyperactivity. Thus, the korea ginger may be a novel material of aroma oils for the management of sympathetic hyperactivity.

• Journal of Digital Convergence
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• v.15 no.8
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• pp.85-93
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• 2017

Kolao Holdings has a dominant market share in Lao Automotive market, wherever Japanese automotive makers have the biggest market share in other Southeast Asian countries. The company that was founded by a Korean in Laos has firstly listed on the Korean Stock Market among companies which Koreans founded abroad. Applying the model of Exploration and Exploitation by March(1991), this study is aiming at finding out what the management strategy leaded to Kolao's success in Laos. In addition, this study figured out the company's process innovation and cultural innovation. In result, it is summarized that the exploitation activities contributed to the entry to Lao market, the exploration activities to expanding market to neighboring countries, the process innovation to creation profits, and cultural innovation to sustainable growth.

• Proceedings of the Korea Society for Industrial Systems Conference
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• 2001.05a
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• pp.165-183
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• 2001

지난해부터 인터넷 분야에서 가장 확실한 수익 모델을 갖춘 사업 분야로 e-Learning 분야가 손꼽히면서 많은 온라인 교육 서비스가 우후죽순처럼 등장해 이미 1,000여 개의 서비스가 각축을 벌이고 있다. 그러나 e-Learning은 무엇보다도 학습용 컨텐츠의 품질이 그 성패를 좌우한다 할 때 한국의 온라인 학습 컨텐츠의 품질은 부실하기 이를 데 없다는 게 중론이다. 이는 S/W 공학에서 S/W 품질 보장을 위해 개발 방법론이 중요한 것으로 인식되는 것과 이를 지원하기 위한 Method II등 여러 도구들이 보급되고 있는데 비해 학습 컨텐츠는 그 중요도와 개발이 복잡하고 정교함이 요구됨에도 불구하고 개발 방법론에 대한 인식과 개발방법론을 지원하기 위한 도구가 없음에 기인하는바 크다 할 수 있겠다. 아직까지 국내에서는 MacroMedia Director나 ToolBook, Authorware등 일반적인 저작 도구나 웹 기반의 컨텐츠를 제작하는 Dreamweaver등의 HTML Editor만 있으면 컨텐츠가 만들어 질 수 있는 것으로 착각하고 있는 경우가 많다. 교육 학습용 컨텐츠의 개발 주기를 살펴보면 요구 분석->교수 설계->저작->평가->배포의 단계를 거치게 되는데 이때 학습 컨텐츠의 품질은 사실 요구 분석과 교수 설계 단계에서 결정되게 되며 이 학습 컨텐츠의 품질을 결정하는 단계에서는 IT 분야 지식보다는 오히려 교육 공학적 지식이 더욱 요구된다. 그러나 현실적으로 이 단계의 절차적 복잡성과 전문성으로 인해 거의 대부분의 학습 컨텐츠들이 제대로 개발 주기를 거치지 못하고 검증되지 않은 스토리 보드에 의한 저작 단계로 바로 돌입하고 있는 것이 한국의 실정이라 하겠다. 따라서 본 프로젝트에 의해 개발 된 교수 설계 도구는 교육/학습 컨텐츠의 품질 보증을 위한 방법론인 교육 공학의 체제적 교수 설계 이론 Model (Instructional System Design Model), 특히 그 중에서도 이 분야의 사실상의 표준 이론(de facto standard)인 Dick & Carey 교수와 Gagne 교수의 인지주의 ISD Model을 기반으로 정교한 교수 설계와 코스 맵 설계를 가능하게 함으로써 학습 컨텐츠의 품질 보증 활동을 지원 할 수 있는 도구로 개발하였다. 특히 Linux 기반에서 PHP로 개발 함으로써 Platform에 구애받지 않은 사용 환경을 구현 하였으며 향후 많은 e-Learning Platform에 교수 설계 모듈로 장착 함으로써 기존의 e-Learning Platform들의 가치를 높일 수 있는 계기가 될 것으로 생각한다.

• Journal of the Korean Data and Information Science Society
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• v.24 no.1
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• pp.135-150
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• 2013

This study proposes a novel option strategy by using characteristic of volatility reversion and rough set algorithm in options market. Until now, various research has been conducted on stock and future markets, but minimal research has been done in options market. Particularly, research on the option trading strategy using high frequency data is limited. This study consists of two purposes. The first is to enjoy a profit using volatility reversion model when volatility gap is occurred. The second is to pursue a more stable profit by filtering inaccurate entry point through rough set algorithm. Since options market is affected by various elements like underlying assets, volatility and interest rate, the point of this study is to hedge elements except volatility and enjoy the profit following the volatility gap.

• Journal of the Korea Institute of Information and Communication Engineering
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• v.18 no.12
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• pp.3005-3012
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• 2014

Massive Open Online Courses(MOOC), originally started from United States, have recently received a great deal of attention all over the world. MOOC means free online courses that anyone can attend anytime. In Korea, KERIS(Korea Education and Research Information Service) and some universities provide various MOOC services. The purpose of this paper is to present current status and improvement suggestions of MOOC. We first introduce the formal definition and history of MOOC, then discuss current status of MOOC services in Korea and other countries. We finally present improvement suggestions that include induction of active participation for universities, value creation for campus, development of revenue model, providing motivation to students for finishing courses, development of LMS(Learning Management System), securing well-trained lecturers, translation of lecture materials, ensuring quality of authentification system of MOOC services.

• Journal of Practical Engineering Education
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• v.8 no.1
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• pp.57-62
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• 2016

The purpose of this study is to provide the basic data and to construct education system by analizing the case of Japan on the lifelong vocational competency development utilizing the university. Japan has grown by the world leading technology and talented people. In a globalized world, In order to achieve economic growth, It is necessary to connect the Human resource development to the overall growth of the economy. After the law on policy implementation system for the Lifelong Learning Promotion is enacted. University of japan, the newly defined the philosophy of lifelong learning in the Fundamental Law of Education. Then, University of japan has induced people to actively participate in the lifelong vocational competency development. In this paper, we refer to the Shizuoka University in Japan and learning support program and we studied the method for the activation of improvement and field placement of the training capacity of field training using the case of Japan on the lifelong vocational competency development utilizing the university.

• The Journal of the Convergence on Culture Technology
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• v.7 no.4
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• pp.807-814
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• 2021

As economic activities decrease, and the stock market decline due to COVID-19, many people are jumping into stock investment as an alternative source of income. As people's interest increases, many stock price analysis studies are underway to earn more profits. Due to the variance observed in the stock markets, it is necessary to analyze each stock independently and consistently. To solve this problem, we designed and implemented models and services that analyze stock prices using a reinforcement learning technique called Asynchronous Advantage Actor-Critic(A3C). Stock market data reflected external factors such as government bonds and KOSPI (Korea Composite Stock Price Index) as well as stock prices. Our proposed work provides a web service with a visual representation of predictions of stocks and stock information through which directions are given to investors to make safe investments without analyzing domestic and foreign stock market trends.

• Journal of the Korea Society of Computer and Information
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• v.29 no.7
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• pp.139-148
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• 2024

In the post-pandemic era, the demand for online education platforms has surged, leading to increased consumer reliance on online reviews for decision-making. This study investigates the impact of Chinese online customer reviews on consumer purchase behavior in online education. By examining the role of trust, review sentiment, and the quantity and timeliness of reviews, the research aims to understand how these factors influence consumer decisions. By using regression model, findings reveal that negative reviews, timely feedback, and a higher volume of reviews positively affect consumer purchase decisions, while course pricing demonstrates an inverse relationship. Furthermore, cognitive and affective trust mediate the relationship between reviews and purchase behavior, highlighting a reverse U-shaped effect on consumer decision inclination. These insights provide valuable implications for online education providers, emphasizing the need to manage and leverage online reviews to foster consumer trust and improve sales performance.

• Journal of the Korean Society of Food Science and Nutrition
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• v.43 no.3
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• pp.374-380
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• 2014

In this study, the anti-inflammatory effects of Lespedeza cuneata extract on macrophages and wound-healing in wound-induced animal experiments were investigated. In an anti-inflammatory test, 0.1 mg/mL of Lespedeza cuneata extract did not affect growth of RAW 264.7 cells, and Lespedeza cuneata extract suppressed nitric oxide (NO) generation from inflammation-induced macrophages in a concentration-dependent manner. Wounds on the skin of rats were treated with vehicle containing Lespedeza cuneata extract (SSP), vehicle (SCO), and commercial ointment (CCO). The wound and scar sizes in the SSP group were significantly reduced in comparison to the SCO and CCO groups (P<0.05). The epidermis and dermis of the SSP group also recovered faster than the SCO group based on Masson's trichrome staining. The gene expression levels of vascular endothelial growth factor (VEGF) decreased and transforming growth factor-beta 1 (TGF-${\beta}1$) increased in wound tissue from the SSP group compared to that from the SCO group. These results show that Lespedeza cuneata extract accelerates wound-healing through anti-inflammatory activity and induction of collagen regeneration as well as reduces the scar area surrounding wounds. Accordingly, Lespedeza cuneata extract could be useful as a cosmeceutical in the cosmetic industry.