• The Journal of Korean Medicine
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• v.29 no.1
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• pp.106-116
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• 2008

Objectives : Peroxynitrite $(ONOO^-)$, superoxide anion radical $({\cdot}O_2^-)$ and nitric oxide (NO) are cytotoxic because they can oxidize several cellular components such as proteins, lipids and DNA. They have been implicated in the aging processes, and age-related diseases such as Alzheimer's disease, rheumatoid arthritis, cancer and atherosclerosis. The aim of this study was to investigate the $ONOO^-$, NO, and $({\cdot}O_2^-)$ scavenging and anti-inflammatory activities of Mori Fructus in ob/ob mice. Methods : Mice were grouped and treated for 5 weeks as follows. Both the normal lean (C57/BL6J black mice) and control obese (ob/ob mice) groups received the standard chow. The experimental groups were fed a diet of chow supplemented with 7.5, 15 and 30 mg Mori Fructus per 1 kg of body weight for 14 days. For this study, the fluorescent probes, namely 2',7'-dichlorodihydrofluorescein diacetate (DCFDA), 4,5-diaminofluorescein (DAF-2) and dihydrorhodamine 123 (DHR 123) were used. Western blotting was performed using anti-phospho $I{\kappa}B-\alpha$, anti-IKK-$\alpha$, anti-NF-${\kappa}B$ (p50, p65), anti-COX-2 and anti-iNOS respectively. Results : Mori Fructus inhibited the generation of $ONOO^-$, NO and $({\cdot}O_2^-)$ in the lipopolysaccharide (LPS)-treated mouse kidney postmitochondria in vitro. The generation of $ONOO^-$, NO and $({\cdot}O2^-)$ were inhibited in the Mori Fructus-administered ob/ob mice groups. The GSH/GSSG ratio decreased in the ob/ob mice, whereas they improved in the Mori Fructus-administered groups. Mori Fructus inhibited the expression of phospho $I{\kappa}B-\alpha$, IKK-$\alpha$, COX-2, iNOS genes, and thereby the activation of NF-$I{\kappa}B$. Conclusions : These results suggest that Mori Fructus is an effective $ONOO^-$, $({\cdot}O_2^-)$ and NO scavenger, and therefore it might be a potential therapeutic drug against the inflammation process and inflammation-related diseases.

• Journal of Power System Engineering
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• v.19 no.2
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• pp.49-56
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• 2015

As an alternative fuel that can be used in SI engine, LPG is one of clean fuels with larger H/C ratio compared to gasoline, low $CO_2$ emission, and small amount of pollutants such as sulfur compounds. When LPG is used in spark ignition engine, volumetric efficiency of the engine can be improved and pumping loss can be reduced by performing direct injection into the combustion chamber instead of port fuel injection. LPG-DI engine allows for lean combustion and stratified combustion under low load. In case of stratified combustion, air fuel ratio can be greatly increased compared to theoretic mixture ratio combustion. Improved thermal efficiency of the engine and reduced pumping loss can be expected from stratified combustion. Accordingly in this study, an experimental apparatus for visualization was designed and manufactured to study the combustion process of LPG after injection and ignition, intended to examine ignition probability and combustion characteristics of spark ignition direct injection(SIDI) LPG fuel. Ambient pressure, ambient temperature and fuel injection pressure were found as important variables that affect ignition probability and flame propagation characteristics of LPG-air mixture. Also, it was verified that the injected LPG fuel can be directly ignited by spark plug under appropriate ambient conditions.

• Journal of Digital Contents Society
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• v.13 no.3
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• pp.359-371
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• 2012

The coffee market has been rapidly growing up recently as well as the coffee industry which makes the number of educational institutions increasing in Korea. On the other hand, the classes lean too much on the practical exercise so the coffee education is urgently needed to define precisely and systematize academically. This study is accomplished on the basis of the teachers and students requirement analysis. The features that sets this study apart from the existing educational digital media is that the definite teaching-learning methods and teaching strategies were developed first. Furthermore, the physical and chemical phenomenon of coffee brewing were simulated by 3D animation software based on the visual languages. The general process of this media production was composed by the mutual relationship of the teacher's needs, educationist's strategies and media producer. After applying the digital media to students in the lesson of coffee science theory it was effective to increase their concentrativeness, interesting and learning motive. This media is also receiving the positive evaluation by the teachers to help the students in understanding the coffee science.

• Korean Journal of Construction Engineering and Management
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• v.8 no.3
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• pp.57-65
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• 2007

Last Planner System (LPS) developed by Lean Construction Institute consists of four steps: Master Schedule, Phase Schedule, Lookahead Planning and Weekly Work Plan. This paper focuses on the process of measuring Percent of Plan Completed (PPC) at the weekly Work Plan stage. PPC means the percentage of weekly assignments completed. According to the results of the researches that deal with PPC from many other countries, we can assure the benefits or using PPC. However the concept of PPC is unfamiliar in Korea construction industry. This paper analyzes the cases in which PPC is applied in other countries and compares them with the production control system in Korean construction industry. The results of this research will provide the time management system for using PPC in Korea.

• Korean Journal of Construction Engineering and Management
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• v.7 no.4 s.32
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• pp.146-153
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• 2006

The Last Planner(LP), of which the goal is to improve work-flow reliability, has recently been introduced in Korea. It is found that some contractors have made efforts on applying the Last Planner to their projects. However, they face difficulties for a variety of reasons. This paper presents the case study results on Korean heavy civil projects, along with descriptions of the ways that the Last Planner was applied, and how the work flow reliability was improved. It also discusses the prerequisites and barriers to implementation of the Last Planner in applying heavy civil construction projects in Korea. The results can be used as a reference for companies to improve their work flow reliability for future projects.

• Journal of the Korean Society of Combustion
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• v.18 no.2
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• pp.32-41
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• 2013

This study presents both experimental and numerical investigation of ignition delay time of n-heptane and n-butanol binary fuel. The $O_2$ concentration in the mixture was set to 9-10% to make high exhaust gas recirculation( EGR) rate condition which leads low NOx and soot emission. Experiments were performed using a rapid compression machine(RCM) at compressed pressure 20bar, several compressed temperature and three equivalence ratios(0.4, 1.0, 1.5). In addition, a numerical study on the ignition delay time was performed using CHEMKIN codes to validate experimental results and predict chemical species in the combustion process. The results showed that the ignition delay time increased with increasing the n-butanol fraction due to a decrease of oxidation of n-heptane at the low temperature. Moreover, all of the binary fuel mixtures showed the combustion characteristics of n-heptane such as cool flame mode at low temperature and negative-temperature-coefficient(NTC) behavior. Due to the effect of high EGR rate condition, the operating region is reduced at lean condition and the ignition delay time sharply increased compared with no EGR condition.

• Journal of Nutrition and Health
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• v.46 no.4
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• pp.307-314
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• 2013

Resveratrol (RSV) exerts several beneficial effects on metabolism and metaflammation-related diseases, including diabetes and non-alcoholic fatty liver disease (NAFLD). The purpose of this study is to investigate whether RSV affects pathophysiology of diabetes and NAFLD as well as hepatic autophagy in a rodent model of diet induced obesity (DIO). DIO was induced in a subset of C57BL/6J mice fed a high fat (HF, 45% kcal fat) diet. After six weeks of HF diet treatment, RSV (8 mg/kg/day) was administered via an osmotic pump for a period of four weeks. Therefore, the experimental groups were as follows: 1) lean control (CON), 2) HF diet-induced obese control (HF), and 3) HF_RSV. Body weight and food intake were monitored daily. Fasting glucose, insulin, and adiponectin in serum and lipid profiles in serum and liver were analyzed. In addition, the autophagic process was investigated using transmission electron microscopy (TEM). Body weight and food intake were not affected by RSV treatment. Impaired glucose control accompanied by DIO was recovered with RSV as shown by lower levels of fasting serum glucose and insulin when compared with HF obese controls. In addition, RSV treatment resulted in increased levels of serum adiponectin, however, indices of lipid profile in serum and livers were reduced. Results of TEM analysis showed that a HF diet induced excessive autophagy with the presence of double-membrane autophagosomes, which was ameliorated by RSV. The regulatory effect of RSV on autophagy was confirmed by the altered LC3-II formation, which increased with a HF diet and was decreased by RSV treatment. These results suggest that RSV treatment improves glucose control and lipid profile and these beneficial effects may be mediated by an altered autophagic process.

• Journal of Digital Convergence
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• v.16 no.11
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• pp.221-230
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• 2018

Most of researchers and business futurists agree that traditional organizational designs are inadequate for coping with today's turbulent and increasingly networked world. Executives in small firms find that their organizations must tap into an extended network of partners to achieve the scale and power needed to succeed in industries dominated by large, global firms. As they attempt to build lean yet agile businesses, these executives are finding that they no longer rely on gut instinct alone. Neither can they simply copy organizational model that worked in the past. They must understand how organizational design choices influence operational efficiency and flexibility and, even more important, how to best align the organization with the environment and the strategy chosen to quickly and effectively sense and respond to opportunities and threats This research examines the capabilities required to build businesses that can survive and prosper in today's fast-faced and uncertain environment. The insights presented in this research have emerged from over 30 years of work with hundreds of executives and entrepreneurs as they struggled to build businesses that could cope with the demands of a rapidly changing, networked global economy. The insights from this research suggest that IT is an important enabler for developing the best capabilities required for success.

• The Journal of Information Systems
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• v.30 no.4
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• pp.173-202
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• 2021

Purpose This study explored overall phenomena in context such as YouTube channel operation, strategy, and profit generation through interviews with two research participants who started their own businesses and are recognized as influencer on YouTube and analysis of viewer responses to uploaded contents. With the explosive growth of YouTube content provision and use, previous studies on YouTube are only being conducted individually on YouTube's content, influence, and content providers, so it is need to explore YouTube channel operations and the effect of revenue generation in context from an integrated perspective. Therefore, the purpose of this study is to present an integrated model that provides a specific process by contextually linking the factors and results influencing YouTube channel operation and revenue generation phenomena to individuals and companies who are trying to operate YouTube channels for the first time. Design/methodology/approach This study systematized and structured the overall phenomena in context such as YouTube channel operation, communication strategy, effect on revenue generation, and YouTube channel operation results by selecting interview subjects and collecting data through interviews, and analyzing viewer reactions (likes, comments, etc.). Due to the lack of previous studies exploring integrated phenomena, research analysis used Strauss & Corbin (1998)'s grounded theory approach, which presented inductive research methods to discover new theories by structuring concepts and categories based on detailed observations and information provided by interviewees. Findings The academic implication of this study is that while previous studies are conducted as individual studies on YouTube's content, influence, and content providers in the current situation where YouTube content provision and use are exploding, it integrally explores and presents an integrated model throughout the process. In addition, taking into account the lack of previous studies, it can be found in the aspect of using the grounded theory approach, an inductive theory approach that establishes a new theory. The practical implications can be found in that it presented practical directions to beginners who want to start operating YouTube channels by identifying operational preparations, communication strategies with viewers, and response management strategies.

• Journal of Technology Innovation
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• v.5 no.2
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• pp.1-21
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• 1997

The objective of this paper is to think about what structural reforms of the Korean government S&T development management system might be. Korean society is currently experiencing a drastic socio-economic transformation. The results of this transformation should be reflected on the determining process of the directions and breadths of structural reforms of government S&T development management system. Because the government system design will be based on the premises of socio-economic conditions under which administrative activities perform and also this socio-economic changes can influence on changes of the premises of government management system design. Moreover, S&T development management system is a subsystem of government system so that the directions of structural reform of those subsystems should be considered in the broad framework changes in the development management system of the government. For the last forty years, the Korean government S&T development management system has been based on the premises including transformation from an agrarian society to an industrial society, authoritarianism and centrally controlled institutions, and exteremely small portions of private investments for science and thechonology R & D of the total. Recently, however, the premises of Korean government S&T development management system have rapidly changed. the characteristics of these changes are including tranformation from an industrial society to a knowledge and information intensive society, globalization, localization, and relatively large portion of private investments for science and technology R & C of the total. The basis of government reforms in Korea was the realization of the performances and values through the enhancement of national competitive capacity, attainment of lean government, decentralization and autonomy. However, the Korean government has attached a symbolic value of strategic organizations representing strong policy intentions of government for the science and technology based development. Most problems associated with the Korean government S&T development management system have grown worse during 1990s. Many people perceive that considerable part of this problem was generated because the government could not properly adapt itself to new administrative environment and the paradigm shift in its role. First of all, the Korean government S&T development management system as a whole failed to develop an integrated vision under which processes in formulating science and thechology development goals and developing consistent government plans concerning science and technology development are guided. Second, most of the local governments have little organizational capacity and manpowers to handle localized activities to promote science and technology in their regions. Third, the measure to coordinate and set priorities to invest resources for the development of science and technology was not effective. Fourth, the Most has been losing its reputation as the symbol of ideological commitment of the top policy maker to promote science and technology. Various ideas to reform government S&T development management system have been suggested recently. Most frequently cited ideas are as follow : (ⅰ)strengthen the functions of MoST by supplementing the strong incentive and regulatory measures; (ⅱ)create a new Ministry of Education, Science & Technology and Research by merging the Ministry of Education and the MoST; (ⅲ)create a new Ministry of Science & Technology and Industry ; and(ⅳ)create a National Science and Technology Policy Council under the chairmanship of the President. Four alternatives suggested have been widely discussed among the interested parties and they each have merits as well as weaknesses. The first alternative could be seen as an alternative which cannot resolve current conflicts among various ministries concerning priority setting and resource allocation. However, this alternatives can be seen as a way of showing the top policymaker's strong intention to emphasize science and technology based development. Second alternative is giving a strategic to emphasize on the training and supplying qualified manpower to meet knowledge and information intensive future society. This alternative is considered to be consistent with the new administrative paradigm emphasizing lean government and decentralization. However, opponents are worrying about the linkages and cooperative research between university and industry could be weakening. The third alternative has been adopted mostly in nations which have strong basic science research but weak industrial innovation traditions. Main weakness of this alternative for Korea is that Korean science and technology development system has no strong basic science and technology research traditions. The fourth alternative is consistent with new administrative paradigms and government reform bases. However, opponents to this alternative are worried that the intensive development of science and technology because of Korea's low potential research capabilities in science and technology development. Considerning the present Korean socio-economic situation which demands highly qualified human resources and development strategies which emphasizes the accumulations of knowledge-based stocks, I would like to suggest the route of creating a new Ministry of Education, Science & Technology and Research by intergrating education administration functions and science & technology development function into one ministry.