• The Transactions of the Korean Institute of Electrical Engineers P
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• v.63 no.4
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• pp.248-253
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• 2014

Generally, power factor correction (PFC) techniques play an important role in the power supply technology. Many new circuit topologies and control strategies for PFC have been proposed. Among them, the brideless PFC (BPFC) reduces the number of switching devices and the losses and improves the power density as well. Moreover, by implementing the improved topology in the discontinous conduction mode (DCM) it ensures almost unity power factor in a simple and effective manner. In the DCM operation gives additional advantages such as zero-current turn-on in the power switches, zero-current turn-off in the output diode and reduces the complexity of the control circuitry. In this paper, a new control strategy for the BPFC is proposed. Also, the performance of the proposed system is demonstrated through experiments.

• Journal of Korea Technical Association of The Pulp and Paper Industry
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• v.39 no.1 s.119
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• pp.8-15
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• 2007

In an effort to develop control strategies for the wet-end of paper machines, dynamic models for retention and formation processes have been developed. The retention process, including headbox total and filler consistencies, white water total and filler consistencies, the basis weight and the ash content of paper, can be modeled from first-principles (mass balances). To include the effect of wet-end chemistry variables, first-pass retention was included as a parameter dependent on operating conditions. In addition, dynamics of formation was simulated by developing an empirical model of formation and coupling with the dynamic models for the retention process. A series of experiments were performed using a pilot paper machine. The experimental results and the model predictions showed relatively good agreement.

• Educational Technology International
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• v.9 no.2
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• pp.123-142
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• 2008

The purpose of this study was to examine how computer conferencing might facilitate collaborative learning for students to engage in meaningful discussion. The participants in this study consisted of the instructor and the students in a graduate level course. Different sources of evidence were used to triangulate the data: in-depth interviews, content analysis of transcripts of discussion, and other archival data including course syllabus, presentation materials, and lecture notes. Participants perceived web-based learning as collaborative process, providing opportunities to share the idea, respect and evaluate different perspectives, and co-construct new insights. Analysis of the data revealed several challenges related collaboration in a web-based learning environment: absence of a sense of community, technical problems, adaptability to different types of learner, and managing the discussion. The data also indicated that a variety of strategies were used to facilitate learning: building a sense of community, technical support, developing instructional methodologies, class size, and design of the content.

• The Journal of Asian Finance, Economics and Business
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• v.6 no.4
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• pp.281-286
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• 2019

The study aims to analyze the adaptation strategies and resilience of tobacco farmers to face unfavorable trading system. The research method refers to a qualitative approach with phenomenological models and case studies. The findings revealed tobacco farmers in Jember developed various adaptation strategies and resilience through farmer group organizations, partnerships, self-capacity building and access to financial institutions based on economic, social, cultural, and experience values from various sources and interactions among fellow tobacco farmers. The tobacco trading system, which is left to the market mechanism, results in low bargaining power of farmers, this encourages tobacco farmers to develop various adaptation and survival strategies, namely through collective activities of farmer groups, partnerships and self-development and access to financial institutions. Dealing with the unfavorable tobacco trading system, tobacco farmers do not switch to other commodity farming but adapt and make Jember a center for tobacco production in East Java and Indonesia. From this findings, it suggests to the government as the regulator does not only provide subsidies for tobacco farmers, but also must provide various technical assistance to increase the ability of tobacco farmers. More importantly, regulations must be made benefit tobacco farmers other than corporations so that equality can be enjoyed by tobacco economy players.

• Journal of the Institute of Electronics and Information Engineers
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• v.51 no.2
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• pp.3-9
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• 2014

We propose energy efficient transmit and receive strategies for nomadic M2M devices. Recently, communication applications consume more and more battery. Hence, the efficient battery management is becoming increasingly important. Turbo code as a channel coding is being widely used in many communication areas. Accordingly, the efficient energy management in using turbo code is an important issue. In this paper, we optimize joint transmit and receive energy for M2M devices pair. We first model the transmit energy and receive energy. Then, we develop the energy efficient transmit and receive strategies.

• Journal of Distribution Science
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• v.13 no.10
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• pp.23-34
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• 2015

Purpose - Currently, the foreign trade environment in China has shifted to a very different system. Korean enterprises have been forced to compete with Chinese enterprises in today's world market owing to the economic growth and technical improvement in China. Research design, data, and methodology - The author visited Korean export enterprises in Shanghai from January 5 to 12, 2014 to implement a questionnaire survey and conduct in-depth interviews with the local enterprises. The author investigated the Shenyang area using e-mail communication. For the questionnaire, one copy of the questionnaire was given to each business and to a staff member for each of the products when a company sold multiple products. Results - Selling cost advantage, efficiency of economic scale, and product differentiation had the most influence on Korean enterprises' export strategy to China. Additionally, entry barrier, product differentiation, and concentration all had an influence on Korean enterprise export strategy to China as well. Conclusion - Korean enterprises developed strategies for price priority, economies of scale, and product differentiation based on changes in the competitive structure in the Chinese market.

• Korean Journal of Organic Agriculture
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• v.11 no.4
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• pp.15-37
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• 2003

Recently, production-consumption quantity and market size of environment-friendly agricultural products(EFAP) have been increased. Consumers have demanded food safety and nutrition of EFAP, but in the near future they will need many kinds of item, relatively low price and high quality. So producers have to make an effort for down-cost, increasing items and developing technical know-how, which can be attained by producer/region organization. Correlation coefficient between the recognition degree for certification system and purchasing amounts at a time is higher than other ones. Therefore public information works using the TV and newspaper must be promoted all the more about certification system. And if the consumer’s satisfaction level of EFAP purchased gets higher, the quantity demanded will be increased more. And consumer’s trust on EFAP is derived from certification system or close relation between producers and consumers. Thus the most important thing of marketing strategies for EFAP is continuously to focus on explanation and information works on certification system by region in metropolitan area. Also, it necessary to introduce green marketing principles and apply to strategies item type. Namely those need to establish target market segmentation And marketing strategy stages according to the green degrees of market And commodity.

• THE INTERNATIONAL COMMERCE & LAW REVIEW
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• v.29
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• pp.121-142
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• 2006

With the advent of Ubiquitous era, Korean government understood its strategic importance and formulated 'IT839 Strategies' with various action plans not to miss the great opportunities which it may allow and eventually to realize u-Korea. As a result, m-Commerce is actualized and new types of Ubiquitous services such as digital multimedia broadcasting(DMB) and wireless broadband Internet(WiBro) are now on their commercial stages. Digital contents are the key success factors of these new services. Digital contents industry is regarded as next generation of growth engine in the digital economy, because it is knowledge-based and high value-added global industry affecting positively on the whole private and public sectors. This paper reviewed the characteristics, business models, technical and market trend of digital contents to be compatible with Ubiquitous environment. Also, it reviewed the development strategies of DMB and WiBro services, which are newly introduced and commercialized in Korea to make it as world leader in these fields. It may be concluded that Korea should make more efforts to development market-oriented digital contents for Ubiquitous era and to realize the sustained economic growth.

• Journal of the Korean Society for Library and Information Science
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• v.21
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• pp.169-190
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• 1991

The purpose of this study is to investigate aspects of office information systems in japanese corporations in order to understand introduction strategies and to find out whether strategy elements could be transferred to Germany. In this study, three points of view played an important role. (a) Technological and infrastructural support systems What kind of role did the liberalization of telecommunication markets and the avaliability of computer hardware play to help develope of database industry and implement office information systems? (b) Strategies and forms of the implementation of office information system: Which strategies were successful, distribution or centralization? How were technical and organizational problems handled? (c) Process of data communication : How did the implementation of office information system change the data communication with in-house or commercial database systems? To answer these questions, this study centered around a two-step field research in Japan. (1) Screening stage: to gain a general overview of office information system in Japan. The results of this initial research have been analysed and carefully evaluated to prepare for the second and major part of field research in Japan. (2) Data collection stage: interviews with respective managers, heads offices, and data processing units in 20 enterprises. The major results of this study are as follows. Today in Japan, office information system is understood as the interconnection of the in-house and commercial database for the maximization of the use of information resource In an organization. In particular, developments in the direction of distributed systems and the 'intelligent office' by means of the new information and communication technologies are very important.

• Journal of Engineering Education Research
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• v.13 no.4
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• pp.70-76
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• 2010

This paper tries the systematic approach to risk which is a major theme in engineering ethics utilizing science and technology studies. The types of risk can be classified as technical risk, methodological risk, epistemological risk by the degree of uncertainty. The strategies for risk management can be assorted to applied science strategy, professional consultancy strategy, post-normal science strategy. These types and strategies of risk request different kinds of expertise such as technocratic expertise, interactive expertise, democratic expertise. This paper can not only contribute to complement and extend engineering ethics education but also be linked with the goals of engineering education in general.