• KSII Transactions on Internet and Information Systems (TIIS)
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• v.8 no.12
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• pp.4411-4431
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• 2014

Mobile ad hoc networks (MANETs) have recently gained increased interest due to the widespread use of smart mobile devices. Group communication applications, serving for better cooperation between subsets of business members, become more significant in the context of MANETs. Multicast routing mechanisms are very useful communication techniques for such group-oriented applications. This paper deals with multicast routing problems in terms of stability and scalability, using the concept of stable core. We propose LMRSC (Lightweight Multicast Routing Based on Stable Core), a lightweight multicast routing technique for MANETs, in order to avoid periodic flooding of the source messages throughout the network, and to increase the duration of multicast routes. LMRSC establishes and maintains mesh architecture for each multicast group member by dividing the network into several zones, where each zone elects the most stable node as its core. Node residual energy and node velocity are used to calculate the node stability factor. The proposed algorithm is simulated by using NS-2 simulation, and is compared with other multicast routing mechanisms: ODMRP and PUMA. Packet delivery ratio, multicast route lifetime, and control packet overhead are used as performance metrics. These metrics are measured by gradual increase of the node mobility, the number of sources, the group size and the number of groups. The simulation performance results indicate that the proposed algorithm outperforms other mechanisms in terms of routes stability and network density.

• Journal of the Korean Society of Food Culture
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• v.26 no.2
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• pp.120-127
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• 2011

To identify "Gongsik", defined as food-sharing by picking food from a common plate using personal utensils, we conducted 7 focus group interviews including 47 university students during a 6 month period. Focus group discussions were audio taped, transcribed, and categorized into major themes. We divided Gongsik into the following categories: practical reasons, socio-psychological reasons, boundaries, suppressive situations, emotional characteristics, attitudes towards using different utensils, and future prospects. Gongsik appeared to be useful for fostering quick food sharing, intimacy and solidarity, and a fixed behavior learned at home. If the amount of food was too small to provide individual servings, as in Jjigae, Gongsik was likely to occur spontaneously. Family, close relatives, friends, and lovers sharing common activities and/ or blood ties were composed the boundaries of Gongsik. However, Gongsik was avoided in elegant restaurants or in view of foreigners. Participants showed mixed feelings towards Gongsik. Gongsik conducted with a spoon was considered to increase the degree of suggested intimacy in a food sharing context. Half of the students believed that the practice of Gongsik would be maintained into the future. Gongsik is a culturally-specific behavior that includes both positive and negative meanings. Aside from improving understanding of the cultural aspects of food-sharing, we suggest that the negative aspects of Gongsik related to the issue of hygiene be considered in food and nutrition education.

• Nuclear Engineering and Technology
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• v.42 no.4
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• pp.339-364
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• 2010

Following a joint OECD/NEA-IAEA-sponsored meeting to define the current role and future perspectives of the application of Computational Fluid Dynamics (CFD) to nuclear reactor safety problems, three Writing Groups were created, under the auspices of the NEA working group WGAMA, to produce state-of-the-art reports on different aspects of the subject. The work of the second group, WG2, was to document the existing assessment databases for CFD simulation in the context of Nuclear Reactor Safety (NRS) analysis, to gain a measure of the degree of quality and trust in CFD as a numerical analysis tool, and to take initiatives to extend the existing databases. The group worked over the period of 2003-2007 and produced a final state-of-the-art report. The present paper summarises the material gathered during the study, illustrating the points with a few highlights. A total of 22 safety issues were identified for which the application of CFD was considered to potentially bring real benefits in terms of better understanding and increased safety. A list of the existing databases was drawn up and synthesised, both from the nuclear area and from other parallel, non-nuclear, industrial activities. The gaps in the technology base were also identified and discussed. In order to initiate new ways of bringing experimentalists and numerical analysts together, an international workshop -- CFD4NRS (the first in a series) -- was organised, a new blind benchmark activity was set up based on turbulent mixing in T-junctions, and a Wiki-type web portal was created to offer online access to the material put together by the group giving the reader the opportunity to update and extend the contents to keep the information source topical and dynamic.

• Journal of the Korea Society of Computer and Information
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• v.29 no.4
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• pp.31-38
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• 2024

This study proposes hyper-parameter settings for developing a generative AI-based learning support tool to facilitate programming education in online distance learning. We implemented an experimental tool that can set research hyper-parameters according to three different learning contexts, and evaluated the quality of responses from the generative AI using the tool. The experiment with the default hyper-parameter settings of the generative AI was used as the control group, and the experiment with the research hyper-parameters was used as the experimental group. The experiment results showed no significant difference between the two groups in the "Learning Support" context. However, in other two contexts ("Code Generation" and "Comment Generation"), it showed the average evaluation scores of the experimental group were found to be 11.6% points and 23% points higher than those of the control group respectively. Lastly, this study also observed that when the expected influence of response on learning motivation was presented in the 'system content', responses containing emotional support considering learning emotions were generated.

• Korean Journal of Mathematics
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• v.22 no.1
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• pp.45-56
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• 2014

Modern society demands leaders who are trained with competence to not only approach knowledge but also create new knowledge by comprehensively understanding and applying it, and a leader with character and commitment to share one's ideas with others and be able to accept criticisms. In response to these societal changes, universities are increasingly adopting 'small group discussion-based classes with an attempt to develop and strengthen communication skills through reading, writing and speaking. This paper seeks to introduce a case of a math lecture, where discussion-based class was applied to mathematical education, requiring practical problem-solving through an argumentative thought process.

• Journal of Engineering Education Research
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• v.16 no.3
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• pp.79-86
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• 2013

The purpose of this study was to analyze the factors related to the satisfaction of the introductory engineering education program for the employees, who majored liberal arts or commerce, among the educational programs for industrial workers which are performed as an effort to spread the performance of the Innovation Center for Engineering Education, and reinforce the competitiveness through effective program operation. This study was performed on the basis of CIPP evaluation model (context, input, process, product). A factorial analysis and a regression analysis were conducted based on a survey made on 87 persons who completed the introductory engineering education program among the employees of D group who majored liberal arts or commerce. It is expected that this study will contribute toward suggesting the implications for designing and operating the educational programs for industrial workers in order to find out the important factors of satisfaction and to conduct the education operation with professionalism.

• Proceedings of the KIEE Conference
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• 2004.11c
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• pp.426-428
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• 2004

Sensor network supports data delivery from physical world to cyber space Sensors get physical events then wireless network transfers sensor data to service server. We use sensor network technology to manage location information of asset. In ubiquitous computing environment, user localization is basic context for intelligent service. A lot of research group make effort to develop low cost localization technology. In this paper, we propose asset monitoring system using wireless sensor network. It is implemented using ad hoc network technology which can be adopted to smart home and this system can monitor the asset location and movement.

• Proceedings of the KSPS conference
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• 1997.07a
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• pp.81-91
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• 1997

This paper deals with the problems of English listening comprehension: the rate of understanding difference in positions and sentence structures, parts of speech easily missed to understand, English sounds only in English(not in Korean), confusion of sounds, unaccented prefixes and suffixes, polysemy, homonym, juncture, understanding as one word by two different words, and sound blending in a normal speed of connected speech. Bearing those in mind I taught Suwon University freshmen video English with the mixed idea of Peterson's bottom-up and top-down methods putting in a meaningful context with thought group rather than word to word understanding. As a consequence, their errors come: prepositions, conjunctions, unstressed prefixes and suffixes, -ing from the present progressives and so forth. Assignments to have students transcribe the TV commercials and the names of reporters or Korean related news from English broadcastings are of use and help.

• Proceedings of the Korean Institute of Intelligent Systems Conference
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• 1998.06a
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• pp.1-19
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• 1998

In this Kdynote address, two types of information granules are considered : (ⅰ) one for set assignments of a concept descriptor and (ⅱ) the other for truthood assignment to the concept description verifier. The first is, the process which specifies the assignment of an object to a clump, a class, a group, etc., and hence defines the set membership with a relational constraint. the second is the assignment of the degree of truthood or the membership specification of the abstract concept of truthood which specifies the " veristic" constraint associated with the concept descriptor. The combination of these two distinct assignments let us generate four set and logic theories. This then leads to the concern of normal forms and their derivation from truth tables for each of these theories. In this regard, some of the fundamental issues arising in this context are discussed and certain preliminary answers are provided in order to highlight the consequences of these theories.

• Journal of Technology Innovation
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• v.12 no.2
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• pp.227-245
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• 2004

Studies on compensation structures of international technology licensing show that the level of intellectual property protection in the host market and the favorableness of the host country's economic environment are positively related to the use of running royalty-based compensation structure. Lump-sum fee or fixed royalty compensation is more likely to be used in the introduction and decline stages of the technology life cycle, and running royalty compensation in the growth stage. The international experience and the size of the licensor company are positively related to the use of running royalty. In this theoretical context, this paper analyzes the choice of compensation structures in Korean technology imports. The paper uses the officially reported data to analyze the compensation structures. It analyzes the characteristics of the compensation structures in terms of fixed royalty and running royalty by licensor country, group of licensor countries and size of licensee companies.