• Journal of the Institute of Electronics Engineers of Korea TC
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• v.46 no.2
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• pp.97-103
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• 2009

Improving TCP performance has long been the focus of many research efforts in 802.11 wireless networks study. Hop count and Round Trip Time (RTT) are the critical sources which serious affect the TCP performance on end to end connection. In this paper, we analytical derived the affection and based on the analysis we propose TCP should Change its Expected Value (TCP-CEV) when hop count and RTT change by setting a reasonable CWND change rate to improve the performance. The proposed scheme is applicable to a wide range of transport protocols using the basic TCP mechanism, and the protocol behavior is analytically tractable. We show that our simple strategy improves TCP performance at least over 12% in a chain topology, 4.9% in a grid topology and improve the TCP convergence.

• Journal of Korean Society of Industrial and Systems Engineering
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• v.40 no.4
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• pp.120-128
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• 2017

More people travel oversea as the economic size of Korea is getting larger and more new jobs are requested to be created by the society. To respond to these trend and request, Incheon International Airport Corporation (IIAC) is about to expand its processing capability with a new terminal; 54 million passengers to 72 million. IIAC is also introducing new strategies such as open innovation (OI) and creating shared value (CSV). With these changes, IIAC faces new challenges of restructuring its business and organization with new ideas. Most organizations including IIAC are becoming more dependent on external resources to keep their competitive advantages under the turbulence of global business environmental changes. Therefore, they focus on the OI paradigm which is reported as a convincing strategy to improve competitiveness in terms of budget and time-to-market. OI is to quickly react to the rapidly changing business environment and is adopted to support startup incubation. In the previous research with IIAC, three major tasks were defined; utilizing the IIAC brand power for external vendors, building a technology road-map, and introducing a collaboration support system. This paper deals with the collaboration system as proposed in the previous research. We focused on the collaboration process for startup incubation. Cases were studied; the K-startup model by the government, a university model to explore youth startups, and a R&D institute model to study professional startups. Based on the case studies, we defined an IIAC model and proposed issues to take care of. The model is distinguished from the other studied models since IIAC is a prospective customer of new technology.

• Journal of Korean Elementary Science Education
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• v.25 no.2
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• pp.167-178
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• 2006

The purpose of this study was to explore characteristics of sixth grade students' opistemological beliefs in science and the relationship to learner's characteristics: learning motivation, learning strategies, and logical thinking. The subjects were 265 sixth graders and data was collected through two types of questionnaires, translated and modified by researchers: opistemological beliefs regarding science, learning motivation & strategies. The results of this study were as follows. The students believed that the goals of science were related to activations such as 'Science is experiment', or 'Science is invention: These beliefs were connected with the emphasis of science classes or the focus of the science curriculum. However, the students' beliefs related to the changeability of science knowledge, the source of science knowledge, and the role of experiments in developing knowledge were oriented to modern opistemological views. Moreover, the beliefs were meaningfully related to students' characteristics: learning motivation, learning strategies, and logical thinking. Among the students' characteristics, logical thinking was especially related to all of the factors of students' beliefs: the changeability of science knowledge, the source of science knowledge, and the role of experiments in developing knowledge. However, the students who believed that scientific knowledge came from scientists, science teachers, or science textbooks had high levels of self-efficacy. Therefore, the belief that scientific knowledge is formed by self-discovery, in order to generate high self-efficacy, needs to be encouraged. From the results, it is possible to check the orientation of current science education based on the students' opistemological beliefs. In addition, the resources can be accumulated for persevering in our efforts to achieve a positive orientation for science education.

• Journal of the Economic Geographical Society of Korea
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• v.19 no.2
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• pp.313-329
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• 2016

The paper shows that Uganda lacks an adequate institutional framework to achieve agriculture modernization. Based on constellation model, the paper proposes an effective way to promote agricultural development through policy and institutional partnerships at various levels of governance and action by various stakeholders in the sector. From this theoretical perspective, the paper raises salient research questions: Why is Abim District an important focus for Agricultural development? What is the effect of institutional arrangements and partnerships in agriculture development in Abim District? What forms of institutional partnerships and collaboration framework can effectively address the challenge in the District and Northern Uganda as a whole? These concerns are important obstacles to improved agricultural performance in Uganda as dysfunctional institutional arrangements and norms are majorconstraints to agricultural development. The findings demonstrate that institutional gaps, bureaucracy, institutional proliferation and overlapping roles have derailed agriculture modernization. Hence, the development strategy proposes creating and rejuvenating all essential players operating in the region, developing or deepening their inter-linkages through judicious and sustainable partnerships with all the principal players in Abim District.

• The Transactions of The Korean Institute of Electrical Engineers
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• v.65 no.5
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• pp.730-737
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• 2016

Electric utilities may face new threats with increase in electric vehicles (EVs) in the personal automobile market. The peak demand will increase which may stress the distribution network equipment. The focus of this paper is on an adaptive control of smart household appliances by using an intelligent load management system (ILMS). The main objectives are to accomplish consumer needs and prevent overloading of power grid. The stress from the network is released by limiting the peak demand of a house when it exceeds a certain point. In the proposed strategy, for each smart appliance, the customers will set its order/rank according to their own preferences and then system will control the household loads intelligently for consumer reliability. The load order can be changed at any time by the customer. The difference between the set and actual value for each load's specific parameter will help the utility to estimate the acceptance of this intelligent load management system by the customers.

• Journal of Information Technology Applications and Management
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• v.27 no.4
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• pp.85-91
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• 2020

Animation is a field of popular visual art that is established in human life, and the form of characters appearing is an important factor that is highly anticipated by the public. Designing animation characters according to aesthetic characteristics not only satisfies people's aesthetic needs but can also increase their artistic immersion in animation works. In addition, animation storytelling is delivered around characters and enhances the value of the work by encouraging more public to focus on it. In this paper, we tried to analyze the design elements of Minions characters to derive the reason why they are loved by the public. Among the morphological characteristics of bicepsin characters, a study was conducted on the fact that bicepsin characters visually express 'cute' through the study of infantile eating and color. The visual cuteness elements of a bisung character will soon be linked to the psychological satisfaction of the audience's work and will be a factor in the appreciation of the value of the work. By studying the elements of expression that represent isosin characters, I would like to discuss the factors that help the audience to immerse and get satisfaction with the characters. This will be used as an important factor for an animation character to have for the audience and will reveal its value. Second-class animation images belong to the art of small pieces, suitable for all the audience to enjoy. The two-size animated image has a strong appeal and entertainment, is a confusing visual attribute, can stimulate the audience's five senses. Compared with the actors in the movie, the visual form of the animation is more important.

• Journal of Digital Contents Society
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• v.13 no.2
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• pp.159-167
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• 2012

Eye tracking technology tracks human eyes movements to understand user's intention. This technology has been improving slowly and should be used for a variety of occasions now. For example, it enables persons with disabilities to operate a computer with their eyes. This article will show a typical implementation of an eye tracking system for persons with disabilities, after introducing the design principles and specific implementation details of an eye tracking system. The article discussed the realization of self-adapting regulation algorithm in detail. The self-adapting algorithm is based on feedback signal controlling the lens movements to realize automatic focus, and to get a clear eyes image. This CCD camera automatic focusing method has self-adapting capacity for changes of light intensity on the external environment. It also avoids the trouble of manual adjustment and improves the accuracy of the adjustment.

• Journal of the East Asian Society of Dietary Life
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• v.18 no.5
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• pp.849-860
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• 2008

The principal objective of this study was to assess the behavior of customers who visit hotel buffet restaurants. This information will provide us with a good marketing strategy, allowing us to control for different customer characteristics and focus on giving marketers useful clues that make it easy to understand the selective attributes for hotel buffet restaurants. Thus, the application of selective attributes is predicated on the results of the analysis. Additionally, this survey was completed by regular customers. The following are the concrete results of the study. First of all, customer's behaviors differ radically with the selective attributes of hotel buffet restaurants. The most crucial factors were found to be "quality of food", "hygiene & cleanliness", and "service". These factors have nothing to do with customer characteristics & demographic features. "Opinions of their relatives, colleagues" and "experience of restaurants" are all sources that substantially influence the selective attributes of restaurants and this is the only way to survive the ever-changing market situation. Finally, hotel buffet restaurants generally attempt to lure customers with healthy food, special corners, fresh vegetables, and fresh sashimi, as compared to the services provided by hotel outlets. According to upgrade service quality & restaurant interior, also, buffet restaurants tend to provide guests with a more charming. Food service companies should consider the question "what really is service?" and thus seek to provide a variety of events. Preparing for unforeseeable market situations, we should execute efficient marketing strategies in order to assure continued customer satisfaction.

• Korean Medical Education Review
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• v.16 no.3
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• pp.126-131
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• 2014

The purpose of this study is to analyze the medical education system of Korea and to propose a method of curriculum redesign. Although there have been many attempts by medical educators to improve the quality of medical education, the results have not been fruitful. First, there exists a limitation to the dualistic curriculum design based on Flexnerianism, and thus, this model does not provide an integrated experience to medical students. Therefore, we propose a unidimensional model for curriculum redesign. Second, it is impossible to promote excellence in medical education without solving the structural problems of teaching and learning, such as the teaching competency of the faculty, large-scale lectures, and team teaching systems. A curricular strategy that emphasizes mutual interaction and teaching accountability is necessary to promote meaningful learning. Third, the current clinical training system, the circulation model, provides incomplete training as well as a lack of sequence and articulation experiences. This system needs to be redesigned in a way that allows only those students who have mastered both the knowledge and the application of medical education to advance to the next step. Fourth, norm-referenced assessments of a medical college distort the learning process and create unconstructive system energy. A criterion-referenced assessment that values cooperation, independent study, and intrinsic motivation is more important for the reliability and validity of the assessment. Medical students should not focus on formative and informative learning. Medical colleges should investigate the multifaceted potential of the students and provide transformative learning to grow students into change agents. For this to take place, curriculum redesign-not new methods of medical education-is required.

• Journal of Korean Society of Industrial and Systems Engineering
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• v.38 no.3
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• pp.100-107
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• 2015

Recently as the manufacturers want competitiveness in dynamically changing environment, they are trying a lot of efforts to be efficient with their production systems, which may be achieved by diminishing unplanned operation stops. The operation stops and maintenance cost are known to be significantly decreased by adopting proper maintenance strategy. Therefore, the manufacturers were more getting interested in scheduling of exact maintenance scheduling to keep smooth operation and prevent unexpected stops. In this paper, we proposedan integrated maintenance approach in injection molding manufacturing line. It consists of predictive and preventive maintenance approach. The predictive maintenance uses the statistical process control technique with the real-time data and the preventive maintenance is based on the checking period of machine components or equipment. For the predictive maintenance approach, firstly, we identified components or equipment that are required maintenance, and then machine parameters that are related with the identified components or equipment. Second, we performed regression analysis to select the machine parameters that affect the quality of the manufactured products and are significant to the quality of the products. By this analysis, we can exclude the insignificant parameters from monitoring parameters and focus on the significant parameters. Third, we developed the statistical prediction models for the selected machine parameters. Current models include regression, exponential smoothing and so on. We used these models to decide abnormal patternand to schedule maintenance. Finally, for other components or equipment which is not covered by predictive approach, we adoptedpreventive maintenance approach. To show feasibility we developed an integrated maintenance support system in LabView Watchdog Agent and SQL Server environment and validated our proposed methodology with experimental data.