• The Journal of The Korea Institute of Intelligent Transport Systems
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• v.11 no.4
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• pp.104-111
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• 2012

It is advantageous to avoid the handover to cell whose dwell time is short or can be ignored in terms of service continuity and average throughput. This paper proposes the handover scheme that is suitable for vehicle in order to improve the wireless Internet service quality. In the proposed scheme, the handover process continues to be learned before being modeled to Discrete-Time Markov Chain (DTMC). This modeling reduces the handover frequency by preventing the handover to cell that could provide service sufficiently to passenger even when vehicle passed through the cell but there was no need to perform handover. In order to verify the proposed scheme, we observed the average number of handovers, the average RSSI and the average throughput on various moving paths that vehicle moved in the given urban environment.

• Education of Primary School Mathematics
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• v.22 no.4
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• pp.261-280
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• 2019

This study is a qualitative study on the case of teaching mathematics between parents and children. 12 lesson units were applied to the 5th grade elementary school child for the first semester, 2019. The purpose of this study was to identify conceptual understanding in the area, the types of problems that child felt difficult during the learning and parents' advantages and difficulties in this setting. For this study, video recording and voice recording were collected for each lesson class. The concept of the area was recognized correctly, the awareness of reconstruction became clear, and the concept of partitioning, unit iteration and structuring an array was more clearly rebuilt. He showed difficulty in conversion between units of the area, in displaying height of the shape whose height is displayed outside and drawing type of figure with same area after the value of the area was offered. In the learning situation of parents and children, parents who are researchers have the advantage of being able to customize up to their children and being free from time and cost constraints. There were difficulties in controlling negative emotion toward the child, determining the level of the children, distribution the class time and deciding the degree of intervention. Furthermore, research on parenting and child-to-parent teaching in mathematics is recommended.

• KIPS Transactions on Computer and Communication Systems
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• v.4 no.6
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• pp.185-196
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• 2015

Energy aware server clusters aim to reduce power consumption at maximum while keeping QoS(Quality of Service) compared to energy non-aware server clusters. They adjust the power mode of each server in a fixed or variable time interval to let only the minimum number of servers needed to handle current user requests ON. Previous studies on energy aware server cluster put efforts to reduce power consumption further or to keep QoS, but they do not consider energy efficiency well. In this paper, we propose an energy efficient cluster management based on autonomous learning for energy aware server clusters. Using parameters optimized through autonomous learning, our method adjusts server power mode to achieve maximum performance with respect to power consumption. Our method repeats the following procedure for adjusting the power modes of servers. Firstly, according to the current load and traffic pattern, it classifies current workload pattern type in a predetermined way. Secondly, it searches learning table to check whether learning has been performed for the classified workload pattern type in the past. If yes, it uses the already-stored parameters. Otherwise, it performs learning for the classified workload pattern type to find the best parameters in terms of energy efficiency and stores the optimized parameters. Thirdly, it adjusts server power mode with the parameters. We implemented the proposed method and performed experiments with a cluster of 16 servers using three different kinds of load patterns. Experimental results show that the proposed method is better than the existing methods in terms of energy efficiency: the numbers of good response per unit power consumed in the proposed method are 99.8%, 107.5% and 141.8% of those in the existing static method, 102.0%, 107.0% and 106.8% of those in the existing prediction method for banking load pattern, real load pattern, and virtual load pattern, respectively.

• Proceedings of the Korea Contents Association Conference
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• 2009.05a
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• pp.59-65
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• 2009

An Edutainment Contents help the learners to recognize the problems effectively, grasp and classify important information needed to solve the problems and convey the contents of what they have learned. Owing not only to this game-like fun but also to the educational effect, The Edutainment contents can be usefully applied to education and training in the areas of scientific technology and industrial technology. This study proposes the Edutainment that users can apply to biotechnology by using intuitive multi-modal interfaces. In this study, a stereoscopic monitor is used to make three dimensional molecular structures, and multi-modal interface is used to efficiently control. Based on the system, this study easily solved the docking simulation function, which is one of the important experiments, by applying these game factors. For this, we suggested the level-up concept as a game factor that depends on numbers of objects and users.

• Journal of Korea Game Society
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• v.9 no.1
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• pp.93-103
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• 2009

A Serious Game helps the learners to recognize the problems effectively, grasp and classify important information needed to solve the problems and convey the contents of what they have learned. Owing not only to this game-like fun but also to the educational effect, The Serious Game can be usefully applied to education and training in the areas of scientific technology and industrial technology. This study proposes the Serious Game that users can apply to biotechnology by using intuitive multi-modal interfaces. In this study, a stereoscopic monitor is used to make three dimensional molecular structures, and multi-modal interface is used to efficiently control. Based on a such system, this study easily solved the docking simulation function, which is one of the important experiments, by applying these game factors. For this, we suggested the level-up concept as a game factor that depends on numbers of objects and users. The proposed system was evaluated in performance comparison in result time of a new drug design process on AIDS virus with previous approach.