• Proceedings of the IEEK Conference
• /
• 2008.06a
• /
• pp.629-630
• /
• 2008

MANET is depended on the property as like variable energy, high degree of mobility, location environments of nodes etc. So, in this paper, we propose an algorithm techniques which is TICC (Time Interval Clustering Control) based on energy value in property of each node for solving cluster problem. It provides improving cluster energy efficiency how can being node manage to order each node's energy level. TICC is clustering method. It has shown that Node's energy efficiency and life time are improved in MANET.

• Journal of the Korean Society for Industrial and Applied Mathematics
• /
• v.3 no.2
• /
• pp.121-135
• /
• 1999

This paper studies the problem of inverting minimal path sets to obtain minimal cut sets for complex system. We describe efficiency of inversion algorithm by the use of boolean algebra and we develop inclusion-exclusion algorithm and pivotal decomposition algorithm for reliability calculation of complex system. Several examples are illustrated and the computation speeds between the two algorithms are undertaken.

• KSII Transactions on Internet and Information Systems (TIIS)
• /
• v.13 no.1
• /
• pp.133-151
• /
• 2019

In order to achieve faster content distribution speed and stronger fault tolerance, a P2P peer can connect to multiple peers in parallel and receive chunks of the data simultaneously. A critical issue in this environment is selecting a set of nodes participating in swarming sessions. Previous related researches only focus on performance metrics, such as downloading time or the round-trip time, but in this paper, we consider a new performance metric which is closely related to the network and propose a peer selection algorithm that produces the set of peers generating optimal worst link stress. We prove that the optimal algorithm is practicable and has the advantages with the experiments on PlanetLab. The algorithm optimizes the congestion level of the bottleneck link. It means the algorithm can maximize the affordable throughput. Second, the network load is well balanced. A balanced network improves the utilization of resources and leads to the fast content distribution. We also notice that if every client follows our algorithm in selecting peers, the probability is high that all sessions could benefit. We expect that the algorithm in this paper can be used complementary to existing methods to derive new and valuable insights in peer-to-peer networking.

• Journal of the Korea Computer Industry Society
• /
• v.9 no.5
• /
• pp.197-206
• /
• 2008

Gifted education has drawn much attention in education in recent years and gifted education in computers in elementary education has been emerged as well throughout the country. Now computer algorithm education is considered as a core subject in the area because computer algorithm is the essence of computer technology on which information society relies technically, and also it provides theoretical basis for problem solving using computers. And we observe that fostering learner's creativity is crucial in learning computer algorithms because problem solving requires creativity in general. In the paper, we discuss the procedure to foster learner's creative problem solving ability which would greatly help students learn computer algorithms, and then we discuss how we can make algorithmic ideas into reality. Furthermore, we note that an appropriate level education is necessary for better results for outstanding students in the program, and lastly we propose ideas to improve current gifted elementary education in computers. The content of the paper is largely originated from experiences of teaching gifted elementary students conducted by a local university and sponsored by its municipal government for six years.

• 한국정보교육학회:학술대회논문집
• /
• 2010.08a
• /
• pp.271-280
• /
• 2010

Education focus on cultivating creative talent in the rapidly changing knowledge and Information society. Algorithms of computer science students to logical thinking and problem solving to find the best solution is an effective learning content. But the algorithm often educate at the University of reality when considering the level of elementary school students' cognitive structure and it is very important for teaching. In this study, based on the principle of the algorithm with an educational content for students to understand the principles of their own problems as the best way to resolve the situation with the ability to want to kidney. Content that contains elements of the game interesting for students to participate actively interested in effective teaching methods to the understanding of the principles of the algorithm will be a big help.

• The Journal of Korean Association of Computer Education
• /
• v.15 no.3
• /
• pp.1-10
• /
• 2012

The flow of computer education in modern knowledge and information society contains the computer science courses to cultivate the higher-level thinking abilities such as logical thinking skills, creativity, and problem-solving ability of learners. The purpose of this study is to recognize the need to promote the algorithmic thinking power to improve the problem solving ability of learners, to design the algorithm class based on the anchored instruction strategy for elementary school students and to verify the effectiveness. Anchored instruction model and cases are added to the class. Elementary school students were subjects and divided into a control group in which the traditional algorithm teaching method was conducted and an experimental group in which algorithm class was conducted applying anchored instruction. As results, an experimental group has shown improvements on problem solving compared to a control group.

• Journal of the Korea Academia-Industrial cooperation Society
• /
• v.16 no.5
• /
• pp.3391-3398
• /
• 2015

Recently, the large scaled lead-acid battery is widely introduced to efficient operation of the photovoltaic system in many islands. but the demand of lithium-ion battery is getting increased by the operation of wind power and replacement of the lead-acid battery. And also, under the renewable portfolio standard(RPS) and energy efficiency resource standard(EERS) policy of Korea government, the introduction of energy storage system(ESS) has been actively increased. Therefore, this paper presents the operation algorithm of hybrid battery management system(BMS) using the lead-acid and lithium-ion batteries, in order to maximize advantage of each battery. In other words, this paper proposed the algorithm of state of charge(SOC) and hybrid operation algorithm to calculate the optimal composition rate considering the fixed cost and operation cost of each battery. From the simulation results, it is confirmed that the proposed algorithms are an effective tool to evaluate SOC and to optimally operate hybrid ESS.

• Proceedings of the Korean Institute of Information and Commucation Sciences Conference
• /
• 2012.05a
• /
• pp.612-615
• /
• 2012

Energy efficiency in wireless sensor network is a principal issue because wireless sensor network uses limited energy. In wireless sensor network, because nodes are placed randomly, they may be concentrated in certain area. This dense area causes shortening the life of the concentrated area, and furthermore reducing the life of the entire network. In this paper, we suggest a additional cluster head selection algorithm for reducing the overload of head node in dense area and shows simulation result using our algorithm with LEACH algorithm.

• KSII Transactions on Internet and Information Systems (TIIS)
• /
• v.7 no.6
• /
• pp.1379-1397
• /
• 2013

We consider a system where a licensed radio spectrum is shared by multiple primary users(PUs) and secondary users(SUs). As the spectrum of interest is licensed to primary network, power and channel allocation must be carried out within the cognitive radio network so that no excessive interference is caused to PUs. For this system, we study the joint beamforming and power allocation problem via game theory in this paper. The problem is formulated as a non-cooperative beamforming and power allocation game, subject to the interference constraints of PUs as well as the peak transmission power constraints of SUs. We design a joint beamforming and power allocation algorithm for maximizing the total throughput of SUs, which is implemented by alternating iteration of minimum mean square error based decision feedback beamforming and a best response based iterative power allocation algorithm. Simulation results show that the algorithm has better performance than an existing algorithm and can converge to a locally optimal sum utility.

• Journal of The Korean Association of Information Education
• /
• v.2 no.2
• /
• pp.252-259
• /
• 1998

Vehicle navigation systems employ a certain route planning algorithm that provides the shortest path between the starting point and the destination point. The performance of a given route planning algorithm is measured through the degree of optimal route selection and the time cost to complete searching an optimal path. In this paper, various route planning algorithms are evaluated through computer simulation based on a real digital map database. Among those algorithms evaluated in this paper, the Modified Bi-directional A${\ast}$ algorithm is found to be the best algorithm for use in vehicle navigation systems.