• Journal of Electrical Engineering and Technology
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• v.1 no.4
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• pp.435-447
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• 2006

This paper presents an application of the parallel Adaptive Evolutionary Algorithm (AEA) to search an optimal solution of the service restoration in electric power distribution systems, which is a discrete optimization problem. The main objective of service restoration is, when a fault or overload occurs, to restore as much load as possible by transferring the de-energized load in the out of service area via network reconfiguration to the appropriate adjacent feeders at minimum operational cost without violating operating constraints. This problem has many constraints and it is very difficult to find the optimal solution because of its numerous local minima. In this investigation, a parallel AEA was developed for the service restoration of the distribution systems. In parallel AEA, a genetic algorithm (GA) and an evolution strategy (ES) in an adaptive manner are used in order to combine the merits of two different evolutionary algorithms: the global search capability of the GA and the local search capability of the ES. In the reproduction procedure, proportions of the population by GA and ES are adaptively modulated according to the fitness. After AEA operations, the best solutions of AEA processors are transferred to the neighboring processors. For parallel computing, a PC cluster system consisting of 8 PCs was developed. Each PC employs the 2 GHz Pentium IV CPU and is connected with others through switch based fast Ethernet. To show the validity of the proposed method, the developed algorithm has been tested with a practical distribution system in Korea. From the simulation results, the proposed method found the optimal service restoration strategy. The obtained results were the same as that of the explicit exhaustive search method. Also, it is found that the proposed algorithm is efficient and robust for service restoration of distribution systems in terms of solution quality, speedup, efficiency, and computation time.

• Journal of the Institute of Convergence Signal Processing
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• v.9 no.4
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• pp.313-320
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• 2008

The dynamic clustering technique has some problems regarding energy consumption. In the cluster configuration aspect the cluster structure must be modified every time the head nodes are re-selected resulting in high energy consumption. Also, there is excessive energy consumption when a cluster head node receives identical data from adjacent cluster sources nodes. This paper proposes a solution to the problems described above from the energy efficiency perspective. The round-robin cluster header(RRCH) technique, which fixes the initially structured cluster and sequentially selects duster head nodes, is suggested for solving the energy consumption problem regarding repetitive cluster construction. Furthermore, the issue of redundant data occurring at the cluster head node is dealt with by broadcasting metadata of the initially received data to prevent reception by a sensor node with identical data. A simulation experiment was performed to verify the validity of the proposed approach. The results of the simulation experiments were compared with the performances of two of the must widely used conventional techniques, the LEACH(Low Energy Adaptive Clustering Hierarchy) and HEED(Hybrid, Energy Efficient Distributed Clustering) algorithms, based on energy consumption, remaining energy for each node and uniform distribution. The evaluation confirmed that in terms of energy consumption, the technique proposed in this paper was 29.3% and 21.2% more efficient than LEACH and HEED, respectively.

• Proceedings of the KIEE Conference
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• 1991.07a
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• pp.781-786
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• 1991

This paper introduces a new methodology for multisensor data fusion. The method makes use of fuzzy techniques and possibility distribution as a fuzzy restriction which acts as an elastic constraint on the values that may be assigned to a variable. We propose a simple sensor fuzzy modeling method which can be used for cluster validity analysis. As a result, the feasibility of these multisensor data fusion modules is demonstrated by computer simulation applicable to the problem of object identification.

• Journal of Fisheries and Marine Sciences Education
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• v.29 no.1
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• pp.169-179
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• 2017

The purpose of this research is to identify the overall operation status of the marine program, which operates in the Department attempted, in various qualities and operational programs consisting of lecturers derives the problem, and to the policy proposal accordingly. In order to complete the purpose, to analyzed based on the status of marine programs of the Marine Training Center Chungcheong Cluster of three Education Offices from 2014 until the first half of 2016. In addition to direct visit the scene to confirm the status of the data collected through field surveys and interviews were officials confirm the validity of the data, and also to obtain additional study. In conclusion, First, Establish measures for the reduction of blind spots urgent law. Second, Appliances installed for program development and Instructors training.

• Transactions of Materials Processing
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• v.26 no.4
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• pp.234-239
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• 2017

A general approach is proposed for 3-D coupled FE analysis of the deformation of the strip and rolls in flat rolling. FE formulation, schemes for the treatment of contact occurring in a cluster of deforming objects, and the solution strategy are described in detail. The validity of the approach is examined through comparison with observed measurements. The approach is applied to the analysis of deformation in a four-high and six-high mill.

• Proceedings of the Korean Institute of Intelligent Systems Conference
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• 1995.10b
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• pp.40-44
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• 1995

In this paper, we propose a retrieval system using knowledges of database expressed linguistically, where the relation between data are constructed by FCM. Several algorithms have been proposed to solve the major problem in the conventional retrieval system that the system doesn't reply in case of no data equal to user's query, and to express knowledge of database linguistically. This paper proposes the improved method of adding new cluster and the method of retrieving database from user's query. The validity of this retrieval system is shown by applying its algorithm to an example : the mail order service in post office.

• Journal of Korean Academy of Nursing
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• v.21 no.2
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• pp.230-246
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• 1991

Pain is a subjective and multidemensional concept. Therefore the patient's expression of pain have been referedl to the best believable indicator of pain condition but the support data obtained from the patient considered cultural difference is a deficient condition in determinded on the precise nursing diagnosis. The purpose of this reasearch was to understand multiple pain reponses in cultural difference and sensitivity, to encourage communication between medical teams, and to provide the foundation data of on data of precise nursing assessment for the patient in pain. The research problem was to grasp pain express pattern of Korean peptic ulcer patients. The subjects were 20 peptic ulcer patients in medical unit or OPD of twp university hospitals in Seoul. Data were collected from September 7th to 22nd, 1990 by intensive interviews. Interviews were done by the researcher and all were tape - recorded. The Data analysis was done by Phenomenological method from Van Kaam. Validity assured by confirmation of the internal consistency of the statements and catigory by nursing collegue in educational and clinicions in medical care. From the emic data, 96 descriptive statements were organized in 18 theme cluster. The results of study were summerized as follows. 1. Pain Express Pattern cluster of Peptic Ulcer Patients were “Pain as clogging”, “shallow pain”, “pain as pressing”, “nauseating pain”, “pain as smarting”, “pain as pulling”, “pain as pricking”, “pain as bursting”, “wrenching pain”, “excising pain”, “uncontrollable pain for mind and body”, “awakening pain”, “pain as hollowing” and the other cluster. As above mentioned, Pain Express Pattern of Peptic Ulcer Patient appeared diversely in verbal and they were propered to Korean culture. Therefore they will provide for the foundation data of precise nursing assessment.

• Journal of Gifted/Talented Education
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• v.24 no.4
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• pp.509-541
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• 2014

There was a great need to consider a core competency-based approach as a new direction of the science education for gifted students according to the value and vision of the 21st century knowledge-based societies. Therefore we developed a core competency model of scientist and examined its validity as a prerequisite for a core competency-based education of science gifted students. In order to this, the survey was conducted after developing questionnaire through the theoretical review of the various resources such as paper, book, and newspaper articles and the qualitative analysis of the behavioral event interview, and then an exploratory factor analysis was performed to validate the factor structure based on the results of the survey. The results revealed that the core competency model with the 5 cluster units of competency and the 15 core competencies was potentially constituted. And the reliability, convergent validity, and discriminant validity of the core competency model were verified through the confirmatory factor analysis. The cognitive cluster consisted of 5 competencies and they were as follows: creative, comprehensive, exploratory, analytical, and conceptual thinking competency. The achievement-orientation cluster consisted of 3 competencies and they were as follows: initiative, preparation & problem solving, and strategic influence competency. The scientific attitude cluster consisted of 3 competencies and they were as follows: flexible thinking & attitude, passion for research, and views about science competency. The personal effectiveness cluster consisted of 2 competencies and they were as follows: diverse experiences and global attitude competency. Finally, the networking cluster consisted of 2 competencies and they were as follows: personal understanding and communication competency. Findings were expected to provide the basic data for developing programs and establishing strategies based on the core competency as well as introducing the core competency model of scientist to science education for gifted students effectively.

• Journal of Advanced Navigation Technology
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• v.27 no.2
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• pp.167-172
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• 2023

The P-3C maritime patrol aircraft operated by the Republic of Korea Navy is equipped with various sensor devices (LRUs, line replace units) for tactical data collection. Depending on the characteristics of the sensor device, it operates with various communication protocols such as IEEE 802.3, MIL-STD-1553A/B, and ARINC-429. In addition, the collected tactical data is processed in the tactical station for mission operators, and this tactical station constitutes a clustering network on Gigabit Ethernet and operates in a distributed processing method. For communication with the sensor device, a specific tactical station mounts a peripheral device (eg. ARINC-429 interface card). The problem is that the performance of the entire distributed processing according to the peripheral device control and communication relay of this specific device is degraded, and even the operation stop of the tactical station has a problem of disconnecting the communication with the related sensor device. In this paper, we propose a method to mount a separate gateway to solve this problem, and the validity of the proposed application is demonstrated through the operation result of this gateway.

• Journal of the Korea Society for Simulation
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• v.19 no.4
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• pp.99-109
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• 2010

Existing research about automated wafer transport management strategy for semiconductor manufacturing equipment was mainly focused on dispatching rules which is optimized to specific system layout, process environment or transfer patterns. But these methods can cause problem as like requiring additional rules or changing whole transport management strategy when applied to new type of process or system. In addition, a lack of consideration for interconnectedness of the added rules can cause unexpected deadlock. In this study, in order to improve these problems, propose dynamic priority based transfer job decision making algorithm which is applicable with regardless of system lay out and transfer patterns. Also, extra rule handling part proposed to support special transfer requirement which is available without damage to generality for maintaining a consistent scheduling policies and minimize loss of stability due to expansion and lead to improve productivity at the same time. Simulation environment of Twin-slot type semiconductor equipment was built In order to measure performance and examine validity about proposed wafer scheduling algorithm.