• Journal of the Korea Society for Simulation
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• v.9 no.3
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• pp.1-11
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• 2000

This paper proposes the practical echo-signal synthesis models - UTAHID (Underwater TArget by Highlight Distribution) & M-UTAHID(Modified UTAHID) - of underwater target for active sonar engineering At high frequencies all the echo components that are the specular reflected waves and various elastic scattering wave scan be regarded the summation of individual echo from some equivalent scattering centers, so the underwater target is characterized by highlights distributed in spatial target structure. Proposed models are compared with characteristics of random distributed model & equivalent interval highlight model, and analyzed target strength, echo-elongation effect, target time spread loss and so on. Thus these can be efficiently used in various real systems related to underwater target echo-signal synthesis on active sonar and acoustic countermeasure.

• Proceedings of the Korean Institute of Information and Commucation Sciences Conference
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• 2017.05a
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• pp.551-554
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• 2017

The largest industry in the world is the medical industry, and due to aging and growing demand for well-being, it is necessary to review the competition strategy of the healthcare industry. We will secure competitiveness among medical institutions through the rapid dissemination of ICT convergence, study the intelligence level of digital health care by increasing the capacity of intelligent medical care by combining big data of medical data and artificial intelligence, And to find a countermeasure for constructing a medical optimization model.

• Proceedings of the KIEE Conference
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• 2003.07a
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• pp.131-133
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• 2003

Voltage instability has been studied for some decade now. But, there is not generally accepted definition of voltage instability because of the complex phenomenon and the variety of ways in which it can manifest itself. Both IEEE and CIGRE have the respective definitions. The areas of voltage instability research arc the analysis, simulation and countermeasure of voltage instability. In this paper, we perform a dynamic simulation of voltage instability and voltage collapse using EMTP MODELS. The exponential load model is designed with MODELS and this load model is connected with test power system. The result shows the process of voltage change in time domain when the voltage instability or voltage collapse occurs.

• Proceedings of the Korean Institute of Building Construction Conference
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• 2004.05a
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• pp.101-104
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• 2004

If predicting of compressive strength of construction in construction field at early age is possibile, rational strength management & schedule plan is possible. With method for predicting strength of concrete, many researchers have been making study of maturity method. On the other hand, nowadays rationalization of construction capacity and reduction of a term of works due to improvement of construction capacity and application of a new method of construction is gathering strength with important issue. In accordance with this present condition, construction is being progressed in winter, but proper construction mothed and countermeasure for strength management is not established in case of winter construction. Therefore to investigate application in construction field at winter of strength prediction model that developed at former study, this study aim to measure application of developed strength prediction model through manufacture of mock-up concrete according to kind of strength level at 5$^{\circ}C$.

• Proceedings of the Korean Institute of Navigation and Port Research Conference
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• 2015.07a
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• pp.259-261
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• 2015

The model for ship maneuvering simulation is to enhance the competence of officer's ship maneuvering skills such as navigation equipment operation, collision avoidances, countermeasure an emergency situation so on. Despite using such ship maneuvering model, critical maritime accidents are occurred periodically in the world. To find adequate simulation model to evaluate competence abilities of deck officer who have maneuvering skills with some competence levels, we search the standard ship maneuvering method representing on the part 3 Person Overboard(POB) to onboard emergences of IAMSAR manual. Moreover we monitor the officer's human factors appearing during education and training and consider the use of human factors as fundamental data.

• The Transactions of the Korean Institute of Electrical Engineers A
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• v.52 no.6
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• pp.295-300
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• 2003

Voltage instability has been studied for some decade now. But, There is not generally accepted definition of voltage instability because of the complex phenomenon and the variety of ways in which it can manifest itself. Both IEEE and CIGRE have the respective definitions. The areas of voltage instability research are the analysis, simulation and countermeasure of voltage instability. It needs to model the components of the power system to simulate the voltage instability and voltage collapse. At the beginning, the static simulation was used. This method provides the voltage stability indices and it requires less CPU resource and gives much insight into the voltage and power problem. However, it is less accurate than the dynamic simulation peformed in the time domain simulation. So, when it appears difficult to secure the voltage stability margin in a static stability, it is necessary to perform the dynamic simulation. To perform time-domain simulation, we have to model the dynamic component of the power system like a generator and a load. The dynamic simulation provides the accurate result of the voltage instability. But, it is not able to provide the sensitivity information or the degree of stability and it is time consuming and it needs much CPU resource. In this Paper, we perform a dynamic simulation of voltage instability and voltage collapse using EMTP MODELS. The exponential load model is designed with MODEIS and this load model is connected with test power system. The result shows the process of voltage change in time domain when the voltage instability or voltage collapse occurs.

• International Journal of Fuzzy Logic and Intelligent Systems
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• v.2 no.1
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• pp.53-58
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• 2002

In the construction of successful fuzzy models for nonlinear systems, the identification of an optimal fuzzy model system is an important and difficult problem. Traditionally, sGA(simple genetic algorithm) has been used to identify structures and parameters of fuzzy model because it has the ability to search the optimal solution somewhat globally. But SGA optimization process may be the reason of the premature local convergence when the appearance of the superior individual at the population evolution. Therefore, in this paper we propose a new method that can yield a successful fuzzy model using VmGA(virus messy genetic algorithms). The proposed method not only can be the countermeasure of premature convergence through the local information changed in population, but also has more effective and adaptive structure with respect to using changeable length string. In order to demonstrate the superiority and generality of the fuzzy modeling using VmGA, we finally applied the proposed fuzzy modeling methodof a complex nonlinear system.

• Journal of Korean Institute of Industrial Engineers
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• v.35 no.2
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• pp.178-184
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• 2009

The Nuclear Power Plant(NPP) industry in Korea has been making efforts to reduce the human errors which have largely contributed to about 150 nuclear reactor trips since 2001. Recently, the Crew Resource Management(CRM) training has risen as an alternative countermeasure against the nuclear reactor trips caused by human errors. The effectiveness of CRM training in NPP industry, however, has not been proven to be significant yet. In this study a return on investment(ROI) model is developed to measure the effectiveness of CRM training for the operators in Korean NPP. The model consists of mathematical expressions including multiple variables affecting the CRM training impacts and nuclear reactor trips. Implication of the model is discussed further in detail.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 2003.07a
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• pp.212-215
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• 2003

In this paper, a model pole transformer was designed to improve the reliability of pole transformers and its short circuit withstand strength was tested. The failure causes of the pole transformers which had been operated in the field were analyzed and several patterns of the causes were determined. A novel countermeasure was devised to prevent the failures of the pole transformers in advance. A model pole transformer was designed and made in accordance with the given specifications to strengthen the short circuit withstand capability and its characteristic was tested. As a result, the advanced performance of the model pole transformer was confirmed and novel techniques in manufacturing process was suggested. It is considered that all the methods employed in the developing process will be helpful to design and manufacture the pole transformers thus the reliability of pole transformers in distribution lines will be improved.

• Convergence Security Journal
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• v.5 no.2
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• pp.9-17
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• 2005

Recently It's difficult to deal with about variety of attack. And Simple Security management have a problem. It is that they don't develop system measuring their system envoirment and have efficient attack detector, countermeasure organization about large network. Therefore, need model about enterprise management of various security system and intrusion detection of each systems and response. In this paper, improve PBNM structure that manage wide network resources and presented suitable model in intrusion detection and response of security system. Also, designed policy-based enterprise security management system for effective intrusion detection and response by applying presented model to enterprise security management system.