• Journal of Satellite, Information and Communications
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• v.6 no.2
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• pp.20-25
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• 2011

The authors have proposed novel TDD-CDMA systems with Pre-Rake transmit diversity schemes (system 1 and system 2) using multiple transmit antennas in [2] and have also evaluated the system performance through the theoretical analysis and computer simulation. However, the performance of system 2 which transmit a signal using all antennas has not been evaluated for multi-user environment. Therefore in this paper, we analyze the performance of system 2 for multi-user environment and compare the performance with that of the already proposed system 1 which chooses only one antenna. From the numerical results, it is found that system 2 outperforms system 1 as the number of users increases while system 1 outperforms system 2 at a small number of users. Therefore in order to achieve the best system performance, the Pre-Rake transmit diversity type should be selected at the base station according to the number of users.

• KIEE International Transactions on Power Engineering
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• v.3A no.3
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• pp.124-129
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• 2003

As the power industry moves towards open competition, there has been a call for methodology to evaluate power system reliability by using composite interruption cost. This paper presents algorithms to evaluate the interruption cost of distribution power systems by taking into consideration the failure source and the composite customer interruption cost. From the consumer's standpoint, the composite customer interruption cost is considered as the most valuable index to estimate the reliability of a power distribution system. This paper presents new algorithms that take into account the load by customer type and failure probability by distribution facilities while calculating the amount of unserved energy by customer type. Finally, evaluation results of unserved energy and system interruption cost based on composite customer interruption cost are shown in detail.

• Proceedings of the KSR Conference
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• 2011.05a
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• pp.904-909
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• 2011

The development of train control system shall operate a series of processes like system designing, system production and system performance evaluation as a result of various requirements analysis presented in operation rules, operating guidelines for railway organizations etc, notified by the nation. Therefore, considering operation conditions, operation plan, linkage to railway network etc, the major document like system functional specifications, system development specifications, system test plans etc must be drawn up. In this paper we classify system operating scenarios required to prepare for system standard specification and system performance evaluation report of CBTC system for urban subways supporting unmanned automatic operation, and adjust each of the operating status.

• Proceedings of the KSR Conference
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• 2011.05a
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• pp.221-225
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• 2011

The railway system consists of many items such as sub-systems, equipments and parts to accomplish the required function. Also the railway system is very complex system that these items are connected with interface among items. According with this complexity, the process of system engineering is applied to the construction of new railway project to manage systematically. In addition, the research about system engineering is progressing in recent. The RAMS management is one part of system engineering, and is to assure the required safety and performance. Also, this RAMS should be managed through system life cycle. This paper show the case study of management of RAMS during construction and operation phase in respect of system life cycle. As a result of this research, the best way of RAMS management based on system engineering in operation phase for railway system is suggested.

• 제어로봇시스템학회:학술대회논문집
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• 2004.08a
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• pp.2023-2028
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• 2004

This paper reveals the utilization of the multi-gent system that based on the Blackboard system basis as the controller of Soccer Robot. This system is a portion of developing the Soccer Robot team for Robocup 2004 Competition. In this development, the intelligent control system was initiated by the combination of parallel and distributed blackboard structures with the principle design that generated from human body structures, which consists of the combination of two main systems, the organs system and the brain system. The system is designed using the control system theory based on Blackboard basis. Modification of the initial structures to corroborate the Soccer Robot and the structure's constituents are clarified accordingly. To demonstrate the idea, ITE-old team is given as a case study.

• Journal of Institute of Convergence Technology
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• v.10 no.1
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• pp.37-40
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• 2020

Automotive battery system consists of various components such as battery cells, mechanical structures, cooling system, and control system. Recently, various computational technologies are required to develop an automotive battery system. Physics-based cell modeling is used for designing a new battery cell by conducting optimization of material selection and composition in electrodes. Structural analysis plays an important role in designing a protective system of battery system from mechanical shock and vibration. Thermal modeling is used in development of thermal management system to maintain the temperature of battery cells in safe range. Finally, vehicle simulation is conducted to validate the performance of electric vehicle with the developed battery system.

• Journal of Korean Academy of Fundamentals of Nursing
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• v.15 no.3
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• pp.371-379
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• 2008

Purpose: The objective of the present study was to develop and evaluate a legal communicable diseases (LCDs) electronic system for infection control. Method: The system was developed through the procedure of analysis, design, implementation, application and evaluation, and was applied within an OCS (order communication system). Results: As indicated by the main menu, the present system is composed of an improved perception system for enhancing perception of LCDs, LCDs identification system, and improved efficiency in the report system. Detailed items included in the main menu are introduction and log-in screen, pop-up window for checking the outbreaks of LCDs, decision making icon, electronic signature icon, electronic report form, email system, etc. The total number of reports was greater after the application of the system (n=99) than before (n=80), and the adequacy of report time was statistically significantly higher after application of the system (P<0.05) Conclusion: The present system suggests a new method for LCDs report and infection control, and is expected to be adopted by other medical institutions in the future.

• The Journal of Society for e-Business Studies
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• v.6 no.3
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• pp.115-126
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• 2001

In constructive view, acquiring knowledge is made by experiences among members or elements. The knowledge in e-learning system can be extended up to knowledge of teachers and knowledge. of operating managers. We have many difficult problems to develop and manage e-1earning system because demanders on e-learning system have various. requirements. In traditional education system demanders are learners but in constructive view demanders can be extended to learners and teachers, operating mangers on e-learning system., In this study, we design and implement e-learning system named kedu V.1. Kedu V.1 is developed considering interactions of extended demanders of e-learning system in constructive view. And this system based on Linux operation system and MySQL, PHP. Also this system have efficient transplantation and portability capabilities and reduced cost and labor in implementation of real e-learning system

• Journal of the Korean Society of Systems Engineering
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• v.15 no.2
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• pp.108-115
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• 2019

The activities of managing and controlling the configuration of a system component over its life cycle are critical tasks in developing a high safety system as well as general system development. These configuration management activities should be defined through the management plan at the beginning of the life cycle, and should be performed continuously and systematically until the end of the project after the system or product development is completed. In this study, the configuration management process applied in the development of high safety railway signaling system was introduced and an efficient application proposals of it was proposed. In particular, configuration management through the establishment of a configuration management system based on computer tools is one of the important activities of maintaining the configuration integrity of the system or product.

• Journal of Advanced Marine Engineering and Technology
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• v.32 no.8
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• pp.1123-1128
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• 2008

Marine facilities like buoy, lighthouse are operated with stand alone power supply system. This power system can consist of a stand-alone type power system such as PV(Photovoltaic) system, wave system or hybrid system which is not cooperated with a commercial power system. Generally, PV power system for marine facilities can not supply a sufficient power to buoy, because it is so influenced from weather condition. For solving this problem the hybrid power system with PV and wave is studied on a various area, that is why a hybrid power system is requires to overcome these problems. This paper will describe a generation characteristic of WEC(Wave Energy Converter) for buoy, and an AFS(Anti-Fouling System) influence on WEC.