• Proceedings of the KIEE Conference
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• 2005.07a
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• pp.580-582
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• 2005

This paper presents a new method which applies a genetic algorithm(GA) for determining which sectionalizing switch to operate in order to solve the distribution system loss minimization re-configuration problem. The distribution system loss minimization re-configuration problem is in essence a 0-1 planning problem which means that for typical system scales the number of combinations requiring searches becomes extremely large. In order to deal with this problem, a new a roach which applies a GA was presented. Briefly, GA are a type of random number search method, however, they incorporate a multi-point search feature. Further, every point is not is not separately and respectively renewed, therefore, if parallel processing is applied, we can expect a fast solution algorithm to result.

• The Transactions of the Korean Institute of Electrical Engineers A
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• v.51 no.9
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• pp.433-440
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• 2002

The addition of switches to a distribution feeder does, in general, increase reliability by decreasing the duration of the outage of many to the customers on the feeder. To cover its service area so that feeder-level delivery reaches sufficiently close to all customers, feeders typically split their routes many times, in what is often called a lateral feeder. It is interesting to note, however, that the effectiveness of a switch is very much dependent on the types of lateral feeder. The types of lateral are classified into two types. The first is loop lateral feeder that can connect its load to an adjacent feeder through a tie line in case that a fault occurs in its feeder and it is laid out so that every feeder has complete fault backup through re-switching of its loads to other sources like a main feeder The second is the radial lateral feeder cannot connect its load to an adjacent line, no provision is made for contingency backup of feeders. There are no other circuits in the radial lateral feeder form which to restore power. In this study, we evaluate the effectiveness of a switch installation between on the radial and loop lateral feeders to increase reliability by decreasing the duration of the outage. These results can help power utility to design the switch layouts on the radial and loop lateral feeder system.

• Journal of the Korea Society of Computer and Information
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• v.12 no.3
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• pp.147-153
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• 2007

Task scheduling is an essential part of any computer system for allocating tasks to a processor of the system among various competitors. As we know, in real-time system, the failure of scheduling a hard real-time task my lead to disastrous consequence. Besides efficiency, resource and speed, real-time system has to take time constraint in serious consideration. This paper proposes a priority-driven scheduling algorithm for real-time multiprocessor system. which is called L-RE coordinates algorithm. L-RE coordinates is a new way of describing the task scheduling problem. In the algorithm, we take both deadline and laxity into consideration for allocating the priority. The simulation result shows that the new algorithm is viable and performance better than EDF and LLF algorithm on schedulability and context switch respectively.

• Proceedings of the KSME Conference
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• 2003.11a
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• pp.1530-1535
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• 2003

The automatic load transfer switch (ALTS) typically automatically transfers electrical loads from a normal electrical power source to an emergency electrical power source upon reduction or loss of normal power source voltage. It can also automatically re-transfer the load to the normal power source when the normal voltage has been restored within acceptable limits. The transfer operation of ALTS is accomplished by a spring-driven linkage mechanism. In this paper we build a dynamic model of driving mechanism for ALTS using ADAMS and checked the characteristics of the transfer operation. Finally we performed a detailed design of the driving mechanism through results of analysis and confirmed it to satisfy design requirements.

• Proceedings of the KIEE Conference
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• 1998.07f
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• pp.2027-2029
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• 1998

We have developed a compact high frequency switch mode converter (HFSMC) power supply with DC 50 kV output voltage and 10 kW output power. Since the inverter circuit uses 25 kHz rescharging scheme, the current is flowing with t kHz. For the efficient output voltage transform performed a simple design process using the transformer principle and the commercial specification. For the DC 50 kV output, we employed 7 pa windings of secondary coils for the series stac connection of the output with full-bridge rectifi In this paper the design detail and the test re the high frequency transformer together with HFSMC power supply are presented.

• Proceedings of the KIEE Conference
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• 2000.07c
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• pp.2135-2137
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• 2000

Usually arc phenomena are not easily characterized due to unstable behavior very short existence-times, high temperature and the required isolation of measurement instruments. This paper presents some arc-behaviors in a rotary arc gap-switch(RAG) using a 500kJ capacitor bank. It includes the speed variations of the rotating arc, the impacts of the oscillating current on the arc initiations and re-ignitions. Changes in the arc-dimension with respect to time and current magnitudes are also analyzed.

• Proceedings of the Korean Vacuum Society Conference
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• 2012.08a
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• pp.343-344
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• 2012

It has been known since the mid 1960s that Ag can be photodissolved in chalcogenide glasses to form materials with interesting technological properties. In the 40 years since, this effect has been used in diverse applications such as the fabrication of relief images in optical elements, micro photolithographic schemes, and for direct imaging by photoinduced Ag surface deposition. ReRAM, also known as conductive bridging RAM (CBRAM), is a resistive switching memory based on non-volatile formation and dissolution of a conductive filament in a solid electrolyte. Especially, Ag-doped chalcogenide glasses and thin films have become attractive materials for fundamental research of their structure, properties, and preparation. Ag-doped chalcogenide glasses have been used in the formation of solid electrolyte which is the active medium in ReRAM devices. In this paper, we investigated the nature of thin films formed by the photo-dissolution of Ag into Ge-Se glasses for use in ReRAM devices. These devices rely on ion transport in the film so produced to create electrically programmable resistance states. [1-3] We have demonstrated functionalities of Ag doped chalcogenide glasses based on their capabilities as solid electrolytes. Formation of such amorphous systems by the introduction of Ag+ ions photo-induced diffusion in thin chalcogenide films is considered. The influence of Ag+ ions is regarded in terms of diffusion kinetics and Ag saturation is related to the composition of the hosting material. Saturated Ag+ ions have been used in the formation of conductive filaments at the solid electrolyte which is the active medium in ReRAM devices. Following fabrication, the cell displays a metal-insulator-metal structure. We measured the I-V characteristics of a cell, similar results were obtained with different via sizes, due to the filamentary nature of resistance switching in ReRAM cell. As the voltage is swept from 0 V to a positive top electrode voltage, the device switches from a high resistive to a low resistive, or set. The low conducting, or reset, state can be restored by means of a negative voltage sweep where the switch-off of the device usually occurs.

• Proceedings of the KIEE Conference
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• 2006.10b
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• pp.212-215
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• 2006

This paper a new method which applies a genetic algorithm for determining which sectionalizing switch to operate in order to solve the distribution system loss minimization re-configuration problem. In addition, the proposed method introduces a ultra efficient MMP tracking in a solar power generation system.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 2006.11a
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• pp.394-395
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• 2006

This paper a new method which applies a genetic algorithm for determining which sectionalizing switch to poerate in order to solve the distribution system loss minimization re-configuration problem. In addition, the proposed method introduces a ultra efficient MMP tracking in a solar power generation system.

• Proceedings of the KIEE Conference
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• 2006.11a
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• pp.75-77
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• 2006

This paper a new method which applies a genetic algorithm for determining which sectionalizing switch to poerate in order to solve the distribution system loss minimization re-configuration problem. In addition, the proposed method introduces a ultra efficient MMP tracking in a solar power generation system.