• Parasites, Hosts and Diseases
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• v.31 no.4
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• pp.321-330
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• 1993

F. seoulensis were obtained from artificially infected albino rats at 3, 4, 5, 6, 7 days after infection. The worms and metacercariae were washed in physiological saline solution, and fled with 10% neutral formalin. The acetylcholinesterase (AchE) stained by one histochemistry using acetylthiocholine iodide as substrate. Eserine, ism-OMPA and BW284C51 were used as inhibitors of AchE. The nervous system consists of three pairs longitudinal nerve trunks interconnected with excretory plexus in posterior half, and phinmc and oral sucker in anterior half of metacercariae and adults. The longitudinal nerve trunks are interconnected with transverse commissures and numerous circular commissures. Considerable numbers of circular commissures are interconnected with longitudinal nerve trunks tying on the surface of the worms. At each stage of juvenile worms, AchE and nonspecific cholinesterase activites were observed in the oral sucker, ventral sucker, pharynx and nerve system. Isoxymes of AchE in f seoderuts were separated into the two bands, 69 kDa and 132 kDa. The major band was 69 kDa.

• 제어로봇시스템학회:학술대회논문집
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• 1988.10a
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• pp.364-369
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• 1988

In this study, a model for the simulation of the material flow not only inside a robot cell with flexible handling sequence but also between robot cells is presented. A method for the connection of special simulation programs has been developed and a logic model between a real system and a simulation system is employed.

• Proceedings of the KIEE Conference
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• 1987.07a
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• pp.659-661
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• 1987

• Journal of Institute of Control, Robotics and Systems
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• v.19 no.5
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• pp.410-415
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• 2013

This paper proposes a bidirectional platoon control law using a coupled distance error based on the backstepping-like feedback linearization control method for an interconnected mobile agent system with a string structure. Unlike the previous results where the single agent was controlled using the only own information without other agents, the proposed control law cannot show the only distance error convergence of each agent, but also the string stability of the whole system. Also, the control performances are improved by the proposed control law in spite of low performance of bidirectional control strategy in the previous results. The proposed bidirectional platoon control algorithm is based on the backstepping-like feedback linearization control method. The position errors between each agent and the preceding and the behind agents are coupled by weighted summation. By the proposed control law, the distance error of each agent can converge to zero while the string stability is guaranteed when the coupled errors can converge to zero. To this end, the back-stepping control method is employed. The pseudo velocity input is determined considering the kinematic relationship between agents and the string stability. Then, the actual dynamic control input is determined to make the actual velocity converge to the pseudo velocity input. The stability analysis and the simulation results of the proposed method are included in order to demonstrate the practical application of the proposed algorithm.

• Journal of Energy Engineering
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• v.11 no.3
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• pp.216-223
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• 2002

Generation facilities of the power system are mainly classified into large-scale concentrated generation and small-scale dispersed generation, but generation planning of the Korea power system has been focusing on the large-scale generation so far. Recently, however, applications of dispersed generation sources including solar cell, fuel cell, wind power, etc. have been rapidly increasing and being strongly promoted, and such generation sources should be comprehensively considered in both planning and operating. Since it is not always possible that the dispersed generation alone meets all the load interconnected to it is especially when a fault occurs, interconnection into the existing utility is desirable and recommended. In relation to wind power generation systems interconnected at the low and extra high voltage levels, this paper performs the simulation and analysis of the system protection and suggests protection coordination plans on various faults which possibly occur.

• The Transactions of the Korean Institute of Electrical Engineers P
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• v.59 no.1
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• pp.100-105
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• 2010

This paper describes a capacity of distributed generation which will be interconnected at low voltage distribution systems. In order to set the capacity of distributed generation, a voltage variation of distribution system is considered. Besides, the capacity of distributed generation is classified according to a capacity of pole transformer and loads. The system constructions in this paper are analyzed by using PSCAD/EMTDC. In the immediate future, it is expected to increase the installation of New and renewable energy systems which are generally interconnected to distribution power systems in the form of distributed generations like photovoltaic system, wind power and fuel cell. So the study of this kind would be needed to limit the capacity of distributed generation.

• The Transactions of the Korean Institute of Electrical Engineers A
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• v.49 no.2
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• pp.62-69
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• 2000

In this paper, we design a GA-fuzzy precompensated PID controller for the load frequency control of two-area interconnected power system. Here, a fuzzy precompensated PID controller is designed as a fuzzy logic-based precompensation approach for PID controller. This scheme is easily implemented simply by adding a fuzzy precompensator to an existing PID controller. And we optimize the fuzzy precompensator with a genetic algorithm for complements the demerit such as the difficulty of the component selection of fuzzy controller, namely, scaling factor, membership function and control rules. Simulation results show that the proposed control technique is superior to a conventional PID control and a fuzzy precompensated PID control in dynamic responses about the load disturbances of power system and is convinced robustness reliableness in view of structure.

• The Transactions of The Korean Institute of Electrical Engineers
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• v.61 no.8
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• pp.1099-1106
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• 2012

Microgrid is a new electrical energy system that composed of various generators, renewable energy, batteries and loads located near the electrical customers. When Microgrid is interconnected with large power system, Microgrid don't need to control the frequency. But in case of the outage or faults of power system, Microgrid should control the frequency to prevent the shutdown of Microgrid. This paper presents the frequency control methods using the droop function, being used by synchronous generators and EMS(Energy Management System). Using droop function, two battery systems could share the load based on locally measured signals without any communications between batteries. Also, we suggest that EMS should control the controllable distributed generators as P/Q control modes except batteries to overcome the weakness of droop function. Finally we suggest the two batteries systems to prolong the battery's life time considering the economical view. The validation of proposed methods is tested using PSCAD/EMTDC simulations and field test sites at the same time.

• 전기의세계
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• v.24 no.5
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• pp.67-71
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• 1975

A dynamic stability analysis of a large interconnected power system takes much time even though the modern large computer is used because of the high order of the system dynamic equations. By the necessity of the low order power system models, a simplified power system model of the generator with the high speed solid state exciter is developed in this paper. The usefulness of the reduced model is confirmed by comparing its eigenvalues and the transient responses with those of the original model in the single machine to infinite bus power system.

• Journal of the Korean Institute of Telematics and Electronics
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• v.19 no.4
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• pp.15-20
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• 1982

Stabilization by decentralized control is an important problem in large scale systems and there has been an increasing interest in this area. The objective of this paper is to obtain the sufficient condition for an interconnected system to be stabilited by local feedback. Recently there has been many papers about this, and we further broaden the class of interconnections for which we can find a decentralized control to stabilize the overall system. The interconnection matrix may take any arbitrary time invariant values and this implies connective stability in some sense. The assumed model is mire general than most of previous ones, and as a special case, when each subsystem is given by companion form of a single inputs the result is compared with that of Ikeda and Siljak. The obtained result is illustrated by examples.