• Journal of Ocean Engineering and Technology
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• v.18 no.2
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• pp.33-38
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• 2004

All adaptive neural network controller has been developed for a model of an underwater vehicle. This controller combines a radial basis neural network and sliding mode control techniques. No prior off-line training phase is required, and this scheme exploits the advantages of both neural network control and sliding mode control. An on-line stable adaptive law is derived using Lyapunov theory. The number of neurons and the width of Gaussian function should be chosen carefully. Performance of the controller is demonstrated through computer simulation.

• Journal of Institute of Control, Robotics and Systems
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• v.11 no.10
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• pp.880-887
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• 2005

This paper presents a fault diagnosis(detection and isolation) approach for the Ammunition Transport Automation system(ATAS). Due to limited time and information available during its cyclic operation, the on-line fault detection algorithm consists of sequential test logics referring to the normal states, which can be considered as a kind of expert system. If a failure were detected, the off-line isolation algorithm finds the fault location through trained ART2 neural network. By the results of simulations and some on-line field test, it has been shown that the presented approach is effective enough and applicable to related automation systems.

• Journal of IKEEE
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• v.24 no.1
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• pp.364-367
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• 2020

This paper presents the off-grid PV-ESS system of sequential voltage control method applied to OR logic gate. The conventional off-grid PV-ESS system with the low-voltage series connection has problems due to capacity expansion. To solve these problems, this paper proposes a noble PV-ESS system with high efficiency and low cost by applying sequential voltage control technique of the high-voltage series connection of analog circuit type. The input voltage of DC to AC inverter can be converted from the low-voltage by the combinations of series connection of the conventional cascaded 24V solar cell unit modules to the high-voltage of 384V in battery. The output voltage of the battery was 384V as the each input voltage of three phase DC to AC inverter, and the each output voltage of three phase 10kW DC to AC inverter is designed to be AC380V@60Hz as the line to line rms voltage value. To prove the validity of the theoretical analysis by PSIM simulation, the operating characteristics of sequential voltage control system with OR logic gate were confirmed through experiment results.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.13 no.11
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• pp.5447-5451
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• 2012

This paper presents a pattern-switchable microstrip patch antenna with loop structure. The loop structure for switchable radiation beam pattern is connected with feeding line of the microstrip patch antenna. As changing switch on/off state, the radiation beam pattern can be changed. The target frequency is 2.4 GHz and maximum radiation gain is 3.2dBi. The proposed antenna is useful for diversity antenna and smart antenna in modern wireless communication including MIMO (Multi-Input Multi-Output) and WLAN system. The sizes of the rectangular patch and the ground plane are $28mm{\times}28mm$ and $40mm{\times}50mm$, respectively. The simulation and experimental results show that the antenna radiation pattern can be changed with switch on/off configuration.

• The Transactions of the Korean Institute of Power Electronics
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• v.12 no.1
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• pp.98-106
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• 2007

This paper represent improved on-line turn off angle control schemes for switched reluctance motors based on current control. For the purpose of finding the optimal commutation switching angle point with improved controller, it is utilized turn on and turn off position calculation with inductance vs. current vs. not linkage analysis method. The goal of proposed paper is the maximization of the energy conversion per stroke and torque ripple reduction and obtaining approximately flat-topped current waveform. The proposed control scheme is demonstrated simulation and on a prototype experimental system.

• Transactions of The Korea Fluid Power Systems Society
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• v.3 no.4
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• pp.14-20
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• 2006

Recently, the on-off solenoid valves have been focused on core technology in the fields of the production line of semi-conductor chips and the micro fluid chips for bio-medical applications. A key characteristics for on-off solenoid valve, operated by compressed air, are high speed response and great repeatability. Indeed, it is also important to keep the pressure on the cross-sectional area of the poppet to be constant regardless of the fluctuation of the pressure exerted on the ports. In this study, we have designed and analysed the high-speed and high flow rate on-off solenoid valve using the analogy of equivalent magnetic circuit and Finite Element Method (FEM) respectively. In case of poppet, flow field characteristics was analyzed by the variation of poppet and it was able to display flow field by changing the location of the poppet. Also, we verified possibility of the design through the static and dynamic pressure and the 3D simulation using distribution curve of the force by working the front poppet.

• 제어로봇시스템학회:학술대회논문집
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• 1989.10a
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• pp.589-594
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• 1989

In this paper, a programming system for robot-based manufacturing cell which can control and simulate manufacturing devices as well as robots in workcell is proposed and developed. The system is based on world model, and modem textual and object-level robot programming language and interactive graphic world modeler are used to construct and exploit world model. Graphic simulation is used as an efficient and easy to use debugging or verifying tool for user written robot programs. Machine dependency is minimized by adopting the hierarchical control structure and by assuming all the workcell components as virtual ones.

• 제어로봇시스템학회:학술대회논문집
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• 1990.10a
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• pp.327-332
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• 1990

Gunner primary sight stabilization system is a fully integrated sensor package designed to provide the stabilized Line-of-Sight. In this study, to improve disturbance rejection capabilities, two types of compensator (LQG/LTR, Lead-Lag) were designed and then stabilization performances were compared under severe off-road environment. Simulation results shows that the stabilization performances using LQG/LTR methodology is better than Lead-Lag methodology in spite of dynamic uncertainties.

• 제어로봇시스템학회:학술대회논문집
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• 1990.10a
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• pp.643-647
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• 1990

Gunner primary sight(GPS) stabilization system lays line of sight(LOS) to find out a target and transmits informations to the fire control system (FCS). In a moving vehicle, accuracy of LOS and FCS depends on the design of GPS and servomechanism system. The heavy vibration of vehicle on the severe off-road environment degenerates the stabilization capability of GPS. In this study, to stabilize of elevation for GPS using the variable structure control, we derived the dynamic equation of GPS system and designed the variable structure controller. Computer simulation results fulfilled the static and dynamic stability of GPS using the variable structure control.

• Proceedings of the KIPE Conference
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• 1998.07a
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• pp.265-268
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• 1998

This paper presents a soft-switching average current control PWM high power factor boost converter. Conventional boost ZVT-PWM converter has a disadvantage of hard-switching for auxiliary switch at turn-off. A soft switched auxiliary switch is proposed to achieve a high performance ZVT-PWM boost rectifier. The simulation and experimental results show that soft switching operation can be maintained for wide line and load range, which in turn improves the converter performance in terms of efficiency, switching noise and circuit reliability.