• 제어로봇시스템학회:학술대회논문집
• /
• 제어로봇시스템학회 2001년도 ICCAS
• /
• pp.177.1-177
• /
• 2001

This paper describes the design of a NUC(Non-uniformity Correction) module in MSC(Multispectral Camera) which will be a payload on KOMPSAT. This module is required inside a system with data compression module like MSC to minimize the loss of imagery due to non-uniform characteristics between CCD pixels when the imagery is received and processed on a ground station. It comprises Hotlink input/output for imagery data, RS-422 interface with main controller in MSC, a number of SRAMS for storing imagery data and parameters, FPGA controllers which control the entire NUC module under the control of main controller, etc. It inputs 8-channel imagery pixel data which consist of 2-channel MS(Multispectral) band and ...

• 제어로봇시스템학회:학술대회논문집
• /
• 제어로봇시스템학회 2001년도 ICCAS
• /
• pp.118.3-118
• /
• 2001

CLED (Contact Light Emitting Device) has three layers consisting of a transparent electrode, a light emitting layer and a substrate. When the substrate of the CLED comes in contact with a fingerprint under AC input voltage, it makes an electric field between the fingerprint and the device. Due to the electric field, the light is emitted along the ridgeline of the fingerprint. The intensity along the ridge on the surface of the CLED increase in proportion to the electric field. To achieve uniform performance of fingerprint verification devices, inspection system of CLED for quality control were required. In this research, we proposed the factors for quality controls such as dimensions of the CLED, uniformity ...

• Earthquakes and Structures
• /
• 제7권6호
• /
• pp.1025-1044
• /
• 2014

In this paper, a systematic technique is proposed for the optimal placement and design of nonlinear dampers for building structures. The concept of Output Frequency Response Function (OFRF) is applied to analytically represent the output frequency response of a building frame where nonlinear viscous dampers are fitted for suppression of vibration during earthquakes. An effective algorithm is derived using the analytical representation to optimally determine the locations and parameters of the nonlinear dampers. Various numerical examples are provided to verify the effectiveness of the optimal designs. A comparison of the vibration suppression performance with that of the frame structure under a random or uniform damping allocation is also made to demonstrate the advantages of the new designs over traditional solutions.

• Journal of Welding and Joining
• /
• 제18권4호
• /
• pp.48-54
• /
• 2000

Adaptive control in the robotic GMA(Gas Metal Arc) welding is employed to monitor information about weld characteristics and process parameters as well; as t modify those parameters to hold weld. The objectives of this paper are to realize the mapping characteristics of bead width through the neural network and multiple regression method as well as to select the most accurate model in order to control the weld quality(bead width0. The experimental results show that the proposed neural network estimator can predict bead width with reasonable accuracy, and guarantee the uniform weld quality.

• 제어로봇시스템학회:학술대회논문집
• /
• 제어로봇시스템학회 1990년도 한국자동제어학술회의논문집(국내학술편); KOEX, Seoul; 26-27 Oct. 1990
• /
• pp.382-387
• /
• 1990

In this paper, the dynamic modeling and tip position of rotating Timoshenko beam analyzed by means of FEM (finite element method) and Hyperstability MRAC(model referenced adaptive control) technique of each other. The governing equations of the rotating beams are drived from Hamilton's principle. The dynamic model of this multi-link is drived by Lagrange approach. The shear deformation and rotary inertia are incorporated into a finite element model for determining the bending frequencies of the rotating beam. Simulation results for uniform cantilever beams by using the MRAC are compared with the available results. It will be shown that the proposed method offers an accurate and effective one to solve the free vibration problems of rotating beams' stability.

• International Journal of Control, Automation, and Systems
• /
• 제5권2호
• /
• pp.128-137
• /
• 2007

A robust adaptive controller design for a class of Markovian jump parametric -strict-feedback systems is given. The disturbances considered herein include both uncertain nonlinearities and Wiener noises of unknown covariance. And they satisfy some bound-conditions. By using stochastic Lyapunov method in Markovian jump systems, a switching robust adaptive controller was obtained that guarantees global uniform ultimate boundedness of the closed-loop jump system.

• 대한전기학회:학술대회논문집
• /
• 대한전기학회 1997년도 추계학술대회 논문집 학회본부
• /
• pp.257-260
• /
• 1997

This paper designs the optimal PID controller for load frequency control on 2-area power system. Genetic algorithm is utilized to optimize parameters of PID controller which is applied to power system. Using two-point crossover, uniform crossover and one-point crossover, Search performance of genetic algorithm with each crossover method is considered. In case of load variation in 1-area, the dynamic characteristic of power system is considered. The simulation results show that the proposed PID controller is better control performance than PID controller using Ziegler-Nichols method.

• Journal of Power Electronics
• /
• 제11권4호
• /
• pp.520-526
• /
• 2011

This paper presents a balanced soft-chopping circuit and a modified PI controller for a high speed 4/2 Switched Reluctance Motor (SRM) with a 16 pulse per revolution encoder. The proposed balanced soft-chopping circuit can supply double the switching frequency in the fixed switching frequency of power devices to reduce current ripple. The modified PI controller uses maximum voltage, back-emf voltage and PI control modes to overcome the over-shoot current due to the time delay effect of current sensing. The maximum voltage mode can supply a fast excitation current with consideration of the hardware time delay. Then the back-emf voltage mode can suppress the current over-shoot with consideration of the feedback signal delay. Finally, the PI control mode can adjust the phase current to a desired value with a fast switching frequency due to the proposed balanced soft-chopping technology.

• 제어로봇시스템학회논문지
• /
• 제8권3호
• /
• pp.226-232
• /
• 2002

In this work, the quasi-static crawling of the four-bar mechanism is investigated. Since the crawling of the mechanism is based on sliding of contact points of the mechanism with the ground, interaction forces and friction forces at contact points of the mechanism with the ground should be computed. For this purpose, we introduce the concept of imaginary joints to find these forces and treat the closed mechanism as a serial one. Lastly, the required torques for the mechanism to crawl with respect to various configurations of the mechanism on a flat ground with uniform friction coefficient, based on sliding conditions of the mechanism in quasi-static equilibrium, are investigated.

• 한국정밀공학회:학술대회논문집
• /
• 한국정밀공학회 1995년도 춘계학술대회 논문집
• /
• pp.320-325
• /
• 1995

This study deals with the active vibration control system for an all-clamped rectangular plate with piezoceramic actuators and sensors. A line nonent algorithm (LMA) with the distributed modal sensitivity(DMS) is proposed to reduce the structural vibrations effectively and to select the optimal locations and the optimal directions (skewed angles) of uniform piezoelectric actuators or sensors. Experimental results show that eachmode can attenuated byabout 10 .approx. 13 dB in case a piezoelectric actuator generate the psuedo-random disturbances that excite the plate modes.