• 제어로봇시스템학회:학술대회논문집
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• 제어로봇시스템학회 1994년도 Proceedings of the Korea Automatic Control Conference, 9th (KACC) ; Taejeon, Korea; 17-20 Oct. 1994
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• pp.531-536
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• 1994

Wrapping machines in cigarette factories are equipped with indexing drive units with roller gear cam. At present there are no simple, visual, diagnostic techniques for predicting failure in these nits at an early stage. This paper proposes that failure could be predicted by using either a modified version of kurtosis, or the Wigner distribution method. The nonlinear vibration model proposed in this paper takes into consideration the play between the m and the cam follower, and precisely simulates the actual vibration. Statistics on the variance in play, obtained from the data on time history, call then be used to evaluate the effects of tile mage oil the cam and cam follower.

• 제어로봇시스템학회:학술대회논문집
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• 제어로봇시스템학회 2005년도 ICCAS
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• pp.1474-1477
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• 2005

This paper is proposed maximum torque per ampere of induction motor using fuzzy-neural networks controller. Operation of maximum torque per ampere is achieved when, at a given torque and speed, the slip frequency is adjusted to that so that the stator current amplitude is minimized. This paper introduces a induction motor drive system with fuzzy-neural networks controller. A neural network-based architecture is described for fuzzy logic control. The characteristic rule and their membership function of fuzzy system are represented as the processing nodes in the neural network structure. This paper is proposed the analysis as well as the simulation results to verify the effectiveness of the new method.

• 천문학회보
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• 제39권2호
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• pp.99.2-99.2
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• 2014

We investigate how a solar eruption occurs in an environment where a solar wind exists during a pre-eruptive phase. To understand it, we have performed three-dimensional simulations based on a zero-beta magnetohydrodynamic (MHD) equations in various ways to drive an eruption with a solar wind. A pre-eruptive state is derived by applying a nonlinear force-free reconstruction method to a flux emergence full MHD simulation. We discuss what is the most appropriate way to drive a solar wind-related eruption.

• 한국정보디스플레이학회:학술대회논문집
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• 한국정보디스플레이학회 2008년도 International Meeting on Information Display
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• pp.1189-1192
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• 2008

A new mercury-free flat fluorescent lamp with a single cell having dimension 2.2inches across the diagonal, had been developed which shows a wide, stable operating voltage margin, high luminance and luminous efficacy by adopting the bipolar pulse drive scheme. In this paper, the single cell is expanded into a multi-structured configuration to realize a 32inch sized panel across the diagonal by a simple repetition of the single cells. A driving scheme is proposed for a 2-bit areal selective dimming using dual auxiliary electrodes and bipolar drive scheme.

• 전력전자학회:학술대회논문집
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• 전력전자학회 1999년도 전력전자학술대회 논문집
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• pp.84-87
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• 1999

This paper proposes an interfaces control system to drive a ultrasonic motors(USMs). To touch surfaces and objects created within a virtua environment, the 3 DOF force-reflecting interfaces provides force feedback to users, so to feel touching real things. To effectively display the mechanical impedance of the human hand we need a device with specific characteristics, such as low inertia almost zero friction and very high stiffness. As an actuator for direct drive method, the USMs have many good advantages satisfied these conditions over conventional servo motors. To estimate capability of this interface, we did an experiment. The device works very well, as user are able to detect the edge of the wall and the stiffness of the button.

• 대한전기학회논문지:전기기기및에너지변환시스템부문B
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• 제54권1호
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• pp.40-46
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• 2005

This paper has investigated the speed sensorless indirect vectorcontrol of a two-phase induction motor to implement adjustable-speed drive for low-power applications. The sliding mode observer estimates rotor speed. The convergence of the nonlinear time-varying observer along with the asymptotic stability of the controller has been analyzed. To define the control action which maintains the motion on the sliding manifold, an "equivalent control" concept is used. It has been simulated and implemented on a sensorless indirect vector drive for 150W two-phase induction motor. The simulation and experimental results demonstrate effectiveness of the estimation method.

• JSTS:Journal of Semiconductor Technology and Science
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• 제16권1호
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• pp.58-69
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• 2016

This paper describes the design and implementation of a new diode clamped multilevel inverter for variable frequency drive. The diode clamp multilevel inverter has been widely used for low power, high voltage applications due to its superior performance. However, it has some limitations such as increased number of switching devices and complex PWM control. In this paper, a new topology is proposed. New topology requires only (N-1) switching devices and (N-3) clamping diodes compared to existing topology. A modified APO-PWM control method is used to generate gate pulses for inverter. The proposed inverter topology is coupled with single phase induction motor and its performance is tested by MATLAB simulation. Finally, a prototype model has built and its performance is tested with single phase variable frequency drive.

• 한국정밀공학회:학술대회논문집
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• 한국정밀공학회 2001년도 춘계학술대회 논문집
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• pp.186-189
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• 2001

In a precise control system, the Lu-Gre friction model has often been used to describe the nonlinear friction. For the XY table system with this friction model, we identified the friction parameters and designed nonlinear observer. The nonlinear friction effects could be removed within appropriate position tracking errors and control inputs through experiments. Also, we designed the nonmodel-based SMC system to compensate the nonlinear friction. Through experiments, it is shown that this method has the similar performance compared with the nonlinear observer system and is useful when friction parameters are hard to identify except the problem of input chattering.

• 한국소음진동공학회:학술대회논문집
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• 한국소음진동공학회 2001년도 춘계학술대회논문집
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• pp.504-509
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• 2001

CD-ROM drive is improved in rotation speed up to 10,000 rpm. But Vibration and Noise are also increased simultaneously more and more. So many attempts are tried to reduce the unexpected effects. Most attempts are not enough to cover the increasement of Noise and Vibration. Merely availed tries are accumulated in many part and it makes the structure complicated. The Axiomatic approach could arrange the order of design and estimate the optimum design in good oder. In Axiomatic Approach, the composition is divided by Customer Requirement, Functional Requirement, Design Parameter and Design Matrix in large portion. This method also could show more effective way to design before making a prototype.

• 제어로봇시스템학회논문지
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• 제4권5호
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• pp.592-599
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• 1998

In this paper, we design a tracking controller which satisfies transient response specifications and maintains tracking error within a tolerable limit for the uncertain track-following system of an optical disk drive. To this end, a robust $H_{\infty}$ control problem with regional stability constraints and sinusoidal disturbance rejection is considered. The internal model principle is used for rejecting the sinusoidal disturbance caused by eccentric rotation of the disk. We show that a condition satisfying the regional stability constraints can be expressed in terms of a linear matrix inequality (LMI) using the Lyapunov theory and S-procedure. Finally, a tracking controller is obtained by solving an LMI optimization problem involving two linear matrix inequalities. The proposed controller design method is evaluated through an experiment.