• The Transactions of the Korean Institute of Electrical Engineers A
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• v.49 no.1
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• pp.26-30
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• 2000

Switching of the transmission lines(T/L) is one of the methods for wuppressing the short circuit capacity. This paper presents the T/L switching operation by using the Hopfield neural network(HNN). The switching of T/L can make the line powers and the bus voltages deteriorated, as well as the fault current decreased. Such an insecure state should be avoided when the T/L is operated to be open. In this studies, the inequality constraints are formulated into the objective function to be incorporated with the HNN. Test results show that the convergence characteristics of HNN lead to the adequate solution of T/L switching.

• Proceedings of the KIEE Conference
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• 2001.11c
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• pp.15-17
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• 2001

This paper deals with a design problem of a switching-type fuzzy-model-based controller for a nonlinear system. Takagi-Sugeno(TS) fuzzy model and duffing forced-oscillation system are employed in designing the switching-type fuzzy controller. Finally, we analyze the stability of the global system controlled by the proposed controller.

• 제어로봇시스템학회:학술대회논문집
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• 2001.10a
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• pp.152.1-152
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• 2001

This paper presents a high performance and cost effective way by using an FPGA circuit to implement torque controller so that the SRM can operate at high speed. In order to increase the operating speed, we need to implement both the torque and the current controllers by using an FPGA. However, it is difficult to implement all of the torque controller in the FPGA. Moreover, implementation of a time critical part is sufficient for improving the performance. One of the time critical part is the switching angle control. In this study, torque controller which calculate the switching on and commutation angles is implemented in PC because these angle are a function of rotor velocity which is varied slowly, and switching angle controller ...

• Journal of the Korean Institute of Telematics and Electronics
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• v.17 no.6
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• pp.86-92
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• 1980

This paper dealt with an oscillator which can be integrated and 1 he switching characteristics of the transistor as a component of multistage switching circuits . The switching characteristics were analyzed by utilizing the base voletare and the charactistics of the minit step function. Taking the storage time of the transistor into consideration, the transistor is considered as a time delay device, and an integrable time delay circuit an osicillator are realized.

• 한국정보디스플레이학회:학술대회논문집
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• 2009.10a
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• pp.498-501
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• 2009

Electrophoretic displays (EPDs) are attracting considerable attentions as a paper-like display. Especially, Electrophoretic cell consists of micron-sized, charged particles dispersed in a viscous fluid. When an external electric field is applied, the charged particles move with a speed proportional to the particle mobility and the local field strength. In electrophoretic displays fast switching times are required, so knowing the particle mobility is very important. In this paper, we study a novel simulation for calculating the particle motions submerged in a viscous fluid for horizontal switching electrophoretic cell.

• Journal of Institute of Control, Robotics and Systems
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• v.3 no.6
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• pp.576-581
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• 1997

DC-DC converter with chopper is seen to have problems, such as, loop instability and degradation of transient response, due to the interaction between input filter and switching regulator. In this paper, the switching regulator consisting of input filter and double chopper is analyzed, and the state space model at continuous current mode and the transfer function between duty ratio of switching pulse and output voltage are derived. The controller in this paper is designed as feedforward(P) and feedback(PI) control scheme to minimize the variation of output voltage, and computer simulation results are presented to show the performance of the proposed controller.

• Proceedings of the KIPE Conference
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• 2014.07a
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• pp.301-302
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• 2014

This paper describes four switch three-phase Z-source rectifier with improved switching characteristics. This configuration has some advantages switching loss and optimal drive circuit. The rectifier has buck-boost function by shoot-through state. Also, the rectifier has the advantage of decreasing inrush current in start-up and transient states. In order to reduce harmonics PWM modulation technique with a variable index has been suggested. Four switch three-phase Z-source rectifier with improved switching characteristics can output stable DC voltage at the same time decreasing the system's harmonic current. And also the paper presents an application of DCC method in Z-source rectifier. Principles and dynamics of the system are discussed in detail. After having viewed the results we can confirm that the proposed method is eligible and efficient.

• Journal of the Korean Mathematical Society
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• v.56 no.4
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• pp.947-984
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• 2019

We provide two shifted analogues of the tableau switching process due to Benkart, Sottile, and Stroomer; the shifted tableau switching process and the modified shifted tableau switching process. They are performed by applying a sequence of elementary transformations called switches and shares many nice properties with the tableau switching process. For instance, the maps induced from these algorithms are involutive and behave very nicely with respect to the lattice property. We also introduce shifted generalized evacuation which exactly agrees with the shifted J-operation due to Worley when applied to shifted Young tableaux of normal shape. Finally, as an application, we give combinatorial interpretations of Schur P- and Schur Q-function related identities.

• Proceedings of the Korean Institute of Communication Sciences Conference
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• 1986.04a
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• pp.169-176
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• 1986

The function of administration and maintenance on the TDX-1 digital switching system, which have been developed in ETRI(Electrotechnology and Telecommunications Research Institute), are reported. In administration, the functions of charging, statistics, data handling, man-mechine communication and I/0 device control are described. In maintenance, the function of fault detection and processing, status handling and alarm described.

• Journal of the Korea Institute of Information and Communication Engineering
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• v.13 no.5
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• pp.922-930
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• 2009

An optimized PWM switching strategy for an induction motor voltage control is developed and demonstrated. Space vector modulation in voltage source inverter offers improved DC-bus utilization and reduced commutation losses and has been therefor recognized the preferred PWM method especially in case of digital implementation. An optimized PWM switching strategy for an induction motor voltage control consists of switching between the two active and one zero voltage vector by using the proposed optimal PWM algorithm. The preferred switching sequence is defined as a function of the modulation index and period of a carrier wave. The sequence is selected by using the inverter switching losses and the current ripple as the criteria. For low and medium power application, the experimental results indicate that good dynamic response and reduced harmonic distortion can be achieved by increasing switching frequency.