College of Engineering

Abstract: In recent years, the scale of power systems has been expanding and with that expansion stable power supply and smooth power system operation is becoming increasingly important. One measure for increasing stability is to improve the main circuits by raising the voltage or employing series capacitors in power transmission lines, but the generator exciter control method, which makes use of AVR (automatic voltage regulator), is attracting attention because of its inherent cost advantage.

A robust controller design for a micro motion system represented by a piezoelectric bimorph actuator is considered. The dynamic model of the piezoelectric actuator with nonlinear hysteresis is presented. The nonlinear dynamics of the actuator are first linearized using the stochastic equivalent linearization method. Then a robust controller is designed for the piezoelectric actuator system using a state space approach which guarantees stability and good performance of the controlled system. Three approaches are considered.

Abstract: Wireless networking is a double-edged sword. The interception of wireless communications has existed as a problem when sensitive data are exchanged. In order to protect the data from eavesdroppers, various forms of encryption have been used to scramble the data. The IEEE 802.11 standard for wireless network describes an encryption protocol called Wired Equivalent Privacy (WEP). The goal of WEP is to make WLAN communication as secure as wired LAN data transmissions would be, by protecting link-layer communication from eavesdropping and other attacks.