DIFFERENTIAL EVOLUTION FOR OPTIMIZATION OF PID GAIN IN ELECTRICAL DISCHARGE MACHINING CONTROL SYSTEM

ABSTRACT PID controller of servo control system maintains the gap between Electrode and workpiece in Electrical Dis- charge Machining (EDM). Capability of the controller is significant since machining process is a stochastic phenomenon and physical behaviour of the discharge is unpredictable. Therefore, a Proportional Integral Derivative (PID) controller using Differential Evolution (DE) algorithm is designed and applied to an EDM servo actuator system in order to find suitable gain parameters. Simulation results verify the capabilities and effectiveness of the DE algorithm to search the best configuration of PID gain to maintain the electrode position. Keywords: servo control system; electrical discharge machining; proportional integral derivative; con- troller tuning; differential evolution

Active integrated antenna with direct conversion receiver design

For a microwave engineer, “An active antenna is an activemicrowave circuit in which the output or input port is free spaceinstead of a conventional 50 interface.” For an antenna designer,“Active antenna is an antenna that possesses built-in signal-andwave-processing capabilities such as mixing and amplification.” Insimple words an active integrated antenna can provide certaincircuit functions such as resonance, filtering, and duplexing, inaddition to its original role as a radiating element

Numerical modelling of sound intensity based on sound absorption coeficient of WCPP at 40% perforation ratio

The boundary element method (BEM) is a numerical method that solves boundary value problems through the boundary integral equation (BIE) formulations. The applications of direct BIE formulations started in the early 1960 ‘s by Jaswon on a potential problem. This work was extended by Rizzo to solve the electrostatic problem. Since then, extensive research efforts have been made to develop BIE formulations for a variety of problems in applied mechanics. As the result, the BEM has become an attractive numerical tool useful in many engineering applications, such as acoustics, heat transfer, solid mechanics, structural mechanics, fluid mechanics, fracture mechanics, geomechanics, electromagnetic and so on