1 23 Journal of The Institution of Engineers (India): Series C Mechanical, Production, Aerospace and Marine Engineering ISSN 2250-0545 J. Inst. Eng. India Ser. C DOI 10.1007/s40032-014-0143-z An Accelerated Particle Swarm Optimization Algorithm on Parametric Optimization of WEDM of Die-Steel V. Muthukumar, A. Suresh Babu, R. Venkatasamy & N. Senthil Kumar