Raul G. Longoria, Professor, Walker Department of Mechanical Engineering, University of Texas at Austin. Professor Longoria has over 30 years of experience in the field and has taught the methods described in this book in undergraduate and graduate level courses. He has applied these multidisciplinary modeling and simulation methods in a wide-range of industry and government projects throughout his academic research and consulting career. Joseph J. Beaman, Professor and former Department Chair (2001 to 2012) of Walker Department of Mechanical Engineering, University of Texas at Austin, has more than 40 years of experience in the field. He was one of the founders of DTM Corporation (now merged with 3D systems). Professor Beaman was elected to the National Academy of Engineers and the National Academy of Inventors, given the CIRP Nicolau award, and elected Honorary Member of ASME.