1. Ph.D. Student, School of Industrial and Systems Engineering, Univ. of Oklahoma, Norman, OK 73019.
2. Assistant Professor, School of Industrial and Systems Engineering, Univ. of Oklahoma, 202 W. Boyd St., Room 124, Norman, OK 73019 (corresponding author).
3. Dugan Professor, School of Industrial and Systems Engineering, Univ. of Oklahoma, Norman, OK 73019.