University of North Carolina at Chapel Hill, 27599 Chapel Hill, NC, USA. swaldon@cs.unc.edu.|University of North Carolina at Chapel Hill, 27599 Chapel Hill, NC, USA. swaldon@cs.unc.edu.|Applied Research Lab, Faculty of Natural and Applied Sciences, Trinity Western University Canada, Langley, BC, Canada. herbert.tsang@twu.ca.|Applied Research Lab, Faculty of Natural and Applied Sciences, Trinity Western University Canada, Langley, BC, Canada. herbert.tsang@twu.ca.