1. National Energy Technology Laboratory, 626 Cochran Mill Road, Pittsburgh, PA 15236, USA
2. NETL Support Contractor, 626 Cochran Mill Road, Pittsburgh, PA 15236, USA
3. Presently with the National Institute for Occupational Safety and Health, Pittsburgh, PA 15236, USA
4. Department of Electrical and Computer Engineering, Carnegie Mellon University, 5000 Forbes Avenue, Pittsburgh, PA 15213, USA