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Stephen Unwin

Stephen Unwin

Pacific Northwest National Laboratory
PO Box 999
Richland, WA 99352
(509) 375-2448

Biography

Dr. Stephen Unwin manages the Nuclear Regulatory market sector within Pacific Northwest National Laboratory's Energy and Environment Directorate. Dr. Unwin joined PNNL in 2006, and for most of his tenure has worked as the principal scientist in EED's Risk and Decision Sciences group. In 2009, for approximately one year, he served on an interim basis as the manager of EED’s Sustainable Environmental Systems market sector. Dr. Unwin is a physicist who began his career with the United Kingdom Atomic Energy Authority. It was as a technical attaché that he first came to the United States, stationed at Sandia National Laboratories as an information liaison between the U.S. Nuclear Regulatory Commission (NRC) Severe Accident Program and the British government. He founded risk management groups at Brookhaven National Laboratory, SAIC, and Battelle. Dr. Unwin was an author of the landmark NRC risk study, NUREG-1150, and was a prime contractor to the Canadian Nuclear Safety Commission as they established risk-informed regulation. In 1996 he founded Unwin Company, which is a continuing risk management resource to the private sector and the U.S. Department of Energy.

Education and Credentials

  • Ph.D., Theoretical Physics, University of Manchester, U.K., 1980
  • B.Sc., Physics (First Class Honors), Imperial College of Science and Technology, University of London, U.K., 1977

Awards and Recognitions

  • Awarded United States flag by the National Aeronautics and Space Administration "in recognition of contributions made to the Ulysses mission launched October 6, 1990."
  • Awarded a Certificate of Appreciation by the U.S. Nuclear Regulatory Commission "in recognition of [Dr. Unwin's] outstanding contribution to NUREG-1150 resulting in a significant advancement in the state of technology of probabilistic risk analysis and a major contribution to the Nuclear Regulatory Commission's severe accident program."

PNNL Publications

2016

2015

2013

  • Unwin SD, KI Johnson, WJ Ivans, Jr, and PP Lowry. 2013. "A PROPOSED METHOD FOR ESTIMATING FAILURE RATES OF DEGRADED PASSIVE COMPONENTS IN THE NRC SIGNIFICANCE DETERMINATION PROCESS." Transactions of the American Nuclear Society 109(1):2049-2050. 
  • Unwin SD, PW Eslinger, and KI Johnson. 2013. "ROBUSTNESS OF DECISION INSIGHTS UNDER ALTERNATIVE ALEATORY/EPISTEMIC UNCERTAINTY CLASSIFICATIONS." In International Topical Meeting on Probabilistic Safety Assessment and Analysis (PSA 2013), September 22-27, 2013, Columbia, South Carolina, vol. 1, pp. 569-580.  American Nuclear Society, La Grange, IL. 
  • Holmes AE, LH Sego, BJM Webb-Robertson, HW Kreuzer, RM Anderson, SD Unwin, MR Weimar, MF Tardiff, and CD Corley. 2013. An Approach for Assessing the Signature Quality of Various Chemical Assays when Predicting the Culture Media Used to Grow MicroorganismsPNNL-22126, Pacific Northwest National Laboratory, Richland, WA. 

2012

2011

  • Unwin SD, PP Lowry, and MY Toyooka. 2011. "A Methodology Supporting the Risk-Informed Management of Materials Degradation." In Proceedings of the 2011 American Nuclear Society Winter Meeting and Nuclear Technology Expo, October 30-November 3, 2011, Washington DC.  American Nuclear Society, La Grange Park, IL. 
  • Unwin SD, PP Lowry, RF Layton, Jr, MB Toloczko, KI Johnson, and SE Sanborn. 2011. Physics-Based Stress Corrosion Cracking Component Reliability Model cast in an R7-Compatible Cumulative Damage FrameworkPNNL-20596, Pacific Northwest National Laboratory, Richland, WA. 
  • Unwin SD, PP Lowry, RF Layton, Jr, PG Heasler, and MB Toloczko. 2011. "Multi-State Physics Models of Aging Passive Components in Probabilistic Risk Assessment." In International Topical Meeting on Probabilistic Safety Assessment and Analysis (PSA 2011), March 13-17, 2011, Wilmington, North Carolina, vol. 1, pp. 161-172.  Amercian Nuclear Society, La Grange Park, IL. 
  • Unwin SD, RH Moss, JS Rice, and MJ Scott. 2011. Characterizing Uncertainty for Regional Climate Change Mitigation and Adaptation DecisionsPNNL-20788, Pacific Northwest National Laboratory, Richland, WA. 
  • Coles GA, SD Unwin, GM Holter, RB Bass, and JE Dagle. 2011. "Defining resilience within a risk-informed assessment framework." International Journal of Risk Assessment and Management 15(2/3):171-185.  doi:10.1504/IJRAM.2011.042115
  • Paulson PR, TE Carroll, C Sivaraman, PA Neorr, SD Unwin, and SS Hossain. 2011. "Simplifying Probability Elicitation and Uncertainty Modeling in Bayesian Networks." In Proceedings of the 22nd Midwest Artificial Intelligence and Cognitive Science Conference (MAICS 2011), April 16-17, 2011, Cincinnati, OH, ed. S Visa, A Inoue and AL Ralescu, pp. 114-119.  Omnipress, Madison, WI. 
  • Unwin SD, A Sadovsky, EC Sullivan, and RM Anderson. 2011. Risk-Informed Monitoring, Verification and Accounting (RI-MVA). An NRAP White Paper Documenting Methods and a Demonstration Model for Risk-Informed MVA System Design and Operations in Geologic Carbon SequestrationPNNL-20808, Pacific Northwest National Laboratory, Richland, WA. 
  • Unwin SD, PP Lowry, MY Toyooka, and BE Ford. 2011. "DEGRADATION SUSCEPTIBILITY METRICS AS THE BASES FOR BAYESIAN RELIABILITY MODELS OF AGING PASSIVE COMPONENTS AND LONG-TERM REACTOR RISK." In Proceedings of the ASME 2011 Pressure Vessels & Piping Conference (PVP2011), July 17-21, 2011, Baltimore, Maryland, pp. Paper No. PVP2011-58073.  ASME , New York, NY. 

2010

  • Unwin SD, PP Lowry, and MY Toyooka. 2010. "A New Class of Risk-Importance Measures to Support Reactor Aging Management and the Prioritization of Materials Degradation Research." In 10th International Probabilistic Safety Assessment & Management Conference - PSAM10, June 7-11, 2010, Seattle, WA.  International Association for Probabalistic Safety Assessment & Management (IAPSAM), Mannheim, Germany. 
  • Unwin SD, PP Lowry, and MY Toyooka. 2010. "COMPONENT DEGRADATION SUSCEPTIBILITIES AS THE BASES FOR MODELING REACTOR AGING RISK ." In 2010 Pressure Vessels & Piping Conference (PVP 2010): Pressure Vessel Technology for Energy Challenge, pp. Paper No. PVP2010-25750.  American Society of Mechanical Engineers, New York, NY. 
  • Anderson RM, SD Unwin, and FB Van Cleve. 2010. Identification and Prioritization of Analysis Cases for Marine and Hydrokinetic Energy Risk ScreeningPNNL-19535, Pacific Northwest National Laboratory, Richland, WA. 
  • Anderson RM, AE Copping, FB Van Cleve, SD Unwin, and EL Hamilton. 2010. Conceptual Model of Offshore Wind Environmental Risk Evaluation SystemPNNL-19500, Pacific Northwest National Laboratory, Richland, WA. 
  • Sanfilippo AP, RM Riensche, SD Unwin, and JP Amaya. 2010. "Bridging the Gap between Human Judgment and Automated Reasoning in Predictive Analytics." In 10th International Probabilistic Safety Assessment & Management Conference - PSAM10, June 7-11, 2010, Seattle, WA.  International Association for Probabilistic Safety Assessment & Management, Mannheim, Germany. 

2009

  • Unwin SD, and BA Fecht. 2009. "Consumer Choice and Dempster-Shafer Models of Threat Prioritization for Emerging Dual-Use Technologies: Their Application to Synthetic Biology." Defense & Security Analysis 25(1):37-52. 
  • Unwin SD, PP Lowry, and MY Toyooka. 2009. "Informing Reactor Aging Management by Extended Risk Methodology ." Transactions of the American Nuclear Society 101(1):1047-1048. 
  • Riensche RM, PR Paulson, GR Danielson, SD Unwin, RS Butner, SM Miller, L Franklin, and N Zuljevic. 2009. "Serious Gaming for Predictive Analytics." In AAAI Spring Symposium on Technosocial Predictive Analytics.  Association for the Advancement of Artificial Intelligence (AAAI), Menlo Park, CA. 
  • Sanfilippo AP, AJ Cowell, EL Malone, RM Riensche, JJ Thomas, SD Unwin, PD Whitney, and PC Wong. 2009. "Technosocial Predictive Analytics in Support of Naturalistic Decision Making." In NDM9: Proceedings of the Ninth International Conference on Naturalistic Decision Making, June 23-26, 2009, London, United Kingdom, ed. BLW Wong.  British Computer Society, Swindon, United Kingdom. 
  • Unwin SD, and TE Seiple. 2009. Risk D&D Rapid Prototype: Scenario Documentation and Analysis ToolPNNL-18446, Pacific Northwest National Laboratory, Richland, WA. 
  • Wong PC, LYR Leung, N Lu, MJ Scott, PS Mackey, HP Foote, J Correia, Jr, ZT Taylor, J Xu, SD Unwin, and AP Sanfilippo. 2009. "Designing a Collaborative Visual Analytics Tool for Social and Technological Change Prediction." IEEE Computer Graphics and Applications 29(5):58-68.  doi:10.1109/MCG.2009.92
  • Wong PC, LYR Leung, N Lu, ML Paget, J Correia, Jr, W Jiang, PS Mackey, ZT Taylor, YL Xie, J Xu, SD Unwin, and AP Sanfilippo. 2009. "Predicting the Impact of Climate Change on U.S. Power Grids and Its Wider Implications on National Security." In AAAI Spring Symposium on Technosocial Predictive Analytics, vol. SS-09-09, pp. 148-153.  AAAI Press, Menlo Park, CA. 

2008

  • Unwin SD, BA Fecht, and TM Bergsman. 2008. "Business Metrics of Laboratory Space Utilization." Facilities 26(9/10):366-373. 

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