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Brothers, Alan J

Publications and source records attributed to Brothers, Alan J.

Model and Analytic Processes for Export License Assessments

This paper represents the Department of Energy Office of Nonproliferation Research and Development (NA-22) Simulations, Algorithms and Modeling (SAM) Program's first effort to identify and frame analytical methods and tools to aid export control professionals in effectively predicting proliferation intent; a complex, multi-step and multi-agency process. The report focuses on analytical modeling methodologies that alone, or combined, may improve the proliferation export control license approval process. It is a follow-up to an earlier paper describing information sources and environments related to international nuclear technology transfer. This report describes the decision criteria used to evaluate modeling techniques and tools to determine which approaches will be investigated during the final 2 years of the project. The report also details the motivation for why new modeling techniques and tools are needed. The analytical modeling methodologies will enable analysts to evaluate the information environment for relevance to detecting proliferation intent, with specific focus on assessing risks associated with transferring dual-use technologies. Dual-use technologies can be used in both weapons and commercial enterprises. A decision-framework was developed to evaluate which of the different analytical modeling methodologies would be most appropriate conditional on the uniqueness of the approach, data availability, laboratory capabilities, relevance to NA-22 and Office of Arms Control and Nonproliferation (NA-24) research needs and the impact if successful. Modeling methodologies were divided into whether they could help micro-level assessments (e.g., help improve individual license assessments) or macro-level assessment. Macro-level assessment focuses on suppliers, technology, consumers, economies, and proliferation context. Macro-level assessment technologies scored higher in the area of uniqueness because less work has been done at the macro level. An approach to developing testable hypotheses for the macro-level assessment methodologies is provided. The outcome of this works suggests that we should develop a Bayes Net for micro-level analysis and continue to focus on Bayes Net, System Dynamics and Economic Input/Output models for assessing macro-level problems. Simultaneously, we need to develop metrics for assessing intent in export control, including the risks and consequences associated with all aspects of export control.

98 NUCLEAR DISARMAMENT, SAFEGUARDS, AND PHYSICAL P↗

SOCIAL MODELING IN ASSESSEMENT OF A STATE’S PROPENSITY FOR NUCLEAR PROLIFERATION

This paper presents approach for assessing a State’s propensity for nuclear weapons proliferation using social modeling. We supported this modeling by first reviewing primarily literature by social scientists on factors related to the propensity of a State to proliferation and by leveraging existing relevant data compiled by social scientists. We performed a number of validation tests on our model including one that incorporates use of benchmark data defining the proliferation status of countries in the years between 1945 and 2000. We exercise the BN model against a number of country cases representing different perceived levels of proliferation risk. We also describe how the BN model could be further refined to be a proliferation assessment tool for decision making.

98 NUCLEAR DISARMAMENT, SAFEGUARDS, AND PHYSICAL P↗

Bayesian Networks for Social Modeling

This paper describes a body of work developed over the past five years. The work addresses the use of Bayesian network (BN) models for representing and predicting social/organizational behaviors. The topics covered include model construction, validation, and use. These topics show the bulk of the lifetime of such model, beginning with construction, moving to validation and other aspects of model ‘critiquing’, and finally demonstrating how the modeling approach might be used to inform policy analysis. To conclude, we discuss limitations of using BN for this activity and suggest remedies to address those limitations. The primary benefits of using a well-developed computational, mathematical, and statistical modeling structure, such as BN, are 1) there are significant computational, theoretical and capability bases on which to build 2) ability to empirically critique the model, and potentially evaluate competing models for a social/behavioral phenomena.

99 GENERAL AND MISCELLANEOUS↗

Low Probability Tail Event Analysis and Mitigation in the BPA Control Area

This report investigated the uncertainties with the operations of the power system and their contributions to tail events, especially under high penetration of wind. A Bayesian network model is established to quantify the impact of these uncertainties on system imbalance. The framework is presented for a decision support tool, which can help system operators better estimate the need for balancing reserves and prepare for tail events.

24 POWER TRANSMISSION AND DISTRIBUTION↗

Expert Elicitation Method Selection Process and Method Comparison

Research on integrative modeling has gained considerable attention in recent years and expert opinion has been increasingly recognized as an important data source and modeling contributor. However, little research has systematically compared and evaluated expert elicitation methods in terms of their ability to link to computational models that capture human behavior and social phenomena. In this paper, we describe a decision-making process we used for evaluating and selecting a task specific elicitation method within the framework of integrative computational social-behavioral modeling. From the existing literature, we identified the characteristics of problems that each candidate method is well suited to address. A small-scale expert elicitation was also conducted to evaluate the comparative strength and weaknesses of the methods against a number of consensus-based decision criteria. By developing a set of explicit method evaluation criteria and a description characterizing decision problems for the candidate methods, we seek to gain a better understanding of the feasibility and cost-effectiveness of integrating elicitation methods with computational modeling techniques. This serves an important first step toward expanding our research effort and trajectory toward greater interdisciplinary modeling research of human behavior.

99 GENERAL AND MISCELLANEOUS↗

AN ANALYTICAL FRAMEWORK FOR ASSESSING RELIABLE NUCLEAR FUEL SERVICE APPROACHES: ECONOMIC AND NON-PROLIFERATION MERITS OF NUCLEAR FUEL LEASING

The goal of international nuclear policy since the dawn of nuclear power has been the peaceful expansion of nuclear energy while controlling the spread of enrichment and reprocessing technology. Numerous initiatives undertaken in the intervening decades to develop international agreements on providing nuclear fuel supply assurances, or reliable nuclear fuel services (RNFS) attempted to control the spread of sensitive nuclear materials and technology. In order to inform the international debate and the development of government policy, PNNL has been developing an analytical framework to holistically evaluate the economics and non-proliferation merits of alternative approaches to managing the nuclear fuel cycle (i.e., cradle-to-grave). This paper provides an overview of the analytical framework and discusses preliminary results of an economic assessment of one RNFS approach: full-service nuclear fuel leasing. The specific focus of this paper is the metrics under development to systematically evaluate the non-proliferation merits of fuel-cycle management alternatives. Also discussed is the utility of an integrated assessment of the economics and non-proliferation merits of nuclear fuel leasing.

11 NUCLEAR FUEL CYCLE AND FUEL MATERIALS↗