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Overview of the structured assessment approach and documentation of algorithms to compute the probability of adversary detection

Description: The Structured Assessment Approach was applied to material control and accounting systems at facilities that process Special Nuclear Material. Four groups of analytical techniques were developed for four general adversory types. Probabilistic algorithms were developed and compared with existing algorithms. 20 figures. (DLC)
Date: December 15, 1978
Creator: Rice, T.R. & Derby, S.L.
Partner: UNT Libraries Government Documents Department

Energy conservation standards for new federal residential buildings: A decision analysis study using relative value discounting

Description: This report presents a reassessment of the proposed standard for energy conservation in new federal residential buildings. The analysis uses the data presented in the report, Economic Analysis: In Support of Interim Energy Conservation Standards for New Federal Residential Buildings (June 1988)-to be referred to as the EASIECS report. The reassessment differs from that report in several respects. In modeling factual information, it uses more recent forecasts of future energy prices and it uses data from the Bureau of the Census in order to estimate the distribution of lifetimes of residential buildings rather than assuming a hypothetical 25-year lifetime. In modeling social preferences decision analysis techniques are used in order to examine issues of public values that often are not included in traditional cost-benefit analyses. The present report concludes that the public would benefit from the proposed standard. Several issues of public values regarding energy use are illustrated with methods to include them in a formal analysis of a proposed energy policy. The first issue places a value on costs and benefits that will occur in the future as an irreversible consequence of current policy choices. This report discusses an alternative method, called relative value discounting which permits flexible discounting of future events-and the possibility of placing greater values on future events. The second issue places a value on the indirect benefits of energy savings so that benefits accrue to everyone rather than only to the person who saves the energy. This report includes non-zero estimates of the indirect benefits. The third issue is how the costs and benefits discussed in a public policy evaluation should be compared. In summary, selection of individual projects with larger benefit to cost ratios leads to a portfolio of projects with the maximum benefit to cost difference. 30 refs., 6 figs., 16 tabs. (JF)
Date: July 2, 1990
Creator: Harvey, C. (Houston Univ., TX (USA). Coll. of Business Administration); Merkhofer, M.M. & Hamm, G.L. (Applied Decision Analysis, Inc., Menlo Park, CA (USA))
Partner: UNT Libraries Government Documents Department

Definition, development, and demonstration of analytical procedures for the structured assessment approach. Final report

Description: Analytical procedures were refined for the Structural Assessment Approach for assessing the Material Control and Accounting systems at facilities that contain special nuclear material. Requirements were established for an efficient, feasible algorithm to be used in evaluating system performance measures that involve the probability of detection. Algorithm requirements to calculate the probability of detection for a given type of adversary and the target set are described.
Date: April 15, 1979
Partner: UNT Libraries Government Documents Department

Methodology and preliminary models for analyzing nuclear safeguards decisions

Description: This report describes a general analytical tool designed to assist the NRC in making nuclear safeguards decisions. The approach is based on decision analysis--a quantitative procedure for making decisions under uncertain conditions. The report: describes illustrative models that quantify the probability and consequences of diverted special nuclear material and the costs of safeguarding the material, demonstrates a methodology for using this information to set safeguards regulations (safeguards criteria), and summarizes insights gained in a very preliminary assessment of a hypothetical reprocessing plant.
Date: November 1, 1978
Partner: UNT Libraries Government Documents Department

Aggregated systems model for nuclear safeguards decisions

Description: This report summarizes a general analytical tool designed to assist nuclear safeguards decision-makers. The approach is based on decision analysis--a quantitative procedure for evaluating complex decision alternatives with uncertain outcomes. The report describes the general analytical approach in the context of safeguards decisions at a hypothetical nuclear fuel reprocessing plant.
Date: March 1, 1979
Partner: UNT Libraries Government Documents Department

Framework for evaluating the effectiveness of nuclear-safeguards systems. [Aggregated Systems Model (ASM)]

Description: This paper describes an analytical tool for evaluating the effectiveness of safeguards that protect special nuclear material (SNM). The tool quantifies the effectiveness using several measures, including probabilities and expected times to detect and respond to malevolent attempts against the facility. These measures are computed for a spectrum of threats involving outsiders, insiders, collusion, falsification, and deceit. Overall system effectiveness is judged using performance indices aggregated over all threats. These indices can be used by designers and regulators when comparing costs and benefits of various safeguards. The framework is demonstrated with an example in which we assess vulnerabilities of a safeguards system and identify cost-effective design modifications.
Date: October 20, 1981
Creator: Al-Ayat, R.A. & Judd, B.R.
Partner: UNT Libraries Government Documents Department

Framework for analyzing safeguards alarms and response decisions

Description: This paper describes a quantitative approach to help evaluate and respond to safeguards alarms. These alrms may be generated internally by a facility's safeguards systems or externally by individuals claiming to possess stolen Special Nuclear Material (SNM). This approach can be used to identify the most likely cause of an alarm - theft, hoax, or error - and to evaluate alternative responses to alarms. Possible responses include conducting investigations, initiating measures to recover stolen SNM, and replying to external threats. Based on the results of each alarm investigation step, the evaluation revises the likelihoods of possible causes of an alarm, and uses this information to determine the optimal sequence of further responses. The choice of an optimal sequence of responses takes into consideration the costs and benefits of successful thefts or hoaxes. These results provide an analytical basis for setting priorities and developing contingency plans for responding to safeguards alarms.
Date: June 11, 1982
Creator: Al-Ayat, R.A.; Judd, B.R. & McCord, R.K.
Partner: UNT Libraries Government Documents Department

Aggregated systems model: a tool for nuclear safeguards decision-making

Description: Setting performance criteria for systems that safeguard special nuclear material (SNM) involves many considerations: characteristics of adversaries attempting to divert SNM, safeguards response to attempts, costs of safeguards systems, and the consequences of diverted SNM. This paper describes an Aggregated Systems Model which is designed to assist decision makers integrate and evaluate consistently these diverse factors. Results from applying the model to a hypothetical facility handling SNM are summarized. The paper also describes a new performance criterion designed to measure the effectiveness of a safeguard system in deterring adversaries.
Date: October 4, 1979
Creator: Al-Ayat, R.; Judd, B. & Huntsman, J.
Partner: UNT Libraries Government Documents Department

Evaluating alternative responses to safeguards alarms

Description: This paper describes a quantitative approach to help evaluate and respond to safeguards alarms. These alarms may be generated internally by a facility's safeguards systems or externally by individuals claiming to have stolen special nuclear material (SNM). This approach can be used to identify the most likely cause of an alarm - theft, hoax, or error - and to evaluate alternative responses to alarms. Possible responses include conducting investigations, initiating measures to recover stolen SNM, and replying to external threats. Based on the results of each alarm investigation step, the evaluation revises the likelihoods of possible causes of an alarm, and uses this information to determine the optimal sequence of further responses. The choice of an optimal sequence of responses takes into consideration the costs and benefits of successful thefts or hoaxes. These results provide an analytical basis for setting priorities and developing contingency plans for responding to safeguards alarms.
Date: April 15, 1982
Creator: Al-Ayat, R.A.; Judd, B.R. & McCord, R.K.
Partner: UNT Libraries Government Documents Department

Methodology and preliminary models for analyzing nuclear-safeguards decisions

Description: This report describes a general analytical tool designed with Lawrence Livermore Laboratory to assist the Nuclear Regulatory Commission in making nuclear safeguards decisions. The approach is based on decision analysis - a quantitative procedure for making decisions under uncertain conditions. The report: describes illustrative models that quantify the probability and consequences of diverted special nuclear material and the costs of safeguarding the material; demonstrates a methodology for using this information to set safeguards regulations (safeguards criteria); and summarizes insights gained in a very preliminary assessment of a hypothetical reprocessing plant.
Date: November 1, 1978
Creator: Judd, B.R. & Weissenberger, S.
Partner: UNT Libraries Government Documents Department

Probability encoding of hydrologic parameters for basalt. Elicitation of expert opinions from a panel of three basalt waste isolation project staff hydrologists

Description: The present study implemented a probability encoding method to estimate the probability distributions of selected hydrologic variables for the Cohassett basalt flow top and flow interior, and the anisotropy ratio of the interior of the Cohassett basalt flow beneath the Hanford Site. Site-speciic data for these hydrologic parameters are currently inadequate for the purpose of preliminary assessment of candidate repository performance. However, this information is required to complete preliminary performance assessment studies. Rockwell chose a probability encoding method developed by SRI International to generate credible and auditable estimates of the probability distributions of effective porosity and hydraulic conductivity anisotropy. The results indicate significant differences of opinion among the experts. This was especially true of the values of the effective porosity of the Cohassett basalt flow interior for which estimates differ by more than five orders of magnitude. The experts are in greater agreement about the values of effective porosity of the Cohassett basalt flow top; their estimates for this variable are generally within one to two orders of magnitiude of each other. For anisotropy ratio, the expert estimates are generally within two or three orders of magnitude of each other. Based on this study, the Rockwell hydrologists estimate the effective porosity of the Cohassett basalt flow top to be generally higher than do the independent experts. For the effective porosity of the Cohassett basalt flow top, the estimates of the Rockwell hydrologists indicate a smaller uncertainty than do the estimates of the independent experts. On the other hand, for the effective porosity and anisotropy ratio of the Cohassett basalt flow interior, the estimates of the Rockwell hydrologists indicate a larger uncertainty than do the estimates of the independent experts.
Date: November 1, 1984
Creator: Runchal, A.K.; Merkhofer, M.W.; Olmsted, E. & Davis, J.D.
Partner: UNT Libraries Government Documents Department

Probability encoding of hydrologic parameters for basalt. Elicitation of expert opinions from a panel of five consulting hydrologists

Description: The Columbia River basalts underlying the Hanford Site in Washington State are being considered as a possible location for a geologic repository for high-level nuclear waste. To investigate the feasibility of a repository at this site, the hydrologic parameters of the site must be evaluated. Among hydrologic parameters of particular interest are the effective porosity of the Cohassett basalt flow top and flow interior and the vertical-to-horizontal hydraulic conductivity, or anisotropy ratio, of the Cohassett basalt flow interior. The Cohassett basalt flow is the prime candidate horizon for repository studies. Site-specific data for these hydrologic parameters are currently inadequate for the purpose of preliminary assessment of candidate repository performance. To obtain credible, auditable, and independently derived estimates of the specified hydrologic parameters, a panel of five nationally recognized hydrologists was assembled. Their expert judgments were quantified during two rounds of Delphi process by means of a probability encoding method developed to estimate the probability distributions of the selected hydrologic variables. The results indicate significant differences of expert opinion for cumulative probabilities of less than 10% and greater than 90%, but relatively close agreement in the middle ranges of values. The principal causes of the diversity of opinion are believed to be the lack of site-specific data and the absence of a single, widely accepted, conceptual or theoretical basis for analyzing these variables.
Date: November 1, 1984
Creator: Runchal, A.K.; Merkhofer, M.W.; Olmsted, E. & Davis, J.D.
Partner: UNT Libraries Government Documents Department