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Application of SAFE to an operating reactor

Description: A method for the evaluation of physical protection systems at nuclear facilities has been developed. The evaluation process consists of five major phases: (1) Facility Characterization, (2) Facility Representation, (3) Component Performance, (4) Adversary Path Analysis, and (5) Effectiveness Evaluation. Each of these phases will be described in some detail and illustrated by examples. The process for evaluation of physical protection system effectiveness against an outside threat will be presented for a reactor facility.
Date: January 1, 1979
Creator: Chapman, L.D.
Partner: UNT Libraries Government Documents Department

Physical protection of nuclear facilities. Quarterly progress report, July--September 1978. [PWR; BWR]

Description: Major activities during the fourth quarter of FY78 included (1) the vital area analysis of operational reactors and characterization of the Standardized Nuclear Unit Power Plant System (SNUPPS), (2) the algorithm development of a new pathfinding computer code, (3) the completion of contractor-supported work for the component generic data base, (4) the refinement of tests related to human parameters modeling, and (5) the addition of improvements to and demonstration of the Safeguards Automated Facility Evaluation (SAFE), Safeguards Network Analysis Procedure (SNAP), and Fixed-Site Neutralization Model (FSNM) methodologies.
Date: January 1, 1979
Creator: Chapman, L.D. (ed.)
Partner: UNT Libraries Government Documents Department

Assessment of methods for evaluating adequacy of physical protection systems

Description: Generally, the scope of a safeguards evaluation model can efficiently address one of two issues: (1) global safeguards effectiveness or (2) vulnerability analysis for individual scenarios. A brief description of the variety of models developed in these areas is discussed. Current generation models are described along with an assessment of their utility and a brief look at future techniques for evaluation will be noted.
Date: January 1, 1980
Creator: Chapman, L.D.
Partner: UNT Libraries Government Documents Department

Combined SAFE/SNAP approach to safeguards evaluation. [Safeguards Network Analysis]

Description: Generally, the scope of a safeguards evaluation model can efficiently address one of two issues, (1) global safeguards effectiveness, or (2) vulnerability analysis for individual scenarios. The Safeguards Automated Facility Evaluation (SAFE) focuses on (1) while the Safeguards Network Analysis Procedure (SNAP) is directed at (2). SAFE addresses (1) in that it considers the entire facility, i.e., the composite system of hardware and human components, in one global analysis. SNAP addresses (2) by providing a safeguards modeling symbology sufficiently flexible to represent quite complex scenarios from the standpoint of hardware interfaces while also accounting for a rich variety of human decision making. A combined SAFE/SNAP approach to the problem of safeguards evaluation is described and illustrated through an example.
Date: January 1, 1980
Creator: Engi, D.; Chapman, L.D.; Grant, F.H. & Polito, J.
Partner: UNT Libraries Government Documents Department

Fixed site neutralization model programmer's manual. Volume II

Description: This report relates to protection of nuclear materials at nuclear facilities. This volume presents the source listings for the Fixed Site Neutralization Model and its supporting modules, the Plex Preprocessor and the Data Preprocessor. (DLC)
Date: December 1, 1979
Creator: Engi, D.; Chapman, L.D.; Judnick, W.; Blum, R.; Broegler, L.; Lenz, J. et al.
Partner: UNT Libraries Government Documents Department

Safeguards methodology development history

Description: The development of models for the evaluation and design of fixed-site nuclear facility, physical protection systems was under way in 1974 at Sandia Laboratories and has continued to the present. A history of the evolution of these models and the model descriptions are presented. Several models have been and are continuing to be applied to evaluate and design facility protection systems.
Date: January 1, 1979
Creator: Chapman, L.D.; Bennett, H.A.; Engi, D.; Grady, L.M.; Hulme, B.L. & Sasser, D.W.
Partner: UNT Libraries Government Documents Department

Multiple energy computed tomography with monochromatic x rays from the NSLS

Description: We used monochromatic x rays from the X17 superconducting wiggler beamline at the National Synchrotron Light Source (NSLS), Brookhaven National Laboratory, for dual-energy quantitative computed tomography (CT) of a 27 mm-diameter phantom containing solutions of different KOH concentrations in cylindrical holes of 5-mm diameter. The CT configuration was a fixed horizontal fan-shaped beam of 1.5 mm height and 30 mm width, and a subject rotating around a vertical axis. The transmitted x rays were detected by a linear-array Si(Li) detector with 120 elements of 0.25 mm width each. We used a two-crystal Bragg-Bragg fixed-exit monochromator with Si<220> crystals. Dual photon absorptiometry (DPA) CT data were taken at 20 and 38 keV. The reconstructed phantom images show the potential of the system for quantitative CT.
Date: December 31, 1991
Creator: Dilmanian, F. A.; Nachaliel, E.; Garrett, R. F.; Thomlinson, W. C.; Chapman, L. D.; Moulin, H. R. et al.
Partner: UNT Libraries Government Documents Department

Multiple energy computed tomography with monochromatic x rays from the NSLS

Description: We used monochromatic x rays from the X17 superconducting wiggler beamline at the National Synchrotron Light Source (NSLS), Brookhaven National Laboratory, for dual-energy quantitative computed tomography (CT) of a 27 mm-diameter phantom containing solutions of different KOH concentrations in cylindrical holes of 5-mm diameter. The CT configuration was a fixed horizontal fan-shaped beam of 1.5 mm height and 30 mm width, and a subject rotating around a vertical axis. The transmitted x rays were detected by a linear-array Si(Li) detector with 120 elements of 0.25 mm width each. We used a two-crystal Bragg-Bragg fixed-exit monochromator with Si<220> crystals. Dual photon absorptiometry (DPA) CT data were taken at 20 and 38 keV. The reconstructed phantom images show the potential of the system for quantitative CT.
Date: January 1, 1991
Creator: Dilmanian, F.A.; Nachaliel, E.; Garrett, R.F.; Thomlinson, W.C.; Chapman, L.D.; Moulin, H.R. et al.
Partner: UNT Libraries Government Documents Department

Monochromatic computed tomography of the human brain using synchrotron x rays: Technical feasibility

Description: A monochromatic computed tomography (CT) scanner is being developed at the X17 superconducting wiggler beamline at the National Synchrotron Light Source (NSLS), Brookhaven National Laboratory, to image the human head and neck. The system configuration is one of a horizontal fan beam and an upright seated rotating subject. The purpose of the project are to demonstrate improvement in the image contrast and in the image quantitative accuracy that can be obtained in monochromatic CT and to apply the system to specific clinical research programs in neuroradiology. This paper describes the first phantom studies carried out with a prototype system, using the dual photon absorptiometry (DPA) method at energies of 20 and 39 Kev. The results show that improvements in image contrast and quantitative accuracy are possible with monochromatic DPA CT. Estimates of the clinical performance of the planned CT system are made on the basis of these initial results.
Date: December 31, 1991
Creator: Nachaliel, E.; Dilmanian, F. A.; Garrett, R. F.; Thomlinson, W. C.; Chapman, L. D.; Gmuer, N. F. et al.
Partner: UNT Libraries Government Documents Department

Monochromatic computed tomography of the human brain using synchrotron x rays: Technical feasibility

Description: A monochromatic computed tomography (CT) scanner is being developed at the X17 superconducting wiggler beamline at the National Synchrotron Light Source (NSLS), Brookhaven National Laboratory, to image the human head and neck. The system configuration is one of a horizontal fan beam and an upright seated rotating subject. The purpose of the project are to demonstrate improvement in the image contrast and in the image quantitative accuracy that can be obtained in monochromatic CT and to apply the system to specific clinical research programs in neuroradiology. This paper describes the first phantom studies carried out with a prototype system, using the dual photon absorptiometry (DPA) method at energies of 20 and 39 Kev. The results show that improvements in image contrast and quantitative accuracy are possible with monochromatic DPA CT. Estimates of the clinical performance of the planned CT system are made on the basis of these initial results.
Date: January 1, 1991
Creator: Nachaliel, E.; Dilmanian, F.A.; Garrett, R.F.; Thomlinson, W.C.; Chapman, L.D.; Gmuer, N.F. et al.
Partner: UNT Libraries Government Documents Department

CT imaging of small animals using monochromatized synchrotron x rays

Description: Rats and chicken embryos were imaged in vivo with a prototype Multiple Energy Computed Tomography (MECT) system using monochromatized x rays from the X17 superconducting wiggler at the National Synchrotron Light Source. The CT configuration coated of a horizontal low-divergence, fan-shaped beam, 70 mm wide and 0.5 mm high, and a subject rotating about a vertical aids. A linear-array high-purity Ge detector with 140 elements, each 0.5 mm wide and 6 mm thick, was used with a data acquisition system that provides a linear response over almost six orders of magnitude of detector current. The dual photon absorptiometry (DPA) algorithm was applied to images of the rat head acquired at 20 and 45 keV to obtain two new images, one representing the low-Z, and the other the intermediate-Z clement group. The results indicate that the contrast resolution and the quantification accuracy of the images improve stepwise; first, with the monochromatic beam and, second, the DPA method. The system is a prototype for a brain scanner.
Date: January 1, 1992
Creator: Dilmanian, F.A.; Rarback, H.; Nachaliel, E.; Rivers, M.; Thomlinson, W.C.; Chapman, L.D. et al.
Partner: UNT Libraries Government Documents Department