282 research outputs found
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Applicability of Nonproliferation Tools and Concepts to Future Arms Control
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Integrated Global Nuclear Materials Management Preliminary Concepts
The world is at a turning point, moving away from the Cold War nuclear legacy towards a future global nuclear enterprise; and this presents a transformational challenge for nuclear materials management. Achieving safety and security during this transition is complicated by the diversified spectrum of threat 'players' that has greatly impacted nonproliferation, counterterrorism, and homeland security requirements. Rogue states and non-state actors no longer need self-contained national nuclear expertise, materials, and equipment due to availability from various sources in the nuclear market, thereby reducing the time, effort and cost for acquiring a nuclear weapon (i.e., manifestations of latency). The terrorist threat has changed the nature of military and national security requirements to protect these materials. An Integrated Global Nuclear Materials Management (IGNMM) approach would address the existing legacy nuclear materials and the evolution towards a nuclear energy future, while strengthening a regime to prevent nuclear weapon proliferation. In this paper, some preliminary concepts and studies of IGNMM will be presented. A systematic analysis of nuclear materials, activities, and controls can lead to a tractable, integrated global nuclear materials management architecture that can help remediate the past and manage the future. A systems approach is best suited to achieve multi-dimensional and interdependent solutions, including comprehensive, end-to-end capabilities; coordinated diverse elements for enhanced functionality with economy; and translation of goals/objectives or standards into locally optimized solutions. A risk-informed basis is excellent for evaluating system alternatives and performances, and it is especially appropriate for the security arena. Risk management strategies--such as defense-in-depth, diversity, and control quality--help to weave together various technologies and practices into a strong and robust security fabric. Effective policy, science/technology, and intelligence elements are all crucial and must be harmonized. It is envisioned that integrated solutions will include reducing and securing nuclear/radiological materials at their source; improved monitoring and tracking; and enhancing detection, interdiction, and response. An active architecture, artfully combined of many synergistic elements, would support national actions and international collaboration in nuclear materials management, and it would help navigate a transition toward global nuclear sustainability
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Integrated Global Nuclear Materials Management - Preliminary Concepts -
Approach to Connect Global Objectives and Local Actions: (1) Articulate global objectives into a hierarchy of subsystem requirements and local attributes and measures; (2) Establish a baseline system and viable alternatives through the interactions and relationships (e.g., networks) of local system elements and their options; (3) Evaluate performance of system alternatives and develop improved nuclear material management strategies and technologies; and (4) The need to address greatest concerns first (prioritized or graded approach) and to make tradeoffs among implementation options and competing objectives entails a risk-based approach. IGNMM could provide a systematic understanding of global nuclear materials management and evolutionarily improve and integrate the management through an active architecture, using for example, situation awareness, system models, methods, technologies, and international cooperation. Different tools would be used within the overall framework to address individual issues on the desired geographic scale that could be easily linked to broader analyses. Life-cycle system analyses would allow for evaluating material path alternatives on an integrated global scale. Disconnects, overlaps, technical options, and alternatives for optimizing nuclear materials processes could be evaluated in an integrated manner
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On-line liquid-effluent monitoring of sewage at Lawrence Livermore National Laboratory
LLNL's sanitary sewer system is a possible route for the escape of toxic materials. Liquid effluents are released to Livermore's sanitary sewer system and the effluent is treated at the Livermore Water Reclamation Plant (LWRP). The plant is a secondary-treatment operation that returns most of the water to the San Francisco Bay via a transport pipeline. The remaining portion is used for irrigating vegetation along the roadways and a local golf course. An automatic on-line, sewage-effluent-monitoring system has been developed that diverts a representative fraction of the total waste stream leaving the site. This portion is monitored for pH, radiation, and heavy metals as it passes through a detection assembly. The assembly consists of an industrial pH probe, two NaI radiation detectors, and an x-ray fluorescence metal detector. A microprocessor collects, reduces, and analyzes the data to determine if the levels are acceptable by established environmental limits
Simultaneous solution of Kompaneets equation and Radiative Transfer equation in the photon energy range 1 - 125 KeV
Radiative transfer equation in plane parallel geometry and Kompaneets
equation is solved simultaneously to obtain theoretical spectrum of 1-125 KeV
photon energy range. Diffuse radiation field is calculated using
time-independent radiative transfer equation in plane parallel geometry, which
is developed using discrete space theory (DST) of radiative transfer in a
homogeneous medium for different optical depths. We assumed free-free emission
and absorption and emission due to electron gas to be operating in the medium.
The three terms and where is photon phase density and , in Kompaneets equation and those due to
free-free emission are utilized to calculate the change in the photon phase
density in a hot electron gas. Two types of incident radiation are considered:
(1) isotropic radiation with the modified black body radiation [1] and
(2) anisotropic radiation which is angle dependent. The emergent radiation at
and reflected radiation are calculated by using the
diffuse radiation from the medium. The emergent and reflected radiation contain
the free-free emission and emission from the hot electron gas. Kompaneets
equation gives the changes in photon phase densities in different types of
media. Although the initial spectrum is angle dependent, the Kompaneets
equation gives a spectrum which is angle independent after several Compton
scattering times.Comment: 31 pages, 8 figures, Accepte
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Next Generation Safeguards Initiative Workshop on Enhanced Recruiting for International Safeguards
In 2007, the National Nuclear Security Administration's Office of Nonproliferation and International Security (NA-24) completed a yearlong review of the challenges facing the international safeguards system today and over the next 25 years. The study found that without new investment in international safeguards, the U.S. safeguards technology base, and our ability to support International Atomic Energy Agency (IAEA) safeguards, will continue to erode and soon may be at risk. To reverse this trend, the then U.S. Secretary of Energy, Samuel Bodman, announced at the 2007 IAEA General Conference that the Department of Energy (DOE) would launch the Next Generation Safeguards Initiative (NGSI). He stated 'IAEA safeguards must be robust and capable of addressing proliferation threats. Full confidence in IAEA safeguards is essential for nuclear power to grow safely and securely. To this end, the U.S. Department of Energy will seek to ensure that modern technology, the best scientific expertise, and adequate resources are available to keep pace with expanding IAEA responsibilities.' To meet this goal, the NGSI objectives include the recruitment of international safeguards experts to work at the U.S. national laboratories and to serve at the IAEA's headquarters. Part of the latter effort will involve enhancing our existing efforts to place well-qualified Americans in a sufficient number of key safeguards positions within the IAEA's Department of Safeguards. Accordingly, the International Safeguards Project Office (ISPO) at Brookhaven National Laboratory (BNL) hosted a Workshop on Enhanced Recruiting for International Safeguards (ERIS) on October 22 and 23, 2008. The ISPO used a workshop format developed earlier with Sonalysts, Inc., that was followed at the U.S. Support Program's (USSP's) technology road-mapping sessions. ISPO invited participants from the U.S. DOE, the IAEA, the U.S. national laboratories, private industry, academia, and professional societies who either are experts in international safeguards, or understand the challenges of recruiting for technical positions. The 44 participants represented eight national laboratories, four universities, three government organizations, two international organizations, two professional organizations, and three small companies. The goal of the ERIS workshop was to improve efforts to engage U.S. citizens for IAEA positions in the Department of Safeguards. The participants considered the specific challenges of recruiting professional staff, safeguards inspectors, and managers. At the workshop's conclusion, participants presented their findings to the NNSA Office of International Regimes and Agreements (NA-243). The report's major findings are summarized
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LISSAT Analysis of a Generic Centrifuge Enrichment Plant
The U.S. Department of Energy (DOE) is interested in developing tools and methods for use in designing and evaluating safeguards systems for current and future plants in the nuclear power fuel cycle. The DOE is engaging several DOE National Laboratories in efforts applied to safeguards for chemical conversion plants and gaseous centrifuge enrichment plants. As part of the development, Lawrence Livermore National Laboratory has developed an integrated safeguards system analysis tool (LISSAT). This tool provides modeling and analysis of facility and safeguards operations, generation of diversion paths, and evaluation of safeguards system effectiveness. The constituent elements of diversion scenarios, including material extraction and concealment measures, are structured using directed graphs (digraphs) and fault trees. Statistical analysis evaluates the effectiveness of measurement verification plans and randomly timed inspections. Time domain simulations analyze significant scenarios, especially those involving alternate time ordering of events or issues of timeliness. Such simulations can provide additional information to the fault tree analysis and can help identify the range of normal operations and, by extension, identify additional plant operational signatures of diversions. LISSAT analyses can be used to compare the diversion-detection probabilities for individual safeguards technologies and to inform overall strategy implementations for present and future plants. Additionally, LISSAT can be the basis for a rigorous cost-effectiveness analysis of safeguards and design options. This paper will describe the results of a LISSAT analysis of a generic centrifuge enrichment plant. The paper will describe the diversion scenarios analyzed and the effectiveness of various safeguards systems alternatives
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Advances in nuclear instrumentation for safeguards
This paper describes detectors, instrumentation, and analytical methods under development to address the above issues. The authors will describe work underway on room-temperature semiconductors including attempts to model the response of these detectors to improve spectrum analysis procedures and detector design. Computerized tomography is used in many medical and industrial applications; they are developing both gamma-ray and neutron tomography for improved measurements of waste and direct-use materials. Modern electronics and scintillation detectors should permit the development of fast neutron coincidence detectors with dramatically improved signal-to-noise ratios. For active measurements, they are studying several improved neutron sources, including a high-fluence, plasma-based, d-t generator. New analysis tools from information theory may permit one to better combine data from different measurement systems. This paper attempts to briefly describe a range of new sensors, electronics, and data analysis methods under study at Los Alamos and other laboratories to promote discussion of promising technology that they may bring to bear on these important global issues
Phase 1/2 multiple ascending dose trial of the prostate-specific membrane antigen-targeted antibody drug conjugate MLN2704 in metastatic castration-resistant prostate cancer
This phase 1/2 study evaluated the dose-limiting toxicity and maximum tolerated dose of MLN2704, a humanized monoclonal antibody MLN591 targeting prostate-specific membrane antigen, linked to the maytansinoid DM1 in patients with progressive metastatic castration-resistant prostate cancer
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