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Taxonomy of potential international safeguards regimes (open access)

Taxonomy of potential international safeguards regimes

Since the International Atomic Energy Agency`s (IAEA) search for the components of Iraq`s nuclear weapons program under the auspices of the United Nations Security Council, a consensus for enhancing, strengthening or expanding the scope of international safeguards has developed. Some of the enhanced safeguards concepts which have been suggested include the following: short-notice, challenge, and random inspections; effluent monitoring in onsite, near site, and fly-by modes; local and wide-area environmental monitoring; and utilization of data from space-platform sensors. Potential safeguards regimes can be classified according to the functional and technical criteria which would be necessary for implementation of various enhanced safeguards concepts. While the nature of the regime which will emerge cannot be predicted, the classification of possible regimes according to major characteristics can be useful for identifying functional criteria and implementation challenges, focusing development efforts on the functional criteria, and planning for efficient use of safeguards resources. Precedents established in previously negotiated treaties -- the Chemical Weapons Convention, the Treaty on Conventional Forces in Europe, START, and Open Skies -- are examined with regard to enhancement of the international safeguards regime for nuclear and other weapons of mass destruction. Bilateral, multilateral and regional integration of enhanced safeguards elements is …
Date: August 1, 1994
Creator: Lemley, J. R. & Allentuck, J.
System: The UNT Digital Library
Deep levels in AgGaSe{sub 2} (open access)

Deep levels in AgGaSe{sub 2}

The photoluminescence spectra of AgGaSe{sub 2} obtained at 77 K is reported. Two emission peaks have been observed and their pressure dependence studied. One of these peaks has been identified with emission involving one of the two deep level peak D{sub 1} and D{sub 2} observed previously in absorption measurement [App. Phys. Lett. 64,1717 (1994)]. A simple model for the capture of carriers into these deep levels has been proposed.
Date: August 1, 1994
Creator: Choi, I. H. & Yu, P. Y.
System: The UNT Digital Library
The FORTE Receiver and Sub-Band Triggering Unit (open access)

The FORTE Receiver and Sub-Band Triggering Unit

The FORTE payload receiver and trigger unit represent a significant advance over the currently flying BLACKBEARD payload aboard the ALEXIS satellite. Not only is the polarization sensitive antenna array massive compared to the BLACKBEARD monopole, but the event triggering scheme is completely different. Electromagnetic pulses (EWs) are dispersed when they pass through the ionosphere creating a chirped frequency signal which can be helpful in discriminating between natural and man-made signals. Payloads designed to digitize and store the RF signatures of these signals must include sophisticated triggering circuitry to select events of interest and prevent false alarms from wasting the available memory storage resources. The FORTE wideband receiver tunes from 20 to 320 MHz with eight sub-band trigger channels distributed across the 20 MHz IF bandwidth. The conditions which must be satisfied to generate an event trigger are processor controlled. Early testing of the prototype indicates an ability to reliably trigger on chirped RF signals several dB below the noise level. FORTE is scheduled to be launched with a Pegasus XL vehicle in late 1995.
Date: August 1, 1994
Creator: Enemark, Donald C. & Shipley, Martin E.
System: The UNT Digital Library
Insider protection technology developments (open access)

Insider protection technology developments

Sandia National Laboratories evaluates and develops new techniques and technologies to ensure the integrity of special nuclear material (SNM) against potential insider threats. We have evaluated several types of sensor technologies and subsystems to monitor and/or track materials and personnel. This past year`s effort has been directed at characterizing commercial developments that meet the Department of Energy`s (DOE) needs in some of these areas. Some of these evaluations are complete and some are still in progress. This paper discusses our work with infrared light (IR), radio frequency (RF), and RF proximity technologies. After these technologies are judged to be applicable to DOE`s needs, we incorporate them into the generic, real time, personnel tracking and material monitoring system.
Date: August 1, 1994
Creator: Foesch, J.; Bortniak, P. & Waddoups, I.
System: The UNT Digital Library
Dense Feature Maps for Detection of Calcifications (open access)

Dense Feature Maps for Detection of Calcifications

None
Date: August 1, 1994
Creator: Kegelmeyer, W. P. Jr. & Allmen, M. C.
System: The UNT Digital Library
Managed Access by Controlled Sensing (MACS) (open access)

Managed Access by Controlled Sensing (MACS)

During chemical weapons challenge inspections, the CWC treaty allows ``alternate means`` of access to be proposed by the nation challenged. BNL`s Safeguards, Safety and Nonproliferation Division is funded by the Defense Nuclear Agency to develop a system to provide the challenge inspection team with a ``virtual presence`` within the facility while denying personal access. A general purpose configuration of a mobile station manned by site personnel and a base station manned by the challenge inspector, supported by a flexible communication system, will allow facility personnel to tailor the basic model to their site. Design of the MACS system is based on maximum use of commercial equipment that is available on the international market. Design requirements for the MACS system include methods of establishing geographical position, distance measuring equipment for use in verifying dimensions on floor plans, video and two-way audio links between the mobile unit and the base station, and portability and versatility of the equipment. The MACS platform will also support deployment of selected instrumentation which the site may offer to the challenge inspection team. This paper describes the design and construction of the prototype MACS system.
Date: August 1, 1994
Creator: Curtiss, J. A. & Indusi, J. P.
System: The UNT Digital Library
Development of an integrated, unattended assay system for LWR-MOX fuel pellet trays (open access)

Development of an integrated, unattended assay system for LWR-MOX fuel pellet trays

Four identical unattended plutonium assay systems have been developed for use at the new light-water-reactor mixed oxide (LWR-MOX) fuel fabrication facility at Hanau, Germany. The systems provide quantitative plutonium verification for all MOX pellet trays entering or leaving a large, intermediate store. Pellet-tray transport and storage systems are highly automated. Data from the ``I-Point`` (information point) assay systems will be shared by the Euratom and International Atomic Energy Agency (IAEA) Inspectorates. The I-Point system integrates, for the first time, passive neutron coincidence counting (NCC) with electro-mechanical sensing (EMS) in unattended mode. Also, provisions have been made for adding high-resolution gamma spectroscopy. The system accumulates data for every tray entering or leaving the store between inspector visits. During an inspection, data are analyzed and compared with operator declarations for the previous inspection period, nominally one month. Specification of the I-point system resulted from a collaboration between the IAEA, Euratom, Siemens, and Los Alamos. Hardware was developed by Siemens and Los Alamos through a bilateral agreement between the German Federal Ministry of Research and Technology (BMFT) and the US DOE. Siemens also provided the EMS subsystem, including software. Through the USSupport Program to the IAEA, Los Alamos developed the NCC software (NCC …
Date: August 1, 1994
Creator: Stewart, J. E.; Hatcher, C. R. & Pollat, L. L.
System: The UNT Digital Library
Defense Programs Transportation Risk Assessment (open access)

Defense Programs Transportation Risk Assessment

This paper provides an overview of the methodology used in a probabilistic transportation risk assessment conducted to assess the probabilities and consequences of inadvertent dispersal of radioactive materials arising from severe transportation accidents. The model was developed for the Defense Program Transportation Risk Assessment (DPTRA) study. The analysis incorporates several enhancements relative to previous risk assessments of hazardous materials transportation including newly-developed statistics on the frequencies and severities of tractor semitrailer accidents and detailed route characterization using the 1990 Census data.
Date: August 1, 1994
Creator: Clauss, D. B.
System: The UNT Digital Library
The US Department of Energy PFBC perspective, 1994 update (open access)

The US Department of Energy PFBC perspective, 1994 update

Significant progress in the development and commercialization of pressurized fluidized-bed combustion (PFBC) technology has occurred since the 1992 Fluidized-Bed Combustion (FBC) Conference. The US Department of Energy (DOE) has been and continues to be an active partner in most of these activities. This paper presents the 1994 status of DOE activities and a discussion of the importance DOE places on the development and commercialization of PFBC systems. Specifically, this paper discusses the status and focus of DOE activities. Currently, first-generation PFBC systems are on the brink of commercial deployment. The DOE Clean Coal Technology (CCT) Program is assisting in this process by funding demonstration programs to validate that PFBC technologies are a low-risk, environmentally-attractive, cost-competitive option for utility and industrial users. A brief discussion of the scope and the status of major demonstrations are presented. This paper also presents a snapshot of the PFBC development activities that are part of the DOE Research and Development (R&D) Program, i.e., hot gas particulate removal systems and pilot-plant facilities in support of advanced PFBC combined-cycle systems. The R&D pilot plant activities discussed include advanced component development tests at the Foster Wheeler Development Facility and the status of the fully integrated advanced PFBC being …
Date: August 1, 1994
Creator: Carpenter, L. K. & Dellefield, R. J.
System: The UNT Digital Library
Relational databases for RHIC design and control (open access)

Relational databases for RHIC design and control

The preliminary organization of data via relational databases for the design and control of the Relativistic Heavy Ion Collider (RHIC) is described.
Date: August 1, 1994
Creator: Trahern, C. G.; Saltmarsh, C. & Satogata, T.
System: The UNT Digital Library
Photoluminescence determination of valence-band symmetry and Auger-1 threshold energy in biaxially compressed InAsSb layers (open access)

Photoluminescence determination of valence-band symmetry and Auger-1 threshold energy in biaxially compressed InAsSb layers

InAsSb/InGaAs strained-layer superlattices (SLSs) and InAsSb quantum wells, both with biaxially compressed InAsSb layers, were characterized using magneto-photoluminescence and compared with unstained InAsSb and InAs alloys. In heterostructures with biaxially compressed InAsSb, the holes exhibited a decrease in effective mass, approaching that of the electrons. Correcting the data for the magneto-exciton binding energy, we obtain electron-hole reduced mass values in the range, {mu}=0.010--0.015, for the InAsSb heterostructures, whereas {mu}=0.026 and {mu}-0.023 for unstrained InAsSb and InAs alloys respectively. In the 2-dimensional limit, a large increase in the Auger-1 threshold energy accompanies this strain-induced change in valence-band symmetry. Correspondingly, the activation energy for nonradiative recombination in the SLSs displayed a marked increase compared with that of the unstrained alloys.
Date: August 1, 1994
Creator: Kurtz, S. R.; Biefeld, R. M. & Dawson, L. R.
System: The UNT Digital Library
Pitting corrosion of aluminized seals in molten carbonate fuel cells (open access)

Pitting corrosion of aluminized seals in molten carbonate fuel cells

The objective of this research is to gain a better understanding of the corrosion of the aluminized type 316 stainless steel employed in the seal areas of the molten carbonate fuel cell. The seals are formed between the aluminized Type 316 SS surface and the electrolyte (generally a mixture of molten alkali carbonates and lithium aluminate).
Date: August 1, 1994
Creator: Krumpelt, M.; Roche, M. F. & Bloom, I.
System: The UNT Digital Library
Scintillation Mechanism and Radiation Damage in Ce{sub X}La{sub 1-X}F{sub 3} Crystals (open access)

Scintillation Mechanism and Radiation Damage in Ce{sub X}La{sub 1-X}F{sub 3} Crystals

Recent spectroscopic and radiation damage experiments on a series of Ce{sub x}La{sub 1{minus}x}F{sub 3} crystals suggest that the scintillation light output is limited by an unusual quenching mechanism, which also plays a major role in minimizing radiation-induced damage. The intensity of the radiation-induced absorptions is a strong function of the Ce content x, reaching a maximum for x = 0.03 and a minimum for x = 1. This peculiar dependence appears to be due to the influence of deep-lying Ce levels on both scintillation mechanism and radiation damage. The authors suggest that various charge transfer processes can explain many aspects of the performance of Ce{sub x}La{sub 1{minus}x}F{sub 3} scintillators.
Date: August 1, 1994
Creator: Wojtowicz, A. J.; Wisniewski, D.; Lempicki, A.; Brecher, C.; Bartram, R. H.; Woody, C. et al.
System: The UNT Digital Library
Technologies using accelerator-driven targets under development at BNL (open access)

Technologies using accelerator-driven targets under development at BNL

Recent development work conducted at Brookhaven National Laboratory on technologies which use particle accelerator-driven targets is summarized. These efforts include development of the Spallation-Induced Lithium Conversion (SILC) Target for the Accelerator Production of Tritium (APT), the Accelerator-Driven Assembly for Plutonium Transformation (ADAPT) Target for the Accelerator-Based Conversion (ABC) of excess weapons plutonium. The PHOENIX Concept for the accelerator-driven transmutation of minor actinides and fission products from the waste stream of commercial nuclear power plants, and other potential applications.
Date: August 1, 1994
Creator: Van Tuyle, G. J.
System: The UNT Digital Library
Robust lateral control of highway vehicles (open access)

Robust lateral control of highway vehicles

Vehicle lateral dynamics are affected by vehicle mass, longitudinal velocity, vehicle inertia, and the cornering stiffness of the tires. All of these parameters are subject to variation, even over the course of a single trip. Therefore, a practical lateral control system must guarantee stability, and hopefully ride comfort, over a wide range of parameter changes. This paper describes a robust controller which theoretically guarantees stability over a wide range of parameter changes. The robust controller is designed using a frequency domain transfer function approach. An uncertainty band in the frequency domain is determined using simulations over the range of expected parameter variations. Based on this bound, a robust controller is designed by solving the Nevanlinna-Pick interpolation problem. The performance of the robust controller is then evaluated over the range of parameter variations through simulations.
Date: August 1, 1994
Creator: Byrne, R. H. & Abdallah, C.
System: The UNT Digital Library
24th Annual Anomalous Absorption Conference. Book of Abstracts (open access)

24th Annual Anomalous Absorption Conference. Book of Abstracts

This report contains abstracts on topics in the following areas: parametric instabilities; hohlraum physics; laser plasma physics with short pulses; and rayleigh-taylor instability and hydrodynamics.
Date: August 1, 1994
Creator: unknown
System: The UNT Digital Library
Point-source calibration of a segmented gamma-ray scanner (open access)

Point-source calibration of a segmented gamma-ray scanner

For a conventional segmented gamma-ray scanner (SGS) in which the sample is rotated continuously within a fixed detector field of view, the data will not support alternatives to the assumption that the gamma-emitting nuclides and the matrix in which they reside are uniformly distributed. This homogeneity assumption permits the geometry of samples and calibration standards to be approximated by that of a non attenuating line source on the axis of rotation. Other common SGS assumptions are that the detector is perfectly collimated, that its response is flat over its field of view, and that it can be approximated adequately by a line. All of these assumption have led to a preference for homogeneous calibration standards. Preparation and certification of such calibration standards are usually difficult and expensive. Storage and transportation of SGS standards can be inconvenient or even quite troublesome. The authors have proposed and tested an alternative method of SGS calibration that only requires a point-source standard. The proposed technique relies on the empirical determination of a normalized two-dimensional detector response and the measurement of the count rate from a point-source standard located at the response apex. With these data, the system`s response to a distributed, homogeneous samples can …
Date: August 1, 1994
Creator: Sheppard, G. A. & Piquette, E. C.
System: The UNT Digital Library
Sensor-based control of rocket thrust chamber feature location for automated braze paste dispensing (open access)

Sensor-based control of rocket thrust chamber feature location for automated braze paste dispensing

None
Date: August 1, 1994
Creator: Schmitt, D. J.; Novak, J. L.; Maslakowski, J. E. & Starr, G. P.
System: The UNT Digital Library
Support systems for optics in the experiment stations at the Advanced Photon Source (open access)

Support systems for optics in the experiment stations at the Advanced Photon Source

Support systems have been designed for optics in the experiment stations of the Advanced Photon Source at Argonne National Laboratory. These systems utilize modular precision positioning slides and stages arranged in 3-point kinematic mount fashion for optimum mechanical stability. Through the use of novel configurations, these systems can achieve large linear motions, six degree-of-freedom motion, and large load capacities without sacrificing valuable experimental station space. This paper will discuss the designs and specifications of the positioning systems developed.
Date: August 1, 1994
Creator: Barraza, J.; Shu, D. & Kuzay, T. M.
System: The UNT Digital Library
Public participation in the evaluation of innovative environmental cleanup technology (open access)

Public participation in the evaluation of innovative environmental cleanup technology

Technologies for remediation of contamination are urgently needed to clean up US Department of Energy (DOE) sites across the country. DOE is managing a national program to develop, demonstrate, and deploy new technologies with promise to expedite this cleanup. The Integrated Demonstration for Cleanup of Volatile Organic Compounds at Arid Sites (VOC-Arid ID) is one such effort. Time and resources, however, are too limited to be invested in methods of remediation that will never be deployed because they have not been rigorously evaluated or because they face the withering opposition of stakeholders. Therefore the VOC-Arid ID is assessing technology both in terms of its technical effectiveness and its stakeholder acceptability. Only if a technology performs as required and is acceptable to regulators, users of technology, and the public will the VOC-Arid ID recommend its use. What distinguishes public involvement in the VOC-Arid ID is the direct influence stakeholders have on the design of technology demonstrations by working directly with technology developers. Stakeholders participated in defining the criteria with which innovative environmental cleanup technology is being evaluated. The integrated demonstration is committed to providing stakeholders with the information they`ve indicated they need to reach reasoned judgments about the use of specific …
Date: August 1, 1994
Creator: Peterson, T.; McCabe, G.; Serie, P. & Niesen, K.
System: The UNT Digital Library
Positron annihilation studies of defects in molecular beam epitaxy grown III-V layers (open access)

Positron annihilation studies of defects in molecular beam epitaxy grown III-V layers

A summary of recent positron annihilation experiments on molecular beam epitaxy (MBE) grown III-V layers is Presented. Variable energy positron beam measurements on Al{sub 0.32}Ga{sub 0.68}As undoped and Si doped have been completed. Positron trapping at a open volume defect in Al{sub 0.32}Ga{sub 0.68}:Si for temperatures from 300 to 25 K in the dark was observed. The positron trap was lost after 1.3 eV illumination at 25K. These results indicate an open volume defect is associated with the local structure of the deep donor state of the DX center. Stability of MBE GaAs to thermal annealing war, investigated over the temperature range of 230 to 700{degrees}C, Proximity wafer furnace anneals in flowing argon were used, Samples grown above 450{degrees}C were shown to be stable but for sample below this temperature an anneal induced vacancy related defect was produced for anneals between 400 and 500{degrees}C. The nature of the defect was shown to be different for material grown at 350 and 230{degrees}C. Activation energies of 2.5 eV to 2.3 eV were obtained from isochronal anneal experiments for samples grown at 350 and 230{degrees}C, respectively.
Date: August 1, 1994
Creator: Umlor, M. T.; Keeble, D. J.; Asoka-Kumar, P.; Lynn, K. G. & Cooke, P. W.
System: The UNT Digital Library
Ion Emission Intensity Ratios as a Function of Electrode Gap, Melting Current, and Pressure During Low Current Vacuum Arc Remelting (open access)

Ion Emission Intensity Ratios as a Function of Electrode Gap, Melting Current, and Pressure During Low Current Vacuum Arc Remelting

The arc energy distribution in the electrode gap plays a central role in the vacuum arc remelting (VAR) process. However, very little has been done to investigate the response of this important process variable to changes in process parameters. Emission spectroscopy was used to investigate variations in arc energy in the annulus of a VAR furnace during melting of 0.43 m diameter Alloy 718 electrode into 0.51 in diameter ingot. Time averaged (1 second) intensity data from various chromium atom and ion (Cr{sup +}) emission lines were simultaneously collected and selected intensity ratios were subsequently used as air energy indicators. These studies were carried out as a function of melting current, electrode gap, and CO partial pressure. The data were modeled and the ion electronic energy was found to be a function of electrode gap, the energy content of the ionic vapor decreasing with increasing gap length; the ion ratios were not found to be sensitive to pressure. On the other hand, the chromium atom electronic energy was difficult to model in the factor space investigated, but was determined to be sensitive, to pressure. The difference in character of the chromium ion and atom energy fluctuations in the furnace annulus …
Date: August 1, 1994
Creator: Williamson, R. L. & Grose, S. M.
System: The UNT Digital Library
Remote detection of trace effluents using resonance Raman spectroscopy (open access)

Remote detection of trace effluents using resonance Raman spectroscopy

None
Date: August 1, 1994
Creator: Sedlacek, A. J. & Chen, C. L.
System: The UNT Digital Library
Alarm annunciation in a graphical environment (open access)

Alarm annunciation in a graphical environment

Well-designed graphical user interfaces, such as Microsoft Windows{trademark} or UNIX{trademark} -- based X-Windows, provide a capability for enhanced display of security alarm information. Conversely, a poorly designed interface can quickly overwhelm an operator. This paper describes types of graphical information that can be displayed and offers guidance on how to best display that information. Limits are proposed for the complexity of the user interface, and guidelines are suggested for the display of maps and sensors.
Date: August 1, 1994
Creator: Adams, D. G.
System: The UNT Digital Library