By Topic

Nuclear Science Symposium and Medical Imaging Conference, 1991., Conference Record of the 1991 IEEE

Date 2-9 Nov. 1991

Filter Results

Displaying Results 1 - 25 of 467
  • The integrated maintenance program

    Publication Year: 1991 , Page(s): 1410 - 1413 vol.2
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (289 KB)  

    The authors point out that a comprehensive and integrated approach is required to address adequately the varied needs and interfaces which drive a plant maintenance program. The functional performance designed into the equipment must be understood and combined with all the requirements external to the equipment in order to provide an effective and justifiable maintenance program. A systematic process of development and documentation of the engineering basis for the overall maintenance plan can satisfy all the necessary requirements while providing a very efficient means to build and maintain the necessary documentation. Finally, particular attention to the details of program interfaces is essential.<> View full abstract»

    Full text access may be available. Click article title to sign in or learn about subscription options.
  • Advanced control rooms and crew performance issues: implications for human reliability

    Publication Year: 1991 , Page(s): 1405 - 1409 vol.2
    Cited by:  Papers (1)
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (487 KB)  

    Recent trends in advanced control room (ACR) design are considered with respect to their impact on human performance. It is concluded that the effects of advanced technology on human performance cannot be assumed to be positive. Conducting human reliability analyses for advanced plants is made difficult by limitations in the general knowledge about the role of human operators in ACRs, the effects of specific design characteristics on human performance, the lack of available databases, and the lack of available subject matter expertise. Thus, there is a heightened need to precisely and thoroughly document the process of human action identification, evaluation, and quantification. In the longer term, research is needed on the effects of advanced technology on human performance, including the assessment of industry experience on a world-wide basis. The development of models to better understand the cognitive underpinnings of human errors appears to be an especially promising path.<> View full abstract»

    Full text access may be available. Click article title to sign in or learn about subscription options.
  • Optimized neutron monitoring system for the SBWR

    Publication Year: 1991 , Page(s): 1400 - 1404 vol.2
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (441 KB)  

    The Simplified Boiling Water Reactor (SBWR) is a 600-MWe nuclear power plant developed by an international design team led by GE. The SBWR incorporates features which simplify the plant design and make it easier to operate and maintain. The neutron monitoring system (NMS) of the SBWR contains the startup range neutron monitors, the power range neutron monitors, and the core power calibration instrument. In the current SBWR design configuration, many simplified features have been incorporated into the NMS design. The number of local power monitors in the NMS is reduced as the result of enhanced detector and electronic designs and improvements in core power calculation methodology. The core power calibration instruments are also improved such that the out-of-vessel mechanical components associated with the conventional calibration instrument are eliminated. With the incorporation of these features into the SBWR neutron monitoring system design, plant operation and maintenance activities can be significantly simplified.<> View full abstract»

    Full text access may be available. Click article title to sign in or learn about subscription options.
  • Advanced reactor instrumentation and control reliability and risk assessment

    Publication Year: 1991 , Page(s): 1394 - 1399 vol.2
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (416 KB)  

    Advanced nuclear power reactors will use different approaches to achieving a higher level of safety than the first generation. One approach uses the technological developments in computation and electronics in the form of digital instrumentation and control (I&C) to enhance the reliability and accuracy of information for plant control, responding to the information, and controlling the plant and its systems under normal and upset environments in various states of degradation. Evaluating the reliability and safety of advanced I&C systems requires determining the reliability of the I&C used in the advanced reactors, which involves distributed processing, data pile-up, interactive systems, the man-machine interface, various forms of automatic control, and systems interactions. From these analyses will come an understanding of the potential of the new I&C, and protection from its vulnerabilities to enhance the safe operation of the new plants. Technological, safety, reliability, and regulatory issues associated with advanced I&C for the new reactors are discussed, and suggested approaches to their resolution are presented.<> View full abstract»

    Full text access may be available. Click article title to sign in or learn about subscription options.
  • Advanced alarm management in the AWARE system

    Publication Year: 1991 , Page(s): 1389 - 1393 vol.2
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (363 KB)  

    Westinghouse is currently constructing and installing the AWARE alarm system for a Swiss utility. This system, which utilizes a novel conceptual approach to achieve the level of effectiveness required for a nuclear power plant, alarm management system, will be an integral part of an extensive control room upgrade to the utility. AWARE is designed to eliminate the alarm 'avalanche' problem associated with major off-normal events, but will maintain the sensitivity necessary to support minor disturbances. This is accomplished by the use of expert-specified alarm logic, alarm prioritization according to the plant's functional organization, and computer presentation of the alarm messages. The AWARE system employs a redundant, UNIX-workstation-based, distributed computer architecture to achieve high reliability and state-of-the-art performance. The alarm logic algorithms, prioritization rules, and alarm messages are represented as data within the system and are easily maintained by the plant's operating staff.<> View full abstract»

    Full text access may be available. Click article title to sign in or learn about subscription options.
  • Reliability assurance for regulation of advanced reactors

    Publication Year: 1991 , Page(s): 1383 - 1388 vol.2
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (456 KB)  

    Advanced nuclear power plants must achieve higher levels of safety than the first generation of plants. Showing that this is indeed true provides new challenges to reliability and risk assessment methods in the analysis of the designs employing passive and semipassive protection. Reliability assurance of the advanced reactor system is important for determining the safety of the design and for determining the plant operability. Safety is the primary concern, but operability is considered indicative of good and safe operation. The authors discuss several concerns for reliability assurance of the advanced design, encompassing reliability determination, level of detail required in advanced reactor submittals, data for reliability assurance, systems interactions and common cause effects, passive component reliability, PRA-based configuration control system, and inspection, training, maintenance, and test requirements. Suggested approaches are provided for addressing each of these topics.<> View full abstract»

    Full text access may be available. Click article title to sign in or learn about subscription options.
  • Advanced boiling water reactor, the next generation-status and future

    Publication Year: 1991 , Page(s): 1377 - 1382 vol.2
    Cited by:  Patents (1)
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (515 KB)  

    The advanced boiling water reactor (ABWR) is an advanced water reactor designed by an international team of engineers and designers to address the utility and public needs for the next generation of power plants. The major emphasis in the design of the plant has been on improved operability and maintainability. This has led to an overall plant design that is simpler to build, maintain, and operate and at the same time has significantly enhanced safety features, including several features that are inherent to BWR designs and ensure 'passive' responses to transients and accidents. The author also discusses other key features of the ABWR: internal recirculation pumps, fine motion control rod drives, digital control and instrumentation, multiplexed fiber optic cabling network, pressure suppression containment, structural integration of the containment and reactor building, and advanced turbine/generator with 52-in last stage buckets. The 1356 MWe ABWR design is being applied as a two unit project by the Tokyo Electric Power Co. Inc., at its Kashiwazaki-Kariwa site in Japan. Construction began September 1991 and commercial operation is scheduled for 1996, with the second unit one year later.<> View full abstract»

    Full text access may be available. Click article title to sign in or learn about subscription options.
  • New US nuclear plants: one scenario

    Publication Year: 1991 , Page(s): 1373 - 1376 vol.2
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (308 KB)  

    It is pointed out that the obstacles to new nuclear power plants in the US are many and well-known, but that there are some signs pointing toward at least a partial removal of the obstacles. Electric load continues to grow above forecast rates in many regions. New designs are being developed for smaller, simpler plants with improved safety features, shorter construction schedules, and lower capital requirements, resulting in less financial exposure to the owner. Also, legislative and regulatory initiatives are underway to reduce the uncertainty in the licensing environment. The author reviews these hopeful indications and postulates one plausible scenario for the near-term revival of domestic nuclear plant construction in the US for base load electric generation. According to this scenario, during an energy supply crisis, a group of electric utilities, with favorable nuclear experience, form a consortium with other industry participants, such as suppliers, architect engineers, and constructors, to develop and implement a project which would include several standardized ALWR (advanced light water reactor) units, with each utility owning a portion of each unit.<> View full abstract»

    Full text access may be available. Click article title to sign in or learn about subscription options.
  • Intelligent system controller for remote systems

    Publication Year: 1991 , Page(s): 1369 - 1370 vol.2
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (93 KB)  

    Summary form only given. The US Department of Energy's Office of Technology Development (OTD) has sponsored the development of the Generic Intelligent System Controller (GISC) for application to remote system control. Of primary interest to the OTD is the development of technologies which result in faster, safer, and cheaper clean up of hazardous waste sites. The GISC development project supports these goals by seeking to develop a modular robotic control system which reduces the time and cost of development by allowing reuse of control system software and uses computer models to improve the safety of remote site clean-up. GISC is termed an intelligent control system because computer models reduce development time by automating much of the system programming, and they monitor all operations for safety. Intelligent decision making algorithms evaluate the known environment represented by a world model, plan collision-free robot motions, and then automatically generate the robot command sequences necessary to execute the desired robot motions. Visualization software technologies provides the operator of the robot system with animated graphic displays of the computer's knowledge base.<> View full abstract»

    Full text access may be available. Click article title to sign in or learn about subscription options.
  • Vacuum mechatronic laser alignment system on the NOVA laser

    Publication Year: 1991
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (27 KB)  

    The experiments conducted on NOVA are done to investigate inertially confined laser fusion reactions. To this end, the ten beams of the laser are aligned to within 30 mu m. The target chamber employs a vacuum mechatronic based reticle/target positioning system to accomplish this. It is a five degree-of-freedom chamber resident system, known as the Alignment Aids Positioner (AAP). The AAP aids in beam and diagnostic alignment by accurately positioning a reticle at the target chamber center within 7 mu m. The AAP system increases target positioning and alignment flexibility and accuracy through the use of a computer-controlled multi-degree-of-freedom stage assembly. The AAP has two positioning regimes to move the alignment reticle and do beam alignment. One is coarse positioning in the Y-Z plane that moves a high-resolution stage assembly to target chamber center. The other regime is high-resolution movement in the X, Y, Z and theta directions.<> View full abstract»

    Full text access may be available. Click article title to sign in or learn about subscription options.
  • Development of an automated glovebox system for nuclear material pyrochemical processing

    Publication Year: 1991
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (21 KB)  

    Summary form only given. Lawrence Livermore National Laboratory is developing an automated nuclear material pyrochemical processing system that synthesizes technology advances in robotics, remote and automated control, material and component hardening, and crucible furnaces. The system will increase productivity and yield, and reduce risks and routine exposures for operators. Design constraints have included the hostile environments, nuclear material and robot safety criteria, adaptation of commercial robotics, and extreme seismic spectra, and need to show significant improvements over current practice. The results to data are a working tilt-pour furnace in a developmental glovebox presently incorporating a modified commercial gantry robot.<> View full abstract»

    Full text access may be available. Click article title to sign in or learn about subscription options.
  • DOE SNM processing glovebox material exposure environments

    Publication Year: 1991
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (19 KB)  

    Summary form only given. Robotics, teleoperation, and other automated equipment is being developed for nuclear material processing gloveboxes to increase productivity and reduce risks and routine operator exposures. Development time and costs directly relate to the extent that subsystems must be specially chosen or modified for specific glovebox environments. LLNL (Lawrence Livermore National Laboratory) has surveyed the types of glovebox environments within the US DOE (Department of Energy) complex to characterize the nature of possible applications. Resulting matrices permit comparison of hostile environment levels to a glovebox usage and of hardening measures with benefits.<> View full abstract»

    Full text access may be available. Click article title to sign in or learn about subscription options.
  • Low-cost teleoperator-controlled vehicle for damage assessment and radiation dose measurement

    Publication Year: 1991 , Page(s): 1361 - 1365 vol.2
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (343 KB)  

    A low-cost, disposable, radio-controlled, remote-reading, ionizing radiation and surveillance teleoperator reentry vehicle has been built. The vehicle carries equipment, measures radiation level, and evaluates building conditions. The basic vehicle, radio control with amplifiers, telemetry, elevator, and video camera with monitor cost less than $2500. Velcro-mounted alpha, beta-gamma, and neutron sensing equipment is used in the system. Many types of health physics radiation measuring equipment may be substituted on the vehicle. Power of the vehicle equipment is carried on board and supplied by sealed lead-acid batteries. Radios are powered by 9-V alkaline batteries. Battery supplies for locomotion, camera, and lights are separate to ensure well-defined vehicle battery capacity while the camera and lights are in use.<> View full abstract»

    Full text access may be available. Click article title to sign in or learn about subscription options.
  • A nuclear survey instrument with imaging capability

    Publication Year: 1991 , Page(s): 1354 - 1357 vol.2
    Cited by:  Patents (3)
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (323 KB)  

    A novel nuclear survey instrument with an imaging capability is being developed for remotely locating high-level radioactive sources with minimal operator exposure. It combines an image of the distribution of radioactivity with a video image of the area containing the source, allowing rapid, remote location of the source. The nuclear imaging system is based on a position-sensitive photomultiplier tube and a diverging hole collimator. The design and measured performance of a prototype device are discussed.<> View full abstract»

    Full text access may be available. Click article title to sign in or learn about subscription options.
  • Radiation effects in materials for an accelerator-based nuclear waste burner

    Publication Year: 1991
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (21 KB)  

    Summary form only given. Nuclear waste isotopes can be transmuted to less-hazardous by forms bombardment with thermal neutrons, which in turn can be produced by stopping of high-energy protons in an appropriate target. Various vessels are required to contain the target material (a liquid or solid high-atomic weight metal or alloy), a moderator (D/sub 2/O), and the nuclear waste slurry. Vessel materials nearest the target will be subjected to a high flux of both fast spallation neutrons and thermal neutrons, while at the outer vessel the radiation environment is characterized by a lower flux of predominantly thermal neutrons. Key materials issues include the nature of displacement damage events from the high-energy neutrons, and the effect of impurities (particularly helium and hydrogen) formed during spallation and thermal neutron capture.<> View full abstract»

    Full text access may be available. Click article title to sign in or learn about subscription options.
  • Integrated five station non-destructive assay system used to support plutonium facility decommissioning

    Publication Year: 1991
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (28 KB)  

    Summary form only given. Decontamination and decommissioning activities at the NFS, Erwin mixed oxide fuel fabrication facility began in June 1990. This operation is supported comprehensively with a state-of-the-art, five station non-destructive assay system. A passive neutron counter network provides a real time, on-line criticality safety monitoring at potential holdup points, with a sensitivity level of a few grams Pu. The same system provides quantitative, on-line holdup evaluation. In cell decontamination effectiveness is measured in a large (5-ft*6-ft*10-ft) pulsed neutron differential dieaway unit, operating at a sensitivity level below 10 nCi/gm (200-s assay). Compacted waste bales are quantitatively assayed in a drum size differential dieaway unit with a 1-nCi/gm sensitivity. A combined high-resolution gamma spectrometer/passive neutron coincidence counter is used to quantify Pu scrap and high-yield residues.<> View full abstract»

    Full text access may be available. Click article title to sign in or learn about subscription options.
  • Automated phantom assay system

    Publication Year: 1991 , Page(s): 1349 - 1351 vol.2
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (215 KB)  

    The authors describe an automated phantom assay system developed for assaying phantoms spiked with minute quantities of radionuclides. The system includes a computer-controlled linear-translation table that positions the phantom at exact distances from a spectrometer. A multichannel analyzer (MCA) interfaces with a computer to collect gamma spectral data. Signals transmitted between the controller and the MCA synchronize data collection and phantom positioning. Measured data are then stored on disk for subsequent analysis. The automated system allows continuous unattended operation and ensures reproducible results. It will be used assay long phantoms in the Pacific Northwest Laboratory Phantom Library.<> View full abstract»

    Full text access may be available. Click article title to sign in or learn about subscription options.
  • Calculated thickness of tungsten alloy required for specified attenuation of gamma radiation from /sup 137/Cs

    Publication Year: 1991 , Page(s): 1345 - 1348 vol.2
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (369 KB)  

    The traditional method of evaluating and calibrating health physics instruments is to use a calibrator that consists of a single high-activity gamma radiation level desired for testing. To have accurate radiation intensities inside the calibrator cavity, the attenuator must be designed from precise absorption calculations. The authors report calculations made to determine the thickness of tungsten alloy metal required for specific attenuation. These calculations include the buildup contribution by secondary scattering radiation, and they are compared to values calculated with the buildup factor omitted.<> View full abstract»

    Full text access may be available. Click article title to sign in or learn about subscription options.
  • Ten channel low background alpha radiometer for nondestructive analysis of low activity samples

    Publication Year: 1991 , Page(s): 1343 - 1344 vol.2
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (124 KB)  

    A description of a 10-channel alpha-radiometer with large-area semiconductor detectors is presented. The radiometer is designed for the determination of soil pollution by alpha-active radionuclides using the method of thick samples. The radiometer also provides isotope analysis. The concentration of Pu and Am isotopes in soil samples has been determined.<> View full abstract»

    Full text access may be available. Click article title to sign in or learn about subscription options.
  • A home-made low-cost intelligent counter

    Publication Year: 1991 , Page(s): 1339 - 1342 vol.2
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (250 KB)  

    A versatile low-cost intelligent counter based on the Z80 CPU, 32K RAM, and 74HCT 590 counters has been constructed with five dependent counter channels and a count capacity of up to 65536 for nuclear radiation measurement. The counter can be operated either stand alone from a built-in keyboard for automatic recycling counting or on line with a computer for remote control. The intelligent counter was successfully used in building radon monitoring where the full scope of functions and the convenience of the intelligent counter have been adequately demonstrated.<> View full abstract»

    Full text access may be available. Click article title to sign in or learn about subscription options.
  • A compact neutron detector for the geology application

    Publication Year: 1991 , Page(s): 1334 - 1338 vol.2
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (417 KB)  

    A compact neutron detector has been designed and built for a geology experiment. The detector had to fit inside a 1.5-in-diameter borehole in a large block of concrete. A gas-filled, 1-in-diameter /sup 3/He tube was attached to a 1-in-diameter electronics preamplifier package. The electronics package consists of a cylindrically shaped, high-voltage section and a single-channel analyzer with a buffered output. The low-voltage components are mounted on a printed-circuit board. The circuit board and the high-voltage section are attached to a semicylindrical base. The outputs consist of a light-emitting diode for visual observations and a fixed-width, TTL (transistor transistor logic)-compatible pulse for a counter. This internal assembly is equipped with coaxial connectors and slips into a thin-walled tube that serves as the preamplifier housing. Power for the detector is supplied by an external, high-voltage supply and a 5-VDC supply.<> View full abstract»

    Full text access may be available. Click article title to sign in or learn about subscription options.
  • Tritium monitoring system for near ambient measurements

    Publication Year: 1991 , Page(s): 1330 - 1333 vol.2
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (228 KB)  

    The authors describe the current status of research on an improved tritium measurement system at the Oak Ridge National Laboratory (ORNL) for the US Navy. Present tritium-in-air monitoring systems installed by the Navy can reliably measure to less than 10 mu Ci/m/sup 3/, but medical and safety issues are pushing measurement needs to below 1 mu Ci/m/sup 3/, which is equivalent to 1-10 nCi/ml in liquid samples, using a calcium metal converter. A significant effort has been expended over the past 10 years by the Navy RADIAC Development Program at ORNL on various schemes to improve the detection of tritium in both air and liquid at near ambient levels. One such scheme includes a liquid flow-through system based on an NE102 sponge scintillator with dual photomultiplier tubes for tube noise rejection.<> View full abstract»

    Full text access may be available. Click article title to sign in or learn about subscription options.
  • Long-range alpha detector (LRAD) for contamination monitoring

    Publication Year: 1991 , Page(s): 1324 - 1329 vol.2
    Cited by:  Papers (1)
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (526 KB)  

    The authors describe a novel long-range alpha detector (LRAD) in which alpha particles interact with the ambient air, producing ionization in the air at the rate of about 30000 ion pairs per megaelectronvolt of alpha energy. These charges can be transported over significant distances (several meters) in a moving current of air generated by a small fan. An ion chamber located in front of the fan measures the current carried by the moving ions. The LRAD-based monitor is more sensitive and more thorough than conventional monitors. The authors present current LRAD sensitivity limits and results, practical monitor designs, and proposed uses for LRAD monitors.<> View full abstract»

    Full text access may be available. Click article title to sign in or learn about subscription options.
  • Diffusion screen removal of radon progeny from continuous air monitoring samples

    Publication Year: 1991 , Page(s): 1318 - 1323 vol.2
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (371 KB)  

    Radon progeny are ubiquitous in plutonium facility workplace atmospheres, which often must be continuously monitored for the presence of low concentrations of transuranic contaminants. The alpha decay energy of the /sup 218/Po and /sup 212/Bi (6 MeV) radon and thoron daughters is sufficiently close to the alpha energies of important actinides such as /sup 239/Pu (5.15 MeV) and /sup 241/Am (5.5 MeV) that considerable interference in the process of detection can result. A novel approach to suppressing the contributions of these background alpha-emitters to the transuranic count based on selective removal of high diffusion mobility size particles containing radon daughters has been developed. Laboratory investigations of several factors of determining the performance of such an approach have been completed, and a prototype continuous air monitor has been successfully built and tested incorporating a screened inlet.<> View full abstract»

    Full text access may be available. Click article title to sign in or learn about subscription options.
  • Application of a CdTe gamma-ray spectrometer to remote characterization of high-level radioactive waste tanks

    Publication Year: 1991 , Page(s): 1313 - 1317 vol.2
    Cited by:  Papers (6)
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (247 KB)  

    Small, shielded cadmium telluride (CdTe) semiconductor gamma-ray detectors have been used for in situ radiological characterization of underground high-level radioactive waste tanks. Remote measurements up to 700 R/h have been made in gamma radiation fields. Spectral data have been used to generate qualitative and quantitative radionuclide profiles of high-level radioactive waste tanks. Two electronic spectral enhancement techniques (pulse risetime discrimination and pulse risetime compensation) have been used in order to measure trace isotopes in the presence of large amounts of /sup 137/Cs Spectral resolution better than 1.5% FWHM (full width at half maximum) for the /sup 137/Cs 662-keV photopeak has been obtained.<> View full abstract»

    Full text access may be available. Click article title to sign in or learn about subscription options.