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Accelerator developments since the ZGS by ZGS people (open access)

Accelerator developments since the ZGS by ZGS people

The ZGS was a facility, as well as an organization, where people got together to pursue a common goal of doing exciting science of the day. In this note, the authors describe notable events related to accelerators and accelerator people since the closing of the ZGS program some 15 years ago. Many of the same ZGS people have been carrying out the state-of-the art accelerator work around the Laboratory with the same dedication that characterized their work in the earlier days. First the authors describe how the activities were re-organized after the closing of the ZGS, the migration of people, and the organizational evolution since that time. Doing this shows the similarity between the birth of the ZGS and the birth of the Advanced Photon Source (APS). Then, some of the accelerator work by the former ZGS people are described. These include: (1) Intense Pulsed Neutron Source (IPNS), (2) GeV Electron Microtron (GEM), (3) Wake Field Accelerator Test Facility, (4) Advanced Photon Source, and (5) IPNS Upgrade.
Date: December 31, 1994
Creator: Cho, Y.
System: The UNT Digital Library
Accelerator-driven destruction of long-lived radioactive waste and energy production (open access)

Accelerator-driven destruction of long-lived radioactive waste and energy production

Nuclear waste management involves many issues. ATW is an option that can assist a repository by enhancing its capability and thereby assist nuclear waste management. Technology advances and the recent release of liquid metal coolant information from Russia has had an enormous impact on the viability of an ATW system. It now appears economic with many repository enhancing attributes. In time, an ATW option added to present repository activities will provide the public with a nuclear fuel cycle that is acceptable from economic and environmental points of view.
Date: December 31, 1997
Creator: Schriber, S. O.
System: The UNT Digital Library
An accelerator-driven reactor for meeting future energy demand (open access)

An accelerator-driven reactor for meeting future energy demand

Fissile fuel can be produced at a high rate using an accelerator-driven Pu-fueled subcritical fast reactor which avoids encountering a shortage of Pu during a high growth rate in the production of nuclear energy. Furthermore, the necessity of the early introduction of the fast reactor can be moderated. Subcritical operation provides flexible nuclear energy options along with high neutron economy for producing the fuel, for transmuting high-level waste such as minor actinides, and for efficiently converting excess and military Pu into proliferation-resistant fuel.
Date: December 31, 1997
Creator: Takahashi, Hiroshi; Yang, Y. & Yu, A.
System: The UNT Digital Library
Accelerator modeling system for the future (open access)

Accelerator modeling system for the future

Many computer programs and a variety of models exist for the design of accelerator lattices and the correction of errors. Many physicists contributed to this work by developing codes to suit a variety of machines. At present, we are integrating some of these codes into a unified framework to design and control any type of machine. We will refer to this system of interactive accelerator design, control, and analysis codes as the All-In-One Modeling system (AIM). This paper will explore the utilities of AIM for future accelerator modeling and control. As an example, we will describe a procedure to produce both a linear and a nonlinear model for SPEAR.
Date: December 1, 1994
Creator: Lee, M.; Cai, Y. & Tran, P.
System: The UNT Digital Library
Accelerator Physics and Modeling: Proceedings (open access)

Accelerator Physics and Modeling: Proceedings

This report contains papers on the following topics: Physics of high brightness beams; radio frequency beam conditioner for fast-wave free-electron generators of coherent radiation; wake-field and space-charge effects on high brightness beams. Calculations and measured results for BNL-ATF; non-linear orbit theory and accelerator design; general problems of modeling for accelerators; development and application of dispersive soft ferrite models for time-domain simulation; and bunch lengthening in the SLC damping rings.
Date: December 31, 1991
Creator: Parsa, Zoreh
System: The UNT Digital Library
Accelerator physics and technology limitations to ultimate energy and luminosity in very large hadron colliders (open access)

Accelerator physics and technology limitations to ultimate energy and luminosity in very large hadron colliders

The following presents a study of the accelerator physics and technology limitations to ultimate energy and luminosity in very large hadron colliders (VLHCs). The main accelerator physics limitations to ultimate energy and luminosity in future energy frontier hadron colliders are synchrotron radiation (SR) power, proton-collision debris power in the interaction regions (IR), number of events-per-crossing, stored energy per beam and beam-stability [1]. Quantitative estimates of these limits were made and translated into scaling laws that could be inscribed into the particle energy versus machine size plane to delimit the boundaries for possible VLHCs. Eventually, accelerator simulations were performed to obtain the maximum achievable luminosities within these boundaries. Although this study aimed at investigating a general VLHC, it was unavoidable to refer in some instances to the recently studied, [2], 200 TeV center-of-mass energy VLHC stage-2 design (VLHC-2). A more thorough rendering of this work can be found in [3].
Date: December 5, 2002
Creator: al., P. Bauer et
System: The UNT Digital Library
Accelerator System Design, Injection, Extraction and Beam-Material Interaction: Working Group C Summary Report (open access)

Accelerator System Design, Injection, Extraction and Beam-Material Interaction: Working Group C Summary Report

None
Date: December 1, 2012
Creator: Mokhov, N. V. & Li, D.
System: The UNT Digital Library
Accelerator Transmutation of Waste Blanket Considerations (open access)

Accelerator Transmutation of Waste Blanket Considerations

Accelerator transmutation of waste (ATW) is one approach for reducing the amount of actinides and long-lived fission products that eventually will be sent to a repository. The ATW accelerator generates high-energy protons, which strike a target and produce spallation neutrons. The spallation neutrons transmute waste in a region that surrounds the spallation target. It is desirable for the waste transmutation region (WTR) to have significant neutron multiplication (a factor of 10 or higher) to keep the required accelerator size reasonable. The WTR is subcritical and is thus not required to generate a self-sustaining fission reaction in the waste. The elimination of this requirement allows the ATW system to be optimized for reducing the hazard from nuclear waste without the concerns associated with safely maintaining criticality. Subcritical operation allows waste compositions with positive prompt reactivity feedback coefficients to be considered, allows waste forms optimized for processing to be considered, and allows additional design flexibility. The WTR will be designed so that criticality cannot be achieved during any credible accident scenario. The primary advantage of the ATW approach is thus the design and operational flexibility gained from subcritical operation. The primary disadvantage of the ATW approach is the expense and complexity of …
Date: December 1, 1997
Creator: Houts, Michael G.; Bjornberg, Mikael & Poston, David I.
System: The UNT Digital Library
Accelerators for high energy physics research (open access)

Accelerators for high energy physics research

A brief survey of particle accelerators as research tools for high energy physics is given. The survey includes existing accelerators, as well as those envisioned for the future.
Date: December 1, 1995
Creator: Chao, A.
System: The UNT Digital Library
Acceptance criteria for heat exchanger head staybolts (open access)

Acceptance criteria for heat exchanger head staybolts

Each of the six primary coolant loop systems of the Savannah River Site production reactors contains two parallel single-pass heat exchangers to transfer heat from the primary coolant (D{sub 2}O) to the secondary cooling water (H{sub 2}O). The configuration of the heat exchangers includes a plenary space defined by the heat exchanger tubesheet and the heat exchanger head at both the heat exchanger inlet and outlet to the primary piping. The primary restraint of the heat exchanger head (Type 304 stainless steel) is provided by 84 staybolts (Type 303 stainless steel) which attach to the tubesheet. The staybolts were cap seal-welded in the mid-1960`s and are immersed in moderator. Access to inspect the staybolts is limited to a recently-developed ultrasonic technique shooting a beam through the staybolt assembly. Acceptance Criteria to allow disposition of flaws detected by UT inspection have been developed. The structural adequacy to protect against collapse loading of the head is demonstrated by finite element analysis of the head assembly and fracture analysis of flaw postulates in the staybolts. Both normal operation and normal operation plus seismic loading conditions were considered. Several bounding cases containing various configurations of nonactive (exceeding critical flaw size) staybolts were analyzed. The …
Date: December 31, 1991
Creator: Sindelar, R. L.; Lam, P. S.; Barnes, D. M.; Placr, A. & Morrison, J. M.
System: The UNT Digital Library
Acceptance criteria for interim dry storage of aluminum-clad fuels (open access)

Acceptance criteria for interim dry storage of aluminum-clad fuels

Direct repository disposal of foreign and domestic research reactor fuels owned by the United States Department of Energy is an alternative to reprocessing (together with vitrification of the high level waste and storage in an engineered barrier) for ultimate disposition. Neither the storage systems nor the requirements and specifications for acceptable forms for direct repository disposal have been developed; therefore, an interim storage strategy is needed to safely store these fuels. Dry storage (within identified limits) of the fuels received from wet-basin storage would avoid excessive degradation to assure post-storage handleability, a full range of ultimate disposal options, criticality safety, and provide for maintaining confinement by the fuel/clad system. Dry storage requirements and technologies for US commercial fuels, specifically zircaloy-clad fuels under inert cover gas, are well established. Dry storage requirements and technologies for a system with a design life of 40 years for dry storage of aluminum-clad foreign and domestic research reactor fuels are being developed by various groups within programs sponsored by the DOE.
Date: December 31, 1994
Creator: Sindelar, R. L.; Peacock, H. B. Jr.; Iyer, N. C. & Louthan, M. R. Jr.
System: The UNT Digital Library
Access and Use of Information Resources in Assessing Health Risks From Chemical Exposure: Proceedings (open access)

Access and Use of Information Resources in Assessing Health Risks From Chemical Exposure: Proceedings

Health risk assessment is based on access to comprehensive information about potentially hazardous agents in question. Relevant information is scattered throughout the literature, and often is not readily accessible. To be useful in assessment efforts, emerging scientific findings, risk assess parameters, and associated data must be compiled and evaluated systemically. The US Environmental Protection Agency (EPA) and Oak Ridge National Laboratory (ORNL) are among the federal agencies heavily involved in this effort. This symposium was a direct response by EPA and ORNL to the expressed needs of individuals involved in assessing risks from chemical exposure. In an effort to examine the state of the risk assessment process, the availability of toxicological information, and the future development and transfer of this information, the symposium provided an excellent cadre of speakers and participants from state and federal agencies, academia and research laboratories to address these topics. This stimulating and productive gathering discussed concerns associated with (1) environmental contamination by chemicals; (2) laws regulating chemicals; (3) information needs and resources; (4) applications; (5) challenges and priorities; and (6)future issues. Individual reports are processed separately for the data bases.
Date: December 31, 1990
Creator: unknown
System: The UNT Digital Library
Accident information needs (open access)

Accident information needs

A Five-step methodology has been developed to evaluate information needs for nuclear power plants under accident conditions and the availability of plant instrumentation during severe accidents. Step 1 examines the credible accidents and their relationships to plant safety functions. Step 2 determines the information personnel involved in accident management will need to understand plant behavior. Step 3 determines the capability of the instrumentation to function properly under severe accident conditions. Step 4 determines the conditions expected during the identified severe accidents. Step 5 compares the instrument capabilities and the severe accident conditions to evaluate the availability of the instrumentation to supply needed plant information.
Date: December 31, 1992
Creator: Hanson, D. J.; Arcieri, W. C. & Ward, L. W.
System: The UNT Digital Library
Accident sequence precursor events with age-related contributors (open access)

Accident sequence precursor events with age-related contributors

The Accident Sequence Precursor (ASP) Program at ORNL analyzed about 14.000 Licensee Event Reports (LERs) filed by US nuclear power plants 1987--1993. There were 193 events identified as precursors to potential severe core accident sequences. These are reported in G/CR-4674. Volumes 7 through 20. Under the NRC Nuclear Plant Aging Research program, the authors evaluated these events to determine the extent to which component aging played a role. Events were selected that involved age-related equipment degradation that initiated an event or contributed to an event sequence. For the 7-year period, ORNL identified 36 events that involved aging degradation as a contributor to an ASP event. Except for 1992, the percentage of age-related events within the total number of ASP events over the 7-year period ({approximately}19%) appears fairly consistent up to 1991. No correlation between plant ape and number of precursor events was found. A summary list of the age-related events is presented in the report.
Date: December 31, 1995
Creator: Murphy, G.A. & Kohn, W.E.
System: The UNT Digital Library
Accident simulation in a chemical process facility at the Savannah River Site. Revision 1 (open access)

Accident simulation in a chemical process facility at the Savannah River Site. Revision 1

The US Department of Energy requires Westinghouse Savannah River Company to safely operate the chemical separations facilities at the Savannah River Site (SRS). As part of the safety analysis program, simulation of a proposed frame waste recovery (FWR) system is needed to determine the possible accident consequences that may affect public safety. This paper details the simulation process for the proposed frame waste recovery process and describes the analytical tools used in order to make estimates of accident consequences. Since the process in question has been operated, historical data and statistics about its operation are available. Software tools have been developed to allow analysis of the frame waste recovery system, including the generation of system specific dose conversion factors for a number of unique situations. Accident scenarios involving spilled liquid material are analyzed and account for the specific floor geometry of the facility. Confinement and filtration systems are considered. Analysis of source terms is a limiting factor which affects the entire evaluation process. In the past, facility source terms were generally constant with occasional variations from established patterns. As new site missions unfold, significant variations in source terms can be expected. The impact of these variations on the safety analysis …
Date: December 31, 1993
Creator: Hope, E. P.
System: The UNT Digital Library
The accident site portable integrated video system (open access)

The accident site portable integrated video system

This paper presents a high bandwidth fiber-optic communication system intended for post accident recovery of weapons. The system provides bi-directional multichannel, and multi-media communications. Two smaller systems that were developed as direct spin-offs of the larger system are also briefly discussed.
Date: December 31, 1995
Creator: Jones, D. P.; Shirey, D. L. & Amai, W. A.
System: The UNT Digital Library
Accomplishments of the American-Polish Program for Elimination of Low Emissions in Krakow (open access)

Accomplishments of the American-Polish Program for Elimination of Low Emissions in Krakow

Since 1990 the US Department of Energy (DOE) has been involved in a program aimed at reducing air pollution caused by small, coal-fired sources in Poland. The activity is focused on the city of Cracow, Poland with the intention that results will be applicable and extendable to the entire region. The effort under this program has been focused into 5 main areas of interest as follows: (1) energy conservation and extension of central station district heating; (2) replacement of coal- and coke-fired boilers with natural gas-fired boilers; (3) replacement of coal-fired home stoves with electric heating appliances; (4) reduction of emissions from stoker-fired boiler houses; and (5) reduction of emissions from coal-fired home heating stoves.
Date: December 31, 1998
Creator: Butcher, T. A. & Pierce, B.
System: The UNT Digital Library
Accrediting industrial safety training programs (open access)

Accrediting industrial safety training programs

There are job-specific training requirements established by regulations that Impose stringent training requirements on a contractor, for example, the Occupational Safety & Health Act (OSHA). Failure to comply with OSHA training requirements can result in severe penalties being levied against a company. Although an accredited training program is expensive, it is a possible solution for minimizing risks associated with job-specific training requirements for employees. Operating DOE contractors direct approximately 10 percent of the operating funds toward training activities. Training needs for contractors span a broad range, from requirements awareness training for managers, to general training required on a one-time basis for all employees, to highly specialized training programs for employees involved In clean-up operations at hazardous waste sites. With this kind of an investment in training, it is logical to maximize the most return on an investment of training funds and to limit exposure to liability suits whenever possible. This presentation will provide an overview of accredited industrial safety programs. The criteria for accredited industrial safety programs will be defined. The question of whether accredited training programs are necessary will be examined. Finally, advantages and disadvantages will be identified for accrediting industrial safety training programs.
Date: December 31, 1992
Creator: Beitel, L.
System: The UNT Digital Library
Accumulated surface damage on ZnS crystals produced by closely spaced pairs of picosecond laser pulses (open access)

Accumulated surface damage on ZnS crystals produced by closely spaced pairs of picosecond laser pulses

Excitation of a transparent ZnS crystal by repetitive picosecond dye laser pulses causes an accumulated surface modification leading to optical damage. The onset of the damage is detected by an abrupt increase in the emission of neutral Zn (and possibly S/sub 2/) from the surface. Comparison of the neutral emission thresholds with pulse-pair and single-pulse excitation shows that linear absorption is the dominant laser-surface interaction. In general, this measurement technique shows considerable promise for investigating the possible influence of nonlinear absorption or excitation processes on damage mechanisms. The data suggest that heating of small absorbing regions produces the surface modification that leads to the observed surface ablation. The nature of the damage observed at fluences above the threshold suggests that it is caused by heating of a relatively large (/approximately/10 - 100 ..mu..m) surface region that has been modified by the accumulation pulses. 3 refs., 5 figs.
Date: December 1, 1988
Creator: Chase, L. L. & Lee, H. W. H.
System: The UNT Digital Library
Accumulation and altered localization of telomere-associated protein TRF2 in immortally transformed and tumor-derived human breast cells (open access)

Accumulation and altered localization of telomere-associated protein TRF2 in immortally transformed and tumor-derived human breast cells

We have used cultured human mammary epithelial cells (HMEC) and breast tumor-derived lines to gain information on defects that occur during breast cancer progression. HMEC immortalized by a variety of agents (the chemical carcinogen benzo(a)pyrene, oncogenes c-myc and ZNF217, and/or dominant negative p53 genetic suppressor element GSE22) displayed marked up regulation (10-15 fold) of the telomere binding protein, TRF2. Up-regulation of TRF2 protein was apparently due to differences in post-transcriptional regulation, as mRNA levels remained comparable in finite life span and immortal HMEC. TRF2 protein was not up-regulated by the oncogenic agents alone in the absence of immortalization, nor by expression of exogenously introduced hTERT genes. We found TRF2 levels to be at least 2-fold higher than in control cells in 11/15 breast tumor cell lines, suggesting that elevated TRF2 levels are a frequent occurrence during the transformation of breast tumor cells in vivo. The dispersed distribution of TRF2 throughout the nuclei in some immortalized and tumor-derived cells indicated that not all the TRF2 was associated with telomeres in these cells. The process responsible for accumulation of TRF2 in immortalized HMEC and breast tumor-derived cell lines may promote tumorigenesis by contributing to the cells ability to maintain an indefinite life …
Date: December 23, 2004
Creator: Nijjar, Tarlochan; Bassett, Ekaterina; Garbe, James; Takenaka, Yasuhiro; Stampfer, Martha R.; Gilley, David et al.
System: The UNT Digital Library
Accuracy and precision of compartmental model parameters obtained from directly estimated dynamic SPECT time-activity curves (open access)

Accuracy and precision of compartmental model parameters obtained from directly estimated dynamic SPECT time-activity curves

None
Date: December 2, 2002
Creator: Reutter, Bryan W.; Gullberg, Grant T. & Huesman, Ronald H.
System: The UNT Digital Library
Accuracy of Analog Fiber-Optic Links in Pulsed Radiation Environments (open access)

Accuracy of Analog Fiber-Optic Links in Pulsed Radiation Environments

Interferometric fiber-optic links used in pulsed-power experiments are evaluated for accuracy in the presence of radiation fields which alter fiber transmission. Amplitude-modulated format (e.g., Mach-Zehnder) and phase-modulated formats are compared. Historically, studies of radiation effects on optical fibers have focused on degradation and recovery of the fibers transmission properties; such work is either in the context of survivability of fibers in catastrophic conditions or suitability of fibers installed for command and control systems within an experimental facility [1], [2]. In this work, we consider links used to transmit realtime diagnostic data, and we analyze the error introduced by radiation effects during the drive pulse. The result is increased uncertainties in key parameters required to unfold the sinusoidal transfer function. Two types of modulation are considered: amplitude modulation typical of a Mach-Zehnder (M-Z) modulator [3], and phase modulation, which offers more flexible demodulation options but relies on the spatiotemporal coherence of the light in the fiber. The M-Z link is shown schematically in Fig. 1, and the phase-modulated link is shown in Fig. 2. We present data from two experimental environments: one with intense, controlled radiation fields to simulate conditions expected at the next generation of pulsed-power facilities, and the second …
Date: December 1, 2007
Creator: E. K. Miller, G. S. Macrum, I. J. McKenna, et al.
System: The UNT Digital Library
Accurate and portable weigh-in-motion system for manifesting air cargo (open access)

Accurate and portable weigh-in-motion system for manifesting air cargo

An automated and portable weigh-in-motion system has been developed at Oak Ridge National Laboratory for the purpose of manifesting cargo onto aircraft. The system has an accuracv range of {plus_minus} 3.0% to {plus_minus} 6.0% measuring gross vehicle weight and locating the center of balance of moving vehicles at speeds of 1 to 5 mph. This paper reviews the control/user interface system and weight determination algorithm developed to acquire, process, and interpret multiple sensor inputs. The development effort resulted in a self-zeroing, user-friendly system capable of weighing a wide range of vehicles in any random order. The control system is based on the STANDARD (STD) bus and incorporates custom-designed data acquisition and sensor fusion hardware controlled by a personal computer (PC) based single-board computer. The user interface is written in the ``C`` language to display number of axles, axle weight, axle spacing, gross weight, and center of balance. The weighing algorithm developed will function with any linear weight sensor and a set of four axle switches per sensor.
Date: December 1, 1995
Creator: Nodine, R. N.; Scudiere, M. B. & Jordan, J. K.
System: The UNT Digital Library
[ACEEE summer study on energy efficiency in buildings]. Final technical report (open access)

[ACEEE summer study on energy efficiency in buildings]. Final technical report

The ACEEE Summer Study is a biennial conference that aims to bring together the foremost researchers, practitioners and policy makers involved in research on energy efficiency in buildings. The 1990 Summer Study had the objective to facilitate the exchange of research and implementation results and encourage the advancement of knowledge in the field of energy efficiency in buildings. The research papers presented at the conference published and distributed. Two hundred seventy two papers were presented. These individual papers, published in ten volumes, have been processed separately for the Energy Data Base.
Date: December 31, 1990
Creator: unknown
System: The UNT Digital Library