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Acceleration of polarized proton beams (open access)

Acceleration of polarized proton beams

The acceleration of polarized beams in circular accelerators is complicated by the numerous depolarizing spin resonances. Using a partial Siberian snake and a rf dipole that ensure stable adiabatic spin motion during acceleration has made it possible to accelerate polarized protons to 25 GeV at the Brookhaven AGS. Full Siberian snakes are being developed for RHIC to make the acceleration of polarized protons to 250 GeV possible. A similar scheme is being studied for the 800 GeV HERA proton accelerator.
Date: December 31, 1998
Creator: Roser, T.
Object Type: Article
System: The UNT Digital Library
Accelerator production of tritium 700 MHz and 350 MHz klystron test results (open access)

Accelerator production of tritium 700 MHz and 350 MHz klystron test results

The Accelerator Production of Tritium project (APT) utilizes a 1,700 MeV, 100 mA proton Linac. The radio frequency (RF) power is provided by 244 continuous wave (CW) klystron amplifiers at 350 MHz and 700 MHz. All but three of the klystrons operate at a frequency of 700 MHz. The 350 MHz klystrons have a nominal output power of 1.2 MW at a DC-to-RF conversion efficiency of 65%. They are modulating-anode klystrons and operate at a beam voltage and current of 95 kV and 20 A. The design is based on the CERN klystron. The 700 MHz klystron is a new development for APT. Three 700 MHz klystrons are currently under development. Two vendors are each developing a baseline klystron that has a nominal output power of 1.0 MW at a DC-to-RF conversion efficiency of 65%. A 700 MHz klystron is also under development that promises to provide an efficiency in excess of 70%. The 700 MHz klystrons operate at a maximum beam voltage of 95 kV and a maximum beam current of 17 A. The test results of these klystrons will be presented and the design features will be discussed.
Date: December 31, 1998
Creator: Rees, D.; Lynch, M. & Tallerico, P.
Object Type: Report
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.
Object Type: Article
System: The UNT Digital Library
Accretion onto black holes: The power generating mechanism (open access)

Accretion onto black holes: The power generating mechanism

This is the final report of a three-year, Laboratory Directed Research and Development (LDRD) project at Los Alamos National Laboratory (LANL). The physical relationships among accretion disks, quasars, black holes, collimated radio sources and galactic dynamos previously has been only weakly related without explicit cause and effect. We have constructed a physical evolution from large, primordial density perturbations to {open_quotes}damped Lyman alpha clouds,{close_quotes} to galaxy formation, to black holes, jets, and the the galactic dynamo. We have derived the general relativistic distortions of radiation emitted from close to the black hole and thereby have a new observational test of the central engine. The physics of accretion disks, the astrophysical dynamo, and magnetic reconnection are the least understood physical phenomena in astrophysics. They are still less understood in the general relativity (GR) field close to the black hole. This lack of physical understanding frustrates a quantitative evaluation of observations that define the evolution from the early universe to star formation. We have made progress in this understanding.
Date: December 31, 1998
Creator: Colgate, S.A.; Hills, J.G. & Miller, W.A.
Object Type: Report
System: The UNT Digital Library
Accurate polyatomic quantum dynamics studies of combustion reactions. Final progress report, July 1, 1994--June 30, 1998 (open access)

Accurate polyatomic quantum dynamics studies of combustion reactions. Final progress report, July 1, 1994--June 30, 1998

This program is designed to develop accurate yet practical computational methods, primarily based on time-dependent quantum mechanics, for studying the dynamics of polyatomic reactions beyond the atom-diatom systems. Efficient computational methodologies are developed and the applications of these methods to practical chemical reactions relevant to combustion processes are carried out. The program emphasizes the practical aspects of accurate quantum dynamics calculations in order to understand, explain and predict the dynamical properties of important combustion reactions. The aim of this research is to help provide not only qualitative dynamics information but also quantitative prediction of reaction dynamics of combustion reactions at the microscopic level. Through accurate theoretical calculations, the authors wish to be able to quantitatively predict reaction cross sections and rate constants of relatively small gas-phase reactions from first principles that are of direct interest to combustion. The long-term goal of this research is to develop practical computational methods that are capable of quantitatively predicting dynamics of more complex polyatomic gas-phase reactions that are of interest to combustion.
Date: December 31, 1998
Creator: Zhang, J. Z. H.
Object Type: Report
System: The UNT Digital Library
Actinide biocolloid formation in brine by halophilic bacteria (open access)

Actinide biocolloid formation in brine by halophilic bacteria

The authors examined the ability of a halophilic bacterium (WIPP 1A) isolated from the Waste Isolation Pilot Plant (WIPP) site to accumulate uranium in order to determine the potential for biocolloid facilitated actinide transport. The bacterial cell surface functional groups involved in the complexation of the actinide were determined by titration. Uranium, added as uranyl nitrate, was removed from solution at pH 5 by cells but at pH 7 and 9 very little uranium was removed due to its limited solubility. Although present as soluble species, uranyl citrate at pH 5, 7, and 9, and uranyl carbonate at pH 9 were not removed by the bacterium because they were not bioavailable due to their neutral or negative charge. Addition of uranyl EDTA to brine at pH 5, 7, and 9 resulted in the immediate precipitation of U. Transmission electron microscopy (TEM) and energy dispersive X-ray spectroscopy (EDS) analysis revealed that uranium was not only associated with the cell surface but also accumulated intracellularly as uranium-enriched granules. Extended X-ray absorption fine structure (EXAFS) analysis of the bacterial cells indicated the bulk sample contained more than one uranium phase. Nevertheless these results show the potential for the formation of actinide bearing bacterial …
Date: December 31, 1998
Creator: Gillow, J. B.; Francis, A. J.; Dodge, C. J.; Harris, R.; Beveridge, T. J.; Brady, P. V. et al.
Object Type: Report
System: The UNT Digital Library
Active noise and vibration control for vehicular applications (open access)

Active noise and vibration control for vehicular applications

This is the final report of a one-year, Laboratory Directed Research and Development (LDRD) project at the Los Alamos National Laboratory (LANL). This project investigated semi-active suspension systems based on real time nonlinear control of magneto-rheological (MR) shock absorbers. This effort was motivated by Laboratory interactions with the automobile industry and with the Defense Department. Background research and a literature search on semi-active suspensions was carried out. Numerical simulations of alternative nonlinear control algorithms were developed and adapted for use with an MR shock absorber. A benchtop demonstration system was designed, including control electronics and a mechanical demonstration fixture to hold the damper/spring assembly. A custom-made MR shock was specified and procured. Measurements were carried out at Los Alamos to characterize the performance of the device.
Date: December 31, 1998
Creator: Lewis, P.S. & Ellis, S.
Object Type: Report
System: The UNT Digital Library
Adapting perspectives to facilitate knowledge assimilation (open access)

Adapting perspectives to facilitate knowledge assimilation

The notion of perspective when supported in knowledge representation can allow the representation of multiple and varying points of view, some of which may even be inconsistent with one another. In an object-based knowledge representation methodology created and used by the authors, a perspective is defined by consolidating a number of objects and a number of those objects` associated attributes and methods into a view. This view can help partition a knowledge domain into separate portions. A separate portion represents an individual`s view of the knowledge domain. Representation of multiple and varying perspectives may add to the existing knowledge as well as reveal paths to additional knowledge. A simple example is presented where perspectives are used to represent game playing strategies and levels of expertise in those strategies. Players` perspectives are adapted and changed to provide additional knowledge and insight into further game playing strategies. Results show improvement in the playing of the games. Additionally, a more complex problem for applying these techniques is introduced.
Date: December 31, 1998
Creator: Kelsey, R.L. & Webster, R.B.
Object Type: Article
System: The UNT Digital Library
Adaptive feedforward of estimated ripple improves the closed loop system performance significantly (open access)

Adaptive feedforward of estimated ripple improves the closed loop system performance significantly

The Low Energy Demonstration Accelerator (LEDA) being constructed at Los Alamos National Laboratory will serve as the prototype for the low energy section of Acceleration Production of Tritium (APT) accelerator. This paper addresses the problem of LLRF control system for LEDA. The authors propose an estimator of the ripple and its time derivative and a control law which is based on PID control and adaptive feedforward of estimated ripple. The control law reduces the effect of the deterministic cathode ripple that is due to high voltage power supply and achieves tracking of desired set points.
Date: December 31, 1998
Creator: Kwon, S.; Regan, A.; Wang, Y. M. & Rohlev, T.
Object Type: Article
System: The UNT Digital Library
An adaptive simulation model for analysis of nuclear material shipping operations (open access)

An adaptive simulation model for analysis of nuclear material shipping operations

Los Alamos has developed an advanced simulation environment designed specifically for nuclear materials operations. This process-level simulation package, the Process Modeling System (ProMoS), is based on high-fidelity material balance criteria and contains intrinsic mechanisms for waste and recycle flows, contaminant estimation and tracking, and material-constrained operations. Recent development efforts have focused on coupling complex personnel interactions, personnel exposure calculations, and stochastic process-personnel performance criteria to the material-balance simulation. This combination of capabilities allows for more realistic simulation of nuclear material handling operations where complex personnel interactions are required. They have used ProMoS to assess fissile material shipping performance characteristics at the Los Alamos National Laboratory plutonium facility (TA-55). Nuclear material shipping operations are ubiquitous in the DOE complex and require the largest suite of varied personnel interacting in a well-timed manner to accomplish the task. They have developed a baseline simulation of the present operations and have estimated the operational impacts and requirement of the pit production mission at TA-55 as a result of the SSM-PEIS. Potential bottlenecks have been explored and mechanisms for increasing operational efficiency are identified.
Date: December 31, 1998
Creator: Boerigter, S.T.; Sena, D.J. & Fasel, J.H.
Object Type: Article
System: The UNT Digital Library
Advanced algorithms for information science (open access)

Advanced algorithms for information science

This is the final report of a one-year, Laboratory Directed Research and Development (LDRD) project at Los Alamos National Laboratory (LANL). In a modern information-controlled society the importance of fast computational algorithms facilitating data compression and image analysis cannot be overemphasized. Feature extraction and pattern recognition are key to many LANL projects and the same types of dimensionality reduction and compression used in source coding are also applicable to image understanding. The authors have begun developing wavelet coding which decomposes data into different length-scale and frequency bands. New transform-based source-coding techniques offer potential for achieving better, combined source-channel coding performance by using joint-optimization techniques. They initiated work on a system that compresses the video stream in real time, and which also takes the additional step of analyzing the video stream concurrently. By using object-based compression schemes (where an object is an identifiable feature of the video signal, repeatable in time or space), they believe that the analysis is directly related to the efficiency of the compression.
Date: December 31, 1998
Creator: Argo, P.; Brislawn, C.; Fitzgerald, T.J.; Kelley, B.; Kim, W.H.; Mazieres, B. et al.
Object Type: Report
System: The UNT Digital Library
Advanced buck converter power supply ABCPS for APT (open access)

Advanced buck converter power supply ABCPS for APT

The United States Department of Energy (DOE) is planning to fabricate an Accelerator for the Production of Tritium (APT) at their Savannah River Site, to provide Tritium for national defense. The 1700 million electron volt (MeV) proton beam accelerator will be powered by radio frequency (RF) klystrons. A direct current (DC) power supply is required for each of the approximately two hundred and fifty 1-megawatt (MW) continuous wave klystrons in the RF power system. The requirements are that the power supply meet output performance specifications, provide fault protection for the klystron, have high efficiency, high reliability, good maintainability, and be readily manufacturable. As the power supplies are one of the largest cost elements in the accelerator, a technology review was made to determine the most economical approach to satisfy the requirements. A switch-mode power supply employing a buck-regulator was identified as being potentially the lowest cost approach. As the switch represents a certain development risk, a small-scale prototype has been constructed for evaluation, and has resulted in the decision to fabricate a full-scale prototype power supply. A description of the hardware will be presented.
Date: December 31, 1998
Creator: Street, R.; Overett, T. & Bowles, E.
Object Type: Article
System: The UNT Digital Library
ADVANCED SULFUR CONTROL CONCEPTS FOR HOT GAS DESULFURIZATION TECHNOLOGY (open access)

ADVANCED SULFUR CONTROL CONCEPTS FOR HOT GAS DESULFURIZATION TECHNOLOGY

The objective of this project is to develop a hot-gas desulfurization process scheme for control of H{sub 2}S in HTHP coal gas that can be more simply and economically integrated with known regenerable sorbents in DOE/METC-sponsored work than current leading hot-gas desulfurization technologies. In addition to being more economical, the process scheme to be developed must yield an elemental sulfur byproduct.
Date: December 31, 1998
Creator: unknown
Object Type: Report
System: The UNT Digital Library
Advanced techniques for the analysis of crisis stability, deterrence, and latency (open access)

Advanced techniques for the analysis of crisis stability, deterrence, and latency

This is the final report of a one-year, Laboratory Directed Research and Development (LDRD) project at Los Alamos National Laboratory (LANL). The principal results of studies on crisis stability, deterrence, and latency are presented in their order of development. They capture the main features of stability analysis; relate first strike, crisis, and arms control stability as seen from US and Russian perspective; and address whether different metrics, uncertain damage preferences, or the deployment of defenses can be destabilizing. The report explores differences between unilateral and proportional force reductions in the region of deep reductions where concern shifts from stability to latency.
Date: December 31, 1998
Creator: Canavan, G. H.
Object Type: Report
System: The UNT Digital Library
Advanced telemedicine development (open access)

Advanced telemedicine development

This is the final report of a one-year, Laboratory Directed Research and Development (LDRD) project at the Los Alamos National Laboratory (LANL). The objective of this project was to develop a Java-based, electronic, medical-record system that can handle multimedia data and work over a wide-area network based on open standards, and that can utilize an existing database back end. The physician is to be totally unaware that there is a database behind the scenes and is only aware that he/she can access and manage the relevant information to treat the patient.
Date: December 31, 1998
Creator: Forslund, D.W.; George, J.E. & Gavrilov, E.M.
Object Type: Report
System: The UNT Digital Library
Advanced Turbine System (ATS) program conceptual design and product development. Quarterly report, March 1, 1994--May 31, 1994 (open access)

Advanced Turbine System (ATS) program conceptual design and product development. Quarterly report, March 1, 1994--May 31, 1994

GE has achieved a leadership position in the worldwide gas turbine industry in both industrial/utility markets and in aircraft engines. This design and manufacturing base plus their close contact with the users provides the technology for creation of the next generation advanced power generation systems for both the industrial and utility industries. GE has been active in the definition of advanced turbine systems for several years. These systems will leverage the technology from the latest developments in the entire GE gas turbine product line. These products will be USA based in engineering and manufacturing and are marketed through the GE Industrial and Power Systems. Achieving the advanced turbine system goals of 60% efficiency, 8 ppmvd NO{sub x} and 10% electric power cost reduction imposes competing characteristics on the gas turbine system. Two basic technical issues arise from this. The turbine inlet temperature of the gas turbine must increase to achieve both efficiency and cost goals. However, higher temperatures move in the direction of increased NO{sub x} emission. Improved coating and materials technologies along with creative combustor design can result in solutions to achieve the ultimate goal. GE`s view of the market, in conjunction with the industrial and utility objectives requires …
Date: December 31, 1998
Creator: unknown
Object Type: Report
System: The UNT Digital Library
Aeroelastic behavior of twist-coupled HAWT blades (open access)

Aeroelastic behavior of twist-coupled HAWT blades

As the technology for horizontal axis wind turbines (HAWT) development matures, more novel techniques are required for the capture of additional amounts of energy, alleviation of loads and control of the rotor. One such technique employs the use of an adaptive blade that could sense the wind velocity or rotational speed in some fashion and accordingly modify its aerodynamic configuration to meet a desired objective. This could be achieved in either an active or passive manner, although the passive approach is much more attractive due to its simplicity and economy. As an example, a blade design might employ coupling between bending and/or extension, and twisting so that, as it bends and extends due to the action of the aerodynamic and inertial loads, it also twists modifying the aerodynamic performance in some way. These performance modifications also have associated aeroelastic effects, including effects on aeroelastic instability. To address the scope and magnitude of these effects a tool has been developed for investigating classical flutter and divergence of HAWT blades. As a starting point, an adaptive version of the uniform Combined Experiment Blade will be investigated. Flutter and divergence airspeeds will be reported as a function of the strength of the coupling …
Date: December 31, 1998
Creator: Lobitz, D. W. & Veers, P. S.
Object Type: Article
System: The UNT Digital Library
Aging and PBX 9502 (open access)

Aging and PBX 9502

Components made from PBX 9502, an insensitive high explosive formulated with triaminotrinitrobenzene (TATB) and Kel-F 800 binder, have been in service for nearly two decades. Since that time, samples have been destructively evaluated to determine if potential changes that might affect safety, reliability, or performance have occurred in the high explosive with time. Data from routine, historical testing is reported elsewhere. This paper focuses on specific tests conducted to evaluate the effects of natural aging on handling sensitivity (through the small-scale tests of Human Electrostatic Discharge, friction, and Drop Weight Impact), compressive strength, and thermal ignition. Also reported are the effects of a radiation environment on TATB. Small-scale sensitivity tests show no differences between aged and unaged material. Observed differences in compressive strength behavior are attributed to conditions of original material rather than aging effects. Thermal ignition by flame and laser methods showed no changes between aged and unaged material. Extreme levels of radiation are shown to have only minimal effects in explosive response tests. PBX 9502 is concluded, once again, to be a very stable material, aging gracefully.
Date: December 31, 1998
Creator: Skidmore, C. B.; Idar, D. J.; Buntain, G. A.; Son, S. F. & Sander, R. K.
Object Type: Article
System: The UNT Digital Library
Aging phenomenon in metallic plutonium (open access)

Aging phenomenon in metallic plutonium

Today, as with weapons science issues, the monitoring of plutonium aging becomes an important issue for surveillance. The reasons for this are many-fold. First, and perhaps most important, plutonium is radioactive, primarily through the process of alpha decay. This process has many consequences. One pragmatic one is that the alpha particles ejected near the surface can be used with an ionization gauge-type detector to assess the presence of fine plutonium particulates, allowing plutonium handlers and facilities to detect the presence of contamination in virtual real time. But this alpha decay has other consequences for weapon integrity which are not well known. The same surface alpha particles which allow it`s detection, can also cause a variety of problems with materials which may be found in contact with plutonium over extended time periods. However, when this alpha emission occurs within the bulk of the plutonium metal, it is essentially trapped. Within the metal atom lattice, it acquires valence electrons and becomes a helium atom. At the same time that these helium atoms accumulate within the lattice, atomic displacements and damage to the plutonium lattice occurs due to collisions with the energetic uranium and alpha particles. At the current time, the authors have …
Date: December 31, 1998
Creator: Stevens, M.F. & Martz, J.C.
Object Type: Article
System: The UNT Digital Library
The Albany News (Albany, Tex.), Vol. 123, No. 31, Ed. 1 Thursday, December 31, 1998 (open access)

The Albany News (Albany, Tex.), Vol. 123, No. 31, Ed. 1 Thursday, December 31, 1998

Weekly newspaper from Albany, Texas that includes local, county, and state news along with extensive advertising.
Date: December 31, 1998
Creator: Lucas, Donnie A.
Object Type: Newspaper
System: The Portal to Texas History
Algorithms for a hand-held miniature x-ray fluorescence analytical instrument (open access)

Algorithms for a hand-held miniature x-ray fluorescence analytical instrument

The purpose of this joint program was to provide technical assistance with the development of a Miniature X-ray Fluorescence (XRF) Analytical Instrument. This new XRF instrument is designed to overcome the weaknesses of spectrometers commercially available at the present time. Currently available XRF spectrometers (for a complete list see reference 1) convert spectral information to sample composition using the influence coefficients technique or the fundamental parameters method. They require either a standard sample with composition relatively close to the unknown or a detailed knowledge of the sample matrix. They also require a highly-trained operator and the results often depend on the capabilities of the operator. In addition, almost all existing field-portable, hand-held instruments use radioactive sources for excitation. Regulatory limits on such sources restrict them such that they can only provide relatively weak excitation. This limits all current hand-held XRF instruments to poor detection limits and/or long data collection times, in addition to the licensing requirements and disposal problems for radioactive sources. The new XRF instrument was developed jointly by Quantrad Sensor, Inc., the Naval Research Laboratory (NRL), and the Department of Energy (DOE). This report describes the analysis algorithms developed by NRL for the new instrument and the software …
Date: December 31, 1998
Creator: Elam, W. T.; Newman, D. & Ziemba, F.
Object Type: Report
System: The UNT Digital Library
Alloy design and phase stability of the ternary alloy titanium-aluminum-niobium (open access)

Alloy design and phase stability of the ternary alloy titanium-aluminum-niobium

This is the final report of a three-year, Laboratory Directed Research and Development (LDRD) project at the Los Alamos National Laboratory (LANL). The authors have used high-precision electronic-structure and cluster-variational method (CVM) techniques to study aspects of alloy design involving the phase stability and ordering tendencies of the ternary system Ti-Al-Nb, and the correlation with these to changes in the electronic structure of these materials. This system is of great interest for aerospace applications due to its desirable mechanical properties and low densities. Total energies were computed for 18 binary and ternary bcc superstructures in order to derive parameters for CVM calculations, which showed important strong ordering tendencies in the alloy phase diagram as a function of temperature and alloy concentration. Structural optimization calculations were used to analyze structural instabilities for bcc, fcc, hcp, O-phase, and {omega}-phase structures. The authors discovered the mechanism for the role of Nb in the structural stability of the O-phase of the ternary intermetallic Ti{sub 2}AlNb. Calculations were also done to investigate the electronic properties associated with the structural stability of a related class of Laves Phase high-temperature structural materials NbCr{sub 2} and HfV{sub 2}.
Date: December 31, 1998
Creator: Albers, R. C.; Chen, Shao-Ping & Wills, J. M.
Object Type: Report
System: The UNT Digital Library
Altus Times (Altus, Okla.), Vol. 99, No. 249, Ed. 1 Thursday, December 31, 1998 (open access)

Altus Times (Altus, Okla.), Vol. 99, No. 249, Ed. 1 Thursday, December 31, 1998

Daily newspaper from Altus, Oklahoma that includes local, state, and national news along with advertising.
Date: December 31, 1998
Creator: Cole, Carol
Object Type: Newspaper
System: The Gateway to Oklahoma History
Amended annual report for Brookhaven National Laboratory: Epidemiologic surveillance - 1994 (open access)

Amended annual report for Brookhaven National Laboratory: Epidemiologic surveillance - 1994

Epidemiologic surveillance at DOE facilities consists of regular and systematic collection, analysis, and interpretation of data on absences due to illness and injury in the work force. Its purpose is to provide an early warning system for health problems occurring among employees at participating sites. Data are collected by coordinators at each site and submitted to the Epidemiologic Surveillance Data Center, located at the Oak Ridge Institute for Science and Education, where quality control procedures and analyses are carried out. Rates of absences and rates of diagnoses associated with absences are analyzed by occupation and other relevant variables. They may be compared with the disease experience of different groups within the DOE work force and with populations and do not work for DOE to identify disease patterns or clusters that may be associated work activities. This report provides a final summary for BNL.
Date: December 31, 1998
Creator: unknown
Object Type: Report
System: The UNT Digital Library