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A superconducting quadrupole array for transport of multiple high current beams (open access)

A superconducting quadrupole array for transport of multiple high current beams

We present a conceptual design of a superconducting quadrupole magnet array for the side-by-side transport of multiple high current particle beams in induction linear accelerators. The magnetic design uses a modified cosine 20 current distribution inside a square cell boundary. Each interior magnet's neighbors serve as the return flux paths and the poles are placed as close as possible to each other to facilitate this. No iron is present in the basic 2-D magnetic design; it will work at any current level without correction windings. Special 1/8th quadrupoles are used along the transverse periphery of the array to contain and channel flux back into the array, making every channel look as part of an infinite array. This design provides a fixed dimension array boundary equal to the quadrupole radius that can be used for arrays of any number of quadrupole channels, at any field level. More importantly, the design provides magnetic field separation between the array and the induction cores which may be surrounding it. Flux linkage between these two components can seriously affect the operation of both of them.
Date: November 1, 1999
Creator: Faltens, A. & Shuman, D.
System: The UNT Digital Library
Field-Measured Oxidation Rates of Biologically Reduced Selenium in Sludge (open access)

Field-Measured Oxidation Rates of Biologically Reduced Selenium in Sludge

Sludge generated during surface-water transport or biological treatment of selenium laden agricultural drainage water contains high concentrations (20-100 mg/kg) of selenium. Finding safe and economical sludge disposal methods requires understanding of the biogeochemical processes that change selenium speciation (after placed at a disposal site). Two experiments, each comparing 3 treatments for sludge disposal has resulted in data on changes in selenium speciation spanning an eight year period. Treatments included direct application to upland soils and application with tillage to depths of 15 cm and 30 cm. Soil cores, soil water samples and groundwater monitoring were used to track changes in selenium speciation and transport of re-oxidized forms of selenium. Measurements demonstrate the slow re-oxidation of reduced forms of selenium, largely elemental and organically associated forms, to selenate and selenite. Downward transport of these re-oxidized forms of selenium are driven by winter rains. Field measured re-oxidation rates for these field trials are presented and compared to selenium re-oxidation rates in formerly ponded areas at Kesterson Reservoir, California.
Date: May 1, 1999
Creator: Benson, Sally M.; Daggett, John & Zawislansi, Peter
System: The UNT Digital Library
Generating Self-Reliant Teams of Autonomous Cooperating Robots: Desired design Characteristics (open access)

Generating Self-Reliant Teams of Autonomous Cooperating Robots: Desired design Characteristics

The difficulties in designing a cooperative team are significant. Several of the key questions that must be resolved when designing a cooperative control architecture include: How do we formulate, describe, decompose, and allocate problems among a group of intelligent agents? How do we enable agents to communicate and interact? How do we ensure that agents act coherently in their actions? How do we allow agents to recognize and reconcile conflicts? However, in addition to these key issues, the software architecture must be designed to enable multi-robot teams to be robust, reliable, and flexible. Without these capabilities, the resulting robot team will not be able to successfully deal with the dynamic and uncertain nature of the real world. In this extended abstract, we first describe these desired capabilities. We then briefly describe the ALLIANCE software architecture that we have previously developed for multi-robot cooperation. We then briefly analyze the ALLIANCE architecture in terms of the desired design qualities identified.
Date: May 1, 1999
Creator: Parker, L. E.
System: The UNT Digital Library
Heavy ion beams for inertial confinement fusion (open access)

Heavy ion beams for inertial confinement fusion

None
Date: November 1, 1999
Creator: Lee, Edward P.
System: The UNT Digital Library
Evaluation of dynamic target options for dual axis radiography hydrotest facility II (DARHT II) and advanced hydrotest facility (AHF) programs (open access)

Evaluation of dynamic target options for dual axis radiography hydrotest facility II (DARHT II) and advanced hydrotest facility (AHF) programs

Initial results indicate that electron beams hitting targets used to generate x-rays during multipulse operation in advanced radiography facilities will generate plasma plumes which will disturb the electron beam during subsequent pulses. This, in turn, degrades the x-ray spot quality generated by the subsequent pulses. If this concern is substantiated, new facilities such as the Dual Axia Radiography Hydrotest Facility (DARHT II) and the Advanced Hydrotest Facility (AHF) will need a provision for mitigating this effect. one such provision involves moving the target with sufficient velocity that any plasmas formed are carried adequately far from the electron beam that they do not disturb it. They report the various approaches which have been considered and present data showing the maximum target rates which can be achieved with each approach.
Date: March 1, 1999
Creator: Krogh, M; Neurath, R; Sampayan, S & Sanders, D
System: The UNT Digital Library
Cleaning and Decontamination Using Strippable and Protective Coatings at the Idaho National Engineering and Environmental Laboratory (open access)

Cleaning and Decontamination Using Strippable and Protective Coatings at the Idaho National Engineering and Environmental Laboratory

The Idaho National Engineering and Environmental Laboratory (INEEL) Radioactive Liquid Waste Reduction (RLWR) group is conducting a testing and evaluation program on strippable and protective coatings. The purpose of the program is to determine how and where these coatings can be used to aid in the minimization of liquid waste generation. These coatings have become more important in daily operations because of the increased concern of secondary liquid waste generation at the INEEL. Several different strippable and protective coatings were investigated by the RLWR group, including Pentek 604, Bartlett (TLC), and ALARA 1146. During the tests quantitative data was determined, such as effectiveness at reducing contamination levels, or costs, as well as some qualitative data on issues like ease of application or removal. PENTEK 604 and Bartlett TLC are seen as superior products with slightly different uses.
Date: March 1, 1999
Creator: Tripp, J.; Archibald, K.; Lauerhass, L.; Argyle, M. & Demmer, R.
System: The UNT Digital Library
Incoherent effects driven by the electron cloud (open access)

Incoherent effects driven by the electron cloud

As a result of the synchrotron radiation from a positively-charged beam, an electron cloud is expected to develop in the vacuum chamber from the combined effects of the photoelectric and secondary emission processes [1-3]. We provide here a first estimate of the electron-cloud effect on individual particles of the beam. We focus on the space-charge tune spread, the distortion of the beta function and the dispersion, and synchro-betatron coupling. We illustrate the effects with numerical applications to the PEP-II positron ring [4]. We conclude that the magnitude of the effect is not negligible, although it is not large either. However, the present calculations can only be considered as a first estimate, since they do not include details of the electron cloud formation in different regions of the ring.
Date: February 1, 1999
Creator: Furman, M. A. & Zholents, A. A.
System: The UNT Digital Library
Elastic/Plastic Drop Analysis Using Finite Element Techniques (open access)

Elastic/Plastic Drop Analysis Using Finite Element Techniques

A Spent Nuclear Fuel (SNF) can, which is called the High Integrity Can (HIC), is being designed at the Idaho National Engineering and Environmental Laboratory (INEEL). Its intended use is to contain SNF sent to the Idaho Nuclear Technology and Engineering Center (INTEC). INTEC will then do the final work with the HIC to send it to the repository at Yucca Mountain, Nevada, for long-term storage. One portion of the analysis, which was required for the HIC, was accidental drop scenarios. This consisted of 19 simulated drops from a height of 30-feet with impact on a flat rigid surface. Elastic/plastic analyses were performed for the simulated drops. Additionally, two elastic/plastic analyses were performed for drops from a height of 17-feet with impact on a rigid surface having a narrow raised portion across its center. The purpose of the analyses was to determine if any breach occurred which opened a crack wider than 0.05-inches from these drop scenarios. Also some plastic deformations were needed from certain drop scenarios to support the Criticality Safety documentation. The analytical results for the simulated drop scenarios showed that, though the seal in the lid may be broken, no 0.05-inch breach occurred. Also, the deformations for …
Date: August 1, 1999
Creator: Spears, R. E.
System: The UNT Digital Library
Sizing oracle applications projects, a technical perspective (open access)

Sizing oracle applications projects, a technical perspective

None
Date: February 1, 1999
Creator: Rivenes, A
System: The UNT Digital Library
A flexible package and interconnects for microfluidic systems (open access)

A flexible package and interconnects for microfluidic systems

A slide-together compression package and microfluidic interconnects for microfabricated devices requiring fluidic and electrical connections is presented. The package assembles without tools, is reusable, and requires no epoxy, wirebonds, or solder, making chip replacement fast and easy. The microfluidic interconnects use standard HPLC PEEK tubing, with the tip machined to accept either an o-ring or custom molded ring which serves the dual function of forming the seal and providing mechanical retention strength. One design uses a screw to compress the o-ring, while others are simply plugged into a cartridge retained in the package. The connectors are helium leak-tight, can withstand hundreds of psi, are easy to connect and disconnect, are low dead volume, have a small footprint, and are adaptable to a broad range of microfabricated devices.
Date: January 1, 1999
Creator: Benett, W & Krulevitch, P
System: The UNT Digital Library
Design of a TEM waveguide for ultra-wideband applications (open access)

Design of a TEM waveguide for ultra-wideband applications

None
Date: January 1, 1999
Creator: Pao, H Y & Poggio, A
System: The UNT Digital Library
Migrating Relational Data to an ODBMS: Strategies and Lessons from a Molecular Biology Experience (open access)

Migrating Relational Data to an ODBMS: Strategies and Lessons from a Molecular Biology Experience

The growing maturity of ODBMS technology is causing many enterprises to consider migrating relational databases to ODBIMS's. While data remapping is relatively straight-forward in most cases, greater challenges lie in economically and non-invasively adapting legacy application software. We report on a genetics laboratory database migration experiment, which was facilitated by both organization of the relational data in object-like form and a C++-framework designed to insulate application code from relational artifacts. Although this experiment was largely successful, we discovered to our surprise that the framework failed to encapsulate three subtle aspects of the relational implementation, thereby ''contaminating'' application code. We analyze the underlying issues, and offer cautionary guidance to future migrators.
Date: December 1, 1999
Creator: Oler, J.; Lindstrom, G. & Critchlow, T.
System: The UNT Digital Library
Interfacial Friction in Gas-Liquid Annular Flow: Analogies to Full and Transition Roughness (open access)

Interfacial Friction in Gas-Liquid Annular Flow: Analogies to Full and Transition Roughness

New film thickness and pressure gradient data were obtained in a 5.08 by 101.6 mm duct for nitrogen and water in annular flow. Pressures of 3.4 and 17 atm and temperatures of 38 and 93 C were used to vary the gas density and liquid viscosity. These data are used to compute interfacial shear stresses and interfacial friction factors for comparison with several accepted literature correlations. These comparisons are reasonable for small values of the relative film thickness. However, the new data cover conditions not approached by the data used to construct those correlations. By combining the current data with the results of two other comprehensive modern experimental studies, a new correlation for the interfacial friction factor has been developed. This correlation adds elements of transition roughness to Wallis' fully-rough analogy to better predict interfacial friction factors over a wide range of gas Reynolds numbers and liquid film thicknesses.
Date: March 1, 1999
Creator: Bauer, R.C.; Beus, S.G. & Fore, L.B.
System: The UNT Digital Library
Leaking electricity in domestic appliances (open access)

Leaking electricity in domestic appliances

Many types of home electronic equipment draw electric power when switched off or not performing their principal functions. Standby power use (or ''leaking electricity'') for most appliances ranges from 1 - 20 watts. Even though standby use of each device is small, the combined standby power use of all appliances in a home can easily exceed 50 watts. Leaking electricity is already responsible for 5 to 10 percent of residential electricity use in the United States and over 10 percent in Japan. An increasing number of white goods also have standby power requirements. There is a growing international effort to limit standby power to around one watt per device. New and existing technologies are available to meet this target at little or no extra cost.
Date: May 1, 1999
Creator: Meier, Alan & Rosen, Karen
System: The UNT Digital Library
Comparison of Red-Cockaded Woodpecker (Piciodes borealis) Nestling Diet in Old-Growth and Old-Field Longleaf Pine (Pinus palustris) (open access)

Comparison of Red-Cockaded Woodpecker (Piciodes borealis) Nestling Diet in Old-Growth and Old-Field Longleaf Pine (Pinus palustris)

Automatic cameras were used to record adult woodpecker diets in old-growth and old-field longleaf pine in the South. Roaches were the number one prey for the woodpeckers based on either biomass or numbers. The latter ranged from 37% to 57% of the prey numbers and 55%-73% of the biomass. Morisita's index of similarity between old-field and old growth varied from 0.89 to 0.95. The authors conclude that the prey base is similar in both conditions and that old-growth provides similar foraging habitat.
Date: October 1, 1999
Creator: Hanula, J. L. & Engstrom, R. T.
System: The UNT Digital Library
Establishing the Value of Advanced Glazings (open access)

Establishing the Value of Advanced Glazings

Numerous glazing technologies are under development worldwide to improve the performance of building facades. High-performance glazings can provide substantial energy and related environmental benefits, but often at greatly increased first cost when compared to conventional design solutions. To increase market viability, we discuss strategies to reduce the actual and owner-perceived costs associated with developing and producing advanced window systems, specifically switchable electrochromic glazings, and we also suggest marketing strategies designed to appeal to early adopter and mainstream purchasers. These strategies may be applicable to a broad range of advanced glazing materials.
Date: January 1, 1999
Creator: Lee, E & Selkowitz, S.
System: The UNT Digital Library
CDEV-NT: Porting the Control Device Interface to Windows NT (open access)

CDEV-NT: Porting the Control Device Interface to Windows NT

In recent years the rapid increase in processing power of the personal computer has made it a significant competitor to high-end workstations for accelerator control and experimental physics applications. When the decreasing price of the PC and the availability of inexpensive commercial software is also considered, NT becomes a very attractive alternative to traditional UNIX systems. In order to simplify the integration of Personal Computers into our operating environment, we have ported the Control Device (CDEV) Interface to Windows NT. By supporting CDEV on this platform, we can provide routine access to our existing control system. Additionally, CDEV allows us to create an interface from our UNIX workstations to Windows NT applications (such as databases) that are significantly less expensive on the PC. This paper details the pitfalls we encountered during the software migration and will provide a direct comparison between the performance of CDEV applications on UNIX and NT. P articular attention is paid to network performance, which represents most of the overhead of this transition.
Date: October 1, 1999
Creator: Akers, W.; Chen, J. & Watson, C.
System: The UNT Digital Library
Direct chemical oxidation of mixed or toxic wastes (open access)

Direct chemical oxidation of mixed or toxic wastes

Direct Chemical Oxidation (DCO) is an ambient-pressure, low-temperature (<100 C), and aqueous-based process for general-purpose destruction of the organic fraction of hazardous or mixed waste. It uses the peroxydisulfate anion (S{sub 2}O{sub 8}{sup 2{minus}}) in acid or base solutions. The byproduct of the oxidation reaction, typically sodium or ammonium hydrogen sulfate, may be recycled electrolytically to produce the oxidant. The oxidation kinetic reaction is first order with respect to the peroxydisulfate concentration, expressed in equivalents. The rate constant is constant for nearly all dissolved organic compounds: k{sub a} = 0.01 {+-} 0.005 min{sup {minus}1}. This reflects a common rate-determining step, which is the decomposition of the peroxydisulfate anion into the chemically active derivative, the sulfate radical anion, SO{sub 4}{sup {minus}}. This decomposition is promoted in DCO by raising the operating temperature into the range of 80-100 C. Rates are given for approximately 30 substances with diverse functional groups at low concentrations, and for a number of solid and liquid wastes typical of nuclear and chemical industries. The process has been scale up for treatment studies on chlorinated hydrocarbons, in which the hydrolysis of solvent mixtures was followed by oxidation of products in a series of stirred tank reactors. Cost estimates, …
Date: May 1, 1999
Creator: Balazs, G B; Cooper, J F; Farmer, J C & Lewis, P
System: The UNT Digital Library
Reversible (unitized) PEM fuel cell devices (open access)

Reversible (unitized) PEM fuel cell devices

Regenerative fuel cells (RFCs) are enabling for many weight-critical portable applications, since the packaged specific energy (>400 Wh/kg) of properly designed lightweight RFC systems is several-fold higher than that of the lightest weight rechargeable batteries. RFC systems can be rapidly refueled (like primary fuel cells), or can be electrically recharged (like secondary batteries) if a refueling infrastructure is not conveniently available. Higher energy capacity systems with higher performance, reduced weight, and freedom from fueling infrastructure are the features that RFCs promise for portable applications. Reversible proton exchange membrane (PEM) fuel cells, also known as unitized regenerative fuel cells (URFCs), or reversible regenerative fuel cells, are RFC systems which use reversible PEM cells, where each cell is capable of operating both as a fuel cell and as an electrolyzer. URFCs further economize portable device weight, volume, and complexity by combining the functions of fuel cells and electrolyzers in the same hardware, generally without any system performance or efficiency reduction. URFCs are being made in many forms, some of which are already small enough to be portable. Lawrence Livermore National Laboratory (LLNL) has worked with industrial partners to design, develop, and demonstrate high performance and high cycle life URFC systems. LLNL is …
Date: June 1, 1999
Creator: Mitlitsky, F.; Myers, B.; Smith, W. F. & Weisberg, Molter, T. M.
System: The UNT Digital Library
Vacuum simulation of RF cavities to optimize pump configurations (open access)

Vacuum simulation of RF cavities to optimize pump configurations

The pressure history in the components of an rf linac has been modeled using Mathematica.[1] Specifically the Cavity Coupled Drift Tube Linac (CCDTL) and Cavity Coupled Linac (CCL) sections of the Accelerator Production of Tritium (APT) plant [2] have been modeled in order to predict the optimal pump configuration over the 224 meter length. The pressure history in up to 43 sub-volumes within three representative modules (about three meters long) is analyzed in detail. Included in our model are time-dependent outgassing rates and pressure-dependent pump speeds. With this information, we solve for the pressure history during roughing and with turbo and ion pumps. The number and size of each pump is optimized to achieve the desired pressure with minimal costs.
Date: March 1, 1999
Creator: Shen, S. & Tung, L. S.
System: The UNT Digital Library
Remote Underwater Characterization System - Innovative Technology Summary Report (open access)

Remote Underwater Characterization System - Innovative Technology Summary Report

Characterization and inspection of water-cooled and moderated nuclear reactors and fuel storage pools requires equipment capable of operating underwater. Similarly, the deactivation and decommissioning of older nuclear facilities often requires the facility owner to accurately characterize underwater structures and equipment which may have been sitting idle for years. The Remote Underwater Characterization System (RUCS) is a small, remotely operated submersible vehicle intended to serve multiple purposes in underwater nuclear operations. It is based on the commercially-available �Scallop� vehicle 1 , but has been modified by the Department of Energy�s Robotics Technology Development Program to add auto-depth control, and vehicle orientation and depth monitoring at the operator control panel. The RUCS is designed to provide visual and gamma radiation characterization, even in confined or limited access areas. It was demonstrated in August 1998 at the Idaho National Engineering and Environmental Laboratory (INEEL) as part of the INEEL Large Scale Demonstration and Deployment Project. During the demonstration it was compared in a "head-to-head� fashion with the baseline characterization technology. This paper summarizes the results of the demonstration and lessons learned; comparing and contrasting both technologies in the areas of cost, visual characterization, radiological characterization, and overall operations.
Date: April 1, 1999
Creator: Willis, W. D.
System: The UNT Digital Library
Mechanical design of the VISA undulator (open access)

Mechanical design of the VISA undulator

As part of the research and development effort for a 4th generation light source, we have designed a 4-meter long Free-Electron Laser (FEL) undulator. The undulator will be installed at the Accelerator Test Facility (ATF) at Brookhaven National Laboratory to conduct a Self-Amplified Spontaneous Emission (SASE) demonstration. The demonstration is called VISA, which stands for �Visible to Infrared SASE Amplifier.� The undulator consists of 440 permanent dipole magnets per meter which are supported and aligned on a precision strongback. Focusing and defocusing permanent quadrupole magnets are also supported by the strongback. Each of the 4 one-meter sections of undulator are kinematically supported and housed within the vacuum vessel. The undulator and the vacuum vessel are supported independently to eliminate undulator misalignment during vacuum pump-down of the vessel. We describe the design requirements and features of the undulator, vacuum vessel and support system.
Date: March 1, 1999
Creator: Bertolini, L; Carr, R; Duffy, P; Libkind, M; Ratowsky, G & Skarita, J
System: The UNT Digital Library
Integration of Environmental Restoration and Decontamination and Dismantlement Requirements at the INEEL (open access)

Integration of Environmental Restoration and Decontamination and Dismantlement Requirements at the INEEL

In 1997, the Environmental Restoration Program at the Idaho National Engineering and Environmental Laboratory (INEEL) determined that it was necessary to remediate a Comprehensive Environmental Response and Liability Act (CERCLA) site to address the risk of subsurface petroleum contamination to human health and the environment. This cleanup project was conducted utilizing the Non-time Critical Removal Action process. Due to the close proximity (above the contaminated soil) of a number of above ground storage tanks and a building, the CERCLA project team worked closely with the D&D group to ensure all requirements for each program were met. Lessons learned and regulatory requirements are discussed in the paper, including the factors unknown to many ER personnel regarding the steps required to be completed prior to the dismantlement of structures. The paper summarizes the background associated with the site, why the removal action was conducted, the scope of the removal action, and the results. The emphasis of the paper is to discuss the integration between ER and D&D requirements and processes. In the current environment where ER and D&D activities are commingled, it is imperative that ER and D&D personnel are aware of the requirements imposed upon each program. By working together and …
Date: February 1, 1999
Creator: Reese, C. L. & Kuhns, D. J.
System: The UNT Digital Library
Directions for advanced use of nuclear power in century XXI (open access)

Directions for advanced use of nuclear power in century XXI

Nuclear power can provide a significant contribution to electricity generation and meet other needs of the world and the US during the next century provided that certain directions are taken to achieve its public acceptance. These directions include formulation of projections of population, energy consumption, and energy resources over a responsible period of time. These projections will allow assessment of cumulative effects on the environment and on fixed resources. Use of fossil energy resources in a century of growing demand for energy must be considered in the context of long-term environmental damage and resource depletion. Although some question the validity of these consequences, they can be mitigated by use of advanced fast reactor technology. It must be demonstrated that nuclear power technology is safe, resistant to material diversion for weapon use, and economical. An unbiased examination of all the issues related to energy use, especially of electricity, is an essential direction to take.
Date: May 1, 1999
Creator: Walter, C E
System: The UNT Digital Library