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Impact of the LHC beam abort kicker prefire on high luminosity insertion and CMS detector performance (open access)

Impact of the LHC beam abort kicker prefire on high luminosity insertion and CMS detector performance

The effect of possible accidental beam loss in LHC on the IP5 insertion elements and CMS detector is studied via realistic Monte Carlo simulations. Such beam loss could be the consequence of an unsynchronized abort or � in worst case � an accidental prefire of one of the abort kicker modules. Simulations with the STRUCT code show that this beam losses would take place in the IP5 inner and outer triplets. MARS simulations of the hadronic and electro-magnetic cascades induced in such an event indicate severe heating of the inner triplet quadrupoles. In order to protect the IP5 elements, two methods are proposed: a set of shadow collimators in the outer triplet and a prefired module compensation using a special module charged with an opposite voltage (antikicker). The remnants of the accidental beam loss entering the experimental hall have been used as input for FLUKA simulations in the CMS detector. It is shown that it is vital to take measures to reliably protect the expensive CMS tracker components.
Date: April 13, 1999
Creator: A.I. Drozhdin, N.V. Mokhov and M. Huhtinen
Object Type: Article
System: The UNT Digital Library
Test Plan for New SY Farm Annulus Leak Detectors (open access)

Test Plan for New SY Farm Annulus Leak Detectors

This document provides a plan for testing a new annulus leak detection device in the annulus of the waste storage tank 241 SY-102.
Date: August 13, 1999
Creator: ABUNDO, R.
Object Type: Report
System: The UNT Digital Library
Facet Model and Mathematical Morphology for Surface Characterization (open access)

Facet Model and Mathematical Morphology for Surface Characterization

This paper describes an algorithm for the automatic segmentation and representation of surface structures and non-uniformities in an industrial setting. The automatic image processing and analysis algorithm is developed as part of a complete on-line web characterization system of a papermaking process at the wet end. The goal is to: (1) link certain types of structures on the surface of the web to known machine parameter values, and (2) find the connection between detected structures at the beginning of the line and defects seen on the final product. Images of the pulp mixture (slurry), carried by a fast moving table, are obtained using a stroboscopic light and a CCD camera. This characterization algorithm succeeded where conventional contrast and edge detection techniques failed due to a poorly controlled environment. The images obtained have poor contrast and contain noise caused by a variety of sources. After a number of enhancement steps, conventional segmentation methods still f ailed to detect any structures and are consequently discarded. Techniques tried include the Canny edge detector, the Sobel, Roberts, and Prewitt's filters, as well as zero crossings. The facet model algorithm, is then applied to the images with various parameter settings and is found to be …
Date: November 13, 1999
Creator: Abidi, B.R.; Goddard, J.S.; Hunt, M.A. & Sari-Sarraf, H.
Object Type: Article
System: The UNT Digital Library
Corrosion behavior of stainless steel-zirconium alloy waste forms. (open access)

Corrosion behavior of stainless steel-zirconium alloy waste forms.

Stainless steel-zirconium (SS-Zr) alloys are being considered as waste forms for the disposal of metallic waste generated during the electrometallurgical treatment of spent nuclear fuel. The baseline waste form for spent fuels from the EBR-II reactor is a stainless steel-15 wt.% zirconium (SS-15Zr) alloy. This article briefly reviews the microstructure of various SS-Zr waste form alloys and presents results of immersion corrosion and electrochemical corrosion tests performed on these alloys. The electrochemical tests show that the corrosion behavior of SS-Zr alloys is comparable to those of other alloys being considered for the Yucca Mountain geologic repository. The immersion tests demonstrate that the SS-Zr alloys are resistant to selective leaching of fission product elements and, hence, suitable as candidates for high-level nuclear waste forms.
Date: January 13, 1999
Creator: Abraham, D. P.
Object Type: Article
System: The UNT Digital Library
Organization and management of the plant safety evaluation of the VVER-440/230 units at Novovoronezh. (open access)

Organization and management of the plant safety evaluation of the VVER-440/230 units at Novovoronezh.

As part of the Soviet-Designed Reactor Safety (SDRS) element of the International Nuclear Safety Program (INSP), the US Department of Energy (US DOE) is funding a plant safety evaluation (PSE) project for the Novovoronezh Nuclear Power Plant (NvNPP). The Novovoronezh PSE Project is a multi-faceted project with participants from sixteen different international organizations from five different countries scattered across eleven time zones. The purpose of this project is to provide a thorough Probabilistic Risk Analysis (PRA) and Deterministic Safety Analysis (DSA) for Units 3 and 4 of the NvNPP. In addition, this project provides assistance to the operation organizations in meeting their international commitments in support of safety upgrades, and their regulatory requirements for the conduct of safety analyses. Managing this project is a complex process requiring numerous management tools, constant monitoring, and effective communication skills. Employing management tools to resolve unanticipated problems one of the keys to project success. The overall scope, programmatic context, objectives, project interactions, communications, practical hindrances, and lessons learned from the challenging performance of the PSE project are summarized in this paper.
Date: May 13, 1999
Creator: Afshar, C. M.; Pizzica, P.; Puglia, W. J. & Rozin, V.
Object Type: Article
System: The UNT Digital Library
The Oklahoma Daily (Norman, Okla.), Vol. 83, No. 83, Ed. 1 Wednesday, January 13, 1999 (open access)

The Oklahoma Daily (Norman, Okla.), Vol. 83, No. 83, Ed. 1 Wednesday, January 13, 1999

Student newspaper of the University of Oklahoma in Norman, Oklahoma that includes national, local, and campus news along with advertising.
Date: January 13, 1999
Creator: Allam, Heather
Object Type: Newspaper
System: The Gateway to Oklahoma History
The Oklahoma Daily (Norman, Okla.), Vol. 83, No. 139, Ed. 1 Tuesday, April 13, 1999 (open access)

The Oklahoma Daily (Norman, Okla.), Vol. 83, No. 139, Ed. 1 Tuesday, April 13, 1999

Student newspaper of the University of Oklahoma in Norman, Oklahoma that includes national, local, and campus news along with advertising.
Date: April 13, 1999
Creator: Allam, Heather
Object Type: Newspaper
System: The Gateway to Oklahoma History
In situ study of dislocation behavior in columnar Al thin film on Si substrate during thermal cycling (open access)

In situ study of dislocation behavior in columnar Al thin film on Si substrate during thermal cycling

In situ transmission electron microscopy (150 kV) has been employed to study the evolution of dislocation microstructure during relatively rapid thermal cycling of a 200 nm Al thin film on Si substrate. After a few thermal cycles between 150 and 500 C, nearly stable Al columnar grain structure is established with average grain less than a {micro}m. On rapid cooling (3--30+ C/s) from 500 C, dislocations first appear at a nominal temperature of 360--380 C, quickly multiplying and forming planar glide plane arrays on further cooling. From a large number of such experiments the authors have attempted to deduce the dislocation evolution during thermal cycling in these polycrystalline Al films and to account qualitatively for the results on a simple dislocation model.
Date: December 13, 1999
Creator: Allen, C. W.; Schroeder, H. & Hiller, J. M.
Object Type: Article
System: The UNT Digital Library
Dynamic Strain on Thin Diaphragms of a Mercury Target During 800-MeV Proton Thermal Shock Tests (open access)

Dynamic Strain on Thin Diaphragms of a Mercury Target During 800-MeV Proton Thermal Shock Tests

Extrinsic Fabry-Perot Interferometric fiber optic sensors were used to measure dynamic strains on thin diaphragms of a liquid mercury target, which was subjected to intense 800-MeV proton thermal shock tests. The mercury target is engineered with very thin end plates or diaphragms (either 0.6 mm or 1.9 mm) for studying large strain effects. During thermal shock tests, the mercury in the target interacted with an intense pulsed beam of 2.4x10{sup 13 protons}. The resulting pressure waves lead to large strains exceeding 250 microstrains on a 0.6-mm diaphragm. Significant factors relative to the accuracy of strain measurements are emphasized, such as the sensor air gap, alignment of sensors, and frequency response of the strain instrument. In this paper, dynamic strains measured on thin diaphragms are described and discussed.
Date: November 13, 1999
Creator: Allison, S. W.; Andriulli, J. B.; Cates, M. R.; Earl, D. D.; Haines, J. R.; Morrissey, F. X. et al.
Object Type: Article
System: The UNT Digital Library
Certifying the Waste Isolation Pilot Plant: Lessons Learned from the WIPP Experience (open access)

Certifying the Waste Isolation Pilot Plant: Lessons Learned from the WIPP Experience

In May 1998, the US Environmental Protection Agency (EPA) certified the US Department of Energy's (DOE) Waste Isolation Pilot Plant (WIPP) as being in compliance with applicable long-term regulations governing the permanent disposal of spent nuclear fuel, high-level, and transuranic radioactive wastes. The WIPP is the first deep geologic repository in the US to have successfully demonstrated regulatory compliance with long-term radioactive waste disposal requirements. The first disposal of TRU waste at WIPP occurred on March 26, 1999. Many of the lessons learned during the WIPP Project's transition from site characterization and experimental research to the preparation of a successful application may be of general interest to other repository programs. During a four-year period (1992 to 1996), the WIPP team [including the DOE Carlsbad Area Office (CAO), the science advisor to CAO, Sandia National Laboratories (SNL), and the management and operating contractor of the WIPP site, Westinghouse Electric Corporation (WID)] met its aggressive schedule for submitting the application without compromising the integrity of the scientific basis for the long-term safety of the repository. Strong leadership of the CAO-SNL-WID team was essential. Within SNL, a mature and robust performance assessment (PA) allowed prioritization of remaining scientific activities with respect to their …
Date: July 13, 1999
Creator: Anderson, D.R.; Chu, Margaret S.Y.; Froehlich, Gary K.; Howard, Bryan A.; Howarth, Susan M.; Larson, Kurt W. et al.
Object Type: Article
System: The UNT Digital Library
New Pellet Injection Schemes on DIII-D (open access)

New Pellet Injection Schemes on DIII-D

The pellet fueling system on DIII-D has been modified for injection of deuterium pellets from two vertical ports and two inner wall locations on the magnetic high-field side (HFS) of the tokamak. The HFS pellet injection technique was first employed on ASDEX-Upgrade with significant improvements reported in both pellet penetration and fueling efficiency. The new pellet injection schemes on DIII-D required the installation of new guide tubes. These lines are {approx_equal}12.5 m in total length and are made up of complex bends and turns (''roller coaster'' like) to route pellets from the injector to the plasma, including sections inside the torus. The pellet speed at which intact pellets can survive through the curved guide tubes is limited ({approx_equal}200-300 m/s for HFS injection schemes). Thus, one of the three gas guns on the injector was modified to provide pellets in a lower speed regime than the original guns (normal speed range {approx_equal}500 to 1000 m/s). The guide tube installations and gun modifications are described along with the injector operating parameters, and the latest test results are highlighted.
Date: November 13, 1999
Creator: Anderson, P. M.; Baylor, L. R.; Combs, S. K.; Foust, C. R.; Jernigan, T. C. & Robinson, J. I.
Object Type: Article
System: The UNT Digital Library
Feasibility of creating a new liquid surface within waste storage tank 241-SY-101 (open access)

Feasibility of creating a new liquid surface within waste storage tank 241-SY-101

The purpose of this study is to determine the feasibility of creating a new liquid surface within Waste Storage Tank 241-SY-101. This study looked at alternatives for this, as well as providing a summary of observations regarding water lancing results relative to this task.
Date: May 13, 1999
Creator: Andres, B. D.
Object Type: Report
System: The UNT Digital Library
Helicon Plasma Source Configuration Analysis by Means of Density Measurements (open access)

Helicon Plasma Source Configuration Analysis by Means of Density Measurements

Initial results have been obtained from operation of a helicon plasma source built to conduct optimization studies for space propulsion applications. The source features an easily reconfigurable antenna to test different geometries. Operating with He as the source gas, peak densities >= 1.6X10{sup 19} m{sup -3} have been achieved. Radial and axial plasma profiles have been obtained using a microwave interferometer that can be scanned axially and a Langmuir probe. The source will be used to investigate operation at high magnetic field, frequency, and input power.
Date: November 13, 1999
Creator: Angrilli, F.; Barber, G. C.; Carter, M. D.; Goulding, R. H.; Maggiora, R.; Pavarin, D. et al.
Object Type: Article
System: The UNT Digital Library
Radiological Assessment System for Consequence Analysis (RASCAL) Version 3.0 (open access)

Radiological Assessment System for Consequence Analysis (RASCAL) Version 3.0

The Radiological Assessment System for Consequence AnaLysis, Version 3.0 (RASCAL 3.0) is the U.S. Nuclear Regulatory Commission�s (NRC) main computational tool for use during radiological emergencies. RASCAL estimates doses from radiological accidents for comparison with Protective Action Guides and acute health effects thresholds. It includes six computational tools: ST-Dose, FM-Dose, Decay, BackCalc, UF6Plume, and MetProc. ST-Dose computes time-dependent nuclide release rates, atmospheric transport, radiological decay, and doses. FM-Dose computes doses from environmental concentrations of nuclides. Decay computes radiological decay and daughter in-growth. BackCalc estimates a distribution of possible release rates from field measurements. UF6Plume computes uranium exposures and HF concentrations from a UF6 release. MetProc prepares meteorological data for use by ST-Dose and UF6Plume.
Date: September 13, 1999
Creator: Athey, G. F.; Fosmire, C.; Mohseni, A.; Ramsdell, J. V. Jr. & Sjoreen, A.
Object Type: Article
System: The UNT Digital Library
Radio Frequency Plasma Applications for Space Propulsion (open access)

Radio Frequency Plasma Applications for Space Propulsion

Recent developments in solid-state radio frequency (RF) power technologies allow for the practical consideration of RF heated plasmas for space propulsion. These technologies permit the use of any electrical power source, de-couple the power and propellant sources, and allow for the effcient use of both the propellant mass and power. Effcient use of the propellant is obtained by expelling the rocket exhaust at the highest possible velocity, which can be orders of magnitude higher than those achieved in chemical rockets. Handling the hot plasma exhaust requires the use of magnetic nozzles, and the basic physics of ion detachment from the magnetic #12;eld is discussed. The plasma can be generated by RF using helicon waves to heat electrons. Further direct heating of the ions helps to reduce the line radiation losses, and the magnetic geometry is tailored to allow ion cyclotron resonance heating. RF #12;eld and ion trajectory calculations are presented to give a reasonably self-consistent picture of the ion acceleration process.
Date: September 13, 1999
Creator: Baity Jr., F. W.; Barber, G. C.; Carter, M. D.; Chang-Diaz, F. R.; Goulding, R. H.; Ilin, A. V. et al.
Object Type: Article
System: The UNT Digital Library
Corrosion behavior of pyroclore-rich titanate ceramics for plutonium disposition ; impurity effects. (open access)

Corrosion behavior of pyroclore-rich titanate ceramics for plutonium disposition ; impurity effects.

The baseline ceramic contains Ti, U, Ca, Hf, Gd, and Ce, and is made up of only four phases, pyrochlore, zirconolite, rutile, and brannerite. The impurities present in the three other ceramics represent impurities expected in the feed, and result in different phase distributions. The results from 3 day, 90 C MCC-1 tests with impurity ceramics were significantly different than the results from tests with the baseline ceramic. Overall, the addition of impurities to these titanate ceramics alters the phase distributions, which in turn, affects the corrosion behavior.
Date: January 13, 1999
Creator: Bakel, A. J.
Object Type: Article
System: The UNT Digital Library
A microkernel design for component-based parallel numerical software systems. (open access)

A microkernel design for component-based parallel numerical software systems.

What is the minimal software infrastructure and what type of conventions are needed to simplify development of sophisticated parallel numerical application codes using a variety of software components that are not necessarily available as source code? We propose an opaque object-based model where the objects are dynamically loadable from the file system or network. The microkernel required to manage such a system needs to include, at most: (1) a few basic services, namely--a mechanism for loading objects at run time via dynamic link libraries, and consistent schemes for error handling and memory management; and (2) selected methods that all objects share, to deal with object life (destruction, reference counting, relationships), and object observation (viewing, profiling, tracing). We are experimenting with these ideas in the context of extensible numerical software within the ALICE (Advanced Large-scale Integrated Computational Environment) project, where we are building the microkernel to manage the interoperability among various tools for large-scale scientific simulations. This paper presents some preliminary observations and conclusions from our work with microkernel design.
Date: January 13, 1999
Creator: Balay, S.
Object Type: Article
System: The UNT Digital Library
Beam dynamics studies for heavy ion fusion drivers (open access)

Beam dynamics studies for heavy ion fusion drivers

None
Date: April 13, 1999
Creator: Barnard, J.; Celata, C.; Craig, G.; Dehoon, M.; Faltens, A.; Friedman, A. et al.
Object Type: Article
System: The UNT Digital Library
Progress in rapid detection and identification of unknown human and agricultural pathogens (open access)

Progress in rapid detection and identification of unknown human and agricultural pathogens

The medical industry is driving pathogen detection technology from its present characteristics of $50/sample, 100 sample capability systems, with several day time responses, having several percent error rates in reported outcomes. The systems described above are capable of providing samples at < $5/test, managing several million samples, < 1-hour cycle times, (or just minutes in some cases) and < 0.1% error rates. Because of their importance to the medical and agricultural communities, all ''important'' pathogens will have detection kits available (within air transport times, anywhere in the world) by 2020, and the most well known pathogens will have kits available within a few years. Many are available now. Because of the importance of the food supply to modern nations, these technologies will be employed everywhere in this industry. For example, the United States imports 30 B tons of food a year, but inspects < 1%. Portable inspection systems will make it possible to test for dangerous pathogens in feed lots, food processing plants, markets, and points of use. Outbreaks of animal or plant disease will be immediately detectable using field instrumentation, and more complex samples can be sent to central testing laboratories where more sophisticated test systems will be available. …
Date: August 13, 1999
Creator: Barnes, T; Holzrichter, J F & Milanovich, F P
Object Type: Article
System: The UNT Digital Library
Project plan international atomic energy agency (IAEA) safeguards project plutonium finishing plant (open access)

Project plan international atomic energy agency (IAEA) safeguards project plutonium finishing plant

This plan presents the overall objectives, description, justification and planning for the Plutonium Finishing Plant (PFP) International Atomic Energy Agency (IAEA) project. The intent of this plan is to describe how this project will be managed and integrated with other facility stabilization and deactivation activities. This plan supplements the overall integrated plan presented in the PFP Integrated Project Management Plan (PMP), HNF-3617, Rev. 0. This project plan is the top-level definitive project management document for the PFP IAEA project. It specifies the technical, schedule, requirements and the cost baselines to manage the execution of the IAEA project. Any deviations to the document must be authorized through the appropriate change control process.
Date: May 13, 1999
Creator: Bartlett, W. D.
Object Type: Report
System: The UNT Digital Library
Project plan remove special nuclear material from PFP project plutonium finishing plant (open access)

Project plan remove special nuclear material from PFP project plutonium finishing plant

This plan presents the overall objectives, description, justification and planning for the Plutonium Finishing Plant (PFP) Remove Special Nuclear Material (SNM) Materials. The intent of this plan is to describe how this project will be managed and integrated with other facility stabilization and deactivation activities. This plan supplements the overall integrated plan presented in the Plutonium Finishing Plant Integrated Project Management Plan (IPMP), HNF-3617, Rev. 0. This project plan is the top-level definitive project management document for PFP Remove SNM Materials project. It specifies the technical, schedule, requirements and the cost baselines to manage the execution of the Remove SNM Materials project. Any deviations to the document must be authorized through the appropriate change control process.
Date: May 13, 1999
Creator: Bartlett, W. D.
Object Type: Report
System: The UNT Digital Library
Application of RF Power to Plasma Flow Drive in Fusion Confinement (open access)

Application of RF Power to Plasma Flow Drive in Fusion Confinement

Wave induced flows can produce radially sheared velocity profiles that can in turn stabilize drift wave turbulence and improve plasma confinement. A second-order kinetic theory is developed in one-dimensional slab geometry to treat radio frequency (RF)-driven plasma flows. The Vlasov equation is solved to second order in the RF electric field. Moments of the second-order distribution function give time-averaged expressions for the heating rate, the wave kinetic flux, and the RF force exerted on the plasma. On the collisional or transport time scale, the RF force in the poloidal direction is balanced by neoclassical viscosity, and the force in the radial direction is balanced direction by ambipolar electric fields. Comparison is made with previous theories which have relied on incompressible fluid approximations. Very substantial differences are seen in situations involving the Ion Bernstein Wave, a compressional wave.
Date: September 13, 1999
Creator: Batchelor, D. B.; Berry, L. A.; Carter, M. D. & Jaeger, E. F.
Object Type: Article
System: The UNT Digital Library
TEWI Analysis: Its Utility, Its Shortcomings, and Its Results (open access)

TEWI Analysis: Its Utility, Its Shortcomings, and Its Results

The past decade has been a challenging time for the refrigeration and air conditioning industry worldwide. Provisions of the Montreal Protocol and its amendments require the phaseout of chlorofluorocarbon (CFC) and hydrochlorofluorocarbon (HCFC) compounds that have been used extensively as insulating foam blowing agents and refrigerants in refrigeration systems, heat pumps, and air conditioners. In response, hydrofluorocarbon (HFC) compounds were proposed, developed, and are starting to be used as the primary alternatives to CFCs and HCFCs. However, in 1997 under the Kyoto Protocol, industrialized nations have agreed to roll back emissions of HCFCs, carbon dioxide (CO*), and four other greenhouse gases which threaten to cause excessive global warming. The US. Department of Energy and the Alternative Fluorocarbon Environmental Acceptability Study (AFEAS) jointly sponsored research projects to identify the major applications of CFCs, HCFCs, and HFCs and to examine the impacts of these compounds and the energy use of applications employing these compounds on global warming. The five major uses of fluorocarbons based on sales were automobile air conditioning, supermarket refrigeration, unitary heat pumps and air conditioning, chillers for cooling large office buildings, and household refrigeration. Almost all of the refrigerants used in these applications are global warming gases, and if …
Date: September 13, 1999
Creator: Baxter, V.D.; Fischer, S.K. & Sand, J.R.
Object Type: Article
System: The UNT Digital Library
Defense Cleanup and Environmental Programs: Authorization and Appropriations for FY2000 (open access)

Defense Cleanup and Environmental Programs: Authorization and Appropriations for FY2000

Although Congress authorizes most federal programs for multiple years, it annually authorizes programs for national defense as well as appropriating funding for them each fiscal year. Of the activities traditionally authorized and funded, the Department of Defense (DOD) administers the following six environmental programs: environmental restoration, compliance, cleanup at base closure sites, pollution prevention, environmental technology, and natural resource conservation.
Date: December 13, 1999
Creator: Bearden, David M.
Object Type: Report
System: The UNT Digital Library