Transformation as a Design Process and Runtime Architecture for High Integrity Software (open access)

Transformation as a Design Process and Runtime Architecture for High Integrity Software

We have discussed two aspects of creating high integrity software that greatly benefit from the availability of transformation technology, which in this case is manifest by the requirement for a sophisticated backtracking parser. First, because of the potential for correctly manipulating programs via small changes, an automated non-procedural transformation system can be a valuable tool for constructing high assurance software. Second, modeling the processing of translating data into information as a, perhaps, context-dependent grammar leads to an efficient, compact implementation. From a practical perspective, the transformation process should begin in the domain language in which a problem is initially expressed. Thus in order for a transformation system to be practical it must be flexible with respect to domain-specific languages. We have argued that transformation applied to specification results in a highly reliable system. We also attempted to briefly demonstrate that transformation technology applied to the runtime environment will result in a safe and secure system. We thus believe that the sophisticated multi-lookahead backtracking parsing technology is central to the task of being in a position to demonstrate the existence of HIS.
Date: April 5, 1999
Creator: Bespalko, Stephen J. & Winter, Victor L.
Object Type: Article
System: The UNT Digital Library
Low VOC drying of lumber and wood panel products. Progress report Number 9 (open access)

Low VOC drying of lumber and wood panel products. Progress report Number 9

Results from a multi-year study show that a significant part of the extensive variability observed in oriented strand board (OSB) flake dryer emissions can be traced to physiological effects, and the rest can be attributed to handling and other factors. Low-headspace treatment of lumber was scaled up to the 50 kg level. The amount of turpentine collected was of the same magnitude as that released upon drying lumber. For the process to be economical, the wood must first be brought to about 95 C with steam, and then processed with RF. Attempts to remove VOCs from OSB through low-headspace by placing a curtain over the wood failed because of leaks. A more rigid container will be required. RF-treatment does not alter the gas permeability of lumber.
Date: January 1, 1999
Creator: Yan, H.; Banerjee, S.; Conners, T.; Ingram, L. L.; Dalton, A. T.; Templeton, M. C. et al.
Object Type: Report
System: The UNT Digital Library
Near-infrared spectroscopy. Innovative technology summary report (open access)

Near-infrared spectroscopy. Innovative technology summary report

A near-infrared (NIR) spectroscopy system with a remote fiber-optic probe was developed and demonstrated to measure the water content of high-level radioactive wastes from the underground storage tanks at the Hanford Site in richland Washington. The technology was developed as a cost-effective and safer alternative to the thermogravimetric analysis (TGA) technique in use as the baseline. This work was supported by the Tanks Focus Area (TFA) within the Department of Energy`s (DOE) Office of Science and Technology (OST) in cooperation with the Hanford Tank Waste Remediation System (TWRS) Program.
Date: July 1, 1999
Creator: unknown
Object Type: Report
System: The UNT Digital Library
Vitrification of ion exchange materials. Innovative technology summary report (open access)

Vitrification of ion exchange materials. Innovative technology summary report

Ion exchange is a process that safely and efficiently removes radionuclides from tank waste. Cesium and strontium account for a large portion of the radioactivity in waste streams from US Department of Energy (DOE) weapons production. Crystalline silicotitanate (CST) is an inorganic sorbent that strongly binds cesium, strontium, and several other radionuclides. Developed jointly by Sandia National Laboratory and Texas A and M University, CST was commercialized through a cooperative research and development agreement with an industrial partner. Both an engineered (mesh pellets) and powdered forms are commercially available. Cesium removal is a baseline in HLW treatment processing. CST is very effective at removing cesium from HLW streams and is being considered for adoption at several sites. However, CST is nonregenerable, and it presents a significant secondary waste problem. Treatment options include vitrification of the CST, vitrification of the CST coupled with HLW, direct disposal, and low-temperature processes such as grouting. The work presented in this report demonstrates that it is effective to immobilize CST using a baseline technology such as vitrification. Vitrification produces a durable waste form. CST vitrification was not demonstrated before 1996. In FY97, acceptable glass formulations were developed using cesium-loaded CST obtained from treating supernatants from …
Date: July 1, 1999
Creator: unknown
Object Type: Report
System: The UNT Digital Library
Fusion technology development: Annual report, October 1, 1997--September 30, 1998 (open access)

Fusion technology development: Annual report, October 1, 1997--September 30, 1998

The overall objective of the General Atomics (GA) fusion technology development program is the advancement of the knowledge base needed for next-generation fusion experiments, and ultimately for an economical and environmentally attractive fusion energy source. To achieve this objective, the authors carry out fusion systems design studies to evaluate the technologies and materials needed for next-step experiments and power plants, and they conduct research to develop basic and applied knowledge about these materials and technologies. GA`s fusion technology development program derives from, and draws on, the physics and engineering expertise built up by many years of experience in designing, building, and operating plasma physics experiments. The technology development activities take full advantage of the current DIII-D program and facility. The following sections summarize GA`s FY98 work done in the areas of Fusion Power Plan Design Studies (Section 2), Plasma Interactive Materials (Section 3), Radiation Testing of ITER Magnetic Coil (Section 4), RF Technology (Section 5), Advanced Liquid Plasma Facing Surfaces (Section 6), and Advanced Power Extraction Study (Section 7). The work in these areas continues to address many of the issues that must be resolved for the successful construction and operation of next-generation experiments and, ultimately, the development of safe, …
Date: June 1, 1999
Creator: unknown
Object Type: Report
System: The UNT Digital Library
DOE standard: Radiological control (open access)

DOE standard: Radiological control

The Department of Energy (DOE) has developed this Standard to assist line managers in meeting their responsibilities for implementing occupational radiological control programs. DOE has established regulatory requirements for occupational radiation protection in Title 10 of the Code of Federal Regulations, Part 835 (10 CFR 835), ``Occupational Radiation Protection``. Failure to comply with these requirements may lead to appropriate enforcement actions as authorized under the Price Anderson Act Amendments (PAAA). While this Standard does not establish requirements, it does restate, paraphrase, or cite many (but not all) of the requirements of 10 CFR 835 and related documents (e.g., occupational safety and health, hazardous materials transportation, and environmental protection standards). Because of the wide range of activities undertaken by DOE and the varying requirements affecting these activities, DOE does not believe that it would be practical or useful to identify and reproduce the entire range of health and safety requirements in this Standard and therefore has not done so. In all cases, DOE cautions the user to review any underlying regulatory and contractual requirements and the primary guidance documents in their original context to ensure that the site program is adequate to ensure continuing compliance with the applicable requirements. To assist …
Date: July 1, 1999
Creator: unknown
Object Type: Report
System: The UNT Digital Library
In situ bioremediation for the Hanford carbon tetrachloride plume. Innovative technology summary report (open access)

In situ bioremediation for the Hanford carbon tetrachloride plume. Innovative technology summary report

The 200 Area at Hanford (also called the Central Plateau) contains approximately 817 waste sites, 44 facilities to be demolished, and billions of gallons of contaminated groundwater resulting from chemical processing plants and associated waste facilities (e.g., waste tanks). From 1955 to 1973, carbon tetrachloride, nitrate, and other materials were discharged to subsurface liquid waste disposal facilities in the 200 Area. As much as 600,000 kilograms of carbon tetrachloride may have entered the soil column and a portion of this has contaminated the underlying aquifer. In Situ Bioremediation for the Hanford Carbon Tetrachloride Plume (ISB), which is the term used in this report for an in situ treatment process using indigenous micro-organisms with a computer based Accelerated Bioremediation Design Tool (ABDT), remediates groundwater contaminated with volatile organic compounds (VOCs) and nitrates under anaerobic conditions. ISB involves the injection of nutrients into the groundwater and subsequent extraction and re-injection of the groundwater to provide nutrient distribution in the aquifer.
Date: April 1, 1999
Creator: unknown
Object Type: Report
System: The UNT Digital Library
Directory of awardee names (open access)

Directory of awardee names

Standardization of grant and contract awardee names has been an area of concern since the development of the Department`s Procurement and Assistance Data System (PADS). A joint effort was begun in 1983 by the Office of Scientific and Technical Information (OSTI) and the Office of Procurement and Assistance Management/Information Systems and Analysis Division to develop a means for providing uniformity of awardee names. As a result of this effort, a method of assigning vendor identification codes to each unique awardee name, division, city, and state combination was developed and is maintained by OSTI. Changes to vendor identification codes or awardee names contained in PADS can be made only by OSTI. Awardee names in the Directory indicate that the awardee has had a prime contract (excluding purchase orders of $10,000 or less) with, or a financial assistance award from, the Department. Award status--active, inactive, or retired--is not shown. The Directory is in alphabetic sequence based on awardee name and reflects the OSTI-assigned vendor identification code to the right of the name. A vendor identification code is assigned to each unique awardee name, division, city, and state (for place of performance). The same vendor identification code is used for awards throughout the …
Date: July 1, 1999
Creator: unknown
Object Type: Report
System: The UNT Digital Library
Centrifugal shot blasting. Innovative technology summary report (open access)

Centrifugal shot blasting. Innovative technology summary report

At the US Department of Energy (DOE) Fernald Environmental Management Project (FEMP), the Facilities Closure and Demolition Projects Integrated Remedial Design/Remedial Action (RD/RA) work plan calls for the removal of one inch (1 in) depth of concrete surface in areas where contamination with technetium-99 has been identified. This report describes a comparative demonstration between two concrete removal technologies: an innovative system using Centrifugal Shot Blasting (CSB) and a modified baseline technology called a rotary drum planer.
Date: July 1, 1999
Creator: unknown
Object Type: Report
System: The UNT Digital Library
Pipe Explorer{trademark} surveying system. Innovative technology summary report (open access)

Pipe Explorer{trademark} surveying system. Innovative technology summary report

The US Department of Energy`s (DOE) Chicago Operations Office and the DOE`s Federal Energy Technology Center (FETC) developed a Large Scale Demonstration Project (LSDP) at the Chicago Pile-5 Research Reactor (CP-5) at Argonne National Laboratory-East (ANL). The objective of the LSDP is to demonstrate potentially beneficial decontamination and decommissioning (D and D) technologies in comparison with current baseline technologies. The Pipe Explorer{trademark} system was developed by Science and Engineering Associates, Inc. (SEA), Albuquerque, NM as a deployment method for transporting a variety of survey tools into pipes and ducts. Tools available for use with the system include alpha, beta and gamma radiation detectors; video cameras; and pipe locator beacons. Different versions of this technology have been demonstrated at three other sites; results of these demonstrations are provided in an earlier Innovative Technology Summary Report. As part of a D and D project, characterization radiological contamination inside piping systems is necessary before pipes can be recycled, remediated or disposed. This is usually done manually by surveying over the outside of the piping only, with limited effectiveness and risk of worker exposure. The pipe must be accessible to workers, and embedded pipes in concrete or in the ground would have to be …
Date: June 1, 1999
Creator: unknown
Object Type: Report
System: The UNT Digital Library
Position-sensitive radiation monitoring (surface contamination monitor). Innovative technology summary report (open access)

Position-sensitive radiation monitoring (surface contamination monitor). Innovative technology summary report

The Shonka Research Associates, Inc. Position-Sensitive Radiation Monitor both detects surface radiation and prepares electronic survey map/survey report of surveyed area automatically. The electronically recorded map can be downloaded to a personal computer for review and a map/report can be generated for inclusion in work packages. Switching from beta-gamma detection to alpha detection is relatively simple and entails moving a switch position to alpha and adjusting the voltage level to an alpha detection level. No field calibration is required when switching from beta-gamma to alpha detection. The system can be used for free-release surveys because it meets the federal detection level sensitivity limits requires for surface survey instrumentation. This technology is superior to traditionally-used floor contamination monitor (FCM) and hand-held survey instrumentation because it can precisely register locations of radioactivity and accurately correlate contamination levels to specific locations. Additionally, it can collect and store continuous radiological data in database format, which can be used to produce real-time imagery as well as automated graphics of survey data. Its flexible design can accommodate a variety of detectors. The cost of the innovative technology is 13% to 57% lower than traditional methods. This technology is suited for radiological surveys of flat surfaces at …
Date: June 1, 1999
Creator: unknown
Object Type: Report
System: The UNT Digital Library
Innovative directional and position specific sampling technique (POLO). Innovative technology summary report (open access)

Innovative directional and position specific sampling technique (POLO). Innovative technology summary report

The UTD Inc. Position Location (POLO) device is used for identifying the position of characterization sensors in the subsurface. POLO fits within a cone penetrometer rod to quickly and cost-effectively identify sample location, rod tip location, and track the rod path. UTD demonstrated the POLO device at a private site in Virginia and at the DOE Savannah River Site in South Carolina. Results show POLO as accurate as any alternative approach at less than 0.50% error, and at a fraction of the cost. POLO can be used in close proximity to tanks, pipelines, and buildings with greatly reduced risk of puncture and resulting spills--a major improvement over current approaches. POLO only adds about 4% to cost of penetrometer use.
Date: June 1, 1999
Creator: unknown
Object Type: Report
System: The UNT Digital Library
High-precision reflectometry of multilayer coatings for extreme ultraviolet lithography (open access)

High-precision reflectometry of multilayer coatings for extreme ultraviolet lithography

Synchrotron-based reflectometry is an important technique for the precise determination of optical properties of reflective multilayer coatings for Extreme Ultraviolet Lithography (EUVL). Multilayer coatings enable normal incidence reflectances of more than 65% in the wavelength range between 11 and 15 nm. In order to achieve high resolution and throughput of EUVL systems, stringent requirements not only apply to their mechanical and optical layout, but also apply to the optical properties of the multilayer coatings. Therefore, multilayer deposition on near-normal incidence optical surfaces of projection optics, condenser optics and reflective masks requires suitable high-precision metrology. Most important, due to their small bandpass on the order of only 0.5 nm, all reflective multilayer coatings in EUVL systems must be wavelength-matched to within {+-}0.05 nm. In some cases, a gradient of the coating thickness is necessary for wavelength matching at variable average angle of incidence in different locations on the optical surfaces. Furthermore, in order to preserve the geometrical figure of the optical substrates, reflective multilayer coatings need to be uniform to within 0.01 nm in their center wavelength. This requirement can only be fulfilled with suitable metrology, which provides a precision of a fraction of this value. In addition, for the detailed …
Date: December 29, 1999
Creator: Wedowski, M; Underwood, J H; Gullikson, E M; Bajt, S; Folta, J A; Kearney, P A et al.
Object Type: Article
System: The UNT Digital Library
Water-Level Monitoring Plan for the Hanford Groundwater Monitoring Project (open access)

Water-Level Monitoring Plan for the Hanford Groundwater Monitoring Project

This document presents the water-level monitoring plan for the Hanford Groundwater Monitoring Project, conducted by the Pacific Northwest National Laboratory (PNNL). Water-level monitoring of the groundwater system beneath the Hanford Site is performed to fulfill the requirements of various state and federal regulations, orders, and agreements. The primary objective of this monitoring is to determine groundwater flow rates and directions. To meet this and other objectives, water-levels are measured annually in monitoring wells completed within the unconfined aquifer system, the upper basalt-confined aquifer system, and in the lower basalt-confined aquifers for surveillance monitoring. At regulated waste units, water levels are taken monthly, quarterly, semi-annually, or annually, depending on the hydrogeologic conditions and regulatory status of a given site. The techniques used to collect water-level data are described in this document, along with the factors that affect the quality of the data and the strategies employed by the project to minimize error in the measurement and interpretation of water levels.
Date: September 7, 1999
Creator: McDonald, John P.; Chamness, Michele A. & Newcomer, Darrell R.
Object Type: Report
System: The UNT Digital Library
Structural analyses of the storage container for heavy element facility, building-251 (open access)

Structural analyses of the storage container for heavy element facility, building-251

The Heavy Element Facility, Building 251, contains a series of underground storage vaults which are used for long term storage of nuclear materials. A storage rack with shelves is suspended from the top of each storage vault. The stainless steel containers enclosing the nuclear materials are stored on the shelves. A Hazard & Accident assessment analyzed the vulnerability of this storage system to assaults resulting from natural phenomena and accidents within the building. The assessment considered all racks and their containers to be stored underground and secured in their static, long-term configuration. Moving beyond the static, long-term hazard assessment, the structural analyses were performed to evaluate the storage container against a rare, short duration event. An accidental free drop of a container may occur in a combination of two events: a rare, short-duration earthquake concurrent with an operation of raising the storage rack to a maximum height that the crane is capable of. This hypothetical free drop may occur only to the container in the uppermost shelf of the storage rack. The analyses were the structural evaluation of the storage container to determine the material containment integrity of the storage container after the accident. The evaluation was performed simulating a …
Date: January 1, 1999
Creator: Ng, D S
Object Type: Report
System: The UNT Digital Library
Energy Payback: Clean Energy from PV; National Center for Photovoltaics PV FAQs (Fact Sheet) (open access)

Energy Payback: Clean Energy from PV; National Center for Photovoltaics PV FAQs (Fact Sheet)

This FAQ sheet discusses the concept of ''energy payback,'' or how long a PV system must operate to recover the energy -- and associated generation of pollution and carbon dioxide -- that went into making the system in the first place. Energy payback estimates for rooftop PV systems boil down to 4, 3, 2, and 1 years: 4 years for systems using current multicrystalline-silicon PV modules, 3 years for current thin-film modules, 2 years for future multicrystalline modules, and 1 year for future thin-film modules. With energy paybacks of 1-4 years and assumed life expectancies of 30 years, 87% to 97% of the energy that PV systems generate will be free of pollution, greenhouse gases, and depletion of resources.
Date: June 1, 1999
Creator: unknown
Object Type: Text
System: The UNT Digital Library
PNNL/Euratom Glass Fiber Optic, Spent Fuel Neutron Profile Measurement System (open access)

PNNL/Euratom Glass Fiber Optic, Spent Fuel Neutron Profile Measurement System

PNNL/Euratom Glass Fiber Optic, Spent Fuel Neutron Profile Measurement System
Date: September 29, 1999
Creator: Bowyer, Sonya M. & Smart, John E.
Object Type: Report
System: The UNT Digital Library
Gold Beam Losses at the AGS Booster Injection. (open access)

Gold Beam Losses at the AGS Booster Injection.

Gold beam injection efficiency decreases in proportional to the beam loss in the AGS Booster. A close look shows that large number of electrons, ions, and neutral particles are created when the gold beam scrapes wall. To investigate the neutral particle production due to the beam loss, local vacuum measurement was made during the 1998 run. It shows that the pressure created by the Booster Au{sup 31+} beam loss at injection has a 35 ms decay time constant. The beam loss created pressure bump in the ring is about 20 meters long. When 3 x 10{sup 9} Gold ions scrapes wall, a pressure higher than 10{sup -7} Torr was created. The beam lifetime calculated using these parameters is in agreement with the observed one.
Date: March 29, 1999
Creator: Zhang, S. Y. & Ahrens, L. A.
Object Type: Article
System: The UNT Digital Library
Solar Success Story at Moanalua Terrace (open access)

Solar Success Story at Moanalua Terrace

Solar systems prove to be the environmentally and economically sound choice for heating water in U.S. Navy housing at Moanalua Terrace in Pearl Harbor, Hawaii. Hawaii is a perfect environment for solar water heating,'' according to Alan Ikeda, a Housing Management Specialist with the Pacific Naval Facility Engineering Command Housing Department in Pearl Harbor, Hawaii. ''The sun shines most of the time, we don't have to worry about freezing, the state offers a 35% solar tax credit, and our local utility supports the purchase and installation of solar systems with generous rebates.'' The Hawaiian Electric Company's (HECO's) $1,500 per unit rebate for solar water heaters installed on new construction helped persuade the Navy to take advantage of Hawaii's solar resource and install solar water heaters on family housing units. At Moanalua Terrace, the Navy had demolished 752 units of family housing, which they are rebuilding in four phases. Designers decided to use the opportunity to give the solar systems a try. When the 100 homes in Phase I were built, money was not available for solar water heaters. However, Ikeda subsequently secured a $130,000 grant from the U.S. Department of Energy's (DOE's) Federal Energy Management Program (FEMP) to retrofit the …
Date: March 1, 1999
Creator: unknown
Object Type: Text
System: The UNT Digital Library
A Cupronickel Rotating Band Pion Production Target for Muon Colliders. (open access)

A Cupronickel Rotating Band Pion Production Target for Muon Colliders.

A conceptual design is presented for a high power cupronickel pion production target. It forms a circular band in a horizontal plane with approximate dimensions of: 2.5 meters radius, 6 cm high and 0.6 cm thick. The target is continuously rotated at 3 m/s to carry heat away from the production region to a water cooling channel. Bunches of 16 GeV protons with total energies of 270 kl and repetition rates of 15 Hz are incident tangentially to arc of the target along the symmetry axis of a 20 Tesla solenoidal magnetic capture channel. The mechanical layout and cooling setup are described. Results are presented from realistic MARS Monte Carlo computer simulations of the pion yield and energy deposition in the target. ANSYS finite element calculations are beginning to give predictions for the resultant shock heating stresses.
Date: March 29, 1999
Creator: King, B. J.; Weggel, R. J.; Mokhov, N. V. & Moser, S. S.
Object Type: Article
System: The UNT Digital Library
Investigation of in situ hydrothermal oxidative destruction of NDMA (open access)

Investigation of in situ hydrothermal oxidative destruction of NDMA

Rate constants for the aqueous oxidation of N-nitrosodimethylamine (NDMA) have been measured in aqueous phosphate-buffered solutions using Dickson-type vessels. The initial NDMA concentrations ranged from 2.5 to 2.8 ppm and reaction temperatures varied from 180 C to 220 C. Quantitation of NDMA was performed by gas chromatography-mass spectrometry (GC-MS) using selected ion monitoring (SIM). NDMA loss with concomitant production of nitrite and nitrate confirmed that mineralization of NDMA occurred, and no intermediates amenable to GC-MS were formed during the oxidation experiments. First order reaction rate constants for the loss of NDMA were determined by the integral method and the results are as follows: k{sub 1} = 5.21 x 10{sup -7} s{sup -1} at 180 C, k{sub 1} = 1.14 x 10{sup -6} s{sup -1} at 190 C, k{sub 1} = 2.05 x 10{sup -6} s{sup -1} at 200 C, k{sub 1} = 4.53 x 10{sup -6} s{sup -1} at 210 C and k{sub 1} = 8.81 x 10{sup -6} s{sup -1} at 220 C. The Arrhenius equation for this data is listed below: ln (k) = 20.21 - 15716 (1/T). The activation energy for this process is calculated to be 130.7 {+-} 3.5 kJ/mole. Extrapolating to a temperature of 125 …
Date: February 25, 1999
Creator: Leif, R N; Knauss, K G & Aines, R D
Object Type: Report
System: The UNT Digital Library
Search for Squarks and Gluinos in Events Containing Jets and a Large Imbalance in Transverse Energy (open access)

Search for Squarks and Gluinos in Events Containing Jets and a Large Imbalance in Transverse Energy

Using data corresponding to an integrated luminosity of 79 pb{sup -1}, D0 has searched for events containing multiple jets and large missing transverse energy in p{bar p} collisions at {radical}s = 1.8 TeV at the Fermilab Tevatron collider. Observing no significant excess beyond what is expected from the standard model, they set limits on the masses of squarks and gluinos and on the model parameters m{sub 0} and m{sub 1/2}, in the framework of the minimal low-energy supergravity models of supersymmetry. For tan {beta} = 2 and A{sub 0} = 0, with {mu} < 0, they exclude all models with m{sub q} {approx} < 250 GeV/c{sup 2}. For models with equal squark and gluino masses, they exclude m < 260 GeV/c{sup 2}.
Date: February 1, 1999
Creator: Abbott, B.; Abolins, M.; Abramov, V.; Acharya, B. S.; Adam, I.; Adams, D. L. et al.
Object Type: Article
System: The UNT Digital Library
Environmental report 1998, executive summary (open access)

Environmental report 1998, executive summary

Lawrence Livermore National Laboratory (LLNL), a U.S. Department of Energy (DOE) facility operated by the University of California, serves as a national resource of scientific, technical, and engineering capabilities. The Laboratory's mission focuses on nuclear weapons and national security, and over the years has been broadened to include areas such as strategic defense, energy, the environment, biomedicine, technology transfer, the economy, and education. The Laboratory carries out this mission in compliance with local, state, and federal environmental regulatory requirements. It does so with the support of the Environmental Protection Department, which is responsible for environmental monitoring and analysis, hazardous waste management, environmental restoration, and assisting Laboratory organizations in ensuring compliance with environmental laws and regulations. LLNL comprises two sites: the Livermore site and Site 300. The Livermore site occupies an area of 3.28 square kilometers on the eastern edge of Livermore, California. Site 300, LLNL's experimental testing site, is located 24 kilometers to the east in the Altamont Hills, and occupies an area of 30.3 square kilometers. Environmental monitoring activities are conducted at both sites as well as in surrounding areas. This summary provides an overview of LLNL's environmental activities in 1998, including radiological and nonradiological surveillance, effluent, and compliance …
Date: September 22, 1999
Creator: Larson, J. M.; Harrach, R. J.; Althouse, P. E.; Bertoldo, N. A.; Biermann, A. H.; Blake, R. G. et al.
Object Type: Report
System: The UNT Digital Library
Precision Magnetic Elements for the SNS Storage Ring. (open access)

Precision Magnetic Elements for the SNS Storage Ring.

Magnetic elements for an accumulator storage ring for a 1 GeV Spallation Neutron Source (SNS) have been under design. The accumulation of very high intensity protons in a storage ring requires beam optical elements of very high purity to minimize higher order resonances in the presence of space charge. The parameters of the elements required by the accumulator lattice design have been reported. The dipoles have a 17cm gap and are 124cm long. The quadrupoles have a physical length to aperture diameter ratio of 40cm/21cm and of 45cm/31cm. Since the elements have a large aperture and short length, optimizing the optical effects of magnet ends is the major design challenge. Two dimensional (2D) computer computations can, at least on paper, produce the desired accuracy internal to magnets, i.e. constant dipole fields and linear quadrupole gradients over the desired aperture to 1 x 10{sup -4}. To minimize undesirable end effects three dimensional (3D) computations can be used to design magnet ends. However, limitations on computations can occur, such as necessary finite boundary conditions, actual properties of the iron employed, hysteresis effects, etc., which are slightly at variance with the assumed properties. Experimental refinement is employed to obtain the desired precision.
Date: March 29, 1999
Creator: Danby, G.; Jackson, J. & Spataro, C.
Object Type: Article
System: The UNT Digital Library