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An Algebraic Theory of Program Specification and Correctness Using Symmetry Operations

Description: This report applies some methods from the theory of group representation to the questions of program specification and knowledge about programs. The theory is that of a program as a transformation on a state space, and operators commuting with that transformation being symmetries of the program, means of specifying properties, and generators of program invariants. Because a program can simulate a system in the real world, there is a corresponding model of engineered artifacts, that is, manmade objects having a theory for their design.
Date: March 1987
Creator: Gabriel, John R.

An Alternative Library Under 4. 2 BSD UNIX on a VAX 11/780

Description: This paper describes an alternative library of elementary functions prepared for use with the standard Fortran compiler under 4.2 BSD UNIX on a VAX 11/780. The library, written in C and based on the book ''Software Manual for the Elementary Functions'' by Cody and Waite, offers improved accuracy over the standard system library, as well as additional capabilities. Listings and output from the ELEFUNT suite of test programs are included in the appendix.
Date: February 1986
Creator: Cody, William James

Alternatives for Conversion to Solid Interim Waste Forms of the Radioactive Liquid High-Level Wastes Stored at the Western New York Nuclear Service Center

Description: Techniques for isolating and solidifying the nuclear wastes in the storage tanks at the Western New York Nuclear Service Center plant have been examined. One technique involves evaporating the water and forming a molten salt containing the precipitated sludge. The salt is allowed to solidify and is stored in canisters until processing into a final waste form is to be done. Other techniques involve calcining the waste material, then agglomerating the calcine with sodium silicate to reduce its dispersibility. This option can also involve a prior separation and decontamination of the supernatant salt. The sludge and all resins containing fission-product activity are then calcined together. The technique of removing the water and solidifying the salt may be the simplest method for removing the waste from the West Valley Plant.
Date: August 1981
Creator: Vogler, S.; Trevorrow, L. E.; Ziegler, A. A. & Steindler, M. J.

Alternatives for Disposal of Raffinate from the TRUEX Process

Description: Possible methods for disposing of the immobilized raffinate from TRUEX processing are reviewed. The purpose of the TRUEX process is to extract transuranium elements from high-level and TRU wastes into a small volume that can be managed at lower cost than that of the original wastes. The raffinate from the TRUEX process, containing negligible concentrations of transuranium elements, would be combined with salt solutions also derived from processing high-level waste, and the mixture would be converted to grout.
Date: December 1989
Creator: Trevorrow, L. E. & Vandegrift, G. F.

Altitude and Generalized Configuration of the Top of the Floridian Aquifer, St. Johns County, Florida

Description: From introduction: This map shows the approximate altitude and configuration of the top of the Floridian aquifer...This map was prepared from geologic, geophysical, and drillers' logs on file with the Florida Bureau of Geology, U.S. Geological Survey, St. Johns River Water Management District, and from logs in published reports.
Date: 1984
Creator: Spechler, Rick M.

Analysis of an Internally Pressurized Prismatic Cell Can

Description: This report contains an elastic stress and displacement analysis of a prismatic cell can subjected to internal pressure. A computer program was written to perform the analysis. The results show that, for the geometry chosen, the thicknesses of the cell-can walls and the magnitude of the internal pressure are the most important parameters that determine the stresses and deformations of the cell can. Recommendations for future studies are included.
Date: April 1980
Creator: Majumdar, S.

Analysis of Cracked Core Spray Injection Line Piping from the Quad Cities Units 1 and 2 Boiling Water Reactors

Description: Elbow assemblies and adjacent piping from the loops A and B core spray injection lines of Quad Cities Units 1 and 2 Boiling Water Reactors have been examined in order to determine the nature and causes of coolant leakages and flaw indications detected during hydrostatic tests and subsequent ultrasonic inspections. The elbow assemblies were found to contain multiple intergranular cracks in the weld heat-affected zones. The cracking was predominantly axial in orientation in the forged elbow and wedge components, whereas mixed axial and circumferential cracking was seen in the wrought piping pieces. In at least two instances, axial cracks completely penetrated the circumferential weld joining adjacent components. Based upon the observations made in the present study, the failures were attributed to intergranular stress corrosion cracking caused by the weld-induced sensitized microstructure and residual stresses present; dissolved oxygen in the reactor coolant apparently served as the corrosive species. The predominantly axial orientation of the cracks present in the forged components is believed to be related to the banded microstructure present in these components. The metallographic studies reported are supplemented by x-radiography, chemical analysis and mechanical test results, determinations of the degree of sensitization present, and measurements of weld metal delta ferrite content.
Date: December 1983
Creator: Diercks, D. R.

Analysis of Heat-Pipe Absorbers in Evacuated-Tube Solar Collectors

Description: Heat transfer in evacuated-tube solar collectors with heat-pipe absorbers is compared with that for similar collectors with flow-through absorbers. In systems that produce hot water or other heated fluids, the heat-pipe absorber suffers a heat transfer penalty compared with the flow-through absorber, but in many cases the penalty can be minimized by proper design at the heat-pipe condenser and system manifold. The heat transfer penalty decreases with decreasing collector heat loss coefficient, suggesting that evacuated tubes with optical concentration are more appropriate for use with heat pipes than evacuated or non-evacuated flat-plate collectors. When the solar collector is used to drive an absorption chiller, the heat-pipe absorber has better heat transfer characteristics than the flow-through absorbers.
Date: February 1986
Creator: Hull, John R.; Schertz, William W. & Allen, John W.

Analysis of Proposed Gamma-Ray Detection System for the Monitoring of Core Water Inventory in a Pressurized Water Reactor

Description: An initial study has been performed of the feasibility of employing an axial array of gamma detectors located outside the pressure vessel to monitor the coolant in a PWR. A one-dimensional transport analysis model is developed for the LOFT research reactor and for a mock-PWR geometry. The gamma detector response to coolant voiding in the core and down-comer has been determined for both geometries. The effects of various conditions (for example, time after shutdown, materials in the transport path, and the relative void fraction in different water regions) on the detector response are studied. The calculational results have been validated by a favorable comparison with LOFT experimental data. Within the limitations and approximations considered in the analysis, the results indicate that the gamma-ray detection scheme is able to unambiguously respond to changes in the coolant inventory within any vessel water region.
Date: December 1987
Creator: Markoff, Diane Melanie

Analysis of Stream Quality in the Yampa River Basin, Colorado and Wyoming

Description: From introduction: This report relates to the first of the above objectives by describing stream quality in the Yampa River basin through 1976, with particular emphasis on conditions from August 1975 through September 1976. The content of this report is, at times, relatively technical. This is intentional. The report is aimed not at planners and decision makers but rather at those persons assigned the task of having to design, implement, and interpret a river basin assessment. The techniques and procedures used to determine ambient stream quality in the Yampa River basin have been presented in detail so that their applicability to other river basins can be determined. For the planner and decision maker, the results presented in this report are summarized in less technical terms in phase-l (Steele and others, 1979) and phase-ll summary reports.
Date: April 1980
Creator: Wentz, Dennis A. & Steele, Timothy Doak

Analysis of the Mount Laguna Photovoltaic Cell Failure

Description: From summary: The purpose of this analysis is to provide photovoltaic (P/V) system design and field engineers with an understanding of the primary factors which can cause individual P/V cells in a module or an array to be forced into reverse bias and eventual failure and to provide guidelines for the adequate protection of the cells.
Date: January 1981
Creator: Anderson, E.

Analysis of the October 5, 1979 Lithium Spill and Fire in the Lithium Processing Test Loop

Description: On October 5, 1979, the Lithium Processing Test Loop (LPTL) developed a lithium leak in the electromagnetic (EM) pump channel, which damaged the pump, its surrounding support structure, and the underlying floor pan. A thorough analysis of the causes and consequences of the pump failure was conducted by personnel from CEN and several other ANL divisions. Metallurgical analyses of the elliptical pump channel and adjacent piping revealed that there was a significant buildup of iron-rich crystallites and other solid material in the region of the current-carrying bus bars (region of high magnetic field), which may have resulted in a flow restriction that contributed to the deterioration of the channel walls. The location of the failure was in a region of high residual stress (due to cold work produced during channel fabrication); this failure is typical of other cold work/stress-related failures encountered in components operated in forced-circulation lithium loops. Another important result was the isolation of crystals of a compound characterized as Li/sub x/CrN/sub y/. Compounds of this type are believed to be responsible for much of the Fe, Cr, and Ni mass transfer encountered in lithium loops constructed of stainless steel. The importance of nitrogen in the mass-transfer mechanism has long been suspected, but the existence of stable ternary Li-M-N compounds (M = Fe, Cr, Ni) had not previously been verified.
Date: December 1981
Creator: Maroni, V. A.