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The Automated Reasoning System ITP

Description: This report describes a system designed to provide a portable environment for the study of automated reasoning. The system is built on the LMA automated reasoning subroutine package. This program is not part of LMA itself but illustrates the level of inference-based system that can be constructed from the LMA package of tools. It is a clause-based reasoning system supporting a wide variety of techniques which have proven valuable over the years in a long-running automated deduction research project. In addition, it is designed to present a convenient, interactive interface to its user.
Date: April 1984
Creator: Lusk, Ewing L. & Overbeek, Ross A.

Automatic Transformations in the Inference Process

Description: A technique for incorporating automatic transformations into processes such as the application of inference rules, subsumption, and demodulation provides a mechanism for improving search strategies for theorem proving problems arising from the field of program verification. The incorporation of automatic transformations into the inference process can alter the search space for a given problem, and is particularly useful for problems having broad rather than deep proofs. The technique can also be used to permit the generation of inferences that might otherwise be blocked and to build some commutativity or associativity into the unification process. Appropriate choice of transformations, and new literal clashing and unification algorithms for applying them, showed significant improvement on several real problems according to several distinct criteria.
Date: July 1980
Creator: Veroff, Robert L.

Automotive Vehicle Sensors

Description: This report is an introduction to the field of automotive vehicle sensors. It contains a prototype data base for companies working in automotive vehicle sensors, as well as a prototype data base for automotive vehicle sensors. A market analysis is also included.
Date: September 1995
Creator: Sheen, S. H.; Raptis, A. C. & Moscynski, M. J.

Autoradiographic Technique for Rapid Inventory of Plutonium-Containing Fast Critical Assembly Fuel

Description: A nondestructive autoradiographic technique is described which can provide a verification of the piece count and the plutonium content of plutonium-containing fuel elements. This technique uses the spontaneously emitted gamma rays from plutonium to form images of fuel elements on photographic film. Autoradiography has the advantage of providing an inventory verification without the opening of containers or the handling of fuel elements. Missing fuel elements, substitution of nonradioactive material, and substitution of elements of different size are detectable. Results are presented for fuel elements in various storage configurations and for fuel elements contained in a fast critical assembly.
Date: October 1977
Creator: Brumbach, S. B. & Perry, R. B.

Autoradiography as a Safeguards Inspection Technique for Unirradiated LWR Fuel Assemblies

Description: A nondestructive autoradiographic method is described which can provide a verification that rods in the interior of unirradiated LWR fuel assemblies contain low-enriched uranium. Sufficient absorber must be used to reduce contributions to image density by beta radiation from uranium-238 daughters. When appropriate absorbers are used, the density of the image of a uranium-containing fuel rod is proportional to the uranium-235 enrichment in that rod. Exposure times as short as 1.5 hours can be achieved by using fast film and intensifying screens. Methods are discussed for reducing contributions to the image density of any single rod from radiation produced by all other rods in the assembly. The technique is useful for detecting missing rods, dummy rods, and rods containing depleted uranium. These defects can be detected by visual inspection of the autoradiographs. In its present state of development, the technique is not sensitive enough to reliably detect the difference between the various uranium-235 enrichments encountered in current BWR fuel assemblies. Results are presented for field tests of the technique at BWR and PWR facilities.
Date: May 1978
Creator: Brumbach, S. B. & Perry, R. B.

Avoiding Leakage Flow-Induced Vibration by a Tube-in-Tube Slip Joint

Description: Parameters and operating conditions (a stability map) were determined for which a specific slip-joint design did not cause self-excited lateral vibration of the two cantilevered, telescoping tubes forming the joint. The joint design featured a localized annular constriction. Flowrate, modal damping, tube engagement length, and eccentric positioning were among the parameters tested. Interestingly, all self-excited vibrations could be avoided by following a simple design rule: place constrictions only at the downstream end of the annular region between the tubes. Also, overall modal damping decreased with increased flowrate, at least initially, for upstream constrictions while the damping increased for downstream constrictions.
Date: October 1984
Creator: Mulcahy, T. M.

Baseline Energy Consumption Forecasts for Transportation: A Review and Evaluation

Description: A baseline projection of energy consumption is needed to estimate the potential energy savings from proposed transport technology and operational improvements. The Reference Energy System projection by Brookhaven National Laboratories and that which Stanford Research Institute produced for Gulf Oil are reviewed here. Attention is focused on the growth rate assumptions of the forecasts and the allowances made for the sensitivity of transport demand and technological efficiency to fuel price changes. The alternative trajectories of energy use are examined for automobile, bus and intercity air and rail passenger travel, and also for freight movement. Little, if any, justification can be found for many of the assumptions used to estimate transport demand and energy intensiveness. The assumptions underlying the Brookhaven National Laboratories projections are more explicit on changes in energy efficiency and energy price and shifts in transport patterns. However, the relationship of automobile travel, the largest component, to energy price is not specified clearly. The Stanford projection is based on seemingly arbitrary assumptions about changes in travel patterns and energy efficiency with no reference to the market process which must bring them about. It is concluded that the Brookhaven projection is a reasonable interim benchmark. Its structure should improve by refining and validating or revising the judgmental estimates on which it is based. This can be accomplished by identifying those judgments to which the energy consumption projections are most sensitive and modifying them, based on information presently available concerning the transport sector and/or information and relationships which can be developed by limited research.
Date: May 1976
Creator: Koppelman, Frank; O'Sullivan, Pat & Collum, Tom

Basic TRUEX Process for Rocky Flats Plant

Description: The Generic TRUEX Model was used to develop a TRUEX process flowsheet for recovering the transuranics (plutonium, americium) from a nitrate waste stream at Rocky Flats Plant. T\
Date: August 1994
Creator: Leonard, R. A.; Chamberlain, D. B.; Dow, J. A.; Farley, S. E.; Nuñez, Luis; Regalbuto, M. C. et al.

Benchmark Testing of the Finite-Strain Version of the LIFE-III Fast-Reactor-Element Code

Description: A collection of benchmark problems is used to test the finite-strain formulation of the LIFE-III fast-reactor fuel-element code. Analytical solutions for thick-wall cylinders loaded by internal and external pressure, valid for arbitrarily large strains, are presented for a linear viscous material. Similar problems are formulated for a nonlinear material, and numerical solutions are obtained using the Runge-Kutta method for the integration of an ordinary differential equation. These solutions are then compared with the corresponding solutions obtained using the LIFE-III code. With a proper choice of the number of spatial regions and time steps, good agreement is obtained between the two sets of solutions. The results indicate that the structural-analysis portion of the revised LIFE-III is valid for large strains.
Date: November 1976
Creator: Shack, W. J.; Jankus, V. Z. & Billone, Michael C.

Beyond "'Speedup": Performance Analysis of Parallel Programs

Description: This paper addresses the problem of measuring and analyzing the performance of fine-grained parallel programs running on shared-memory multiprocessors. Such processors use locking (either directly in the application program, or indirectly in a subroutine library or the operating system) to serialize accesses to global variables. Given sufficiently high rates of locking, the chief factor preventing linear speedup (besides lack of adequate inherent parallelism in the application) is lock contention - the blocking of processes that are trying to acquire a lock currently held by another process.
Date: February 1987
Creator: Dritz, Kenneth W. & Boyle, James M.

Biaxial Creep Behavior of Ribbed GCFR Cladding at 650 degrees C in Nominally Pure Helium (99. 99%)

Description: Biaxial creep-rupture tests were conducted on 12 prototypic GCFR fuel-cladding specimens at 650 deg C and a nominal hoop stress of 241.3 MPa. All test specimens were fabricated from 20% cold-worked Type 316 stainless steel tubes that were ribbed on the outer surface by mechanical grinding or electro-chemical etching. Test variables included specimen length and the presence or absence of weld-reinforcing end collars.
Date: November 1977
Creator: Yaggee, F. L.; Purohit, A.; Grajek, W. J. & Poeppel, R. B.

Biaxial Creep-Fatigue Behavior of Type 316H Stainless Steel Tube

Description: Biaxial creep-fatigue test data for Type 316 stainless steel tubes at 1100*Y are presented. The specimens were subjected to constant internal pressure and fluctuating axial strain with and without hold times in tension as well as compress ion. The results show that internal pressure significantly affects diametral ratchetting and axial stress range. Axial tensile hold is found to he more damaging than axial compressive hold even cinder a biaxial state of stress.
Date: April 1979
Creator: Majumdar, S.

Bibliography for Transportation Energy Conservation

Description: A listing is given of 578 reports, books, articles, and conference papers on transportation and energy. Coverage is primarily on U. S. developments and research from 1970 to 1975. Following a section of citations of general works on energy, the bibliography contains two main parts: ''Energy for Transportation'' and ''Transportation of Energy.'' Within each of these topics the arrangement is multimodal (at the urban, regional, national, or international level), then by mode. Selected information sources are listed in the last part. Within each section, entries are arranged alphabetically by author or, lacking an author, by title. References were drawn from the Transportation Center Library collection and other libraries in the Northwestern University system. An earlier bibliography, Transportation and Energy, compiled by the Transportation Center Library in March 1974, forms the basis for the arrangement and provides coverage from 1970 to 1973.
Date: May 1976
Creator: Northwestern University (Evanston, Ill.). Transportation Center. Library.

Bilinear Cyclic Stress-Strain Analysis for Incoloy 800

Description: This report describes the bilinear stress-strain analysis under cyclic loading conditions for the alloy Incoloy 800. Although the method for determining the bilinear stress-strain parameters is based on a procedure proposed in the RDT Standard F9-1 for inelastic analysis of Fast Flux Test Facility (FFTF) components, the accuracy and consistency of results have been improved by an analytical technique, which also resulted in certain simplifications. The bilinear stress-strain parameters of solution-annealed Incoloy 800 (Heat HH7058A) under cyclic loading conditions at a strain rate of 8.6 x 10⁻⁵ s⁻¹, total strain range of 0.2 to 0.8 percent, and temperatures of room temperature to 593 degrees C (1100 degrees F) have been determined. The dependence of bilinear parameters on temperature and strain is discussed. The cyclic-hardening characteristics based on correlation of yield parameter k with accumulated plastic strain are also presented.
Date: 1977?
Creator: Maiya, P. S.

Bilinear Cyclic Stress-Strain Parameters for Types 304 and 316 Stainless Steel

Description: The bilinear cyclic stress-strain parameters for Types 304 and 316 stainless steel are described. The bilinear properties of solution-annealed and aged Type 304 stainless steel (heat 9T2796) and solution-annealed Type 3l6 stainless steel (heat 8092297) under cyclic-loading conditions at a strain rate of 8.6 x 10⁵ s⁻¹, total strain range between 0.2 and 0.8 percent, and temperatures from 22 to 593 degrees C were determined. The dependence of bilinear parameters on maximum strain epsilon and temperature is discussed.
Date: July 1978
Creator: Maiya, P. S.

BlockSolve v1. 1: Scalable Library Software for the Parallel Solution of Sparse Linear Systems

Description: BlockSolve is a software library for solving large, sparse systems of linear equations on massively parallel computers. The matrices must be symmetric, but may have an arbitrary sparsity structure. BlockSolve is a portable package that is compatible with several different message-passing pardigms. This report gives detailed instructions on the use of BlockSolve in applications programs.
Date: March 1993
Creator: Jones, Mark T. & Plassmann, Paul E.

Boiling Heat Transfer of Refrigerant R-113 in a Small-Diameter, Horizontal Tube

Description: Results of a study of boiling heat transfer from refrigerant R-113 in a small-diameter (2.92-mm) tube are reported. Local heat transfer coefficients over a range of heat fluxes, mass fluxes, and equilibrium mass qualities were measured. The measured coefficients were used to evaluate eight different heat transfer correlations, some of which have been developed specifically for refrigerants. High heat fluxes and low flow rates are inherent in small channels, and this combination results in high boiling numbers. The high boiling number of the collected data shows that the nucleation mechanism was dominant. As a result, the two-phase correlations that predicted this dominance also predicted the data best if they also properly modeled the physical parameters. The correlations of Lazarek and Black and of Shah, as modified in this study, predicted the data very well. It is also shown that a simple form, suggested by Stephan and Abdelsalam for nucleate boiling, correlates the data equally well. This study is part of a research program in multiphase flow and heat transfer, with the overall objective of developing validated design correlations and predictive methods that will facilitate the design and optimization of compact heat exchangers for use with environmentally acceptable alternatives for chlorofluorocarbon (CFC) refrigerants and refrigerant mixtures.
Date: January 1992
Creator: Wambsganss, M. W.; France, D. M.; Jendrzejczyk, J. A. & Tran, T. N.

Boiling Heat Transfer with Three Fluids in Small Circular and Rectangular Channels

Description: Small circular and noncircular channels are representative of flow passages act evaporators and condensers. This report describes results of an experimental study on heat transfer to the flow boiling of refrigerants (R-12) and refrigerant-134a (R-134a) in a small horizontal circular-cross-section tube. The tube diameter of 2.46 mm was chosen to approximate the hydraulic diameter of a 4.06 x 1.70 mm rectangular channel previously studied with R-12, and a 2.92-mm-diameter circular tube previously studied with R-113. The objective of this study was to assess the effects of channel geometry and fluid properties on the heat transfer coefficient and to obtain additional insights relative to the heat transfer mechanism(s). The current circular flow channel for the R-12 and R-134a tests was made of brass and had an overall length of 0.9 in. The channel wall was electrically heated, and thermocouples were installed on the channel wall and in the bulk fluid stream. Voltage taps were located at the same axial locations as the stream thermocouples to allow testing over an exit quality range to 0.94 and a large range of mass flux (58 to 832 kg/m sq s) and heat flux (3.6 to 59 kW/m sq). Saturation pressure was nearly constant, averaging 0.82 MPa for most of the testing, with some tests performed at a lower pressure of 0.4--0.5 MPa. Local heat transfer coefficients were determined experimentally as a function of quality along the length of the test section. Analysis of all data for three tubes and three fluids supported the conclusion that a nucleation mechanism dominates for flow boiling in small channels. Nevertheless, a convection-dominant region was obtained experimentally in this study at very low values of wall superheat (<(approx) 2.75C). The circular and rectangular tube data for three fluids were successfully correlated in the nucleation-dominant region.
Date: January 1995
Creator: Tran, T. N.; Wambsganss, M. W. & France, D. M.