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Statistical Identification of Effective Input Variables: This report provides background and procedural information for the use of a general-purpose Stirling-engine analysis code developed at Argonne National Laboratory and available through the National Energy Software Center. Different engine configurations are easily specified, or the user may make use of provided data for existing engines, both kinematic and free piston. The code models heat transfer and fluid mechanics throughout the engine and accounts for system energy flows and losses. Good agreement is shown between code predictions and experimental measurements. The present analysis method was chosen for fast execution and useful information on energy flows in the system. A description is provided of the code structure that is intended to accept different analysis modules that can provide improved system modeling or optimization capability.
Proceedings of the 1982 Symposium on Instrumentation and Control for Fossil Energy Processes : June 7-9, 1982 Adam's Mark Hotel, Houston, Texas: This sixth symposium covers process control processes and issues involved in the conversion of fossil fuels into synthetic fuels.
Stability of Tube Rows in Crossflow: A mathematical model for the instability of tube rows subjected to crossflow is examined. The theoretical model, based on the fluid-force data for a pitch-to-diameter ratio of 1.33, provides additional insight into the instability phenomenon. Tests are also conducted for three sets of tube rows. The effects of mass ratio, tube pitch, damping, detuning and finned tubes are investigated. Theoretical results and experimental data are in good agreement.
Fuel-Motion Diagnostics and Cineradiography: Nuclear and non-nuclear applications of cineradiography are reviewed, with emphasis on diagnostic instrumentation for in-pile transient-reactor safety testing of nuclear fuel motion. The primary instrument for this purpose has been the fast-neutron hodoscope, which has achieved quantitative monitoring of time, location, mass, and velocity of fuel movement under the difficult conditions associated with transient-reactor experiments. Alternative diagnostic devices that have been developed have not matched the capabilities of the hodoscope. Other applications for the fuel-motion diagnostic apparatus are also evolving, including time-integrated radiography and direct time- and space-resolved fuel-pin power monitoring. Although only two reactors are now actively equipped with high-resolution fuel-motion diagnostic systems, studies and tests have been carried out in and for many other reactors.
Randomly Generated Test Problems for Positive Definite Quadratic Programming: A procedure is described for randomly generating positive definite quadratic programming test problems. The test problems are constructed in the form of linear least squares problems subject to linear constraints. The probability measure for the problems so generated is invariant under orthogonal transformations. The procedure allows the user to specify the size of the least squares problem (number of unknown parameters, number of observations, and number of constraints); the relative magnitude of the residuals; the condition number of the Hessian matrix of the objective function; and the structure of the feasible region (number of equality constraints and the number of inequalities which will be active at the feasible starting point and at the optimal solution). An example is given illustrating how these problems can be used to evaluate the performance of a software package.
An LMA-Based Theorem Prover: We describe here a theorem prover constructed from the facilities provided by Logic Machine Architecture (LMA). This program is not part of LMA itself, but illustrates the level of inference-based system which can be constructed from the LMA package of tools. It is a clause-based theorem prover 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 which includes a number of useful utility commands.
DYNAPCON: A Computer Code for Dynamic Analysis of Prestressed Concrete Structures: A finite element computer code for the transient analysis of prestressed concrete reactor vessels (PCRVs) for LMFBR containment is described. The method assumes rotational symmetry of the structure. Time integration is by an explicit method. The quasistatic prestressing operation of the PCRV model is performed by a dynamic relaxation technique. The material model accounts for the crushing and tensile cracking in arbitrary direction in concrete and the elastic-plastic behavior of reinforcing steel. The variation of the concrete tensile cracking and compressive crushing limits with strain rate is taken into account. Relative slip is permitted between the concrete and tendons. Several example solutions are presented and compared with experimental results. These sample problems range from simply supported beams to small scale models of PCRV's. It is shown that the analytical methods correlate quite well with experimental results, although in the vicinity of the failure load the response of the models tend to be quite sensitive to input parameters.
Chemical Engineering Division Annual Technical Report 1981: Highlights of the Chemical Engineering (CEN) Division's activities during 1981 are presented. In this period, CEN conducted research and development in the following areas: rechargeable lithium-alloy/iron sulfide batteries for electric vehicles and other applications, aqueous batteries--improved lead-acid, nickel/zinc, and nickel/iron--for electric vehicles, as well as advanced lead-acid batteries for electric.-utility load leveling, energy-efficient industrial electrochemical processes, molten carbonate fuel cells for use by electric utilities, coal technology, mainly fluidized-bed combustion of coal in the presence of an SO2 sorbent of limestone, heat- and seed-recovery technology for open-cycle magnetohydrodynamic systems.
Radiological and Environmental Research Division Annual Report: Part 1, Fundamental Molecular Physics, October 1980-September 1981: Annual report of the Argonne National Laboratory Radiological and Environmental Research Division regarding activities related to molecular physics and chemistry. This report discusses areas in the physics and chemistry of atoms and molecules related to their interactions with photons, electrons, and other external agents such as energetic ions.
Radiological and Environmental Research Division Annual Report: Part 2, Center for Human Radiobiology, July 1980-June 1981: Annual report of the Argonne National Laboratory Radiological and Environmental Research Division regarding activities related to the Center for Human Radiobiology. This report contains a mixture of original countributions, abstracts of published papers, and summaries of papers presented at meetings.
Radiological and Environmental Research Division Annual Report: Part 3, Ecology, January-December 1981: Annual report of the Argonne National Laboratory Radiological and Environmental Research Division regarding activities related to ecology and funding issues during the year.
Radiological and Environmental Research Division Annual Report: Part 4, Atmospheric Physics, January-December 1981: Annual report of the Argonne National Laboratory Radiological and Environmental Research Division regarding activities related to atmospheric physics. This report discusses the section's participation in the Atmospheric Studies in COmplex Terrain (ASCOT) experiment.
Radiological and Environmental Research Division Annual Report: Part 2, Center for Human Radiobiology, July 1981-June 1982: Annual report of the Argonne National Laboratory Radiological and Environmental Research Division regarding activities related to the Center for Human Radiobiology. This report discusses studies on the health effects of radium.
Fuel Cycle Programs, Quarterly Progress Report: January-March 1981: Quarterly report of the Argonne National Laboratory Chemical Engineering Division regarding activities related to properties and handling of radioactive materials, operation of nuclear reactors, and other relevant research.
Fuel Cycle Programs, Quarterly Progress Report: April-June 1981: Quarterly report of the Argonne National Laboratory Chemical Engineering Division regarding activities related to properties and handling of radioactive materials, operation of nuclear reactors, and other relevant research.
Fuel Cycle Programs, Quarterly Progress Report: July-September 1981: Quarterly report of the Argonne National Laboratory Chemical Engineering Division regarding activities related to properties and handling of radioactive materials, operation of nuclear reactors, and other relevant research.
Fuel Cycle Programs, Quarterly Progress Report: October-December 1981: Quarterly report of the Argonne National Laboratory Chemical Engineering Division regarding activities related to properties and handling of radioactive materials, operation of nuclear reactors, and other relevant research.
Fuel Cycle Programs, Quarterly Progress Report: January-March 1982: Quarterly report of the Argonne National Laboratory Chemical Engineering Division regarding activities related to properties and handling of radioactive materials, operation of nuclear reactors, and other relevant research.
Advanced Fuel Cell Development Progress Report: October-December 1980: Quarterly report discussing fuel cell research and development work at Argonne National Laboratory (ANL). This report describes efforts directed toward (1) developing alternative concepts for components of molten carbonate fuel cells and (2) improving understanding of component behavior.
Advanced Fuel Cell Development Progress Report: April-June 1981: Quarterly report discussing fuel cell research and development work at Argonne National Laboratory (ANL). This report describes efforts directed toward (1) improving understanding of component behavior in molten carbonate fuel cells and (2) developing alternative concepts for components. The principal focus has been on the development of sintered y-LiAIO2 electrolyte supports, stable NiO cathodes, and hydrogen diffusion barriers. Cell tests were performed to assess diffusion barriers and to study cathode voltage relaxation following current interruption.
Advanced Fuel Cell Development Progress Report: July-September 1981: Quarterly report discussing fuel cell research and development work at Argonne National Laboratory (ANL). This report describes efforts directed toward (1) improving understanding of component behavior in molten carbonate fuel cells and (2) developing alternative concepts for components.
Physics Division Annual Review, 1 April 1980-31 March 1981: The Physics Division's program in nuclear physics covers a broad span of activities within that discipline. The object of this research is to understand the properties of atomic nuclei, their structure, the mechanisms of nuclear reactions, and manifestations of fundamental symmetries in nuclei. Work is carried out under a variety of subprograms: theory, heavy-ion physics, medium-energy physics and nuclear research. These categories do not represent a sharp separation between people--individual scientists often work in several different areas. This flexibility allows scientific problems to be addressed with a variety of techniques, and it avoids limiting individual scientists' activities to a particular subdiscipline.
Physics Division Annual Review: 1 April 1981-31 March 1982: The research program in nuclear physics in the Argonne Physics Division contributes to most of the major questions in this scientific discipline. The development of the superconducting rf linac technology has led to the ATLAS project now under construction, and is the major focus of the effort in heavy-ion research. The investigation of pion interactions in nuclei using the LAMPF facility helps delineate the dominant aspects of pion propagation and interactions in nuclei. Experiments on the weak interaction in nuclei and on other fundamental symmetries are being carried out with a number of tools. The theoretical effort in nuclear structure, nuclear matter and dynamics, and reaction theory is closely coupled to many aspects of the experimental programs.
Proceedings of the NEANDC/NEACRP Specialists Meeting on Fast-Neutron Capture Cross Sections: This proceedings contains the summaries and contents of a number of papers presented at the 1982 NEANDC/NEACRP specialists meeting on fast-neutron capture cross sections. The table of contents has been summarized to provide a sketch of the topical matter.
Fuels for Research and Test Reactors, Status Review: July 1982: A thorough review is provided on nuclear fuels for steady-state thermal research and test reactors. The review was conducted to provide a documented data base in support of recent advances in research and test reactor fuel development, manufacture, and demonstration in response to current US policy on availability of enriched uranium. The review covers current fabrication practice, fabrication development efforts, irradiation performance, and properties affecting fuel utilization, including thermal conductivity, specific heat, density, thermal expansion, corrosion, phase stability, mechanical properties, and fission-product release. The emphasis is on US activities, but major work in Europe and elsewhere is included. The standard fuel types discussed are the U-Al alloy, UZrH/sub x/, and UO2 rod fuels. Among new fuels, those given major emphasis include H3Si-Al dispersion and UO2 caramel plate fuels.
Fluidelastic Instability in Shell and Tube Heat Exchangers: A Framework for a Prediction Method: A framework for a method to predict fluid-elastic instability in heat exchanger tube bundles is presented. The method relies on a three-dimensional, cylindrical coordinate, thermal-hydraulic analysis code to obtain a representation of the three-dimensional flow distribution within the heat exchanger. With this information, local cross-flow velocities corresponding to each tube in the exchanger are obtained by interpolation and resultant cross-flow velocity distributions are computed. With a knowledge of the vibration mode shapes and frequencies, reduced effective cross-flow velocities are then computed for each tube. A comparison with experimental results shows excellent agreement: the tubes with high values of predicted reduced effective cross-flow velocity are the same tubes that first experience fluid-elastic instability in the flow tests and vibrate most violently; also, the simulation correctly predicts that the tubes directly exposed to the flow from the inlet nozzle have a low potential for fluid-elastic instability. Very good agreement is also shown in the comparison of the predicted reduced effective cross-flow velocities with the critical value obtained from a design guide. In summary, the feasibility of developing a heat exchanger tube vibration prediction method, based on a computer simulation of flow distribution, is demonstrated. Such a method would have immediate application in design optimization. However, further development and evaluation are required.
An Evaluation of Structural Integrity of IPNS-I and ZING-P' Targets: This report discusses the design, production, and evaluation of clad uranium-alloy targets that function as spallation neutron sources in the ZING-P' and IPNS-I facilities with a pulsed (10 to 30 Hz), 500-MeV proton beam. The methodology and results of theoretical nuclear-particle transport, heat transport, and stress analyses that were used in the development of a design for the targets are described. The production of a zirconium-clad uranium-alloy cylinder for ZING-P' and Zircaloy-2-clad uranium-alloy discs for IPNS-I is discussed with particular attention to the procedural details. The theoretical analyses were verified by measuring the thermal and mechanical response of the clad uranium under conditions designed to simulate the operations of the pulsed-neutron sources.
Proceedings of the 1981 Symposium on Instrumentation and Control for Fossil-Energy Processes: June 8-10, 1981 Sheraton-Palace Hotel, San Francisco, California: Compiled proceedings of the fifth Symposium on Instrumentation and Control for Fossil-Energy Processes, covering process control involved in the conversion of fossil fuels into synthetic fuels.
Separation of Rubidium from Irradiated Aluminum-Encapsulated Uranium: A procedure was developed for separating rubidium from irradiated aluminum encapsulated uranium. The separations procedure produces a final ultra-high purity rubidium chloride product for subsequent high performance mass spectrometric analysis. The procedure involves first removing most of the macro-components and fission products by strong base anion exchange using, first, concentrated HCl, then oxalic acid media and second, selectively separating rubidium from alkaline-earth ions and other alkali-metal ions, including cesium, using Bio-Rex-40 cation-exchange resin. The resultant rubidium chloride is then put through a final vacuum sublimation step. Ultra-pure reagents and specially clean glassware are used throughout the procedure to minimize contamination by naturally-occurring rubidium.
Improving the Accuracy of Computed Singular Values: This paper describes a computational method for improving the accuracy of a given singular value and its associated left and right singular vectors. The method is analogous to iterative improvement for the solution of linear systems. That is, by means of a low-precision computation, an iterative algorithm is applied to increase the accuracy of the singular value and vectors; extended precision computations are used in the residual calculation. The method is related to Newton's Method applied to the singular value problem and inverse iteration for the eigenvalue problem.
Natural Thermal Stratification in Tanks : Phase 1 Final Report: This report describes how solar system tanks fail to stratify, a new solar system control strategy that allows stratification, a one-dimensional analytical model of thermally stratified tanks, experimental measurement of thermal stratification in tanks, correlation of experimental measurements with empirical constants in the analytical model, and a procedure for designing thermally stratified tanks. Failure to stratify is explained in terms of the critical Richardson number. The key to the new control strategy is to avoid a Richardson number that decreases during solar collection. The analytical model is an approximate solution based on assumptions that (1) the solution is a function of elevation and time, only, (2) plug flow exists, (3) flow rate is constant, (4) the cross-sectional areas of the tank and tank wall are constant, (5) there is a step change of inlet temperature, (6) there is heat transfer between the tank wall and the water, and (7) thermal losses from the tank are negligible. Empirical constants in the theory are determined by adjusting them until the best least-squares fit with experimental data is obtained and correlating the constants with the Fourier and Richardson numbers. The new control strategy allows tanks to stratify and reduces the average collector operating temperature by as much as 20/sup 0/C. The result is up to 20% improvement in system performance. The analytical model and correlation of its empirical constants allow system designers to select from several alternatives the tank configuration that provides the best stratification.
The Application of Neutron-Activation Analysis to the Determination of Leach Rates of Simulated Nuclear-Waste Forms: The application of neutron activation analysis to the determination of element release from simulated nuclear waste forms during leaching is described for several different glasses. Potential neutron irradiation effects are discussed, and it is shown, by a series of leach tests on activated and non-activated glass samples, that neutron irradiation has no discernible effect on the release of silicon and cesium during leaching. The radioisotopes best suited for analysis with this method and their associated detection limits are identified, and the method's applicability to waste forms other than glass is discussed.
Effects of Ionization on Silicate Glasses: This evaluation of radiation effects in silicate glasses caused by ionization is based on our own investigations, on material collected in our files (reports, articles, and notes), and on a computer literature search through recent issues of Physics Abstracts and Chemical Abstracts (and the apparently pertinent references which appeared). Some of the recent results, available heretofore only in internal correspondence, are presented in some detail. It is concluded that research into the behavior of silicate glasses generally will be required before the specific effects in the radioactive waste storage glasses can be properly understood and evaluated. Two particular neglected areas of investigation are targeted for immediate concern: a kinetic analysis of annealing data and the acquisition of data on effects of irradiation at controlled elevated temperatures.
Newton's Method: Newton's method plays a central role in the development of numerical techniques for optimization. In fact, most of the current practical methods for optimization can be viewed as variations on Newton's method. It is therefore important to understand Newton's method as an algorithm in its own right and as a key introduction to the most recent ideas in this area. One of the aims of this expository paper is to present and analyze two main approaches to Newton's method for unconstrained minimization: the line search approach and the trust region approach. The other aim is to present some of the recent developments in the optimization field which are related to Newton's method. In particular, we explore several variations on Newton's method which are appropriate for large scale problems, and we also show how quasi-Newton methods can be derived quite naturally from Newton's method.
The Measurement of Leaching from Simulated Nuclear-Waste Glass Using Radiotracers: The use of radiotracer spiking as a method of measuring the leaching from simulated nuclear-waste glass is shown to give results comparable with other analytical detection methods. The leaching behavior of strontium-85, ruthenium-106, barium-133, cesium-137, cerium-141, europium-152, and other isotopes is measured for several defense waste glasses. These tests show that radiotracer spiking is a sensitive, multi-element technique that can provide leaching data, for actual waste elements, that are difficult to obtain by other methods. Additionally, a detailed procedure is described that allows spiked glass to be prepared with a suitable distribution of radionuclides.
The Hydration Process of Nuclear-Waste Glass: An Interim Report: Aging of simulated nuclear waste glass by contact with a controlled-temperature, humid atmosphere results in the formation of a double hydration layer penetrating the glass, as well as the formation of minerals on the glass surface. The hydration process can be described by Arrhenius behavior between 120 and 240 C. Results suggest that simulated aging reactions are necessary for demonstrating that nuclear waste forms can meet projected Nuclear Regulatory Commission regulations.
Control Rods in LMFBRs: A Physics Assessment: This physics assessment is based on roughly 300 control rod worth measurements in ZPPR from 1972 to 1981. All ZPPR assemblies simulated mixed-oxide LMFBRs, representing sizes of 350, 700, and 900 MWe. Control rod worth measurements included single rods, various combinations of rods, and tantalum and europium rods. Additional measurements studied variations in B4C enrichment, rod interaction effects, variations in rod geometry, neutron streaming in sodium-filled channels, and axial worth profiles. Analyses were done with design-equivalent methods, using ENDF/B Version IV data. Some computations for the sensitivities to approximations in the methods have been included. Comparisons of these analyses with the experiments have allowed the status of control rod physics in the US to be clearly defined.
A Study of the Uranium-Aluminum-Silicon System: The U-Al-Si system was investigated in the composition range from U to U-80 at.% Al to U-75 at.% Si. More than 260 binary and ternary alloys were arc melted and studied by metallographic and x-ray powder diffraction techniques, in the as-cast condition and after thermal treatment at temperatures ranging from 700 to 1040 C. One or possibly two ternary compounds of undetermined crystal structure exist at or near U2AlSi2 The binary silicides U3Si, U3Si2, and USi can dissolve only small amounts of Al in solid solution, but the higher silicides U3Si5, USi2-x, and USi/sub 3/ dissolve increasingly larger amounts of Al. Of the three binary aluminides, UAl2 can dissolve more than 12 at.% Si in solid solution. UAl3 forms a continuous solid solution with USi3, and UAl4 is not present in alloys containing more than 3 at.% Si.
GeV C. W. Electron Microtron Design Report: Rising interest in the nuclear physics community in a GeV C.W. electron accelerator reflects the growing importance of high-resolution short-range nuclear physics to future advances in the field. In this report major current problems are reviewed and the details of prospective measurements which could be made with a GeV C.W. electron facility are discussed, together with their impact on an understanding of nuclear forces and the structure of nuclear matter. The microtron accelerator has been chosen as the technology to generate the electron beams required for the research discussed because of the advantages of superior beam quality, low capital and operating cost and capability of furnishing beams of several energies and intensities simultaneously. A complete technical description of the conceptual design for a 2 GeV double-sided C.W. electron microtron is presented. The accelerator can furnish three beams with independently controlled energy and intensity. The maximum current per beam is 100 mircoamps. Although the precise objective for maximum beam energy is still a subject of debate, the design developed in this study provides the base technology for microtron accelerators at higher energies (2 to 6 GeV) using multi-sided geometries.
A Computer-Based Accountability System (Phase I) for Special Nuclear Materials at Argonne-West: An automated accountability system for special nuclear materials (SNM) is under development at Argonne National Laboratory-West. Phase I of the development effort has established the following basic features of the system: a unique file organization allows rapid updating or retrieval of the status of various SNM, based on "batch numbers," storage location, serial number, or other attributes. Access to the program is controlled by an interactive user interface that can be easily understood by operators who have had no prior background in electronic data processing. Extensive use of structured programming techniques make the software package easy to understand and to modify for specific applications. All routines are written in FORTRAN.
Six Language Extensions to Enhance the Portability of Mathematical Software Written in PL/I: Background and Justification: This report proposes six extensions to ANS PL/I, which is being revised by the American National Standards Committee X3J1. The new features include environmental enquiry functions, generalization of restricted expressions (compile-time expressions), liberalization of the contexts of restricted expressions, a named-literal declaration type, explicit precision specification for constants, and a pragmatic statement for expressing conditions that an implementation must satisfy for acceptable compilation. Used together, these features will give numerical analysts access to properties of an implementation's floating-point arithmetic in exactly the ways required to ease the burden of tailoring a program's precision specifications to new environments. In many cases it will be possible to write PL/I programs that are completely self-adapting to their host environment. Effective definition of the environmental enquiry functions will require the incorporation of an explicitly parameterized model of floating-point arithmetic. If such a model is integrated into the Standard, numerical analysts will be able to state and prove theorems about their programs' error bounds by appealing directly to the Standard.
LINPACK Working Note #15 : LINPACK, a Package for Solving Linear Systems: The design, development, and use of the software package called LINPACK, a collection of subroutines to solve various systems of simultaneous linear algebraic equations are described. The package has been designed to be machine-independent and fully portable and to run efficiently in many operating environments.
The Effect of Pressure on the Transient Swelling Rate of Oxide Fuel: An analysis of the transient swelling rate of oxide fuel, based on fission-gas bubble conditions calculated with the FRAS3 code, has been developed and implemented in the code. The need for this capability arises in the coupling of the FRAS3 fission-gas analysis code to the FPIN fuel-pin mechanics code. An efficient means of closely coupling the calculations of swelling strains and stresses between the modules is required. The present analysis provides parameters that allow the FPIN calculation to proceed through a fairly large time step, using estimated swelling rates, to calculate the stresses. These stress values can then be applied in the FRAS3 detailed calculation to refine the swelling calculation, and to provide new values for the parameters to estimate the swelling in the next time step. The swelling rates were calculated for two representative transients and used to estimate swelling over a short time period for various stress levels.
Software for Estimating Sparse Jacobian Matrices: In many nonlinear problems it is necessary to estimate the Jacobian matrix of a nonlinear mapping F. In large scale problems the Jacobian of F is usually sparse, and then estimation by differences is attractive because the number of differences can be small compared to the dimension of the problem. For example, if the Jacobian matrix is banded then the number of differences needed to estimate the Jacobian matrix is, at most, the width of the band. In this paper we describe a set of subroutines whose purpose is to estimate the Jacobian matrix of a mapping F with the least possible number of function evaluations.
Final Report of Experimental Laboratory-Scale Brittle Fracture Studies of Glasses and Ceramics: This report discuses results of an experimental program to characterize the fragments generated when brittle glasses and cermaics are impacted.
Light-Water-Reactor Fission-Product Data Assessment: This assessment seeks (1) to determine the most probable chemical compounds formed between fission products and actinides in urania fuels under normal and accident conditions and (2) to identify gaps in knowledge of these fission-product compounds. The ultimate goal of this effort is to develop predictive capability about the behavior of fission products under normal and accident conditions. The relevant thermochemical data have been organized by compound type, the chemical stability of resultant compounds determined, and data uncertainty evaluated. The assessment focused on fission-product and actinide oxides, halides, tellurides, and hydroxides. Free energy equations are given for those compounds for which data were available.
A Methodology for Algorithm Development Through Schema Transformations: A programming methodology based on schema transformations is presented. Such an approach is a logical outcome of recent developments in program manipulating systems. Concurrent development of algorithms and their proofs of correctness is a significant feature of the proposed methodology. As the development process begins with an abstract schema, it is often possible to derive several related end algorithms in a single development process. This has implications in both the economics of software development and the understanding and teaching of algorithms. The initial schematic specification (a skeleton algorithm schema), the intermediate and final algorithm schemata are all expressed in Darlington's first-order recursion equation language exploiting set-theoretic constructs. A set of transformation rules together with a set of reduction rules for set expressions is then used to successively transform the schematic specification into different algorithm schemata. Most of the transformations are applications of a small number of common rewriting rules.
A Coupled Heat Conduction and Thermal Stress Formulation Using Explicit Integration: The formulation needed for the conductance of heat by means of explicit integration is presented. The implementation of these expressions into a transient structural code, which is also based on explicit temporal integration, is described. Comparisons of theoretical results with code predictions are given both for one-dimensional and two-dimensional problems. The coupled thermal and structural solution of a concrete crucible, when subjected to a sudden temperature increase, shows the history of cracking. The extent of cracking is compared with experimental data.
JAKEF: A Portable Symbolic Differentiator of Functions Given by Algorithms: JAKEF is a compiler that accepts as data a single or double precision FORTRAN subroutine program defining an objective function F(x) or a vector function f(x) and produces as output a single or double precision FORTRAN program defining the gradient of F(x) or the Jacobian of f(x).
NDA Safeguards Techniques for LMFBR Assemblies: Report discussing safeguards for liquid-metal fast breeder reactors (LMFBFRs) and their fuel handling systems.

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