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Final report on characterizing the dynamics of spatio-temporal data

Description: One principal goal of the grant was to model and analyze the dynamics of spatially extended chaotic systems. One of the principal tools used in the analysis was KLTOOL, a computer package developed by the principal investigators for Karhunen-Loeve analysis. The package was used to analyze video data from a laboratory experiment on cellular flames. A second goal of the project was to analyze complex time series whose underlying dynamics may be low dimensionally chaotic. Particular emphasis was placed on systems of possible relevance to energy production and distribution. The work attempted to characterize low-dimensional aspects of the dynamics of a fluidized bed, in particular, a transition from periodic to irregular behavior. Finally, collaborators worked on aspects of targeting in chaotic dynamical systems. This work showed that it is possible to switch a moderately high-dimensional chaotic process rapidly between prespecified periodic saddle orbits embedding within the attractor. Additional work extended previously-developed algorithms for the highly accurate computation of stable manifolds of periodic saddle orbits, which is essential to the successful application of targeting algorithms.
Date: September 1, 1998
Creator: Kostelich, E.J. & Armbruster, H.D.
Partner: UNT Libraries Government Documents Department

Algorithm for computing significance levels using the Kolmogorov-Smirnov statistic and valid for both large and small samples

Description: The KSTEST code presented here is designed to perform the Kolmogorov-Smirnov one-sample test. The code may be used as a stand-alone program or the principal subroutines may be excerpted and used to service other programs. The Kolmogorov-Smirnov one-sample test is a nonparametric goodness-of-fit test. A number of codes to perform this test are in existence, but they suffer from the inability to provide meaningful results in the case of small sample sizes (number of values less than or equal to 80). The KSTEST code overcomes this inadequacy by using two distinct algorithms. If the sample size is greater than 80, an asymptotic series developed by Smirnov is evaluated. If the sample size is 80 or less, a table of values generated by Birnbaum is referenced. Valid results can be obtained from KSTEST when the sample contains from 3 to 300 data points. The program was developed on a Digital Equipment Corporation PDP-10 computer using the FORTRAN-10 language. The code size is approximately 450 card images and the typical CPU execution time is 0.19 s.
Date: October 1, 1983
Creator: Kurtz, S.E. & Fields, D.E.
Partner: UNT Libraries Government Documents Department

PVODE and KINSOL: parallel software for differential and nonlinear systems

Description: In this project, parallel general-purpose software for two classes of mathematical problems has been developed. PVODE is a portable solver for ordinary differential equation systems, based on robustmathematical algorithms, and targeted at large systems on parallel machines. It is the parallel extension of the earlier sequential solver CVODE. A related solver called KINSOL has been developed for systems of nonlinear algebraic equations. KINSOL was first developed as a sequential solver, on a design that permitted extending it to a parallel version with fairly minimal additions. Both PVODE and KINSOL are being used within a parallel version of the tokamak edge plasma model UEDGE. KINSOL is also being applied in the ParFlow groundwater flow model to solve a nonlinear pressure equation.
Date: February 1, 1998
Creator: Hindmarsh, A.C. & Taylor, A.G.
Partner: UNT Libraries Government Documents Department

KENO lifetimes

Description: When performing k-eigenvalue solutions with KENO-V.a, two different prompt neutron lifetimes are estimated - a system lifetime and a neutron generation time. The meaning of these two lifetimes has been ascertained by comparing values of various neutron lifespans/lifetimes predicted by MCNP and DANTSYS based on the neutron-balance theory. The system lifetime in KENO-Va corresponds to the unweighted removal lifetime calculated by both MCNP and DANTSYS. The unweighted removal lifetime is the average time between removal events resulting from a neutron absorption or a neutron leakage. The generation time in KENO-V.a corresponds to the fission lifespan calculated by MCNP, where the fission lifespan in MCNP represents the average time for a newly born neutron to cause another fission. As such, the generation time in KENO-Va does not represent the generation time that appears in the point kinetic model. The generation time in the point kinetic model is the adjoint-weighted removal lifetime divided by k{sub eff}, which is identically equal to the adjoint-weighted neutron production rate. In small bare systems operating in the vicinity of delayed critical, the difference between the adjoint-weighted neutron generation time and the fission lifespan can be as small as a few percent. However, in reflected systems, the difference between these two quantities can be several orders of magnitude. In conclusion, the prompt neutron generation time predicted by KENO-Va corresponds to the fission lifespan of a prompt neutron in a given system. The fission lifespan is the average time from birth-to-fission and, in general, is not a good approximation for the adjoint-weighted neutron generation time that appears in the point-kinetic model.
Date: January 30, 1997
Creator: Petrie, L.; Parsons, D.K. & Spriggs, G.D.
Partner: UNT Libraries Government Documents Department

User documentation for KINSOL, a nonlinear solver for sequential and parallel computers

Description: KINSOL is a general purpose nonlinear system solver callable from either C or Fortran programs It is based on NKSOL [3], but is written in ANSI-standard C rather than Fortran77 Its most notable feature is that it uses Krylov Inexact Newton techniques in the system`s approximate solution, thus sharing significant modules previously written within CASC at LLNL to support CVODE[6, 7]/PVODE[9, 5] It also requires almost no matrix storage for solving the Newton equations as compared to direct methods The name KINSOL is derived from those techniques Krylov Inexact Newton SOLver The package was arranged so that selecting one of two forms of a single module in the compilation process will allow the entire package to be created in either sequential (serial) or parallel form The parallel version of KINSOL uses MPI (Message-Passing Interface) [8] and an appropriately revised version of the vector module NVECTOR, as mentioned above, to achieve parallelism and portability KINSOL in parallel form is intended for the SPMD (Single Program Multiple Data) model with distributed memory, in which all vectors are identically distributed across processors In particular, the vector module NVECTOR is designed to help the user assign a contiguous segment of a given vector to each of the processors for parallel computation Several primitives were added to NVECTOR as originally written for PVODE to implement KINSOL KINSOL has been run on a Cray-T3D, an eight- processor DEC ALPHA and a cluster of workstations It is currently being used in a simulation of tokamak edge plasmas and in groundwater two-phase flow studies at LLNL The remainder of this paper is organized as follows Section 2 sets the mathematical notation and summarizes the basic methods Section 3 summarizes the organization of the KINSOL solver, while Section 4 summarizes its usage Section 5 describes a preconditioner module, Section ...
Date: July 1, 1998
Creator: Taylor, A. G., LLNL
Partner: UNT Libraries Government Documents Department

Nuclear criticality safety aspects of gaseous uranium hexafluoride (UF{sub 6}) in the diffusion cascade

Description: This paper determines the nuclear safety of gaseous UF{sub 6} in the current Gaseous Diffusion Cascade and auxiliary systems. The actual plant safety system settings for pressure trip points are used to determine the maximum amount of HF moderation in the process gas, as well as the corresponding atomic number densities. These inputs are used in KENO V.a criticality safety models which are sized to the actual plant equipment. The ENO V.a calculation results confirm nuclear safety of gaseous UF{sub 6} in plant operations..
Date: April 1, 1997
Creator: Huffer, J.E.
Partner: UNT Libraries Government Documents Department

KIVA-3V: A block-structured KIVA program for engines with vertical or canted valves

Description: This report describes an extended version of KIVA-3, known as KIVA-3V, that can model any number of vertical or canted valves in the cylinder head of an internal combustion (IC) engine. The valves are treated as solid objects that move through the mesh using the familiar snapper technique used for piston motion in KIVA-3. Because the valve motion is modeled exactly, and the valve shapes are as exact as the grid resolution will allow, the accuracy of the valve model is commensurate with that of the rest of the program. Other new features in KIVA-3V include a particle-based liquid wall film model, a new sorting subroutine that is linear in the number of nodes and preserves the original storage sequence, a mixing-controlled turbulent combustion model, and an optional RNG {kappa}-{epsilon} turbulence model. All features and capabilities of the original KIVA-3 have been retained. The grid generator, K3PREP, has been expanded to support the generation of grids with valves, along with the shaping of valve ports and runners. Graphics output options have also been expanded. The report discusses the new features, and includes four examples of grids with vertical and canted valves that are representative of IC engines in use today.
Date: July 1, 1997
Creator: Amsden, A.A.
Partner: UNT Libraries Government Documents Department

A parallel implementation of kriging with a trend

Description: This paper describes the parallelization of the GSLIB ktb3dm code. The code is parallelized using the message passing paradigm, Parallel Virtual Machine (PVM), under a Multiple Instructions, Multiple Data (MIMD) architecture. The code performance is analyzed using different grid sizes of 5x5x1, 50x50x1, 100x100x1 and 500x500x1 with 1, 2, 4, 8 and in some cases 16 processors on the Cray T3D supercomputer. The parallelization effort focused on the main kriging do loop. The results confirm that there is a substantial benefit to be derived in terms of CPU time savings (or execution speed) by using the parallel version of the code, especially when considering larger grids. Additionally, speed-up and scalability analyses show that actual speed-up is close to theoretical, while the code scales appropriately within the 1 to 16 processor range tested. The kriging of a quarter-million grid cell system fell from over 9 CPU minutes on one Cray T3D processor to about 1.25 CPU minutes on 16 processors on the same machine.
Date: November 1, 1997
Creator: Gajraj, A.; Joubert, W. & Jones, J.
Partner: UNT Libraries Government Documents Department

KENO3D Visualization Tool for KENO V.a and KENO-VI Geometry Models

Description: Criticality safety analyses often require detailed modeling of complex geometries. Effective visualization tools can enhance checking the accuracy of these models. This report describes the KENO3D visualization tool developed at the Oak Ridge National Laboratory (ORNL) to provide visualization of KENO V.a and KENO-VI criticality safety models. The development of KENO3D is part of the current efforts to enhance the SCALE (Standardized Computer Analyses for Licensing Evaluations) computer software system.
Date: June 1, 2000
Creator: Horwedel, J. E. & Bowman, S. M.
Partner: UNT Libraries Government Documents Department

The Kull IMC package

Description: We describe the Kull IMC package, and Implicit Monte Carlo Program written for use in A and X division radiation hydro codes. The Kull IMC has been extensively tested. Written in C++ and using genericity via the template feature to allow easy integration into different codes, the Kull IMC currently runs coupled radiation hydrodynamic problems in 2 different 3D codes. A stand-alone version also exists, which has been parallelized with mesh replication. This version has been run on up to 384 processors on ASCI Blue Pacific.
Date: October 1, 1998
Creator: Gentile, N A; Keen,N & Rathkopf, J
Partner: UNT Libraries Government Documents Department

Large-signal klystron simulations using KLSC

Description: The authors describe large-signal klystron simulations using the particle-in-cell code KLSC. This code uses the induced-current model to describe the steady-state cavity modulations and resulting rf fields, and advances the space-charge fields through maxwell`s equations. In this paper, an eight-cavity, high-power S-band klystron simulation is used to highlight various aspects of this simulation technique. In particular, there are specific issues associated with modeling the input cavity, the gain circuit, and the large-signal circuit (including the output cavities), that have to be treated carefully.
Date: October 1, 1997
Creator: Carlsten, B. E. & Ferguson, P.
Partner: UNT Libraries Government Documents Department

Hydrogen as a zero-emission, high-efficiency fuel: Uniqueness, experiments and simulations

Description: The planned use of hydrogen as the energy carrier of the future introduces new challenges and opportunities, especially to the engine design community. Hydrogen is a bio-friendly fuel that can be produced from renewable resources and has no carbon dioxide combustion products; and in a properly designed ICE, almost zero NO{sub x} and hydrocarbon emissions can be achieved. Because of the unique properties of hydrogen combustion - in particular the highly wrinkled nature of the laminar flame front due to the preferential diffusion instability - modeling approaches for hydrocarbon gaseous fuels are not generally applicable to hydrogen combustion. This paper reports on the current progress to develop an engine design capability based on the KIVA family of codes for hydrogen-fueled, spark-ignited engines in support of the National Hydrogen Program. A turbulent combustion model, based on a modified eddy-turnover model in conjunction with an intake flow valve model, is found to describe well the efficiency and NO{sub x} emissions for an experimental engine over a wide range of ignition timings. The NO{sub x} emissions of this engine satisfy the Equivalent Zero Vehicle (EZEV) standard established by the California Resource Board.
Date: November 1, 1997
Creator: Johnson, N.L.
Partner: UNT Libraries Government Documents Department

An authentication infrastructure for today and tomorrow

Description: The Open Software Foundation`s Distributed Computing Environment (OSF/DCE) was originally designed to provide a secure environment for distributed applications. By combining it with Kerberos Version 5 from MIT, it can be extended to provide network security as well. This combination can be used to build both an inter and intra organizational infrastructure while providing single sign-on for the user with overall improved security. The ESnet community of the Department of Energy is building just such an infrastructure. ESnet has modified these systems to improve their interoperability, while encouraging the developers to incorporate these changes and work more closely together to continue to improve the interoperability. The success of this infrastructure depends on its flexibility to meet the needs of many applications and network security requirements. The open nature of Kerberos, combined with the vendor support of OSF/DCE, provides the infrastructure for today and tomorrow.
Date: June 1, 1996
Creator: Engert, D.E.
Partner: UNT Libraries Government Documents Department

Knob manager (KM) operators guide

Description: KM, Knob Manager, is a tool which enables the user to use the SUNDIALS knob box to adjust the settings of the control system. The followings are some features of KM: dynamic knob assignments with the user friendly interface; user-defined gain for individual knob; graphical displays for operating range and status of each process variable is assigned; backup and restore one or multiple process variable; save current settings to a file and recall the settings from that file in future.
Date: October 8, 1993
Partner: UNT Libraries Government Documents Department

Assurances associated with Monte Carlo code results

Description: All Monte Carlo computer codes have an uncertainty associated with the final result. This uncertainty (or standard deviation) is due to the sampling method inherent within the Monte Carlo technique. The basic assumptions required for the final result and uncertainty to be valid are (1) the random numbers used are truly random, (2) there is no correlation between histories, (3) the number of histories used is sufficient to represent the problem, and (4) the entire problem is adequately sampled. The first two assumptions are an integral are strongly dependent on how a problem is set up and the number of histories processed. These are items the user has direct control over. This paper examines six aspects of the KENO Monte Carlo code that affect the above-mentioned four assumptions.
Date: June 1, 1995
Creator: Hollenbach, D.F. & Petrie, L.M.
Partner: UNT Libraries Government Documents Department

Validation calculations in support of transportation safety analyses

Description: The Y-12 classified version of KENO-Va and the 27-group cross-section library from ENDF/B-IV have been validated for plutonium systems. Some biases in calculated k-effectives were observed. K-effectives averaged 1.5% high. Sufficient data are presented to derive a subcritical limit for any particular plutonium-bearing system.
Date: February 1, 1995
Creator: Primm, R. T. & Tollefson, D. A.
Partner: UNT Libraries Government Documents Department

KENO IV: an improved Monte Carlo criticality program

Description: KENO IV is a multigroup Monte Carlo criticality program written for the IBM 360 computers. It executes rapidly and is flexibly dimensioned so the allowed size of a problem (i.e., the number of energy groups, number of geometry cards, etc., are arbitrary) is limited only by the total data storage required. The input data, with the exception of cross sections, fission spectra and albedos, may be entered in free form. The geometry input is quite simple to prepare and complicated three-dimensional systems can often be described with a minimum of effort. The results calculated by KENO IV include k-effective, lifetime and generation time, energy-dependent leakages and absorptions, energy- and region-dependent fluxes and region-dependent fission densities. Criticality searches can be made on unit dimensions or on the number of units in an array. A summary of the theory utilized by KENO IV, a section describing the logical program flow, a compilation of the error messages printed by the code and a comprehensive data guide for preparing input to the code are presented. 14 references. (auth)
Date: November 1, 1975
Creator: Petrie, L.M. & Cross, N.F.
Partner: UNT Libraries Government Documents Department

Application of Monte Carlo criticality calculations to the Ames Laboratory Research Reactor

Description: >Thesis. The modeling of the Ames Laboratory Research Reactor core region and the input required to utilize the Monte Carlo computer code KENO for criticality calculations are described. Reactivity calculations in terms of k- effective were made for various reactor configurations and compared to measurements made on the actual reactor. (16 references) (auth)
Date: April 1, 1974
Creator: Hull, D.L.
Partner: UNT Libraries Government Documents Department