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in subjects: "Calculation Methods"

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Source-jerk analysis using a semi-explicit inverse kinetic technique

A method is proposed for measuring the effective reproduction factor, k, in subcritical systems. The method uses the transient response of a subcritical system to the sudden removal of an extraneous neutron source (i.e., a source jerk). The response is analyzed using an inverse kinetic technique that least-squares fits the exact analytical solution corresponding to a source-jerk transient as derived from the point-reactor model. It has been found that the technique can provide an accurate means… more

Date: January 1, 1985

Creator: Spriggs, G.D. & Pederson, R.A.

Item Type: Article

Partner: UNT Libraries Government Documents Department

open access

A theoretical prediction of critical heat flux in subcooled pool boiling during power transients

Understanding and predicting critical heat flux (CHF) behavior during steady-state and transient conditions are of fundamenatal interest in the design, operation, safety of boiling and two-phase flow devices. This paper discusses the results of a comprehensive theoretical study made specifically to model transient CHF behavior in subcooled pool boiling. This study is based upon a simplified steady-state CHF model in terms of the vapor mass growth period. The results obtained from this theory in… more

Date: January 1, 1988

Creator: Pasamehmetoglu, K. O.; Nelson, R. A. & Gunnerson, F. S.

Item Type: Article

Partner: UNT Libraries Government Documents Department

open access

''Figure of merit'' Q/. mu. /sub max//sup 2/3/, for beam transport through periodic focussing systems

A discussion is given of a figure of merit indicative of the stability of high intensity beam transport systems. A table is provided giving this quantity under various conditions, and the limits for solenoidal focusing systems are obtained. (PMA)

Date: November 23, 1977

Creator: Laslett, L.J.

Item Type: Article

Partner: UNT Libraries Government Documents Department

open access

Statistical methods for including two-body forces in large system calculations

Large systems of interacting particles are often treated by assuming that the effect on any one particle of the remaining N-1 may be approximated by an average potential. This approach reduces the problem to that of finding the bound-state solutions for a particle in a potential; statistical mechanics is then used to obtain the properties of the many-body system. In some physical systems this approach may not be acceptable, because the two-body force component cannot be treated in this one-body… more

Date: July 1, 1980

Creator: Grimes, S.M.

Item Type: Report

Partner: UNT Libraries Government Documents Department

open access

Energy-consumption modelling

A highly sophisticated and accurate approach is described to compute on an hourly or daily basis the energy consumption for space heating by individual buildings, urban sectors, and whole cities. The need for models and specifically weather-sensitive models, composite models, and space-heating models are discussed. Development of the Colorado State University Model, based on heat-transfer equations and on a heuristic, adaptive, self-organizing computation learning approach, is described. Result… more

Date: April 1980

Creator: Reiter, Elmar R.

Item Type: Article

Partner: UNT Libraries Government Documents Department

open access

Nuclear fuel cycle facility accident analysis handbook

The Accident Analysis Handbook (AAH) covers four generic facilities: fuel manufacturing, fuel reprocessing, waste storage/solidification, and spent fuel storage; and six accident types: fire, explosion, tornado, criticality, spill, and equipment failure. These are the accident types considered to make major contributions to the radiological risk from accidents in nuclear fuel cycle facility operations. The AAH will enable the user to calculate source term releases from accident scenarios manual… more

Date: unknown

Creator: Ayer, J. E.; Clark, A. T.; Loysen, P.; Ballinger, M. Y.; Mishima, J.; Owczarski, P. C. et al.

Item Type: Report

Partner: UNT Libraries Government Documents Department

open access

Further considerations of critical heat flux in saturated pool boiling during power transients

In this paper, we further evaluate our previously postulated transient CHF model. First, we verify the steady-state CHF model on which the transient model is based by using recent macrolayer-thickness data. We also include the effect of thermal storage in the heater that we previously neglected. The use of a simplified approach in the prediction of the instantaneous surface heat flux for given pwoer generation rates considerably improves the predictive capability of the transient critical heat-… more

Date: January 1, 1988

Creator: Pasamehmetoglu, K.O. & Nelson, R.A.

Item Type: Article

Partner: UNT Libraries Government Documents Department

open access

Simple empirical method for estimating the performance of a passive solar heated building of the thermal storage wall type

Two methods are presented for estimating the annual solar heating performance of a building utilizing a passive thermal storage wall of the Trombe wall or water wall type with or without night insulation and with or without a reflector. The method is accurate to +-3% as compared with hour-by-hour computer simulations.

Date: January 1, 1978

Creator: Balcomb, J.D. & McFarland, R.D.

Item Type: Article

Partner: UNT Libraries Government Documents Department

open access

Solar photovoltaic applications seminar: design, installation and operation of small, stand-alone photovoltaic power systems

This seminar material was developed primarily to provide solar photovoltaic (PV) applied engineering technology to the Federal community. An introduction to photoconductivity, semiconductors, and solar photovoltaic cells is included along with a demonstration of specific applications and application identification. The seminar details general systems design and incorporates most known information from industry, academia, and Government concerning small solar cell power system design engineering… more

Date: July 1, 1980

Item Type: Report

Partner: UNT Libraries Government Documents Department

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Development of nuclear models for higher energy calculations

Two nuclear models for higher energy calculations have been developed in the regions of high and low energy transfer, respectively. In the former, a relativistic hybrid-type preequilibrium model is compared with data ranging from 60 to 800 MeV. Also, the GNASH exciton preequilibrium-model code with higher energy improvements is compared with data at 200 and 318 MeV. In the region of low energy transfer, nucleon-nucleus scattering is predominately a direct reaction involving quasi-elastic collis… more

Date: January 1, 1988

Creator: Bozoian, M.; Siciliano, E. R. & Smith, R. D.

Item Type: Article

Partner: UNT Libraries Government Documents Department

open access

Multilayer optical elements for generation and analysis of circularly polarized x-rays

Calculations of the relative phase changes of {sigma} and {pi} electric field components on Bragg reflection from and transmission through multilayers are presented. Large relative phase changes can be calculated in certain cases, which may lead to utility of multilayers as quarter-wave plates for generation and analysis of circularly polarized soft x-radiation. Similar behavior may be expected for perfect crystals in the hard x-ray range. 24 refs., 4 figs.

Date: August 1, 1989

Creator: Kortright, J.B. & Underwood, J.H.

Item Type: Article

Partner: UNT Libraries Government Documents Department

open access

Notes on Luminosity Variation at ISABELLE

In the present ISABELLE design, the luminosity at each insertion will be the same, unless special efforts are taken to get a low-..beta.. insertion or reduced crossing angle. These can only change the luminosity by factors of 2 to 4 from insertion to insertion. An estimation of the range of desired luminosities is given.

Date: October 19, 1977

Creator: Herrera, J. C.; Marx, M.; Roe, B. & Rosenberg, E. I.

Item Type: Article

Partner: UNT Libraries Government Documents Department

open access

Preliminary requirements for thermal storage subsystems in solar thermal applications

Methodologies for the analysis of value and comparing thermal storage concepts are presented. Value is a measure of worth and is determined by the cost of conventional fuel systems. Value data for thermal storage in large solar thermal electric power applications are presented. Thermal storage concepts must be compared when all are performing the same mission. A method for doing that analysis, called the ranking index, is derived. Necessary data to use the methodology are included.

Date: April 1, 1980

Creator: Copeland, R.J.

Item Type: Report

Partner: UNT Libraries Government Documents Department

open access

Three-dimensional thermal analysis of a baseline spent fuel repository

A three-dimensional thermal analysis has been performed using finite difference techniques to determine the near-field response of a baseline spent fuel repository in a deep geologic salt medium. A baseline design incorporates previous thermal modeling experience and OWI recommendations for areal thermal loading in specifying the waste form properties, package details, and emplacement configuration. The base case in this thermal analysis considers one 10-year old PWR spent fuel assembly emplace… more

Date: June 5, 1980

Creator: Altenbach, T.J. & Lowry, W.E.

Item Type: Article

Partner: UNT Libraries Government Documents Department

open access

A theoretical prediction of critical heat flux in forced convection boiling during power transients

In this paper, a theoretical prediction of critical heat flux (CHF) during power transients in forced convective boiling is presented. The analysis is restricted to the departure from nucleate boiling (DNB) type of CHF at low qualities. The developed theory is compared with the experimental data available in the literature. The agreement is favorable. The results are discussed in terms of the various parameters affecting the transient CHF. This new model also is compared with the semi-empirical… more

Date: January 1, 1988

Creator: Pasamehmetoglu, K.O.; Nelson, R.A. & Gunnerson, F.S.

Item Type: Article

Partner: UNT Libraries Government Documents Department

open access

Performance estimation using correlation methods

Correlation methods of prediction have advantages in greatly simplifying the time and complexity of performance predictions of passive solar buildings but are severely constrained in the number of variables which can be considered. Their accuracy is generally adequate for design purposes provided they are applied to buildings which correspond reasonably closely to the reference designs used in developing the correlations. The most simplified correlation procedures (such as the SLR method) are a… more

Date: January 1, 1980

Creator: Balcomb, J. D.

Item Type: Article

Partner: UNT Libraries Government Documents Department

open access

Estimates of post-acceleration longitudinal bunch compression

A simple analytic method is developed, based on physical approximations, for treating transient implosive longitudinal compression of bunches of heavy ions in an accelerator system for ignition of inertial-confinement fusion pellet targets. Parametric dependences of attainable compressions and of beam path lengths and times during compression are indicated for ramped pulsed-gap lines, rf systems in storage and accumulator rings, and composite systems, including sections of free drift. It appear… more

Date: November 25, 1977

Creator: Judd, D.L.

Item Type: Article

Partner: UNT Libraries Government Documents Department

open access

Prediction Approach to Multistage Sampling When Cluster Sizes Are Unknown

A model for two-stage cluster sampling when sample cluster sizes are unknown is used to derive an optimal (model-based) estimator for the population total and to determine robust sampling strategies. In an empirical study using 1970 and 1980 census data for Los Angeles and surrounding counties, comparisons are made between the model based estimator and conventional estimators. The results favor the new estimator over those derived from randomization theory. In addition, the empirical study show… more

Date: January 1, 1985

Creator: Kelly, E. J. & Cumberland, W. G.

Item Type: Article

Partner: UNT Libraries Government Documents Department

open access

Lattice calculations of electroweak decay amplitudes

I review the progress made during the last year in lattice calculations of weak and electromagnetic amplitudes. 32 refs., 9 figs., 2 tabs.

Date: November 1, 1989

Creator: Sharpe, S.R.

Item Type: Article

Partner: UNT Libraries Government Documents Department

open access

The Collective Vector method in nuclear and atomic physics

We present a brief review of the method of the Collective Vector (CV) and its use in conjunction with the Lanczos algorithm (LA). The combination of these two ideas produces a method for contracting super-large hamiltonians (up to 10{sup 6} {times} 10{sup 6}) by factors of 1000 or more. The contracted hamiltonians, which we call quasi-hamiltonians, typically have dimensions of the order of 10{sup 2} {times} 10{sup 2} and produce corresponding quasi-spectra with associated quasi-eigenfunctions w… more

Date: December 1, 1989

Creator: Bloom, S.D.

Item Type: Article

Partner: UNT Libraries Government Documents Department

open access

Status of theories for calculations of production cross sections of long-lived radionuclides

The theories discussed in this paper are confined to those currently being used or considered for the calculation of activation cross sections. The theories are the same regardless of whether the activation product is long lived or short lived. However, the cross sections for the generation of long-lived radionuclides are more difficult or expensive to measure, hence there are fewer data available and the requirement on the predictive capability of the theories used is more stringent. It is cle… more

Date: January 1, 1989

Creator: Fu, C.Y.

Item Type: Article

Partner: UNT Libraries Government Documents Department

open access

Comparing the Floating Point Systems, Inc. AP-190L to representative scientific computers: some benchmark results

Results are presented of comparative timing tests made by running a typical FORTRAN physics simulation code on the following machines: DEC PDP-10 with KI processor; DEC PDP-10, KI processor, and FPS AP-190L; CDC 7600; and CRAY-1. Factors such as DMA overhead, code size for the AP-190L, and the relative utilization of floating point functional units for the different machines are discussed. 1 table.

Date: March 27, 1980

Creator: Brengle, T.A. & Maron, N.

Item Type: Article

Partner: UNT Libraries Government Documents Department

open access

Evaluation of solar mirror figure by moire contouring

Moire topography is applied to the figure assessment of solar mirrors. The technique is demonstrated on component facets of a six-meter diameter, four-meter focal length, parabolic dish collector. The relative ease of experimental implementation and subsequent data analysis suggests distinct advantages over the more established laser ray trace or BCS/ICS technique for many applications. The theoretical and experimental considerations necessary to fully implement moire topography on mirror surfa… more

Date: June 1, 1980

Creator: Griffin, J.W. & Lind, M.A.

Item Type: Report

Partner: UNT Libraries Government Documents Department

open access

General Chemistry Division quarterly report, July--September 1977

Analytical research and development work is reported on multielement analysis, time-resolved spectroscopy, fluorescence analysis, ionization potential of NP, excited state chemistry, polarized x ray sources, potentiometric titration of Na, determination of TATB in DMSO, determination of nitrobenzene in TATB, analysis of explosive composites, mass spectrometer automation, mass spectra calculation, solids formation in geothermal brine, water quality laboratory automation, aerosol coagulation, and… more

Date: November 30, 1977

Creator: Harrar, J.E. (ed.)

Item Type: Report

Partner: UNT Libraries Government Documents Department