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Comparison of various NLTE codes in computing the charge-state populations of an argon plasma

Description: A comparison among nine computer codes shows surprisingly large differences where it had been believed that the theroy was well understood. Each code treats an argon plasma, optically thin and with no external photon flux; temperatures vary around 1 keV and ion densities vary from 6 x 10/sup 17/ cm/sup -3/ to 6 x 10/sup 21/ cm/sup -3/. At these conditions most ions have three or fewer bound electrons. The calculated populations of 0-, 1-, 2-, and 3-electron ions differ from code to code by typical factors of 2, in some cases by factors greater than 300. These differences depend as sensitively on how may Rydberg states a code allows as they do on variations among computed collision rates. 29 refs., 23 figs.
Date: November 1, 1984
Creator: Stone, S.R. & Weisheit, J.C.
Partner: UNT Libraries Government Documents Department

Fluid permeability of deformable fracture networks

Description: The authors consider the problem of defining the fracture permeability tensor for each grid lock in a rock mass from maps of natural fractures. For this purpose they implement a statistical model of cracked rock due to M. Oda [1985], where the permeability tensor is related to the crack geometry via a volume average of the contribution from each crack in the population. In this model tectonic stress is implicitly coupled to fluid flow through an assumed relationship between crack aperture and normal stress across the crack. The authors have included the following enhancements to the basic model: (1) a realistic model of crack closure under stress has been added along with the provision to apply tectonic stresses to the fracture system in any orientation, the application of stress results in fracture closure and consequently a reduction in permeability; (2) the fracture permeability can be superimposed onto an arbitrary anisotropic matrix permeability; (3) the fracture surfaces are allowed to slide under the application of shear stress, causing fractures to dilate and result in a permeability increase. Through an example, the authors demonstrate that significant changes in permeability magnitudes and orientations are possible when tectonic stress is applied to a fracture system.
Date: April 1, 1997
Creator: Brown, S.R. & Bruhn, R.L.
Partner: UNT Libraries Government Documents Department

Improving productivity with a CCC tool kit. [Utility macros]

Description: A typical utility macro tool set is described. Included are SIMPORT and SEXPORT that provide syntax-directed import and export, EDIT-HOST which permits CCC resident texts to be edited with a host editor, INITIATE-LOGIN which automatically executes a hierarchy of user- and manager-defined login texts, and BATCH whicn permits CCC macros to be executed in batch mode from within CCC.
Date: January 1, 1987
Creator: Cort, G.
Partner: UNT Libraries Government Documents Department

Intercomparison of low-frequency variability of the global 200 hPa circulation for AMIP simulations

Description: In the Atmospheric Model Intercomparison Project (AMIP) a number of GCMs are integrated for a 10 year period, 1979-1988, all using the same monthly mean sea surface temperature (SST). This permits a useful intercomparison of the response of the models to the imposed SST. The variables used here for the intercomparison are the 200 hPa divergence and streamfunction. The data used are in the form of monthly averages and are filtered to a spatial resolution of T10, although the actual spatial resolution of the models varies from R15 to T42. The data are manipulated in this manner to concentrate on the low frequency, large scale response. The tools of the analysis are principal components analysis (PCA) and common principal components (CPC). These analyses are carried out on the 120 months of data with the seasonal cycle removed and in the case of the streamfunction with the zonal average also removed. The 1979-1988 period encompasses two El Nino/Southern Oscillation (ENSO) events (1982/83 and 1986/87), and as could be expected the ENSO characteristic response has a prominent impact in the model simulations.
Date: March 1, 1996
Creator: Boyle, J.S.
Partner: UNT Libraries Government Documents Department


Description: This is a brief description of a computer program which was written by Oleh Weres to generate discrete grids for IFD* type computer programs. The output of the program includes data which can be used directly for input to the program SHAFT78. The program is specifically intended for large-scale two or three-dimensional reservoir simulation. The program requires, as input, the x, y, z coordinates of the discrete element locations being used to specify a particular reservoir's geological system. From the list of element locations, the program finds the midpoints of lines joining adjacent elements. At each midpoint the program constructs a perpendicular plane. The intersections of the planes in the three-space defines an irregular (in general) n-sided polyhedron around each element center. In two-dimensions the program produces a unique 'tiling' which has polygons with all faces perpendicular to the lines joining adjacent elements. The areas between adjoining elements and the volume of each element are calculated. The end result, in general, is a three-dimensional grid of n-sided polyhedra for which the element locations, the connecting (flow) areas, and the element volumes are all known. Since the grids are finite the program must have information about the boundary of the grid. This is supplied as a set of 'dummy' elements which are used only to limit the extent of the grid and are not intended for use in the reservoir simulation.
Date: June 1, 1978
Creator: Weres, O. & Schroeder, R.C.
Partner: UNT Libraries Government Documents Department

User Instructions for the CiderF Individual Dose Code and Associated Utility Codes

Description: Historical activities at facilities producing nuclear materials for weapons released radioactivity into the air and water. Past studies in the United States have evaluated the release, atmospheric transport and environmental accumulation of 131I from the nuclear facilities at Hanford in Washington State and the resulting dose to members of the public (Farris et al. 1994). A multi-year dose reconstruction effort (Mokrov et al. 2004) is also being conducted to produce representative dose estimates for members of the public living near Mayak, Russia, from atmospheric releases of 131I at the facilities of the Mayak Production Association. The approach to calculating individual doses to members of the public from historical releases of airborne 131I has the following general steps: • Construct estimates of releases 131I to the air from production facilities. • Model the transport of 131I in the air and subsequent deposition on the ground and vegetation. • Model the accumulation of 131I in soil, water and food products (environmental media). • Calculate the dose for an individual by matching the appropriate lifestyle and consumption data for the individual to the concentrations of 131I in environmental media at their residence location. A number of computer codes were developed to facilitate the study of airborne 131I emissions at Hanford. The RATCHET code modeled movement of 131I in the atmosphere (Ramsdell Jr. et al. 1994). The DECARTES code modeled accumulation of 131I in environmental media (Miley et al. 1994). The CIDER computer code estimated annual doses to individuals (Eslinger et al. 1994) using the equations and parameters specific to Hanford (Snyder et al. 1994). Several of the computer codes developed to model 131I releases from Hanford are general enough to be used for other facilities. This document provides user instructions for computer codes calculating doses to members of the public from atmospheric 131I ...
Date: August 30, 2013
Creator: Eslinger, Paul W. & Napier, Bruce A.
Partner: UNT Libraries Government Documents Department

Damage estimates from long-term structural analysis of a wind turbine in a US wind farm environment

Description: Time-domain simulations of the loads on wind energy conversion systems have been hampered in the past by the relatively long computational times for nonlinear structural analysis codes. However, recent advances in both the level of sophistication and computational efficiency of available computer hardware and the codes themselves now permit long-term simulations to be conducted in reasonable times. Thus, these codes provide a unique capability to evaluate the spectral content of the fatigue loads on a turbine. To demonstrate these capabilities, a Micon 65/13 turbine is analyzed using the YawDyn and the ADAMS dynamic analysis codes. The SNLWIND-3D simulator and measured boundary conditions are used to simulate the inflow environment that can be expected during a single, 24-hour period by a turbine residing in Row 41 of a wind farm located in San Gorgonio Pass, California. Also, long-term simulations (up to 8 hours of simulated time) with constant average inflow velocities are used to better define the characteristics of the fatigue load on the turbine. Damage calculations, using the LIFE2 fatigue analysis code and the MSU/DOE fatigue data base for composite materials, are then used to determine minimum simulation times for consistent estimates of service lifetimes.
Date: October 1, 1996
Creator: Kelley, N.D. & Sutherland, H.J.
Partner: UNT Libraries Government Documents Department

System description: IVY

Description: IVY is a verified theorem prover for first-order logic with equality. It is coded in ACL2, and it makes calls to the theorem prover Otter to search for proofs and to the program MACE to search for countermodels. Verifications of Otter and MACE are not practical because they are coded in C. Instead, Otter and MACE give detailed proofs and models that are checked by verified ACL2 programs. In addition, the initial conversion to clause form is done by verified ACL2 code. The verification is done with respect to finite interpretations.
Date: February 4, 2000
Creator: McCune, W. & Shumsky, O.
Partner: UNT Libraries Government Documents Department

User News. Volume 17, Number 1 -- Spring 1996

Description: This is a newsletter for users of the DOE-2, PowerDOE, SPARK, and BLAST building energy simulation programs. The topics for the Spring 1996 issue include the SPARK simulation environment, DOE-2 validation, listing of free fenestration software from LBNL, Web sites for building energy efficiency, the heat balance method of calculating building heating and cooling loads.
Date: July 1, 1996
Partner: UNT Libraries Government Documents Department

State-of-the-art software for window energy-efficiency rating and labeling

Description: Measuring the thermal performance of windows in typical residential buildings is an expensive proposition. Not only is laboratory testing expensive, but each window manufacturer typically offers hundreds of individual products, each of which has different thermal performance properties. With over a thousand window manufacturers nationally, a testing-based rating system would be prohibitively expensive to the industry and to consumers. Beginning in the early 1990s, simulation software began to be used as part of a national program for rating window U-values. The rating program has since been expanded to include Solar Hear Gain Coefficients and is now being extended to annual energy performance. This paper describes four software packages available to the public from Lawrence Berkeley National Laboratory (LBNL). These software packages are used to evaluate window thermal performance: RESFEN (for evaluating annual energy costs), WINDOW (for calculating a product`s thermal performance properties), THERM (a preprocessor for WINDOW that determines two-dimensional heat-transfer effects), and Optics (a preprocessor for WINDOW`s glass database). Software not only offers a less expensive means than testing to evaluate window performance, it can also be used during the design process to help manufacturers produce windows that will meet target specifications. In addition, software can show small improvements in window performance that might not be detected in actual testing because of large uncertainties in test procedures.
Date: July 1, 1998
Creator: Arasteh, D.; Finlayson, E.; Huang, J.; Mitchell, R.; Rubin, M. & Huizenga, C.
Partner: UNT Libraries Government Documents Department

The Application Programming Interface for the PVMEXEC Program and Associated Code Coupling System

Description: This report describes the Application Programming Interface for the PVMEXEC program and the code coupling systems that it implements. The information in the report is intended for programmers wanting to add a new code into the coupling system.
Date: March 1, 2005
Creator: III, Walter L. Weaver
Partner: UNT Libraries Government Documents Department