NASA Technical Reports Server (NTRS)
Pan, Y. S.; Drummond, J. P.; Mcclinton, C. R.
1978-01-01
Two parabolic flow computer programs, SHIP (a finite-difference program) and COMOC (a finite-element program), are used for predicting three-dimensional turbulent reacting flow fields in supersonic combustors. The theoretical foundation of the two computer programs are described, and then the programs are applied to a three-dimensional turbulent mixing experiment. The cold (nonreacting) flow experiment was performed to study the mixing of helium jets with a supersonic airstream in a rectangular duct. Surveys of the flow field at an upstream were used as the initial data by programs; surveys at a downstream station provided comparison to assess program accuracy. Both computer programs predicted the experimental results and data trends reasonably well. However, the comparison between the computations from the two programs indicated that SHIP was more accurate in computation and more efficient in both computer storage and computing time than COMOC.
NASA Technical Reports Server (NTRS)
Jumper, S. J.
1979-01-01
A method was developed for predicting the potential flow velocity field at the plane of a propeller operating under the influence of a wing-fuselage-cowl or nacelle combination. A computer program was written which predicts the three dimensional potential flow field. The contents of the program, its input data, and its output results are described.
Student Use of Physics to Make Sense of Incomplete but Functional VPython Programs in a Lab Setting
NASA Astrophysics Data System (ADS)
Weatherford, Shawn A.
2011-12-01
Computational activities in Matter & Interactions, an introductory calculus-based physics course, have the instructional goal of providing students with the experience of applying the same set of a small number of fundamental principles to model a wide range of physical systems. However there are significant instructional challenges for students to build computer programs under limited time constraints, especially for students who are unfamiliar with programming languages and concepts. Prior attempts at designing effective computational activities were successful at having students ultimately build working VPython programs under the tutelage of experienced teaching assistants in a studio lab setting. A pilot study revealed that students who completed these computational activities had significant difficultly repeating the exact same tasks and further, had difficulty predicting the animation that would be produced by the example program after interpreting the program code. This study explores the interpretation and prediction tasks as part of an instructional sequence where students are asked to read and comprehend a functional, but incomplete program. Rather than asking students to begin their computational tasks with modifying program code, we explicitly ask students to interpret an existing program that is missing key lines of code. The missing lines of code correspond to the algebraic form of fundamental physics principles or the calculation of forces which would exist between analogous physical objects in the natural world. Students are then asked to draw a prediction of what they would see in the simulation produced by the VPython program and ultimately run the program to evaluate the students' prediction. This study specifically looks at how the participants use physics while interpreting the program code and creating a whiteboard prediction. This study also examines how students evaluate their understanding of the program and modification goals at the beginning of the modification task. While working in groups over the course of a semester, study participants were recorded while they completed three activities using these incomplete programs. Analysis of the video data showed that study participants had little difficulty interpreting physics quantities, generating a prediction, or determining how to modify the incomplete program. Participants did not base their prediction solely from the information from the incomplete program. When participants tried to predict the motion of the objects in the simulation, many turned to their knowledge of how the system would evolve if it represented an analogous real-world physical system. For example, participants attributed the real-world behavior of springs to helix objects even though the program did not include calculations for the spring to exert a force when stretched. Participants rarely interpreted lines of code in the computational loop during the first computational activity, but this changed during latter computational activities with most participants using their physics knowledge to interpret the computational loop. Computational activities in the Matter & Interactions curriculum were revised in light of these findings to include an instructional sequence of tasks to build a comprehension of the example program. The modified activities also ask students to create an additional whiteboard prediction for the time-evolution of the real-world phenomena which the example program will eventually model. This thesis shows how comprehension tasks identified by Palinscar and Brown (1984) as effective in improving reading comprehension are also effective in helping students apply their physics knowledge to interpret a computer program which attempts to model a real-world phenomena and identify errors in their understanding of the use, or omission, of fundamental physics principles in a computational model.
NASA Technical Reports Server (NTRS)
Egolf, T. Alan; Anderson, Olof L.; Edwards, David E.; Landgrebe, Anton J.
1988-01-01
A user's manual for the computer program developed for the prediction of propeller-nacelle aerodynamic performance reported in, An Analysis for High Speed Propeller-Nacelle Aerodynamic Performance Prediction: Volume 1 -- Theory and Application, is presented. The manual describes the computer program mode of operation requirements, input structure, input data requirements and the program output. In addition, it provides the user with documentation of the internal program structure and the software used in the computer program as it relates to the theory presented in Volume 1. Sample input data setups are provided along with selected printout of the program output for one of the sample setups.
ERIC Educational Resources Information Center
Garmon, Linda
1981-01-01
Describes the features of various computer chemistry programs. Utilization of computer graphics, color, digital imaging, and other innovations are discussed in programs including those which aid in the identification of unknowns, predict whether chemical reactions are feasible, and predict the biological activity of xenobiotic compounds. (CS)
An experimental and theoretical investigation of deposition patterns from an agricultural airplane
NASA Technical Reports Server (NTRS)
Morris, D. J.; Croom, C. C.; Vandam, C. P.; Holmes, B. J.
1984-01-01
A flight test program has been conducted with a representative agricultural airplane to provide data for validating a computer program model which predicts aerially applied particle deposition. Test procedures and the data from this test are presented and discussed. The computer program features are summarized, and comparisons of predicted and measured particle deposition are presented. Applications of the computer program for spray pattern improvement are illustrated.
Verification of MICNOISE computer program for the prediction of highway noise
DOT National Transportation Integrated Search
1974-01-01
The objectives of this study were to verify the computer program used by the Virginia Department of Highways to predict highway sound pressure levels, to determine whether the accuracy and usefulness of the program could be improved, and to make reco...
NASA Technical Reports Server (NTRS)
Nesbitt, James A.
2001-01-01
A finite-difference computer program (COSIM) has been written which models the one-dimensional, diffusional transport associated with high-temperature oxidation and interdiffusion of overlay-coated substrates. The program predicts concentration profiles for up to three elements in the coating and substrate after various oxidation exposures. Surface recession due to solute loss is also predicted. Ternary cross terms and concentration-dependent diffusion coefficients are taken into account. The program also incorporates a previously-developed oxide growth and spalling model to simulate either isothermal or cyclic oxidation exposures. In addition to predicting concentration profiles after various oxidation exposures, the program can also be used to predict coating life based on a concentration dependent failure criterion (e.g., surface solute content drops to 2%). The computer code is written in FORTRAN and employs numerous subroutines to make the program flexible and easily modifiable to other coating oxidation problems.
Prediction of Combustion Gas Deposit Compositions
NASA Technical Reports Server (NTRS)
Kohl, F. J.; Mcbride, B. J.; Zeleznik, F. J.; Gordon, S.
1985-01-01
Demonstrated procedure used to predict accurately chemical compositions of complicated deposit mixtures. NASA Lewis Research Center's Computer Program for Calculation of Complex Chemical Equilibrium Compositions (CEC) used in conjunction with Computer Program for Calculation of Ideal Gas Thermodynamic Data (PAC) and resulting Thermodynamic Data Base (THDATA) to predict deposit compositions from metal or mineral-seeded combustion processes.
Improved neutron activation prediction code system development
NASA Technical Reports Server (NTRS)
Saqui, R. M.
1971-01-01
Two integrated neutron activation prediction code systems have been developed by modifying and integrating existing computer programs to perform the necessary computations to determine neutron induced activation gamma ray doses and dose rates in complex geometries. Each of the two systems is comprised of three computational modules. The first program module computes the spatial and energy distribution of the neutron flux from an input source and prepares input data for the second program which performs the reaction rate, decay chain and activation gamma source calculations. A third module then accepts input prepared by the second program to compute the cumulative gamma doses and/or dose rates at specified detector locations in complex, three-dimensional geometries.
Study of inducer load and stress, volume 2
NASA Technical Reports Server (NTRS)
1972-01-01
A program of analysis, design, fabrication and testing has been conducted to develop computer programs for predicting rocket engine turbopump inducer hydrodynamic loading, stress magnitude and distribution, and vibration characteristics. Methods of predicting blade loading, stress, and vibration characteristics were selected from a literature search and used as a basis for the computer programs. An inducer, representative of typical rocket engine inducers, was designed, fabricated, and tested with special instrumentation selected to provide measurements of blade surface pressures and stresses. Data from the tests were compared with predicted values and the computer programs were revised as required to improve correlation. For Volume 1 see N71-20403. For Volume 2 see N71-20404.
NASA Technical Reports Server (NTRS)
Nesbitt, James A.
2000-01-01
A finite-difference computer program (COSIM) has been written which models the one-dimensional, diffusional transport associated with high-temperature oxidation and interdiffusion of overlay-coated substrates. The program predicts concentration profiles for up to three elements in the coating and substrate after various oxidation exposures. Surface recession due to solute loss is also predicted. Ternary cross terms and concentration-dependent diffusion coefficients are taken into account. The program also incorporates a previously-developed oxide growth and spalling model to simulate either isothermal or cyclic oxidation exposures. In addition to predicting concentration profiles after various oxidation exposures, the program can also be used to predict coating fife based on a concentration dependent failure criterion (e.g., surface solute content drops to two percent). The computer code, written in an extension of FORTRAN 77, employs numerous subroutines to make the program flexible and easily modifiable to other coating oxidation problems.
Aircraft noise source and computer programs - User's guide
NASA Technical Reports Server (NTRS)
Crowley, K. C.; Jaeger, M. A.; Meldrum, D. F.
1973-01-01
The application of computer programs for predicting the noise-time histories and noise contours for five types of aircraft is reported. The aircraft considered are: (1) turbojet, (2) turbofan, (3) turboprop, (4) V/STOL, and (5) helicopter. Three principle considerations incorporated in the design of the noise prediction program are core effectiveness, limited input, and variable output reporting.
DOT National Transportation Integrated Search
1975-01-01
This is a continuation of an earlier report in which the MICNOISE computer program for the prediction of highway noise was evaluated. The outputs of the MICNOISE program are the L50 and LI0 sound pressure levels, i.e., those levels experienced 50% an...
NASA Technical Reports Server (NTRS)
Kleckner, R. J.; Rosenlieb, J. W.; Dyba, G.
1980-01-01
The results of a series of full scale hardware tests comparing predictions of the SPHERBEAN computer program with measured data are presented. The SPHERBEAN program predicts the thermomechanical performance characteristics of high speed lubricated double row spherical roller bearings. The degree of correlation between performance predicted by SPHERBEAN and measured data is demonstrated. Experimental and calculated performance data is compared over a range in speed up to 19,400 rpm (0.8 MDN) under pure radial, pure axial, and combined loads.
Predicting Computer Science Ph.D. Completion: A Case Study
ERIC Educational Resources Information Center
Cox, G. W.; Hughes, W. E., Jr.; Etzkorn, L. H.; Weisskopf, M. E.
2009-01-01
This paper presents the results of an analysis of indicators that can be used to predict whether a student will succeed in a Computer Science Ph.D. program. The analysis was conducted by studying the records of 75 students who have been in the Computer Science Ph.D. program of the University of Alabama in Huntsville. Seventy-seven variables were…
Computer program for predicting creep behavior of bodies of revolution
NASA Technical Reports Server (NTRS)
Adams, R.; Greenbaum, G.
1971-01-01
Computer program, CRAB, uses finite-element method to calculate creep behavior and predict steady-state stresses in an arbitrary body of revolution subjected to a time-dependent axisymmetric load. Creep strains follow a time hardening law and a Prandtl-Reuss stress-strain relationship.
Users' manual for the Langley high speed propeller noise prediction program (DFP-ATP)
NASA Technical Reports Server (NTRS)
Dunn, M. H.; Tarkenton, G. M.
1989-01-01
The use of the Dunn-Farassat-Padula Advanced Technology Propeller (DFP-ATP) noise prediction program which computes the periodic acoustic pressure signature and spectrum generated by propellers moving with supersonic helical tip speeds is described. The program has the capacity of predicting noise produced by a single-rotation propeller (SRP) or a counter-rotation propeller (CRP) system with steady or unsteady blade loading. The computational method is based on two theoretical formulations developed by Farassat. One formulation is appropriate for subsonic sources, and the other for transonic or supersonic sources. Detailed descriptions of user input, program output, and two test cases are presented, as well as brief discussions of the theoretical formulations and computational algorithms employed.
A computer program for predicting nonlinear uniaxial material responses using viscoplastic models
NASA Technical Reports Server (NTRS)
Chang, T. Y.; Thompson, R. L.
1984-01-01
A computer program was developed for predicting nonlinear uniaxial material responses using viscoplastic constitutive models. Four specific models, i.e., those due to Miller, Walker, Krieg-Swearengen-Rhode, and Robinson, are included. Any other unified model is easily implemented into the program in the form of subroutines. Analysis features include stress-strain cycling, creep response, stress relaxation, thermomechanical fatigue loop, or any combination of these responses. An outline is given on the theoretical background of uniaxial constitutive models, analysis procedure, and numerical integration methods for solving the nonlinear constitutive equations. In addition, a discussion on the computer program implementation is also given. Finally, seven numerical examples are included to demonstrate the versatility of the computer program developed.
Computer programs to predict induced effects of jets exhausting into a crossflow
NASA Technical Reports Server (NTRS)
Perkins, S. C., Jr.; Mendenhall, M. R.
1984-01-01
A user's manual for two computer programs was developed to predict the induced effects of jets exhausting into a crossflow. Program JETPLT predicts pressures induced on an infinite flat plate by a jet exhausting at angles to the plate and Program JETBOD, in conjunction with a panel code, predicts pressures induced on a body of revolution by a jet exhausting normal to the surface. Both codes use a potential model of the jet and adjacent surface with empirical corrections for the viscous or nonpotential effects. This program manual contains a description of the use of both programs, instructions for preparation of input, descriptions of the output, limitations of the codes, and sample cases. In addition, procedures to extend both codes to include additional empirical correlations are described.
Study of high altitude plume impingement
NASA Technical Reports Server (NTRS)
Wojciechowski, C. J.; Penny, M. M.; Prozan, R. J.; Seymour, D.; Greenwood, T. F.
1972-01-01
Computer program has been developed as analytical tool to predict severity of effects of exhaust of rocket engines on adjacent spacecraft surfaces. Program computes forces, moments, pressures, and heating rates on surfaces immersed in or subjected to exhaust plume environments. Predictions will be useful in design of systems where such problems are anticipated.
DOT National Transportation Integrated Search
1975-12-01
Frequency domain computer programs developed or acquired by TSC for the analysis of rail vehicle dynamics are described in two volumes. Volume I defines the general analytical capabilities required for computer programs applicable to single rail vehi...
Performance predictions for an SSME configuration with an enlarged throat
NASA Technical Reports Server (NTRS)
Nickerson, G. R.; Dang, L. D.
1985-01-01
The Two Dimensional Kinetics (TDK) computer program that was recently developed for NASA was used to predict the performance of a Large Throat Configuration of the Space Shuttle Main Engine (SSME). Calculations indicate that the current design SSME contains a shock wave that is induced by the nozzle wall shape. In the Large Throat design an even stronger shock wave is predicted. Because of the presence of this shock wave, earlier performance predictions that have neglected shock wave effects have been questioned. The JANNAF thrust chamber performance prediction procedures given in a reference were applied. The analysis includes the effects of two dimensional reacting flow with a shock wave. The effects of the boundary layer with a regenatively cooled wall are also included. A Purdue computer program was used to compute axially symmetric supersonic nozzle flows with an induced shock, but is restricted to flows with a constant ratio of specific heats. Thus, the TDK program was also run with ths assumption and the results of the two programs were compared.
Characterization of the space shuttle reaction control system engine
NASA Technical Reports Server (NTRS)
Wilson, M. S.; Stechman, R. C.; Edelman, R. B.; Fortune, O. F.; Economos, C.
1972-01-01
A computer program was developed and written in FORTRAN 5 which predicts the transient and steady state performance and heat transfer characteristics of a pulsing GO2/GH2 rocket engine. This program predicts the dynamic flow and ignition characteristics which, when combined in a quasi-steady state manner with the combustion and mixing analysis program, will provide the thrust and specific impulse of the engine as a function of time. The program also predicts the transient and steady state heat transfer characteristics of the engine using various cooling concepts. The computer program, test case, and documentation are presented. The program is applicable to any system capable of utilizing the FORTRAN 4 or FORTRAN 5 language.
NASA Technical Reports Server (NTRS)
Chen, H. C.; Neback, H. E.; Kao, T. J.; Yu, N. Y.; Kusunose, K.
1991-01-01
This manual explains how to use an Euler based computational method for predicting the airframe/propulsion integration effects for an aft-mounted turboprop transport. The propeller power effects are simulated by the actuator disk concept. This method consists of global flow field analysis and the embedded flow solution for predicting the detailed flow characteristics in the local vicinity of an aft-mounted propfan engine. The computational procedure includes the use of several computer programs performing four main functions: grid generation, Euler solution, grid embedding, and streamline tracing. This user's guide provides information for these programs, including input data preparations with sample input decks, output descriptions, and sample Unix scripts for program execution in the UNICOS environment.
Aircraft noise prediction program propeller analysis system IBM-PC version user's manual version 2.0
NASA Technical Reports Server (NTRS)
Nolan, Sandra K.
1988-01-01
The IBM-PC version of the Aircraft Noise Prediction Program (ANOPP) Propeller Analysis System (PAS) is a set of computational programs for predicting the aerodynamics, performance, and noise of propellers. The ANOPP-PAS is a subset of a larger version of ANOPP which can be executed on CDC or VAX computers. This manual provides a description of the IBM-PC version of the ANOPP-PAS and its prediction capabilities, and instructions on how to use the system on an IBM-XT or IBM-AT personal computer. Sections within the manual document installation, system design, ANOPP-PAS usage, data entry preprocessors, and ANOPP-PAS functional modules and procedures. Appendices to the manual include a glossary of ANOPP terms and information on error diagnostics and recovery techniques.
An analysis of the 70-meter antenna hydrostatic bearing by means of computer simulation
NASA Technical Reports Server (NTRS)
Bartos, R. D.
1993-01-01
Recently, the computer program 'A Computer Solution for Hydrostatic Bearings with Variable Film Thickness,' used to design the hydrostatic bearing of the 70-meter antennas, was modified to improve the accuracy with which the program predicts the film height profile and oil pressure distribution between the hydrostatic bearing pad and the runner. This article presents a description of the modified computer program, the theory upon which the computer program computations are based, computer simulation results, and a discussion of the computer simulation results.
Basis And Application Of The CARES/LIFE Computer Program
NASA Technical Reports Server (NTRS)
Nemeth, Noel N.; Janosik, Lesley A.; Gyekenyesi, John P.; Powers, Lynn M.
1996-01-01
Report discusses physical and mathematical basis of Ceramics Analysis and Reliability Evaluation of Structures LIFE prediction (CARES/LIFE) computer program, described in "Program for Evaluation of Reliability of Ceramic Parts" (LEW-16018).
Acoustic environmental accuracy requirements for response determination
NASA Technical Reports Server (NTRS)
Pettitt, M. R.
1983-01-01
A general purpose computer program was developed for the prediction of vehicle interior noise. This program, named VIN, has both modal and statistical energy analysis capabilities for structural/acoustic interaction analysis. The analytic models and their computer implementation were verified through simple test cases with well-defined experimental results. The model was also applied in a space shuttle payload bay launch acoustics prediction study. The computer program processes large and small problems with equal efficiency because all arrays are dynamically sized by program input variables at run time. A data base is built and easily accessed for design studies. The data base significantly reduces the computational costs of such studies by allowing the reuse of the still-valid calculated parameters of previous iterations.
NASA Technical Reports Server (NTRS)
Tibbetts, J. G.
1980-01-01
Detailed instructions for using the near field cruise noise prediction program, a program listing, and a sample case with output are presented. The total noise for free field lossless conditions at selected observer locations is obtained by summing the contributions from up to nine acoustic sources. These noise sources, selected at the user's option, include the fan/compressor, turbine, core (combustion), jet, shock, and airframe (trailing edge and turbulent boundary layers). The effects of acoustic suppression materials such as engine inlet treatment may also be included in the noise prediction. The program is available for use on the NASA/Langley Research Center CDC computer. Comparisons of the program predictions with measured data are also given, and some possible reasons for their lack of agreement presented.
NASA Technical Reports Server (NTRS)
Holms, A. G.
1982-01-01
A previous report described a backward deletion procedure of model selection that was optimized for minimum prediction error and which used a multiparameter combination of the F - distribution and an order statistics distribution of Cochran's. A computer program is described that applies the previously optimized procedure to real data. The use of the program is illustrated by examples.
Dyadic Instruction for Middle School Students: Liking Promotes Learning
Hartl, Amy C.; DeLay, Dawn; Laursen, Brett; Denner, Jill; Werner, Linda; Campe, Shannon; Ortiz, Eloy
2015-01-01
This study examines whether friendship facilitates or hinders learning in a dyadic instructional setting. Working in 80 same-sex pairs, 160 (60 girls, 100 boys) middle school students (M = 12.13 years old) were taught a new computer programming language and programmed a game. Students spent 14 to 30 (M = 22.7) hours in a programming class. At the beginning and the end of the project, each participant separately completed (a) computer programming knowledge assessments and (b) questionnaires rating their affinity for their partner. Results support the proposition that liking promotes learning: Greater partner affinity predicted greater subsequent increases in computer programming knowledge for both partners. One partner’s initial programming knowledge also positively predicted the other partner’s subsequent partner affinity. PMID:26688658
Study Of Flow About A Helicopter Rotor
NASA Technical Reports Server (NTRS)
Tauber, Michael E.; Owen, F. Kevin
1989-01-01
Noninvasive instrument verifies computer program predicting velocities. Laser velocimeter measurements confirm predictions of transonic flow field around tip of helicopter-rotor blade. Report discusses measurements, which yield high-resolution orthogonal velocity components of flow field at rotor-tip. Mach numbers from 0.85 to 0.95, and use of measurements in verifying ability of computer program ROT22 to predict transonic flow field, including occurrences, strengths, and locations of shock waves causing high drag and noise.
The Road to Computer Literacy. Part V: Objectives and Activities for Grades 10-12.
ERIC Educational Resources Information Center
Bitter, Gary
1983-01-01
Presents computer-oriented activities in computer awareness and programing for students in grades 10-12. Intended for use by teachers of all disciplines, activities include such topics as prediction, interpretation and generalization of data, computer systems, PASCAL and PILOT programing, sampling techniques, computer survival, invasion of…
NASA Technical Reports Server (NTRS)
Brentner, K. S.
1986-01-01
A computer program has been developed at the Langley Research Center to predict the discrete frequency noise of conventional and advanced helicopter rotors. The program, called WOPWOP, uses the most advanced subsonic formulation of Farassat that is less sensitive to errors and is valid for nearly all helicopter rotor geometries and flight conditions. A brief derivation of the acoustic formulation is presented along with a discussion of the numerical implementation of the formulation. The computer program uses realistic helicopter blade motion and aerodynamic loadings, input by the user, for noise calculation in the time domain. A detailed definition of all the input variables, default values, and output data is included. A comparison with experimental data shows good agreement between prediction and experiment; however, accurate aerodynamic loading is needed.
Computer program user's manual for advanced general aviation propeller study
NASA Technical Reports Server (NTRS)
Worobel, R.
1972-01-01
A user's manual is presented for a computer program for predicting the performance (static, flight, and reverse), noise, weight and cost of propellers for advanced general aviation aircraft of the 1980 time period. Complete listings of this computer program with detailed instructions and samples of input and output are included.
Analysis of rocket engine injection combustion processes
NASA Technical Reports Server (NTRS)
Salmon, J. W.; Saltzman, D. H.
1977-01-01
Mixing methodology improvement for the JANNAF DER and CICM injection/combustion analysis computer programs was accomplished. ZOM plane prediction model development was improved for installation into the new standardized DER computer program. An intra-element mixing model developing approach was recommended for gas/liquid coaxial injection elements for possible future incorporation into the CICM computer program.
DOT National Transportation Integrated Search
1975-12-01
Frequency domain computer programs developed or acquired by TSC for the analysis of rail vehicle dynamics are described in two volumes. Volume 2 contains program listings including subroutines for the four TSC frequency domain programs described in V...
Jet engine noise source and noise footprint computer programs
NASA Technical Reports Server (NTRS)
Dunn, D. G.; Peart, N. A.; Miller, D. L.; Crowley, K. C.
1972-01-01
Calculation procedures are presented for predicting maximum passby noise levels and contours (footprints) of conventional jet aircraft with or without noise suppression devices. The procedures have been computerized and a user's guide is presented for the computer programs to be used in predicting the noise characteristics during aircraft takeoffs, fly-over, and/or landing operations.
Computer-aided roll pass design in rolling of airfoil shapes
NASA Technical Reports Server (NTRS)
Akgerman, N.; Lahoti, G. D.; Altan, T.
1980-01-01
This paper describes two computer-aided design (CAD) programs developed for modeling the shape rolling process for airfoil sections. The first program, SHPROL, uses a modular upper-bound method of analysis and predicts the lateral spread, elongation, and roll torque. The second program, ROLPAS, predicts the stresses, roll separating force, the roll torque and the details of metal flow by simulating the rolling process, using the slab method of analysis. ROLPAS is an interactive program; it offers graphic display capabilities and allows the user to interact with the computer via a keyboard, CRT, and a light pen. The accuracy of the computerized models was evaluated by (a) rolling a selected airfoil shape at room temperature from 1018 steel and isothermally at high temperature from Ti-6Al-4V, and (b) comparing the experimental results with computer predictions. The comparisons indicated that the CAD systems, described here, are useful for practical engineering purposes and can be utilized in roll pass design and analysis for airfoil and similar shapes.
Statistical energy analysis computer program, user's guide
NASA Technical Reports Server (NTRS)
Trudell, R. W.; Yano, L. I.
1981-01-01
A high frequency random vibration analysis, (statistical energy analysis (SEA) method) is examined. The SEA method accomplishes high frequency prediction of arbitrary structural configurations. A general SEA computer program is described. A summary of SEA theory, example problems of SEA program application, and complete program listing are presented.
VAPEPS user's reference manual, version 5.0
NASA Technical Reports Server (NTRS)
Park, D. M.
1988-01-01
This is the reference manual for the VibroAcoustic Payload Environment Prediction System (VAPEPS). The system consists of a computer program and a vibroacoustic database. The purpose of the system is to collect measurements of vibroacoustic data taken from flight events and ground tests, and to retrieve this data and provide a means of using the data to predict future payload environments. This manual describes the operating language of the program. Topics covered include database commands, Statistical Energy Analysis (SEA) prediction commands, stress prediction command, and general computational commands.
Program For Joule-Thomson Analysis Of Mixed Cryogens
NASA Technical Reports Server (NTRS)
Jones, Jack A.; Lund, Alan
1994-01-01
JTMIX computer program predicts ideal and realistic properties of mixed gases at temperatures between 65 and 80 K. Performs Joule-Thomson analysis of any gaseous mixture of neon, nitrogen, various hydrocarbons, argon, oxygen, carbon monoxide, carbon dioxide, and hydrogen sulfide. When used in conjunction with DDMIX computer program of National Institute of Standards and Technology (NIST), JTMIX accurately predicts order-of-magnitude increases in Joule-Thomson cooling capacities occuring when various hydrocarbons added to nitrogen. Also predicts boiling temperature of nitrogen depressed from normal value to as low as 60 K upon addition of neon. Written in Turbo C.
Shuttle environmental and thermal control/life support system computer program, supplement 1
NASA Technical Reports Server (NTRS)
Ayotte, W. J.
1975-01-01
The computer programs developed to simulate the RSECS (Representative Shuttle Environmental Control System) were described. These programs were prepared to provide pretest predictions, post-test analysis and real time problem analysis for RSECS test planning and evaluation.
Unsteady flow model for circulation-control airfoils
NASA Technical Reports Server (NTRS)
Rao, B. M.
1979-01-01
An analysis and a numerical lifting surface method are developed for predicting the unsteady airloads on two-dimensional circulation control airfoils in incompressible flow. The analysis and the computer program are validated by correlating the computed unsteady airloads with test data and also with other theoretical solutions. Additionally, a mathematical model for predicting the bending-torsion flutter of a two-dimensional airfoil (a reference section of a wing or rotor blade) and a computer program using an iterative scheme are developed. The flutter program has a provision for using the CC airfoil airloads program or the Theodorsen hard flap solution to compute the unsteady lift and moment used in the flutter equations. The adopted mathematical model and the iterative scheme are used to perform a flutter analysis of a typical CC rotor blade reference section. The program seems to work well within the basic assumption of the incompressible flow.
Computer program to predict noise of general aviation aircraft: User's guide
NASA Technical Reports Server (NTRS)
Mitchell, J. A.; Barton, C. K.; Kisner, L. S.; Lyon, C. A.
1982-01-01
Program NOISE predicts General Aviation Aircraft far-field noise levels at FAA FAR Part 36 certification conditions. It will also predict near-field and cabin noise levels for turboprop aircraft and static engine component far-field noise levels.
NASA Technical Reports Server (NTRS)
Jones, J. E.; Richmond, J. H.
1974-01-01
An integral equation formulation is applied to predict pitch- and roll-plane radiation patterns of a thin VHF/UHF (very high frequency/ultra high frequency) annular slot communications antenna operating at several locations in the nose region of the space shuttle orbiter. Digital computer programs used to compute radiation patterns are given and the use of the programs is illustrated. Experimental verification of computed patterns is given from measurements made on 1/35-scale models of the orbiter.
Prediction of overall and blade-element performance for axial-flow pump configurations
NASA Technical Reports Server (NTRS)
Serovy, G. K.; Kavanagh, P.; Okiishi, T. H.; Miller, M. J.
1973-01-01
A method and a digital computer program for prediction of the distributions of fluid velocity and properties in axial flow pump configurations are described and evaluated. The method uses the blade-element flow model and an iterative numerical solution of the radial equilbrium and continuity conditions. Correlated experimental results are used to generate alternative methods for estimating blade-element turning and loss characteristics. Detailed descriptions of the computer program are included, with example input and typical computed results.
Practical application of computer programs for supersonic combustion
NASA Technical Reports Server (NTRS)
Groves, F. R., Jr.
1972-01-01
Experimental data were interpreted using two supersonic combustion computer programs. The P1 program is based on a conventional boundary layer treatment of the mixing of concentric gas streams and complete combustion chemistry. The H1 program is based on a modified boundary layer approach which accounts for radial pressure gradients in the flow and also incorporates a finite rate chemistry calculation. The objective of the investigation was to compare the experimental data with theoretical predictions of the two programs with special emphasis on the prediction of radial pressure gradients by the H1 program. A test of the H1 program was also desired through comparison with the experimental data and with the P1 program.
DEVELOPING COMPUTATIONAL TOOLS FOR PREDICTING CHEMICAL FATE, METABOLISM, AND TOXICITY PATHWAYS
ORD's research program in Computational Toxicology (CompTox) will enable EPA Program Offices and other regulators to prioritize and reduce toxicity-testing requirements for potentially hazardous chemicals. The CompTox program defines the "toxicity process" as follows : 1) a stre...
Microbial burden prediction model for unmanned planetary spacecraft
NASA Technical Reports Server (NTRS)
Hoffman, A. R.; Winterburn, D. A.
1972-01-01
The technical development of a computer program for predicting microbial burden on unmanned planetary spacecraft is outlined. The discussion includes the derivation of the basic analytical equations, the selection of a method for handling several random variables, the macrologic of the computer programs and the validation and verification of the model. The prediction model was developed to (1) supplement the biological assays of a spacecraft by simulating the microbial accretion during periods when assays are not taken; (2) minimize the necessity for a large number of microbiological assays; and (3) predict the microbial loading on a lander immediately prior to sterilization and other non-lander equipment prior to launch. It is shown that these purposes not only were achieved but also that the prediction results compare favorably to the estimates derived from the direct assays. The computer program can be applied not only as a prediction instrument but also as a management and control tool. The basic logic of the model is shown to have possible applicability to other sequential flow processes, such as food processing.
Program Predicts Time Courses of Human/Computer Interactions
NASA Technical Reports Server (NTRS)
Vera, Alonso; Howes, Andrew
2005-01-01
CPM X is a computer program that predicts sequences of, and amounts of time taken by, routine actions performed by a skilled person performing a task. Unlike programs that simulate the interaction of the person with the task environment, CPM X predicts the time course of events as consequences of encoded constraints on human behavior. The constraints determine which cognitive and environmental processes can occur simultaneously and which have sequential dependencies. The input to CPM X comprises (1) a description of a task and strategy in a hierarchical description language and (2) a description of architectural constraints in the form of rules governing interactions of fundamental cognitive, perceptual, and motor operations. The output of CPM X is a Program Evaluation Review Technique (PERT) chart that presents a schedule of predicted cognitive, motor, and perceptual operators interacting with a task environment. The CPM X program allows direct, a priori prediction of skilled user performance on complex human-machine systems, providing a way to assess critical interfaces before they are deployed in mission contexts.
Loblolly Pine Growth and Yield Prediction for Managed West Gulf Plantations
V. Clark Baldwin; D.P. Feduccia
1987-01-01
Complete description, including tables, graphs, computer output, of a growth and yield prediction system providing volume and weight yields in stand and stock table format. An example of system use is given along with information about the computer program, COMPUTE P-LOB, that operates the system.
NASA Technical Reports Server (NTRS)
1987-01-01
Philip Morris research center scientists use a computer program called CECTRP, for Chemical Equilibrium Composition and Transport Properties, to gain insight into the behavior of atoms as they progress along the reaction pathway. Use of the program lets the scientist accurately predict the behavior of a given molecule or group of molecules. Computer generated data must be checked by laboratory experiment, but the use of CECTRP saves the researchers hundreds of hours of laboratory time since experiments must run only to validate the computer's prediction. Philip Morris estimates that had CECTRP not been available, at least two man years would have been required to develop a program to perform similar free energy calculations.
Structural behavior of composites with progressive fracture
NASA Technical Reports Server (NTRS)
Minnetyan, L.; Murthy, P. L. N.; Chamis, C. C.
1989-01-01
The objective of the study is to unify several computational tools developed for the prediction of progressive damage and fracture with efforts for the prediction of the overall response of damaged composite structures. In particular, a computational finite element model for the damaged structure is developed using a computer program as a byproduct of the analysis of progressive damage and fracture. Thus, a single computational investigation can predict progressive fracture and the resulting variation in structural properties of angleplied composites.
The Shock and Vibration Digest. Volume 14, Number 11
1982-11-01
cooled reactor 1981) ( HTGR ) core under seismic excitation his been developed . N82-18644 The computer program can be used to predict the behavior (In...French) of the HTGR core under seismic excitation. Key Words: Computer programs , Modal analysis, Beams, Undamped structures A computation method is...30) PROGRAMMING c c Dale and Cohen [221 extended the method of McMunn and Plunkett [201 developed a compute- McMunn and Plunkett to continuous systems
NASA Technical Reports Server (NTRS)
Arya, Vinod K.; Halford, Gary R. (Technical Monitor)
2003-01-01
This manual presents computer programs FLAPS for characterizing and predicting fatigue and creep-fatigue resistance of metallic materials in the high-temperature, long-life regime for isothermal and nonisothermal fatigue. The programs use the Total Strain version of Strainrange Partitioning (TS-SRP), and several other life prediction methods described in this manual. The user should be thoroughly familiar with the TS-SRP and these life prediction methods before attempting to use any of these programs. Improper understanding can lead to incorrect use of the method and erroneous life predictions. An extensive database has also been developed in a parallel effort. The database is probably the largest source of high-temperature, creep-fatigue test data available in the public domain and can be used with other life-prediction methods as well. This users' manual, software, and database are all in the public domain and can be obtained by contacting the author. The Compact Disk (CD) accompanying this manual contains an executable file for the FLAPS program, two datasets required for the example problems in the manual, and the creep-fatigue data in a format compatible with these programs.
Sun Series program for the REEDA System. [predicting orbital lifetime using sunspot values
NASA Technical Reports Server (NTRS)
Shankle, R. W.
1980-01-01
Modifications made to data bases and to four programs in a series of computer programs (Sun Series) which run on the REEDA HP minicomputer system to aid NASA's solar activity predictions used in orbital life time predictions are described. These programs utilize various mathematical smoothing technique and perform statistical and graphical analysis of various solar activity data bases residing on the REEDA System.
User's guide to the NOZL3D and NOZLIC computer programs
NASA Technical Reports Server (NTRS)
Thomas, P. D.
1980-01-01
Complete FORTRAN listings and running instructions are given for a set of computer programs that perform an implicit numerical solution to the unsteady Navier-Stokes equations to predict the flow characteristics and performance of nonaxisymmetric nozzles. The set includes the NOZL3D program, which performs the flow computations; the NOZLIC program, which sets up the flow field initial conditions for general nozzle configurations, and also generates the computational grid for simple two dimensional and axisymmetric configurations; and the RGRIDD program, which generates the computational grid for complicated three dimensional configurations. The programs are designed specifically for the NASA-Langley CYBER 175 computer, and employ auxiliary disk files for primary data storage. Input instructions and computed results are given for four test cases that include two dimensional, three dimensional, and axisymmetric configurations.
A transient performance method for CO2 removal with regenerable adsorbents
NASA Technical Reports Server (NTRS)
Hwang, K. C.
1972-01-01
A computer program is described which can be used to predict the transient performance of vacuum-desorbed sorbent beds for CO2 or water removal, and composite beds of two sorbents for simultaneous humidity control and CO2 removal. The program was written primarily for silica gel and molecular sieve inorganic sorbents, but can be used for a variety of adsorbent materials. Part 2 of this report describes a computer program which can be used to predict performance for multiple-bed CO2-removal sorbent systems. This program is an expanded version of the composite sorbent bed program described in Part 1.
EPAs National Center for Computational Toxicology is developing methods that apply computational chemistry, high-throughput screening (HTS) and genomic technologies to predict potential toxicity and prioritize the use of limited testing resources.
NASA Technical Reports Server (NTRS)
Simmons, D. B.
1975-01-01
The DOMONIC system has been modified to run on the Univac 1108 and the CDC 6600 as well as the IBM 370 computer system. The DOMONIC monitor system has been implemented to gather data which can be used to optimize the DOMONIC system and to predict the reliability of software developed using DOMONIC. The areas of quality metrics, error characterization, program complexity, program testing, validation and verification are analyzed. A software reliability model for estimating program completion levels and one on which to base system acceptance have been developed. The DAVE system which performs flow analysis and error detection has been converted from the University of Colorado CDC 6400/6600 computer to the IBM 360/370 computer system for use with the DOMONIC system.
The Coastal Ocean Prediction Systems program: Understanding and managing our coastal ocean
DOE Office of Scientific and Technical Information (OSTI.GOV)
Eden, H.F.; Mooers, C.N.K.
1990-06-01
The goal of COPS is to couple a program of regular observations to numerical models, through techniques of data assimilation, in order to provide a predictive capability for the US coastal ocean including the Great Lakes, estuaries, and the entire Exclusive Economic Zone (EEZ). The objectives of the program include: determining the predictability of the coastal ocean and the processes that govern the predictability; developing efficient prediction systems for the coastal ocean based on the assimilation of real-time observations into numerical models; and coupling the predictive systems for the physical behavior of the coastal ocean to predictive systems for biological,more » chemical, and geological processes to achieve an interdisciplinary capability. COPS will provide the basis for effective monitoring and prediction of coastal ocean conditions by optimizing the use of increased scientific understanding, improved observations, advanced computer models, and computer graphics to make the best possible estimates of sea level, currents, temperatures, salinities, and other properties of entire coastal regions.« less
Atmospheric transmission computer program CP
NASA Technical Reports Server (NTRS)
Pitts, D. E.; Barnett, T. L.; Korb, C. L.; Hanby, W.; Dillinger, A. E.
1974-01-01
A computer program is described which allows for calculation of the effects of carbon dioxide, water vapor, methane, ozone, carbon monoxide, and nitrous oxide on earth resources remote sensing techniques. A flow chart of the program and operating instructions are provided. Comparisons are made between the atmospheric transmission obtained from laboratory and spacecraft spectrometer data and that obtained from a computer prediction using a model atmosphere and radiosonde data. Limitations of the model atmosphere are discussed. The computer program listings, input card formats, and sample runs for both radiosonde data and laboratory data are included.
PREVAPORATION PERFORMANCE PREDICTION SOFTWARE
The Pervaporation, Performance, Prediction Software and Database (PPPS&D) computer software program is currently being developed within the USEPA, NRMRL. The purpose of the PPPS&D program is to educate and assist potential users in identifying opportunities for using pervaporati...
Comparisons of AEROX computer program predictions of lift and induced drag with flight test data
NASA Technical Reports Server (NTRS)
Axelson, J.; Hill, G. C.
1981-01-01
The AEROX aerodynamic computer program which provides accurate predictions of induced drag and trim drag for the full angle of attack range and for Mach numbers from 0.4 to 3.0 is described. This capability is demonstrated comparing flight test data and AEROX predictions for 17 different tactical aircraft. Values of minimum (skin friction, pressure, and zero lift wave) drag coefficients and lift coefficient offset due to camber (when required) were input from the flight test data to produce total lift and drag curves. The comparisons of trimmed lift drag polars show excellent agreement between the AEROX predictions and the in flight measurements.
NASA Technical Reports Server (NTRS)
Ferguson, D. R.
1972-01-01
The streamtube curvature program (STC) has been developed to predict the inviscid flow field and the pressure distribution about nacelles at transonic speeds. The effects of boundary layer are to displace the inviscid flow and effectively change the body shape. Thus, the body shape must be corrected by the displacement thickness in order to calculate the correct pressure distribution. This report describes the coupling of the Stratford and Beavers boundary layer solution with the inviscid STC analysis so that all nacelle pressure forces, friction drag, and incipient separation may be predicted. The usage of the coupled STC-SAB computer program is outlined and the program input and output are defined. Included in this manual are descriptions of the principal boundary layer tables and other revisions to the STC program. The use of the viscous option is controlled by the engineer during program input definition.
Predictive Software Cost Model Study. Volume I. Final Technical Report.
1980-06-01
development phase to identify computer resources necessary to support computer programs after transfer of program manangement responsibility and system... classical model development with refinements specifically applicable to avionics systems. The refinements are the result of the Phase I literature search
NASA Technical Reports Server (NTRS)
Pao, J. L.; Mehrotra, S. C.; Lan, C. E.
1982-01-01
A computer code base on an improved vortex filament/vortex core method for predicting aerodynamic characteristics of slender wings with edge vortex separations is developed. The code is applicable to camber wings, straked wings or wings with leading edge vortex flaps at subsonic speeds. The prediction of lifting pressure distribution and the computer time are improved by using a pair of concentrated vortex cores above the wing surface. The main features of this computer program are: (1) arbitrary camber shape may be defined and an option for exactly defining leading edge flap geometry is also provided; (2) the side edge vortex system is incorporated.
Spherical roller bearing analysis. SKF computer program SPHERBEAN. Volume 2: User's manual
NASA Technical Reports Server (NTRS)
Kleckner, R. J.; Dyba, G. J.
1980-01-01
The user's guide for the SPHERBEAN computer program for prediction of the thermomechanical performance characteristics of high speed lubricated double row spherical roller bearings is presented. The material presented is structured to guide the user in the practical and correct implementation of SPHERBEAN. Input and output, guidelines for program use, and sample executions are detailed.
NASA Astrophysics Data System (ADS)
Vermeer, M.
1981-07-01
A program was designed to replace AIMLASER for the generation of aiming predictions, to achieve a major saving in computing time, and to keep the program small enough for use even on small systems. An approach was adopted that incorporated the numerical integration of the orbit through a pass, limiting the computation of osculating elements to only one point per pass. The numerical integration method which is fourth order in delta t in the cumulative error after a given time lapse is presented. Algorithms are explained and a flowchart and listing of the program are provided.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Klopman, G.; Tu, M.
1997-09-01
It is shown that a combination of two programs, MultiCASE and META, can help assess the biodegradability of industrial organic materials in the ecosystem. MultiCASE is an artificial intelligence computer program that had been trained to identify molecular substructures believed to cause or inhibit biodegradation and META is an expert system trained to predict the aerobic biodegradation products of organic molecules. These two programs can be used to help evaluate the fate of disposed chemicals by estimating their biodegradability and the nature of their biodegradation products under conditions that may model the environment.
Myers, E W; Mount, D W
1986-01-01
We describe a program which may be used to find approximate matches to a short predefined DNA sequence in a larger target DNA sequence. The program predicts the usefulness of specific DNA probes and sequencing primers and finds nearly identical sequences that might represent the same regulatory signal. The program is written in the C programming language and will run on virtually any computer system with a C compiler, such as the IBM/PC and other computers running under the MS/DOS and UNIX operating systems. The program has been integrated into an existing software package for the IBM personal computer (see article by Mount and Conrad, this volume). Some examples of its use are given. PMID:3753785
Alford, Rebecca F.; Dolan, Erin L.
2017-01-01
Computational biology is an interdisciplinary field, and many computational biology research projects involve distributed teams of scientists. To accomplish their work, these teams must overcome both disciplinary and geographic barriers. Introducing new training paradigms is one way to facilitate research progress in computational biology. Here, we describe a new undergraduate program in biomolecular structure prediction and design in which students conduct research at labs located at geographically-distributed institutions while remaining connected through an online community. This 10-week summer program begins with one week of training on computational biology methods development, transitions to eight weeks of research, and culminates in one week at the Rosetta annual conference. To date, two cohorts of students have participated, tackling research topics including vaccine design, enzyme design, protein-based materials, glycoprotein modeling, crowd-sourced science, RNA processing, hydrogen bond networks, and amyloid formation. Students in the program report outcomes comparable to students who participate in similar in-person programs. These outcomes include the development of a sense of community and increases in their scientific self-efficacy, scientific identity, and science values, all predictors of continuing in a science research career. Furthermore, the program attracted students from diverse backgrounds, which demonstrates the potential of this approach to broaden the participation of young scientists from backgrounds traditionally underrepresented in computational biology. PMID:29216185
Alford, Rebecca F; Leaver-Fay, Andrew; Gonzales, Lynda; Dolan, Erin L; Gray, Jeffrey J
2017-12-01
Computational biology is an interdisciplinary field, and many computational biology research projects involve distributed teams of scientists. To accomplish their work, these teams must overcome both disciplinary and geographic barriers. Introducing new training paradigms is one way to facilitate research progress in computational biology. Here, we describe a new undergraduate program in biomolecular structure prediction and design in which students conduct research at labs located at geographically-distributed institutions while remaining connected through an online community. This 10-week summer program begins with one week of training on computational biology methods development, transitions to eight weeks of research, and culminates in one week at the Rosetta annual conference. To date, two cohorts of students have participated, tackling research topics including vaccine design, enzyme design, protein-based materials, glycoprotein modeling, crowd-sourced science, RNA processing, hydrogen bond networks, and amyloid formation. Students in the program report outcomes comparable to students who participate in similar in-person programs. These outcomes include the development of a sense of community and increases in their scientific self-efficacy, scientific identity, and science values, all predictors of continuing in a science research career. Furthermore, the program attracted students from diverse backgrounds, which demonstrates the potential of this approach to broaden the participation of young scientists from backgrounds traditionally underrepresented in computational biology.
Turbofan forced mixer-nozzle internal flowfield. Volume 2: Computational fluid dynamic predictions
NASA Technical Reports Server (NTRS)
Werle, M. J.; Vasta, V. N.
1982-01-01
A general program was conducted to develop and assess a computational method for predicting the flow properties in a turbofan forced mixed duct. The detail assessment of the resulting computer code is presented. It was found that the code provided excellent predictions of the kinematics of the mixing process throughout the entire length of the mixer nozzle. The thermal mixing process between the hot core and cold fan flows was found to be well represented in the low speed portion of the flowfield.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Hameka, H.F.; Jensen, J.O.
1993-05-01
This report presents the computed optimized geometry and vibrational IR and Raman frequencies of the V-agent VX. The computations are performed with the Gaussian 90 Program Package using 6-31G* basis sets. We assign the vibrational frequencies and correct each frequency by multiplying it with a previously derived 6-31G* correction factor. The result is a computer-generated prediction of the IR and Raman spectra of VX. This study was intended as a blind test of the utility of IR spectral prediction. Therefore, we intentionally did not look at experimental data on the IR and Raman spectra of VX.... IR Spectra, VX, Ramanmore » spectra, Computer predictions.« less
Feasibility of MHD submarine propulsion
DOE Office of Scientific and Technical Information (OSTI.GOV)
Doss, E.D.; Sikes, W.C.
1992-09-01
This report describes the work performed during Phase 1 and Phase 2 of the collaborative research program established between Argonne National Laboratory (ANL) and Newport News Shipbuilding and Dry Dock Company (NNS). Phase I of the program focused on the development of computer models for Magnetohydrodynamic (MHD) propulsion. Phase 2 focused on the experimental validation of the thruster performance models and the identification, through testing, of any phenomena which may impact the attractiveness of this propulsion system for shipboard applications. The report discusses in detail the work performed in Phase 2 of the program. In Phase 2, a two Teslamore » test facility was designed, built, and operated. The facility test loop, its components, and their design are presented. The test matrix and its rationale are discussed. Representative experimental results of the test program are presented, and are compared to computer model predictions. In general, the results of the tests and their comparison with the predictions indicate that thephenomena affecting the performance of MHD seawater thrusters are well understood and can be accurately predicted with the developed thruster computer models.« less
The U.S. Environmental Protection Agency (EPA) Computational Toxicology Program develops and utilizes QSAR modeling approaches across a broad range of applications. In terms of physical chemistry we have a particular interest in the prediction of basic physicochemical parameters ...
DOT National Transportation Integrated Search
2001-02-01
A new version of the CRCP computer program, CRCP-9, has been developed in this study. The numerical model of the CRC pavements was developed using finite element theories, the crack spacing prediction model was developed using the Monte Carlo method,...
COMPUTER PROGRAM FOR THE NRL SATELLITE POSITION DISPLAY,
NRL Satellite position Prediction And Display ( SPAD ), provides a considerable amount of display control versatility. Up to eleven satellites can be...expanded mode. A commercial equivalent of the AN/UYK-1 computer was used in the research version of SPAD . Since the program was written in a
NASA Technical Reports Server (NTRS)
Smith, Tamara A.; Pavli, Albert J.; Kacynski, Kenneth J.
1987-01-01
The Joint Army, Navy, NASA, Air Force (JANNAF) rocket-engine performance-prediction procedure is based on the use of various reference computer programs. One of the reference programs for nozzle analysis is the Two-Dimensional Kinetics (TDK) Program. The purpose of this report is to calibrate the JANNAF procedure that has been incorporated into the December 1984 version of the TDK program for the high-area-ratio rocket-engine regime. The calibration was accomplished by modeling the performance of a 1030:1 rocket nozzle tested at NASA Lewis. A detailed description of the test conditions and TDK input parameters is given. The reuslts indicate that the computer code predicts delivered vacuum specific impulse to within 0.12 to 1.9 percent of the experimental data. Vacuum thrust coefficient predictions were within + or - 1.3 percent of experimental results. Predictions of wall static pressure were within approximately + or - 5 percent of the measured values.
An Improved Version of the NASA-Lockheed Multielement Airfoil Analysis Computer Program
NASA Technical Reports Server (NTRS)
Brune, G. W.; Manke, J. W.
1978-01-01
An improved version of the NASA-Lockheed computer program for the analysis of multielement airfoils is described. The predictions of the program are evaluated by comparison with recent experimental high lift data including lift, pitching moment, profile drag, and detailed distributions of surface pressures and boundary layer parameters. The results of the evaluation show that the contract objectives of improving program reliability and accuracy have been met.
NASA Technical Reports Server (NTRS)
Morin, Bruce L.
2010-01-01
Pratt & Whitney has developed a Broadband Fan Noise Prediction System (BFaNS) for turbofan engines. This system computes the noise generated by turbulence impinging on the leading edges of the fan and fan exit guide vane, and noise generated by boundary-layer turbulence passing over the fan trailing edge. BFaNS has been validated on three fan rigs that were tested during the NASA Advanced Subsonic Technology Program (AST). The predicted noise spectra agreed well with measured data. The predicted effects of fan speed, vane count, and vane sweep also agreed well with measurements. The noise prediction system consists of two computer programs: Setup_BFaNS and BFaNS. Setup_BFaNS converts user-specified geometry and flow-field information into a BFaNS input file. From this input file, BFaNS computes the inlet and aft broadband sound power spectra generated by the fan and FEGV. The output file from BFaNS contains the inlet, aft and total sound power spectra from each noise source. This report is the second volume of a three-volume set documenting the Broadband Fan Noise Prediction System: Volume 1: Setup_BFaNS User s Manual and Developer s Guide; Volume 2: BFaNS User s Manual and Developer s Guide; and Volume 3: Validation and Test Cases. The present volume begins with an overview of the Broadband Fan Noise Prediction System, followed by step-by-step instructions for installing and running BFaNS. It concludes with technical documentation of the BFaNS computer program.
NASA Technical Reports Server (NTRS)
Morin, Bruce L.
2010-01-01
Pratt & Whitney has developed a Broadband Fan Noise Prediction System (BFaNS) for turbofan engines. This system computes the noise generated by turbulence impinging on the leading edges of the fan and fan exit guide vane, and noise generated by boundary-layer turbulence passing over the fan trailing edge. BFaNS has been validated on three fan rigs that were tested during the NASA Advanced Subsonic Technology Program (AST). The predicted noise spectra agreed well with measured data. The predicted effects of fan speed, vane count, and vane sweep also agreed well with measurements. The noise prediction system consists of two computer programs: Setup_BFaNS and BFaNS. Setup_BFaNS converts user-specified geometry and flow-field information into a BFaNS input file. From this input file, BFaNS computes the inlet and aft broadband sound power spectra generated by the fan and FEGV. The output file from BFaNS contains the inlet, aft and total sound power spectra from each noise source. This report is the first volume of a three-volume set documenting the Broadband Fan Noise Prediction System: Volume 1: Setup_BFaNS User s Manual and Developer s Guide; Volume 2: BFaNS User's Manual and Developer s Guide; and Volume 3: Validation and Test Cases. The present volume begins with an overview of the Broadband Fan Noise Prediction System, followed by step-by-step instructions for installing and running Setup_BFaNS. It concludes with technical documentation of the Setup_BFaNS computer program.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Sowell, E.
1979-06-01
The Building Loads Analysis and System Thermodynamics (BLAST) program is a comprehensive set of subprograms for predicting energy consumption in buildings. There are three major subprograms: (1) the space load predicting subprogram, which computes hourly space loads in a building or zone based on user input and hourly weather data; (2) the air distribution system simulation subprogram, which uses the computed space load and user inputs describing the building air-handling system to calculate hot water or steam, chilled water, and electric energy demands; and (3) the central plant simulation program, which simulates boilers, chillers, onsite power generating equipment and solarmore » energy systems and computes monthly and annual fuel and electrical power consumption and plant life cycle cost.« less
NASA Technical Reports Server (NTRS)
Plankey, B.
1981-01-01
A computer program called ECPVER (Energy Consumption Program - Verification) was developed to simulate all energy loads for any number of buildings. The program computes simulated daily, monthly, and yearly energy consumption which can be compared with actual meter readings for the same time period. Such comparison can lead to validation of the model under a variety of conditions, which allows it to be used to predict future energy saving due to energy conservation measures. Predicted energy saving can then be compared with actual saving to verify the effectiveness of those energy conservation changes. This verification procedure is planned to be an important advancement in the Deep Space Network Energy Project, which seeks to reduce energy cost and consumption at all DSN Deep Space Stations.
Computational prediction of chemical reactions: current status and outlook.
Engkvist, Ola; Norrby, Per-Ola; Selmi, Nidhal; Lam, Yu-Hong; Peng, Zhengwei; Sherer, Edward C; Amberg, Willi; Erhard, Thomas; Smyth, Lynette A
2018-06-01
Over the past few decades, various computational methods have become increasingly important for discovering and developing novel drugs. Computational prediction of chemical reactions is a key part of an efficient drug discovery process. In this review, we discuss important parts of this field, with a focus on utilizing reaction data to build predictive models, the existing programs for synthesis prediction, and usage of quantum mechanics and molecular mechanics (QM/MM) to explore chemical reactions. We also outline potential future developments with an emphasis on pre-competitive collaboration opportunities. Copyright © 2018 Elsevier Ltd. All rights reserved.
A Computer Program for Preliminary Data Analysis
Dennis L. Schweitzer
1967-01-01
ABSTRACT. -- A computer program written in FORTRAN has been designed to summarize data. Class frequencies, means, and standard deviations are printed for as many as 100 independent variables. Cross-classifications of an observed dependent variable and of a dependent variable predicted by a multiple regression equation can also be generated.
NASA Technical Reports Server (NTRS)
Masters, P. A.
1974-01-01
An analysis to predict the pressurant gas requirements for the discharge of cryogenic liquid propellants from storage tanks is presented, along with an algorithm and two computer programs. One program deals with the pressurization (ramp) phase of bringing the propellant tank up to its operating pressure. The method of analysis involves a numerical solution of the temperature and velocity functions for the tank ullage at a discrete set of points in time and space. The input requirements of the program are the initial ullage conditions, the initial temperature and pressure of the pressurant gas, and the time for the expulsion or the ramp. Computations are performed which determine the heat transfer between the ullage gas and the tank wall. Heat transfer to the liquid interface and to the hardware components may be included in the analysis. The program output includes predictions of mass of pressurant required, total energy transfer, and wall and ullage temperatures. The analysis, the algorithm, a complete description of input and output, and the FORTRAN 4 program listings are presented. Sample cases are included to illustrate use of the programs.
High Speed Research Noise Prediction Code (HSRNOISE) User's and Theoretical Manual
NASA Technical Reports Server (NTRS)
Golub, Robert (Technical Monitor); Rawls, John W., Jr.; Yeager, Jessie C.
2004-01-01
This report describes a computer program, HSRNOISE, that predicts noise levels for a supersonic aircraft powered by mixed flow turbofan engines with rectangular mixer-ejector nozzles. It fully documents the noise prediction algorithms, provides instructions for executing the HSRNOISE code, and provides predicted noise levels for the High Speed Research (HSR) program Technology Concept (TC) aircraft. The component source noise prediction algorithms were developed jointly by Boeing, General Electric Aircraft Engines (GEAE), NASA and Pratt & Whitney during the course of the NASA HSR program. Modern Technologies Corporation developed an alternative mixer ejector jet noise prediction method under contract to GEAE that has also been incorporated into the HSRNOISE prediction code. Algorithms for determining propagation effects and calculating noise metrics were taken from the NASA Aircraft Noise Prediction Program.
Aircraft noise prediction program validation
NASA Technical Reports Server (NTRS)
Shivashankara, B. N.
1980-01-01
A modular computer program (ANOPP) for predicting aircraft flyover and sideline noise was developed. A high quality flyover noise data base for aircraft that are representative of the U.S. commercial fleet was assembled. The accuracy of ANOPP with respect to the data base was determined. The data for source and propagation effects were analyzed and suggestions for improvements to the prediction methodology are given.
Secondary Structure Predictions for Long RNA Sequences Based on Inversion Excursions and MapReduce.
Yehdego, Daniel T; Zhang, Boyu; Kodimala, Vikram K R; Johnson, Kyle L; Taufer, Michela; Leung, Ming-Ying
2013-05-01
Secondary structures of ribonucleic acid (RNA) molecules play important roles in many biological processes including gene expression and regulation. Experimental observations and computing limitations suggest that we can approach the secondary structure prediction problem for long RNA sequences by segmenting them into shorter chunks, predicting the secondary structures of each chunk individually using existing prediction programs, and then assembling the results to give the structure of the original sequence. The selection of cutting points is a crucial component of the segmenting step. Noting that stem-loops and pseudoknots always contain an inversion, i.e., a stretch of nucleotides followed closely by its inverse complementary sequence, we developed two cutting methods for segmenting long RNA sequences based on inversion excursions: the centered and optimized method. Each step of searching for inversions, chunking, and predictions can be performed in parallel. In this paper we use a MapReduce framework, i.e., Hadoop, to extensively explore meaningful inversion stem lengths and gap sizes for the segmentation and identify correlations between chunking methods and prediction accuracy. We show that for a set of long RNA sequences in the RFAM database, whose secondary structures are known to contain pseudoknots, our approach predicts secondary structures more accurately than methods that do not segment the sequence, when the latter predictions are possible computationally. We also show that, as sequences exceed certain lengths, some programs cannot computationally predict pseudoknots while our chunking methods can. Overall, our predicted structures still retain the accuracy level of the original prediction programs when compared with known experimental secondary structure.
[Development of a predictive program for microbial growth under various temperature conditions].
Fujikawa, Hiroshi; Yano, Kazuyoshi; Morozumi, Satoshi; Kimura, Bon; Fujii, Tateo
2006-12-01
A predictive program for microbial growth under various temperature conditions was developed with a mathematical model. The model was a new logistic model recently developed by us. The program predicts Escherichia coli growth in broth, Staphylococcus aureus growth and its enterotoxin production in milk, and Vibrio parahaemolyticus growth in broth at various temperature patterns. The program, which was built with Microsoft Excel (Visual Basic Application), is user-friendly; users can easily input the temperature history of a test food and obtain the prediction instantly on the computer screen. The predicted growth and toxin production can be important indices to determine whether a food is microbiologically safe or not. This program should be a useful tool to confirm the microbial safety of commercial foods.
ERIC Educational Resources Information Center
Cheema, Jehanzeb R.; Zhang, Bo
2013-01-01
This study looked at the effect of both quantity and quality of computer use on achievement. The Program for International Student Assessment (PISA) 2003 student survey comprising of 4,356 students (boys, n = 2,129; girls, n = 2,227) was used to predict academic achievement from quantity and quality of computer use while controlling for…
Computer-aided injection molding system
NASA Astrophysics Data System (ADS)
Wang, K. K.; Shen, S. F.; Cohen, C.; Hieber, C. A.; Isayev, A. I.
1982-10-01
Achievements are reported in cavity-filling simulation, modeling viscoelastic effects, measuring and predicting frozen-in birefringence in molded parts, measuring residual stresses and associated mechanical properties of molded parts, and developing an interactive mold-assembly design program and an automatic NC maching data generation and verification program. The Cornell Injection Molding Program (CIMP) consortium is discussed as are computer user manuals that have been published by the consortium. Major tasks which should be addressed in future efforts are listed, including: (1) predict and experimentally determine the post-fillin behavior of thermoplastics; (2) simulate and experimentally investigate the injection molding of thermosets and filled materials; and (3) further investigate residual stresses, orientation and mechanical properties.
Introduction to Computational Methods for Stability and Control (COMSAC)
NASA Technical Reports Server (NTRS)
Hall, Robert M.; Fremaux, C. Michael; Chambers, Joseph R.
2004-01-01
This Symposium is intended to bring together the often distinct cultures of the Stability and Control (S&C) community and the Computational Fluid Dynamics (CFD) community. The COMSAC program is itself a new effort by NASA Langley to accelerate the application of high end CFD methodologies to the demanding job of predicting stability and control characteristics of aircraft. This talk is intended to set the stage for needing a program like COMSAC. It is not intended to give details of the program itself. The topics include: 1) S&C Challenges; 2) Aero prediction methodology; 3) CFD applications; 4) NASA COMSAC planning; 5) Objectives of symposium; and 6) Closing remarks.
Pocket computers: a new aid to nutritional support.
Colley, C M; Fleck, A; Howard, J P
1985-01-01
A program has been written to run on a pocket computer (Sharp PC-1500) that can be used at the bedside to predict the nutritional requirements of patients with a wide range of clinical conditions. The predictions of the program showed good correlation with measured values for energy and nitrogen requirements. The program was used, with good results, in the management of over 100 patients needing nutritional support. The calculation of nutritional requirements for each patient individually facilitates more appropriate treatment and may also produce financial savings when compared with administration of a standard feeding regimen to all patients. Images FIG 1 PMID:3922512
1977-02-11
Continue an reverse aide If necessaty and Identify by block number) A comprehensive computational procedure is presented for predicting the...Aeroballistic Reentry Technology ( ART ) program with some of the fundamental analytical and numerical work supported by NSWC Independent Research Funds. Most of...the Aerospace Corporation. The authors gratefully acknowledge the efforts of Mr. R. Feldhuhn, NSWC coordinator for the ART program, who was responsible
Computational techniques for solar wind flows past terrestrial planets: Theory and computer programs
NASA Technical Reports Server (NTRS)
Stahara, S. S.; Chaussee, D. S.; Trudinger, B. C.; Spreiter, J. R.
1977-01-01
The interaction of the solar wind with terrestrial planets can be predicted using a computer program based on a single fluid, steady, dissipationless, magnetohydrodynamic model to calculate the axisymmetric, supersonic, super-Alfvenic solar wind flow past both magnetic and nonmagnetic planets. The actual calculations are implemented by an assemblage of computer codes organized into one program. These include finite difference codes which determine the gas-dynamic solution, together with a variety of special purpose output codes for determining and automatically plotting both flow field and magnetic field results. Comparisons are made with previous results, and results are presented for a number of solar wind flows. The computational programs developed are documented and are presented in a general user's manual which is included.
Predicting Noise From Wind Turbines
NASA Technical Reports Server (NTRS)
Grosveld, Ferdinand W.
1990-01-01
Computer program WINDY predicts broadband noise spectra of horizontal-axis wind-turbine generators. Enables adequate assessment of impact of broadband wind-turbine noise. Effects of turbulence, trailing-edge wakes, and bluntness taken into account. Program has practical application in design and siting of wind-turbine machines acceptable to community. Written in GW-Basic.
NASA Technical Reports Server (NTRS)
Saltsman, James F.
1992-01-01
This manual presents computer programs for characterizing and predicting fatigue and creep-fatigue resistance of metallic materials in the high-temperature, long-life regime for isothermal and nonisothermal fatigue. The programs use the total strain version of Strainrange Partitioning (TS-SRP). An extensive database has also been developed in a parallel effort. This database is probably the largest source of high-temperature, creep-fatigue test data available in the public domain and can be used with other life prediction methods as well. This users manual, software, and database are all in the public domain and are available through COSMIC (382 East Broad Street, Athens, GA 30602; (404) 542-3265, FAX (404) 542-4807). Two disks accompany this manual. The first disk contains the source code, executable files, and sample output from these programs. The second disk contains the creep-fatigue data in a format compatible with these programs.
Extreme Scale Computing to Secure the Nation
DOE Office of Scientific and Technical Information (OSTI.GOV)
Brown, D L; McGraw, J R; Johnson, J R
2009-11-10
Since the dawn of modern electronic computing in the mid 1940's, U.S. national security programs have been dominant users of every new generation of high-performance computer. Indeed, the first general-purpose electronic computer, ENIAC (the Electronic Numerical Integrator and Computer), was used to calculate the expected explosive yield of early thermonuclear weapons designs. Even the U. S. numerical weather prediction program, another early application for high-performance computing, was initially funded jointly by sponsors that included the U.S. Air Force and Navy, agencies interested in accurate weather predictions to support U.S. military operations. For the decades of the cold war, national securitymore » requirements continued to drive the development of high performance computing (HPC), including advancement of the computing hardware and development of sophisticated simulation codes to support weapons and military aircraft design, numerical weather prediction as well as data-intensive applications such as cryptography and cybersecurity U.S. national security concerns continue to drive the development of high-performance computers and software in the U.S. and in fact, events following the end of the cold war have driven an increase in the growth rate of computer performance at the high-end of the market. This mainly derives from our nation's observance of a moratorium on underground nuclear testing beginning in 1992, followed by our voluntary adherence to the Comprehensive Test Ban Treaty (CTBT) beginning in 1995. The CTBT prohibits further underground nuclear tests, which in the past had been a key component of the nation's science-based program for assuring the reliability, performance and safety of U.S. nuclear weapons. In response to this change, the U.S. Department of Energy (DOE) initiated the Science-Based Stockpile Stewardship (SBSS) program in response to the Fiscal Year 1994 National Defense Authorization Act, which requires, 'in the absence of nuclear testing, a progam to: (1) Support a focused, multifaceted program to increase the understanding of the enduring stockpile; (2) Predict, detect, and evaluate potential problems of the aging of the stockpile; (3) Refurbish and re-manufacture weapons and components, as required; and (4) Maintain the science and engineering institutions needed to support the nation's nuclear deterrent, now and in the future'. This program continues to fulfill its national security mission by adding significant new capabilities for producing scientific results through large-scale computational simulation coupled with careful experimentation, including sub-critical nuclear experiments permitted under the CTBT. To develop the computational science and the computational horsepower needed to support its mission, SBSS initiated the Accelerated Strategic Computing Initiative, later renamed the Advanced Simulation & Computing (ASC) program (sidebar: 'History of ASC Computing Program Computing Capability'). The modern 3D computational simulation capability of the ASC program supports the assessment and certification of the current nuclear stockpile through calibration with past underground test (UGT) data. While an impressive accomplishment, continued evolution of national security mission requirements will demand computing resources at a significantly greater scale than we have today. In particular, continued observance and potential Senate confirmation of the Comprehensive Test Ban Treaty (CTBT) together with the U.S administration's promise for a significant reduction in the size of the stockpile and the inexorable aging and consequent refurbishment of the stockpile all demand increasing refinement of our computational simulation capabilities. Assessment of the present and future stockpile with increased confidence of the safety and reliability without reliance upon calibration with past or future test data is a long-term goal of the ASC program. This will be accomplished through significant increases in the scientific bases that underlie the computational tools. Computer codes must be developed that replace phenomenology with increased levels of scientific understanding together with an accompanying quantification of uncertainty. These advanced codes will place significantly higher demands on the computing infrastructure than do the current 3D ASC codes. This article discusses not only the need for a future computing capability at the exascale for the SBSS program, but also considers high performance computing requirements for broader national security questions. For example, the increasing concern over potential nuclear terrorist threats demands a capability to assess threats and potential disablement technologies as well as a rapid forensic capability for determining a nuclear weapons design from post-detonation evidence (nuclear counterterrorism).« less
Use of the Computer for Research on Instruction and Student Understanding in Physics.
NASA Astrophysics Data System (ADS)
Grayson, Diane Jeanette
This dissertation describes an investigation of how the computer may be utilized to perform research on instruction and on student understanding in physics. The research was conducted within three content areas: kinematics, waves and dynamics. The main focus of the research on instruction was the determination of factors needed for a computer program to be instructionally effective. The emphasis in the research on student understanding was the identification of specific conceptual and reasoning difficulties students encounter with the subject matter. Most of the research was conducted using the computer -based interview, a technique developed during the early part of the work, conducted within the domain of kinematics. In a computer-based interview, a student makes a prediction about how a particular system will behave under given circumstances, observes a simulation of the event on a computer screen, and then is asked by an interviewer to explain any discrepancy between prediction and observation. In the course of the research, a model was developed for producing educational software. The model has three important components: (i) research on student difficulties in the content area to be addressed, (ii) observations of students using the computer program, and (iii) consequent program modification. This model was used to guide the development of an instructional computer program dealing with graphical representations of transverse pulses. Another facet of the research involved the design of a computer program explicitly for the purposes of research. A computer program was written that simulates a modified Atwood's machine. The program was than used in computer -based interviews and proved to be an effective means of probing student understanding of dynamics concepts. In order to ascertain whether or not the student difficulties identified were peculiar to the computer, laboratory-based interviews with real equipment were also conducted. The laboratory-based interviews were designed to parallel the computer-based interviews as closely as possible. The results of both types of interviews are discussed in detail. The dissertation concludes with a discussion of some of the benefits of using the computer in physics instruction and physics education research. Attention is also drawn to some of the limitations of the computer as a research instrument or instructional device.
Computations of soot and and NO sub x emissions from gas turbine combustors
NASA Technical Reports Server (NTRS)
Srivatsa, S. K.
1982-01-01
An analytical program was conducted to compute the soot and NOx emissions from a combustor and the radiation heat transfer to the combustor walls. The program involved the formulation of an emission and radiation model and the incorporation of this model into the Garrett 3-D Combustor Perfomance Computer Program. Computations were performed for the idle, cruise, and take-off conditions of a JT8D can combustor. The predicted soot and NOx emissions and the radiation heat transfer to the combustor walls agree reasonably well with the limited experimental data available.
NASA Technical Reports Server (NTRS)
Keith, J. S.; Ferguson, D. R.; Heck, P. H.
1973-01-01
The computer program listing of Streamtube Curvature Analysis is presented. The listing includes explanatory statements and titles so that the program flow is readily discernable. The computer program listing is in CDC FORTRAN 2.3 source language form, except for three subroutines, GETIX, GETRLX, and SAVIX, which are in COMPOSE 1.1 language.
Computerized optimization of radioimmunoassays for hCG and estradiol: an experimental evaluation
DOE Office of Scientific and Technical Information (OSTI.GOV)
Yanagishita, M.; Rodbard, D.
1978-07-15
The mathematical and statistical theory of radioimmunoassays (RIAs) has been used to develop a series of computer programs to optimize sensitivity or precision at any desired dose level for either equilibrium or nonequilibrium assays. These computer programs provide for the calculation of the equilibrium constants of association and binding capacities for antisera (parameters of Scatchard plots), the association and dissociation rate constants, and prediction of optimum concentration of labeled ligand and antibody and optimum incubation times for the assay. This paper presents an experimental evaluation of the use of these computer programs applied to RIAs for human chorionic gonadotropin (hCG)more » and estradiol. The experimental results are in reasonable semiquantitative agreement with the predictions of the computer simulations (usually within a factor of two) and thus partially validate the use of computer techniques to optimize RIAs that are reasonably well behaved, as in the case of the hCG and estradiol RIAs. Further, these programs can provide insights into the nature of the RIA system, e.g., the general nature of the sensitivity and precision surfaces. This facilitates empirical optimization of conditions.« less
Advanced Simulation and Computing Fiscal Year 14 Implementation Plan, Rev. 0.5
DOE Office of Scientific and Technical Information (OSTI.GOV)
Meisner, Robert; McCoy, Michel; Archer, Bill
2013-09-11
The Stockpile Stewardship Program (SSP) is a single, highly integrated technical program for maintaining the surety and reliability of the U.S. nuclear stockpile. The SSP uses nuclear test data, computational modeling and simulation, and experimental facilities to advance understanding of nuclear weapons. It includes stockpile surveillance, experimental research, development and engineering programs, and an appropriately scaled production capability to support stockpile requirements. This integrated national program requires the continued use of experimental facilities and programs, and the computational enhancements to support these programs. The Advanced Simulation and Computing Program (ASC) is a cornerstone of the SSP, providing simulation capabilities andmore » computational resources that support annual stockpile assessment and certification, study advanced nuclear weapons design and manufacturing processes, analyze accident scenarios and weapons aging, and provide the tools to enable stockpile Life Extension Programs (LEPs) and the resolution of Significant Finding Investigations (SFIs). This requires a balanced resource, including technical staff, hardware, simulation software, and computer science solutions. In its first decade, the ASC strategy focused on demonstrating simulation capabilities of unprecedented scale in three spatial dimensions. In its second decade, ASC is now focused on increasing predictive capabilities in a three-dimensional (3D) simulation environment while maintaining support to the SSP. The program continues to improve its unique tools for solving progressively more difficult stockpile problems (sufficient resolution, dimensionality, and scientific details), quantify critical margins and uncertainties, and resolve increasingly difficult analyses needed for the SSP. Moreover, ASC’s business model is integrated and focused on requirements-driven products that address long-standing technical questions related to enhanced predictive capability in the simulation tools.« less
Analysis of Satellite Communications Antenna Patterns
NASA Technical Reports Server (NTRS)
Rahmat-Samii, Y.
1985-01-01
Computer program accurately and efficiently predicts far-field patterns of offset, or symmetric, parabolic reflector antennas. Antenna designer uses program to study effects of varying geometrical and electrical (RF) parameters of parabolic reflector and its feed system. Accurate predictions of far-field patterns help designer predict overall performance of antenna. These reflectors used extensively in modern communications satellites and in multiple-beam and low side-lobe antenna systems.
NASA Technical Reports Server (NTRS)
Jumper, S. J.
1982-01-01
A computer program was developed to calculate the three dimensional, steady, incompressible, inviscid, irrotational flow field at the propeller plane (propeller removed) located upstream of an arbitrary airframe geometry. The program uses a horseshoe vortex of known strength to model the wing. All other airframe surfaces are modeled by a network source panels of unknown strength which is exposed to a uniform free stream and the wing-induced velocity field. By satisfying boundary conditions on each panel (the Neumann problem), relaxed boundary conditions being used on certain panels to simulate inlet inflow, the source strengths are determined. From the known source and wing vortex strengths, the resulting velocity fields on the airframe surface and at the propeller plane are obtained. All program equations are derived in detail, and a brief description of the program structure is presented. A user's manual which fully documents the program is cited. Computer predictions of the flow on the surface of a sphere and at a propeller plane upstream of the sphere are compared with the exact mathematical solutions. Agreement is good, and correct program operation is verified.
THREE-PEE SAMPLING THEORY and program 'THRP' for computer generation of selection criteria
L. R. Grosenbaugh
1965-01-01
Theory necessary for sampling with probability proportional to prediction ('three-pee,' or '3P,' sampling) is first developed and then exemplified by numerical comparisons of several estimators. Program 'T RP' for computer generation of appropriate 3P-sample-selection criteria is described, and convenient random integer dispensers are...
NASA Technical Reports Server (NTRS)
1978-01-01
The marine turbine pump pictured is the Jacuzzi 12YJ, a jet propulsion system for pleasure or commercial boating. Its development was aided by a NASA computer program made available by the Computer Software Management and Information Center (COSMIC) at the University of Georgia. The manufacturer, Jacuzzi Brothers, Incorporated, Little Rock, Arkansas, used COSMIC'S Computer Program for Predicting Turbopump Inducer Loading, which enabled substantial savings in development time and money through reduction of repetitive testing.
NASA Astrophysics Data System (ADS)
Simmons, B. E.
1981-08-01
This report derives equations predicting satellite ephemeris error as a function of measurement errors of space-surveillance sensors. These equations lend themselves to rapid computation with modest computer resources. They are applicable over prediction times such that measurement errors, rather than uncertainties of atmospheric drag and of Earth shape, dominate in producing ephemeris error. This report describes the specialization of these equations underlying the ANSER computer program, SEEM (Satellite Ephemeris Error Model). The intent is that this report be of utility to users of SEEM for interpretive purposes, and to computer programmers who may need a mathematical point of departure for limited generalization of SEEM.
Prediction of Scour below Flip Bucket using Soft Computing Techniques
NASA Astrophysics Data System (ADS)
Azamathulla, H. Md.; Ab Ghani, Aminuddin; Azazi Zakaria, Nor
2010-05-01
The accurate prediction of the depth of scour around hydraulic structure (trajectory spillways) has been based on the experimental studies and the equations developed are mainly empirical in nature. This paper evaluates the performance of the soft computing (intelligence) techiques, Adaptive Neuro-Fuzzy System (ANFIS) and Genetic expression Programming (GEP) approach, in prediction of scour below a flip bucket spillway. The results are very promising, which support the use of these intelligent techniques in prediction of highly non-linear scour parameters.
Computational scheme for the prediction of metal ion binding by a soil fulvic acid
Marinsky, J.A.; Reddy, M.M.; Ephraim, J.H.; Mathuthu, A.S.
1995-01-01
The dissociation and metal ion binding properties of a soil fulvic acid have been characterized. Information thus gained was used to compensate for salt and site heterogeneity effects in metal ion complexation by the fulvic acid. An earlier computational scheme has been modified by incorporating an additional step which improves the accuracy of metal ion speciation estimates. An algorithm is employed for the prediction of metal ion binding by organic acid constituents of natural waters (once the organic acid is characterized in terms of functional group identity and abundance). The approach discussed here, currently used with a spreadsheet program on a personal computer, is conceptually envisaged to be compatible with computer programs available for ion binding by inorganic ligands in natural waters.
Propeller aircraft interior noise model utilization study and validation
NASA Technical Reports Server (NTRS)
Pope, L. D.
1984-01-01
Utilization and validation of a computer program designed for aircraft interior noise prediction is considered. The program, entitled PAIN (an acronym for Propeller Aircraft Interior Noise), permits (in theory) predictions of sound levels inside propeller driven aircraft arising from sidewall transmission. The objective of the work reported was to determine the practicality of making predictions for various airplanes and the extent of the program's capabilities. The ultimate purpose was to discern the quality of predictions for tonal levels inside an aircraft occurring at the propeller blade passage frequency and its harmonics. The effort involved three tasks: (1) program validation through comparisons of predictions with scale-model test results; (2) development of utilization schemes for large (full scale) fuselages; and (3) validation through comparisons of predictions with measurements taken in flight tests on a turboprop aircraft. Findings should enable future users of the program to efficiently undertake and correctly interpret predictions.
A Summary of the Naval Postgraduate School Research Program and Recent Publications
1990-09-01
principles to divide the spectrum of MATLAB computer program on a 386-type a wide-band spread-spectrum signal into sub- computer. Because of the high rf...original in time and a large data sample was required. An signal. Effects due the fiber optic pickup array extended version of MATLAB that allows and...application, such as orbital mechanics and weather prediction. Professor Gragg has also developed numerous MATLAB programs for linear programming problems
Three-dimensional turbopump flowfield analysis
NASA Technical Reports Server (NTRS)
Sharma, O. P.; Belford, K. A.; Ni, R. H.
1992-01-01
A program was conducted to develop a flow prediction method applicable to rocket turbopumps. The complex nature of a flowfield in turbopumps is described and examples of flowfields are discussed to illustrate that physics based models and analytical calculation procedures based on computational fluid dynamics (CFD) are needed to develop reliable design procedures for turbopumps. A CFD code developed at NASA ARC was used as the base code. The turbulence model and boundary conditions in the base code were modified, respectively, to: (1) compute transitional flows and account for extra rates of strain, e.g., rotation; and (2) compute surface heat transfer coefficients and allow computation through multistage turbomachines. Benchmark quality data from two and three-dimensional cascades were used to verify the code. The predictive capabilities of the present CFD code were demonstrated by computing the flow through a radial impeller and a multistage axial flow turbine. Results of the program indicate that the present code operated in a two-dimensional mode is a cost effective alternative to full three-dimensional calculations, and that it permits realistic predictions of unsteady loadings and losses for multistage machines.
HIFiRE-1 Turbulent Shock Boundary Layer Interaction - Flight Data and Computations
NASA Technical Reports Server (NTRS)
Kimmel, Roger L.; Prabhu, Dinesh
2015-01-01
The Hypersonic International Flight Research Experimentation (HIFiRE) program is a hypersonic flight test program executed by the Air Force Research Laboratory (AFRL) and Australian Defence Science and Technology Organisation (DSTO). This flight contained a cylinder-flare induced shock boundary layer interaction (SBLI). Computations of the interaction were conducted for a number of times during the ascent. The DPLR code used for predictions was calibrated against ground test data prior to exercising the code at flight conditions. Generally, the computations predicted the upstream influence and interaction pressures very well. Plateau pressures on the cylinder were predicted well at all conditions. Although the experimental heat transfer showed a large amount of scatter, especially at low heating levels, the measured heat transfer agreed well with computations. The primary discrepancy between the experiment and computation occurred in the pressures measured on the flare during second stage burn. Measured pressures exhibited large overshoots late in the second stage burn, the mechanism of which is unknown. The good agreement between flight measurements and CFD helps validate the philosophy of calibrating CFD against ground test, prior to exercising it at flight conditions.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Doss, E.D.; Sikes, W.C.
1992-09-01
This report describes the work performed during Phase 1 and Phase 2 of the collaborative research program established between Argonne National Laboratory (ANL) and Newport News Shipbuilding and Dry Dock Company (NNS). Phase I of the program focused on the development of computer models for Magnetohydrodynamic (MHD) propulsion. Phase 2 focused on the experimental validation of the thruster performance models and the identification, through testing, of any phenomena which may impact the attractiveness of this propulsion system for shipboard applications. The report discusses in detail the work performed in Phase 2 of the program. In Phase 2, a two Teslamore » test facility was designed, built, and operated. The facility test loop, its components, and their design are presented. The test matrix and its rationale are discussed. Representative experimental results of the test program are presented, and are compared to computer model predictions. In general, the results of the tests and their comparison with the predictions indicate that thephenomena affecting the performance of MHD seawater thrusters are well understood and can be accurately predicted with the developed thruster computer models.« less
Predicting oligonucleotide affinity to nucleic acid targets.
Mathews, D H; Burkard, M E; Freier, S M; Wyatt, J R; Turner, D H
1999-01-01
A computer program, OligoWalk, is reported that predicts the equilibrium affinity of complementary DNA or RNA oligonucleotides to an RNA target. This program considers the predicted stability of the oligonucleotide-target helix and the competition with predicted secondary structure of both the target and the oligonucleotide. Both unimolecular and bimolecular oligonucleotide self structure are considered with a user-defined concentration. The application of OligoWalk is illustrated with three comparisons to experimental results drawn from the literature. PMID:10580474
Computation of transonic potential flow about 3 dimensional inlets, ducts, and bodies
NASA Technical Reports Server (NTRS)
Reyhner, T. A.
1982-01-01
An analysis was developed and a computer code, P465 Version A, written for the prediction of transonic potential flow about three dimensional objects including inlet, duct, and body geometries. Finite differences and line relaxation are used to solve the complete potential flow equation. The coordinate system used for the calculations is independent of body geometry. Cylindrical coordinates are used for the computer code. The analysis is programmed in extended FORTRAN 4 for the CYBER 203 vector computer. The programming of the analysis is oriented toward taking advantage of the vector processing capabilities of this computer. Comparisons of computed results with experimental measurements are presented to verify the analysis. Descriptions of program input and output formats are also presented.
Predicting the Coupling Properties of Axially-Textured Materials.
Fuentes-Cobas, Luis E; Muñoz-Romero, Alejandro; Montero-Cabrera, María E; Fuentes-Montero, Luis; Fuentes-Montero, María E
2013-10-30
A description of methods and computer programs for the prediction of "coupling properties" in axially-textured polycrystals is presented. Starting data are the single-crystal properties, texture and stereography. The validity and proper protocols for applying the Voigt, Reuss and Hill approximations to estimate coupling properties effective values is analyzed. Working algorithms for predicting mentioned averages are given. Bunge's symmetrized spherical harmonics expansion of orientation distribution functions, inverse pole figures and (single and polycrystals) physical properties is applied in all stages of the proposed methodology. The established mathematical route has been systematized in a working computer program. The discussion of piezoelectricity in a representative textured ferro-piezoelectric ceramic illustrates the application of the proposed methodology. Polycrystal coupling properties, predicted by the suggested route, are fairly close to experimentally measured ones.
Predicting the Coupling Properties of Axially-Textured Materials
Fuentes-Cobas, Luis E.; Muñoz-Romero, Alejandro; Montero-Cabrera, María E.; Fuentes-Montero, Luis; Fuentes-Montero, María E.
2013-01-01
A description of methods and computer programs for the prediction of “coupling properties” in axially-textured polycrystals is presented. Starting data are the single-crystal properties, texture and stereography. The validity and proper protocols for applying the Voigt, Reuss and Hill approximations to estimate coupling properties effective values is analyzed. Working algorithms for predicting mentioned averages are given. Bunge’s symmetrized spherical harmonics expansion of orientation distribution functions, inverse pole figures and (single and polycrystals) physical properties is applied in all stages of the proposed methodology. The established mathematical route has been systematized in a working computer program. The discussion of piezoelectricity in a representative textured ferro-piezoelectric ceramic illustrates the application of the proposed methodology. Polycrystal coupling properties, predicted by the suggested route, are fairly close to experimentally measured ones. PMID:28788370
Analysis of rocket engine injection combustion processes
NASA Technical Reports Server (NTRS)
Salmon, J. W.
1976-01-01
A critique is given of the JANNAF sub-critical propellant injection/combustion process analysis computer models and application of the models to correlation of well documented hot fire engine data bases. These programs are the distributed energy release (DER) model for conventional liquid propellants injectors and the coaxial injection combustion model (CICM) for gaseous annulus/liquid core coaxial injectors. The critique identifies model inconsistencies while the computer analyses provide quantitative data on predictive accuracy. The program is comprised of three tasks: (1) computer program review and operations; (2) analysis and data correlations; and (3) documentation.
Space shuttle propulsion parameter estimation using optional estimation techniques
NASA Technical Reports Server (NTRS)
1983-01-01
A regression analyses on tabular aerodynamic data provided. A representative aerodynamic model for coefficient estimation. It also reduced the storage requirements for the "normal' model used to check out the estimation algorithms. The results of the regression analyses are presented. The computer routines for the filter portion of the estimation algorithm and the :"bringing-up' of the SRB predictive program on the computer was developed. For the filter program, approximately 54 routines were developed. The routines were highly subsegmented to facilitate overlaying program segments within the partitioned storage space on the computer.
Three-dimensional vector modeling and restoration of flat finite wave tank radiometric measurements
NASA Technical Reports Server (NTRS)
Truman, W. M.; Balanis, C. A.
1977-01-01
The three-dimensional vector interaction between a microwave radiometer and a wave tank was modeled. Computer programs for predicting the response of the radiometer to the brightness temperature characteristics of the surroundings were developed along with a computer program that can invert (restore) the radiometer measurements. It is shown that the computer programs can be used to simulate the viewing of large bodies of water, and is applicable to radiometer measurements received from satellites monitoring the ocean. The water temperature, salinity, and wind speed can be determined.
Prediction of quantitative intrathoracic fluid volume to diagnose pulmonary oedema using LabVIEW.
Urooj, Shabana; Khan, M; Ansari, A Q; Lay-Ekuakille, Aimé; Salhan, Ashok K
2012-01-01
Pulmonary oedema is a life-threatening disease that requires special attention in the area of research and clinical diagnosis. Computer-based techniques are rarely used to quantify the intrathoracic fluid volume (IFV) for diagnostic purposes. This paper discusses a software program developed to detect and diagnose pulmonary oedema using LabVIEW. The software runs on anthropometric dimensions and physiological parameters, mainly transthoracic electrical impedance (TEI). This technique is accurate and faster than existing manual techniques. The LabVIEW software was used to compute the parameters required to quantify IFV. An equation relating per cent control and IFV was obtained. The results of predicted TEI and measured TEI were compared with previously reported data to validate the developed program. It was found that the predicted values of TEI obtained from the computer-based technique were much closer to the measured values of TEI. Six new subjects were enrolled to measure and predict transthoracic impedance and hence to quantify IFV. A similar difference was also observed in the measured and predicted values of TEI for the new subjects.
ACToR - Aggregated Computational Toxicology Resource ...
There are too many uncharacterized environmental chemicals to test with current in vivo protocols. Develop predictive in vitro screening assays that can be used to prioritize chemicals for detailed testing. ToxCast program requires large amounts of data: In vitro assays (mainly generated by ToxCast program) and In vivo data to develop and validate predictive signatures ACToR is compiling both sets of data for use in predictive algorithms.
Computer program documentation: Raw-to-processed SINDA program (RTOPHS) user's guide
NASA Technical Reports Server (NTRS)
Damico, S. J.
1980-01-01
Use of the Raw to Processed SINDA(System Improved Numerical Differencing Analyzer) Program, RTOPHS, which provides a means of making the temperature prediction data on binary HSTFLO and HISTRY units generated by SINDA available to engineers in an easy to use format, is discussed. The program accomplishes this by reading the HISTRY unit and according to user input instructions, the desired times and temperature prediction data are extracted and written to a word addressable drum file.
Engineering and programming manual: Two-dimensional kinetic reference computer program (TDK)
NASA Technical Reports Server (NTRS)
Nickerson, G. R.; Dang, L. D.; Coats, D. E.
1985-01-01
The Two Dimensional Kinetics (TDK) computer program is a primary tool in applying the JANNAF liquid rocket thrust chamber performance prediction methodology. The development of a methodology that includes all aspects of rocket engine performance from analytical calculation to test measurements, that is physically accurate and consistent, and that serves as an industry and government reference is presented. Recent interest in rocket engines that operate at high expansion ratio, such as most Orbit Transfer Vehicle (OTV) engine designs, has required an extension of the analytical methods used by the TDK computer program. Thus, the version of TDK that is described in this manual is in many respects different from the 1973 version of the program. This new material reflects the new capabilities of the TDK computer program, the most important of which are described.
BEHAVE: fire behavior prediction and fuel modeling system-BURN Subsystem, part 1
Patricia L. Andrews
1986-01-01
Describes BURN Subsystem, Part 1, the operational fire behavior prediction subsystem of the BEHAVE fire behavior prediction and fuel modeling system. The manual covers operation of the computer program, assumptions of the mathematical models used in the calculations, and application of the predictions.
Lampa, Samuel; Alvarsson, Jonathan; Spjuth, Ola
2016-01-01
Predictive modelling in drug discovery is challenging to automate as it often contains multiple analysis steps and might involve cross-validation and parameter tuning that create complex dependencies between tasks. With large-scale data or when using computationally demanding modelling methods, e-infrastructures such as high-performance or cloud computing are required, adding to the existing challenges of fault-tolerant automation. Workflow management systems can aid in many of these challenges, but the currently available systems are lacking in the functionality needed to enable agile and flexible predictive modelling. We here present an approach inspired by elements of the flow-based programming paradigm, implemented as an extension of the Luigi system which we name SciLuigi. We also discuss the experiences from using the approach when modelling a large set of biochemical interactions using a shared computer cluster.Graphical abstract.
Computer program to perform cost and weight analysis of transport aircraft. Volume 1: Summary
NASA Technical Reports Server (NTRS)
1973-01-01
A digital computer program for evaluating the weight and costs of advanced transport designs was developed. The resultant program, intended for use at the preliminary design level, incorporates both batch mode and interactive graphics run capability. The basis of the weight and cost estimation method developed is a unique way of predicting the physical design of each detail part of a vehicle structure at a time when only configuration concept drawings are available. In addition, the technique relies on methods to predict the precise manufacturing processes and the associated material required to produce each detail part. Weight data are generated in four areas of the program. Overall vehicle system weights are derived on a statistical basis as part of the vehicle sizing process. Theoretical weights, actual weights, and the weight of the raw material to be purchased are derived as part of the structural synthesis and part definition processes based on the computed part geometry.
CROMAX : a crosscut-first computer simulation program to determine cutting yield
Pamela J. Giese; Jeanne D. Danielson
1983-01-01
CROMAX simulates crosscut-first, then rip operations as commonly practiced in furniture manufacture. This program calculates cutting yields from individual boards based on board size and defect location. Such information can be useful in predicting yield from various grades and grade mixes thereby allowing for better management decisions in the rough mill. The computer...
A new computer program for mass screening of visual defects in preschool children.
Briscoe, D; Lifshitz, T; Grotman, M; Kushelevsky, A; Vardi, H; Weizman, S; Biedner, B
1998-04-01
To test the effectiveness of a PC computer program for detecting vision disorders which could be used by non-trained personnel, and to determine the prevalence of visual impairment in a sample population of preschool children in the city of Beer-Sheba, Israel. 292 preschool children, aged 4-6 years, were examined in the kindergarten setting, using the computer system and "gold standard" tests. Visual acuity and stereopsis were tested and compared using Snellen type symbol charts and random dot stereograms respectively. The sensitivity, specificity, positive predictive value, negative predictive value, and kappa test were evaluated. A computer pseudo Worth four dot test was also performed but could not be compared with the standard Worth four dot test owing to the inability of many children to count. Agreement between computer and gold standard tests was 83% and 97.3% for visual acuity and stereopsis respectively. The sensitivity of the computer stereogram was only 50%, but it had a specificity of 98.9%, whereas the sensitivity and specificity of the visual acuity test were 81.5% and 83% respectively. The positive predictive value of both tests was about 63%. 27.7% of children tested had a visual acuity of 6/12 or less and stereopsis was absent in 28% using standard tests. Impairment of fusion was found in 5% of children using the computer pseudo Worth four dot test. The computer program was found to be stimulating, rapid, and easy to perform. The wide availability of computers in schools and at home allow it to be used as an additional screening tool by non-trained personnel, such as teachers and parents, but it is not a replacement for standard testing.
MPT Prediction of Aircraft-Engine Fan Noise
NASA Technical Reports Server (NTRS)
Connell, Stuart D.
2004-01-01
A collection of computer programs has been developed that implements a procedure for predicting multiple-pure-tone (MPT) noise generated by fan blades of an aircraft engine (e.g., a turbofan engine). MPT noise arises when the fan is operating with supersonic relative tip Mach No. Under this flow condition, there is a strong upstream running shock. The strength and position of this shock are very sensitive to blade geometry variations. For a fan where all the blades are identical, the primary tone observed upstream of the fan will be the blade passing frequency. If there are small variations in geometry between blades, then tones below the blade passing frequency arise MPTs. Stagger angle differences as small as 0.1 can give rise to significant MPT. It is also noted that MPT noise is more pronounced when the fan is operating in an unstarted mode. Computational results using a three-dimensional flow solver to compute the complete annulus flow with non-uniform fans indicate that MPT noise can be estimated in a relatively simple way. Hence, once the effect of a typical geometry variation of one blade in an otherwise uniform blade row is known, the effect of all the blades being different can be quickly computed via superposition. Two computer programs that were developed as part of this work are used in conjunction with a user s computational fluid dynamics (CFD) code to predict MPT spectra for a fan with a specified set of geometric variations: (1) The first program ROTBLD reads the users CFD solution files for a single blade passage via an API (Application Program Interface). There are options to replicate and perturb the geometry with typical variations stagger, camber, thickness, and pitch. The multi-passage CFD solution files are then written in the user s file format using the API. (2) The second program SUPERPOSE requires two input files: the first is the circumferential upstream pressure distribution extracted from the CFD solution on the multi-passage mesh, the second file defines the geometry variations of each blade in a complete fan. Superposition is used to predict the spectra resulting from the geometric variations.
NASA Technical Reports Server (NTRS)
Teske, M. E.
1984-01-01
This is a user manual for the computer code ""AGDISP'' (AGricultural DISPersal) which has been developed to predict the deposition of material released from fixed and rotary wing aircraft in a single-pass, computationally efficient manner. The formulation of the code is novel in that the mean particle trajectory and the variance about the mean resulting from turbulent fluid fluctuations are simultaneously predicted. The code presently includes the capability of assessing the influence of neutral atmospheric conditions, inviscid wake vortices, particle evaporation, plant canopy and terrain on the deposition pattern.
Use of the computer for research on student thinking in physics
NASA Astrophysics Data System (ADS)
Grayson, Diane J.; McDermott, Lillian C.
1996-05-01
This paper describes the use of the computer-based interview as a research technique for investigating how students think about physics. Two computer programs provide the context: one intended for instruction, the other for research. The one designed for use as an instructional aid displays the motion of a ball rolling along a track that has level and inclined segments. The associated motion graphs are also shown. The other program, which was expressly designed for use in research, is based on the simulated motion of a modified Atwood's machine. The programs require students to predict the effect of the initial conditions and system parameters on the motion or on a graph of the motion. The motion that would actually occur is then displayed. The investigation focuses on the reasoning used by the students as they try to resolve discrepancies between their predictions and observations.
Input guide for computer programs to generate thermodynamic data for air and Freon CF4
NASA Technical Reports Server (NTRS)
Tevepaugh, J. A.; Penny, M. M.; Baker, L. R., Jr.
1975-01-01
FORTRAN computer programs were developed to calculate the thermodynamic properties of Freon 14 and air for isentropic expansion from given plenum conditions. Thermodynamic properties for air are calculated with equations derived from the Beattie-Bridgeman nonstandard equation of state and, for Freon 14, with equations derived from the Redlich-Quang nonstandard equation of state. These two gases are used in scale model testing of model rocket nozzle flow fields which requires simulation of the prototype plume shape with a cold flow test approach. Utility of the computer programs for use in analytical prediction of flow fields is enhanced by arranging card or tape output of the data in a format compatible with a method-of-characteristics computer program.
FORTRAN program for predicting off-design performance of radial-inflow turbines
NASA Technical Reports Server (NTRS)
Wasserbauer, C. A.; Glassman, A. J.
1975-01-01
The FORTRAN IV program uses a one-dimensional solution of flow conditions through the turbine along the mean streamline. The program inputs needed are the design-point requirements and turbine geometry. The output includes performance and velocity-diagram parameters over a range of speed and pressure ratio. Computed performance is compared with the experimental data from two radial-inflow turbines and with the performance calculated by a previous computer program. The flow equations, program listing, and input and output for a sample problem are given.
Automated Performance Prediction of Message-Passing Parallel Programs
NASA Technical Reports Server (NTRS)
Block, Robert J.; Sarukkai, Sekhar; Mehra, Pankaj; Woodrow, Thomas S. (Technical Monitor)
1995-01-01
The increasing use of massively parallel supercomputers to solve large-scale scientific problems has generated a need for tools that can predict scalability trends of applications written for these machines. Much work has been done to create simple models that represent important characteristics of parallel programs, such as latency, network contention, and communication volume. But many of these methods still require substantial manual effort to represent an application in the model's format. The NIK toolkit described in this paper is the result of an on-going effort to automate the formation of analytic expressions of program execution time, with a minimum of programmer assistance. In this paper we demonstrate the feasibility of our approach, by extending previous work to detect and model communication patterns automatically, with and without overlapped computations. The predictions derived from these models agree, within reasonable limits, with execution times of programs measured on the Intel iPSC/860 and Paragon. Further, we demonstrate the use of MK in selecting optimal computational grain size and studying various scalability metrics.
Efficient pairwise RNA structure prediction using probabilistic alignment constraints in Dynalign
2007-01-01
Background Joint alignment and secondary structure prediction of two RNA sequences can significantly improve the accuracy of the structural predictions. Methods addressing this problem, however, are forced to employ constraints that reduce computation by restricting the alignments and/or structures (i.e. folds) that are permissible. In this paper, a new methodology is presented for the purpose of establishing alignment constraints based on nucleotide alignment and insertion posterior probabilities. Using a hidden Markov model, posterior probabilities of alignment and insertion are computed for all possible pairings of nucleotide positions from the two sequences. These alignment and insertion posterior probabilities are additively combined to obtain probabilities of co-incidence for nucleotide position pairs. A suitable alignment constraint is obtained by thresholding the co-incidence probabilities. The constraint is integrated with Dynalign, a free energy minimization algorithm for joint alignment and secondary structure prediction. The resulting method is benchmarked against the previous version of Dynalign and against other programs for pairwise RNA structure prediction. Results The proposed technique eliminates manual parameter selection in Dynalign and provides significant computational time savings in comparison to prior constraints in Dynalign while simultaneously providing a small improvement in the structural prediction accuracy. Savings are also realized in memory. In experiments over a 5S RNA dataset with average sequence length of approximately 120 nucleotides, the method reduces computation by a factor of 2. The method performs favorably in comparison to other programs for pairwise RNA structure prediction: yielding better accuracy, on average, and requiring significantly lesser computational resources. Conclusion Probabilistic analysis can be utilized in order to automate the determination of alignment constraints for pairwise RNA structure prediction methods in a principled fashion. These constraints can reduce the computational and memory requirements of these methods while maintaining or improving their accuracy of structural prediction. This extends the practical reach of these methods to longer length sequences. The revised Dynalign code is freely available for download. PMID:17445273
Beyond [lambda][subscript max] Part 2: Predicting Molecular Color
ERIC Educational Resources Information Center
Williams, Darren L.; Flaherty, Thomas J.; Alnasleh, Bassam K.
2009-01-01
A concise roadmap for using computational chemistry programs (i.e., Gaussian 03W) to predict the color of a molecular species is presented. A color-predicting spreadsheet is available with the online material that uses transition wavelengths and peak-shape parameters to predict the visible absorbance spectrum, transmittance spectrum, chromaticity…
Samarakoon, Pubudu Saneth; Sorte, Hanne Sørmo; Stray-Pedersen, Asbjørg; Rødningen, Olaug Kristin; Rognes, Torbjørn; Lyle, Robert
2016-01-14
With advances in next generation sequencing technology and analysis methods, single nucleotide variants (SNVs) and indels can be detected with high sensitivity and specificity in exome sequencing data. Recent studies have demonstrated the ability to detect disease-causing copy number variants (CNVs) in exome sequencing data. However, exonic CNV prediction programs have shown high false positive CNV counts, which is the major limiting factor for the applicability of these programs in clinical studies. We have developed a tool (cnvScan) to improve the clinical utility of computational CNV prediction in exome data. cnvScan can accept input from any CNV prediction program. cnvScan consists of two steps: CNV screening and CNV annotation. CNV screening evaluates CNV prediction using quality scores and refines this using an in-house CNV database, which greatly reduces the false positive rate. The annotation step provides functionally and clinically relevant information using multiple source datasets. We assessed the performance of cnvScan on CNV predictions from five different prediction programs using 64 exomes from Primary Immunodeficiency (PIDD) patients, and identified PIDD-causing CNVs in three individuals from two different families. In summary, cnvScan reduces the time and effort required to detect disease-causing CNVs by reducing the false positive count and providing annotation. This improves the clinical utility of CNV detection in exome data.
DOT National Transportation Integrated Search
1975-01-01
It was found that the coordinates of the highways required for Noise 1 could be supplied on punched cards by the Photogrammetry Section of the Department. In preparing data for contour plotting, it was found advisable to divide the area into sectors,...
Computer prediction of insecticide efficacy for western spruce budworm and Douglas-fir tussock moth
Jacqueline L. Robertson; Molly W. Stock
1986-01-01
A generalized interactive computer model that simulates and predicts insecticide efficacy, over seasonal development of western spruce budworm and Douglas-fir tussock moth, is described. This model can be used for any insecticide for which the user has laboratory-based concentration-response data. The program has four options, is written in BASIC, and can be operated...
ANOPP programmer's reference manual for the executive System. [aircraft noise prediction program
NASA Technical Reports Server (NTRS)
Gillian, R. E.; Brown, C. G.; Bartlett, R. W.; Baucom, P. H.
1977-01-01
Documentation for the Aircraft Noise Prediction Program as of release level 01/00/00 is presented in a manual designed for programmers having a need for understanding the internal design and logical concepts of the executive system software. Emphasis is placed on providing sufficient information to modify the system for enhancements or error correction. The ANOPP executive system includes software related to operating system interface, executive control, and data base management for the Aircraft Noise Prediction Program. It is written in Fortran IV for use on CDC Cyber series of computers.
Testing and Extending VSEPR with WebMO and MOPAC or GAMESS
ERIC Educational Resources Information Center
McNaught, Ian J.
2011-01-01
VSEPR is a topic that is commonly taught in undergraduate chemistry courses. The readily available Web-based program WebMO, in conjunction with the computational chemistry programs MOPAC and GAMESS, is used to quantitatively test a wide range of predictions of VSEPR. These predictions refer to the point group of the molecule, including the…
Testing by artificial intelligence: computational alternatives to the determination of mutagenicity.
Klopman, G; Rosenkranz, H S
1992-08-01
In order to develop methods for evaluating the predictive performance of computer-driven structure-activity methods (SAR) as well as to determine the limits of predictivity, we investigated the behavior of two Salmonella mutagenicity data bases: (a) a subset from the Genetox Program and (b) one from the U.S. National Toxicology Program (NTP). For molecules common to the two data bases, the experimental concordance was 76% when "marginals" were included and 81% when they were excluded. Three SAR methods were evaluated: CASE, MULTICASE and CASE/Graph Indices (CASE/GI). The programs "learned" the Genetox data base and used it to predict NTP molecules that were not present in the Genetox compilation. The concordances were 72, 80 and 47% respectively. Obviously, the MULTICASE version is superior and approaches the 85% interlaboratory variability observed for the Salmonella mutagenicity assays when the latter was carried out under carefully controlled conditions.
A computationally efficient modelling of laminar separation bubbles
NASA Technical Reports Server (NTRS)
Maughmer, Mark D.
1988-01-01
The goal of this research is to accurately predict the characteristics of the laminar separation bubble and its effects on airfoil performance. To this end, a model of the bubble is under development and will be incorporated in the analysis section of the Eppler and Somers program. As a first step in this direction, an existing bubble model was inserted into the program. It was decided to address the problem of the short bubble before attempting the prediction of the long bubble. In the second place, an integral boundary-layer method is believed more desirable than a finite difference approach. While these two methods achieve similar prediction accuracy, finite-difference methods tend to involve significantly longer computer run times than the integral methods. Finally, as the boundary-layer analysis in the Eppler and Somers program employs the momentum and kinetic energy integral equations, a short-bubble model compatible with these equations is most preferable.
Computing LORAN time differences with an HP-25 hand calculator
NASA Technical Reports Server (NTRS)
Jones, E. D.
1978-01-01
A program for an HP-25 or HP-25C hand calculator that will calculate accurate LORAN-C time differences is described and presented. The program is most useful when checking the accuracy of a LORAN-C receiver at a known latitude and longitude without the aid of an expensive computer. It can thus be used to compute time differences for known landmarks or waypoints to predict in advance the approximate readings during a navigation mission.
NASA Technical Reports Server (NTRS)
Rule, William Keith
1991-01-01
A computer program called BALLIST that is intended to be a design tool for engineers is described. BALLlST empirically predicts the bumper thickness required to prevent perforation of the Space Station pressure wall by a projectile (such as orbital debris) as a function of the projectile's velocity. 'Ballistic' limit curves (bumper thickness vs. projectile velocity) are calculated and are displayed on the screen as well as being stored in an ASCII file. A Whipple style of spacecraft wall configuration is assumed. The predictions are based on a database of impact test results. NASA/Marshall Space Flight Center currently has the capability to generate such test results. Numerical simulation results of impact conditions that can not be tested (high velocities or large particles) can also be used for predictions.
Computational structural mechanics for engine structures
NASA Technical Reports Server (NTRS)
Chamis, C. C.
1989-01-01
The computational structural mechanics (CSM) program at Lewis encompasses: (1) fundamental aspects for formulating and solving structural mechanics problems, and (2) development of integrated software systems to computationally simulate the performance/durability/life of engine structures. It is structured to mainly supplement, complement, and whenever possible replace, costly experimental efforts which are unavoidable during engineering research and development programs. Specific objectives include: investigate unique advantages of parallel and multiprocesses for: reformulating/solving structural mechanics and formulating/solving multidisciplinary mechanics and develop integrated structural system computational simulators for: predicting structural performances, evaluating newly developed methods, and for identifying and prioritizing improved/missing methods needed. Herein the CSM program is summarized with emphasis on the Engine Structures Computational Simulator (ESCS). Typical results obtained using ESCS are described to illustrate its versatility.
NASA Technical Reports Server (NTRS)
Mitchell, C. E.; Eckert, K.
1979-01-01
A program for predicting the linear stability of liquid propellant rocket engines is presented. The underlying model assumptions and analytical steps necessary for understanding the program and its input and output are also given. The rocket engine is modeled as a right circular cylinder with an injector with a concentrated combustion zone, a nozzle, finite mean flow, and an acoustic admittance, or the sensitive time lag theory. The resulting partial differential equations are combined into two governing integral equations by the use of the Green's function method. These equations are solved using a successive approximation technique for the small amplitude (linear) case. The computational method used as well as the various user options available are discussed. Finally, a flow diagram, sample input and output for a typical application and a complete program listing for program MODULE are presented.
Predictive Models and Computational Toxicology
Understanding the potential health risks posed by environmental chemicals is a significant challenge elevated by the large number of diverse chemicals with generally uncharacterized exposures, mechanisms, and toxicities. The ToxCast computational toxicology research program was l...
A Computer Program for Variable Density Yield Tables for Loblolly Pine Plantations
Clifford A. Myers
1977-01-01
The computer program described here uses relationships developed from research on loblolly pine growth to predict volumes and yields of planted stands, over the site range of the species, under a wide range of management alternatives. Timing and severity of thinnings, length of rotation, and type of harvest can be modified to compare the effects of various management...
Structural Optimization Methodology for Rotating Disks of Aircraft Engines
NASA Technical Reports Server (NTRS)
Armand, Sasan C.
1995-01-01
In support of the preliminary evaluation of various engine technologies, a methodology has been developed for structurally designing the rotating disks of an aircraft engine. The structural design methodology, along with a previously derived methodology for predicting low-cycle fatigue life, was implemented in a computer program. An interface computer program was also developed that gathers the required data from a flowpath analysis program (WATE) being used at NASA Lewis. The computer program developed for this study requires minimum interaction with the user, thus allowing engineers with varying backgrounds in aeropropulsion to successfully execute it. The stress analysis portion of the methodology and the computer program were verified by employing the finite element analysis method. The 10th- stage, high-pressure-compressor disk of the Energy Efficient Engine Program (E3) engine was used to verify the stress analysis; the differences between the stresses and displacements obtained from the computer program developed for this study and from the finite element analysis were all below 3 percent for the problem solved. The computer program developed for this study was employed to structurally optimize the rotating disks of the E3 high-pressure compressor. The rotating disks designed by the computer program in this study were approximately 26 percent lighter than calculated from the E3 drawings. The methodology is presented herein.
NASA Technical Reports Server (NTRS)
Huang, L. C. P.; Cook, R. A.
1973-01-01
Models utilizing various sub-sets of the six degrees of freedom are used in trajectory simulation. A 3-D model with only linear degrees of freedom is especially attractive, since the coefficients for the angular degrees of freedom are the most difficult to determine and the angular equations are the most time consuming for the computer to evaluate. A computer program is developed that uses three separate subsections to predict trajectories. A launch rail subsection is used until the rocket has left its launcher. The program then switches to a special 3-D section which computes motions in two linear and one angular degrees of freedom. When the rocket trims out, the program switches to the standard, three linear degrees of freedom model.
NASA Technical Reports Server (NTRS)
Lansing, F. L.
1979-01-01
A computer program which can distinguish between different receiver designs, and predict transient performance under variable solar flux, or ambient temperatures, etc. has a basic structure that fits a general heat transfer problem, but with specific features that are custom-made for solar receivers. The code is written in MBASIC computer language. The methodology followed in solving the heat transfer problem is explained. A program flow chart, an explanation of input and output tables, and an example of the simulation of a cavity-type solar receiver are included.
NASA Technical Reports Server (NTRS)
Spalding, D. B.; Launder, B. E.; Morse, A. P.; Maples, G.
1974-01-01
A guide to a computer program, written in FORTRAN 4, for predicting the flow properties of turbulent mixing with combustion of a circular jet of hydrogen into a co-flowing stream of air is presented. The program, which is based upon the Imperial College group's PASSA series, solves differential equations for diffusion and dissipation of turbulent kinetic energy and also of the R.M.S. fluctuation of hydrogen concentration. The effective turbulent viscosity for use in the shear stress equation is computed. Chemical equilibrium is assumed throughout the flow.
DOT National Transportation Integrated Search
1975-01-01
This report recommended that NOISE 3 initially use the same basic logic as the MICNOISE program for highway noise prediction except that additional options be made available, such as flexibility in specifying vehicle noise sources. A choice of six no...
ToxCast, the United States Environmental Protection Agency’s chemical prioritization research program, is developing methods for utilizing computational chemistry, bioactivity profiling and toxicogenomic data to predict potential for toxicity and prioritize limited testing resour...
A Computer Program for the Calculation of Three-Dimensional Transonic Nacelle/Inlet Flowfields
NASA Technical Reports Server (NTRS)
Vadyak, J.; Atta, E. H.
1983-01-01
A highly efficient computer analysis was developed for predicting transonic nacelle/inlet flowfields. This algorithm can compute the three dimensional transonic flowfield about axisymmetric (or asymmetric) nacelle/inlet configurations at zero or nonzero incidence. The flowfield is determined by solving the full-potential equation in conservative form on a body-fitted curvilinear computational mesh. The difference equations are solved using the AF2 approximate factorization scheme. This report presents a discussion of the computational methods used to both generate the body-fitted curvilinear mesh and to obtain the inviscid flow solution. Computed results and correlations with existing methods and experiment are presented. Also presented are discussions on the organization of the grid generation (NGRIDA) computer program and the flow solution (NACELLE) computer program, descriptions of the respective subroutines, definitions of the required input parameters for both algorithms, a brief discussion on interpretation of the output, and sample cases to illustrate application of the analysis.
NASA Technical Reports Server (NTRS)
1973-01-01
A shuttle (ARS) atmosphere revitalization subsystem active thermal control subsystem (ATCS) performance routine was developed. This computer program is adapted from the Shuttle EC/LSS Design Computer Program. The program was upgraded in three noteworthy areas: (1) The functional ARS/ATCS schematic has been revised to accurately synthesize the shuttle baseline system definition. (2) The program logic has been improved to provide a more accurate prediction of the integrated ARS/ATCS system performance. Additionally, the logic has been expanded to model all components and thermal loads in the ARS/ATCS system. (3) The program is designed to be used on the NASA JSC crew system division's programmable calculator system. As written the new computer routine has an average running time of five minutes. The use of desk top type calculation equipment, and the rapid response of the program provides the NASA with an analytical tool for trade studies to refine the system definition, and for test support of the RSECS or integrated Shuttle ARS/ATCS test programs.
User's manual for generalized ILSGLD-ILS glide slope performance prediction : multipath scattering
DOT National Transportation Integrated Search
1976-11-01
This manual presents the computer program package for the generalized ILSGLD scattering model. The text includes a complete description of the program itself as well as 3 brief descriptions : of the ILS system and antenna patterns. The program listin...
Validation of the Unthinned Loblolly Pine Plantation Yield Model-USLYCOWG
V. Clark Baldwin; D.P. Feduccia
1982-01-01
Yield and stand structure predictions from an unthinned loblolly pine plantation yield prediction system (USLYCOWG computer program) were compared with observations from 80 unthinned loblolly pine plots. Overall, the predicted estimates were reasonable when compared to observed values, but predictions based on input data at or near the system's limits may be in...
A computer program for analyzing the energy consumption of automatically controlled lighting systems
NASA Astrophysics Data System (ADS)
1982-01-01
A computer code to predict the performance of controlled lighting systems with respect to their energy saving capabilities is presented. The computer program provides a mathematical model from which comparisons of control schemes can be made on an economic basis only. The program does not calculate daylighting, but uses daylighting values as input. The program can analyze any of three power input versus light output relationships, continuous dimming with a linear response, continuous dimming with a nonlinear response, or discrete stepped response. Any of these options can be used with or without daylighting, making six distinct modes of control system operation. These relationships are described in detail. The major components of the program are discussed and examples are included to explain how to run the program.
Validation of the solar heating and cooling high speed performance (HISPER) computer code
NASA Technical Reports Server (NTRS)
Wallace, D. B.
1980-01-01
Developed to give a quick and accurate predictions HISPER, a simplification of the TRNSYS program, achieves its computational speed by not simulating detailed system operations or performing detailed load computations. In order to validate the HISPER computer for air systems the simulation was compared to the actual performance of an operational test site. Solar insolation, ambient temperature, water usage rate, and water main temperatures from the data tapes for an office building in Huntsville, Alabama were used as input. The HISPER program was found to predict the heating loads and solar fraction of the loads with errors of less than ten percent. Good correlation was found on both a seasonal basis and a monthly basis. Several parameters (such as infiltration rate and the outside ambient temperature above which heating is not required) were found to require careful selection for accurate simulation.
Computer Program for the Design and Off-Design Performance of Turbojet and Turbofan Engine Cycles
NASA Technical Reports Server (NTRS)
Morris, S. J.
1978-01-01
The rapid computer program is designed to be run in a stand-alone mode or operated within a larger program. The computation is based on a simplified one-dimensional gas turbine cycle. Each component in the engine is modeled thermo-dynamically. The component efficiencies used in the thermodynamic modeling are scaled for the off-design conditions from input design point values using empirical trends which are included in the computer code. The engine cycle program is capable of producing reasonable engine performance prediction with a minimum of computer execute time. The current computer execute time on the IBM 360/67 for one Mach number, one altitude, and one power setting is about 0.1 seconds. about 0.1 seconds. The principal assumption used in the calculation is that the compressor is operated along a line of maximum adiabatic efficiency on the compressor map. The fluid properties are computed for the combustion mixture, but dissociation is not included. The procedure included in the program is only for the combustion of JP-4, methane, or hydrogen.
NASA Technical Reports Server (NTRS)
Putnam, L. E.
1979-01-01
A Neumann solution for inviscid external flow was coupled to a modified Reshotko-Tucker integral boundary-layer technique, the control volume method of Presz for calculating flow in the separated region, and an inviscid one-dimensional solution for the jet exhaust flow in order to predict axisymmetric nozzle afterbody pressure distributions and drag. The viscous and inviscid flows are solved iteratively until convergence is obtained. A computer algorithm of this procedure was written and is called DONBOL. A description of the computer program and a guide to its use is given. Comparisons of the predictions of this method with experiments show that the method accurately predicts the pressure distributions of boattail afterbodies which have the jet exhaust flow simulated by solid bodies. For nozzle configurations which have the jet exhaust simulated by high-pressure air, the present method significantly underpredicts the magnitude of nozzle pressure drag. This deficiency results because the method neglects the effects of jet plume entrainment. This method is limited to subsonic free-stream Mach numbers below that for which the flow over the body of revolution becomes sonic.
NASA Technical Reports Server (NTRS)
Bains, R. W.; Herwig, H. A.; Luedeman, J. K.; Torina, E. M.
1974-01-01
The Shuttle Electric Power System Analysis SEPS computer program which performs detailed load analysis including predicting energy demands and consumables requirements of the shuttle electric power system along with parameteric and special case studies on the shuttle electric power system is described. The functional flow diagram of the SEPS program is presented along with data base requirements and formats, procedure and activity definitions, and mission timeline input formats. Distribution circuit input and fixed data requirements are included. Run procedures and deck setups are described.
Universe creation on a computer
NASA Astrophysics Data System (ADS)
McCabe, Gordon
The purpose of this paper is to provide an account of the epistemology and metaphysics of universe creation on a computer. The paper begins with F.J. Tipler's argument that our experience is indistinguishable from the experience of someone embedded in a perfect computer simulation of our own universe, hence we cannot know whether or not we are part of such a computer program ourselves. Tipler's argument is treated as a special case of epistemological scepticism, in a similar vein to 'brain-in-a-vat' arguments. It is argued that Tipler's hypothesis that our universe is a program running on a digital computer in another universe, generates empirical predictions, and is therefore a falsifiable hypothesis. The computer program hypothesis is also treated as a hypothesis about what exists beyond the physical world, and is compared with Kant's metaphysics of noumena. It is argued that if our universe is a program running on a digital computer, then our universe must have compact spatial topology, and the possibilities of observationally testing this prediction are considered. The possibility of testing the computer program hypothesis with the value of the density parameter Ω0 is also analysed. The informational requirements for a computer to represent a universe exactly and completely are considered. Consequent doubt is thrown upon Tipler's claim that if a hierarchy of computer universes exists, we would not be able to know which 'level of implementation' our universe exists at. It is then argued that a digital computer simulation of a universe, or any other physical system, does not provide a realisation of that universe or system. It is argued that a digital computer simulation of a physical system is not objectively related to that physical system, and therefore cannot exist as anything else other than a physical process occurring upon the components of the computer. It is concluded that Tipler's sceptical hypothesis, and a related hypothesis from Bostrom, cannot be true: it is impossible that our own experience is indistinguishable from the experience of somebody embedded in a digital computer simulation because it is impossible for anybody to be embedded in a digital computer simulation.
Addition of flexible body option to the TOLA computer program, part 1
NASA Technical Reports Server (NTRS)
Dick, J. W.; Benda, B. J.
1975-01-01
This report describes a flexible body option that was developed and added to the Takeoff and Landing Analysis (TOLA) computer program. The addition of the flexible body option to TOLA allows it to be used to study essentially any conventional type airplane in the ground operating environment. It provides the capability to predict the total motion of selected points on the analytical methods incorporated in the program and operating instructions for the option are described. A program listing is included along with several example problems to aid in interpretation of the operating instructions and to illustrate program usage.
Data Structures for Extreme Scale Computing
DOE Office of Scientific and Technical Information (OSTI.GOV)
Kahan, Simon
As computing problems of national importance grow, the government meets the increased demand by funding the development of ever larger systems. The overarching goal of the work supported in part by this grant is to increase efficiency of programming and performing computations on these large computing systems. In past work, we have demonstrated that some of these computations once thought to require expensive hardware designs and/or complex, special-purpose programming may be executed efficiently on low-cost commodity cluster computing systems using a general-purpose “latency-tolerant” programming framework. One important developed application of the ideas underlying this framework is graph database technology supportingmore » social network pattern matching used by US intelligence agencies to more quickly identify potential terrorist threats. This database application has been spun out by the Pacific Northwest National Laboratory, a Department of Energy Laboratory, into a commercial start-up, Trovares Inc. We explore an alternative application of the same underlying ideas to a well-studied challenge arising in engineering: solving unstructured sparse linear equations. Solving these equations is key to predicting the behavior of large electronic circuits before they are fabricated. Predicting that behavior ahead of fabrication means that designs can optimized and errors corrected ahead of the expense of manufacture.« less
ToxCast: Developing Predictive Signatures of Chemically Induced Toxicity (S)
ToxCast, the United States Environmental Protection Agency’s chemical prioritization research program, is developing methods for utilizing computational chemistry, bioactivity profiling and toxicogenomic data to predict potential for toxicity and prioritize limited testing resour...
Acoustic radiation from lined, unflanged ducts: Acoustic source distribution program
NASA Technical Reports Server (NTRS)
Beckemeyer, R. J.; Sawdy, D. T.
1971-01-01
An acoustic radiation analysis was developed to predict the far-field characteristics of fan noise radiated from an acoustically lined unflanged duct. This analysis is comprised of three modular digital computer programs which together provide a capability of accounting for the impedance mismatch at the duct exit plane. Admissible duct configurations include circular or annular, with or without an extended centerbody. This variation in duct configurations provides a capability of modeling inlet and fan duct noise radiation. The computer programs are described in detail.
Program Aids Design Of Fluid-Circulating Systems
NASA Technical Reports Server (NTRS)
Bacskay, Allen; Dalee, Robert
1992-01-01
Computer Aided Systems Engineering and Analysis (CASE/A) program is interactive software tool for trade study and analysis, designed to increase productivity during all phases of systems engineering. Graphics-based command-driven software package provides user-friendly computing environment in which engineer analyzes performance and interface characteristics of ECLS/ATC system. Useful during all phases of spacecraft-design program, from initial conceptual design trade studies to actual flight, including pre-flight prediction and in-flight analysis of anomalies. Written in FORTRAN 77.
Study of improved modeling and solution procedures for nonlinear analysis. [aircraft-like structures
NASA Technical Reports Server (NTRS)
Kamat, M. P.
1979-01-01
An evaluation of the ACTION computer code on an aircraft like structure is presented. This computer program proved adequate in predicting gross response parameters in structures which undergo severe localized cross sectional deformations.
DOT National Transportation Integrated Search
1976-01-01
This report provides a detailed explanation of the inner workings of the computer program AIRPOL-4A, a computer model for predicting the impact of highway generated air pollution. The report is intended to serve both as a supportive document for AIRP...
Accessible high-throughput virtual screening molecular docking software for students and educators.
Jacob, Reed B; Andersen, Tim; McDougal, Owen M
2012-05-01
We survey low cost high-throughput virtual screening (HTVS) computer programs for instructors who wish to demonstrate molecular docking in their courses. Since HTVS programs are a useful adjunct to the time consuming and expensive wet bench experiments necessary to discover new drug therapies, the topic of molecular docking is core to the instruction of biochemistry and molecular biology. The availability of HTVS programs coupled with decreasing costs and advances in computer hardware have made computational approaches to drug discovery possible at institutional and non-profit budgets. This paper focuses on HTVS programs with graphical user interfaces (GUIs) that use either DOCK or AutoDock for the prediction of DockoMatic, PyRx, DockingServer, and MOLA since their utility has been proven by the research community, they are free or affordable, and the programs operate on a range of computer platforms.
NASA Technical Reports Server (NTRS)
Pan, Y. S.
1978-01-01
A three dimensional, partially elliptic, computer program was developed. Without requiring three dimensional computer storage locations for all flow variables, the partially elliptic program is capable of predicting three dimensional combustor flow fields with large downstream effects. The program requires only slight increase of computer storage over the parabolic flow program from which it was developed. A finite difference formulation for a three dimensional, fully elliptic, turbulent, reacting, flow field was derived. Because of the negligible diffusion effects in the main flow direction in a supersonic combustor, the set of finite-difference equations can be reduced to a partially elliptic form. Only the pressure field was governed by an elliptic equation and requires three dimensional storage; all other dependent variables are governed by parabolic equations. A numerical procedure which combines a marching integration scheme with an iterative scheme for solving the elliptic pressure was adopted.
NASA Technical Reports Server (NTRS)
Egolf, T. Alan; Anderson, Olof L.; Edwards, David E.; Landgrebe, Anton J.
1988-01-01
A computer program, the Propeller Nacelle Aerodynamic Performance Prediction Analysis (PANPER), was developed for the prediction and analysis of the performance and airflow of propeller-nacelle configurations operating over a forward speed range inclusive of high speed flight typical of recent propfan designs. A propeller lifting line, wake program was combined with a compressible, viscous center body interaction program, originally developed for diffusers, to compute the propeller-nacelle flow field, blade loading distribution, propeller performance, and the nacelle forebody pressure and viscous drag distributions. The computer analysis is applicable to single and coaxial counterrotating propellers. The blade geometries can include spanwise variations in sweep, droop, taper, thickness, and airfoil section type. In the coaxial mode of operation the analysis can treat both equal and unequal blade number and rotational speeds on the propeller disks. The nacelle portion of the analysis can treat both free air and tunnel wall configurations including wall bleed. The analysis was applied to many different sets of flight conditions using selected aerodynamic modeling options. The influence of different propeller nacelle-tunnel wall configurations was studied. Comparisons with available test data for both single and coaxial propeller configurations are presented along with a discussion of the results.
Demonstration of the Water Erosion Prediction Project (WEPP) internet interface and services
USDA-ARS?s Scientific Manuscript database
The Water Erosion Prediction Project (WEPP) model is a process-based FORTRAN computer simulation program for prediction of runoff and soil erosion by water at hillslope profile, field, and small watershed scales. To effectively run the WEPP model and interpret results additional software has been de...
An evaluation of Space Shuttle STS-2 payload bay acoustic data and comparison with predictions
NASA Technical Reports Server (NTRS)
Wilby, J. F.; Piersol, A. G.; Wilby, E. G.
1982-01-01
Space average sound pressure levels computed from measurements at 18 locations in the payload bay of the Space Shuttle orbiter vehicle during the STS-2 launch were compared with predicted levels obtained using the PACES computer program. The comparisons were performed over the frequency range 12.5 Hz to 1000 Hz, since the test data at higher frequencies are contaminated by instrumentation background noise. In general the PACES computer program tends to overpredict the space average sound levels in the payload bay, although the magnitude of the discrepancy is usually small. Furthermore the discrepancy depends to some extent on the manner in which the payload is modeled analytically, and the method used to determine the "measured' space average sound pressure levels. Thus the difference between predicted and measured sound levels, averaged over the 20 one third octave bands from 12.5 Hz to 1000 Hz, varies from 1 dB to 3.5 dB.
NASA Technical Reports Server (NTRS)
Everhart, J. L.
1983-01-01
A program called FLEXWAL for calculating wall modifications for solid, adaptive-wall wind tunnels is presented. The method used is the iterative technique of NASA TP-2081 and is applicable to subsonic and transonic test conditions. The program usage, program listing, and a sample case are given.
NASA Technical Reports Server (NTRS)
1971-01-01
Computational techniques were developed and assimilated for the design optimization. The resulting computer program was then used to perform initial optimization and sensitivity studies on a typical thermal protection system (TPS) to demonstrate its application to the space shuttle TPS design. The program was developed in Fortran IV for the CDC 6400 but was subsequently converted to the Fortran V language to be used on the Univac 1108. The program allows for improvement and update of the performance prediction techniques. The program logic involves subroutines which handle the following basic functions: (1) a driver which calls for input, output, and communication between program and user and between the subroutines themselves; (2) thermodynamic analysis; (3) thermal stress analysis; (4) acoustic fatigue analysis; and (5) weights/cost analysis. In addition, a system total cost is predicted based on system weight and historical cost data of similar systems. Two basic types of input are provided, both of which are based on trajectory data. These are vehicle attitude (altitude, velocity, and angles of attack and sideslip), for external heat and pressure loads calculation, and heating rates and pressure loads as a function of time.
NASA Technical Reports Server (NTRS)
Patterson, G.
1973-01-01
The data processing procedures and the computer programs were developed to predict structural responses using the Impulse Transfer Function (ITF) method. There are three major steps in the process: (1) analog-to-digital (A-D) conversion of the test data to produce Phase I digital tapes (2) processing of the Phase I digital tapes to extract ITF's and storing them in a permanent data bank, and (3) predicting structural responses to a set of applied loads. The analog to digital conversion is performed by a standard package which will be described later in terms of the contents of the resulting Phase I digital tape. Two separate computer programs have been developed to perform the digital processing.
Zero-G Thermodynamic Venting System (TVS) Performance Prediction Program
NASA Technical Reports Server (NTRS)
Nguyen, Han
1994-01-01
This report documents the Zero-g Thermodynamic Venting System (TVS) performance prediction computer program. The zero-g TVS is a device that destratifies and rejects environmentally induced zero-g thermal gradients in the LH2 storage transfer system. A recirculation pump and spray injection manifold recirculates liquid throughout the length of the tank thereby destratifying both the ullage gas and liquid bulk. Heat rejection is accomplished by the opening of the TVS control valve which allows a small flow rate to expand to a low pressure thereby producing a low temperature heat sink which is used to absorb heat from the recirculating liquid flow. The program was written in FORTRAN 77 language on the HP-9000 and IBM PC computers. It can be run on various platforms with a FORTRAN compiler.
Parental Perceptions and Recommendations of Computing Majors: A Technology Acceptance Model Approach
ERIC Educational Resources Information Center
Powell, Loreen; Wimmer, Hayden
2017-01-01
Currently, there are more technology related jobs then there are graduates in supply. The need to understand user acceptance of computing degrees is the first step in increasing enrollment in computing fields. Additionally, valid measurement scales for predicting user acceptance of Information Technology degree programs are required. The majority…
R.B. Ferguson; V. Clark Baldwin
1987-01-01
Complete instructions for user operation of COMPUTE_P-LOB to include detailed examples of computer input and output, of a growth and yield prediction system providing volume and weight yields in stand and stock table format.A complete program listing is provided.
Ecological Structure Activity Relationships
Ecological Structure Activity Relationships, v1.00a, February 2009
ECOSAR (Ecological Structure Activity Relationships) is a personal computer software program that is used to estimate the toxicity of chemicals used in industry and discharged into water. The program predicts...
Interactive computer programs for the graphic analysis of nucleotide sequence data.
Luckow, V A; Littlewood, R K; Rownd, R H
1984-01-01
A group of interactive computer programs have been developed which aid in the collection and graphical analysis of nucleotide and protein sequence data. The programs perform the following basic functions: a) enter, edit, list, and rearrange sequence data; b) permit automatic entry of nucleotide sequence data directly from an autoradiograph into the computer; c) search for restriction sites or other specified patterns and plot a linear or circular restriction map, or print their locations; d) plot base composition; e) analyze homology between sequences by plotting a two-dimensional graphic matrix; and f) aid in plotting predicted secondary structures of RNA molecules. PMID:6546437
The vehicle design evaluation program - A computer-aided design procedure for transport aircraft
NASA Technical Reports Server (NTRS)
Oman, B. H.; Kruse, G. S.; Schrader, O. E.
1977-01-01
The vehicle design evaluation program is described. This program is a computer-aided design procedure that provides a vehicle synthesis capability for vehicle sizing, external load analysis, structural analysis, and cost evaluation. The vehicle sizing subprogram provides geometry, weight, and balance data for aircraft using JP, hydrogen, or methane fuels. The structural synthesis subprogram uses a multistation analysis for aerodynamic surfaces and fuselages to develop theoretical weights and geometric dimensions. The parts definition subprogram uses the geometric data from the structural analysis and develops the predicted fabrication dimensions, parts material raw stock buy requirements, and predicted actual weights. The cost analysis subprogram uses detail part data in conjunction with standard hours, realization factors, labor rates, and material data to develop the manufacturing costs. The program is used to evaluate overall design effects on subsonic commercial type aircraft due to parameter variations.
New technology in turbine aerodynamics.
NASA Technical Reports Server (NTRS)
Glassman, A. J.; Moffitt, T. P.
1972-01-01
Cursory review of some recent work that has been done in turbine aerodynamic research. Topics discussed include the aerodynamic effect of turbine coolant, high work-factor (ratio of stage work to square of blade speed) turbines, and computer methods for turbine design and performance prediction. Experimental cooled-turbine aerodynamics programs using two-dimensional cascades, full annular cascades, and cold rotating turbine stage tests are discussed with some typical results presented. Analytically predicted results for cooled blade performance are compared to experimental results. The problems and some of the current programs associated with the use of very high work factors for fan-drive turbines of high-bypass-ratio engines are discussed. Computer programs have been developed for turbine design-point performance, off-design performance, supersonic blade profile design, and the calculation of channel velocities for subsonic and transonic flowfields. The use of these programs for the design and analysis of axial and radial turbines is discussed.
Prediction of sound radiated from different practical jet engine inlets
NASA Technical Reports Server (NTRS)
Zinn, B. T.; Meyer, W. L.
1980-01-01
Existing computer codes for calculating the far field radiation patterns surrounding various practical jet engine inlet configurations under different excitation conditions were upgraded. The computer codes were refined and expanded so that they are now more efficient computationally by a factor of about three and they are now capable of producing accurate results up to nondimensional wave numbers of twenty. Computer programs were also developed to help generate accurate geometrical representations of the inlets to be investigated. This data is required as input for the computer programs which calculate the sound fields. This new geometry generating computer program considerably reduces the time required to generate the input data which was one of the most time consuming steps in the process. The results of sample runs using the NASA-Lewis QCSEE inlet are presented and comparison of run times and accuracy are made between the old and upgraded computer codes. The overall accuracy of the computations is determined by comparison of the results of the computations with simple source solutions.
An emulator for minimizing computer resources for finite element analysis
NASA Technical Reports Server (NTRS)
Melosh, R.; Utku, S.; Islam, M.; Salama, M.
1984-01-01
A computer code, SCOPE, has been developed for predicting the computer resources required for a given analysis code, computer hardware, and structural problem. The cost of running the code is a small fraction (about 3 percent) of the cost of performing the actual analysis. However, its accuracy in predicting the CPU and I/O resources depends intrinsically on the accuracy of calibration data that must be developed once for the computer hardware and the finite element analysis code of interest. Testing of the SCOPE code on the AMDAHL 470 V/8 computer and the ELAS finite element analysis program indicated small I/O errors (3.2 percent), larger CPU errors (17.8 percent), and negligible total errors (1.5 percent).
Using NCAP to predict RFI effects in linear bipolar integrated circuits
NASA Astrophysics Data System (ADS)
Fang, T.-F.; Whalen, J. J.; Chen, G. K. C.
1980-11-01
Applications of the Nonlinear Circuit Analysis Program (NCAP) to calculate RFI effects in electronic circuits containing discrete semiconductor devices have been reported upon previously. The objective of this paper is to demonstrate that the computer program NCAP also can be used to calcuate RFI effects in linear bipolar integrated circuits (IC's). The IC's reported upon are the microA741 operational amplifier (op amp) which is one of the most widely used IC's, and a differential pair which is a basic building block in many linear IC's. The microA741 op amp was used as the active component in a unity-gain buffer amplifier. The differential pair was used in a broad-band cascode amplifier circuit. The computer program NCAP was used to predict how amplitude-modulated RF signals are demodulated in the IC's to cause undesired low-frequency responses. The predicted and measured results for radio frequencies in the 0.050-60-MHz range are in good agreement.
Power subsystem performance prediction /PSPP/ computer program.
NASA Technical Reports Server (NTRS)
Weiner, H.; Weinstein, S.
1972-01-01
A computer program which simulates the operation of the Viking Orbiter Power Subsystem has been developed. The program simulates the characteristics and interactions of a solar array, battery, battery charge controls, zener diodes, power conditioning equipment, and the battery spacecraft and zener diode-spacecraft thermal interfaces. This program has been used to examine the operation of the Orbiter power subsystem during critical phases of the Viking mission - from launch, through midcourse maneuvers, Mars orbital insertion, orbital trims, Lander separation, solar occultations and unattended operation - until the end of the mission. A typical computer run for the first 24 hours after launch is presented which shows the variations in solar array, zener diode, battery charger, batteries and user load characteristics during this period.
Thermal radiation view factor: Methods, accuracy and computer-aided procedures
NASA Technical Reports Server (NTRS)
Kadaba, P. V.
1982-01-01
The computer aided thermal analysis programs which predicts the result of predetermined acceptable temperature range prior to stationing of these orbiting equipment in various attitudes with respect to the Sun and the Earth was examined. Complexity of the surface geometries suggests the use of numerical schemes for the determination of these viewfactors. Basic definitions and standard methods which form the basis for various digital computer methods and various numerical methods are presented. The physical model and the mathematical methods on which a number of available programs are built are summarized. The strength and the weaknesses of the methods employed, the accuracy of the calculations and the time required for computations are evaluated. The situations where accuracies are important for energy calculations are identified and methods to save computational times are proposed. Guide to best use of the available programs at several centers and the future choices for efficient use of digital computers are included in the recommendations.
NASA Technical Reports Server (NTRS)
Chiappetta, L. M.
1983-01-01
Described is a computer program for the analysis of the subsonic, swirling, reacting turbulent flow in an axisymmetric, bluff-body research combustor. The program features an improved finite-difference procedure designed to reduce the effects of numerical diffusion and a new algorithm for predicting the pressure distribution within the combustor. A research version of the computer program described in the report was supplied to United Technologies Research Center by Professor A. D. Gosman and his students, R. Benodeker and R. I. Issa, of Imperial College, London. The Imperial College staff also supplied much of the program documentation. Presented are a description of the mathematical model for flow within an axisymmetric bluff-body combustor, the development of the finite-difference procedure used to represent the system of equations, an outline of the algorithm for determining the static pressure distribution within the combustor, a description of the computer program including its input format, and the results for representative test cases.
An analytical procedure for evaluating shuttle abort staging aerodynamic characteristics
NASA Technical Reports Server (NTRS)
Meyer, R.
1973-01-01
An engineering analysis and computer code (AERSEP) for predicting Space Shuttle Orbiter - HO Tank longitudinal aerodynamic characteristics during abort separation has been developed. Computed results are applicable at Mach numbers above 2 for angle-of-attack between plus or minus 10 degrees. No practical restrictions on orbiter-tank relative positioning are indicated for tank-under-orbiter configurations. Input data requirements and computer running times are minimal facilitating program use for parametric studies, test planning, and trajectory analysis. In a majority of cases AERSEP Orbiter-Tank interference predictions are as accurate as state-of-the-art estimates for interference-free or isolated-vehicle configurations. AERSEP isolated-orbiter predictions also show excellent correlation with data.
NASA Technical Reports Server (NTRS)
Chin, M. M.; Goad, C. C.; Martin, T. V.
1972-01-01
A computer program for the estimation of orbit and geodetic parameters is presented. The areas in which the program is operational are defined. The specific uses of the program are given as: (1) determination of definitive orbits, (2) tracking instrument calibration, (3) satellite operational predictions, and (4) geodetic parameter estimation. The relationship between the various elements in the solution of the orbit and geodetic parameter estimation problem is analyzed. The solution of the problems corresponds to the orbit generation mode in the first case and to the data reduction mode in the second case.
Analysis of Compression Pad Cavities for the Orion Heatshield
NASA Technical Reports Server (NTRS)
Thompson, Richard A.; Lessard, Victor R.; Jentink, Thomas N.; Zoby, Ernest V.
2009-01-01
Current results of a program for analysis of the compression pad cavities on the Orion heatshield are reviewed. The program was supported by experimental tests, engineering modeling, and applied computations with an emphasis on the latter presented in this paper. The computational tools and approach are described along with calculated results for wind tunnel and flight conditions. Correlations of the computed results are shown which can produce a credible prediction of heating augmentation due to cavity disturbances. The models developed for use in preliminary design of the Orion heatshield are presented.
Predictive In Vitro Screening of Environmental Chemicals – The ToxCast Project
ToxCast, the United States Environmental Protection Agency’s chemical prioritization research program, is developing methods for utilizing computational chemistry and bioactivity profiling to predict potential for toxicity and prioritize limited testing resources (www.epa.gov/toc...
EPA is developing methods for utilizing computational chemistry, high-throughput screening (HTS) and various toxicogenomic technologies to predict potential for toxicity and prioritize limited testing resources towards chemicals that likely represent the greatest hazard to human ...
NASA Technical Reports Server (NTRS)
Spilker, R. L.; Witmer, E. A.; French, S. E.; Rodal, J. J. A.
1980-01-01
Two computer programs are described for predicting the transient large deflection elastic viscoplastic responses of thin single layer, initially flat unstiffened or integrally stiffened, Kirchhoff-Lov ductile metal panels. The PLATE 1 program pertains to structural responses produced by prescribed externally applied transient loading or prescribed initial velocity distributions. The collision imparted velocity method PLATE 1 program concerns structural responses produced by impact of an idealized nondeformable fragment. Finite elements are used to represent the structure in both programs. Strain hardening and strain rate effects of initially isotropic material are considered.
THRESHOLD LOGIC IN ARTIFICIAL INTELLIGENCE
COMPUTER LOGIC, ARTIFICIAL INTELLIGENCE , BIONICS, GEOMETRY, INPUT OUTPUT DEVICES, LINEAR PROGRAMMING, MATHEMATICAL LOGIC, MATHEMATICAL PREDICTION, NETWORKS, PATTERN RECOGNITION, PROBABILITY, SWITCHING CIRCUITS, SYNTHESIS
ERIC Educational Resources Information Center
Debrabant, Julie; Gheysen, Freja; Caeyenberghs, Karen; Van Waelvelde, Hilde; Vingerhoets, Guy
2013-01-01
A dysfunction in predictive motor timing is put forward to underlie DCD-related motor problems. Predictive timing allows for the pre-selection of motor programmes (except "program" in computers) in order to decrease processing load and facilitate reactions. Using functional magnetic resonance imaging (fMRI), this study investigated the neural…
Ku-Band rendezvous radar performance computer simulation model
NASA Technical Reports Server (NTRS)
Magnusson, H. G.; Goff, M. F.
1984-01-01
All work performed on the Ku-band rendezvous radar performance computer simulation model program since the release of the preliminary final report is summarized. Developments on the program fall into three distinct categories: (1) modifications to the existing Ku-band radar tracking performance computer model; (2) the addition of a highly accurate, nonrealtime search and acquisition performance computer model to the total software package developed on this program; and (3) development of radar cross section (RCS) computation models for three additional satellites. All changes in the tracking model involved improvements in the automatic gain control (AGC) and the radar signal strength (RSS) computer models. Although the search and acquisition computer models were developed under the auspices of the Hughes Aircraft Company Ku-Band Integrated Radar and Communications Subsystem program office, they have been supplied to NASA as part of the Ku-band radar performance comuter model package. Their purpose is to predict Ku-band acquisition performance for specific satellite targets on specific missions. The RCS models were developed for three satellites: the Long Duration Exposure Facility (LDEF) spacecraft, the Solar Maximum Mission (SMM) spacecraft, and the Space Telescopes.
Ku-Band rendezvous radar performance computer simulation model
NASA Astrophysics Data System (ADS)
Magnusson, H. G.; Goff, M. F.
1984-06-01
All work performed on the Ku-band rendezvous radar performance computer simulation model program since the release of the preliminary final report is summarized. Developments on the program fall into three distinct categories: (1) modifications to the existing Ku-band radar tracking performance computer model; (2) the addition of a highly accurate, nonrealtime search and acquisition performance computer model to the total software package developed on this program; and (3) development of radar cross section (RCS) computation models for three additional satellites. All changes in the tracking model involved improvements in the automatic gain control (AGC) and the radar signal strength (RSS) computer models. Although the search and acquisition computer models were developed under the auspices of the Hughes Aircraft Company Ku-Band Integrated Radar and Communications Subsystem program office, they have been supplied to NASA as part of the Ku-band radar performance comuter model package. Their purpose is to predict Ku-band acquisition performance for specific satellite targets on specific missions. The RCS models were developed for three satellites: the Long Duration Exposure Facility (LDEF) spacecraft, the Solar Maximum Mission (SMM) spacecraft, and the Space Telescopes.
GAPIT: genome association and prediction integrated tool.
Lipka, Alexander E; Tian, Feng; Wang, Qishan; Peiffer, Jason; Li, Meng; Bradbury, Peter J; Gore, Michael A; Buckler, Edward S; Zhang, Zhiwu
2012-09-15
Software programs that conduct genome-wide association studies and genomic prediction and selection need to use methodologies that maximize statistical power, provide high prediction accuracy and run in a computationally efficient manner. We developed an R package called Genome Association and Prediction Integrated Tool (GAPIT) that implements advanced statistical methods including the compressed mixed linear model (CMLM) and CMLM-based genomic prediction and selection. The GAPIT package can handle large datasets in excess of 10 000 individuals and 1 million single-nucleotide polymorphisms with minimal computational time, while providing user-friendly access and concise tables and graphs to interpret results. http://www.maizegenetics.net/GAPIT. zhiwu.zhang@cornell.edu Supplementary data are available at Bioinformatics online.
First Order Fire Effects Model: FOFEM 4.0, user's guide
Elizabeth D. Reinhardt; Robert E. Keane; James K. Brown
1997-01-01
A First Order Fire Effects Model (FOFEM) was developed to predict the direct consequences of prescribed fire and wildfire. FOFEM computes duff and woody fuel consumption, smoke production, and fire-caused tree mortality for most forest and rangeland types in the United States. The model is available as a computer program for PC or Data General computer.
Federal Register 2010, 2011, 2012, 2013, 2014
2012-06-20
... analysis and design, and computer software design and coding. Given the fact that over $500 million were... acoustic algorithms, computer architecture, and source code that dated to the 1970s. Since that time... 2012. Version 3.0 is an entirely new, state-of-the-art computer program used for predicting noise...
Interior noise prediction methodology: ATDAC theory and validation
NASA Technical Reports Server (NTRS)
Mathur, Gopal P.; Gardner, Bryce K.
1992-01-01
The Acoustical Theory for Design of Aircraft Cabins (ATDAC) is a computer program developed to predict interior noise levels inside aircraft and to evaluate the effects of different aircraft configurations on the aircraft acoustical environment. The primary motivation for development of this program is the special interior noise problems associated with advanced turboprop (ATP) aircraft where there is a tonal, low frequency noise problem. Prediction of interior noise levels requires knowledge of the energy sources, the transmission paths, and the relationship between the energy variable and the sound pressure level. The energy sources include engine noise, both airborne and structure-borne; turbulent boundary layer noise; and interior noise sources such as air conditioner noise and auxiliary power unit noise. Since propeller and engine noise prediction programs are widely available, they are not included in ATDAC. Airborne engine noise from any prediction or measurement may be input to this program. This report describes the theory and equations implemented in the ATDAC program.
Interior noise prediction methodology: ATDAC theory and validation
NASA Astrophysics Data System (ADS)
Mathur, Gopal P.; Gardner, Bryce K.
1992-04-01
The Acoustical Theory for Design of Aircraft Cabins (ATDAC) is a computer program developed to predict interior noise levels inside aircraft and to evaluate the effects of different aircraft configurations on the aircraft acoustical environment. The primary motivation for development of this program is the special interior noise problems associated with advanced turboprop (ATP) aircraft where there is a tonal, low frequency noise problem. Prediction of interior noise levels requires knowledge of the energy sources, the transmission paths, and the relationship between the energy variable and the sound pressure level. The energy sources include engine noise, both airborne and structure-borne; turbulent boundary layer noise; and interior noise sources such as air conditioner noise and auxiliary power unit noise. Since propeller and engine noise prediction programs are widely available, they are not included in ATDAC. Airborne engine noise from any prediction or measurement may be input to this program. This report describes the theory and equations implemented in the ATDAC program.
Evaluation of the three-dimensional parabolic flow computer program SHIP
NASA Technical Reports Server (NTRS)
Pan, Y. S.
1978-01-01
The three-dimensional parabolic flow program SHIP designed for predicting supersonic combustor flow fields is evaluated to determine its capabilities. The mathematical foundation and numerical procedure are reviewed; simplifications are pointed out and commented upon. The program is then evaluated numerically by applying it to several subsonic and supersonic, turbulent, reacting and nonreacting flow problems. Computational results are compared with available experimental or other analytical data. Good agreements are obtained when the simplifications on which the program is based are justified. Limitations of the program and the needs for improvement and extension are pointed out. The present three dimensional parabolic flow program appears to be potentially useful for the development of supersonic combustors.
Navy Enhanced Sierra Mechanics (NESM): Toolbox for predicting Navy shock and damage
DOE Office of Scientific and Technical Information (OSTI.GOV)
Moyer, Thomas; Stergiou, Jonathan; Reese, Garth
Here, the US Navy is developing a new suite of computational mechanics tools (Navy Enhanced Sierra Mechanics) for the prediction of ship response, damage, and shock environments transmitted to vital systems during threat weapon encounters. NESM includes fully coupled Euler-Lagrange solvers tailored to ship shock/damage predictions. NESM is optimized to support high-performance computing architectures, providing the physics-based ship response/threat weapon damage predictions needed to support the design and assessment of highly survivable ships. NESM is being employed to support current Navy ship design and acquisition programs while being further developed for future Navy fleet needs.
A computational cognitive model of self-efficacy and daily adherence in mHealth.
Pirolli, Peter
2016-12-01
Mobile health (mHealth) applications provide an excellent opportunity for collecting rich, fine-grained data necessary for understanding and predicting day-to-day health behavior change dynamics. A computational predictive model (ACT-R-DStress) is presented and fit to individual daily adherence in 28-day mHealth exercise programs. The ACT-R-DStress model refines the psychological construct of self-efficacy. To explain and predict the dynamics of self-efficacy and predict individual performance of targeted behaviors, the self-efficacy construct is implemented as a theory-based neurocognitive simulation of the interaction of behavioral goals, memories of past experiences, and behavioral performance.
Navy Enhanced Sierra Mechanics (NESM): Toolbox for predicting Navy shock and damage
Moyer, Thomas; Stergiou, Jonathan; Reese, Garth; ...
2016-05-25
Here, the US Navy is developing a new suite of computational mechanics tools (Navy Enhanced Sierra Mechanics) for the prediction of ship response, damage, and shock environments transmitted to vital systems during threat weapon encounters. NESM includes fully coupled Euler-Lagrange solvers tailored to ship shock/damage predictions. NESM is optimized to support high-performance computing architectures, providing the physics-based ship response/threat weapon damage predictions needed to support the design and assessment of highly survivable ships. NESM is being employed to support current Navy ship design and acquisition programs while being further developed for future Navy fleet needs.
NASA Technical Reports Server (NTRS)
1982-01-01
A FORTRAN coded computer program and method to predict the reaction control fuel consumption statistics for a three axis stabilized rocket vehicle upper stage is described. A Monte Carlo approach is used which is more efficient by using closed form estimates of impulses. The effects of rocket motor thrust misalignment, static unbalance, aerodynamic disturbances, and deviations in trajectory, mass properties and control system characteristics are included. This routine can be applied to many types of on-off reaction controlled vehicles. The pseudorandom number generation and statistical analyses subroutines including the output histograms can be used for other Monte Carlo analyses problems.
NASA Technical Reports Server (NTRS)
Treon, S. L.
1979-01-01
A survey of the U.S. aerospace industry in late 1977 suggests that there will be an increasing use of computer-aided prediction-design technology (CPD Tech) in the aircraft development process but that, overall, only a modest reduction in wind-tunnel test requirements from the current level is expected in the period through 1995. Opinions were received from key spokesmen in 23 of the 26 solicited major companies or corporate divisions involved in the design and manufacture of nonrotary wing aircraft. Development programs for nine types of aircraft related to test phases and wind-tunnel size and speed range were considered.
FHWA Study Tour For European Traffic Monitoring Programs and Technologies
DOT National Transportation Integrated Search
1998-07-01
In March 1998, the Federal Highway Administration (FHWA) released the FHWA Traffic Noise Model [FHWA TNM (registered trademark)], Version 1.0, a state-of-the-art computer program for highway traffic noise prediction and analysis. Comparisons have sho...
NASA Technical Reports Server (NTRS)
Dunbar, D. N.; Tunnah, B. G.
1978-01-01
A FORTRAN computer program is described for predicting the flow streams and material, energy, and economic balances of a typical petroleum refinery, with particular emphasis on production of aviation turbine fuel of varying end point and hydrogen content specifications. The program has provision for shale oil and coal oil in addition to petroleum crudes. A case study feature permits dependent cases to be run for parametric or optimization studies by input of only the variables which are changed from the base case.
NASA Technical Reports Server (NTRS)
Dunbar, D. N.; Tunnah, B. G.
1978-01-01
The FORTRAN computing program predicts flow streams and material, energy, and economic balances of a typical petroleum refinery, with particular emphasis on production of aviation turbine fuels of varying end point and hydrogen content specifications. The program has a provision for shale oil and coal oil in addition to petroleum crudes. A case study feature permits dependent cases to be run for parametric or optimization studies by input of only the variables which are changed from the base case.
NASA Technical Reports Server (NTRS)
Bareiss, L. E.
1978-01-01
The paper presents a compilation of the results of a systems level Shuttle/payload contamination analysis and related computer modeling activities. The current technical assessment of the contamination problems anticipated during the Spacelab program are discussed and recommendations are presented on contamination abatement designs and operational procedures based on experience gained in the field of contamination analysis and assessment, dating back to the pre-Skylab era. The ultimate test of the Shuttle/Payload Contamination Evaluation program will be through comparison of predictions with measured levels of contamination during actual flight.
Analysis of whisker-toughened CMC structural components using an interactive reliability model
NASA Technical Reports Server (NTRS)
Duffy, Stephen F.; Palko, Joseph L.
1992-01-01
Realizing wider utilization of ceramic matrix composites (CMC) requires the development of advanced structural analysis technologies. This article focuses on the use of interactive reliability models to predict component probability of failure. The deterministic William-Warnke failure criterion serves as theoretical basis for the reliability model presented here. The model has been implemented into a test-bed software program. This computer program has been coupled to a general-purpose finite element program. A simple structural problem is presented to illustrate the reliability model and the computer algorithm.
Moments of inclination error distribution computer program
NASA Technical Reports Server (NTRS)
Myler, T. R.
1981-01-01
A FORTRAN coded computer program is described which calculates orbital inclination error statistics using a closed-form solution. This solution uses a data base of trajectory errors from actual flights to predict the orbital inclination error statistics. The Scott flight history data base consists of orbit insertion errors in the trajectory parameters - altitude, velocity, flight path angle, flight azimuth, latitude and longitude. The methods used to generate the error statistics are of general interest since they have other applications. Program theory, user instructions, output definitions, subroutine descriptions and detailed FORTRAN coding information are included.
Designing for aircraft structural crashworthiness
NASA Technical Reports Server (NTRS)
Thomson, R. G.; Caiafa, C.
1981-01-01
This report describes structural aviation crash dynamics research activities being conducted on general aviation aircraft and transport aircraft. The report includes experimental and analytical correlations of load-limiting subfloor and seat configurations tested dynamically in vertical drop tests and in a horizontal sled deceleration facility. Computer predictions using a finite-element nonlinear computer program, DYCAST, of the acceleration time-histories of these innovative seat and subfloor structures are presented. Proposed application of these computer techniques, and the nonlinear lumped mass computer program KRASH, to transport aircraft crash dynamics is discussed. A proposed FAA full-scale crash test of a fully instrumented radio controlled transport airplane is also described.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Hills, Richard G.; Maniaci, David Charles; Naughton, Jonathan W.
2015-09-01
A Verification and Validation (V&V) framework is presented for the development and execution of coordinated modeling and experimental program s to assess the predictive capability of computational models of complex systems through focused, well structured, and formal processes.The elements of the framework are based on established V&V methodology developed by various organizations including the Department of Energy, National Aeronautics and Space Administration, the American Institute of Aeronautics and Astronautics, and the American Society of Mechanical Engineers. Four main topics are addressed: 1) Program planning based on expert elicitation of the modeling physics requirements, 2) experimental design for model assessment, 3)more » uncertainty quantification for experimental observations and computational model simulations, and 4) assessment of the model predictive capability. The audience for this document includes program planners, modelers, experimentalist, V &V specialist, and customers of the modeling results.« less
Wexler, Eliezer J.
1992-01-01
Analytical solutions to the advective-dispersive solute-transport equation are useful in predicting the fate of solutes in ground water. Analytical solutions compiled from available literature or derived by the author are presented for a variety of boundary condition types and solute-source configurations in one-, two-, and three-dimensional systems having uniform ground-water flow. A set of user-oriented computer programs was created to evaluate these solutions and to display the results in tabular and computer-graphics format. These programs incorporate many features that enhance their accuracy, ease of use, and versatility. Documentation for the programs describes their operation and required input data, and presents the results of sample problems. Derivations of selected solutions, source codes for the computer programs, and samples of program input and output also are included.
The computer program SPARC (SPARC Performs Automated Reasoning in Chemistry) has been under development for several years to estimate physical properties and chemical reactivity parameters of organic compounds strictly from molecular structure. SPARC uses computational algorithms...
DOT National Transportation Integrated Search
1976-08-01
This report contains a functional design for the simulation of a future automation concept in support of the ATC Systems Command Center. The simulation subsystem performs airport airborne arrival delay predictions and computes flow control tables for...
MPI_XSTAR: MPI-based Parallelization of the XSTAR Photoionization Program
NASA Astrophysics Data System (ADS)
Danehkar, Ashkbiz; Nowak, Michael A.; Lee, Julia C.; Smith, Randall K.
2018-02-01
We describe a program for the parallel implementation of multiple runs of XSTAR, a photoionization code that is used to predict the physical properties of an ionized gas from its emission and/or absorption lines. The parallelization program, called MPI_XSTAR, has been developed and implemented in the C++ language by using the Message Passing Interface (MPI) protocol, a conventional standard of parallel computing. We have benchmarked parallel multiprocessing executions of XSTAR, using MPI_XSTAR, against a serial execution of XSTAR, in terms of the parallelization speedup and the computing resource efficiency. Our experience indicates that the parallel execution runs significantly faster than the serial execution, however, the efficiency in terms of the computing resource usage decreases with increasing the number of processors used in the parallel computing.
Scout trajectory error propagation computer program
NASA Technical Reports Server (NTRS)
Myler, T. R.
1982-01-01
Since 1969, flight experience has been used as the basis for predicting Scout orbital accuracy. The data used for calculating the accuracy consists of errors in the trajectory parameters (altitude, velocity, etc.) at stage burnout as observed on Scout flights. Approximately 50 sets of errors are used in Monte Carlo analysis to generate error statistics in the trajectory parameters. A covariance matrix is formed which may be propagated in time. The mechanization of this process resulted in computer program Scout Trajectory Error Propagation (STEP) and is described herein. Computer program STEP may be used in conjunction with the Statistical Orbital Analysis Routine to generate accuracy in the orbit parameters (apogee, perigee, inclination, etc.) based upon flight experience.
Thermal and orbital analysis of Earth monitoring Sun-synchronous space experiments
NASA Technical Reports Server (NTRS)
Killough, Brian D.
1990-01-01
The fundamentals of an Earth monitoring Sun-synchronous orbit are presented. A Sun-synchronous Orbit Analysis Program (SOAP) was developed to calculate orbital parameters for an entire year. The output from this program provides the required input data for the TRASYS thermal radiation computer code, which in turn computes the infrared, solar and Earth albedo heat fluxes incident on a space experiment. Direct incident heat fluxes can be used as input to a generalized thermal analyzer program to size radiators and predict instrument operating temperatures. The SOAP computer code and its application to the thermal analysis methodology presented, should prove useful to the thermal engineer during the design phases of Earth monitoring Sun-synchronous space experiments.
NASA Technical Reports Server (NTRS)
Dumbauld, R. K.; Bjorklund, J. R.; Bowers, J. F.
1973-01-01
The NASA/MSFC multilayer diffusion models are discribed which are used in applying meteorological information to the estimation of toxic fuel hazards resulting from the launch of rocket vehicle and from accidental cold spills and leaks of toxic fuels. Background information, definitions of terms, description of the multilayer concept are presented along with formulas for determining the buoyant rise of hot exhaust clouds or plumes from conflagrations, and descriptions of the multilayer diffusion models. A brief description of the computer program is given, and sample problems and their solutions are included. Derivations of the cloud rise formulas, users instructions, and computer program output lists are also included.
NASA Technical Reports Server (NTRS)
Goradia, S. H.; Lilley, D. E.
1975-01-01
Theoretical and experimental studies are described which were conducted for the purpose of developing a new generalized method for the prediction of profile drag of single component airfoil sections with sharp trailing edges. This method aims at solution for the flow in the wake from the airfoil trailing edge to the large distance in the downstream direction; the profile drag of the given airfoil section can then easily be obtained from the momentum balance once the shape of velocity profile at a large distance from the airfoil trailing edge has been computed. Computer program subroutines have been developed for the computation of the profile drag and flow in the airfoil wake on CDC6600 computer. The required inputs to the computer program consist of free stream conditions and the characteristics of the boundary layers at the airfoil trailing edge or at the point of incipient separation in the neighborhood of airfoil trailing edge. The method described is quite generalized and hence can be extended to the solution of the profile drag for multi-component airfoil sections.
Attending to Structural Programming Features Predicts Differences in Learning and Motivation
ERIC Educational Resources Information Center
Witherspoon, Eben B.; Schunn, Christian D.; Higashi, Ross M.; Shoop, Robin
2018-01-01
Educational robotics programs offer an engaging opportunity to potentially teach core computer science concepts and practices in K-12 classrooms. Here, we test the effects of units with different programming content within a virtual robotics context on both learning gains and motivational changes in middle school (6th-8th grade) robotics…
NASA Technical Reports Server (NTRS)
Knauber, R. N.
1982-01-01
A FORTRAN coded computer program which computes the capture transient of a launch vehicle upper stage at the ignition and/or separation event is presented. It is for a single degree-of-freedom on-off reaction jet attitude control system. The Monte Carlo method is used to determine the statistical value of key parameters at the outcome of the event. Aerodynamic and booster induced disturbances, vehicle and control system characteristics, and initial conditions are treated as random variables. By appropriate selection of input data pitch, yaw and roll axes can be analyzed. Transient response of a single deterministic case can be computed. The program is currently set up on a CDC CYBER 175 computer system but is compatible with ANSI FORTRAN computer language. This routine has been used over the past fifteen (15) years for the SCOUT Launch Vehicle and has been run on RECOMP III, IBM 7090, IBM 360/370, CDC6600 and CDC CYBER 175 computers with little modification.
Advanced Simulation & Computing FY15 Implementation Plan Volume 2, Rev. 0.5
DOE Office of Scientific and Technical Information (OSTI.GOV)
McCoy, Michel; Archer, Bill; Matzen, M. Keith
2014-09-16
The Stockpile Stewardship Program (SSP) is a single, highly integrated technical program for maintaining the surety and reliability of the U.S. nuclear stockpile. The SSP uses nuclear test data, computational modeling and simulation, and experimental facilities to advance understanding of nuclear weapons. It includes stockpile surveillance, experimental research, development and engineering programs, and an appropriately scaled production capability to support stockpile requirements. This integrated national program requires the continued use of experimental facilities and programs, and the computational enhancements to support these programs. The Advanced Simulation and Computing Program (ASC) is a cornerstone of the SSP, providing simulation capabilities andmore » computational resources that support annual stockpile assessment and certification, study advanced nuclear weapons design and manufacturing processes, analyze accident scenarios and weapons aging, and provide the tools to enable stockpile Life Extension Programs (LEPs) and the resolution of Significant Finding Investigations (SFIs). This requires a balance of resource, including technical staff, hardware, simulation software, and computer science solutions. As the program approaches the end of its second decade, ASC is intently focused on increasing predictive capabilities in a three-dimensional (3D) simulation environment while maintaining support to the SSP. The program continues to improve its unique tools for solving progressively more difficult stockpile problems (sufficient resolution, dimensionality, and scientific details), quantify critical margins and uncertainties, and resolve increasingly difficult analyses needed for the SSP. Where possible, the program also enables the use of high-performance simulation and computing tools to address broader national security needs, such as foreign nuclear weapon assessments and counternuclear terrorism.« less
NASA Technical Reports Server (NTRS)
Hall, Edward J.; Delaney, Robert A.; Adamczyk, John J.; Miller, Christopher J.; Arnone, Andrea; Swanson, Charles
1993-01-01
The primary objective of this study was the development of a time-marching three-dimensional Euler/Navier-Stokes aerodynamic analysis to predict steady and unsteady compressible transonic flows about ducted and unducted propfan propulsion systems employing multiple blade rows. The computer codes resulting from this study are referred to as ADPAC-AOACR (Advanced Ducted Propfan Analysis Codes-Angle of Attack Coupled Row). This report is intended to serve as a computer program user's manual for the ADPAC-AOACR codes developed under Task 5 of NASA Contract NAS3-25270, Unsteady Counterrotating Ducted Propfan Analysis. The ADPAC-AOACR program is based on a flexible multiple blocked grid discretization scheme permitting coupled 2-D/3-D mesh block solutions with application to a wide variety of geometries. For convenience, several standard mesh block structures are described for turbomachinery applications. Aerodynamic calculations are based on a four-stage Runge-Kutta time-marching finite volume solution technique with added numerical dissipation. Steady flow predictions are accelerated by a multigrid procedure. Numerical calculations are compared with experimental data for several test cases to demonstrate the utility of this approach for predicting the aerodynamics of modern turbomachinery configurations employing multiple blade rows.
Predictor - Predictive Reaction Design via Informatics, Computation and Theories of Reactivity
2017-10-10
into more complex and valuable molecules, but are limited by: 1. The extensive time it takes to design and optimize a synthesis 2. Multi-step...system. As it is fully compatible to the industry standard SQL, designing a server- based system at a later time will be trivial. Producing a JAVA front...Report: PREDICTOR - Predictive REaction Design via Informatics, Computation and Theories of Reactivity The goal of this program was to create a cyber
1980-01-01
SUPPLEMENTARY NOTES Is. KEY WORDS (Continue on reverse ede If neceseay id Identify by block number) Carbon Monoxide (CO) Computer Program Carboxyhemoglobin ...several researchers, which predicts the instantaneous amount of carboxyhemoglobin (COHb) in the blood of a person based upon the amount of carbon monoxide...developed from an empirical equation (derived from reference I and detailed in reference 3) which predicts the amount of carboxyhemoglobin (COHb) in
Documentation of the data analysis system for the gamma ray monitor aboard OSO-H
NASA Technical Reports Server (NTRS)
Croteau, S.; Buck, A.; Higbie, P.; Kantauskis, J.; Foss, S.; Chupp, D.; Forrest, D. J.; Suri, A.; Gleske, I.
1973-01-01
The programming system is presented which was developed to prepare the data from the gamma ray monitor on OSO-7 for scientific analysis. The detector, data, and objectives are described in detail. Programs presented include; FEEDER, PASS-1, CAL1, CAL2, PASS-3, Van Allen Belt Predict Program, Computation Center Plot Routine, and Response Function Programs.
BEHAVE: fire behavior prediction and fuel modeling system - BURN subsystem, Part 2
Patricia L. Andrews; Carolyn H. Chase
1989-01-01
This is the third publication describing the BEHAVE system of computer programs for predicting behavior of wildland fires. This publication adds the following predictive capabilities: distance firebrands are lofted ahead of a wind-driven surface fire, probabilities of firebrands igniting spot fires, scorch height of trees, and percentage of tree mortality. The system...
Predicting Aircraft Spray Patterns on Crops
NASA Technical Reports Server (NTRS)
Teske, M. E.; Bilanin, A. J.
1986-01-01
Agricultural Dispersion Prediction (AGDISP) system developed to predict deposition of agricultural material released from rotary- and fixed-wing aircraft. AGDISP computes ensemble average mean motion resulting from turbulent fluid fluctuations. Used to examine ways of making dispersal process more efficient by insuring uniformity, reducing waste, and saving money. Programs in AGDISP system written in FORTRAN IV for interactive execution.
Bellows flow-induced vibrations
NASA Technical Reports Server (NTRS)
Tygielski, P. J.; Smyly, H. M.; Gerlach, C. R.
1983-01-01
The bellows flow excitation mechanism and results of comprehensive test program are summarized. The analytical model for predicting bellows flow induced stress is refined. The model includes the effects of an upstream elbow, arbitrary geometry, and multiple piles. A refined computer code for predicting flow induced stress is described which allows life prediction if a material S-N diagram is available.
A unified approach for composite cost reporting and prediction in the ACT program
NASA Technical Reports Server (NTRS)
Freeman, W. Tom; Vosteen, Louis F.; Siddiqi, Shahid
1991-01-01
The Structures Technology Program Office (STPO) at NASA Langley Research Center has held two workshops with representatives from the commercial airframe companies to establish a plan for development of a standard cost reporting format and a cost prediction tool for conceptual and preliminary designers. This paper reviews the findings of the workshop representatives with a plan for implementation of their recommendations. The recommendations of the cost tracking and reporting committee will be implemented by reinstituting the collection of composite part fabrication data in a format similar to the DoD/NASA Structural Composites Fabrication Guide. The process of data collection will be automated by taking advantage of current technology with user friendly computer interfaces and electronic data transmission. Development of a conceptual and preliminary designers' cost prediction model will be initiated. The model will provide a technically sound method for evaluating the relative cost of different composite structural designs, fabrication processes, and assembly methods that can be compared to equivalent metallic parts or assemblies. The feasibility of developing cost prediction software in a modular form for interfacing with state of the art preliminary design tools and computer aided design (CAD) programs is assessed.
Free energy minimization to predict RNA secondary structures and computational RNA design.
Churkin, Alexander; Weinbrand, Lina; Barash, Danny
2015-01-01
Determining the RNA secondary structure from sequence data by computational predictions is a long-standing problem. Its solution has been approached in two distinctive ways. If a multiple sequence alignment of a collection of homologous sequences is available, the comparative method uses phylogeny to determine conserved base pairs that are more likely to form as a result of billions of years of evolution than by chance. In the case of single sequences, recursive algorithms that compute free energy structures by using empirically derived energy parameters have been developed. This latter approach of RNA folding prediction by energy minimization is widely used to predict RNA secondary structure from sequence. For a significant number of RNA molecules, the secondary structure of the RNA molecule is indicative of its function and its computational prediction by minimizing its free energy is important for its functional analysis. A general method for free energy minimization to predict RNA secondary structures is dynamic programming, although other optimization methods have been developed as well along with empirically derived energy parameters. In this chapter, we introduce and illustrate by examples the approach of free energy minimization to predict RNA secondary structures.
Algorithms and Parametric Studies for Assessing Effects of Two-Point Contact
DOT National Transportation Integrated Search
1984-02-01
This report describes analyses conducted to assess the effects of two-point wheel rail contact on a single wheel on the prediction of wheel-rail forces, and for including these effects in a computer program for predicting curving behavior of rail veh...
Acoustic loads prediction on jet aircraft
NASA Technical Reports Server (NTRS)
Reddy, N. N.
1992-01-01
A nearfield aircraft noise prediction computer program is presented for the F-22 aircraft. The dominant sources of noise are jet turbulent mixing noise, jet broadband shock noise, and fluctuating pressure under the turbulent boundary layer. All results from this investigation are presented in viewgraph format.
Acoustic loads prediction on jet aircraft
NASA Astrophysics Data System (ADS)
Reddy, N. N.
1992-07-01
A nearfield aircraft noise prediction computer program is presented for the F-22 aircraft. The dominant sources of noise are jet turbulent mixing noise, jet broadband shock noise, and fluctuating pressure under the turbulent boundary layer. All results from this investigation are presented in viewgraph format.
Automatic gender detection of dream reports: A promising approach.
Wong, Christina; Amini, Reza; De Koninck, Joseph
2016-08-01
A computer program was developed in an attempt to differentiate the dreams of males from females. Hypothesized gender predictors were based on previous literature concerning both dream content and written language features. Dream reports from home-collected dream diaries of 100 male (144 dreams) and 100 female (144 dreams) adolescent Anglophones were matched for equal length. They were first scored with the Hall and Van de Castle (HVDC) scales and quantified using DreamSAT. Two male and two female undergraduate students were asked to read all dreams and predict the dreamer's gender. They averaged a pairwise percent correct gender prediction of 75.8% (κ=0.516), while the Automatic Analysis showed that the computer program's accuracy was 74.5% (κ=0.492), both of which were higher than chance of 50% (κ=0.00). The prediction levels were maintained when dreams containing obvious gender identifiers were eliminated and integration of HVDC scales did not improve prediction. Copyright © 2016 Elsevier Inc. All rights reserved.
XTALOPT: An open-source evolutionary algorithm for crystal structure prediction
NASA Astrophysics Data System (ADS)
Lonie, David C.; Zurek, Eva
2011-02-01
The implementation and testing of XTALOPT, an evolutionary algorithm for crystal structure prediction, is outlined. We present our new periodic displacement (ripple) operator which is ideally suited to extended systems. It is demonstrated that hybrid operators, which combine two pure operators, reduce the number of duplicate structures in the search. This allows for better exploration of the potential energy surface of the system in question, while simultaneously zooming in on the most promising regions. A continuous workflow, which makes better use of computational resources as compared to traditional generation based algorithms, is employed. Various parameters in XTALOPT are optimized using a novel benchmarking scheme. XTALOPT is available under the GNU Public License, has been interfaced with various codes commonly used to study extended systems, and has an easy to use, intuitive graphical interface. Program summaryProgram title:XTALOPT Catalogue identifier: AEGX_v1_0 Program summary URL:http://cpc.cs.qub.ac.uk/summaries/AEGX_v1_0.html Program obtainable from: CPC Program Library, Queen's University, Belfast, N. Ireland Licensing provisions: GPL v2.1 or later [1] No. of lines in distributed program, including test data, etc.: 36 849 No. of bytes in distributed program, including test data, etc.: 1 149 399 Distribution format: tar.gz Programming language: C++ Computer: PCs, workstations, or clusters Operating system: Linux Classification: 7.7 External routines: QT [2], OpenBabel [3], AVOGADRO [4], SPGLIB [8] and one of: VASP [5], PWSCF [6], GULP [7]. Nature of problem: Predicting the crystal structure of a system from its stoichiometry alone remains a grand challenge in computational materials science, chemistry, and physics. Solution method: Evolutionary algorithms are stochastic search techniques which use concepts from biological evolution in order to locate the global minimum on their potential energy surface. Our evolutionary algorithm, XTALOPT, is freely available to the scientific community for use and collaboration under the GNU Public License. Running time: User dependent. The program runs until stopped by the user.
Turbine Blade and Endwall Heat Transfer Measured in NASA Glenn's Transonic Turbine Blade Cascade
NASA Technical Reports Server (NTRS)
Giel, Paul W.
2000-01-01
Higher operating temperatures increase the efficiency of aircraft gas turbine engines, but can also degrade internal components. High-pressure turbine blades just downstream of the combustor are particularly susceptible to overheating. Computational fluid dynamics (CFD) computer programs can predict the flow around the blades so that potential hot spots can be identified and appropriate cooling schemes can be designed. Various blade and cooling schemes can be examined computationally before any hardware is built, thus saving time and effort. Often though, the accuracy of these programs has been found to be inadequate for predicting heat transfer. Code and model developers need highly detailed aerodynamic and heat transfer data to validate and improve their analyses. The Transonic Turbine Blade Cascade was built at the NASA Glenn Research Center at Lewis Field to help satisfy the need for this type of data.
Operation of the computer model for microenvironment solar exposure
NASA Technical Reports Server (NTRS)
Gillis, J. R.; Bourassa, R. J.; Gruenbaum, P. E.
1995-01-01
A computer model for microenvironmental solar exposure was developed to predict solar exposure to satellite surfaces which may shadow or reflect on one another. This document describes the technical features of the model as well as instructions for the installation and use of the program.
Composite Nanomechanics: A Mechanistic Properties Prediction
NASA Technical Reports Server (NTRS)
Chamis, Christos C.; Handler, Louis M.; Manderscheid, Jane M.
2007-01-01
A unique mechanistic theory is described to predict the properties of nanocomposites. The theory is based on composite micromechanics with progressive substructuring down to a nanoscale slice of a nanofiber where all the governing equations are formulated. These equations hav e been programmed in a computer code. That computer code is used to predict 25 properties of a mononanofiber laminate. The results are pr esented graphically and discussed with respect to their practical sig nificance. Most of the results show smooth distributions. Results for matrix-dependent properties show bimodal through-the-thickness distr ibution with discontinuous changes from mode to mode.
Progressive damage, fracture predictions and post mortem correlations for fiber composites
NASA Technical Reports Server (NTRS)
1985-01-01
Lewis Research Center is involved in the development of computational mechanics methods for predicting the structural behavior and response of composite structures. In conjunction with the analytical methods development, experimental programs including post failure examination are conducted to study various factors affecting composite fracture such as laminate thickness effects, ply configuration, and notch sensitivity. Results indicate that the analytical capabilities incorporated in the CODSTRAN computer code are effective in predicting the progressive damage and fracture of composite structures. In addition, the results being generated are establishing a data base which will aid in the characterization of composite fracture.
Computer program for Stirling engine performance calculations
NASA Technical Reports Server (NTRS)
Tew, R. C., Jr.
1983-01-01
The thermodynamic characteristics of the Stirling engine were analyzed and modeled on a computer to support its development as a possible alternative to the automobile spark ignition engine. The computer model is documented. The documentation includes a user's manual, symbols list, a test case, comparison of model predictions with test results, and a description of the analytical equations used in the model.
NASA Technical Reports Server (NTRS)
Dang, Anthony; Nickerson, Gary R.
1987-01-01
For the development of a Heavy Lift Launch Vehicle (HLLV) several engines with different operating cycles and using LOX/Hydrocarbon propellants are presently being examined. Some concepts utilize hydrogen for thrust chamber wall cooling followed by a gas generator turbine drive cycle with subsequent dumping of H2/O2 combustion products into the nozzle downstream of the throat. In the Space Transportation Booster Engine (STBE) selection process the specific impulse will be one of the optimization criteria; however, the current performance prediction programs do not have the capability to include a third propellant in this process, nor to account for the effect of dumping the gas-generator product tangentially inside the nozzle. The purpose is to describe a computer program for accurately predicting the performance of such an engine. The code consists of two modules; one for the inviscid performance, and the other for the viscous loss. For the first module, the two-dimensional kinetics program (TDK) was modified to account for tripropellant chemistry, and for the effect of tangential slot injection. For the viscous loss, the Mass Addition Boundary Layer program (MABL) was modified to include the effects of the boundary layer-shear layer interaction, and tripropellant chemistry. Calculations were made for a real engine and compared with available data.
NASA Technical Reports Server (NTRS)
Cake, J. E.; Regetz, J. D., Jr.
1975-01-01
A method is presented for open loop guidance of a solar electric propulsion spacecraft to geosynchronous orbit. The method consists of determining the thrust vector profiles on the ground with an optimization computer program, and performing updates based on the difference between the actual trajectory and that predicted with a precision simulation computer program. The motivation for performing the guidance analysis during the mission planning phase is discussed, and a spacecraft design option that employs attitude orientation constraints is presented. The improvements required in both the optimization program and simulation program are set forth, together with the efforts to integrate the programs into the ground support software for the guidance system.
NASA Technical Reports Server (NTRS)
Cake, J. E.; Regetz, J. D., Jr.
1975-01-01
A method is presented for open loop guidance of a solar electric propulsion spacecraft to geosynchronsus orbit. The method consists of determining the thrust vector profiles on the ground with an optimization computer program, and performing updates based on the difference between the actual trajectory and that predicted with a precision simulation computer program. The motivation for performing the guidance analysis during the mission planning phase is discussed, and a spacecraft design option that employs attitude orientation constraints is presented. The improvements required in both the optimization program and simulation program are set forth, together with the efforts to integrate the programs into the ground support software for the guidance system.
Combining Thermal And Structural Analyses
NASA Technical Reports Server (NTRS)
Winegar, Steven R.
1990-01-01
Computer code makes programs compatible so stresses and deformations calculated. Paper describes computer code combining thermal analysis with structural analysis. Called SNIP (for SINDA-NASTRAN Interfacing Program), code provides interface between finite-difference thermal model of system and finite-element structural model when no node-to-element correlation between models. Eliminates much manual work in converting temperature results of SINDA (Systems Improved Numerical Differencing Analyzer) program into thermal loads for NASTRAN (NASA Structural Analysis) program. Used to analyze concentrating reflectors for solar generation of electric power. Large thermal and structural models needed to predict distortion of surface shapes, and SNIP saves considerable time and effort in combining models.
Wing Leading Edge RCC Rapid Response Damage Prediction Tool (IMPACT2)
NASA Technical Reports Server (NTRS)
Clark, Robert; Cottter, Paul; Michalopoulos, Constantine
2013-01-01
This rapid response computer program predicts Orbiter Wing Leading Edge (WLE) damage caused by ice or foam impact during a Space Shuttle launch (Program "IMPACT2"). The program was developed after the Columbia accident in order to assess quickly WLE damage due to ice, foam, or metal impact (if any) during a Shuttle launch. IMPACT2 simulates an impact event in a few minutes for foam impactors, and in seconds for ice and metal impactors. The damage criterion is derived from results obtained from one sophisticated commercial program, which requires hours to carry out simulations of the same impact events. The program was designed to run much faster than the commercial program with prediction of projectile threshold velocities within 10 to 15% of commercial-program values. The mathematical model involves coupling of Orbiter wing normal modes of vibration to nonlinear or linear springmass models. IMPACT2 solves nonlinear or linear impact problems using classical normal modes of vibration of a target, and nonlinear/ linear time-domain equations for the projectile. Impact loads and stresses developed in the target are computed as functions of time. This model is novel because of its speed of execution. A typical model of foam, or other projectile characterized by material nonlinearities, impacting an RCC panel is executed in minutes instead of hours needed by the commercial programs. Target damage due to impact can be assessed quickly, provided that target vibration modes and allowable stress are known.
NASA Astrophysics Data System (ADS)
Johnston, Michael A.; Farrell, Damien; Nielsen, Jens Erik
2012-04-01
The exchange of information between experimentalists and theoreticians is crucial to improving the predictive ability of theoretical methods and hence our understanding of the related biology. However many barriers exist which prevent the flow of information between the two disciplines. Enabling effective collaboration requires that experimentalists can easily apply computational tools to their data, share their data with theoreticians, and that both the experimental data and computational results are accessible to the wider community. We present a prototype collaborative environment for developing and validating predictive tools for protein biophysical characteristics. The environment is built on two central components; a new python-based integration module which allows theoreticians to provide and manage remote access to their programs; and PEATDB, a program for storing and sharing experimental data from protein biophysical characterisation studies. We demonstrate our approach by integrating PEATSA, a web-based service for predicting changes in protein biophysical characteristics, into PEATDB. Furthermore, we illustrate how the resulting environment aids method development using the Potapov dataset of experimentally measured ΔΔGfold values, previously employed to validate and train protein stability prediction algorithms.
NASA Technical Reports Server (NTRS)
Rule, W. K.; Giridharan, V.
1991-01-01
A family of user-friendly, DOS PC based, Microsoft BASIC programs written to provide spacecraft designers with empirical predictions of space debris damage to orbiting spacecraft are described. Spacecraft wall temperatures and condensate formation is also predicted. The spacecraft wall configuration is assumed to consist of multilayered insulation (MLI) placed between a Whipple style bumper and the pressure wall. Impact damage predictions are based on data sets of experimental results obtained from simulating debris impacts on spacecraft using light gas guns on earth. A module of the program facilitates the creation of the database of experimental results that is used by the damage prediction modules to predict damage to the bumper, the MLI, and the pressure wall. A finite difference technique is used to predict temperature distributions in the pressure wall, the MLI, and the bumper. Condensate layer thickness is predicted for the case where the pressure wall temperature drops below the dew point temperature of the spacecraft atmosphere.
User's manual for the REEDM (Rocket Exhaust Effluent Diffusion Model) computer program
NASA Technical Reports Server (NTRS)
Bjorklund, J. R.; Dumbauld, R. K.; Cheney, C. S.; Geary, H. V.
1982-01-01
The REEDM computer program predicts concentrations, dosages, and depositions downwind from normal and abnormal launches of rocket vehicles at NASA's Kennedy Space Center. The atmospheric dispersion models, cloud-rise models, and other formulas used in the REEDM model are described mathematically Vehicle and source parameters, other pertinent physical properties of the rocket exhaust cloud, and meteorological layering techniques are presented as well as user's instructions for REEDM. Worked example problems are included.
NASA Technical Reports Server (NTRS)
Hall, G. F.
1975-01-01
A numerical analysis was developed to determine the airloads on helicopter rotors operating under near-hovering flight conditions capable of producing impulsive noise. A computer program was written in which the solutions for the rotor tip vortex geometry, inflow, aeroelastic response, and airloads are solved in a coupled manner at sequential time steps, with or without the influence of an imposed steady ambient wind or transient gust. The program was developed for future applications in which predicted airloads would be incorporated in an acoustics analysis to attempt to predict and analyze impulsive noise (blade slap). The analysis was applied to a hovering full-scale rotor for which impulsive noise was recorded in the presence of ambient wind. The predicted tip vortex coordinates are in reasonable agreement with the test data, and the blade airload solutions converged to a periodic behavior for an imposed steady ambient wind conditions.
Prediction of elemental creep. [steady state and cyclic data from regression analysis
NASA Technical Reports Server (NTRS)
Davis, J. W.; Rummler, D. R.
1975-01-01
Cyclic and steady-state creep tests were performed to provide data which were used to develop predictive equations. These equations, describing creep as a function of stress, temperature, and time, were developed through the use of a least squares regression analyses computer program for both the steady-state and cyclic data sets. Comparison of the data from the two types of tests, revealed that there was no significant difference between the cyclic and steady-state creep strains for the L-605 sheet under the experimental conditions investigated (for the same total time at load). Attempts to develop a single linear equation describing the combined steady-state and cyclic creep data resulted in standard errors of estimates higher than obtained for the individual data sets. A proposed approach to predict elemental creep in metals uses the cyclic creep equation and a computer program which applies strain and time hardening theories of creep accumulation.
NASA Technical Reports Server (NTRS)
Coen, Peter G.
1991-01-01
A new computer technique for the analysis of transport aircraft sonic boom signature characteristics was developed. This new technique, based on linear theory methods, combines the previously separate equivalent area and F function development with a signature propagation method using a single geometry description. The new technique was implemented in a stand-alone computer program and was incorporated into an aircraft performance analysis program. Through these implementations, both configuration designers and performance analysts are given new capabilities to rapidly analyze an aircraft's sonic boom characteristics throughout the flight envelope.
NASA Technical Reports Server (NTRS)
Kontos, Karen B.; Kraft, Robert E.; Gliebe, Philip R.
1996-01-01
The Aircraft Noise Predication Program (ANOPP) is an industry-wide tool used to predict turbofan engine flyover noise in system noise optimization studies. Its goal is to provide the best currently available methods for source noise prediction. As part of a program to improve the Heidmann fan noise model, models for fan inlet and fan exhaust noise suppression estimation that are based on simple engine and acoustic geometry inputs have been developed. The models can be used to predict sound power level suppression and sound pressure level suppression at a position specified relative to the engine inlet.
Light aircraft lift, drag, and moment prediction: A review and analysis
NASA Technical Reports Server (NTRS)
Smetana, F. O.; Summey, D. C.; Smith, N. S.; Carden, R. K.
1975-01-01
The historical development of analytical methods for predicting the lift, drag, and pitching moment of complete light aircraft configurations in cruising flight is reviewed. Theoretical methods, based in part on techniques described in the literature and in part on original work, are developed. These methods form the basis for understanding the computer programs given to: (1) compute the lift, drag, and moment of conventional airfoils, (2) extend these two-dimensional characteristics to three dimensions for moderate-to-high aspect ratio unswept wings, (3) plot complete configurations, (4) convert the fuselage geometric data to the correct input format, (5) compute the fuselage lift and drag, (6) compute the lift and moment of symmetrical airfoils to M = 1.0 by a simplified semi-empirical procedure, and (7) compute, in closed form, the pressure distribution over a prolate spheroid at alpha = 0. Comparisons of the predictions with experiment indicate excellent lift and drag agreement for conventional airfoils and wings. Limited comparisons of body-alone drag characteristics yield reasonable agreement. Also included are discussions for interference effects and techniques for summing the results above to obtain predictions for complete configurations.
Toward Agent Programs with Circuit Semantics
NASA Technical Reports Server (NTRS)
Nilsson, Nils J.
1992-01-01
New ideas are presented for computing and organizing actions for autonomous agents in dynamic environments-environments in which the agent's current situation cannot always be accurately discerned and in which the effects of actions cannot always be reliably predicted. The notion of 'circuit semantics' for programs based on 'teleo-reactive trees' is introduced. Program execution builds a combinational circuit which receives sensory inputs and controls actions. These formalisms embody a high degree of inherent conditionality and thus yield programs that are suitably reactive to their environments. At the same time, the actions computed by the programs are guided by the overall goals of the agent. The paper also speculates about how programs using these ideas could be automatically generated by artificial intelligence planning systems and adapted by learning methods.
Lattice-free prediction of three-dimensional structure of programmed DNA assemblies
Pan, Keyao; Kim, Do-Nyun; Zhang, Fei; Adendorff, Matthew R.; Yan, Hao; Bathe, Mark
2014-01-01
DNA can be programmed to self-assemble into high molecular weight 3D assemblies with precise nanometer-scale structural features. Although numerous sequence design strategies exist to realize these assemblies in solution, there is currently no computational framework to predict their 3D structures on the basis of programmed underlying multi-way junction topologies constrained by DNA duplexes. Here, we introduce such an approach and apply it to assemblies designed using the canonical immobile four-way junction. The procedure is used to predict the 3D structure of high molecular weight planar and spherical ring-like origami objects, a tile-based sheet-like ribbon, and a 3D crystalline tensegrity motif, in quantitative agreement with experiments. Our framework provides a new approach to predict programmed nucleic acid 3D structure on the basis of prescribed secondary structure motifs, with possible application to the design of such assemblies for use in biomolecular and materials science. PMID:25470497
Prediction of V/STOL Noise for Application to Community Noise Exposure
DOT National Transportation Integrated Search
1973-05-01
A computer program to predict the Effective Perceived Noise Level (EPNL), the tone corrected Perceived Noise Level (PNLT) and the A-Weighted Sound Level (dBA) radiated by a V/STOL vehicle as it flies along a prescribed takeoff, landing, or cruise fli...
A Pulsatile Cardiovascular Computer Model for Teaching Heart-Blood Vessel Interaction.
ERIC Educational Resources Information Center
Campbell, Kenneth; And Others
1982-01-01
Describes a model which gives realistic predictions of pulsatile pressure, flow, and volume events in the cardiovascular system. Includes computer oriented laboratory exercises for veterinary and graduate students; equations of the dynamic and algebraic models; and a flow chart for the cardiovascular teaching program. (JN)
In its Computational Toxicology Program, EPA/ORD proposes to integrate genomics and computational methods to provide a mechanistic basis for the prediction of toxicity of chemicals and the pathogenicity of microorganisms. The goal of microbiological water testing is to be able to...
G-LoSA for Prediction of Protein-Ligand Binding Sites and Structures.
Lee, Hui Sun; Im, Wonpil
2017-01-01
Recent advances in high-throughput structure determination and computational protein structure prediction have significantly enriched the universe of protein structure. However, there is still a large gap between the number of available protein structures and that of proteins with annotated function in high accuracy. Computational structure-based protein function prediction has emerged to reduce this knowledge gap. The identification of a ligand binding site and its structure is critical to the determination of a protein's molecular function. We present a computational methodology for predicting small molecule ligand binding site and ligand structure using G-LoSA, our protein local structure alignment and similarity measurement tool. All the computational procedures described here can be easily implemented using G-LoSA Toolkit, a package of standalone software programs and preprocessed PDB structure libraries. G-LoSA and G-LoSA Toolkit are freely available to academic users at http://compbio.lehigh.edu/GLoSA . We also illustrate a case study to show the potential of our template-based approach harnessing G-LoSA for protein function prediction.
Computational methods for a three-dimensional model of the petroleum-discovery process
Schuenemeyer, J.H.; Bawiec, W.J.; Drew, L.J.
1980-01-01
A discovery-process model devised by Drew, Schuenemeyer, and Root can be used to predict the amount of petroleum to be discovered in a basin from some future level of exploratory effort: the predictions are based on historical drilling and discovery data. Because marginal costs of discovery and production are a function of field size, the model can be used to make estimates of future discoveries within deposit size classes. The modeling approach is a geometric one in which the area searched is a function of the size and shape of the targets being sought. A high correlation is assumed between the surface-projection area of the fields and the volume of petroleum. To predict how much oil remains to be found, the area searched must be computed, and the basin size and discovery efficiency must be estimated. The basin is assumed to be explored randomly rather than by pattern drilling. The model may be used to compute independent estimates of future oil at different depth intervals for a play involving multiple producing horizons. We have written FORTRAN computer programs that are used with Drew, Schuenemeyer, and Root's model to merge the discovery and drilling information and perform the necessary computations to estimate undiscovered petroleum. These program may be modified easily for the estimation of remaining quantities of commodities other than petroleum. ?? 1980.
Wexler, Eliezer J.
1989-01-01
Analytical solutions to the advective-dispersive solute-transport equation are useful in predicting the fate of solutes in ground water. Analytical solutions compiled from available literature or derived by the author are presented in this report for a variety of boundary condition types and solute-source configurations in one-, two-, and three-dimensional systems with uniform ground-water flow. A set of user-oriented computer programs was created to evaluate these solutions and to display the results in tabular and computer-graphics format. These programs incorporate many features that enhance their accuracy, ease of use, and versatility. Documentation for the programs describes their operation and required input data, and presents the results of sample problems. Derivations of select solutions, source codes for the computer programs, and samples of program input and output also are included.
Skylab extravehicular mobility unit thermal simulator
NASA Technical Reports Server (NTRS)
Hixon, C. W.; Phillips, M. A.
1974-01-01
The analytical methods, thermal model, and user's instructions for the Skylab Extravehicular Mobility Unit (SEMU) routine are presented. This digital computer program was developed for detailed thermal performance predictions of the SEMU on the NASA-JSC Univac 1108 computer system. It accounts for conductive, convective, and radiant heat transfer as well as fluid flow and special component characterization. The program provides thermal performance predictions for a 967 node thermal model in one thirty-sixth (1/36) of mission time when operated at a calculating interval of three minutes (mission time). The program has the operational flexibility to: (1) accept card or magnetic tape data input for the thermal model describing the SEMU structure, fluid systems, crewman and component performance, (2) accept card and/or magnetic tape input of internally generated heat and heat influx from the space environment, and (3) output tabular or plotted histories of temperature, flow rates, and other parameters describing system operating modes.
Correlation of predicted and measured thermal stresses on a truss-type aircraft structure
NASA Technical Reports Server (NTRS)
Jenkins, J. M.; Schuster, L. S.; Carter, A. L.
1978-01-01
A test structure representing a portion of a hypersonic vehicle was instrumented with strain gages and thermocouples. This test structure was then subjected to laboratory heating representative of supersonic and hypersonic flight conditions. A finite element computer model of this structure was developed using several types of elements with the NASA structural analysis (NASTRAN) computer program. Temperature inputs from the test were used to generate predicted model thermal stresses and these were correlated with the test measurements.
Eddy Viscosity for Variable Density Coflowing Streams,
EDDY CURRENTS, *JET MIXING FLOW, *VISCOSITY, *AIR FLOW, MATHEMATICAL MODELS, INCOMPRESSIBLE FLOW, AXISYMMETRIC FLOW, MATHEMATICAL PREDICTION, THRUST AUGMENTATION , EJECTORS , COMPUTER PROGRAMMING, SECONDARY FLOW, DENSITY, MODIFICATION.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Deline, C.
Computer modeling is able to predict the performance of distributed power electronics (microinverters, power optimizers) in PV systems. However, details about partial shade and other mismatch must be known in order to give the model accurate information to go on. This talk will describe recent updates in NREL’s System Advisor Model program to model partial shading losses with and without distributed power electronics, along with experimental validation results. Computer modeling is able to predict the performance of distributed power electronics (microinverters, power optimizers) in PV systems. However, details about partial shade and other mismatch must be known in order tomore » give the model accurate information to go on. This talk will describe recent updates in NREL’s System Advisor Model program to model partial shading losses.« less
CARES/LIFE Ceramics Analysis and Reliability Evaluation of Structures Life Prediction Program
NASA Technical Reports Server (NTRS)
Nemeth, Noel N.; Powers, Lynn M.; Janosik, Lesley A.; Gyekenyesi, John P.
2003-01-01
This manual describes the Ceramics Analysis and Reliability Evaluation of Structures Life Prediction (CARES/LIFE) computer program. The program calculates the time-dependent reliability of monolithic ceramic components subjected to thermomechanical and/or proof test loading. CARES/LIFE is an extension of the CARES (Ceramic Analysis and Reliability Evaluation of Structures) computer program. The program uses results from MSC/NASTRAN, ABAQUS, and ANSYS finite element analysis programs to evaluate component reliability due to inherent surface and/or volume type flaws. CARES/LIFE accounts for the phenomenon of subcritical crack growth (SCG) by utilizing the power law, Paris law, or Walker law. The two-parameter Weibull cumulative distribution function is used to characterize the variation in component strength. The effects of multiaxial stresses are modeled by using either the principle of independent action (PIA), the Weibull normal stress averaging method (NSA), or the Batdorf theory. Inert strength and fatigue parameters are estimated from rupture strength data of naturally flawed specimens loaded in static, dynamic, or cyclic fatigue. The probabilistic time-dependent theories used in CARES/LIFE, along with the input and output for CARES/LIFE, are described. Example problems to demonstrate various features of the program are also included.
BIOPEP database and other programs for processing bioactive peptide sequences.
Minkiewicz, Piotr; Dziuba, Jerzy; Iwaniak, Anna; Dziuba, Marta; Darewicz, Małgorzata
2008-01-01
This review presents the potential for application of computational tools in peptide science based on a sample BIOPEP database and program as well as other programs and databases available via the World Wide Web. The BIOPEP application contains a database of biologically active peptide sequences and a program enabling construction of profiles of the potential biological activity of protein fragments, calculation of quantitative descriptors as measures of the value of proteins as potential precursors of bioactive peptides, and prediction of bonds susceptible to hydrolysis by endopeptidases in a protein chain. Other bioactive and allergenic peptide sequence databases are also presented. Programs enabling the construction of binary and multiple alignments between peptide sequences, the construction of sequence motifs attributed to a given type of bioactivity, searching for potential precursors of bioactive peptides, and the prediction of sites susceptible to proteolytic cleavage in protein chains are available via the Internet as are other approaches concerning secondary structure prediction and calculation of physicochemical features based on amino acid sequence. Programs for prediction of allergenic and toxic properties have also been developed. This review explores the possibilities of cooperation between various programs.
NASA Technical Reports Server (NTRS)
Saltsman, J. F.
1994-01-01
TS-SRP/PACK is a set of computer programs for characterizing and predicting fatigue and creep-fatigue resistance of metallic materials in the high-temperature, long-life regime for isothermal and nonisothermal fatigue. The programs use the total strain version of the Strainrange Partitioning (TS-SRP). The user should be thoroughly familiar with the TS-SRP method before attempting to use any of these programs. The document for this program includes a theory manual as well as a detailed user's manual with a tutorial to guide the user in the proper use of TS-SRP. An extensive database has also been developed in a parallel effort. This database is an excellent source of high-temperature, creep-fatigue test data and can be used with other life-prediction methods as well. Five programs are included in TS-SRP/PACK along with the alloy database. The TABLE program is used to print the datasets, which are in NAMELIST format, in a reader friendly format. INDATA is used to create new datasets or add to existing ones. The FAIL program is used to characterize the failure behavior of an alloy as given by the constants in the strainrange-life relations used by the total strain version of SRP (TS-SRP) and the inelastic strainrange-based version of SRP. The program FLOW is used to characterize the flow behavior (the constitutive response) of an alloy as given by the constants in the flow equations used by TS-SRP. Finally, LIFE is used to predict the life of a specified cycle, using the constants characterizing failure and flow behavior determined by FAIL and FLOW. LIFE is written in interpretive BASIC to avoid compiling and linking every time the equation constants are changed. Four out of five programs in this package are written in FORTRAN 77 for IBM PC series and compatible computers running MS-DOS and are designed to read data using the NAMELIST format statement. The fifth is written in BASIC version 3.0 for IBM PC series and compatible computers running MS-DOS version 3.10. The executables require at least 239K of memory and DOS 3.1 or higher. To compile the source, a Lahey FORTRAN compiler is required. Source code modifications will be necessary if the compiler to be used does not support NAMELIST input. Probably the easiest revision to make is to use a list-directed READ statement. The standard distribution medium for this program is a set of two 5.25 inch 360K MS-DOS format diskettes. The contents of the diskettes are compressed using the PKWARE archiving tools. The utility to unarchive the files, PKUNZIP.EXE, is included. TS-SRP/PACK was developed in 1992.
User's guide to STIPPAN: A panel method program for slotted tunnel interference prediction
NASA Technical Reports Server (NTRS)
Kemp, W. B., Jr.
1985-01-01
Guidelines are presented for use of the computer program STIPPAN to simulate the subsonic flow in a slotted wind tunnel test section with a known model disturbance. Input data requirements are defined in detail and other aspects of the program usage are discussed in more general terms. The program is written for use in a CDC CYBER 200 class vector processing system.
T.Z. Ye; K.J.S. Jayawickrama; G.R. Johnson
2004-01-01
BLUP (Best linear unbiased prediction) method has been widely used in forest tree improvement programs. Since one of the properties of BLUP is that related individuals contribute to the predictions of each other, it seems logical that integrating data from all generations and from all populations would improve both the precision and accuracy in predicting genetic...
NASA Technical Reports Server (NTRS)
Kraft, R. E.
1996-01-01
A computational method to predict modal reflection coefficients in cylindrical ducts has been developed based on the work of Homicz, Lordi, and Rehm, which uses the Wiener-Hopf method to account for the boundary conditions at the termination of a thin cylindrical pipe. The purpose of this study is to develop a computational routine to predict the reflection coefficients of higher order acoustic modes impinging on the unflanged termination of a cylindrical duct. This effort was conducted wider Task Order 5 of the NASA Lewis LET Program, Active Noise Control of aircraft Engines: Feasibility Study, and will be used as part of the development of an integrated source noise, acoustic propagation, ANC actuator coupling, and control system algorithm simulation. The reflection coefficient prediction will be incorporated into an existing cylindrical duct modal analysis to account for the reflection of modes from the duct termination. This will provide a more accurate, rapid computation design tool for evaluating the effect of reflected waves on active noise control systems mounted in the duct, as well as providing a tool for the design of acoustic treatment in inlet ducts. As an active noise control system design tool, the method can be used preliminary to more accurate but more numerically intensive acoustic propagation models such as finite element methods. The resulting computer program has been shown to give reasonable results, some examples of which are presented. Reliable data to use for comparison is scarce, so complete checkout is difficult, and further checkout is needed over a wider range of system parameters. In future efforts the method will be adapted as a subroutine to the GEAE segmented cylindrical duct modal analysis program.
State-of-the-art review of computational fluid dynamics modeling for fluid-solids systems
NASA Astrophysics Data System (ADS)
Lyczkowski, R. W.; Bouillard, J. X.; Ding, J.; Chang, S. L.; Burge, S. W.
1994-05-01
As the result of 15 years of research (50 staff years of effort) Argonne National Laboratory (ANL), through its involvement in fluidized-bed combustion, magnetohydrodynamics, and a variety of environmental programs, has produced extensive computational fluid dynamics (CFD) software and models to predict the multiphase hydrodynamic and reactive behavior of fluid-solids motions and interactions in complex fluidized-bed reactors (FBR's) and slurry systems. This has resulted in the FLUFIX, IRF, and SLUFIX computer programs. These programs are based on fluid-solids hydrodynamic models and can predict information important to the designer of atmospheric or pressurized bubbling and circulating FBR, fluid catalytic cracking (FCC) and slurry units to guarantee optimum efficiency with minimum release of pollutants into the environment. This latter issue will become of paramount importance with the enactment of the Clean Air Act Amendment (CAAA) of 1995. Solids motion is also the key to understanding erosion processes. Erosion rates in FBR's and pneumatic and slurry components are computed by ANL's EROSION code to predict the potential metal wastage of FBR walls, intervals, feed distributors, and cyclones. Only the FLUFIX and IRF codes will be reviewed in the paper together with highlights of the validations because of length limitations. It is envisioned that one day, these codes with user-friendly pre- and post-processor software and tailored for massively parallel multiprocessor shared memory computational platforms will be used by industry and researchers to assist in reducing and/or eliminating the environmental and economic barriers which limit full consideration of coal, shale, and biomass as energy sources; to retain energy security; and to remediate waste and ecological problems.
Improved numerical methods for turbulent viscous flows aerothermal modeling program, phase 2
NASA Technical Reports Server (NTRS)
Karki, K. C.; Patankar, S. V.; Runchal, A. K.; Mongia, H. C.
1988-01-01
The details of a study to develop accurate and efficient numerical schemes to predict complex flows are described. In this program, several discretization schemes were evaluated using simple test cases. This assessment led to the selection of three schemes for an in-depth evaluation based on two-dimensional flows. The scheme with the superior overall performance was incorporated in a computer program for three-dimensional flows. To improve the computational efficiency, the selected discretization scheme was combined with a direct solution approach in which the fluid flow equations are solved simultaneously rather than sequentially.
NASA Technical Reports Server (NTRS)
Magnus, A. E.; Epton, M. A.
1981-01-01
Panel aerodynamics (PAN AIR) is a system of computer programs designed to analyze subsonic and supersonic inviscid flows about arbitrary configurations. A panel method is a program which solves a linear partial differential equation by approximating the configuration surface by a set of panels. An overview of the theory of potential flow in general and PAN AIR in particular is given along with detailed mathematical formulations. Fluid dynamics, the Navier-Stokes equation, and the theory of panel methods were also discussed.
Method to predict external store carriage characteristics at transonic speeds
NASA Technical Reports Server (NTRS)
Rosen, Bruce S.
1988-01-01
Development of a computational method for prediction of external store carriage characteristics at transonic speeds is described. The geometric flexibility required for treatment of pylon-mounted stores is achieved by computing finite difference solutions on a five-level embedded grid arrangement. A completely automated grid generation procedure facilitates applications. Store modeling capability consists of bodies of revolution with multiple fore and aft fins. A body-conforming grid improves the accuracy of the computed store body flow field. A nonlinear relaxation scheme developed specifically for modified transonic small disturbance flow equations enhances the method's numerical stability and accuracy. As a result, treatment of lower aspect ratio, more highly swept and tapered wings is possible. A limited supersonic freestream capability is also provided. Pressure, load distribution, and force/moment correlations show good agreement with experimental data for several test cases. A detailed computer program description for the Transonic Store Carriage Loads Prediction (TSCLP) Code is included.
NASA Technical Reports Server (NTRS)
Bennett, Robert M.; Batina, John T.
1989-01-01
The application and assessment of a computer program called CAP-TSD (Computational Aeroelasticity Program - Transonic Small Disturbance) for flutter predictions are described. Flutter calculations are presented for two thin swept-and-tapered wing planforms with well-defined modal properties. One planform is a series of 45-degree swept wings and the other planform is a clipped delta wing. Comparisons are made between the results of CAP-TSD using the linear equation and no airfoil thickness and the results obtained from a subsonic kernel function analysis. The calculations cover a Mach number range from low subsonic to low supersonic values, including the transonic range, and are compared with subsonic linear theory and experimental data. It is noted that since both wings have very thin airfoil sections, the effects of thickness are minimal.
Technically Speaking: Why Should You Use Virtual Grower?
USDA-ARS?s Scientific Manuscript database
Virtual Grower is a free, easy-to-use software program that every grower who heats their greenhouse should install on their computer. The program enables growers to simulate their own greenhouse and predict how changes or investments could impact the growing environment, heating costs, and crop res...
The use of computer graphics in the visual analysis of the proposed Sunshine Ski Area expansion
Mark Angelo
1979-01-01
This paper describes the use of computer graphics in designing part of the Sunshine Ski Area in Banff National Park. The program used was capable of generating perspective landscape drawings from a number of different viewpoints. This allowed managers to predict, and subsequently reduce, the adverse visual impacts of ski-run development. Computer graphics have proven,...
Development of a computer method for predicting lumber cutting yields.
Daniel E. Dunmire; George H. Englerth
1967-01-01
A system of locating defects in a board by intersecting coordinate points was developed and a computer program devised that used these points to locate all possible clear areas in the board. The computer determined the yields by placing any given size or sizes of cuttings in these clear areas, and furthermore stated the type, location, and number of saw cuts. The...
Computer programs for predicting supersonic and hypersonic interference flow fields and heating
NASA Technical Reports Server (NTRS)
Morris, D. J.; Keyes, J. W.
1973-01-01
This report describes computer codes which calculate two-dimensional shock interference patterns. These codes compute the six types of interference flows as defined by Edney (Aeronaut. Res. Inst. of Sweden FAA Rep. 115). Results include properties of the inviscid flow field and the inviscid-viscous interaction at the surface along with peak pressure and peak heating at the impingement point.
The microcomputer scientific software series 4: testing prediction accuracy.
H. Michael Rauscher
1986-01-01
A computer program, ATEST, is described in this combination user's guide / programmer's manual. ATEST provides users with an efficient and convenient tool to test the accuracy of predictors. As input ATEST requires observed-predicted data pairs. The output reports the two components of accuracy, bias and precision.
A review and update of the NASA aircraft noise prediction program propeller analysis system
NASA Technical Reports Server (NTRS)
Golub, Robert A.; Nguyen, L. Cathy
1989-01-01
The National Aeronautics and Space Administration (NASA) Aircraft Noise Prediction Program (ANOPP) Propeller Analysis System (PAS) is a set of computational modules for predicting the aerodynamics, performance, and noise of propellers. The ANOPP PAS has the capability to predict noise levels for propeller aircraft certification and produce parametric scaling laws for the adjustment of measured data to reference conditions. A technical overview of the prediction techniques incorporated into the system is presented. The prediction system has been applied to predict the noise signature of a variety of propeller configurations including the effects of propeller angle of attack. A summary of these validation studies is discussed with emphasis being placed on the wind tunnel and flight test programs sponsored by the Federal Aviation Administration (FAA) for the Piper Cherokee Lance aircraft. A number of modifications and improvements have been made to the system and both DEC VAX and IBM-PC versions of the system have been added to the original CDC NOS version.
NASA Astrophysics Data System (ADS)
McCreery, Glenn Ernest
An experimental and analytical investigation of dispersed and dispersed-annular (rivulet or thin film) flow phase separation in tees has been successfully completed. The research was directed at, but is not specific to, determining flow conditions, following a loss of coolant accident, in the large rectangular passageways leading to vacuum buildings in the containment envelope of some CANDU nuclear reactors. The primary objectives of the research were to: (1) obtain experimental data to help formulate and test mechanistic analytical models of phase separation, and (2) develop the analytical models in computer programs which predict phase separation from upstream flow and pressure conditions and downstream and side branch pressure boundary conditions. To meet these objectives an air-water experimental apparatus was constructed, and consists of large air blowers attached to a long rectangular duct leading to a tee in the horizontal plane. A variety of phenomena was investigated including, for comparison with computer predictions, air streamlines and eddy boundary geometry, drop size spectra, macroscopic mass balances, liquid rivulet pathlines, and trajectories of drops of known size and velocity. Four separate computer programs were developed to analyze phase separation. Three of the programs are used sequentially to calculate dispersed mist phase separation in a tee. The fourth is used to calculate rivulet or thin film pathlines. Macroscopic mass balances are calculated from a summation of mass balances for drops with representative sizes (and masses) spaced across the drop size spectrum. The programs are tested against experimental data, and accurately predict gas flow fields, drop trajectories, rivulet pathlines and macroscopic mass balances. In addition to development of the computer programs, analysis was performed to specify the scaling of dispersed mist and rivulet or thin film flow, to investigate pressure losses in tees, and the inter-relationship of loss coefficients, contraction coefficients, and eddy geometry. The important transient effects of liquid storage in eddies were also analyzed.
Banta, Edward R.; Poeter, Eileen P.; Doherty, John E.; Hill, Mary C.
2006-01-01
he Joint Universal Parameter IdenTification and Evaluation of Reliability Application Programming Interface (JUPITER API) improves the computer programming resources available to those developing applications (computer programs) for model analysis.The JUPITER API consists of eleven Fortran-90 modules that provide for encapsulation of data and operations on that data. Each module contains one or more entities: data, data types, subroutines, functions, and generic interfaces. The modules do not constitute computer programs themselves; instead, they are used to construct computer programs. Such computer programs are called applications of the API. The API provides common modeling operations for use by a variety of computer applications.The models being analyzed are referred to here as process models, and may, for example, represent the physics, chemistry, and(or) biology of a field or laboratory system. Process models commonly are constructed using published models such as MODFLOW (Harbaugh et al., 2000; Harbaugh, 2005), MT3DMS (Zheng and Wang, 1996), HSPF (Bicknell et al., 1997), PRMS (Leavesley and Stannard, 1995), and many others. The process model may be accessed by a JUPITER API application as an external program, or it may be implemented as a subroutine within a JUPITER API application . In either case, execution of the model takes place in a framework designed by the application programmer. This framework can be designed to take advantage of any parallel processing capabilities possessed by the process model, as well as the parallel-processing capabilities of the JUPITER API.Model analyses for which the JUPITER API could be useful include, for example: Compare model results to observed values to determine how well the model reproduces system processes and characteristics.Use sensitivity analysis to determine the information provided by observations to parameters and predictions of interest.Determine the additional data needed to improve selected model predictions.Use calibration methods to modify parameter values and other aspects of the model.Compare predictions to regulatory limits.Quantify the uncertainty of predictions based on the results of one or many simulations using inferential or Monte Carlo methods.Determine how to manage the system to achieve stated objectives.The capabilities provided by the JUPITER API include, for example, communication with process models, parallel computations, compressed storage of matrices, and flexible input capabilities. The input capabilities use input blocks suitable for lists or arrays of data. The input blocks needed for one application can be included within one data file or distributed among many files. Data exchange between different JUPITER API applications or between applications and other programs is supported by data-exchange files.The JUPITER API has already been used to construct a number of applications. Three simple example applications are presented in this report. More complicated applications include the universal inverse code UCODE_2005 (Poeter et al., 2005), the multi-model analysis MMA (Eileen P. Poeter, Mary C. Hill, E.R. Banta, S.W. Mehl, and Steen Christensen, written commun., 2006), and a code named OPR_PPR (Matthew J. Tonkin, Claire R. Tiedeman, Mary C. Hill, and D. Matthew Ely, written communication, 2006).This report describes a set of underlying organizational concepts and complete specifics about the JUPITER API. While understanding the organizational concept presented is useful to understanding the modules, other organizational concepts can be used in applications constructed using the JUPITER API.
NASA Technical Reports Server (NTRS)
Fogel, L. J.; Calabrese, P. G.; Walsh, M. J.; Owens, A. J.
1982-01-01
Ways in which autonomous behavior of spacecraft can be extended to treat situations wherein a closed loop control by a human may not be appropriate or even possible are explored. Predictive models that minimize mean least squared error and arbitrary cost functions are discussed. A methodology for extracting cyclic components for an arbitrary environment with respect to usual and arbitrary criteria is developed. An approach to prediction and control based on evolutionary programming is outlined. A computer program capable of predicting time series is presented. A design of a control system for a robotic dense with partially unknown physical properties is presented.
NASA Technical Reports Server (NTRS)
Dunn, M. H.; Tarkenton, G. M.
1992-01-01
This document describes the computational aspects of propeller noise prediction in the time domain and the use of high speed propeller noise prediction program ASSPIN (Advanced Subsonic and Supersonic Propeller Induced Noise). These formulations are valid in both the near and far fields. Two formulations are utilized by ASSPIN: (1) one is used for subsonic portions of the propeller blade; and (2) the second is used for transonic and supersonic regions on the blade. Switching between the two formulations is done automatically. ASSPIN incorporates advanced blade geometry and surface pressure modelling, adaptive observer time grid strategies, and contains enhanced numerical algorithms that result in reduced computational time. In addition, the ability to treat the nonaxial inflow case has been included.
Development of a prototype automatic controller for liquid cooling garment inlet temperature
NASA Technical Reports Server (NTRS)
Weaver, C. S.; Webbon, B. W.; Montgomery, L. D.
1982-01-01
The development of a computer control of a liquid cooled garment (LCG) inlet temperature is descirbed. An adaptive model of the LCG is used to predict the heat-removal rates for various inlet temperatures. An experimental system that contains a microcomputer was constructed. The LCG inlet and outlet temperatures and the heat exchanger outlet temperature form the inputs to the computer. The adaptive model prediction method of control is successful during tests where the inlet temperature is automatically chosen by the computer. It is concluded that the program can be implemented in a microprocessor of a size that is practical for a life support back-pack.
Computer technology forecast study for general aviation
NASA Technical Reports Server (NTRS)
Seacord, C. L.; Vaughn, D.
1976-01-01
A multi-year, multi-faceted program is underway to investigate and develop potential improvements in airframes, engines, and avionics for general aviation aircraft. The objective of this study was to assemble information that will allow the government to assess the trends in computer and computer/operator interface technology that may have application to general aviation in the 1980's and beyond. The current state of the art of computer hardware is assessed, technical developments in computer hardware are predicted, and nonaviation large volume users of computer hardware are identified.
Broadband Fan Noise Prediction System for Turbofan Engines. Volume 3; Validation and Test Cases
NASA Technical Reports Server (NTRS)
Morin, Bruce L.
2010-01-01
Pratt & Whitney has developed a Broadband Fan Noise Prediction System (BFaNS) for turbofan engines. This system computes the noise generated by turbulence impinging on the leading edges of the fan and fan exit guide vane, and noise generated by boundary-layer turbulence passing over the fan trailing edge. BFaNS has been validated on three fan rigs that were tested during the NASA Advanced Subsonic Technology Program (AST). The predicted noise spectra agreed well with measured data. The predicted effects of fan speed, vane count, and vane sweep also agreed well with measurements. The noise prediction system consists of two computer programs: Setup_BFaNS and BFaNS. Setup_BFaNS converts user-specified geometry and flow-field information into a BFaNS input file. From this input file, BFaNS computes the inlet and aft broadband sound power spectra generated by the fan and FEGV. The output file from BFaNS contains the inlet, aft and total sound power spectra from each noise source. This report is the third volume of a three-volume set documenting the Broadband Fan Noise Prediction System: Volume 1: Setup_BFaNS User s Manual and Developer s Guide; Volume 2: BFaNS User s Manual and Developer s Guide; and Volume 3: Validation and Test Cases. The present volume begins with an overview of the Broadband Fan Noise Prediction System, followed by validation studies that were done on three fan rigs. It concludes with recommended improvements and additional studies for BFaNS.
SeedVicious: Analysis of microRNA target and near-target sites.
Marco, Antonio
2018-01-01
Here I describe seedVicious, a versatile microRNA target site prediction software that can be easily fitted into annotation pipelines and run over custom datasets. SeedVicious finds microRNA canonical sites plus other, less efficient, target sites. Among other novel features, seedVicious can compute evolutionary gains/losses of target sites using maximum parsimony, and also detect near-target sites, which have one nucleotide different from a canonical site. Near-target sites are important to study population variation in microRNA regulation. Some analyses suggest that near-target sites may also be functional sites, although there is no conclusive evidence for that, and they may actually be target alleles segregating in a population. SeedVicious does not aim to outperform but to complement existing microRNA prediction tools. For instance, the precision of TargetScan is almost doubled (from 11% to ~20%) when we filter predictions by the distance between target sites using this program. Interestingly, two adjacent canonical target sites are more likely to be present in bona fide target transcripts than pairs of target sites at slightly longer distances. The software is written in Perl and runs on 64-bit Unix computers (Linux and MacOS X). Users with no computing experience can also run the program in a dedicated web-server by uploading custom data, or browse pre-computed predictions. SeedVicious and its associated web-server and database (SeedBank) are distributed under the GPL/GNU license.
Light aircraft crash safety program
NASA Technical Reports Server (NTRS)
Thomson, R. G.; Hayduk, R. J.
1974-01-01
NASA is embarked upon research and development tasks aimed at providing the general aviation industry with a reliable crashworthy airframe design technology. The goals of the NASA program are: reliable analytical techniques for predicting the nonlinear behavior of structures; significant design improvements of airframes; and simulated full-scale crash test data. The analytical tools will include both simplified procedures for estimating energy absorption characteristics and more complex computer programs for analysis of general airframe structures under crash loading conditions. The analytical techniques being developed both in-house and under contract are described, and a comparison of some analytical predictions with experimental results is shown.
Space radiator simulation manual for computer code
NASA Technical Reports Server (NTRS)
Black, W. Z.; Wulff, W.
1972-01-01
A computer program that simulates the performance of a space radiator is presented. The program basically consists of a rigorous analysis which analyzes a symmetrical fin panel and an approximate analysis that predicts system characteristics for cases of non-symmetrical operation. The rigorous analysis accounts for both transient and steady state performance including aerodynamic and radiant heating of the radiator system. The approximate analysis considers only steady state operation with no aerodynamic heating. A description of the radiator system and instructions to the user for program operation is included. The input required for the execution of all program options is described. Several examples of program output are contained in this section. Sample output includes the radiator performance during ascent, reentry and orbit.
The 1991 version of the plume impingement computer program. Volume 2: User's input guide
NASA Technical Reports Server (NTRS)
Bender, Robert L.; Somers, Richard E.; Prendergast, Maurice J.; Clayton, Joseph P.; Smith, Sheldon D.
1991-01-01
The Plume Impingement Program (PLIMP) is a computer code used to predict impact pressures, forces, moments, heating rates, and contamination on surfaces due to direct impingement flowfields. Typically, it has been used to analyze the effects of rocket exhaust plumes on nearby structures from ground level to the vacuum of space. The program normally uses flowfields generated by the MOC, RAMP2, SPF/2, or SFPGEN computer programs. It is capable of analyzing gaseous and gas/particle flows. A number of simple subshapes are available to model the surfaces of any structure. The original PLIMP program has been modified many times of the last 20 years. The theoretical bases for the referenced major changes, and additional undocumented changes and enhancements since 1988 are summarized in volume 1 of this report. This volume is the User's Input Guide and should be substituted for all previous guides when running the latest version of the program. This version can operate on VAX and UNIX machines with NCAR graphics ability.
A shock wave capability for the improved Two-Dimensional Kinetics (TDK) computer program
NASA Technical Reports Server (NTRS)
Nickerson, G. R.; Dang, L. D.
1984-01-01
The Two Dimensional Kinetics (TDK) computer program is a primary tool in applying the JANNAF liquid rocket engine performance prediction procedures. The purpose of this contract has been to improve the TDK computer program so that it can be applied to rocket engine designs of advanced type. In particular, future orbit transfer vehicles (OTV) will require rocket engines that operate at high expansion ratio, i.e., in excess of 200:1. Because only a limited length is available in the space shuttle bay, it is possible that OTV nozzles will be designed with both relatively short length and high expansion ratio. In this case, a shock wave may be present in the flow. The TDK computer program was modified to include the simulation of shock waves in the supersonic nozzle flow field. The shocks induced by the wall contour can produce strong perturbations of the flow, affecting downstream conditions which need to be considered for thrust chamber performance calculations.
NASA Technical Reports Server (NTRS)
Ramakrishnan, R.; Randall, D.; Hosier, R. N.
1976-01-01
The programing language used is FORTRAN IV. A description of all main and subprograms is provided so that any user possessing a FORTRAN compiler and random access capability can adapt the program to his facility. Rotor blade surface-pressure spectra can be used by the program to calculate: (1) blade station loading spectra, (2) chordwise and/or spanwise integrated blade-loading spectra, and (3) far-field rotational noise spectra. Any of five standard inline functions describing the chordwise distribution of the blade loading can be chosen in order to study parametrically the acoustic predictions. The program output consists of both printed and graphic descriptions of the blade-loading coefficient spectra and far-field acoustic spectrum. The results may also be written on binary file for future processing. Examples of the application of the program along with a description of the rotational noise prediction theory on which the program is based are also provided.
The U.S. EPA's ToxCast Chemical Screening Program and Predictive Modeling of Toxicity
The ToxCast program was developed by the U.S. EPA's National Center for Computational Toxicology to provide cost-effective high-throughput screening for the potential toxicity of thousands of chemicals. Phase I screened 309 compounds in over 500 assays to evaluate concentration-...
Condensation of wet vapors in turbines
NASA Technical Reports Server (NTRS)
Kothman, R. E.
1970-01-01
Computer program predicts condensation point in wet vapor turbines and analyzes subsequent nucleation and growth processes to determine both moisture content and drop size and number distribution as a function of position. Program includes effects of molecular association on condensation and flow processes and handles both subsonic and supersonic flows.
A root-mean-square approach for predicting fatigue crack growth under random loading
NASA Technical Reports Server (NTRS)
Hudson, C. M.
1981-01-01
A method for predicting fatigue crack growth under random loading which employs the concept of Barsom (1976) is presented. In accordance with this method, the loading history for each specimen is analyzed to determine the root-mean-square maximum and minimum stresses, and the predictions are made by assuming the tests have been conducted under constant-amplitude loading at the root-mean-square maximum and minimum levels. The procedure requires a simple computer program and a desk-top computer. For the eleven predictions made, the ratios of the predicted lives to the test lives ranged from 2.13 to 0.82, which is a good result, considering that the normal scatter in the fatigue-crack-growth rates may range from a factor of two to four under identical loading conditions.
Multiplexed Predictive Control of a Large Commercial Turbofan Engine
NASA Technical Reports Server (NTRS)
Richter, hanz; Singaraju, Anil; Litt, Jonathan S.
2008-01-01
Model predictive control is a strategy well-suited to handle the highly complex, nonlinear, uncertain, and constrained dynamics involved in aircraft engine control problems. However, it has thus far been infeasible to implement model predictive control in engine control applications, because of the combination of model complexity and the time allotted for the control update calculation. In this paper, a multiplexed implementation is proposed that dramatically reduces the computational burden of the quadratic programming optimization that must be solved online as part of the model-predictive-control algorithm. Actuator updates are calculated sequentially and cyclically in a multiplexed implementation, as opposed to the simultaneous optimization taking place in conventional model predictive control. Theoretical aspects are discussed based on a nominal model, and actual computational savings are demonstrated using a realistic commercial engine model.
How to use hand-held computers to evaluate wood drying.
Howard N. Rosen; Darrell S. Martin
1985-01-01
Techniques have been developed to evaluate end generate wood drying curves with hand-held computers (3-5K memory). Predictions of time to dry to a specific moisture content, drying rates, and other characteristics of wood drying curves can be made. The paper describes the development of programs and illustrates their use.
Numerical Prediction of Pitch Damping Stability Derivatives for Finned Projectiles
2013-11-01
in part by a grant of high-performance computing time from the U.S. DOD High Performance Computing Modernization Program (HPCMP) at the Army...to average 1 hour per response, including the time for reviewing instructions, searching existing data sources, gathering and maintaining the data...12 3.3.2 Time -Accurate Simulations
NASA Technical Reports Server (NTRS)
Muffoletto, A. J.
1982-01-01
An aerodynamic computer code, capable of predicting unsteady and C sub m values for an airfoil undergoing dynamic stall, is used to predict the amplitudes and frequencies of a wing undergoing torsional stall flutter. The code, developed at United Technologies Research Corporation (UTRC), is an empirical prediction method designed to yield unsteady values of normal force and moment, given the airfoil's static coefficient characteristics and the unsteady aerodynamic values, alpha, A and B. In this experiment, conducted in the PSU 4' x 5' subsonic wind tunnel, the wing's elastic axis, torsional spring constant and initial angle of attack are varied, and the oscillation amplitudes and frequencies of the wing, while undergoing torsional stall flutter, are recorded. These experimental values show only fair comparisons with the predicted responses. Predictions tend to be good at low velocities and rather poor at higher velocities.
Arora, Sanjeevani; Huwe, Peter J.; Sikder, Rahmat; Shah, Manali; Browne, Amanda J.; Lesh, Randy; Nicolas, Emmanuelle; Deshpande, Sanat; Hall, Michael J.; Dunbrack, Roland L.; Golemis, Erica A.
2017-01-01
ABSTRACT The cancer-predisposing Lynch Syndrome (LS) arises from germline mutations in DNA mismatch repair (MMR) genes, predominantly MLH1, MSH2, MSH6, and PMS2. A major challenge for clinical diagnosis of LS is the frequent identification of variants of uncertain significance (VUS) in these genes, as it is often difficult to determine variant pathogenicity, particularly for missense variants. Generic programs such as SIFT and PolyPhen-2, and MMR gene-specific programs such as PON-MMR and MAPP-MMR, are often used to predict deleterious or neutral effects of VUS in MMR genes. We evaluated the performance of multiple predictive programs in the context of functional biologic data for 15 VUS in MLH1, MSH2, and PMS2. Using cell line models, we characterized VUS predicted to range from neutral to pathogenic on mRNA and protein expression, basal cellular viability, viability following treatment with a panel of DNA-damaging agents, and functionality in DNA damage response (DDR) signaling, benchmarking to wild-type MMR proteins. Our results suggest that the MMR gene-specific classifiers do not always align with the experimental phenotypes related to DDR. Our study highlights the importance of complementary experimental and computational assessment to develop future predictors for the assessment of VUS. PMID:28494185
NASA Technical Reports Server (NTRS)
Smith, Tamara A.; Pavli, Albert J.; Kacynski, Kenneth J.
1987-01-01
The joint Army. Navy, NASA. Air Force (JANNAF) rocket engine peformnace prediction procedure is based on the use of various reference computer programs. One of the reference programs for nozzle analysis is the Two-Dimensional Kinetics (TDK) Program. The purpose of this report is to calibrate the JANNAF procedure incorporated into the December l984 version of the TDK program for the high-area-ratio rocket engine regime. The calibration was accomplished by modeling the performance of a 1030:1 rocket nozzle tested at NASA Lewis Research Center. A detailed description of the experimental test conditions and TDK input parameters is given. The results show that the computer code predicts delivered vacuum specific impulse to within 0.12 to 1.9 percent of the experimental data. Vacuum thrust coefficient predictions were within + or - 1.3 percent of experimental results. Predictions of wall static pressure were within approximately + or - 5 percent of the measured values. An experimental value for inviscid thrust was obtained for the nozzle extension between area ratios of 427.5 and 1030 by using an integration of the measured wall static pressures. Subtracting the measured thrust gain produced by the nozzle between area ratios of 427.5 and 1030 from the inviscid thrust gain yielded experimental drag decrements of 10.85 and 27.00 N (2.44 and 6.07 lb) for mixture ratios of 3.04 and 4.29, respectively. These values correspond to 0.45 and 1.11 percent of the total vacuum thrust. At a mixture ratio of 4.29, the TDK predicted drag decrement was 16.59 N (3.73 lb), or 0.71 percent of the predicted total vacuum thrust.
Computer codes for thermal analysis of a solid rocket motor nozzle
NASA Technical Reports Server (NTRS)
Chauhan, Rajinder Singh
1988-01-01
A number of computer codes are available for performing thermal analysis of solid rocket motor nozzles. Aerotherm Chemical Equilibrium (ACE) computer program can be used to perform one-dimensional gas expansion to determine the state of the gas at each location of a nozzle. The ACE outputs can be used as input to a computer program called Momentum/Energy Integral Technique (MEIT) for predicting boundary layer development development, shear, and heating on the surface of the nozzle. The output from MEIT can be used as input to another computer program called Aerotherm Charring Material Thermal Response and Ablation Program (CMA). This program is used to calculate oblation or decomposition response of the nozzle material. A code called Failure Analysis Nonlinear Thermal and Structural Integrated Code (FANTASTIC) is also likely to be used for performing thermal analysis of solid rocket motor nozzles after the program is duly verified. A part of the verification work on FANTASTIC was done by using one and two dimension heat transfer examples with known answers. An attempt was made to prepare input for performing thermal analysis of the CCT nozzle using the FANTASTIC computer code. The CCT nozzle problem will first be solved by using ACE, MEIT, and CMA. The same problem will then be solved using FANTASTIC. These results will then be compared for verification of FANTASTIC.
Obtaining Reliable Predictions of Terrestrial Energy Coupling From Real-Time Solar Wind Measurement
NASA Technical Reports Server (NTRS)
Weimer, Daniel R.
2001-01-01
The first draft of a manuscript titled "Variable time delays in the propagation of the interplanetary magnetic field" has been completed, for submission to the Journal of Geophysical Research. In the preparation of this manuscript all data and analysis programs had been updated to the highest temporal resolution possible, at 16 seconds or better. The program which computes the "measured" IMF propagation time delays from these data has also undergone another improvement. In another significant development, a technique has been developed in order to predict IMF phase plane orientations, and the resulting time delays, using only measurements from a single satellite at L1. The "minimum variance" method is used for this computation. Further work will be done on optimizing the choice of several parameters for the minimum variance calculation.
NASA Technical Reports Server (NTRS)
Wright, R. M.; Hwang, K. C.
1973-01-01
The sorbent behavior of solid amine resin IR-45 with regard to potential use in regenerative CO2-removal systems for manned spacecraft is considered. Measurements of equilibrium sorption capacity of IR-45 for water and for CO2 are reported, and the dynamic mass transfer behavior of IR-45 beds is studied under conditions representative of those expected in a manned spacecraft. A digital computer program was written for the transient performance prediction of CO2 removal systems comprised of solid amine beds. Also evaluated are systems employing inorganic molecular-sieve sorbents. Tests show that there is definitely an effect of water loading on the absorption rate.
Gaffney, Hannah; Mansell, Warren; Edwards, Rachel; Wright, Jason
2014-11-01
Computerized self-help that has an interactive, conversational format holds several advantages, such as flexibility across presenting problems and ease of use. We designed a new program called MYLO that utilizes the principles of METHOD of Levels (MOL) therapy--based upon Perceptual Control Theory (PCT). We tested the efficacy of MYLO, tested whether the psychological change mechanisms described by PCT mediated its efficacy, and evaluated effects of client expectancy. Forty-eight student participants were randomly assigned to MYLO or a comparison program ELIZA. Participants discussed a problem they were currently experiencing with their assigned program and completed measures of distress, resolution and expectancy preintervention, postintervention and at 2-week follow-up. MYLO and ELIZA were associated with reductions in distress, depression, anxiety and stress. MYLO was considered more helpful and led to greater problem resolution. The psychological change processes predicted higher ratings of MYLO's helpfulness and reductions in distress. Positive expectancies towards computer-based problem solving correlated with MYLO's perceived helpfulness and greater problem resolution, and this was partly mediated by the psychological change processes identified. The findings provide provisional support for the acceptability of the MYLO program in a non-clinical sample although its efficacy as an innovative computer-based aid to problem solving remains unclear. Nevertheless, the findings provide tentative early support for the mechanisms of psychological change identified within PCT and highlight the importance of client expectations on predicting engagement in computer-based self-help.
NASA Technical Reports Server (NTRS)
Magnus, Alfred E.; Epton, Michael A.
1981-01-01
An outline of the derivation of the differential equation governing linear subsonic and supersonic potential flow is given. The use of Green's Theorem to obtain an integral equation over the boundary surface is discussed. The engineering techniques incorporated in the PAN AIR (Panel Aerodynamics) program (a discretization method which solves the integral equation for arbitrary first order boundary conditions) are then discussed in detail. Items discussed include the construction of the compressibility transformations, splining techniques, imposition of the boundary conditions, influence coefficient computation (including the concept of the finite part of an integral), computation of pressure coefficients, and computation of forces and moments.
Incinerator ash dissolution model for the system: Plutonium, nitric acid and hydrofluoric acid
DOE Office of Scientific and Technical Information (OSTI.GOV)
Brown, E V
1988-06-01
This research accomplished two goals. The first was to develop a computer program to simulate a cascade dissolver system. This program would be used to predict the bulk rate of dissolution in incinerator ash. The other goal was to verify the model in a single-stage dissolver system using Dy/sub 2/O/sub 3/. PuO/sub 2/ (and all of the species in the incinerator ash) was assumed to exist as spherical particles. A model was used to calculate the bulk rate of plutonium oxide dissolution using fluoride as a catalyst. Once the bulk rate of PuO/sub 2/ dissolution and the dissolution rate ofmore » all soluble species were calculated, mass and energy balances were written. A computer program simulating the cascade dissolver system was then developed. Tests were conducted on a single-stage dissolver. A simulated incinerator ash mixture was made and added to the dissolver. CaF/sub 2/ was added to the mixture as a catalyst. A 9M HNO/sub 3/ solution was pumped into the dissolver system. Samples of the dissolver effluent were analyzed for dissolved and F concentrations. The computer program proved satisfactory in predicting the F concentrations in the dissolver effluent. The experimental sparge air flow rate was predicted to within 5.5%. The experimental percentage of solids dissolved (51.34%) compared favorably to the percentage of incinerator ash dissolved (47%) in previous work. No general conclusions on model verification could be reached. 56 refs., 11 figs., 24 tabs.« less
NASA Astrophysics Data System (ADS)
Terleev, V.; Ginevsky, R.; Lazarev, V.; Nikonorov, A.; Togo, I.; Topaj, A.; Moiseev, K.; Abakumov, E.; Melnichuk, A.; Dunaieva, I.
2017-10-01
A mathematical model of the hysteresis of the water-retention capacity of the soil is proposed. The parameters of the model are interpreted within the framework of physical concepts of the structure and capillary properties of soil pores. On the basis of the model, a computer program with an interface that allows for dialogue with the user is developed. The program has some of options: visualization of experimental data; identification of the model parameters with use of measured data by means of an optimizing algorithm; graphical presentation of the hysteresis loop with application of the assigned parameters. Using the program, computational experiments were carried out, which consisted in verifying the identifiability of the model parameters from data on the main branches, and also in testing the ability to predict the scanning branches of the hysteresis loop. For the experiments, literature data on two sandy soils were used. The absence of an “artificial pump effect” is proved. A sufficiently high accuracy of the prediction of the scanning branches of the hysteresis loop has been achieved in comparison with the three models of the precursors. The practical importance of the proposed model and computer program, which is developed on its basis, is to ensure the calculation of precision irrigation rates. The application of such rates in irrigation farming will help to prevent excess moisture from flowing beyond the root layer of the soil and, thus, minimize the unproductive loss of irrigation water and agrochemicals, as well as reduce the risk of groundwater contamination and natural water eutrophication.
NASA Technical Reports Server (NTRS)
Hall, E. J.; Topp, D. A.; Delaney, R. A.
1996-01-01
The overall objective of this study was to develop a 3-D numerical analysis for compressor casing treatment flowfields. The current version of the computer code resulting from this study is referred to as ADPAC (Advanced Ducted Propfan Analysis Codes-Version 7). This report is intended to serve as a computer program user's manual for the ADPAC code developed under Tasks 6 and 7 of the NASA Contract. The ADPAC program is based on a flexible multiple- block grid discretization scheme permitting coupled 2-D/3-D mesh block solutions with application to a wide variety of geometries. Aerodynamic calculations are based on a four-stage Runge-Kutta time-marching finite volume solution technique with added numerical dissipation. Steady flow predictions are accelerated by a multigrid procedure. An iterative implicit algorithm is available for rapid time-dependent flow calculations, and an advanced two equation turbulence model is incorporated to predict complex turbulent flows. The consolidated code generated during this study is capable of executing in either a serial or parallel computing mode from a single source code. Numerous examples are given in the form of test cases to demonstrate the utility of this approach for predicting the aerodynamics of modem turbomachinery configurations.
NASA Astrophysics Data System (ADS)
1991-03-01
This paper documents a very low frequency/low frequency (VLF/LF) Data Analysis task by the Naval Ocean Systems Center to improve the modeling of the nighttime ionosphere when making propagation predictions with the Long Wave Propagation Capability (LWPC) computer program. The task utilizes an extensive database of VLF measured data recorded during the 1985 to 1986 trips of the merchant ship GTS Callaghan in the North Atlantic area. By constraining the Callaghan data to those periods when both the ship and the distant transmitters were in time zones consistent with all-nighttime propagation, and by eliminating data from trips outside the principal area of interest, an aggregated set of recorded data was assembled for each frequency of concern. Four frequencies were examined: 16.0, 19.0, 21.4 and 24.0 kHz. Recorded data sets were graphed as signal vs. distance plots, computing distance from the transmitter for each ship's location. The LWPC program was then utilized to compute signal vs. distance along a typical path in the same ocean area, and the predicted and recorded data were compared. By changing the LWPC parameters different propagation predictions were compared with the recorded data until a best fit was obtained.
R.D. Ottmar; M.F. Burns; J.N. Hall; A.D. Hanson
1993-01-01
CONSUME is a user-friendly computer program designed for resource managers with some working knowledge of IBM-PC applications. The software predicts the amount of fuel consumption on logged units based on weather data, the amount and fuel moisture of fuels, and a number of other factors. Using these predictions, the resource manager can accurately determine when and...
NASA Technical Reports Server (NTRS)
Howell, W. E.
1974-01-01
The structural performance of a boron-epoxy reinforced titanium drag strut, which contains a bonded scarf joint and was designed to the criteria of the Boeing 747 transport, was evaluated. An experimental and analytical investigation was conducted. The strut was exposed to two lifetimes of spectrum loading and was statically loaded to the tensile and compressive design ultimate loads. Throughout the test program no evidence of any damage in the drag strut was detected by strain gage measurements, ultrasonic inspection, or visual observation. An analytical study of the bonded joint was made using the NASA structural analysis computer program NASTRAN. A comparison of the strains predicted by the NASTRAN computer program with the experimentally determined values shows excellent agreement. The NASTRAN computer program is a viable tool for studying, in detail, the stresses and strains induced in a bonded joint.
Vacuum ultraviolet line radiation measurements of a shock-heated nitrogen plasma
NASA Technical Reports Server (NTRS)
Mcclenahan, J. O.
1972-01-01
Line radiation, in the wavelength region from 1040 to 2500 A from nitrogen plasmas, was measured at conditions typical of those produced in the shock layer in front of vehicles entering the earth's atmosphere at superorbital velocities. The radiation was also predicted with a typical radiation transport computer program to determine whether such calculations adequately model plasmas for the conditions tested. The results of the comparison show that the radiant intensities of the lines between 1040 and 1700 A are actually lower than are predicted by such computer models.
NASA Technical Reports Server (NTRS)
Perkey, D. J.; Kreitzberg, C. W.
1984-01-01
The dynamic prediction model along with its macro-processor capability and data flow system from the Drexel Limited-Area and Mesoscale Prediction System (LAMPS) were converted and recorded for the Perkin-Elmer 3220. The previous version of this model was written for Control Data Corporation 7600 and CRAY-1a computer environment which existed until recently at the National Center for Atmospheric Research. The purpose of this conversion was to prepare LAMPS for porting to computer environments other than that encountered at NCAR. The emphasis was shifted from programming tasks to model simulation and evaluation tests.
The prediction of three-dimensional liquid-propellant rocket nozzle admittances
NASA Technical Reports Server (NTRS)
Bell, W. A.; Zinn, B. T.
1973-01-01
Crocco's three-dimensional nozzle admittance theory is extended to be applicable when the amplitudes of the combustor and nozzle oscillations increase or decrease with time. An analytical procedure and a computer program for determining nozzle admittance values from the extended theory are presented and used to compute the admittances of a family of liquid-propellant rocket nozzles. The calculated results indicate that the nozzle geometry entrance Mach number and temporal decay coefficient significantly affect the nozzle admittance values. The theoretical predictions are shown to be in good agreement with available experimental data.
Computational toxicology using the OpenTox application programming interface and Bioclipse
2011-01-01
Background Toxicity is a complex phenomenon involving the potential adverse effect on a range of biological functions. Predicting toxicity involves using a combination of experimental data (endpoints) and computational methods to generate a set of predictive models. Such models rely strongly on being able to integrate information from many sources. The required integration of biological and chemical information sources requires, however, a common language to express our knowledge ontologically, and interoperating services to build reliable predictive toxicology applications. Findings This article describes progress in extending the integrative bio- and cheminformatics platform Bioclipse to interoperate with OpenTox, a semantic web framework which supports open data exchange and toxicology model building. The Bioclipse workbench environment enables functionality from OpenTox web services and easy access to OpenTox resources for evaluating toxicity properties of query molecules. Relevant cases and interfaces based on ten neurotoxins are described to demonstrate the capabilities provided to the user. The integration takes advantage of semantic web technologies, thereby providing an open and simplifying communication standard. Additionally, the use of ontologies ensures proper interoperation and reliable integration of toxicity information from both experimental and computational sources. Conclusions A novel computational toxicity assessment platform was generated from integration of two open science platforms related to toxicology: Bioclipse, that combines a rich scriptable and graphical workbench environment for integration of diverse sets of information sources, and OpenTox, a platform for interoperable toxicology data and computational services. The combination provides improved reliability and operability for handling large data sets by the use of the Open Standards from the OpenTox Application Programming Interface. This enables simultaneous access to a variety of distributed predictive toxicology databases, and algorithm and model resources, taking advantage of the Bioclipse workbench handling the technical layers. PMID:22075173
Measuring Financial Gains from Genetically Superior Trees
George Dutrow; Clark Row
1976-01-01
Planting genetically superior loblolly pines will probably yield high profits.Forest economists have made computer simulations that predict financial gains expected from a tree improvement program under actual field conditions.
Kingsley, Laura J.; Lill, Markus A.
2014-01-01
Computational prediction of ligand entry and egress paths in proteins has become an emerging topic in computational biology and has proven useful in fields such as protein engineering and drug design. Geometric tunnel prediction programs, such as Caver3.0 and MolAxis, are computationally efficient methods to identify potential ligand entry and egress routes in proteins. Although many geometric tunnel programs are designed to accommodate a single input structure, the increasingly recognized importance of protein flexibility in tunnel formation and behavior has led to the more widespread use of protein ensembles in tunnel prediction. However, there has not yet been an attempt to directly investigate the influence of ensemble size and composition on geometric tunnel prediction. In this study, we compared tunnels found in a single crystal structure to ensembles of various sizes generated using different methods on both the apo and holo forms of cytochrome P450 enzymes CYP119, CYP2C9, and CYP3A4. Several protein structure clustering methods were tested in an attempt to generate smaller ensembles that were capable of reproducing the data from larger ensembles. Ultimately, we found that by including members from both the apo and holo data sets, we could produce ensembles containing less than 15 members that were comparable to apo or holo ensembles containing over 100 members. Furthermore, we found that, in the absence of either apo or holo crystal structure data, pseudo-apo or –holo ensembles (e.g. adding ligand to apo protein throughout MD simulations) could be used to resemble the structural ensembles of the corresponding apo and holo ensembles, respectively. Our findings not only further highlight the importance of including protein flexibility in geometric tunnel prediction, but also suggest that smaller ensembles can be as capable as larger ensembles at capturing many of the protein motions important for tunnel prediction at a lower computational cost. PMID:24956479
Performance of a parallel code for the Euler equations on hypercube computers
NASA Technical Reports Server (NTRS)
Barszcz, Eric; Chan, Tony F.; Jesperson, Dennis C.; Tuminaro, Raymond S.
1990-01-01
The performance of hypercubes were evaluated on a computational fluid dynamics problem and the parallel environment issues were considered that must be addressed, such as algorithm changes, implementation choices, programming effort, and programming environment. The evaluation focuses on a widely used fluid dynamics code, FLO52, which solves the two dimensional steady Euler equations describing flow around the airfoil. The code development experience is described, including interacting with the operating system, utilizing the message-passing communication system, and code modifications necessary to increase parallel efficiency. Results from two hypercube parallel computers (a 16-node iPSC/2, and a 512-node NCUBE/ten) are discussed and compared. In addition, a mathematical model of the execution time was developed as a function of several machine and algorithm parameters. This model accurately predicts the actual run times obtained and is used to explore the performance of the code in interesting but yet physically realizable regions of the parameter space. Based on this model, predictions about future hypercubes are made.
Kostal, Jakub; Voutchkova-Kostal, Adelina
2016-01-19
Using computer models to accurately predict toxicity outcomes is considered to be a major challenge. However, state-of-the-art computational chemistry techniques can now be incorporated in predictive models, supported by advances in mechanistic toxicology and the exponential growth of computing resources witnessed over the past decade. The CADRE (Computer-Aided Discovery and REdesign) platform relies on quantum-mechanical modeling of molecular interactions that represent key biochemical triggers in toxicity pathways. Here, we present an external validation exercise for CADRE-SS, a variant developed to predict the skin sensitization potential of commercial chemicals. CADRE-SS is a hybrid model that evaluates skin permeability using Monte Carlo simulations, assigns reactive centers in a molecule and possible biotransformations via expert rules, and determines reactivity with skin proteins via quantum-mechanical modeling. The results were promising with an overall very good concordance of 93% between experimental and predicted values. Comparison to performance metrics yielded by other tools available for this endpoint suggests that CADRE-SS offers distinct advantages for first-round screenings of chemicals and could be used as an in silico alternative to animal tests where permissible by legislative programs.
The use of wireless laptop computers for computer-assisted learning in pharmacokinetics.
Munar, Myrna Y; Singh, Harleen; Belle, Donna; Brackett, Carolyn C; Earle, Sandra B
2006-02-15
To implement computer-assisted learning workshops into pharmacokinetics courses in a doctor of pharmacy (PharmD) program. Workshops were designed for students to utilize computer software programs on laptop computers to build pharmacokinetic models to predict drug concentrations resulting from various dosage regimens. In addition, students were able to visualize through graphing programs how altering different parameters changed drug concentration-time curves. Surveys were conducted to measure students' attitudes toward computer technology before and after implementation. Finally, traditional examinations were used to evaluate student learning. Doctor of pharmacy students responded favorably to the use of wireless laptop computers in problem-based pharmacokinetic workshops. Eighty-eight percent (n = 61/69) and 82% (n = 55/67) of PharmD students completed surveys before and after computer implementation, respectively. Prior to implementation, 95% of students agreed that computers would enhance learning in pharmacokinetics. After implementation, 98% of students strongly agreed (p < 0.05) that computers enhanced learning. Examination results were significantly higher after computer implementation (89% with computers vs. 84% without computers; p = 0.01). Implementation of wireless laptop computers in a pharmacokinetic course enabled students to construct their own pharmacokinetic models that could respond to changing parameters. Students had greater comprehension and were better able to interpret results and provide appropriate recommendations. Computer-assisted pharmacokinetic techniques can be powerful tools when making decisions about drug therapy.
The Use of Wireless Laptop Computers for Computer-Assisted Learning in Pharmacokinetics
Munar, Myrna Y.; Singh, Harleen; Belle, Donna; Brackett, Carolyn C.; Earle, Sandra B.
2006-01-01
Objective To implement computer-assisted learning workshops into pharmacokinetics courses in a doctor of pharmacy (PharmD) program. Design Workshops were designed for students to utilize computer software programs on laptop computers to build pharmacokinetic models to predict drug concentrations resulting from various dosage regimens. In addition, students were able to visualize through graphing programs how altering different parameters changed drug concentration-time curves. Surveys were conducted to measure students’ attitudes toward computer technology before and after implementation. Finally, traditional examinations were used to evaluate student learning. Assessment Doctor of pharmacy students responded favorably to the use of wireless laptop computers in problem-based pharmacokinetic workshops. Eighty-eight percent (n = 61/69) and 82% (n = 55/67) of PharmD students completed surveys before and after computer implementation, respectively. Prior to implementation, 95% of students agreed that computers would enhance learning in pharmacokinetics. After implementation, 98% of students strongly agreed (p < 0.05) that computers enhanced learning. Examination results were significantly higher after computer implementation (89% with computers vs. 84% without computers; p = 0.01). Conclusion Implementation of wireless laptop computers in a pharmacokinetic course enabled students to construct their own pharmacokinetic models that could respond to changing parameters. Students had greater comprehension and were better able to interpret results and provide appropriate recommendations. Computer-assisted pharmacokinetic techniques can be powerful tools when making decisions about drug therapy. PMID:17136147
NASA Technical Reports Server (NTRS)
Silva, Walter A.
1993-01-01
A methodology for modeling nonlinear unsteady aerodynamic responses, for subsequent use in aeroservoelastic analysis and design, using the Volterra-Wiener theory of nonlinear systems is presented. The methodology is extended to predict nonlinear unsteady aerodynamic responses of arbitrary frequency. The Volterra-Wiener theory uses multidimensional convolution integrals to predict the response of nonlinear systems to arbitrary inputs. The CAP-TSD (Computational Aeroelasticity Program - Transonic Small Disturbance) code is used to generate linear and nonlinear unit impulse responses that correspond to each of the integrals for a rectangular wing with a NACA 0012 section with pitch and plunge degrees of freedom. The computed kernels then are used to predict linear and nonlinear unsteady aerodynamic responses via convolution and compared to responses obtained using the CAP-TSD code directly. The results indicate that the approach can be used to predict linear unsteady aerodynamic responses exactly for any input amplitude or frequency at a significant cost savings. Convolution of the nonlinear terms results in nonlinear unsteady aerodynamic responses that compare reasonably well with those computed using the CAP-TSD code directly but at significant computational cost savings.
Predicting neutron damage using TEM with in situ ion irradiation and computer modeling
NASA Astrophysics Data System (ADS)
Kirk, Marquis A.; Li, Meimei; Xu, Donghua; Wirth, Brian D.
2018-01-01
We have constructed a computer model of irradiation defect production closely coordinated with TEM and in situ ion irradiation of Molybdenum at 80 °C over a range of dose, dose rate and foil thickness. We have reexamined our previous ion irradiation data to assign appropriate error and uncertainty based on more recent work. The spatially dependent cascade cluster dynamics model is updated with recent Molecular Dynamics results for cascades in Mo. After a careful assignment of both ion and neutron irradiation dose values in dpa, TEM data are compared for both ion and neutron irradiated Mo from the same source material. Using the computer model of defect formation and evolution based on the in situ ion irradiation of thin foils, the defect microstructure, consisting of densities and sizes of dislocation loops, is predicted for neutron irradiation of bulk material at 80 °C and compared with experiment. Reasonable agreement between model prediction and experimental data demonstrates a promising direction in understanding and predicting neutron damage using a closely coordinated program of in situ ion irradiation experiment and computer simulation.
NASA Technical Reports Server (NTRS)
Bowers, A. H.; Sandlin, D. R.
1984-01-01
Computations of drag polars for a low-speed Wortmann sailplane airfoil are compared to both wind tunnel and flight results. Excellent correlation is shown to exist between computations and flight results except when separated flow regimes were encountered. Wind tunnel transition locations are shown to agree with computed predictions. Smoothness of the input coordinates to the PROFILE airfoil analysis computer program was found to be essential to obtain accurate comparisons of drag polars or transition location to either the flight or wind tunnel results.
NECAP: NASA's Energy-Cost Analysis Program. Part 1: User's manual
NASA Technical Reports Server (NTRS)
Henninger, R. H. (Editor)
1975-01-01
The NECAP is a sophisticated building design and energy analysis tool which has embodied within it all of the latest ASHRAE state-of-the-art techniques for performing thermal load calculation and energy usage predictions. It is a set of six individual computer programs which include: response factor program, data verification program, thermal load analysis program, variable temperature program, system and equipment simulation program, and owning and operating cost program. Each segment of NECAP is described, and instructions are set forth for preparing the required input data and for interpreting the resulting reports.
John K. Francis
1986-01-01
Intensive harvest of southern hardwoods can yield biomass in a greatly varied mix. This causes variation in the withdrawal rates of nutrients. A need exists for a computer program to perform biomass and nutrient content calculations on diverse stands. such a program BANR (Biomass And Nutrient Removal) - is described in this paper. It was written for the Hewlett-Packard...
NASA Technical Reports Server (NTRS)
Galvas, M. R.
1972-01-01
A computer program for predicting design point specific speed - efficiency characteristics of centrifugal compressors is presented with instructions for its use. The method permits rapid selection of compressor geometry that yields maximum total efficiency for a particular application. A numerical example is included to demonstrate the selection procedure.
Middle School English Language Learner Electronic Media Usage and Its Relationship to Reading
ERIC Educational Resources Information Center
Ramirez, Bari N.
2012-01-01
A quantitative, correlational prediction study was performed to determine the relationship between English language learner (ELL) use of electronic media and reading proficiency in a large urban middle school in Texas. The predictor variables were viewing television programs in English, viewing television programs in Spanish, using a computer for…
Synthetic mixed-signal computation in living cells
Rubens, Jacob R.; Selvaggio, Gianluca; Lu, Timothy K.
2016-01-01
Living cells implement complex computations on the continuous environmental signals that they encounter. These computations involve both analogue- and digital-like processing of signals to give rise to complex developmental programs, context-dependent behaviours and homeostatic activities. In contrast to natural biological systems, synthetic biological systems have largely focused on either digital or analogue computation separately. Here we integrate analogue and digital computation to implement complex hybrid synthetic genetic programs in living cells. We present a framework for building comparator gene circuits to digitize analogue inputs based on different thresholds. We then demonstrate that comparators can be predictably composed together to build band-pass filters, ternary logic systems and multi-level analogue-to-digital converters. In addition, we interface these analogue-to-digital circuits with other digital gene circuits to enable concentration-dependent logic. We expect that this hybrid computational paradigm will enable new industrial, diagnostic and therapeutic applications with engineered cells. PMID:27255669
New technology in turbine aerodynamics
NASA Technical Reports Server (NTRS)
Glassman, A. J.; Moffitt, T. P.
1972-01-01
A cursory review is presented of some of the recent work that has been done in turbine aerodynamic research at NASA-Lewis Research Center. Topics discussed include the aerodynamic effect of turbine coolant, high work-factor (ratio of stage work to square of blade speed) turbines, and computer methods for turbine design and performance prediction. An extensive bibliography is included. Experimental cooled-turbine aerodynamics programs using two-dimensional cascades, full annular cascades, and cold rotating turbine stage tests are discussed with some typical results presented. Analytically predicted results for cooled blade performance are compared to experimental results. The problems and some of the current programs associated with the use of very high work factors for fan-drive turbines of high-bypass-ratio engines are discussed. Turbines currently being investigated make use of advanced blading concepts designed to maintain high efficiency under conditions of high aerodynamic loading. Computer programs have been developed for turbine design-point performance, off-design performance, supersonic blade profile design, and the calculation of channel velocities for subsonic and transonic flow fields. The use of these programs for the design and analysis of axial and radial turbines is discussed.
ERIC Educational Resources Information Center
Lonigan, Christopher J.; Driscoll, Kimberly; Phillips, Beth M.; Cantor, Brenlee G.; Anthony, Jason L.; Goldstein, Howard
2003-01-01
A study evaluated the use of computer-assisted instruction (CAI) to provide training in phonological sensitivity skills to 45 preschool children at-risk for reading problems. Children exposed to CAI made significantly greater gains on rhyming and elision skills compared to controls. Expressive vocabulary scores were predictive of pre- to posttest…
NASA Technical Reports Server (NTRS)
Davis, J. W.; Cramer, B. A.
1976-01-01
A method of analysis was developed for predicting permanent cyclic creep deflections in stiffened panel structures. This method uses creep equations based on cyclic tensile creep tests and a computer program to predict panel deflections as a function of mission cycle. Four materials were investigated - a titanium alloy (Ti-6Al-4V), a cobalt alloy (L605), and two nickel alloys (Rene'41 and TDNiCr). Steady-state and cyclic creep response data were obtained by testing tensile specimens fabricated from thin gage sheet (0.025 and 0.63 cm nominal). Steady-state and cyclic creep equations were developed which describe creep as a function of time, temperature and load. Tests were also performed on subsize (6.35 x 30.5 cm) rib and corrugation stiffened panels. These tests were used to correlate creep responses between elemental specimens and panels. The panel response was analyzed by use of a specially written computer program.
A Worst-Case Approach for On-Line Flutter Prediction
NASA Technical Reports Server (NTRS)
Lind, Rick C.; Brenner, Martin J.
1998-01-01
Worst-case flutter margins may be computed for a linear model with respect to a set of uncertainty operators using the structured singular value. This paper considers an on-line implementation to compute these robust margins in a flight test program. Uncertainty descriptions are updated at test points to account for unmodeled time-varying dynamics of the airplane by ensuring the robust model is not invalidated by measured flight data. Robust margins computed with respect to this uncertainty remain conservative to the changing dynamics throughout the flight. A simulation clearly demonstrates this method can improve the efficiency of flight testing by accurately predicting the flutter margin to improve safety while reducing the necessary flight time.
Bettina Ohse; Falk Huettmann; Stefanie M. Ickert-Bond; Glenn P. Juday
2009-01-01
Most wilderness areas still lack accurate distribution information on tree species. We met this need with a predictive GIS modeling approach, using freely available digital data and computer programs to efficiently obtain high-quality species distribution maps. Here we present a digital map with the predicted distribution of white spruce (Picea glauca...
DOE Office of Scientific and Technical Information (OSTI.GOV)
Chen, T.F.; Mok, G.C.; Carlson, R.W.
1996-12-01
CASKS is a microcomputer based computer system developed by LLNL to assist the Nuclear Regulatory Commission in performing confirmatory analyses for licensing review of radioactive-material storage cask designs. The analysis programs of the CASKS computer system consist of four modules--the impact analysis module, the thermal analysis module, the thermally-induced stress analysis module, and the pressure-induced stress analysis module. CASKS uses a series of menus to coordinate input programs, cask analysis programs, output programs, data archive programs and databases, so the user is able to run the system in an interactive environment. This paper outlines the theoretical background on the impactmore » analysis module and the yielding surface formulation. The close agreement between the CASKS analytical predictions and the results obtained form the two storage asks drop tests performed by SNL and by BNFL at Winfrith serves as the validation of the CASKS impact analysis module.« less
DOE Office of Scientific and Technical Information (OSTI.GOV)
Chen, T.F.; Mok, G.C.; Carlson, R.W.
1995-08-01
CASKS is a microcomputer based computer system developed by LLNL to assist the Nuclear Regulatory Commission in performing confirmatory analyses for licensing review of radioactive-material storage cask designs. The analysis programs of the CASKS computer system consist of four modules: the impact analysis module, the thermal analysis module, the thermally-induced stress analysis module, and the pressure-induced stress analysis module. CASKS uses a series of menus to coordinate input programs, cask analysis programs, output programs, data archive programs and databases, so the user is able to run the system in an interactive environment. This paper outlines the theoretical background on themore » impact analysis module and the yielding surface formulation. The close agreement between the CASKS analytical predictions and the results obtained form the two storage casks drop tests performed by SNL and by BNFL at Winfrith serves as the validation of the CASKS impact analysis module.« less
Factors leading to different viability predictions for a grizzly bear data set
Mills, L.S.; Hayes, S.G.; Wisdom, M.J.; Citta, J.; Mattson, D.J.; Murphy, K.
1996-01-01
Population viability analysis programs are being used increasingly in research and management applications, but there has not been a systematic study of the congruence of different program predictions based on a single data set. We performed such an analysis using four population viability analysis computer programs: GAPPS, INMAT, RAMAS/AGE, and VORTEX. The standardized demographic rates used in all programs were generalized from hypothetical increasing and decreasing grizzly bear (Ursus arctos horribilis) populations. Idiosyncracies of input format for each program led to minor differences in intrinsic growth rates that translated into striking differences in estimates of extinction rates and expected population size. In contrast, the addition of demographic stochasticity, environmental stochasticity, and inbreeding costs caused only a small divergence in viability predictions. But, the addition of density dependence caused large deviations between the programs despite our best attempts to use the same density-dependent functions. Population viability programs differ in how density dependence is incorporated, and the necessary functions are difficult to parameterize accurately. Thus, we recommend that unless data clearly suggest a particular density-dependent model, predictions based on population viability analysis should include at least one scenario without density dependence. Further, we describe output metrics that may differ between programs; development of future software could benefit from standardized input and output formats across different programs.
Stress analyses of B-52 pylon hooks
NASA Technical Reports Server (NTRS)
Ko, W. L.; Schuster, L. S.
1985-01-01
The NASTRAN finite element computer program was used in the two dimensional stress analysis of B-52 carrier aircraft pylon hooks: (1) old rear hook (which failed), (2) new rear hook (improved geometry), (3) new DAST rear hook (derated geometry), and (4) front hook. NASTRAN model meshes were generated by the aid of PATRAN-G computer program. Brittle limit loads for all the four hooks were established. The critical stress level calculated from NASTRAN agrees reasonably well with the values predicted from the fracture mechanics for the failed old rear hook.
NASA Technical Reports Server (NTRS)
Austin, F.; Markowitz, J.; Goldenberg, S.; Zetkov, G. A.
1973-01-01
The formulation of a mathematical model for predicting the dynamic behavior of rotating flexible space station configurations was conducted. The overall objectives of the study were: (1) to develop the theoretical techniques for determining the behavior of a realistically modeled rotating space station, (2) to provide a versatile computer program for the numerical analysis, and (3) to present practical concepts for experimental verification of the analytical results. The mathematical model and its associated computer program are described.
Using artificial intelligence to control fluid flow computations
NASA Technical Reports Server (NTRS)
Gelsey, Andrew
1992-01-01
Computational simulation is an essential tool for the prediction of fluid flow. Many powerful simulation programs exist today. However, using these programs to reliably analyze fluid flow and other physical situations requires considerable human effort and expertise to set up a simulation, determine whether the output makes sense, and repeatedly run the simulation with different inputs until a satisfactory result is achieved. Automating this process is not only of considerable practical importance but will also significantly advance basic artificial intelligence (AI) research in reasoning about the physical world.
Control of the TSU 2-m automatic telescope
NASA Astrophysics Data System (ADS)
Eaton, Joel A.; Williamson, Michael H.
2004-09-01
Tennessee State University is operating a 2-m automatic telescope for high-dispersion spectroscopy. The alt-azimuth telescope is fiber-coupled to a conventional echelle spectrograph with two resolutions (R=30,000 and 70,000). We control this instrument with four computers running linux and communicating over ethernet through the UDP protocol. A computer physically located on the telescope handles the acquisition and tracking of stars. We avoid the need for real-time programming in this application by periodically latching the positions of the axes in a commercial motion controller and the time in a GPS receiver. A second (spectrograph) computer sets up the spectrograph and runs its CCD, a third (roof) computer controls the roll-off roof and front flap of the telescope enclosure, and the fourth (executive) computer makes decisions about which stars to observe and when to close the observatory for bad weather. The only human intervention in the telescope's operation involves changing the observing program, copying data back to TSU, and running quality-control checks on the data. It has been running reliably in this completely automatic, unattended mode for more than a year with all day-to-day adminsitration carried out over the Internet. To support automatic operation, we have written a number of useful tools to predict and analyze what the telescope does. These include a simulator that predicts roughly how the telescope will operate on a given night, a quality-control program to parse logfiles from the telescope and identify problems, and a rescheduling program that calculates new priorities to keep the frequency of observation for the various stars roughly as desired. We have also set up a database to keep track of the tens of thousands of spectra we expect to get each year.
Comparison of LEWICE and GlennICE in the SLD Regime
NASA Technical Reports Server (NTRS)
Wright, William B.; Potapczuk, Mark G.; Levinson, Laurie H.
2008-01-01
A research project is underway at the NASA Glenn Research Center (GRC) to produce computer software that can accurately predict ice growth under any meteorological conditions for any aircraft surface. This report will present results from two different computer programs. The first program, LEWICE version 3.2.2, has been reported on previously. The second program is GlennICE version 0.1. An extensive comparison of the results in a quantifiable manner against the database of ice shapes that have been generated in the GRC Icing Research Tunnel (IRT) has also been performed, including additional data taken to extend the database in the Super-cooled Large Drop (SLD) regime. This paper will show the differences in ice shape between LEWICE 3.2.2, GlennICE, and experimental data. This report will also provide a description of both programs. Comparisons are then made to recent additions to the SLD database and selected previous cases. Quantitative comparisons are shown for horn height, horn angle, icing limit, area, and leading edge thickness. The results show that the predicted results for both programs are within the accuracy limits of the experimental data for the majority of cases.
EGASP: the human ENCODE Genome Annotation Assessment Project
Guigó, Roderic; Flicek, Paul; Abril, Josep F; Reymond, Alexandre; Lagarde, Julien; Denoeud, France; Antonarakis, Stylianos; Ashburner, Michael; Bajic, Vladimir B; Birney, Ewan; Castelo, Robert; Eyras, Eduardo; Ucla, Catherine; Gingeras, Thomas R; Harrow, Jennifer; Hubbard, Tim; Lewis, Suzanna E; Reese, Martin G
2006-01-01
Background We present the results of EGASP, a community experiment to assess the state-of-the-art in genome annotation within the ENCODE regions, which span 1% of the human genome sequence. The experiment had two major goals: the assessment of the accuracy of computational methods to predict protein coding genes; and the overall assessment of the completeness of the current human genome annotations as represented in the ENCODE regions. For the computational prediction assessment, eighteen groups contributed gene predictions. We evaluated these submissions against each other based on a 'reference set' of annotations generated as part of the GENCODE project. These annotations were not available to the prediction groups prior to the submission deadline, so that their predictions were blind and an external advisory committee could perform a fair assessment. Results The best methods had at least one gene transcript correctly predicted for close to 70% of the annotated genes. Nevertheless, the multiple transcript accuracy, taking into account alternative splicing, reached only approximately 40% to 50% accuracy. At the coding nucleotide level, the best programs reached an accuracy of 90% in both sensitivity and specificity. Programs relying on mRNA and protein sequences were the most accurate in reproducing the manually curated annotations. Experimental validation shows that only a very small percentage (3.2%) of the selected 221 computationally predicted exons outside of the existing annotation could be verified. Conclusion This is the first such experiment in human DNA, and we have followed the standards established in a similar experiment, GASP1, in Drosophila melanogaster. We believe the results presented here contribute to the value of ongoing large-scale annotation projects and should guide further experimental methods when being scaled up to the entire human genome sequence. PMID:16925836
NASA Technical Reports Server (NTRS)
Maskew, B.
1982-01-01
VSAERO is a computer program used to predict the nonlinear aerodynamic characteristics of arbitrary three-dimensional configurations in subsonic flow. Nonlinear effects of vortex separation and vortex surface interaction are treated in an iterative wake-shape calculation procedure, while the effects of viscosity are treated in an iterative loop coupling potential-flow and integral boundary-layer calculations. The program employs a surface singularity panel method using quadrilateral panels on which doublet and source singularities are distributed in a piecewise constant form. This user's manual provides a brief overview of the mathematical model, instructions for configuration modeling and a description of the input and output data. A listing of a sample case is included.
NASA Technical Reports Server (NTRS)
Sawyer, W. C.; Allen, J. M.; Hernandez, G.; Dillenius, M. F. E.; Hemsch, M. J.
1982-01-01
This paper presents a survey of engineering computational methods and experimental programs used for estimating the aerodynamic characteristics of missile configurations. Emphasis is placed on those methods which are suitable for preliminary design of conventional and advanced concepts. An analysis of the technical approaches of the various methods is made in order to assess their suitability to estimate longitudinal and/or lateral-directional characteristics for different classes of missile configurations. Some comparisons between the predicted characteristics and experimental data are presented. These comparisons are made for a large variation in flow conditions and model attitude parameters. The paper also presents known experimental research programs developed for the specific purpose of validating analytical methods and extending the capability of data-base programs.
NASA Technical Reports Server (NTRS)
Wieber, P. R.
1973-01-01
A numerical program was developed to compute transient compressible and incompressible laminar flows in two dimensions with multicomponent mixing and chemical reaction. The algorithm used the Los Alamos Scientific Laboratory ICE (Implicit Continuous-Fluid Eulerian) method as its base. The program can compute both high and low speed compressible flows. The numerical program incorporating the stabilization techniques was quite successful in treating both old and new problems. Detailed calculations of coaxial flow very close to the entry plane were possible. The program treated complex flows such as the formation and downstream growth of a recirculation cell. An implicit solution of the species equation predicted mixing and reaction rates which compared favorably with the literature.
Structural analysis of cylindrical thrust chambers, volume 3
NASA Technical Reports Server (NTRS)
Pearson, M. L.
1981-01-01
A system of three computer programs is described for use in conjunction with the BOPAGE finite element program. The programs are demonstrated by analyzing cumulative plastic deformation in a regeneratively cooled rocket thrust chamber. The codes provide the capability to predict geometric and material nonlinear behavior of cyclically loaded structures without performing a cycle-by-cycle analysis over the life of the structure. The program set consists of a BOPACE restart tape reader routine, and extrapolation program and a plot package.
Predicting introductory programming performance: A multi-institutional multivariate study
NASA Astrophysics Data System (ADS)
Bergin, Susan; Reilly, Ronan
2006-12-01
A model for predicting student performance on introductory programming modules is presented. The model uses attributes identified in a study carried out at four third-level institutions in the Republic of Ireland. Four instruments were used to collect the data and over 25 attributes were examined. A data reduction technique was applied and a logistic regression model using 10-fold stratified cross validation was developed. The model used three attributes: Leaving Certificate Mathematics result (final mathematics examination at second level), number of hours playing computer games while taking the module and programming self-esteem. Prediction success was significant with 80% of students correctly classified. The model also works well on a per-institution level. A discussion on the implications of the model is provided and future work is outlined.
[A prediction model for internet game addiction in adolescents: using a decision tree analysis].
Kim, Ki Sook; Kim, Kyung Hee
2010-06-01
This study was designed to build a theoretical frame to provide practical help to prevent and manage adolescent internet game addiction by developing a prediction model through a comprehensive analysis of related factors. The participants were 1,318 students studying in elementary, middle, and high schools in Seoul and Gyeonggi Province, Korea. Collected data were analyzed using the SPSS program. Decision Tree Analysis using the Clementine program was applied to build an optimum and significant prediction model to predict internet game addiction related to various factors, especially parent related factors. From the data analyses, the prediction model for factors related to internet game addiction presented with 5 pathways. Causative factors included gender, type of school, siblings, economic status, religion, time spent alone, gaming place, payment to Internet café, frequency, duration, parent's ability to use internet, occupation (mother), trust (father), expectations regarding adolescent's study (mother), supervising (both parents), rearing attitude (both parents). The results suggest preventive and managerial nursing programs for specific groups by path. Use of this predictive model can expand the role of school nurses, not only in counseling addicted adolescents but also, in developing and carrying out programs with parents and approaching adolescents individually through databases and computer programming.
The goal of chemical toxicology research is utilizing short term bioassays and/or robust computational methods to predict in vivo toxicity endpoints for chemicals. The ToxCast program established at the US Environmental Protection Agency (EPA) is addressing this goal by using ca....
A research program in empirical computer science
NASA Technical Reports Server (NTRS)
Knight, J. C.
1991-01-01
During the grant reporting period our primary activities have been to begin preparation for the establishment of a research program in experimental computer science. The focus of research in this program will be safety-critical systems. Many questions that arise in the effort to improve software dependability can only be addressed empirically. For example, there is no way to predict the performance of the various proposed approaches to building fault-tolerant software. Performance models, though valuable, are parameterized and cannot be used to make quantitative predictions without experimental determination of underlying distributions. In the past, experimentation has been able to shed some light on the practical benefits and limitations of software fault tolerance. It is common, also, for experimentation to reveal new questions or new aspects of problems that were previously unknown. A good example is the Consistent Comparison Problem that was revealed by experimentation and subsequently studied in depth. The result was a clear understanding of a previously unknown problem with software fault tolerance. The purpose of a research program in empirical computer science is to perform controlled experiments in the area of real-time, embedded control systems. The goal of the various experiments will be to determine better approaches to the construction of the software for computing systems that have to be relied upon. As such it will validate research concepts from other sources, provide new research results, and facilitate the transition of research results from concepts to practical procedures that can be applied with low risk to NASA flight projects. The target of experimentation will be the production software development activities undertaken by any organization prepared to contribute to the research program. Experimental goals, procedures, data analysis and result reporting will be performed for the most part by the University of Virginia.
DOE Office of Scientific and Technical Information (OSTI.GOV)
McCoy, Michel; Archer, Bill; Hendrickson, Bruce
The Stockpile Stewardship Program (SSP) is an integrated technical program for maintaining the safety, surety, and reliability of the U.S. nuclear stockpile. The SSP uses nuclear test data, computational modeling and simulation, and experimental facilities to advance understanding of nuclear weapons. It includes stockpile surveillance, experimental research, development and engineering programs, and an appropriately scaled production capability to support stockpile requirements. This integrated national program requires the continued use of experimental facilities and programs, and the computational capabilities to support these programs. The Advanced Simulation and Computing Program (ASC) is a cornerstone of the SSP, providing simulation capabilities and computationalmore » resources that support annual stockpile assessment and certification, study advanced nuclear weapons design and manufacturing processes, analyze accident scenarios and weapons aging, and provide the tools to enable stockpile Life Extension Programs (LEPs) and the resolution of Significant Finding Investigations (SFIs). This requires a balance of resource, including technical staff, hardware, simulation software, and computer science solutions. ASC is now focused on increasing predictive capabilities in a three-dimensional (3D) simulation environment while maintaining support to the SSP. The program continues to improve its unique tools for solving progressively more difficult stockpile problems (sufficient resolution, dimensionality, and scientific details), and quantifying critical margins and uncertainties. Resolving each issue requires increasingly difficult analyses because the aging process has progressively moved the stockpile further away from the original test base. Where possible, the program also enables the use of high performance computing (HPC) and simulation tools to address broader national security needs, such as foreign nuclear weapon assessments and counter nuclear terrorism.« less
EPA is developing methods for utilizing computational chemistry, high-throughput screening (HTS)and genomic technologies to predict potential toxicity and prioritize the use of limited testing resources.
Deciu, Cosmin; Sun, Jun; Wall, Mark A
2007-09-01
We discuss several aspects related to load balancing of database search jobs in a distributed computing environment, such as Linux cluster. Load balancing is a technique for making the most of multiple computational resources, which is particularly relevant in environments in which the usage of such resources is very high. The particular case of the Sequest program is considered here, but the general methodology should apply to any similar database search program. We show how the runtimes for Sequest searches of tandem mass spectral data can be predicted from profiles of previous representative searches, and how this information can be used for better load balancing of novel data. A well-known heuristic load balancing method is shown to be applicable to this problem, and its performance is analyzed for a variety of search parameters.
Survey of NASA research on crash dynamics
NASA Technical Reports Server (NTRS)
Thomson, R. G.; Carden, H. D.; Hayduk, R. J.
1984-01-01
Ten years of structural crash dynamics research activities conducted on general aviation aircraft by the National Aeronautics and Space Administration (NASA) are described. Thirty-two full-scale crash tests were performed at Langley Research Center, and pertinent data on airframe and seat behavior were obtained. Concurrent with the experimental program, analytical methods were developed to help predict structural behavior during impact. The effects of flight parameters at impact on cabin deceleration pulses at the seat/occupant interface, experimental and analytical correlation of data on load-limiting subfloor and seat configurations, airplane section test results for computer modeling validation, and data from emergency-locator-transmitter (ELT) investigations to determine probable cause of false alarms and nonactivations are assessed. Computer programs which provide designers with analytical methods for predicting accelerations, velocities, and displacements of collapsing structures are also discussed.
System model development for nuclear thermal propulsion
NASA Technical Reports Server (NTRS)
Walton, James T.; Hannan, Nelson A.; Perkins, Ken R.; Buksa, John H.; Worley, Brian A.; Dobranich, Dean
1992-01-01
A critical enabling technology in the evolutionary development of nuclear thermal propulsion (NTP) is the ability to predict the system performance under a variety of operating conditions. This is crucial for mission analysis and for control subsystem testing as well as for the modeling of various failure modes. Performance must be accurately predicted during steady-state and transient operation, including startup, shutdown, and post operation cooling. The development and application of verified and validated system models has the potential to reduce the design, testing, and cost and time required for the technology to reach flight-ready status. Since Oct. 1991, the U.S. Department of Energy (DOE), Department of Defense (DOD), and NASA have initiated critical technology development efforts for NTP systems to be used on Space Exploration Initiative (SEI) missions to the Moon and Mars. This paper presents the strategy and progress of an interagency NASA/DOE/DOD team for NTP system modeling. It is the intent of the interagency team to develop several levels of computer programs to simulate various NTP systems. The first level will provide rapid, parameterized calculations of overall system performance. Succeeding computer programs will provide analysis of each component in sufficient detail to guide the design teams and experimental efforts. The computer programs will allow simulation of the entire system to allow prediction of the integrated performance. An interagency team was formed for this task to use the best capabilities available and to assure appropriate peer review.
Modular Engine Noise Component Prediction System (MCP) Program Users' Guide
NASA Technical Reports Server (NTRS)
Golub, Robert A. (Technical Monitor); Herkes, William H.; Reed, David H.
2004-01-01
This is a user's manual for Modular Engine Noise Component Prediction System (MCP). This computer code allows the user to predict turbofan engine noise estimates. The program is based on an empirical procedure that has evolved over many years at The Boeing Company. The data used to develop the procedure include both full-scale engine data and small-scale model data, and include testing done by Boeing, by the engine manufacturers, and by NASA. In order to generate a noise estimate, the user specifies the appropriate engine properties (including both geometry and performance parameters), the microphone locations, the atmospheric conditions, and certain data processing options. The version of the program described here allows the user to predict three components: inlet-radiated fan noise, aft-radiated fan noise, and jet noise. MCP predicts one-third octave band noise levels over the frequency range of 50 to 10,000 Hertz. It also calculates overall sound pressure levels and certain subjective noise metrics (e.g., perceived noise levels).
Three-dimensional transonic potential flow about complex 3-dimensional configurations
NASA Technical Reports Server (NTRS)
Reyhner, T. A.
1984-01-01
An analysis has been developed and a computer code written to predict three-dimensional subsonic or transonic potential flow fields about lifting or nonlifting configurations. Possible condfigurations include inlets, nacelles, nacelles with ground planes, S-ducts, turboprop nacelles, wings, and wing-pylon-nacelle combinations. The solution of the full partial differential equation for compressible potential flow written in terms of a velocity potential is obtained using finite differences, line relaxation, and multigrid. The analysis uses either a cylindrical or Cartesian coordinate system. The computational mesh is not body fitted. The analysis has been programmed in FORTRAN for both the CDC CYBER 203 and the CRAY-1 computers. Comparisons of computed results with experimental measurement are presented. Descriptions of the program input and output formats are included.
Status of Computational Aerodynamic Modeling Tools for Aircraft Loss-of-Control
NASA Technical Reports Server (NTRS)
Frink, Neal T.; Murphy, Patrick C.; Atkins, Harold L.; Viken, Sally A.; Petrilli, Justin L.; Gopalarathnam, Ashok; Paul, Ryan C.
2016-01-01
A concerted effort has been underway over the past several years to evolve computational capabilities for modeling aircraft loss-of-control under the NASA Aviation Safety Program. A principal goal has been to develop reliable computational tools for predicting and analyzing the non-linear stability & control characteristics of aircraft near stall boundaries affecting safe flight, and for utilizing those predictions for creating augmented flight simulation models that improve pilot training. Pursuing such an ambitious task with limited resources required the forging of close collaborative relationships with a diverse body of computational aerodynamicists and flight simulation experts to leverage their respective research efforts into the creation of NASA tools to meet this goal. Considerable progress has been made and work remains to be done. This paper summarizes the status of the NASA effort to establish computational capabilities for modeling aircraft loss-of-control and offers recommendations for future work.
Tonkin, M.J.; Hill, Mary C.; Doherty, John
2003-01-01
This document describes the MOD-PREDICT program, which helps evaluate userdefined sets of observations, prior information, and predictions, using the ground-water model MODFLOW-2000. MOD-PREDICT takes advantage of the existing Observation and Sensitivity Processes (Hill and others, 2000) by initiating runs of MODFLOW-2000 and using the output files produced. The names and formats of the MODFLOW-2000 input files are unchanged, such that full backward compatibility is maintained. A new name file and input files are required for MOD-PREDICT. The performance of MOD-PREDICT has been tested in a variety of applications. Future applications, however, might reveal errors that were not detected in the test simulations. Users are requested to notify the U.S. Geological Survey of any errors found in this document or the computer program using the email address available at the web address below. Updates might occasionally be made to this document, to the MOD-PREDICT program, and to MODFLOW- 2000. Users can check for updates on the Internet at URL http://water.usgs.gov/software/ground water.html/.
Orbital Maneuvering Engine Feed System Coupled Stability Investigation, Computer User's Manual
NASA Technical Reports Server (NTRS)
Schuman, M. D.; Fertig, K. W.; Hunting, J. K.; Kahn, D. R.
1975-01-01
An operating manual for the feed system coupled stability model was given, in partial fulfillment of a program designed to develop, verify, and document a digital computer model that can be used to analyze and predict engine/feed system coupled instabilities in pressure-fed storable propellant propulsion systems over a frequency range of 10 to 1,000 Hz. The first section describes the analytical approach to modelling the feed system hydrodynamics, combustion dynamics, chamber dynamics, and overall engineering model structure, and presents the governing equations in each of the technical areas. This is followed by the program user's guide, which is a complete description of the structure and operation of the computerized model. Last, appendices provide an alphabetized FORTRAN symbol table, detailed program logic diagrams, computer code listings, and sample case input and output data listings.
NASA Technical Reports Server (NTRS)
Mehrotra, S. C.; Lan, C. E.
1978-01-01
The necessary information for using a computer program to predict distributed and total aerodynamic characteristics for low aspect ratio wings with partial leading-edge separation is presented. The flow is assumed to be steady and inviscid. The wing boundary condition is formulated by the Quasi-Vortex-Lattice method. The leading edge separated vortices are represented by discrete free vortex elements which are aligned with the local velocity vector at midpoints to satisfy the force free condition. The wake behind the trailing edge is also force free. The flow tangency boundary condition is satisfied on the wing, including the leading and trailing edges. The program is restricted to delta wings with zero thickness and no camber. It is written in FORTRAN language and runs on CDC 6600 computer.
The nature and use of prediction skills in a biological computer simulation
NASA Astrophysics Data System (ADS)
Lavoie, Derrick R.; Good, Ron
The primary goal of this study was to examine the science process skill of prediction using qualitative research methodology. The think-aloud interview, modeled after Ericsson and Simon (1984), let to the identification of 63 program exploration and prediction behaviors.The performance of seven formal and seven concrete operational high-school biology students were videotaped during a three-phase learning sequence on water pollution. Subjects explored the effects of five independent variables on two dependent variables over time using a computer-simulation program. Predictions were made concerning the effect of the independent variables upon dependent variables through time. Subjects were identified according to initial knowledge of the subject matter and success at solving three selected prediction problems.Successful predictors generally had high initial knowledge of the subject matter and were formal operational. Unsuccessful predictors generally had low initial knowledge and were concrete operational. High initial knowledge seemed to be more important to predictive success than stage of Piagetian cognitive development.Successful prediction behaviors involved systematic manipulation of the independent variables, note taking, identification and use of appropriate independent-dependent variable relationships, high interest and motivation, and in general, higher-level thinking skills. Behaviors characteristic of unsuccessful predictors were nonsystematic manipulation of independent variables, lack of motivation and persistence, misconceptions, and the identification and use of inappropriate independent-dependent variable relationships.
Computer program for analysis of coupled-cavity traveling wave tubes
NASA Technical Reports Server (NTRS)
Connolly, D. J.; Omalley, T. A.
1977-01-01
A flexible, accurate, large signal computer program was developed for the design of coupled cavity traveling wave tubes. The program is written in FORTRAN IV for an IBM 360/67 time sharing system. The beam is described by a disk model and the slow wave structure by a sequence of cavities, or cells. The computational approach is arranged so that each cavity may have geometrical or electrical parameters different from those of its neighbors. This allows the program user to simulate a tube of almost arbitrary complexity. Input and output couplers, severs, complicated velocity tapers, and other features peculiar to one or a few cavities may be modeled by a correct choice of input data. The beam-wave interaction is handled by an approach in which the radio frequency fields are expanded in solutions to the transverse magnetic wave equation. All significant space harmonics are retained. The program was used to perform a design study of the traveling-wave tube developed for the Communications Technology Satellite. Good agreement was obtained between the predictions of the program and the measured performance of the flight tube.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Fiveland, W.A.; Oberjohn, W.J.; Cornelius, D.K.
1985-12-01
This report summarizes the work conducted during a 30-month contract with the United States Department of Energy (DOE) Pittsburgh Energy Technology Center (PETC). The general objective is to develop and verify a computer code capable of modeling the major aspects of pulverized coal combustion. Achieving this objective will lead to design methods applicable to industrial and utility furnaces. The combustion model (COMO) is based mainly on an existing Babcock and Wilcox (B and W) computer program. The model consists of a number of relatively independent modules that represent the major processes involved in pulverized coal combustion: flow, heterogeneous and homogeneousmore » chemical reaction, and heat transfer. As models are improved or as new ones are developed, this modular structure allows portions of the COMO model to be updated with minimal impact on the remainder of the program. The report consists of two volumes. This volume (Volume 1) contains a technical summary of the COMO model, results of predictions for gas phase combustion, pulverized coal combustion, and a detailed description of the COMO model. Volume 2 is the Users Guide for COMO and contains detailed instructions for preparing the input data and a description of the program output. Several example cases have been included to aid the user in usage of the computer program for pulverized coal applications. 66 refs., 41 figs., 21 tabs.« less
Progress and challenges in bioinformatics approaches for enhancer identification
Kleftogiannis, Dimitrios; Kalnis, Panos
2016-01-01
Enhancers are cis-acting DNA elements that play critical roles in distal regulation of gene expression. Identifying enhancers is an important step for understanding distinct gene expression programs that may reflect normal and pathogenic cellular conditions. Experimental identification of enhancers is constrained by the set of conditions used in the experiment. This requires multiple experiments to identify enhancers, as they can be active under specific cellular conditions but not in different cell types/tissues or cellular states. This has opened prospects for computational prediction methods that can be used for high-throughput identification of putative enhancers to complement experimental approaches. Potential functions and properties of predicted enhancers have been catalogued and summarized in several enhancer-oriented databases. Because the current methods for the computational prediction of enhancers produce significantly different enhancer predictions, it will be beneficial for the research community to have an overview of the strategies and solutions developed in this field. In this review, we focus on the identification and analysis of enhancers by bioinformatics approaches. First, we describe a general framework for computational identification of enhancers, present relevant data types and discuss possible computational solutions. Next, we cover over 30 existing computational enhancer identification methods that were developed since 2000. Our review highlights advantages, limitations and potentials, while suggesting pragmatic guidelines for development of more efficient computational enhancer prediction methods. Finally, we discuss challenges and open problems of this topic, which require further consideration. PMID:26634919
Prospective estimation of organ dose in CT under tube current modulation
DOE Office of Scientific and Technical Information (OSTI.GOV)
Tian, Xiaoyu, E-mail: xt3@duke.edu; Li, Xiang; Segars, W. Paul
Purpose: Computed tomography (CT) has been widely used worldwide as a tool for medical diagnosis and imaging. However, despite its significant clinical benefits, CT radiation dose at the population level has become a subject of public attention and concern. In this light, optimizing radiation dose has become a core responsibility for the CT community. As a fundamental step to manage and optimize dose, it may be beneficial to have accurate and prospective knowledge about the radiation dose for an individual patient. In this study, the authors developed a framework to prospectively estimate organ dose for chest and abdominopelvic CT examsmore » under tube current modulation (TCM). Methods: The organ dose is mainly dependent on two key factors: patient anatomy and irradiation field. A prediction process was developed to accurately model both factors. To model the anatomical diversity and complexity in the patient population, the authors used a previously developed library of computational phantoms with broad distributions of sizes, ages, and genders. A selected clinical patient, represented by a computational phantom in the study, was optimally matched with another computational phantom in the library to obtain a representation of the patient’s anatomy. To model the irradiation field, a previously validated Monte Carlo program was used to model CT scanner systems. The tube current profiles were modeled using a ray-tracing program as previously reported that theoretically emulated the variability of modulation profiles from major CT machine manufacturers Li et al., [Phys. Med. Biol. 59, 4525–4548 (2014)]. The prediction of organ dose was achieved using the following process: (1) CTDI{sub vol}-normalized-organ dose coefficients (h{sub organ}) for fixed tube current were first estimated as the prediction basis for the computational phantoms; (2) each computation phantom, regarded as a clinical patient, was optimally matched with one computational phantom in the library; (3) to account for the effect of the TCM scheme, a weighted organ-specific CTDI{sub vol} [denoted as (CTDI{sub vol}){sub organ,weighted}] was computed for each organ based on the TCM profile and the anatomy of the “matched” phantom; (4) the organ dose was predicted by multiplying the weighted organ-specific CTDI{sub vol} with the organ dose coefficients (h{sub organ}). To quantify the prediction accuracy, each predicted organ dose was compared with the corresponding organ dose simulated from the Monte Carlo program with the TCM profile explicitly modeled. Results: The predicted organ dose showed good agreements with the simulated organ dose across all organs and modulation profiles. The average percentage error in organ dose estimation was generally within 20% across all organs and modulation profiles, except for organs located in the pelvic and shoulder regions. For an average CTDI{sub vol} of a CT exam of 10 mGy, the average error at full modulation strength (α = 1) across all organs was 0.91 mGy for chest exams, and 0.82 mGy for abdominopelvic exams. Conclusions: This study developed a quantitative model to predict organ dose for clinical chest and abdominopelvic scans. Such information may aid in the design of optimized CT protocols in relation to a targeted level of image quality.« less
Lossless Compression of Data into Fixed-Length Packets
NASA Technical Reports Server (NTRS)
Kiely, Aaron B.; Klimesh, Matthew A.
2009-01-01
A computer program effects lossless compression of data samples from a one-dimensional source into fixed-length data packets. The software makes use of adaptive prediction: it exploits the data structure in such a way as to increase the efficiency of compression beyond that otherwise achievable. Adaptive linear filtering is used to predict each sample value based on past sample values. The difference between predicted and actual sample values is encoded using a Golomb code.
Chen, Ruoying; Zhang, Zhiwang; Wu, Di; Zhang, Peng; Zhang, Xinyang; Wang, Yong; Shi, Yong
2011-01-21
Protein-protein interactions are fundamentally important in many biological processes and it is in pressing need to understand the principles of protein-protein interactions. Mutagenesis studies have found that only a small fraction of surface residues, known as hot spots, are responsible for the physical binding in protein complexes. However, revealing hot spots by mutagenesis experiments are usually time consuming and expensive. In order to complement the experimental efforts, we propose a new computational approach in this paper to predict hot spots. Our method, Rough Set-based Multiple Criteria Linear Programming (RS-MCLP), integrates rough sets theory and multiple criteria linear programming to choose dominant features and computationally predict hot spots. Our approach is benchmarked by a dataset of 904 alanine-mutated residues and the results show that our RS-MCLP method performs better than other methods, e.g., MCLP, Decision Tree, Bayes Net, and the existing HotSprint database. In addition, we reveal several biological insights based on our analysis. We find that four features (the change of accessible surface area, percentage of the change of accessible surface area, size of a residue, and atomic contacts) are critical in predicting hot spots. Furthermore, we find that three residues (Tyr, Trp, and Phe) are abundant in hot spots through analyzing the distribution of amino acids. Copyright © 2010 Elsevier Ltd. All rights reserved.
The FITS model office ergonomics program: a model for best practice.
Chim, Justine M Y
2014-01-01
An effective office ergonomics program can predict positive results in reducing musculoskeletal injury rates, enhancing productivity, and improving staff well-being and job satisfaction. Its objective is to provide a systematic solution to manage the potential risk of musculoskeletal disorders among computer users in an office setting. A FITS Model office ergonomics program is developed. The FITS Model Office Ergonomics Program has been developed which draws on the legislative requirements for promoting the health and safety of workers using computers for extended periods as well as previous research findings. The Model is developed according to the practical industrial knowledge in ergonomics, occupational health and safety management, and human resources management in Hong Kong and overseas. This paper proposes a comprehensive office ergonomics program, the FITS Model, which considers (1) Furniture Evaluation and Selection; (2) Individual Workstation Assessment; (3) Training and Education; (4) Stretching Exercises and Rest Break as elements of an effective program. An experienced ergonomics practitioner should be included in the program design and implementation. Through the FITS Model Office Ergonomics Program, the risk of musculoskeletal disorders among computer users can be eliminated or minimized, and workplace health and safety and employees' wellness enhanced.
ERIC Educational Resources Information Center
Alty, James L.
Dual Coding Theory has quite specific predictions about how information in different media is stored, manipulated and recalled. Different combinations of media are expected to have significant effects upon the recall and retention of information. This obviously may have important consequences in the design of computer-based programs. The paper…
NASA Technical Reports Server (NTRS)
Blair, M. F.
1991-01-01
A combined experimental and computational program was conducted to examine the heat transfer distribution in a turbine rotor passage geometrically similar to the Space Shuttle Main Engine (SSME) High Pressure Fuel Turbopump (HPFTP). Heat transfer was measured and computed for both the full span suction and pressure surfaces of the rotor airfoil as well as for the hub endwall surface. The objective of the program was to provide a benchmark-quality database for the assessment of rotor heat transfer computational techniques. The experimental portion of the study was conducted in a large scale, ambient temperature, rotating turbine model. The computational portion consisted of the application of a well-posed parabolized Navier-Stokes analysis of the calculation of the three-dimensional viscous flow through ducts simulating a gas turbine package. The results of this assessment indicate that the procedure has the potential to predict the aerodynamics and the heat transfer in a gas turbine passage and can be used to develop detailed three dimensional turbulence models for the prediction of skin friction and heat transfer in complex three dimensional flow passages.
Aeroelastic Analysis for Rotorcraft
NASA Technical Reports Server (NTRS)
Johnson, W.
1982-01-01
Aeroelastic-analysis computer program incorporates an analytical model of aeroelastic behavior of wide range of rotorcraft. Such an analytical model is desirable for both pretest predictions and posttest correlations. Program can be applied in investigations of isolated rotor aeroelasticity and helicopter-flight dynamics and could be employed as basis for more-extensive investigations or aeroelastic behavior, such as automatic control system design.
Program For Optimization Of Nuclear Rocket Engines
NASA Technical Reports Server (NTRS)
Plebuch, R. K.; Mcdougall, J. K.; Ridolphi, F.; Walton, James T.
1994-01-01
NOP is versatile digital-computer program devoloped for parametric analysis of beryllium-reflected, graphite-moderated nuclear rocket engines. Facilitates analysis of performance of engine with respect to such considerations as specific impulse, engine power, type of engine cycle, and engine-design constraints arising from complications of fuel loading and internal gradients of temperature. Predicts minimum weight for specified performance.
Leonidas G. Lavdas
1996-01-01
This is a users manual for VSMOKE, a computer porgram for predicting the smoke and dry weather visibility impact of a singel prescvribed fire at several downwind locations. VSMOKE is a FORTRAN 77 program that depends on the input in file VSMOKE.IPT to generate output in file compatible with those used by the U.S. Environmental Protection Agency. VSMOKE is uniquely...
An exploratory investigation of weight estimation techniques for hypersonic flight vehicles
NASA Technical Reports Server (NTRS)
Cook, E. L.
1981-01-01
The three basic methods of weight prediction (fixed-fraction, statistical correlation, and point stress analysis) and some of the computer programs that have been developed to implement them are discussed. A modified version of the WAATS (Weights Analysis of Advanced Transportation Systems) program is presented, along with input data forms and an example problem.
Maximum likelihood convolutional decoding (MCD) performance due to system losses
NASA Technical Reports Server (NTRS)
Webster, L.
1976-01-01
A model for predicting the computational performance of a maximum likelihood convolutional decoder (MCD) operating in a noisy carrier reference environment is described. This model is used to develop a subroutine that will be utilized by the Telemetry Analysis Program to compute the MCD bit error rate. When this computational model is averaged over noisy reference phase errors using a high-rate interpolation scheme, the results are found to agree quite favorably with experimental measurements.
NASA Technical Reports Server (NTRS)
Zorumski, W. E.
1983-01-01
Analytic propeller noise prediction involves a sequence of computations culminating in the application of acoustic equations. The prediction sequence currently used by NASA in its ANOPP (aircraft noise prediction) program is described. The elements of the sequence are called program modules. The first group of modules analyzes the propeller geometry, the aerodynamics, including both potential and boundary layer flow, the propeller performance, and the surface loading distribution. This group of modules is based entirely on aerodynamic strip theory. The next group of modules deals with the actual noise prediction, based on data from the first group. Deterministic predictions of periodic thickness and loading noise are made using Farassat's time-domain methods. Broadband noise is predicted by the semi-empirical Schlinker-Amiet method. Near-field predictions of fuselage surface pressures include the effects of boundary layer refraction and (for a cylinder) scattering. Far-field predictions include atmospheric and ground effects. Experimental data from subsonic and transonic propellers are compared and NASA's future direction is propeller noise technology development are indicated.
Activity computer program for calculating ion irradiation activation
NASA Astrophysics Data System (ADS)
Palmer, Ben; Connolly, Brian; Read, Mark
2017-07-01
A computer program, Activity, was developed to predict the activity and gamma lines of materials irradiated with an ion beam. It uses the TENDL (Koning and Rochman, 2012) [1] proton reaction cross section database, the Stopping and Range of Ions in Matter (SRIM) (Biersack et al., 2010) code, a Nuclear Data Services (NDS) radioactive decay database (Sonzogni, 2006) [2] and an ENDF gamma decay database (Herman and Chadwick, 2006) [3]. An extended version of Bateman's equation is used to calculate the activity at time t, and this equation is solved analytically, with the option to also solve by numeric inverse Laplace Transform as a failsafe. The program outputs the expected activity and gamma lines of the activated material.
NASA Technical Reports Server (NTRS)
Wu, R. W.; Witmer, E. A.
1972-01-01
A user-oriented FORTRAN 4 computer program, called JET 3, is presented. The JET 3 program, which employs the spatial finite-element and timewise finite-difference method, can be used to predict the large two-dimensional elastic-plastic transient Kirchhoff-type deformations of a complete or partial structural ring, with various support conditions and restraints, subjected to a variety of initial velocity distributions and externally-applied transient forcing functions. The geometric shapes of the structural ring can be circular or arbitrarily curved and with variable thickness. Strain-hardening and strain-rate effects of the material are taken into account.
Interfacing comprehensive rotorcraft analysis with advanced aeromechanics and vortex wake models
NASA Astrophysics Data System (ADS)
Liu, Haiying
This dissertation describes three aspects of the comprehensive rotorcraft analysis. First, a physics-based methodology for the modeling of hydraulic devices within multibody-based comprehensive models of rotorcraft systems is developed. This newly proposed approach can predict the fully nonlinear behavior of hydraulic devices, and pressure levels in the hydraulic chambers are coupled with the dynamic response of the system. The proposed hydraulic device models are implemented in a multibody code and calibrated by comparing their predictions with test bench measurements for the UH-60 helicopter lead-lag damper. Predicted peak damping forces were found to be in good agreement with measurements, while the model did not predict the entire time history of damper force to the same level of accuracy. The proposed model evaluates relevant hydraulic quantities such as chamber pressures, orifice flow rates, and pressure relief valve displacements. This model could be used to design lead-lag dampers with desirable force and damping characteristics. The second part of this research is in the area of computational aeroelasticity, in which an interface between computational fluid dynamics (CFD) and computational structural dynamics (CSD) is established. This interface enables data exchange between CFD and CSD with the goal of achieving accurate airloads predictions. In this work, a loose coupling approach based on the delta-airloads method is developed in a finite-element method based multibody dynamics formulation, DYMORE. To validate this aerodynamic interface, a CFD code, OVERFLOW-2, is loosely coupled with a CSD program, DYMORE, to compute the airloads of different flight conditions for Sikorsky UH-60 aircraft. This loose coupling approach has good convergence characteristics. The predicted airloads are found to be in good agreement with the experimental data, although not for all flight conditions. In addition, the tight coupling interface between the CFD program, OVERFLOW-2, and the CSD program, DYMORE, is also established. The ability to accurately capture the wake structure around a helicopter rotor is crucial for rotorcraft performance analysis. In the third part of this thesis, a new representation of the wake vortex structure based on Non-Uniform Rational B-Spline (NURBS) curves and surfaces is proposed to develop an efficient model for prescribed and free wakes. NURBS curves and surfaces are able to represent complex shapes with remarkably little data. The proposed formulation has the potential to reduce the computational cost associated with the use of Helmholtz's law and the Biot-Savart law when calculating the induced flow field around the rotor. An efficient free-wake analysis will considerably decrease the computational cost of comprehensive rotorcraft analysis, making the approach more attractive to routine use in industrial settings.
Kwon, Andrew T.; Chou, Alice Yi; Arenillas, David J.; Wasserman, Wyeth W.
2011-01-01
We performed a genome-wide scan for muscle-specific cis-regulatory modules (CRMs) using three computational prediction programs. Based on the predictions, 339 candidate CRMs were tested in cell culture with NIH3T3 fibroblasts and C2C12 myoblasts for capacity to direct selective reporter gene expression to differentiated C2C12 myotubes. A subset of 19 CRMs validated as functional in the assay. The rate of predictive success reveals striking limitations of computational regulatory sequence analysis methods for CRM discovery. Motif-based methods performed no better than predictions based only on sequence conservation. Analysis of the properties of the functional sequences relative to inactive sequences identifies nucleotide sequence composition can be an important characteristic to incorporate in future methods for improved predictive specificity. Muscle-related TFBSs predicted within the functional sequences display greater sequence conservation than non-TFBS flanking regions. Comparison with recent MyoD and histone modification ChIP-Seq data supports the validity of the functional regions. PMID:22144875
Computational structural mechanics for engine structures
NASA Technical Reports Server (NTRS)
Chamis, Christos C.
1988-01-01
The computational structural mechanics (CSM) program at Lewis encompasses the formulation and solution of structural mechanics problems and the development of integrated software systems to computationally simulate the performance, durability, and life of engine structures. It is structured to supplement, complement, and, whenever possible, replace costly experimental efforts. Specific objectives are to investigate unique advantages of parallel and multiprocessing for reformulating and solving structural mechanics and formulating and solving multidisciplinary mechanics and to develop integrated structural system computational simulators for predicting structural performance, evaluating newly developed methods, and identifying and prioritizing improved or missing methods.
Computational structural mechanics for engine structures
NASA Technical Reports Server (NTRS)
Chamis, Christos C.
1989-01-01
The computational structural mechanics (CSM) program at Lewis encompasses the formulation and solution of structural mechanics problems and the development of integrated software systems to computationally simulate the performance, durability, and life of engine structures. It is structured to supplement, complement, and, whenever possible, replace costly experimental efforts. Specific objectives are to investigate unique advantages of parallel and multiprocessing for reformulating and solving structural mechanics and formulating and solving multidisciplinary mechanics and to develop integrated structural system computational simulators for predicting structural performance, evaluating newly developed methods, and identifying and prioritizing improved or missing methods.
Computing Operating Characteristics Of Bearing/Shaft Systems
NASA Technical Reports Server (NTRS)
Moore, James D.
1996-01-01
SHABERTH computer program predicts operating characteristics of bearings in multibearing load-support system. Lubricated and nonlubricated bearings modeled. Calculates loads, torques, temperatures, and fatigue lives of ball and/or roller bearings on single shaft. Provides for analysis of reaction of system to termination of supply of lubricant to bearings and other lubricated mechanical elements. Valuable in design and analysis of shaft/bearing systems. Two versions of SHABERTH available. Cray version (LEW-14860), "Computing Thermal Performances Of Shafts and Bearings". IBM PC version (MFS-28818), written for IBM PC-series and compatible computers running MS-DOS.
Semi-Markov adjunction to the Computer-Aided Markov Evaluator (CAME)
NASA Technical Reports Server (NTRS)
Rosch, Gene; Hutchins, Monica A.; Leong, Frank J.; Babcock, Philip S., IV
1988-01-01
The rule-based Computer-Aided Markov Evaluator (CAME) program was expanded in its ability to incorporate the effect of fault-handling processes into the construction of a reliability model. The fault-handling processes are modeled as semi-Markov events and CAME constructs and appropriate semi-Markov model. To solve the model, the program outputs it in a form which can be directly solved with the Semi-Markov Unreliability Range Evaluator (SURE) program. As a means of evaluating the alterations made to the CAME program, the program is used to model the reliability of portions of the Integrated Airframe/Propulsion Control System Architecture (IAPSA 2) reference configuration. The reliability predictions are compared with a previous analysis. The results bear out the feasibility of utilizing CAME to generate appropriate semi-Markov models to model fault-handling processes.
Airfoil Vibration Dampers program
NASA Technical Reports Server (NTRS)
Cook, Robert M.
1991-01-01
The Airfoil Vibration Damper program has consisted of an analysis phase and a testing phase. During the analysis phase, a state-of-the-art computer code was developed, which can be used to guide designers in the placement and sizing of friction dampers. The use of this computer code was demonstrated by performing representative analyses on turbine blades from the High Pressure Oxidizer Turbopump (HPOTP) and High Pressure Fuel Turbopump (HPFTP) of the Space Shuttle Main Engine (SSME). The testing phase of the program consisted of performing friction damping tests on two different cantilever beams. Data from these tests provided an empirical check on the accuracy of the computer code developed in the analysis phase. Results of the analysis and testing showed that the computer code can accurately predict the performance of friction dampers. In addition, a valuable set of friction damping data was generated, which can be used to aid in the design of friction dampers, as well as provide benchmark test cases for future code developers.
Combustion of hydrogen injected into a supersonic airstream (the SHIP computer program)
NASA Technical Reports Server (NTRS)
Markatos, N. C.; Spalding, D. B.; Tatchell, D. G.
1977-01-01
The mathematical and physical basis of the SHIP computer program which embodies a finite-difference, implicit numerical procedure for the computation of hydrogen injected into a supersonic airstream at an angle ranging from normal to parallel to the airstream main flow direction is described. The physical hypotheses built into the program include: a two-equation turbulence model, and a chemical equilibrium model for the hydrogen-oxygen reaction. Typical results for equilibrium combustion are presented and exhibit qualitatively plausible behavior. The computer time required for a given case is approximately 1 minute on a CDC 7600 machine. A discussion of the assumption of parabolic flow in the injection region is given which suggests that improvement in calculation in this region could be obtained by use of the partially parabolic procedure of Pratap and Spalding. It is concluded that the technique described herein provides the basis for an efficient and reliable means for predicting the effects of hydrogen injection into supersonic airstreams and of its subsequent combustion.
User's Manual for Thermal Analysis Program of Axially Grooved Heat Pipe (HTGAP)
NASA Technical Reports Server (NTRS)
Kamotani, Y.
1978-01-01
A computer program that numerically predicts the steady state temperature distribution inside an axially grooved heat pipe wall for a given groove geometry and working fluid under various heat input and output modes is described. The program computes both evaporator and condenser film coefficients. The program is able to handle both axisymmetric and nonaxisymmetric heat transfer cases. Non-axisymmetric heat transfer results either from non-uniform input at the evaporator or non-uniform heat removal from the condenser, or from both. The presence of a liquid pool in the condenser region under one-g condition also causes non-axisymmetric heat transfer, and its effect on the pipe wall temperature distribution is included in the present program. The hydrodynamic aspect of an axially grooved heat pipe is studied in the Groove Analysis Program (GAP). The present thermal analysis program assumes that the GAP program (or other similar programs) is run first so that the heat transport limit and optimum fluid charge of the heat pipe are known a priori.
New PDS will predict performance of pallets made with used parts
John W. Clarke; Marshall S. White; Philip A. Araman
2001-01-01
The Pallet Design System (PDS) is a computer design program developed by Virginia Tech, the National Wooden Pallet & Container Association, and the U.S. Forest Service to quickly and accurately predict the performance of new wood pallets. PDS has been upgraded annually since its original version in 1984. All of the previous upgrades, however, have continued to...
Growth and Yield of Appalachian Mixed Hardwoods After Thinning
Wade C. Harrison; Harold E. Burkhart; Thomas E. Burk; Donald E. Beckand
1986-01-01
G-RAT (Growth of Hardwoods After Thinning) is a system of computer programs used to predict growth and yield of Appalachian mixed hardwoods after thinning. Given a tree list or stand table, along with inputs of stand age, site index, and stand basal area before thinning, G-RAT software uses species-specific individual tree equations to predict tree basal area...
Taper-based system for estimating stem volumes of upland oaks
Donald E. Hilt
1980-01-01
A taper-based system for estimating stem volumes is developed for Central States upland oaks. Inside bark diameters up the stem are predicted as a function of dbhib, total height, and powers and relative height. A Fortran IV computer program, OAKVOL, is used to predict cubic and board-foot volumes to any desired merchantable top dib. Volumes of...
NASTRAN application for the prediction of aircraft interior noise
NASA Technical Reports Server (NTRS)
Marulo, Francesco; Beyer, Todd B.
1987-01-01
The application of a structural-acoustic analogy within the NASTRAN finite element program for the prediction of aircraft interior noise is presented. Some refinements of the method, which reduce the amount of computation required for large, complex structures, are discussed. Also, further improvements are proposed and preliminary comparisons with structural and acoustic modal data obtained for a large, composite cylinder are presented.
ERIC Educational Resources Information Center
Kearney, Matthew; Treagust, David F.; Yeo, Shelley; Zadnik, Marjan G.
2001-01-01
Discusses student and teacher perceptions of a new development in the use of the predict-observe-explain (POE) strategy. This development involves the incorporation of POE tasks into a multimedia computer program that uses real-life, digital video clips of difficult, expensive, time consuming, or dangerous scenarios as stimuli for these tasks.…
Coupled rotor/airframe vibration analysis
NASA Technical Reports Server (NTRS)
Sopher, R.; Studwell, R. E.; Cassarino, S.; Kottapalli, S. B. R.
1982-01-01
A coupled rotor/airframe vibration analysis developed as a design tool for predicting helicopter vibrations and a research tool to quantify the effects of structural properties, aerodynamic interactions, and vibration reduction devices on vehicle vibration levels is described. The analysis consists of a base program utilizing an impedance matching technique to represent the coupled rotor/airframe dynamics of the system supported by inputs from several external programs supplying sophisticated rotor and airframe aerodynamic and structural dynamic representation. The theoretical background, computer program capabilities and limited correlation results are presented in this report. Correlation results using scale model wind tunnel results show that the analysis can adequately predict trends of vibration variations with airspeed and higher harmonic control effects. Predictions of absolute values of vibration levels were found to be very sensitive to modal characteristics and results were not representative of measured values.
NASA Technical Reports Server (NTRS)
Forssen, B.; Wang, Y. S.; Crocker, M. J.
1981-01-01
Several aspects were studied. The SEA theory was used to develop a theoretical model to predict the transmission loss through an aircraft window. This work mainly consisted of the writing of two computer programs. One program predicts the sound transmission through a plexiglass window (the case of a single partition). The other program applies to the case of a plexiglass window window with a window shade added (the case of a double partition with an air gap). The sound transmission through a structure was measured in experimental studies using several different methods in order that the accuracy and complexity of all the methods could be compared. Also, the measurements were conducted on the simple model of a fuselage (a cylindrical shell), on a real aircraft fuselage, and on stiffened panels.
NASA Astrophysics Data System (ADS)
Forssen, B.; Wang, Y. S.; Crocker, M. J.
1981-12-01
Several aspects were studied. The SEA theory was used to develop a theoretical model to predict the transmission loss through an aircraft window. This work mainly consisted of the writing of two computer programs. One program predicts the sound transmission through a plexiglass window (the case of a single partition). The other program applies to the case of a plexiglass window window with a window shade added (the case of a double partition with an air gap). The sound transmission through a structure was measured in experimental studies using several different methods in order that the accuracy and complexity of all the methods could be compared. Also, the measurements were conducted on the simple model of a fuselage (a cylindrical shell), on a real aircraft fuselage, and on stiffened panels.
Adeli, Hossein; Vitu, Françoise; Zelinsky, Gregory J
2017-02-08
Modern computational models of attention predict fixations using saliency maps and target maps, which prioritize locations for fixation based on feature contrast and target goals, respectively. But whereas many such models are biologically plausible, none have looked to the oculomotor system for design constraints or parameter specification. Conversely, although most models of saccade programming are tightly coupled to underlying neurophysiology, none have been tested using real-world stimuli and tasks. We combined the strengths of these two approaches in MASC, a model of attention in the superior colliculus (SC) that captures known neurophysiological constraints on saccade programming. We show that MASC predicted the fixation locations of humans freely viewing naturalistic scenes and performing exemplar and categorical search tasks, a breadth achieved by no other existing model. Moreover, it did this as well or better than its more specialized state-of-the-art competitors. MASC's predictive success stems from its inclusion of high-level but core principles of SC organization: an over-representation of foveal information, size-invariant population codes, cascaded population averaging over distorted visual and motor maps, and competition between motor point images for saccade programming, all of which cause further modulation of priority (attention) after projection of saliency and target maps to the SC. Only by incorporating these organizing brain principles into our models can we fully understand the transformation of complex visual information into the saccade programs underlying movements of overt attention. With MASC, a theoretical footing now exists to generate and test computationally explicit predictions of behavioral and neural responses in visually complex real-world contexts. SIGNIFICANCE STATEMENT The superior colliculus (SC) performs a visual-to-motor transformation vital to overt attention, but existing SC models cannot predict saccades to visually complex real-world stimuli. We introduce a brain-inspired SC model that outperforms state-of-the-art image-based competitors in predicting the sequences of fixations made by humans performing a range of everyday tasks (scene viewing and exemplar and categorical search), making clear the value of looking to the brain for model design. This work is significant in that it will drive new research by making computationally explicit predictions of SC neural population activity in response to naturalistic stimuli and tasks. It will also serve as a blueprint for the construction of other brain-inspired models, helping to usher in the next generation of truly intelligent autonomous systems. Copyright © 2017 the authors 0270-6474/17/371453-15$15.00/0.
A computationally efficient modelling of laminar separation bubbles
NASA Technical Reports Server (NTRS)
Dini, Paolo; Maughmer, Mark D.
1989-01-01
The goal is to accurately predict the characteristics of the laminar separation bubble and its effects on airfoil performance. Toward this end, a computational model of the separation bubble was developed and incorporated into the Eppler and Somers airfoil design and analysis program. Thus far, the focus of the research was limited to the development of a model which can accurately predict situations in which the interaction between the bubble and the inviscid velocity distribution is weak, the so-called short bubble. A summary of the research performed in the past nine months is presented. The bubble model in its present form is then described. Lastly, the performance of this model in predicting bubble characteristics is shown for a few cases.
Theory of low frequency noise transmission through turbines
NASA Technical Reports Server (NTRS)
Matta, R. K.; Mani, R.
1979-01-01
Improvements of the existing theory of low frequency noise transmission through turbines and development of a working prediction tool are described. The existing actuator-disk model and a new finite-chord model were utilized in an analytical study. The interactive effect of adjacent blade rows, higher order spinning modes, blade-passage shocks, and duct area variations were considered separately. The improved theory was validated using the data acquired in an earlier NASA program. Computer programs incorporating the improved theory were produced for transmission loss prediction purposes. The programs were exercised parametrically and charts constructed to define approximately the low frequency noise transfer through turbines. The loss through the exhaust nozzle and flow(s) was also considered.
Extravehicular mobility unit thermal simulator
NASA Technical Reports Server (NTRS)
Hixon, C. W.; Phillips, M. A.
1973-01-01
The analytical methods, thermal model, and user's instructions for the SIM bay extravehicular mobility unit (EMU) routine are presented. This digital computer program was developed for detailed thermal performance predictions of the crewman performing a command module extravehicular activity during transearth coast. It accounts for conductive, convective, and radiative heat transfer as well as fluid flow and associated flow control components. The program is a derivative of the Apollo lunar surface EMU digital simulator. It has the operational flexibility to accept card or magnetic tape for both the input data and program logic. Output can be tabular and/or plotted and the mission simulation can be stopped and restarted at the discretion of the user. The program was developed for the NASA-JSC Univac 1108 computer system and several of the capabilities represent utilization of unique features of that system. Analytical methods used in the computer routine are based on finite difference approximations to differential heat and mass balance equations which account for temperature or time dependent thermo-physical properties.
Research papers and publications (1981-1987): Workload research program
NASA Technical Reports Server (NTRS)
Hart, Sandra G. (Compiler)
1987-01-01
An annotated bibliography of the research reports written by participants in NASA's Workload Research Program since 1981 is presented, representing the results of theoretical and applied research conducted at Ames Research Center and at universities and industrial laboratories funded by the program. The major program elements included: 1) developing an understanding of the workload concept; 2) providing valid, reliable, and practical measures of workload; and 3) creating a computer model to predict workload. The goal is to provide workload-related design principles, measures, guidelines, and computational models. The research results are transferred to user groups by establishing close ties with manufacturers, civil and military operators of aerospace systems, and regulatory agencies; publishing scientific articles; participating in and sponsoring workshops and symposia; providing information, guidelines, and computer models; and contributing to the formulation of standards. In addition, the methods and theories developed have been applied to specific operational and design problems at the request of a number of industry and government agencies.
NASA Technical Reports Server (NTRS)
Mironenko, G.
1972-01-01
Programs for the analyses of the free or forced, undamped vibrations of one or two elastically-coupled lumped parameter teams are presented. Bearing nonlinearities, casing and rotor distributed mass and elasticity, rotor imbalance, forcing functions, gyroscopic moments, rotary inertia, and shear and flexural deformations are all included in the system dynamics analysis. All bearings have nonlinear load displacement characteristics, the solution is achieved by iteration. Rotor imbalances allowed by such considerations as pilot tolerances and runouts as well as bearing clearances (allowing concail or cylindrical whirl) determine the forcing function magnitudes. The computer programs first obtain a solution wherein the bearings are treated as linear springs of given spring rates. Then, based upon the computed bearing reactions, new spring rates are predicted and another solution of the modified system is made. The iteration is continued until the changes to bearing spring rates and bearing reactions become negligibly small.
NASA Technical Reports Server (NTRS)
Dunbar, D. N.; Tunnah, B. G.
1978-01-01
The FORTRAN computing program predicts the flow streams and material, energy, and economic balances of a typical petroleum refinery, with particular emphasis on production of aviation turbine fuel of varying end point and hydrogen content specifications. The program has provision for shale oil and coal oil in addition to petroleum crudes. A case study feature permits dependent cases to be run for parametric or optimization studies by input of only the variables which are changed from the base case. The report has sufficient detail for the information of most readers.
NASA Technical Reports Server (NTRS)
Goldhirsh, J.
1977-01-01
Disdrometer measurements and radar reflectivity measurements were injected into a computer program to estimate the path attenuation of the signal. Predicted attenuations when compared with the directly measured ones showed generally good correlation on a case by case basis and very good agreement statistically. The utility of using radar in conjunction with disdrometer measurements for predicting fade events and long term fade distributions associated with earth-satellite telecommunications is demonstrated.
Varying execution discipline to increase performance
DOE Office of Scientific and Technical Information (OSTI.GOV)
Campbell, P.L.; Maccabe, A.B.
1993-12-22
This research investigates the relationship between execution discipline and performance. The hypothesis has two parts: 1. Different execution disciplines exhibit different performance for different computations, and 2. These differences can be effectively predicted by heuristics. A machine model is developed that can vary its execution discipline. That is, the model can execute a given program using either the control-driven, data-driven or demand-driven execution discipline. This model is referred to as a ``variable-execution-discipline`` machine. The instruction set for the model is the Program Dependence Web (PDW). The first part of the hypothesis will be tested by simulating the execution of themore » machine model on a suite of computations, based on the Livermore Fortran Kernel (LFK) Test (a.k.a. the Livermore Loops), using all three execution disciplines. Heuristics are developed to predict relative performance. These heuristics predict (a) the execution time under each discipline for one iteration of each loop and (b) the number of iterations taken by that loop; then the heuristics use those predictions to develop a prediction for the execution of the entire loop. Similar calculations are performed for branch statements. The second part of the hypothesis will be tested by comparing the results of the simulated execution with the predictions produced by the heuristics. If the hypothesis is supported, then the door is open for the development of machines that can vary execution discipline to increase performance.« less
The EMCC / DARPA Massively Parallel Electromagnetic Scattering Project
NASA Technical Reports Server (NTRS)
Woo, Alex C.; Hill, Kueichien C.
1996-01-01
The Electromagnetic Code Consortium (EMCC) was sponsored by the Advanced Research Program Agency (ARPA) to demonstrate the effectiveness of massively parallel computing in large scale radar signature predictions. The EMCC/ARPA project consisted of three parts.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Ecale Zhou, Carol L.
2016-07-05
Compare Gene Calls (CGC) is a Python code used for combining and comparing gene calls from any number of gene callers. A gene caller is a computer program that predicts the extends of open reading frames within genomes of biological organisms.
THE TOXCAST PROGRAM FOR PRIORITIZING TOXICITY TESTING OF ENVIRONMENTAL CHEMICALS
The United States Environmental Protection Agency (EPA) is developing methods for utilizing computational chemistry, high-throughput screening (HTS) and various toxicogenomic technologies to predict potential for toxicity and prioritize limited testing resources towards chemicals...
Developments in REDES: The rocket engine design expert system
NASA Technical Reports Server (NTRS)
Davidian, Kenneth O.
1990-01-01
The Rocket Engine Design Expert System (REDES) is being developed at the NASA-Lewis to collect, automate, and perpetuate the existing expertise of performing a comprehensive rocket engine analysis and design. Currently, REDES uses the rigorous JANNAF methodology to analyze the performance of the thrust chamber and perform computational studies of liquid rocket engine problems. The following computer codes were included in REDES: a gas properties program named GASP, a nozzle design program named RAO, a regenerative cooling channel performance evaluation code named RTE, and the JANNAF standard liquid rocket engine performance prediction code TDK (including performance evaluation modules ODE, ODK, TDE, TDK, and BLM). Computational analyses are being conducted by REDES to provide solutions to liquid rocket engine thrust chamber problems. REDES is built in the Knowledge Engineering Environment (KEE) expert system shell and runs on a Sun 4/110 computer.
Developments in REDES: The Rocket Engine Design Expert System
NASA Technical Reports Server (NTRS)
Davidian, Kenneth O.
1990-01-01
The Rocket Engine Design Expert System (REDES) was developed at NASA-Lewis to collect, automate, and perpetuate the existing expertise of performing a comprehensive rocket engine analysis and design. Currently, REDES uses the rigorous JANNAF methodology to analyze the performance of the thrust chamber and perform computational studies of liquid rocket engine problems. The following computer codes were included in REDES: a gas properties program named GASP; a nozzle design program named RAO; a regenerative cooling channel performance evaluation code named RTE; and the JANNAF standard liquid rocket engine performance prediction code TDK (including performance evaluation modules ODE, ODK, TDE, TDK, and BLM). Computational analyses are being conducted by REDES to provide solutions to liquid rocket engine thrust chamber problems. REDES was built in the Knowledge Engineering Environment (KEE) expert system shell and runs on a Sun 4/110 computer.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Spycher, Nicolas; Peiffer, Loic; Finsterle, Stefan
GeoT implements the multicomponent geothermometry method developed by Reed and Spycher (1984, Geochim. Cosmichim. Acta 46 513–528) into a stand-alone computer program, to ease the application of this method and to improve the prediction of geothermal reservoir temperatures using full and integrated chemical analyses of geothermal fluids. Reservoir temperatures are estimated from statistical analyses of mineral saturation indices computed as a function of temperature. The reconstruction of the deep geothermal fluid compositions, and geothermometry computations, are all implemented into the same computer program, allowing unknown or poorly constrained input parameters to be estimated by numerical optimization using existing parameter estimationmore » software, such as iTOUGH2, PEST, or UCODE. This integrated geothermometry approach presents advantages over classical geothermometers for fluids that have not fully equilibrated with reservoir minerals and/or that have been subject to processes such as dilution and gas loss.« less
1977-07-01
on an IBM 370/165 computer at The University of Kentucky using the Fortran IV, G level compiler and should be easily implemented on other computers...order as the columns of T. 3.5.3 Subroutines NROOT and EIGEN Subroutines NROOT and EIGEN are a set of subroutines from the IBM Scientific Subroutine...November 1975). [10] System/360 Scientific Subroutine Package, Version III, Fifth Edition (August 1970), IBM Corporation, Technical Publications
NASA Computational Fluid Dynamics Conference. Volume 1: Sessions 1-6
NASA Technical Reports Server (NTRS)
1989-01-01
Presentations given at the NASA Computational Fluid Dynamics (CFD) Conference held at the NASA Ames Research Center, Moffett Field, California, March 7-9, 1989 are given. Topics covered include research facility overviews of CFD research and applications, validation programs, direct simulation of compressible turbulence, turbulence modeling, advances in Runge-Kutta schemes for solving 3-D Navier-Stokes equations, grid generation and invicid flow computation around aircraft geometries, numerical simulation of rotorcraft, and viscous drag prediction for rotor blades.
Linear Scaling Density Functional Calculations with Gaussian Orbitals
NASA Technical Reports Server (NTRS)
Scuseria, Gustavo E.
1999-01-01
Recent advances in linear scaling algorithms that circumvent the computational bottlenecks of large-scale electronic structure simulations make it possible to carry out density functional calculations with Gaussian orbitals on molecules containing more than 1000 atoms and 15000 basis functions using current workstations and personal computers. This paper discusses the recent theoretical developments that have led to these advances and demonstrates in a series of benchmark calculations the present capabilities of state-of-the-art computational quantum chemistry programs for the prediction of molecular structure and properties.
Horizon sensor errors calculated by computer models compared with errors measured in orbit
NASA Technical Reports Server (NTRS)
Ward, K. A.; Hogan, R.; Andary, J.
1982-01-01
Using a computer program to model the earth's horizon and to duplicate the signal processing procedure employed by the ESA (Earth Sensor Assembly), errors due to radiance variation have been computed for a particular time of the year. Errors actually occurring in flight at the same time of year are inferred from integrated rate gyro data for a satellite of the TIROS series of NASA weather satellites (NOAA-A). The predicted performance is compared with actual flight history.
Thermal Ablation Modeling for Silicate Materials
NASA Technical Reports Server (NTRS)
Chen, Yih-Kanq
2016-01-01
A thermal ablation model for silicates is proposed. The model includes the mass losses through the balance between evaporation and condensation, and through the moving molten layer driven by surface shear force and pressure gradient. This model can be applied in ablation simulations of the meteoroid or glassy Thermal Protection Systems for spacecraft. Time-dependent axi-symmetric computations are performed by coupling the fluid dynamics code, Data-Parallel Line Relaxation program, with the material response code, Two-dimensional Implicit Thermal Ablation simulation program, to predict the mass lost rates and shape change. For model validation, the surface recession of fused amorphous quartz rod is computed, and the recession predictions reasonably agree with available data. The present parametric studies for two groups of meteoroid earth entry conditions indicate that the mass loss through moving molten layer is negligibly small for heat-flux conditions at around 1 MW/cm(exp. 2).
Numerical Modeling of Flow Distribution in Micro-Fluidics Systems
NASA Technical Reports Server (NTRS)
Majumdar, Alok; Cole, Helen; Chen, C. P.
2005-01-01
This paper describes an application of a general purpose computer program, GFSSP (Generalized Fluid System Simulation Program) for calculating flow distribution in a network of micro-channels. GFSSP employs a finite volume formulation of mass and momentum conservation equations in a network consisting of nodes and branches. Mass conservation equation is solved for pressures at the nodes while the momentum conservation equation is solved at the branches to calculate flowrate. The system of equations describing the fluid network is solved by a numerical method that is a combination of the Newton-Raphson and successive substitution methods. The numerical results have been compared with test data and detailed CFD (computational Fluid Dynamics) calculations. The agreement between test data and predictions is satisfactory. The discrepancies between the predictions and test data can be attributed to the frictional correlation which does not include the effect of surface tension or electro-kinetic effect.
Design and Operating Characteristics of High-Speed, Small-Bore Cylindrical-Roller Bearings
NASA Technical Reports Server (NTRS)
Pinel, Stanley, I.; Signer, Hans R.; Zaretsky, Erwin V.
2000-01-01
The computer program SHABERTH was used to analyze 35-mm-bore cylindrical roller bearings designed and manufactured for high-speed turbomachinery applications. Parametric tests of the bearings were conducted on a high-speed, high-temperature bearing tester and the results were compared with the computer predictions. Bearings with a channeled inner ring were lubricated through the inner ring, while bearings with a channeled outer ring were lubricated with oil jets. Tests were run with and without outer-ring cooling. The predicted bearing life decreased with increasing speed because of increased contact stresses caused by centrifugal load. Lower temperatures, less roller skidding, and lower power losses were obtained with channeled inner rings. Power losses calculated by the SHABERTH computer program correlated reasonably well with the test results. The Parker formula for XCAV (used in SHABERTH as a measure of oil volume in the bearing cavity) needed to be adjusted to reflect the prevailing operating conditions. The XCAV formula will need to be further refined to reflect roller bearing lubrication, ring design, cage design, and location of the cage-controlling land.
Parallelized direct execution simulation of message-passing parallel programs
NASA Technical Reports Server (NTRS)
Dickens, Phillip M.; Heidelberger, Philip; Nicol, David M.
1994-01-01
As massively parallel computers proliferate, there is growing interest in findings ways by which performance of massively parallel codes can be efficiently predicted. This problem arises in diverse contexts such as parallelizing computers, parallel performance monitoring, and parallel algorithm development. In this paper we describe one solution where one directly executes the application code, but uses a discrete-event simulator to model details of the presumed parallel machine such as operating system and communication network behavior. Because this approach is computationally expensive, we are interested in its own parallelization specifically the parallelization of the discrete-event simulator. We describe methods suitable for parallelized direct execution simulation of message-passing parallel programs, and report on the performance of such a system, Large Application Parallel Simulation Environment (LAPSE), we have built on the Intel Paragon. On all codes measured to date, LAPSE predicts performance well typically within 10 percent relative error. Depending on the nature of the application code, we have observed low slowdowns (relative to natively executing code) and high relative speedups using up to 64 processors.
NASA Astrophysics Data System (ADS)
Hartmann Siantar, Christine L.; Moses, Edward I.
1998-11-01
When using radiation to treat cancer, doctors rely on physics and computer technology to predict where the radiation dose will be deposited in the patient. The accuracy of computerized treatment planning plays a critical role in the ultimate success or failure of the radiation treatment. Inaccurate dose calculations can result in either insufficient radiation for cure, or excessive radiation to nearby healthy tissue, which can reduce the patient's quality of life. This paper describes how advanced physics, computer, and engineering techniques originally developed for nuclear weapons and high-energy physics research are being used to predict radiation dose in cancer patients. Results for radiation therapy planning, achieved in the Lawrence Livermore National Laboratory (LLNL) 0143-0807/19/6/005/img2 program show that these tools can give doctors new insights into their patients' treatments by providing substantially more accurate dose distributions than have been available in the past. It is believed that greater accuracy in radiation therapy treatment planning will save lives by improving doctors' ability to target radiation to the tumour and reduce suffering by reducing the incidence of radiation-induced complications.
Strong Shock Propagating Over A Random Bed of Spherical Particles
NASA Astrophysics Data System (ADS)
Mehta, Yash; Salari, Kambiz; Jackson, Thomas L.; Balachandar, S.; Thakur, Siddharth
2017-11-01
The study of shock interaction with particles has been largely motivated because of its wide-ranging applications. The complex interaction between the compressible flow features, such as shock wave and expansion fan, and the dispersed phase makes this multi-phase flow very difficult to predict and control. In this talk we will be presenting results on fully resolved inviscid simulations of shock interaction with random bed of particles. One of the fascinating observations from these simulations are the flow field fluctuations due to the presence of randomly distributed particles. Rigorous averaging (Favre averaging) of the governing equations results in Reynolds stress like term, which can be classified as pseudo turbulence in this case. We have computed this ``Reynolds stress'' term along with individual fluctuations and the turbulent kinetic energy. Average pressure was also computed to characterize the strength of the transmitted and the reflected waves. This work was supported by the U.S. Department of Energy, National Nuclear Security Administration, Advanced Simulation and Computing Program, as a Cooperative Agreement under the Predictive Science Academic Alliance Program.
Noise produced by turbulent flow into a rotor: Users manual for noise calculation
NASA Technical Reports Server (NTRS)
Amiet, R. K.; Egolf, C. G.; Simonich, J. C.
1989-01-01
A users manual for a computer program for the calculation of noise produced by turbulent flow into a helicopter rotor is presented. These inputs to the program are obtained from the atmospheric turbulence model and mean flow distortion calculation, described in another volume of this set of reports. Descriptions of the various program modules and subroutines, their function, programming structure, and the required input and output variables are included. This routine is incorporated as one module of NASA's ROTONET helicopter noise prediction program.
NASA Technical Reports Server (NTRS)
Omori, S.
1973-01-01
As described in Vol. 1, the eddy viscosity is calculated through the turbulent kinetic energy, in order to include the history of the flow and the effect of chemical reaction on boundary layer characteristics. Calculations can be performed for two different cooling concepts; that is, transpiration and regeneratively cooled wall cases. For the regenerative cooling option, coolant and gas side wall temperature and coolant bulk temperature in a rocket engine can be computed along the nozzle axis. Thus, this computer program is useful in designing coolant flow rate and cooling tube geometry, including the tube wall thickness as well as in predicting the effects of boundary layers along the gas side wall on thrust performances.
ERIC Educational Resources Information Center
Sween, Joyce; Campbell, Donald T.
Computational formulae for the following three tests of significance, useful in the interrupted time series design, are given: (1) a "t" test (Mood, 1950) for the significance of the first post-change observation from a value predicted by a linear fit of the pre-change observations; (2) an "F" test (Walker and Lev, 1953) of the…
S.J. Chang; Rodney L. Busby; P.R. Pasala; Daniel J. Leduc
2005-01-01
A Visual Basic computer model that can be used to estimate the harvestvalue of loblolly pine plantations in the west gulf region is presented. Themodel uses a dynamic programming algorithm to convert stand tablespredicted by COMPUTE_P-LOB into a listing of seven products thatmaximizes the harvested value of the stand.
S.J. Chang; Rodney L. Busby; P.R. Pasala; Jeffrey C. Goelz
2005-01-01
A Visual Basic computer model that can be used to estimate the harvestvalue of slash pine plantations in the west gulf region is presented. Themodel uses a dynamic programming algorithm to convert stand tablespredicted by COMPUTE_P-SLASH into a listing of seven products thatmaximizes the harvested value of the stand.
Use of the negative binomial-truncated Poisson distribution in thunderstorm prediction
NASA Technical Reports Server (NTRS)
Cohen, A. C.
1971-01-01
A probability model is presented for the distribution of thunderstorms over a small area given that thunderstorm events (1 or more thunderstorms) are occurring over a larger area. The model incorporates the negative binomial and truncated Poisson distributions. Probability tables for Cape Kennedy for spring, summer, and fall months and seasons are presented. The computer program used to compute these probabilities is appended.
Computational tools for fitting the Hill equation to dose-response curves.
Gadagkar, Sudhindra R; Call, Gerald B
2015-01-01
Many biological response curves commonly assume a sigmoidal shape that can be approximated well by means of the 4-parameter nonlinear logistic equation, also called the Hill equation. However, estimation of the Hill equation parameters requires access to commercial software or the ability to write computer code. Here we present two user-friendly and freely available computer programs to fit the Hill equation - a Solver-based Microsoft Excel template and a stand-alone GUI-based "point and click" program, called HEPB. Both computer programs use the iterative method to estimate two of the Hill equation parameters (EC50 and the Hill slope), while constraining the values of the other two parameters (the minimum and maximum asymptotes of the response variable) to fit the Hill equation to the data. In addition, HEPB draws the prediction band at a user-defined confidence level, and determines the EC50 value for each of the limits of this band to give boundary values that help objectively delineate sensitive, normal and resistant responses to the drug being tested. Both programs were tested by analyzing twelve datasets that varied widely in data values, sample size and slope, and were found to yield estimates of the Hill equation parameters that were essentially identical to those provided by commercial software such as GraphPad Prism and nls, the statistical package in the programming language R. The Excel template provides a means to estimate the parameters of the Hill equation and plot the regression line in a familiar Microsoft Office environment. HEPB, in addition to providing the above results, also computes the prediction band for the data at a user-defined level of confidence, and determines objective cut-off values to distinguish among response types (sensitive, normal and resistant). Both programs are found to yield estimated values that are essentially the same as those from standard software such as GraphPad Prism and the R-based nls. Furthermore, HEPB also has the option to simulate 500 response values based on the range of values of the dose variable in the original data and the fit of the Hill equation to that data. Copyright © 2014. Published by Elsevier Inc.
NASA Technical Reports Server (NTRS)
Dunbar, D. N.; Tunnah, B. G.
1979-01-01
Program predicts production volumes of petroleum refinery products, with particular emphasis on aircraft-turbine fuel blends and their key properties. It calculates capital and operating costs for refinery and its margin of profitability. Program also includes provisions for processing of synthetic crude oils from oil shale and coal liquefaction processes and contains highly-detailed blending computations for alternative jet-fuel blends of varying endpoint specifications.
Patricia K. Lebow; Henry Spelter; Peter J. Ince
2003-01-01
This report provides documentation and user information for FPL-PELPS, a personal computer price endogenous linear programming system for economic modeling. Originally developed to model the North American pulp and paper industry, FPL-PELPS follows its predecessors in allowing the modeling of any appropriate sector to predict consumption, production and capacity by...
Short-Term Forecasting of Radiation Belt and Ring Current
NASA Technical Reports Server (NTRS)
Fok, Mei-Ching
2007-01-01
A computer program implements a mathematical model of the radiation-belt and ring-current plasmas resulting from interactions between the solar wind and the Earth s magnetic field, for the purpose of predicting fluxes of energetic electrons (10 keV to 5 MeV) and protons (10 keV to 1 MeV), which are hazardous to humans and spacecraft. Given solar-wind and interplanetary-magnetic-field data as inputs, the program solves the convection-diffusion equations of plasma distribution functions in the range of 2 to 10 Earth radii. Phenomena represented in the model include particle drifts resulting from the gradient and curvature of the magnetic field; electric fields associated with the rotation of the Earth, convection, and temporal variation of the magnetic field; and losses along particle-drift paths. The model can readily accommodate new magnetic- and electric-field submodels and new information regarding physical processes that drive the radiation-belt and ring-current plasmas. Despite the complexity of the model, the program can be run in real time on ordinary computers. At present, the program can calculate present electron and proton fluxes; after further development, it should be able to predict the fluxes 24 hours in advance
NASA Technical Reports Server (NTRS)
Rule, W. K.; Hayashida, K. B.
1992-01-01
The development of a computer program to predict the degradation of the insulating capabilities of the multilayer insulation (MLI) blanket of Space Station Freedom due to a hypervelocity impact with a space debris particle is described. A finite difference scheme is used for the calculations. The computer program was written in Microsoft BASIC. Also described is a test program that was undertaken to validate the numerical model. Twelve MLI specimens were impacted at hypervelocities with simulated debris particles using a light gas gun at Marshall Space Flight Center. The impact-damaged MLI specimens were then tested for insulating capability in the space environment of the Sunspot thermal vacuum chamber at MSFC. Two undamaged MLI specimens were also tested for comparison with the test results of the damaged specimens. The numerical model was found to adequately predict behavior of the MLI specimens in the Sunspot chamber. A parameter, called diameter ratio, was developed to relate the nominal MLI impact damage to the apparent (for thermal analysis purposes) impact damage based on the hypervelocity impact conditions of a specimen.
NASA Technical Reports Server (NTRS)
Aggarwal, Arun K.
1993-01-01
Spherical roller bearings have typically been used in applications with speeds limited to about 5000 rpm and loads limited for operation at less than about 0.25 million DN. However, spherical roller bearings are now being designed for high load and high speed applications including aerospace applications. A computer program, SASHBEAN, was developed to provide an analytical tool to design, analyze, and predict the performance of high speed, single row, angular contact (including zero contact angle), spherical roller bearings. The material presented is the mathematical formulation and analytical methods used to develop computer program SASHBEAN. For a given set of operating conditions, the program calculates the bearings ring deflections (axial and radial), roller deflections, contact areas stresses, depth and magnitude of maximum shear stresses, axial thrust, rolling element and cage rotational speeds, lubrication parameters, fatigue lives, and rates of heat generation. Centrifugal forces and gyroscopic moments are fully considered. The program is also capable of performing steady-state and time-transient thermal analyses of the bearing system.
[ProteoСat: a tool for planning of proteomic experiments].
Skvortsov, V S; Alekseychuk, N N; Khudyakov, D V; Mikurova, A V; Rybina, A V; Novikova, S E; Tikhonova, O V
2015-01-01
ProteoCat is a computer program has been designed to help researchers in the planning of large-scale proteomic experiments. The central part of this program is the subprogram of hydrolysis simulation that supports 4 proteases (trypsin, lysine C, endoproteinases AspN and GluC). For the peptides obtained after virtual hydrolysis or loaded from data file a number of properties important in mass-spectrometric experiments can be calculated or predicted. The data can be analyzed or filtered to reduce a set of peptides. The program is using new and improved modification of our methods developed to predict pI and probability of peptide detection; pI can also be predicted for a number of popular pKa's scales, proposed by other investigators. The algorithm for prediction of peptide retention time was realized similar to the algorithm used in the program SSRCalc. ProteoCat can estimate the coverage of amino acid sequences of proteins under defined limitation on peptides detection, as well as the possibility of assembly of peptide fragments with user-defined size of "sticky" ends. The program has a graphical user interface, written on JAVA and available at http://www.ibmc.msk.ru/LPCIT/ProteoCat.
Analysis of a Multiprocessor Guidance Computer. Ph.D. Thesis
NASA Technical Reports Server (NTRS)
Maltach, E. G.
1969-01-01
The design of the next generation of spaceborne digital computers is described. It analyzes a possible multiprocessor computer configuration. For the analysis, a set of representative space computing tasks was abstracted from the Lunar Module Guidance Computer programs as executed during the lunar landing, from the Apollo program. This computer performs at this time about 24 concurrent functions, with iteration rates from 10 times per second to once every two seconds. These jobs were tabulated in a machine-independent form, and statistics of the overall job set were obtained. It was concluded, based on a comparison of simulation and Markov results, that the Markov process analysis is accurate in predicting overall trends and in configuration comparisons, but does not provide useful detailed information in specific situations. Using both types of analysis, it was determined that the job scheduling function is a critical one for efficiency of the multiprocessor. It is recommended that research into the area of automatic job scheduling be performed.
Khozani, Zohreh Sheikh; Bonakdari, Hossein; Zaji, Amir Hossein
2016-01-01
Two new soft computing models, namely genetic programming (GP) and genetic artificial algorithm (GAA) neural network (a combination of modified genetic algorithm and artificial neural network methods) were developed in order to predict the percentage of shear force in a rectangular channel with non-homogeneous roughness. The ability of these methods to estimate the percentage of shear force was investigated. Moreover, the independent parameters' effectiveness in predicting the percentage of shear force was determined using sensitivity analysis. According to the results, the GP model demonstrated superior performance to the GAA model. A comparison was also made between the GP program determined as the best model and five equations obtained in prior research. The GP model with the lowest error values (root mean square error ((RMSE) of 0.0515) had the best function compared with the other equations presented for rough and smooth channels as well as smooth ducts. The equation proposed for rectangular channels with rough boundaries (RMSE of 0.0642) outperformed the prior equations for smooth boundaries.
NASA Technical Reports Server (NTRS)
Moyer, C. B.; Green, K. A.
1972-01-01
Comparisons of ablation calculations with the charring ablation computer code and ablation test data are presented over a wide range of environmental conditions in air for three materials: low-density nylon phenolic, Avcoat 5026-39HC/G, and a filled silicon elastomer. Heat fluxes considered range from over 500 Btu/sq ft-sec to less than 50 Btu/sq ft-sec. Pressures range from 0.5 atm to .004 atm. Enthalpies range from about 2000 Btu/lb to 18000 Btu/lb. Predictions of recession, pyrolysis penetration, and thermocouple responses are considered. Recession predictions for nylon phenolic are good as steady state is approached, but strongly transient cases are underpredicted. Pyrolysis penetrations and thermocouple responses are very well predicted. Recession amounts for Avcoat and silicone elastomer are less well predicted, although high heat flux cases near steady state are fairly satisfactory. Pyrolysis penetrations and thermocouple responses are very well predicted.
Hydrometeorological model for streamflow prediction
Tangborn, Wendell V.
1979-01-01
The hydrometeorological model described in this manual was developed to predict seasonal streamflow from water in storage in a basin using streamflow and precipitation data. The model, as described, applies specifically to the Skokomish, Nisqually, and Cowlitz Rivers, in Washington State, and more generally to streams in other regions that derive seasonal runoff from melting snow. Thus the techniques demonstrated for these three drainage basins can be used as a guide for applying this method to other streams. Input to the computer program consists of daily averages of gaged runoff of these streams, and daily values of precipitation collected at Longmire, Kid Valley, and Cushman Dam. Predictions are based on estimates of the absolute storage of water, predominately as snow: storage is approximately equal to basin precipitation less observed runoff. A pre-forecast test season is used to revise the storage estimate and improve the prediction accuracy. To obtain maximum prediction accuracy for operational applications with this model , a systematic evaluation of several hydrologic and meteorologic variables is first necessary. Six input options to the computer program that control prediction accuracy are developed and demonstrated. Predictions of streamflow can be made at any time and for any length of season, although accuracy is usually poor for early-season predictions (before December 1) or for short seasons (less than 15 days). The coefficient of prediction (CP), the chief measure of accuracy used in this manual, approaches zero during the late autumn and early winter seasons and reaches a maximum of about 0.85 during the spring snowmelt season. (Kosco-USGS)
RFI Math Model programs for predicting intermodulation interference
NASA Technical Reports Server (NTRS)
Stafford, J. M.
1974-01-01
Receivers operating on a space vehicle or an aircraft having many on-board transmitters are subject to intermodulation interference from mixing in the transmitting antenna systems, the external environment, or the receiver front-ends. This paper presents the techniques utilized in RFI Math Model computer programs that were developed to aid in the prevention of interference by predicting problem areas prior to occurrence. Frequencies and amplitudes of possible intermodulation products generated in the external environment are calculated and compared to receiver sensitivities. Intermodulation products generated in receivers are evaluated to determine the adequacy of preselector ejection.
NASA Technical Reports Server (NTRS)
Horta, Lucas G.; Reaves, Mercedes C.
2008-01-01
As NASA moves towards developing technologies needed to implement its new Exploration program, studies conducted for Apollo in the 1960's to understand the rollover stability of capsules landing are being revisited. Although rigid body kinematics analyses of the roll-over behavior of capsules on impact provided critical insight to the Apollo problem, extensive ground test programs were also used. For the new Orion spacecraft being developed to implement today's Exploration program, new air-bag designs have improved sufficiently for NASA to consider their use to mitigate landing loads to ensure crew safety and to enable re-usability of the capsule. Simple kinematics models provide only limited understanding of the behavior of these air bag systems, and more sophisticated tools must be used. In particular, NASA and its contractors are using the LS-Dyna nonlinear simulation code for impact response predictions of the full Orion vehicle with air bags by leveraging the extensive air bag prediction work previously done by the automotive industry. However, even in today's computational environment, these analyses are still high-dimensional, time consuming, and computationally intensive. To alleviate the computational burden, this paper presents an approach that uses deterministic sampling techniques and an adaptive response surface method to not only use existing LS-Dyna solutions but also to interpolate from LS-Dyna solutions to predict the stability boundaries for a capsule on airbags. Results for the stability boundary in terms of impact velocities, capsule attitude, impact plane orientation, and impact surface friction are discussed.
User's manual for University of Arizona APART program (Analysis Program - Arizona Radiation Trace)
NASA Technical Reports Server (NTRS)
Breault, R. P.
1975-01-01
A description and operating instructions for the Analysis Program Arizona Radiation Trace (APART) are given. This is a computer program that is able to efficiently and accurately predict the off-axis rejection characteristics of unwanted stray radiation for complex rotationally symmetric optical systems. The program first determines the critical objects or areas that scatter radiation to the image plane either directly or through imaging elements: this provides the opportunity to modify, if necessary, the design so that the number of critical areas seen by the image plane is reduced or the radiation to these critical areas is minimized. Next, the power distribution reaching the image plane and a sectional power map of all internal surfaces are computed. Angular information is also provided that relates the angle by which the radiation came into a surface to the angle by which the radiation is scattered out of the surface.
A nonproprietary, nonsecret program for calculating Stirling cryocoolers
NASA Technical Reports Server (NTRS)
Martini, W. R.
1985-01-01
A design program for an integrated Stirling cycle cryocooler was written on an IBM-PC computer. The program is easy to use and shows the trends and itemizes the losses. The calculated results were compared with some measured performance values. The program predicts somewhat optimistic performance and needs to be calibrated more with experimental measurements. Adding a multiplier to the friction factor can bring the calculated rsults in line with the limited test results so far available. The program is offered as a good framework on which to build a truly useful design program for all types of cryocoolers.
SH2 Ligand Prediction-Guidance for In-Silico Screening.
Li, Shawn S C; Li, Lei
2017-01-01
Systematic identification of binding partners for SH2 domains is important for understanding the biological function of the corresponding SH2 domain-containing proteins. Here, we describe two different web-accessible computer programs, SMALI and DomPep, for predicting binding ligands for SH2 domains. The former was developed using a Scoring Matrix method and the latter based on the Support Vector Machine model.
A computer program for cyclic plasticity and structural fatigue analysis
NASA Technical Reports Server (NTRS)
Kalev, I.
1980-01-01
A computerized tool for the analysis of time independent cyclic plasticity structural response, life to crack initiation prediction, and crack growth rate prediction for metallic materials is described. Three analytical items are combined: the finite element method with its associated numerical techniques for idealization of the structural component, cyclic plasticity models for idealization of the material behavior, and damage accumulation criteria for the fatigue failure.
ERIC Educational Resources Information Center
Milbank, N. O.
The paper argues that existing computer programs for thermal predictions do not produce suitable information for architects, particularly at the early stages of design. It reviews the important building features that determine the thermal environment and the need for heating and cooling plant. Graphical design aids are proposed, with examples to…
DOE Office of Scientific and Technical Information (OSTI.GOV)
Palermo, M.R.; Schroeder, P.R.
This technical note describes a technique for comparison of the predicted quality of effluent discharged from confined dredged material disposal areas with applicable water quality standards. This note also serves as documentation of a computer program called EFQUAL written for that purpose as part of the Automated Dredging and Disposal Alternatives Management System (ADDAMS).
FHWA traffic noise model, version 1.0 : user's guide
DOT National Transportation Integrated Search
1998-01-01
This User's Guide is for the Federal Highway Administration's Traffic Noise Model (FHWA TNM), Version 1.0 -- the FHWAs computer program for highway traffic noise prediction and analysis. Two companion reports, a Technical Manual and a data repor...
FHWA Traffic Noise Model, version 1.0 technical manual
DOT National Transportation Integrated Search
1998-02-01
This Technical Manual is for the Federal Highway Administrations Traffic Noise Model (FHWA TNM), Version 1.0 -- the FHWAs computer program for highway traffic noise prediction and analysis. Two companion reports, a Users Guide and a data r...
Towards pattern generation and chaotic series prediction with photonic reservoir computers
NASA Astrophysics Data System (ADS)
Antonik, Piotr; Hermans, Michiel; Duport, François; Haelterman, Marc; Massar, Serge
2016-03-01
Reservoir Computing is a bio-inspired computing paradigm for processing time dependent signals that is particularly well suited for analog implementations. Our team has demonstrated several photonic reservoir computers with performance comparable to digital algorithms on a series of benchmark tasks such as channel equalisation and speech recognition. Recently, we showed that our opto-electronic reservoir computer could be trained online with a simple gradient descent algorithm programmed on an FPGA chip. This setup makes it in principle possible to feed the output signal back into the reservoir, and thus highly enrich the dynamics of the system. This will allow to tackle complex prediction tasks in hardware, such as pattern generation and chaotic and financial series prediction, which have so far only been studied in digital implementations. Here we report simulation results of our opto-electronic setup with an FPGA chip and output feedback applied to pattern generation and Mackey-Glass chaotic series prediction. The simulations take into account the major aspects of our experimental setup. We find that pattern generation can be easily implemented on the current setup with very good results. The Mackey-Glass series prediction task is more complex and requires a large reservoir and more elaborate training algorithm. With these adjustments promising result are obtained, and we now know what improvements are needed to match previously reported numerical results. These simulation results will serve as basis of comparison for experiments we will carry out in the coming months.
NASA Technical Reports Server (NTRS)
Farassat, F.; Succi, G. P.
1980-01-01
A review of propeller noise prediction technology is presented which highlights the developments in the field from the successful attempt of Gutin to the current sophisticated techniques. Two methods for the predictions of the discrete frequency noise from conventional and advanced propellers in forward flight are described. These methods developed at MIT and NASA Langley Research Center are based on different time domain formulations. Brief description of the computer algorithms based on these formulations are given. The output of these two programs, which is the acoustic pressure signature, is Fourier analyzed to get the acoustic pressure spectrum. The main difference between the programs as they are coded now is that the Langley program can handle propellers with supersonic tip speed while the MIT program is for subsonic tip speed propellers. Comparisons of the calculated and measured acoustic data for a conventional and an advanced propeller show good agreement in general.
Critical joints in large composite aircraft structure
NASA Technical Reports Server (NTRS)
Nelson, W. D.; Bunin, B. L.; Hart-Smith, L. J.
1983-01-01
A program was conducted at Douglas Aircraft Company to develop the technology for critical structural joints of composite wing structure that meets design requirements for a 1990 commercial transport aircraft. The prime objective of the program was to demonstrate the ability to reliably predict the strength of large bolted composite joints. Ancillary testing of 180 specimens generated data on strength and load-deflection characteristics which provided input to the joint analysis. Load-sharing between fasteners in multirow bolted joints was computed by the nonlinear analysis program A4EJ. This program was used to predict strengths of 20 additional large subcomponents representing strips from a wing root chordwise splice. In most cases, the predictions were accurate to within a few percent of the test results. In some cases, the observed mode of failure was different than anticipated. The highlight of the subcomponent testing was the consistent ability to achieve gross-section failure strains close to 0.005. That represents a considerable improvement over the state of the art.
A numerical simulation of the dispersal of aerial sprays
NASA Technical Reports Server (NTRS)
Bragg, M. B.
1981-01-01
A computer program was developed to predict the trajectory, ground deposition, and drift of liquid sprays injected into the wake of an agricultural aircraft in ground effect. The program uses a horseshoe vortex wake model and includes the effects of liquid droplet evaporation, crosswind, the propeller slipstream, ground effect, and tunnel walls on small scale models. This user's guide includes several case examples demonstrating user options. A complete listing of the FORTRAN program is provided.
Elastic-plastic analysis of a propagating crack under cyclic loading
NASA Technical Reports Server (NTRS)
Newman, J. C., Jr.; Armen, H., Jr.
1974-01-01
Development and application of a two-dimensional finite-element analysis to predict crack-closure and crack-opening stresses during specified histories of cyclic loading. An existing finite-element computer program which accounts for elastic-plastic material behavior under cyclic loading was modified to account for changing boundary conditions - crack growth and intermittent contact of crack surfaces. This program was subsequently used to study the crack-closure behavior under constant-amplitude and simple block-program loading.
Sanders, Mechelle; Fiscella, Kevin; Veazie, Peter; Dolan, James G; Jerant, Anthony
2016-08-01
The main aim is to examine whether patients' viewing time on information about colorectal cancer (CRC) screening before a primary care physician (PCP) visit is associated with discussion of screening options during the visit. We analyzed data from a multi-center randomized controlled trial of a tailored interactive multimedia computer program (IMCP) to activate patients to undergo CRC screening, deployed in primary care offices immediately before a visit. We employed usage time information stored in the IMCP to examine the association of patient time spent using the program with patient-reported discussion of screening during the visit, adjusting for previous CRC screening recommendation and reading speed.On average, patients spent 33 minutes on the program. In adjusted analyses, 30 minutes spent using the program was associated with a 41% increase in the odds of the patient having a discussion with their PCP (1.04, 1.59, 95% CI). In a separate analysis of the tailoring modules; the modules encouraging adherence to the tailored screening recommendation and discussion with the patient's PCP yielded significant results. Other predictors of screening discussion included better self-reported physical health and increased patient activation. Time spent on the program predicted greater patient-physician discussion of screening during a linked visit.Usage time information gathered automatically by IMCPs offers promise for objectively assessing patient engagement around a topic and predicting likelihood of discussion between patients and their clinician. © The Author 2016. Published by Oxford University Press. All rights reserved. For permissions, please email: journals.permissions@oup.com.
A Distributed Laboratory for Event-Driven Coastal Prediction and Hazard Planning
NASA Astrophysics Data System (ADS)
Bogden, P.; Allen, G.; MacLaren, J.; Creager, G. J.; Flournoy, L.; Sheng, Y. P.; Graber, H.; Graves, S.; Conover, H.; Luettich, R.; Perrie, W.; Ramakrishnan, L.; Reed, D. A.; Wang, H. V.
2006-12-01
The 2005 Atlantic hurricane season was the most active in recorded history. Collectively, 2005 hurricanes caused more than 2,280 deaths and record damages of over 100 billion dollars. Of the storms that made landfall, Dennis, Emily, Katrina, Rita, and Wilma caused most of the destruction. Accurate predictions of storm-driven surge, wave height, and inundation can save lives and help keep recovery costs down, provided the information gets to emergency response managers in time. The information must be available well in advance of landfall so that responders can weigh the costs of unnecessary evacuation against the costs of inadequate preparation. The SURA Coastal Ocean Observing and Prediction (SCOOP) Program is a multi-institution collaboration implementing a modular, distributed service-oriented architecture for real time prediction and visualization of the impacts of extreme atmospheric events. The modular infrastructure enables real-time prediction of multi- scale, multi-model, dynamic, data-driven applications. SURA institutions are working together to create a virtual and distributed laboratory integrating coastal models, simulation data, and observations with computational resources and high speed networks. The loosely coupled architecture allows teams of computer and coastal scientists at multiple institutions to innovate complex system components that are interconnected with relatively stable interfaces. The operational system standardizes at the interface level to enable substantial innovation by complementary communities of coastal and computer scientists. This architectural philosophy solves a long-standing problem associated with the transition from research to operations. The SCOOP Program thereby implements a prototype laboratory consistent with the vision of a national, multi-agency initiative called the Integrated Ocean Observing System (IOOS). Several service- oriented components of the SCOOP enterprise architecture have already been designed and implemented, including data archive and transport services, metadata registry and retrieval (catalog), resource management, and portal interfaces. SCOOP partners are integrating these at the service level and implementing reconfigurable workflows for several kinds of user scenarios, and are working with resource providers to prototype new policies and technologies for on-demand computing.
Predicting Arrival Of Protons Emitted In Solar Flares
NASA Technical Reports Server (NTRS)
Spagnuolo, John N., Jr.; Schwuttke, Ursula M.; Han, Cecilia S.; Hervias, Felipe
1996-01-01
Visual Utility for Localization of Corona Accelerated Nuclei (VULCAN) computer program provides both advance warnings and insight for post-event analyses of effects of solar flares. Using measurements of peak fluxes, times of detection, flare location, solar wind velocities, and x-ray emissions from Sun, as electronically sent by NOAA (National Oceanographic and Atmospheric Administration), VULCAN predicts resulting intensities of proton fluxes at various user-chosen points (spacecraft or planets) of solar system. Also predicts times of onset of fluxes of protons and peak values of fluxes.
A life prediction model for laminated composite structural components
NASA Technical Reports Server (NTRS)
Allen, David H.
1990-01-01
A life prediction methodology for laminated continuous fiber composites subjected to fatigue loading conditions was developed. A summary is presented of research completed. A phenomenological damage evolution law was formulated for matrix cracking which is independent of stacking sequence. Mechanistic and physical support was developed for the phenomenological evolution law proposed above. The damage evolution law proposed above was implemented to a finite element computer program. And preliminary predictions were obtained for a structural component undergoing fatigue loading induced damage.
Toward more environmentally resistant gas turbines: Progress in NASA-Lewis programs
NASA Technical Reports Server (NTRS)
Lowell, C. E.; Grisaffe, S. J.; Levine, S. R.
1976-01-01
A wide range of programs are being conducted for improving the environmental resistance to oxidation and hot corrosion of gas turbine and power system materials. They range from fundamental efforts to delineate attack mechanisms, allow attack modeling and permit life prediction, to more applied efforts to develop potentially more resistant alloys and coatings. Oxidation life prediction efforts have resulted in a computer program which provides an initial method for predicting long time metal loss using short time oxidation data by means of a paralinear attack model. Efforts in alloy development have centered on oxide-dispersion strengthened alloys based on the Ni-Cr-Al system. Compositions have been identified which are compromises between oxidation and thermal fatigue resistance. Fundamental studies of hot corrosion mechanisms include thermodynamic studies of sodium sulfate formation during turbine combustion. Information concerning species formed during the vaporization of Na2SO4 has been developed using high temperature mass spectrometry.
Naeser, M A; Baker, E H; Palumbo, C L; Nicholas, M; Alexander, M P; Samaraweera, R; Prete, M N; Hodge, S M; Weissman, T
1998-11-01
To test whether lesion site patterns in patients with chronic, severe aphasia who have no meaningful spontaneous speech are predictive of outcome following treatment with a nonverbal, icon-based computer-assisted visual communication (C-ViC) program. Retrospective study in which computed tomographic scans performed 3 months after onset of stroke and aphasia test scores obtained before C-ViC therapy were reviewed for patients after receiving C-ViC treatment. A neurology department and speech pathology service of a Department of Veterans Affairs medical center and a university aphasia research center. Seventeen patients with stroke and severe aphasia who began treatment with C-ViC from 3 months to 10 years after onset of stroke. Level of ability to use C-ViC on a personal computer to communicate. All patients with bilateral lesions failed to learn C-ViC. For patients with unilateral left hemisphere lesion sites, statistical analyses accurately discriminated between those who could initiate communication with C-ViC from those who were only able to answer directed questions. The critical lesion areas involved temporal lobe structures (Wernicke cortical area and the subcortical temporal isthmus), supraventricular frontal lobe structures (supplementary motor area or cingulate gyrus 24), and the subcortical medial subcallosal fasciculus, deep to the Broca area. Specific lesion sites were also identified for appropriate candidacy for C-ViC. Lesion site patterns on computed tomographic scans are helpful to define candidacy for C-ViC training, and to predict outcome level. A practical method is presented for clinical application of these lesion site results in combination with aphasia test scores.
Tonkin, Matthew J.; Tiedeman, Claire; Ely, D. Matthew; Hill, Mary C.
2007-01-01
The OPR-PPR program calculates the Observation-Prediction (OPR) and Parameter-Prediction (PPR) statistics that can be used to evaluate the relative importance of various kinds of data to simulated predictions. The data considered fall into three categories: (1) existing observations, (2) potential observations, and (3) potential information about parameters. The first two are addressed by the OPR statistic; the third is addressed by the PPR statistic. The statistics are based on linear theory and measure the leverage of the data, which depends on the location, the type, and possibly the time of the data being considered. For example, in a ground-water system the type of data might be a head measurement at a particular location and time. As a measure of leverage, the statistics do not take into account the value of the measurement. As linear measures, the OPR and PPR statistics require minimal computational effort once sensitivities have been calculated. Sensitivities need to be calculated for only one set of parameter values; commonly these are the values estimated through model calibration. OPR-PPR can calculate the OPR and PPR statistics for any mathematical model that produces the necessary OPR-PPR input files. In this report, OPR-PPR capabilities are presented in the context of using the ground-water model MODFLOW-2000 and the universal inverse program UCODE_2005. The method used to calculate the OPR and PPR statistics is based on the linear equation for prediction standard deviation. Using sensitivities and other information, OPR-PPR calculates (a) the percent increase in the prediction standard deviation that results when one or more existing observations are omitted from the calibration data set; (b) the percent decrease in the prediction standard deviation that results when one or more potential observations are added to the calibration data set; or (c) the percent decrease in the prediction standard deviation that results when potential information on one or more parameters is added.
Computer simulation of space charge
NASA Astrophysics Data System (ADS)
Yu, K. W.; Chung, W. K.; Mak, S. S.
1991-05-01
Using the particle-mesh (PM) method, a one-dimensional simulation of the well-known Langmuir-Child's law is performed on an INTEL 80386-based personal computer system. The program is coded in turbo basic (trademark of Borland International, Inc.). The numerical results obtained were in excellent agreement with theoretical predictions and the computational time required is quite modest. This simulation exercise demonstrates that some simple computer simulation using particles may be implemented successfully on PC's that are available today, and hopefully this will provide the necessary incentives for newcomers to the field who wish to acquire a flavor of the elementary aspects of the practice.
Validation of helicopter noise prediction techniques
NASA Technical Reports Server (NTRS)
Succi, G. P.
1981-01-01
The current techniques of helicopter rotor noise prediction attempt to describe the details of the noise field precisely and remove the empiricisms and restrictions inherent in previous methods. These techniques require detailed inputs of the rotor geometry, operating conditions, and blade surface pressure distribution. The purpose of this paper is to review those techniques in general and the Farassat/Nystrom analysis in particular. The predictions of the Farassat/Nystrom noise computer program, using both measured and calculated blade surface pressure data, are compared to measured noise level data. This study is based on a contract from NASA to Bolt Beranek and Newman Inc. with measured data from the AH-1G Helicopter Operational Loads Survey flight test program supplied by Bell Helicopter Textron.
Comparative analysis of economic models in selected solar energy computer programs
NASA Astrophysics Data System (ADS)
Powell, J. W.; Barnes, K. A.
1982-01-01
The economic evaluation models in five computer programs widely used for analyzing solar energy systems (F-CHART 3.0, F-CHART 4.0, SOLCOST, BLAST, and DOE-2) are compared. Differences in analysis techniques and assumptions among the programs are assessed from the point of view of consistency with the Federal requirements for life cycle costing (10 CFR Part 436), effect on predicted economic performance, and optimal system size, case of use, and general applicability to diverse systems types and building types. The FEDSOL program developed by the National Bureau of Standards specifically to meet the Federal life cycle cost requirements serves as a basis for the comparison. Results of the study are illustrated in test cases of two different types of Federally owned buildings: a single family residence and a low rise office building.
NASA Technical Reports Server (NTRS)
Homan, D. J.
1977-01-01
A computer program written to calculate the proximity aerodynamic force and moment coefficients of the Orbiter/Shuttle Carrier Aircraft (SCA) vehicles based on flight instrumentation is described. The ground reduced aerodynamic coefficients and instrumentation errors (GRACIE) program was developed as a tool to aid in flight test verification of the Orbiter/SCA separation aerodynamic data base. The program calculates the force and moment coefficients of each vehicle in proximity to the other, using the load measurement system data, flight instrumentation data and the vehicle mass properties. The uncertainty in each coefficient is determined, based on the quoted instrumentation accuracies. A subroutine manipulates the Orbiter/747 Carrier Separation Aerodynamic Data Book to calculate a comparable set of predicted coefficients for comparison to the calculated flight test data.
Program For Evaluation Of Reliability Of Ceramic Parts
NASA Technical Reports Server (NTRS)
Nemeth, N.; Janosik, L. A.; Gyekenyesi, J. P.; Powers, Lynn M.
1996-01-01
CARES/LIFE predicts probability of failure of monolithic ceramic component as function of service time. Assesses risk that component fractures prematurely as result of subcritical crack growth (SCG). Effect of proof testing of components prior to service also considered. Coupled to such commercially available finite-element programs as ANSYS, ABAQUS, MARC, MSC/NASTRAN, and COSMOS/M. Also retains all capabilities of previous CARES code, which includes estimation of fast-fracture component reliability and Weibull parameters from inert strength (without SCG contributing to failure) specimen data. Estimates parameters that characterize SCG from specimen data as well. Written in ANSI FORTRAN 77 to be machine-independent. Program runs on any computer in which sufficient addressable memory (at least 8MB) and FORTRAN 77 compiler available. For IBM-compatible personal computer with minimum 640K memory, limited program available (CARES/PC, COSMIC number LEW-15248).
Sarment: Python modules for HMM analysis and partitioning of sequences.
Guéguen, Laurent
2005-08-15
Sarment is a package of Python modules for easy building and manipulation of sequence segmentations. It provides efficient implementation of usual algorithms for hidden Markov Model computation, as well as for maximal predictive partitioning. Owing to its very large variety of criteria for computing segmentations, Sarment can handle many kinds of models. Because of object-oriented programming, the results of the segmentation are very easy tomanipulate.
Exploring Polypharmacology Using a ROCS-Based Target Fishing Approach
2012-01-01
target representatives. Target profiles were then generated for a given query molecule by computing maximal shape/ chemistry overlap between the query...molecule and the drug sets assigned to each protein target. The overlap was computed using the program ROCS (Rapid Overlay of Chemical Structures ). We...approaches in off-target prediction has been reviewed.9,10 Many structure -based target fishing (SBTF) approaches, such as INVDOCK11 and Target Fishing Dock
NASA Astrophysics Data System (ADS)
Wetzel, P. E.
1981-11-01
The performance of an active solar heating system added to a house in Denver, CO was compared with predictions made by the FCHART 4.0 computer program. The house featured 43.23 sq m of collectors with an ethylene-glycol/water heat transfer fluid, and a 3.23 cu m storage tank. The house hot water was preheated in the storage tank, and home space heat was furnished whenever the storage water was above 32 C. Actual meteorological and heating demand data were used for the comparison, rather than long-term averages. Although monthly predictions by the FCHART program were found to diverge from measured data, the annual demand and supply predictions provided a good fit, i.e. within 9%, and were within 1% of the measured solar energy contributed to storage.
Aggregating Data for Computational Toxicology Applications ...
Computational toxicology combines data from high-throughput test methods, chemical structure analyses and other biological domains (e.g., genes, proteins, cells, tissues) with the goals of predicting and understanding the underlying mechanistic causes of chemical toxicity and for predicting toxicity of new chemicals and products. A key feature of such approaches is their reliance on knowledge extracted from large collections of data and data sets in computable formats. The U.S. Environmental Protection Agency (EPA) has developed a large data resource called ACToR (Aggregated Computational Toxicology Resource) to support these data-intensive efforts. ACToR comprises four main repositories: core ACToR (chemical identifiers and structures, and summary data on hazard, exposure, use, and other domains), ToxRefDB (Toxicity Reference Database, a compilation of detailed in vivo toxicity data from guideline studies), ExpoCastDB (detailed human exposure data from observational studies of selected chemicals), and ToxCastDB (data from high-throughput screening programs, including links to underlying biological information related to genes and pathways). The EPA DSSTox (Distributed Structure-Searchable Toxicity) program provides expert-reviewed chemical structures and associated information for these and other high-interest public inventories. Overall, the ACToR system contains information on about 400,000 chemicals from 1100 different sources. The entire system is built usi
NASA Technical Reports Server (NTRS)
Sinha, Neeraj; Brinckman, Kevin; Jansen, Bernard; Seiner, John
2011-01-01
A method was developed of obtaining propulsive base flow data in both hot and cold jet environments, at Mach numbers and altitude of relevance to NASA launcher designs. The base flow data was used to perform computational fluid dynamics (CFD) turbulence model assessments of base flow predictive capabilities in order to provide increased confidence in base thermal and pressure load predictions obtained from computational modeling efforts. Predictive CFD analyses were used in the design of the experiments, available propulsive models were used to reduce program costs and increase success, and a wind tunnel facility was used. The data obtained allowed assessment of CFD/turbulence models in a complex flow environment, working within a building-block procedure to validation, where cold, non-reacting test data was first used for validation, followed by more complex reacting base flow validation.
ERIC Educational Resources Information Center
Marcovitz, Alan B., Ed.
Four computer programs written in FORTRAN and BASIC develop theoretical predictions and data reduction for a junior-senior level heat exchanger experiment. Programs may be used at the terminal in the laboratory to check progress of the experiment or may be used in the batch mode for interpretation of final information for a formal report. Several…
A Computer Program for the Prediction of Solid Propellant Rocket Motor Performance. Volume 3
1975-07-01
following losses: two-dimensional/two-phase (coupled), nozzle erosion, kinetics, boundary layer, combustion efficiency, submergence . The program...loss •Two dimensional or divergence less •Finite Rate Kinetics loss •Boundary Layer Loss •Combustion Efficiency - • Submergence Loss •Erosion...counted twice. The iforcmcr.tioned assumptions are describ- ed In Section US, The submergence efficiency, ijgno* ^* rased on an empirical
ToxCast: Using high throughput screening to identify profiles of biological activity
ToxCast, the United States Environmental Protection Agency’s chemical prioritization research program, is developing methods for utilizing computational chemistry and bioactivity profiling to predict potential for toxicity and prioritize limited testing resources (www.epa.gov/toc...
Applications of high throughput screening to identify profiles of biological activity
ToxCast, the United States Environmental Protection Agency’s chemical prioritization research program, is developing methods for utilizing computational chemistry and bioactivity profiling to predict potential for toxicity and prioritize limited testing resources (www.epa.gov/toc...
FHWA Traffic Noise Model user's guide (version 2.0 addendum).
DOT National Transportation Integrated Search
2002-03-01
In March 1998, the Federal Highway Administration (FHWA) Office of Natural : Environment, released the FHWA Traffic Noise Model (FHWA TNM) Version 1.0, a : state-of-the-art computer program for highway traffic noise prediction and : analysis. Since t...