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Search indexed NASA NTRS and DOE OSTI research on propulsion, heat transfer, battery materials and energy systems. Follow report and document links to the original sources.

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At least 199 records · Page 11
All sourcesNASA NTRSDOE OSTI
NASA NTRS1988

An unambiguous determination of the propagation of a compressional Pc 5 wave

A compressional Pc5 event observed by the ISEE-1 magnetometer and Medium Energetic Particle Experiment instrument on August 21 and 22, 1978, is examined. The propagation properties of the compressional waves were determined using a technique which utilizes the finite Larmor radius effects in the signature of the multichannel energetic ion detector. It is shown that this technique determines unambiguously the propagation characteristics of the wave in both the azimuthal and the radial directions in the plane perpendicular to the background magnetic field; the results remained valid even though heavy energetic ions with Larmor radii larger than proton Larmor radii were present in the plasma.

Lin, N.↗
NASA NTRS1984

General specifications for the development of a PC-based simulator of the NASA RECON system

The general specifications for the design and implementation of an IBM PC/XT-based simulator of the NASA RECON system, including record designs, file structure designs, command language analysis, program design issues, error recovery considerations, and usage monitoring facilities are discussed. Once implemented, such a simulator will be utilized to evaluate the effectiveness of simulated information system access in addition to actual system usage as part of the total educational programs being developed within the NASA contract.

Dominick, Wayne D.↗
NASA NTRS1984

Design criteria for a PC-based common user interface to remote information systems

A set of design criteria are presented which will allow the implementation of an interface to multiple remote information systems on a microcomputer. The focus of the design description is on providing the user with the functionality required to retrieve, store and manipulate data residing in remote information systems through the utilization of a standardized interface system. The intent is to spare the user from learning the details of retrieval from specific systems while retaining the full capabilities of each system. The system design includes multi-level capabilities to enhance usability by a wide range of users and utilizes microcomputer graphics capabilities where applicable. A data collection subsystem for evaluation purposes is also described.

Dominick, Wayne D.↗
NASA NTRS1985

PC-based Multiple Information System Interface (PC/MISI) design plan

The general design plan for the implementation of a common user interface to multiple remote information systems within a microcomputer-based environment is presented. The intent is to provide a framework for the development of detailed specifications which will be used as guidelines for the actual development of the system.

Dominick, Wayne D.↗
NASA NTRS1985

PC-based Multiple Information System Interface (PC/MISI) detailed design and implementation plan

The design plan for the personal computer multiple information system interface (PC/MISI) project is discussed. The document is intended to be used as a blueprint for the implementation of the system. Each component is described in the detail necessary to allow programmers to implement the system. A description of the system data flow and system file structures is given.

Dominick, Wayne D.↗
NASA NTRS1985

An overview of the evaluation plan for PC/MISI: PC-based Multiple Information System Interface

An initial evaluation plan for the personal computer multiple information system interface (PC/MISI) project is discussed. The document is intend to be used as a blueprint for the evaluation of this system. Each objective of the design project is discussed along with the evaluation parameters and methodology to be used in the evaluation of the implementation's achievement of those objectives. The potential of the system for research activities related to more general aspects of information retrieval is also discussed.

Dominick, Wayne D.↗
NASA NTRS1989

A user-friendly, menu-driven, language-free laser characteristics curves graphing program for desk-top IBM PC compatible computers

A facility was established that uses collected data and feeds it into mathematical models that generate improved data arrays by correcting for various losses, base line drift, and conversion to unity scaling. These developed data arrays have headers and other identifying information affixed and are subsequently stored in a Laser Materials and Characteristics data base which is accessible to various users. The two part data base: absorption - emission spectra and tabulated data, is developed around twelve laser models. The tabulated section of the data base is divided into several parts: crystalline, optical, mechanical, and thermal properties; aborption and emission spectra information; chemical name and formulas; and miscellaneous. A menu-driven, language-free graphing program will reduce and/or remove the requirement that users become competent FORTRAN programmers and the concomitant requirement that they also spend several days to a few weeks becoming conversant with the GEOGRAF library and sequence of calls and the continual refreshers of both. The work included becoming thoroughly conversant with or at least very familiar with GEOGRAF by GEOCOMP Corp. The development of the graphing program involved trial runs of the various callable library routines on dummy data in order to become familiar with actual implementation and sequencing. This was followed by trial runs with actual data base files and some additional data from current research that was not in the data base but currently needed graphs. After successful runs, with dummy and real data, using actual FORTRAN instructions steps were undertaken to develop the menu-driven language-free implementation of a program which would require the user only know how to use microcomputers. The user would simply be responding to items displayed on the video screen. To assist the user in arriving at the optimum values needed for a specific graph, a paper, and pencil check list was made available to use on the trial runs.

Klutz, Glenn↗
NASA NTRS1990

PC-compatible computer-generated stimuli for video-task testing

A program for automatic computer generation of novel nonverbal stimuli is described. The program, STIMGEN, allows menu-driven control over the type and appearance of stimuli. Data are presented in which two monkeys matched to sample with high accuracy using stimuli generated with STIMGEN. These data are interpreted to support the usefulness and value of automatic stimulus generation in a variety of applications.

Washburn, David A.↗
NASA NTRS1990

A statistical study of Pc 3-5 pulsations observed by the AMPTE/CCE magnetic fields experiment. I - Occurrence distributions

A classification system based on dynamic power spectra of AMPTE/CCE magnetic field data has been developed which allows semiquantitative specification of pulsation activity at all times. Fifteen months of 6.24-s AMPTE/CCE magnetic field data have been analyzed using this scheme to generate a comprehensive data base of all pulsation activity observed from L = 5 to L = 9 at all local times in the frequency range 0-80 mHz. The pulsation divide naturally into five basic categories: toroidal fundamental mode resonances, toroidal harmonic resonances, compressional low-frequency waves, radially polarized waves, and disturbed intervals. Additional distinctions among members of these classes are made to arrive at 14 categories which describe 95 percent of the pulsations observed. Normal spatial distributions in local time and L shell are determined for each category. Magnetic latitude distributions are determined for four coherent categories of activity.

Anderson, B. J.↗
NASA NTRS1990

PC tools for project management: Programs and the state-of-the-practice

The use of microcomputer tools for NASA project management; which features are the most useful; the impact of these tools on job performance and individual style; and the prospects for new features in project management tools and related tools are addressed. High, mid, and low end PM tools are examined. The pro's and con's of the tools are assessed relative to various tasks. The strengths and weaknesses of the tools are presented through cases and demonstrations.

Bishop, Peter C.↗
NASA NTRS1991

ETARA PC version 3.3 user's guide: Reliability, availability, maintainability simulation model

A user's manual describing an interactive, menu-driven, personal computer based Monte Carlo reliability, availability, and maintainability simulation program called event time availability reliability (ETARA) is discussed. Given a reliability block diagram representation of a system, ETARA simulates the behavior of the system over a specified period of time using Monte Carlo methods to generate block failure and repair intervals as a function of exponential and/or Weibull distributions. Availability parameters such as equivalent availability, state availability (percentage of time as a particular output state capability), continuous state duration and number of state occurrences can be calculated. Initial spares allotment and spares replenishment on a resupply cycle can be simulated. The number of block failures are tabulated both individually and by block type, as well as total downtime, repair time, and time waiting for spares. Also, maintenance man-hours per year and system reliability, with or without repair, at or above a particular output capability can be calculated over a cumulative period of time or at specific points in time.

Hoffman, David J.↗
NASA NTRS1991

HF radar observations of Pc 5 field line resonances in the midnight/early morning MLT sector

The technique of F region sounding by HF coherent radar is applied to the study of field line resonances equatorward of a region of shear flow in the early morning sector. The motions were predominantly in the geomagnetic east-west direction, indicating north-south electric fields. These oscillations had pronounced peaks in their latitudinal power distribution. For the pulsation at 1.95 mHz, a latitudinal phase shift of 180 deg was observed across the peaks in all the look directions of the radar, and a longitudinal wavelength corresponding to an m value of 3 was obtained. For the 2.6-mHz pulsation, the phase shifts across the peaks had a variation with a look direction that indicated a significant longitudinal as well as latitudinal variation; for this activity, an m value of about 16 is estimated. These features are interpreted in terms of the field line resonance theory, and the possible sources of the pulsation energy are discussed.

Ruohoniemi, J. M.↗
NASA NTRS1990

PC programs for the prediction of the linear stability behavior of liquid propellant propulsion systems and application to current MSFC rocket engine test programs, volume 1

Research on propulsion stability (chugging and acoustic modes), and propellant valve control was investigated. As part of the activation of the new liquid propulsion test facilities, it is necessary to analyze total propulsion system stability. To accomplish this, several codes were built to run on desktop 386 machines. These codes enable one to analyze the stability question associated with the propellant feed systems. In addition, further work was adapted to this computing environment and furnished along with other codes. This latter inclusion furnishes those interested in high frequency oscillatory combustion behavior (that does not couple to the feed system) a set of codes for study of proposed liquid rocket engines.

Doane, George B., III↗
NASA NTRS1991

A PC-based inverse design method for radial and mixed flow turbomachinery

An Inverse Design Method suitable for radial and mixed flow turbomachinery is presented. The codes are based on the streamline curvature concept; therefore, it is applicable for current personal computers from the 286/287 range. In addition to the imposed aerodynamic constraints, mechanical constraints are imposed during the design process to ensure that the resulting geometry satisfies production consideration and that structural considerations are taken into account. By the use of Bezier Curves in the geometric modeling, the same subroutine is used to prepare input for both aero and structural files since it is important to ensure that the geometric data is identical to both structural analysis and production. To illustrate the method, a mixed flow turbine design is shown.

Skoe, Ivar Helge↗
NASA NTRS1991

CLIPS application user interface for the PC

The majority of applications that utilize expert system development programs for their knowledge representation and inferencing capability require some form of interface with the end user. This interface is more than likely an interaction through the computer screen. When building an application the user interface can prove to be the most difficult and time consuming aspect to program. Commercial products currently exist which address this issue. To keep pace C Language Integrated Production System (CLIPS) will need to find a solution for their lack of an easy to use Application User Interface (AUI). This paper represents a survey of the DoD CLIPS' user community and provides the backbone of a possible solution.

Jenkins, Jim↗
NASA NTRS1992

A PC-based collapse factor analysis for high pressure cryogenic systems

A collapse factor simulation computer program, suitable for use on personal computers, for supercritical cryogen system pressurization is examined. The available literature is previewed, individual component models are developed, and the overall simulation program logic is examined. Extensive use is made of existing thermodynamic and transport property evaluation packages. Heat transfer is estimated using natural convection correlations, and transient wall heat conduction is considered. Examples of the simulation are demonstrated for two facilities. Partial validation is achieved by comparing the simulation output with data from an existing test facility. Preliminary results indicate that the collapse factors will seldom exceed 1.15 during supercritical operation of high-pressure cryogenic systems. Recommendations for improvements in the component models and the simulation are made.

Hodge, B. K.↗
NASA NTRS1993

PC-SEAPAK

Interactive satellite data analysis software package developed for oceanographic research. Program used to process data from Nimbus-7 Coastal Zone Color Scanner and NOAA Advanced Very-High-Resolution Radiometer.

Mcclain, Charles R.↗