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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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All sourcesNASA NTRSDOE OSTI
NASA NTRS1975

Advanced crew procedures development techniques

The development of an operational computer program, the Procedures and Performance Program (PPP), is reported which provides a procedures recording and crew/vehicle performance monitoring capability. The PPP provides real time CRT displays and postrun hardcopy of procedures, difference procedures, performance, performance evaluation, and training script/training status data. During post-run, the program is designed to support evaluation through the reconstruction of displays to any point in time. A permanent record of the simulation exercise can be obtained via hardcopy output of the display data, and via magnetic tape transfer to the Generalized Documentation Processor (GDP). Reference procedures data may be transferred from the GDP to the PPP.

Arbet, J. D.↗
NASA NTRS1981

Development techniques for generic software

In developing the first version of a generic implementation of X.25, Levels 2 and 3, three development techniques are examined: table driven finite state machine implementation, an integrated testing environment, and top down design. A finite state machine (FSM) is a powerful tool for both specifying and implementing protocols. This technique was used in the X.25 specification. A table driven implementation of the FSM was chosen to facilitate changes and simplify coding. The effect that this technique have on program size, speed of execution, coding time, and debugging time are investigated.

Hamilton, R. L.↗
NASA NTRS1975

Crew procedures development techniques

The study developed requirements, designed, developed, checked out and demonstrated the Procedures Generation Program (PGP). The PGP is a digital computer program which provides a computerized means of developing flight crew procedures based on crew action in the shuttle procedures simulator. In addition, it provides a real time display of procedures, difference procedures, performance data and performance evaluation data. Reconstruction of displays is possible post-run. Data may be copied, stored on magnetic tape and transferred to the document processor for editing and documentation distribution.

Arbet, J. D.↗
NASA NTRS1977

Environment effects from SRB exhaust effluents: Technique development and preliminary assessment

Techniques to determine the environmental effects from the space shuttle SRB (Solid Rocket Booster) exhaust effluents are used to perform a preliminary climatological assessment. The exhaust effluent chemistry study was performed and the exhaust effluent species were determined. A reasonable exhaust particle size distribution is constructed for use in nozzle analyses and for the deposition model. The preliminary assessment is used to identify problems that are associated with the full-scale assessment; therefore, these preliminary air quality results are used with caution in drawing conclusion regarding the environmental effects of the space shuttle exhaust effluents.

Goldford, A. I.↗
NASA NTRS1986

Novel measurement techniques (development and analysis of silicon solar cells near 20% effciency)

Work in identifying, developing, and analyzing techniques for measuring bulk recombination rates, and surface recombination velocities and rates in all regions of high-efficiency silicon solar cells is presented. The accuracy of the previously developed DC measurement system was improved by adding blocked interference filters. The system was further automated by writing software that completely samples the unkown solar cell regions with data of numerous recombination velocity and lifetime pairs. The results can be displayed in three dimensions and the best fit can be found numerically using the simplex minimization algorithm. Also described is a theoretical methodology to analyze and compare existing dynamic measurement techniques.

Wolf, M.↗
NASA NTRS1998

Cost and Schedule Analytical Techniques Development

This Final Report summarizes the activities performed by Science Applications International Corporation (SAIC) under contract NAS 8-40431 "Cost and Schedule Analytical Techniques Development Contract" (CSATD) during Option Year 3 (December 1, 1997 through November 30, 1998). This Final Report is in compliance with Paragraph 5 of Section F of the contract. This CSATD contract provides technical products and deliverables in the form of parametric models, databases, methodologies, studies, and analyses to the NASA Marshall Space Flight Center's (MSFC) Engineering Cost Office (PP03) and the Program Plans and Requirements Office (PP02) and other user organizations. Detailed Monthly Reports were submitted to MSFC in accordance with the contract's Statement of Work, Section IV "Reporting and Documentation". These reports spelled out each month's specific work performed, deliverables submitted, major meetings conducted, and other pertinent information. Therefore, this Final Report will summarize these activities at a higher level. During this contract Option Year, SAIC expended 25,745 hours in the performance of tasks called out in the Statement of Work. This represents approximately 14 full-time EPs. Included are the Huntsville-based team, plus SAIC specialists in San Diego, Ames Research Center, Tampa, and Colorado Springs performing specific tasks for which they are uniquely qualified.

Source record↗
NASA NTRS2004

TopMaker: Technique Developed for Automatic Multiblock Topology Generation Using the Medial Axis

The TopMaker technique was developed in an effort to reduce the time required for grid generation in complex numerical studies. Topology generation accounts for much of the man-hours required for structured multiblock grids. With regard to structured multiblock grids, topology refers to how the blocks are arranged and connected. A two-dimensional multiblock topology generation technique has been developed at the NASA Glenn Research Center. Very general configurations can be addressed by the technique. A configuration is defined by a collection of non-intersecting closed curves, which will be referred to as loops. More than a single loop implies that holes exist in the domain, which poses no problem. This technique requires only the medial vertices and the touch points that define each vertex. From the information about the medial vertices, the connectivity between medial vertices is generated. The physical shape of the medial edge is not required. By applying a few simple rules to each medial edge, a multiblock topology can be generated without user intervention. The resulting topologies contain only the level of complexity dictated by the configurations. Grid lines remain attached to the boundary except at sharp concave turns, where a change in index family is introduced as would be desired. Keeping grid lines attached to the boundary is especially important in computational fluid dynamics, where highly clustered grids are used near no-slip boundaries. This technique is simple and robust and can easily be incorporated into the overall grid-generation process.

Rigby, David L.↗
NASA NTRS1973

Interpretation techniques development

Processing, interpretation, classification, recognition, and enhancement techniques for use with ERTS-1 multispectral-imagery - Conference

Alford, W.↗
NASA NTRS2001

Sensitive Technique Developed Using Atomic Force Microscopy to Measure the Low-Earth-Orbit Atomic Oxygen Erosion of Polymers

A recession measurement technique has been developed at the NASA Glenn Research Center to determine the atomic oxygen durability of polymers exposed to the space environment for short durations. Polymers such as polyimide Kapton and Teflon FEP (fluorinated ethylene propylene, DuPont) are commonly used in spacecraft because of their desirable properties, such as flexibility, low density, and in the case of FEP, low solar absorptance and high thermal emittance. Polymers on the exterior of spacecraft in the low- Earth-orbit environment are exposed to energetic atomic oxygen, resulting in erosion and potential structural loss. It is, therefore, important to understand the atomic oxygen erosion yield (E, the volume loss per incident oxygen atom) of polymers being considered in spacecraft design. Because long-term space exposure data are rare and very costly, short-term exposures, such as on the space shuttles, are often relied on for atomic oxygen erosion determination. The most common technique for determining E is through mass-loss measurements. For limited-duration exposure experiments, such as shuttle flight experiments, the atomic oxygen fluence is often so small that mass-loss measurements are not sensitive enough. Therefore, a recession measurement technique has been developed at Glenn to obtain accurate erosion yields of polymers exposed to low atomic oxygen fluences.

deGroh, Kim D.↗
NASA NTRS2004

General-Purpose Stereo Imaging Velocimetry Technique Developed for Space and Industrial Applications

A new three-dimensional, full-field analysis technique has been developed for industrial and space applications. Stereo Imaging Velocimetry (SIV) will provide full-field analysis for three-dimensional flow data from any optically transparent fluid that can be seeded with tracer particles. The goal of SIV is to provide a means to measure three-dimensional fluid velocities quantitatively and qualitatively at many points. SIV is applicable to any optically transparent fluid experiment. Except for the tracer particles, this measurement technique is nonintrusive. Velocity accuracies are on the order of 95 to 99 percent of fullfield. The system components of SIV include camera calibration, centroid determination, overlap decomposition, particle tracking, stereo matching, and three-dimensional velocity analysis. SIV has been used successfully for space shuttle experiments as well as for fluid flow applications for business and industry.

McDowell, Mark↗
NASA NTRS2011

Off-Body Boundary-Layer Measurement Techniques Development for Supersonic Low-Disturbance Flows

Investigations were performed to develop accurate boundary-layer measurement techniques in a Mach 3.5 laminar boundary layer on a 7 half-angle cone at 0 angle of attack. A discussion of the measurement challenges is presented as well as how each was addressed. A computational study was performed to minimize the probe aerodynamic interference effects resulting in improved pitot and hot-wire probe designs. Probe calibration and positioning processes were also developed with the goal of reducing the measurement uncertainties from 10% levels to less than 5% levels. Efforts were made to define the experimental boundary conditions for the cone flow so comparisons could be made with a set of companion computational simulations. The development status of the mean and dynamic boundary-layer flow measurements for a nominally sharp cone in a low-disturbance supersonic flow is presented.

Owens, Lewis R.↗