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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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Parts lists for the 2.25 GHz indoor- and antenna-unit assemblies are followed by drawings that constitute the drafting package for three converter types and the tunnel diode amplifier.
The process for manufacturing external tank dome gores is discussed. The test fixture and test procedure are described. The characteristics of the draw forming die are analyzed. The specific subjects included are: (1) forming, (2) trimming, (3) cleaning, and (4) heat treatment.
Models which can be used to accurately represent the type of line drawings which occur in teleconferencing and transmission for remote classrooms and which permit considerable data compression were described. The objective was to encode these pictures in binary sequences of shortest length but such that the pictures can be reconstructed without loss of important structure. It was shown that exploitation of reasonably simple structure permits compressions in the range of 30-100 to 1. When dealing with highly stylized material such as electronic or logic circuit schematics, it is unnecessary to reproduce configurations exactly. Rather, the symbols and configurations must be understood and be reproduced, but one can use fixed font symbols for resistors, diodes, capacitors, etc. Compression of pictures of natural phenomena such as can be realized by taking a similar approach, or essentially zero error reproducibility can be achieved but at a lower level of compression.
A FORTRAN V computer program, written for the UNIVAC 1100 series, is used to draw a variety of precision thermophysical property charts on the Calcomp plotter. In addition to the program (GASPLOT), which requires (15 160) sub 10 storages, a thermophysical properties routine needed to produce plots. The program is designed so that any two of the state variables, the derived variables, or the transport variables may be plotted as the ordinate - abscissa pair with as many as five parametric variables. The parameters may be temperature, pressure, density, enthalpy, and entropy. Each parameter may have as many a 49 values, and the range of the variables is limited only by the thermophysical properties routine.
This volume contains the figures and drawings reference in Volume 1.
The recovery of the three dimensional structure of visible surfaces depicted in an image by emphasizing the role of geometric cues present in line drawings, was studied. Three key components are line classification, line interpretation, and surface interpolation. A model for three dimensional line interpretation and surface orientation was refined and a theory for the recovery of surface shape from surface marking geometry was developed. A new approach to the classification of edges was developed and implemented signatures were deduced for each of several edge types, expressed in terms of correlational properties of the image intensities in the vicinity of the edge. A computer program was developed that evaluates image edges as compared with these prototype signatures.
A preliminary design effort directed toward a low concentration ratio photovoltaic array system based on 1984 technology and capable of delivering multi-hundred kilowatts (300 kW to 100 kW range) in low Earth orbit. The array system consists of two or more array modules each capable of delivering between 113 kW to 175 kW using silicon solar cells or gallium arsenide solar cells, respectively. The array module deployed area is 1320 square meters and consists of 4356 pyramidal concentrator elements. The module, when stowed in the Space Shuttle's payload bay, has a stowage volume of a cube with 3.24 meters on a side. The concentrator elements are sized for a geometric concentration ratio (GCR) of six with an aperture area of 0.5 meters x 0.5 meters. Drawings for the preliminary design configuration and for the test hardware that was fabricated for design evaluation and test are provided.
An implicit surface mathematical description of three-dimensional space is defined in terms of all points which satisfy some equation F(x, y, z) equals 0. This form is ideal for space-shaded picture drawing, where the coordinates are substituted for x and y and the equation is solved for z. A new algorithm is presented which is applicable to functional forms other than those of first- and second-order polynomial functions, such as the summation of several Gaussian density distributions. The algorithm was created in order to model electron density maps of molecular structures, but is shown to be capable of generating shapes of esthetic interest.
A novel calibration approach was used for Landsat 4 TM simulator data acquired at the Patrick Draw test site, Wyoming, where the 'true' reflectance spectrum for any pixel area cannot be practically determined because of mixing of spectral components. An empirically derived function was first applied to the scanner data to remove the brightness gradient due to directional scattering and surface geometry. Based on the observation that the distribution of scanner brightness values (DN) were Gaussian, the minimum, mean, and maximum DN for each band were extracted and plotted versus the similar percent reflectance values determined from a large representative collection of field reflectance data for the area. These plots provided linear transformations relating DN value to reflectance in each band.
The design, development and analysis of the 7.3 MW MOD-5A wind turbine generator is documented. Volume 4 contains the drawings and specifications that were developed in preparation for building the MOD-5A wind turbine generator. This is the first of five books of volume four. It contains structural design criteria, generator step-up transformer specs, specs for design, fabrication and testing of the system, specs for the ground control enclosure, systems specs, slip ring specs, and control system specs.
The design, development and analysis of the 7.3 MW MOD-5A wind turbine generator is documented. There are four volumes. This volume contains the drawings and specifications that were developed in preparation for building the MOD-5A wind turbine generator. This is the second book of volume four. Some of the items it contains are specs for the emergency shutdown panel, specs for the simulator software, simulator hardware specs, site operator terminal requirements, control data system requirements, software project management plan, elastomeric teeter bearing requirement specs, specs for the controls electronic cabinet, and specs for bolt pretensioning.
RULCHK computer program aids in structuring layers of information pertaining to part or assembly designed with software described in article "Software for Drawing Design Details Concurrently" (MFS-28444). Checks and optionally updates structure of layers for part. Enables designer to construct model and annotate its documentation without burden of manually layering part to conform to standards at design time.
SILHOUETTE is program for line drawings rendering any subset of polygons as silhouette. Program is improvement on, and replacement for, HIDDEN LINE COMPUTER CODE (ARC-11446). Offers combinations of silhouette and nonsilhouette specifications for arbitrary solid. Written in FORTRAN 77.
This report presents a discussion of how to determine the location of a line or surface from experimental data. What we desire to know practically is the number of ordinates required to obtain a certain probable precision in drawing a line or surface.
Acceptance data package - engineering drawings and associated lists for fabrication, assembly and maintenance (cleaning, fluidized bed coating, bounding and staking) motor/encoded solar x-ray imager (SXI) (Aeroflex p/n 16187) were given.
Presentation for FAA sponsored meeting to discuss time-based metering trial planning. This presentation describes the Dynamic Routes for Arrivals in Weather (DRAW) concept and the associated trial planning functionality.
A brief overview of the ATD-3 DRAW tool for assisting Traffic Management Coordinators with rerouting flights impacted by convective weather in a arrival- metered air traffic environment.
One or more embodiments relate to a method for controlling fiber growth and fiber diameter in a laser heated pedestal growth (LHPG) system so as to provide long, continuous single-crystal optical fibers of uniform diameter. The method generally provides three independent parameter feedback controls to control the molten zone height, laser power, and fiber drawing rates simultaneously in order to reduce the mismatch between instantaneous diameter changes and current diameter. The method permits the growth of fibers with non-uniform diameters along the fiber's length. The method also provides the capability to stop the LHPG system, remove the exhausted pedestal feedstock with a second pedestal feedstock, and restart the LHPG system to provide a continuous fiber.