Engineering Papers⌕ Search

SEARCH · Engineering Papers

Results for “Data Plotting”

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.

Quote a phrase for an exact phrase match. Source license links do not imply unrestricted reuse.

At least 739 records · Page 41
All sourcesNASA NTRSDOE OSTI
NASA NTRS1980

Satellite Power Systems (SPS) concept definition study. Volume 6: In-depth element investigation

The fabrication parameters of GaAs MESFET solid-state amplifiers considering a power added conversion efficiency of at least 80% and power gains of at least 10dB were determined. Operating frequency was 2.45 GHz although 914 MHz was also considered. Basic circuit to be considered was either Class C or Class E amplification. Two modeling programs were utilized. The results of several computer calculations considering differing loads, temperatures, and efficiencies are presented. Parametric data in both tabular and plotted form are presented.

Hanley, G. M.↗
NASA NTRS1980

Microwave radiometer measurements of soil moisture content

A unique set of radiometer measurements is presented, recorded during a 1000-h day and night monitoring of irrigated fields from fully saturated to completely dry. Radiometer measurements were recorded at 2.8-cm (X-band) and 21.4-cm (L-band) wavelengths for a range of incident angles from nadir to 50 deg. Soil moisture and soil temperature profile measurements were recorded to a depth of 15 cm. The test site was located in east-central Texas on a clay soil (Miller clay). Three bare-surface plots were used, each having a distinctly different surface roughness. Vegetated plots were also measured. The data quantify the sensitivity of microwave radiometer measurements to soil moisture variations, the effect of surface roughness on the measurement, and the influence of surface vegetation.

Newton, R. W.↗
NASA NTRS1982

Production of CS and S in Comet Bradfield /1979 X/

High and low resolution ultraviolet spectra of carbon monosulfide (CS) in Comet Bradfield (1979 X) were obtained with the IUE satellite. The high resolution rotational profile of the (0, 0) band at 257.5 nm can be fitted with a theoretical profile derived assuming a Boltzmann temperature of 70 K. Spatial plots of the low resolution data for both S and CS show that these emissions are concentrated toward the cometary nucleus. The results that have been obtained are consistent with a Haser model for CS and S where the parent molecule is CS2. A very rapid variation of CS brightness with heliocentric distance is found.

Jackson, W. M.↗
NASA NTRS1984

Algorithm for Constructing Contour Plots

General computer algorithm developed for construction of contour plots. algorithm accepts as input data values at set of points irregularly distributed over plane. Algorithm based on interpolation scheme: points in plane connected by straight-line segments to form set of triangles. Program written in FORTRAN IV.

Johnson, W.↗
NASA NTRS1984

Elliptical Orbit Performance Computer Program

Elliptical Orbit Performance (ELOPE) computer program for analyzing orbital performance of space boosters uses orbit insertion data obtained from trajectory simulation to generate parametric data on apogee and perigee altitudes as function of payload data. Data used to generate presentation plots that display elliptical orbit performance capability of space booster.

Myler, T.↗
NASA NTRS1982

A Method for Peat Inventory Based on LANDSAT Data and Computerized Mapping

Wetlands were preliminarily delineated on a geometrically-corrected color composite map printed from digital LANDSAT data using a computerized color plotting system. A digital classification was performed to identify the location and extent of wetland types (e.g., open bog, types of treed fen and black spruce-alder swamp). A map is printed from the results of this classification using the computerized color plotter. This color-coded map, produced at several different scales, provides a basis for pre-selecting field sampling sites. Helicopter-aided spot sampling based on the LANDSAT-derived map was conducted over the entire 1700 sq km area of North Ontario. Traditional transect sampling was carried out over a portion of the area, so that the two methods could be compared. Spot sampling based on the LANDSAT-derived map was found to produce results virtually identical to those produced by the transect sampling technique, in approximately one-fifteenth of the time and with a proportionate reduction in cost.

Pala, S.↗
NASA NTRS1983

Experimental study of main rotor/tail rotor/airframe interactions in hover. Volume 1: Text and figures

To assist in identifying and quantifying the relevant parameters associated with the complex topic of main rotor/fuselage/tail rotor interference, a model scale hover test was conducted in the Model Rotor Hover Facility. The test was conducted using the basic model test rig, fuselage skins to represent a UH-60A BLACK HAWK helicopter, 4 sets of rotor blades of varying geometry (i.e., twist, airfoils and solidity) and a model tail rotor that could be relocated to give changes in rotor clearance (axially, laterally, and vertically), can't angle and operating model (pusher or tractor). The description of the models and the tests, data analysis and summary (including plots) are included. The customary system of units gas used for principal measurements and calculations. Expressions in both SI units and customary units are used with the SI units stated first and the customary units afterwords, in parenthesis.

Balch, D. T.↗
NASA NTRS1982

Petrologic variations in Apollo 16 surface soils

Source rock, maturation history and intrasite variation data are derived for the Apollo 16 regolith by comparing modal analyses of 15 surface soils with rake and rock sample data. Triangular source rock component plots show that Apollo 16 soils have similar source rocks that are well homogenized throughout the site. The site can be divided into three soil petrographic provinces. Central site soils are mature, well homogenized, and enriched in glass. They are probably the most typical Cayley Plains materials present. North Ray soils are immature to submature, containing North Ray ejecta. South Ray soils are mature, but contain small amounts of fresh impact melts and plagioclase, due perhaps to the breakdown of blocky South Ray ejecta. The different compositions and physical properties of North and South Ray ejecta support the hypothesis that the latter event excavated Cayley material, while the former excavated Descartes materials.

Houck, K. J.↗
NASA NTRS1983

Preliminary results of the first static calibration of the RSRA helicopter active-isolator rotor balance system

The helicopter version of the Rotor Systems Research Aircraft (RSRA) is designed to make simultaneous measurements of all rotor forces and moments in flight analogous to a wind tunnel balance. Loads are measured by a combination of load cells, strain gages, and hydropneumatic active isolators which use pressure gages to measure loads. Complete evaluation of system performance required calibration of the rotor force and moment measuring system when installed in the aircraft. Measurement system responses to rotor loads obtained during the first static calibration of the RSRA helicopter are plotted and discussed. Plots of the raw transducer data are included.

Acree, C. W., Jr.↗
NASA NTRS1984

Shear-layer correction after Amiet under consideration of additional temperature gradient. Working diagrams for correction of signals

Amiet's correction scheme for sound wave transmission through shear-layers is extended to incorporate the additional effects of different temperatures in the flow-field in the surrounding medium at rest. Within a parameter-regime typical for acoustic measurements in wind tunnels amplitude- and angle-correction is calculated and plotted systematically to provide a data base for the test engineer.

Dobrzynski, W.↗
NASA NTRS1984

The two-lobe structure of the distant (at least 200 earth radii) magnetotail

Data from a 5 mos ISEE-3 passage through the magnetotail at distances beyond 60 earth radii (ER) are examined statistically to determine the tail structure out to 238 ER, the extent of the lobe and plasmasheet deviations from normal positions. The data include field and electron plots and plasma temperatures and densities. The maximum thickness of the plasmasheet was found to be similar to near-earth conditions, i.e., 9-15 ER, and was accompanied by an N-S dimension of 53-59 ER. No filamentary structures were derived, and the two-lobe structure was preserved. Possible causes of the asymmetry between the N-S and E-W scales are discussed.

Tsurutani, B. T.↗
NASA NTRS1985

Evaluation of data obtained from atmospheric laser Doppler velocimeter

The Doppler lidar velocimeter produces a variety of kinds of data. Besides the line of sight velocity components, there are the reflected amplitudes and the Doppler widths. Computer graphics software for displaying these data was produced. Different methods of presentation are needed for the various items. A picture was produced as pictures are often the best way to gain understanding. The individual lidar scans form a crosshatch pattern. Thus one-dimensional measurements fit together to form a two-dimensional whole. A pair of velocity measurements at a point combine to form a wind measurement with direction and magnitude. This gives a forest of wind vectors. The goal is to find a recognizable pattern to these trees. Often it is necessary to show only part of the information. That is, show only the wind direction not its magnitude or reduce the wind to streamlines of air flow. In other cases data are reduced to contour plots. Just enough contour lines are included to show the picture described.

Keck, T. S.↗
NASA NTRS1986

Ground vibration test of an F-16 airplane with modified decoupler pylons

The decoupler pylon is a passive wing/store flutter suppression device. It was modified to reduce friction following initial flight tests. A ground vibration test was conducted on an F-16 aircraft loaded on each wing with a one-half-full (center bay empty) 370-gallon fuel tank mounted on a standard pylon, a GBU-8 store mounted on the decoupler pylon, and an AIM-9J missile mounted on a wingtip launcher. The test was conducted prior to flight tests with the modified pylon to determine modal frequencies, mode shapes, and structural damping coefficients. Data presented include frequency response plots, mode shape plots, and limited force-effect plots.

Cazier, F. W., Jr..↗
NASA NTRS1986

Modified US Army U-8F ground vibration test

The Dryden Flight Research Facility of NASA Ames Research Center conducted a ground vibration test on a modified U.S. Army U-8F airplane. Modifications included new engines, propellers, and engine-mounted truss assemblies. The ground vibration test was conducted using sine dwell, single-point random, and impact excitations. The test was performed to determine modal frequencies, mode shapes, and structural damping coefficients of the airframe and propeller with full and empty fuel tanks. The data presented include frequency response plots, rigid-body and structural modal frequencies, and mode shapes.

Kehoe, M. W.↗
NASA NTRS1986

Improvements in the Goddard balloon-borne lidar

The Goddard balloon-borne lidar system for the measurement of stratospheric ozone and the hydroxyl radical has made three additional flights since the last laser radar conference. On September 27, 1984, a flight was made from Palestine, Texas obtaining a measurement of hydroxyl diurnal variation at 36 km. These data are presented on the plot which shows hydroxyl concentration as a function of GMT for the range cell closest to the instrument. Local noon corresponds to 18 hours on the plot. The rapid drop in concentration after noon is not predicted by models of stratospheric chemistry. It may represent the effects of contamination of the sample volume by hydrocarbons outgassed from the balloon. The more recent flights on June 30, 1985, and December 6, 1985, focussed on measurements of concentration in the lower stratosphere (less than 30 km). The June flight succeeded in obtaining an average concentration measurement (1.8 + or - 0.0000018 molecules/cubic cm) over the altitude range 21 to 26 km. The December flight obtained measurements down to 24 km with a better signal-to-noise ratio than that obtained in June. Prospects for further improvement in sensitivity and absolute calibration will be discussed.

Heaps, W. S.↗
NASA NTRS1986

Data processing and case study analysis of thunderstorm studies

A case study analysis of the anvil top structure of a May 19,1984, thunderstorm was performed. Wind data were both listed and plotted as time series of direction, horizontal velocity, and vertical velocity. A two-dimensional display of the horizontal winds along the flight track was also provided. The microphysical, dynamic, and thermodynamic characteristics of the overshooting tops and the downwind cirrus anvil top were studied. This included spatial and temporal distributions of cloud particle types and concentrations, horizontal and vertical wind in the cloud and its vinicity, and profiles of thermodynamic parameters.

Poellot, M. R.↗
NASA NTRS1985

Post-flight BET products for the 2nd discovery entry, STS-19 (51-A)

The post-flight products for the second Discovery flight, STS-19 (51-A), are summarized. The inertial best estimate trajectory (BET), BT19D19/UN=169750N, was developed using spacecraft dynamic measurements from Inertial Measurement Unit 2 (IMU2) in conjunction with the best tracking coverage available for any of the earlier Shuttle entries. As a consequence of the latter, an anchor epoch was selected which conforms to an initial altitude of greater than a million feet. The Extended BET, ST19BET/UN=274885C, incorporated the previously mentioned inertial reconstructed state information and the Langley Atmospheric Information Retrieval System (LAIRS) atmosphere, ST19MET/UN=712662N, with some minor exceptions. Primary and back-up AEROBET reels are NK0165 and NK0201, respectively. This product was only developed over the lowermost 360 kft altitude range due to atmosphere problems but this relates to altitudes well above meaningful signal in the IMUs. Summary results generated from the AEROBET for this flight are presented with meaningful configuration and statistical comparisons from the previous thirteen flights. Modified maximum likelihood estimation (MMLE) files were generated based on IMU2 and the Rate Gyro Assembly/Accelerometer Assembly (RGA/AA), respectively. Appendices attached define spacecraft and physical constants utilized, show plots of the final tracking data residuals from the post-flight fit, list relevant parameters from the BET at a two second spacing, and retain for archival purpose all relevant input and output tapes and files generated.

Kelly, G. M.↗
NASA NTRS1987

Space station integrated wall design and penetration damage control

The analysis code BUMPER executes a numerical solution to the problem of calculating the probability of no penetration (PNP) of a spacecraft subject to man-made orbital debris or meteoroid impact. The codes were developed on a DEC VAX 11/780 computer that uses the Virtual Memory System (VMS) operating system, which is written in FORTRAN 77 with no VAX extensions. To help illustrate the steps involved, a single sample analysis is performed. The example used is the space station reference configuration. The finite element model (FEM) of this configuration is relatively complex but demonstrates many BUMPER features. The computer tools and guidelines are described for constructing a FEM for the space station under consideration. The methods used to analyze the sensitivity of PNP to variations in design, are described. Ways are suggested for developing contour plots of the sensitivity study data. Additional BUMPER analysis examples are provided, including FEMs, command inputs, and data outputs. The mathematical theory used as the basis for the code is described, and illustrates the data flow within the analysis.

Coronado, A. R.↗