Engineering Papers⌕ Search

SEARCH · Engineering Papers

Results for “Image processing”

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 1,225 records · Page 68
All sourcesNASA NTRSDOE OSTI
NASA NTRS1982

Cloud cover estimation: Use of GOES imagery in development of cloud cover data base for insolation assessment

The potential of using digital satellite data to establish a cloud cover data base for the United States, one that would provide detailed information on the temporal and spatial variability of cloud development are studied. Key elements include: (1) interfacing GOES data from the University of Wisconsin Meteorological Data Facility with the Jet Propulsion Laboratory's VICAR image processing system and IBIS geographic information system; (2) creation of a registered multitemporal GOES data base; (3) development of a simple normalization model to compensate for sun angle; (4) creation of a variable size georeference grid that provides detailed cloud information in selected areas and summarized information in other areas; and (5) development of a cloud/shadow model which details the percentage of each grid cell that is cloud and shadow covered, and the percentage of cloud or shadow opacity. In addition, comparison of model calculations of insolation with measured values at selected test sites was accomplished, as well as development of preliminary requirements for a large scale data base of cloud cover statistics.

Huning, J. R.↗
NASA NTRS1981

Lake trophic applications: Wisconsin

Efforts to classify the water quality characteristics of lakes using LANDSAT imagery are reported. Image processing and registration techniques are described. A lake classification scheme which involves the assignment of a trophic class number was used in the data analysis. The resulting values were compared to the corresponding rank assignment derived from field measurements.

Scarpace, F.↗
NASA NTRS1983

LANDSAT-4 multispectral scanner (MSS) subsystem radiometric characterization

The multispectral band scanner (mass) and its spectral characteristics are described and methods are given for relating video digital levels on computer compatible tapes to radiance into the sensor. Topics covered include prelaunch calibration procedures and postlaunch radiometric processng. Examples of current data resident on the MSS image processing system are included. The MSS on LANDSAT 4 is compared with the scanners on earlier LANDSAT satellites.

Alford, W.↗
NASA NTRS1983

STS-3 Snowflake study

Videotape recordings were made of particles observed being released from the orbiter and image processing techniques were used to reduce the data in order to obtain sources and sizes. Results show that a significant number of 1 mm to 1 cm diameter particles were in the vicinity of STS-3. Their origin may be near the aft end of the orbiter; however, 19 of the 33 examined trajectories show that the origin was definitely forward of the aft end of the bay. There may be larger particles near the aft end of the orbiter. Most particles move generally rearward with respect to the orbiter (+X direction).

Barengoltz, J.↗
NASA NTRS1983

Proceedings of the NASA/MPRIA Workshop: Pattern Recognition

Outlines of talks presented at the workshop conducted at Texas A & M University on February 3 and 4, 1983 are presented. Emphasis was given to the application of Mathematics to image processing and pattern recognition.

Guseman, L. F., Jr.↗
NASA NTRS1982

Interactive initialization of heat flux parameters for numerical models using satellite temperature measurements

A method for obtaining patterns of moisture availability (and net evaporation) from satellite infrared measurements employs Carlson's boundary layer model and a variety of image processing routines executed by a minicomputer. To test the method with regard to regional scale moisture analyses, two case studies were chosen because of the availability of HCMM data and because of the presence of a large horizontal gradient in antecedent precipitation and crp moisture index. Results show some correlation in both cases between antecedent precipitation and derived moisture availability. Apparently, regional-scale moisture availability patterns can be determined with some degree of fidelity but the values themselves may be useful only in the relative sense and significant to within plus or minus one category of dryness over a range of 4 or 5 categories between absolutely dry and field saturation. Preliminary results suggest that the derived moisture values correlate best with longer-term precipitation totals, suggesting that the infrared temperatures respond more sensitively to a relatively deep substrate layer.

Carlson, T. N.↗
NASA NTRS1983

Study of LANDSAT-D thematic mapper performance as applied to hydrocarbon exploration

Improved delineation of known oil and gas fields in southern Ontario and a spectacularly high amount of structural information on the Owl Creek, Wyoming scene were obtained from analysis of TM data. The use of hue, saturation, and value image processing techniques on a Death Valley, California scene permitted direct comparison of TM processed imagery with existing 1:250,000 scale geological maps of the area and revealed small outcrops of Tertiary volcanic material overlying Paleozoic sections. Analysis of TM data over Lawton, Oklahoma suggests that the reducing chemical environment associated with hydrocarbon seepage change ferric iron to soluble ferrous iron, allowing it to be leached. Results of the band selection algorithm show a suprising consistency, with the 1,4,5 combination selected as optimal in most cases.

Everett, J. R.↗
NASA NTRS1983

Local governments LANDSAT applications program

The approach used to develop the internal capabilities of local governments to handle and evaluate LANDSAT data included remote sensing training, development of a low-cost digital image processing system, and technical assistance. Cost sharing, program management and coordination, and networking were also employed to address problems related to land use, water resources, environmental assessment, and air quality as experienced by urban planners. Local experiences gained in Atlanta, Georgia; Henrico County, Virginia; Oklahoma City; Oklahoma; and San Jose, California are described. Policy recommendations formulated for transferring remote sensing technologies to local governments are included.

Source record↗
NASA NTRS1983

Shear zone ice deformation using supervised analysis of Seasat data

Spacecraft and aircraft Synthetic-Aperture Radar (SAR) images are commonly used to compute sea ice conditions including especially the drift velocities of ice features. Recent developments, described in this paper, in computer-aided analysis and in digital image processing have extended the analysis speed and accuracy of registration to the point that ice deformation can be examined on the geophysically important scales of about 100 m over tens of kilometers between two 'snapshots.' Examples are shown for the ice motion and rotation in the shear zone near the Alaska coast from Seasat data in 1978.

Carsey, F.↗
NASA NTRS1983

A noninteractive procedure for land-use determination

A complete operational procedure designed for use by the U.S. Army Corps of Engineers for the determination of land-use information for hydrologic planning purposes is reported. The procedure combines photo interpretation techniques and the batch-mode computer analysis of Landsat digital data. Since the operational constraints preclude the use of dedicated, interactive image processing facilities, several novel approaches to geometric correction, classification, and data input/output were developed. The procedure is summarized, and examples of the application of the procedure to urban watersheds are described. In spite of the constraints, the procedure provides results comparable in accuracy and lower in cost than those provided by commercial services using interactive techniques.

Ford, G. E.↗
NASA NTRS1982

Galileo Institute for Astronomy (IFA) charge-coupled device (CCD) system

A fully portable self-contained charge-coupled device system has been constructed for shared use with the Galileo Project Imaging Team. The detector currently incorporated in the system is a Texas Instruments 500 x 500 three-phase CCD that has been thinned to operate in the backside illuminated mode. The detector and camera mainframe electronics were provided by the Jet Propulsion Laboratory. The support electronics and control interfaces necessary to operate the mainframe were constructed. The data system, which is built around a DeAnza Visacom VC-5000 Image Processor with an imbedded LSI-11 minicomputer, was also integrated. The capability to do image processing in real-time at the telescope has proved to be extremely valuable. The overall system read noise has been measured at 25 electrons. Full-well capacity is 40,000 electrons. Some results from laboratory tests and initial observing runs at the Mauna Kea 2.2-m telescope are presented.

Hlivak, R. J.↗
NASA NTRS1982

1982 International Geoscience and Remote Sensing Symposium, Munich, West Germany, June 1-4, 1982, Digest. Volumes 1 & 2

Theoretical and experimental data which have defined and/or extended the effectiveness of remote sensing operations are explored, with consideration given to both scientific and commercial activities. The remote sensing of soil moisture, the sea surface, and oil slicks is discussed, as are programs using satellites for studying geodynamics and geodesy, currents and waves, and coastal zones. NASA, Canadian, and Japanese radar and microwave passive and active systems are described, together with algorithms and techniques for image processing and classification. The SAR-580 project is outlined, and attention is devoted to satellite applications in investigations of the structure of the atmosphere, agriculture and land use, and geology. Design and performance features of various optical scanner, radar, and multispectral data processing systems and procedures are detailed.

Source record↗
NASA NTRS1983

A nebula around Nova BT Monocerotis

H-alpha observations of Nova BT Mon obtained on December 15, 1981 using an 800x800-pixel CCD detector on the double spectrograph of the 5-m Hale telescope at Palomar Observatory are reported. The reciprocal dispersion at H-alpha was 6.04 A/pixel and the angular scale along the 1.0-arcsec-wide east-west slit was 0.58 arcsec/pixel; resolution of the combined, processed image is about 12 A. A ring-shaped nebular emission with a center displaced slightly from the stellar image and an expansion distance to BT Mon of about 1800 pc was detected. The velocity diameter is found to be about 1500 km/sec along the ridge line and 2100 km/sec along the 10-unit contour. The mass of the visible nebula is estimated as 0.00003 solar mass, similar to the BT Mon ejection mass determined by Schaefer and Patterson (1983).

Marsh, T. R.↗
NASA NTRS1985

Fast Two-Dimensional Digital-Filter Hardware

Report describes priciples of hardware implementation of two-dimensional 5 by 5 convolute-integer low pass filter. Filter processes image data points fast enough for real-time use in image analysis and enhancement.

Edwards, T. R.↗
NASA NTRS1983

Antimisting fuel breakup and flammability

The breakup behavior and flammability of antimisting turbine fuels subjected to aerodynamic shear are investigated. Fuels tested were Jet A containing 0.3% FM-9 polymer at various levels of degradation ranging from virgin AMK to neat Jet A. The misting behavior of the fuels was quantified by droplet size distribution measurements. A technique based on high resolution laser photography and digital image processing of photographic records for rapid determination of droplet size distribution was developed. The flammability of flowing droplet-air mixtures was quantified by direct measurements of temperature rise in a flame established in the wake of a continuous ignition source. The temperature rise measurements were correlated with droplet size measurements. The flame anchoring phenomenon associated with the breakup of a liquid fuel in the wake of bluff body was shown to be important in the context of a survivable crash scenario. A pass/fail criterion for flammability testing of antimisting fuels, based on this flame-anchoring phenomenon, was proposed. The role of various ignition sources and their intensity in ignition and post-ignition behavior of antimisting fuels was also investigated.

Parikh, P.↗
NASA NTRS1984

Study of spectral/radiometric characteristics of the thematic mapper for land use applications

The previous characterization of scan-related low-frequency noise was confirmed and extended through analysis of reflective-band data from another nighttime acquisition. Amplitude and phase relationships of the level shifts were determined for each detector in each of free full frames. Analysis of scan-direction-related signal droop effects in nighttime data from the reflective bands was begun with encouraging initial observations. Also, an effort to characterize high-frequency noise in the reflective bands through Fourier analysis of nighttime data was initiated. Recommendations are made relative to the choice of radiometric calibration constants in the thematic mapper image processing system for the routine processing of TM data. Non-linear (piece-wise linear) calibration curves are recommended.

Malila, W. A.↗
NASA NTRS1984

Shot noise limited detection of OH using the technique of laser induced fluorescence

Nearly shot-noise limited detection of OH using the technique of laser-induced fluorescence is reported. A LIDAR configuration is used to excite fluorescence in a large volume and a narrow-bandwidth interference filter provides spectral discrimination. This arrangement alleviates the effect of ozone interference and facilitates image processing at relatively close distances. The detection limit is determined mainly by the shot-noise of the solar background. Ground-based measurements in Dearborn indicate a detection limit of better than 1 x 10 to the 6th power OH/cubic cm over a forty-minute acquisition period. Under favorable conditions, a comparable detection limit was also observed for airborne measurements.

Bakalyar, D. M.↗