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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
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NASA NTRS1975

Engineering studies of vectorcardiographs in blood pressure measuring systems, appendix 3

The following subjects were covered: (1) ASM80 manual, (2) signal preprocessing as an aid to on-line EKG analysis, and (3) high speed evaluation of magnetic tape recordings of electrocardiograms. A description of the ASM80 symbolic assembly program for the INTEL 8080 microprocessor and a user's manual were presented. The capability of three redundancy reduction algorithms to produce adequate representations of electrocardiographic data was examined. A hardware device was constructed which carried out zero order interpolation on a signal. Examination of the zero order interpolators reconstructed signal indicated that this representation was adequate for analysis of rhythm. A system to analyze magnetic tapes of electrocardiograms recorded over 24 hour intervals was designed. The recordings are sampled 200 times per second using a Nova computer and a special interface system. This system was tested on several recordings of clinical data, containing over 75 premature ventricular contractions, each one of which was flagged.

Mark, R. G.↗
NASA NTRS1975

A versatile data acquisition system for Goldstone

A data acquisition system set up at Goldstone was described. It is capable of recording a wide variety of parameters from widely separated geographical locations with varying integration times and recording speeds. It is fast, accurate, and modular in form so that it can be readily expanded. The accuracies of the system are discussed, and examples of data recorded with the system's capability of operation with preprocessing are given.

Reid, M. S.↗
NASA NTRS1975

Natural Resources Inventory and Land Evaluation in Switzerland

The author has identified the following significant results. A system was developed to operationally map and measure the areal extent of various land use categories for updating existing and producing new and actual thematic maps showing the latest state of rural and urban landscapes and its changes. The processing system includes: (1) preprocessing steps for radiometric and geometric corrections; (2) classification of the data by a multivariate procedure, using a stepwise linear discriminant analysis based on carefully selected training cells; and (3) output in form of color maps by printing black and white theme overlays of a selected scale with photomation system and its coloring and combination into a color composite.

Haefner, H.↗
NASA NTRS1975

Satellite on-board processing for earth resources data

Results of a survey of earth resources user applications and their data requirements, earth resources multispectral scanner sensor technology, and preprocessing algorithms for correcting the sensor outputs and for data bulk reduction are presented along with a candidate data format. Computational requirements required to implement the data analysis algorithms are included along with a review of computer architectures and organizations. Computer architectures capable of handling the algorithm computational requirements are suggested and the environmental effects of an on-board processor discussed. By relating performance parameters to the system requirements of each of the user requirements the feasibility of on-board processing is determined for each user. A tradeoff analysis is performed to determine the sensitivity of results to each of the system parameters. Significant results and conclusions are discussed, and recommendations are presented.

Bodenheimer, R. E.↗
NASA NTRS1975

Quantification of geologic lineaments by manual and machine processing techniques

A study was conducted to investigate the effect of operator variability and subjectivity in lineament mapping and to examine methods to minimize or eliminate these problems by use of several machine preprocessing methods. LANDSAT scenes from the Anadarko Basin of Oklahoma and the Colorado Plateau were analyzed as test cases. Four geologists mapped lineaments on an Anadarko Basin scene, using transparencies of MSS bands 4-7, and their results are compared statistically. The total number of fractures mapped by the operators and their average lengths varied considerably, although comparison of lineament directions revealed some consensus. A summary map (785 linears) produced by overlaying the maps generated by the four operators showed that only 0.4% were recognized by all four operators, 4.7% by three, 17.8% by two and 77% by one operator. Two methods of machine aided mapping were tested, both simulating directional filters. One consists of computer (digital) processing of CCTs using edge enhancement algorithms, the other employs a television (analog) scanning of an image transparency which superimposes the original image and one offset in the direction of the scan line.

Podwysocki, M. H.↗
NASA NTRS1975

Advances in automatic extraction of earth resources information from multispectral scanner data

The basis of spectral discrimination was briefly examined indicating sources of variability which tend to obscure the spectral attributes of the classes of interest. Spatial and temporal discrimination bases are also discussed. Automatic processing functions, techniques and methods, and equipment are discussed with emphasis on techniques and equipment required for operational large area surveys with satellite data. Techniques for carrying out major functions of preprocessing for signature extension, feature extraction, discrimination, display, and applications modeling were examined. A multiplicative and additive signature correction technique and a proportion estimation technique are discussed. The development of the multivariate interactive digital analysis system multispectral processor system which represents a breakthrough in cost effective high throughput processing for large area surveys from satellites and aircraft is reviewed. Applications and results are discussed briefly for agricultural crop inventories, environmental monitoring, and resources surveys from ERIM LANDSAT and EREP investigations to indicate the substantial progress achieved to date.

Erickson, J. D.↗
NASA NTRS1975

ERIPS: Earth Resource Interactive Processing System

The ERIPS is an interactive computer system used in the analysis of remotely sensed data. It consists of a set of software programs which are executed on an IBM System/360 Model 75J computer under the direction of a trained analyst. The software was a derivative of the Purdue LARSYS program and has evolved to include an extensive pattern recognition system and a number of manipulative, preprocessing routines which prepare the imagery for the pattern recognition application. The original purpose of the system was to analyze remotely sensed data, to develop and perfect techniques to process the data, and to determine the feasibility of applying the data to significant earth resources problems. The System developed into a production system. Error recovery and multi-jobbing capabilities were added to the system.

Quinn, M. J.↗
NASA NTRS1976

Results from the Crop Identification Technology Assessment for Remote Sensing (CITARS) project

The author has identified the following significant results. It was found that several factors had a significant effect on crop identification performance: (1) crop maturity and site characteristics, (2) which of several different single date automatic data processing procedures was used for local recognition, (3) nonlocal recognition, both with and without preprocessing for the extension of recognition signatures, and (4) use of multidate data. It also was found that classification accuracy for field center pixels was not a reliable indicator of proportion estimation performance for whole areas, that bias was present in proportion estimates, and that training data and procedures strongly influenced crop identification performance.

Bauer, M. E.↗
NASA NTRS1975

Crop identification technology assessment for remote sensing (CITARS). Volume 10: Interpretation of results

The CITARS was an experiment designed to quantitatively evaluate crop identification performance for corn and soybeans in various environments using a well-defined set of automatic data processing (ADP) techniques. Each technique was applied to data acquired to recognize and estimate proportions of corn and soybeans. The CITARS documentation summarizes, interprets, and discusses the crop identification performances obtained using (1) different ADP procedures; (2) a linear versus a quadratic classifier; (3) prior probability information derived from historic data; (4) local versus nonlocal recognition training statistics and the associated use of preprocessing; (5) multitemporal data; (6) classification bias and mixed pixels in proportion estimation; and (7) data with differnt site characteristics, including crop, soil, atmospheric effects, and stages of crop maturity.

Bizzell, R. M.↗
NASA NTRS1976

A methodology for small scale rural land use mapping in semi-arid developing countries using orbital imagery. Part 3: Review of land use surveys using orbital imagery in the USA

The author has identified the following significant results. Techniques of preprocessing, interpretation, classification, and ground truth sampling were studied. It has shown the need for a low cost, low level technology, viable, operational methodology to replace the emphasis given in the U.S. to machine processing, which many developing countries cannot afford, understand, nor implement.

Vangenderen, J. L.↗
NASA NTRS1976

A methodology for small scale rural land use mapping in semi-arid developing countries using orbital imagery. Part 5: Experimental and operational techniques of mapping land use

The author has identified the following significant results. Scope of the preprocessing techniques was restricted to standard material from the EROS Data Center accompanied by some enlarging procedures and the use of the diazo process. Investigation has shown that the most appropriate sampling strategy for this study is the stratified random technique. A viable sampling procedure, together with a method for determining minimum number of sample points in order to test results of any interpretation are presented.

Vangenderen, J. L.↗
NASA NTRS1975

ATS-6 - Preliminary results from the 13/18-GHz COMSAT Propagation Experiment

The 13/18-GHz COMSAT Propagation Experiment (CPE) is reviewed, the data acquisition and processing are discussed, and samples of preliminary results are presented. The need for measurements of both hydrometeor-induced attenuation statistics and diversity effectiveness is brought out. The facilitation of the experiment - CPE dual frequency and diversity site location, the CPE ground transmit terminals, the CPE transponder on Applications Technology Satellite-6 (ATS-6), and the CPE receive and data acquisition system - is briefly examined. The on-line preprocessing of the received signal is reviewed, followed by a discussion of the off-line processing of this database to remove signal fluctuations not due to hydrometeors. Finally, samples of the results of first-level analysis of the resultant data for the 18-GHz diversity site near Boston, Mass., and for the dual frequency 13/18-GHz site near Detroit, Mich., are presented and discussed.

Hyde, G.↗
NASA NTRS1975

Advances in automatic extraction of information from multispectral scanner data

The state-of-the-art of automatic multispectral scanner data analysis and interpretation is reviewed. Sources of system variability which tend to obscure the spectral characteristics of the classes under consideration are discussed, and examples of the application of spatial and temporal discrimination bases are given. Automatic processing functions, techniques and methods, and equipment are described with particular attention to those that are applicable to large land surveys using satellite data. The development and characteristics of the Multivariate Interactive Digital Analysis System (MIDAS) for processing aircraft or satellite multispectral scanning data are discussed in detail. The MIDAS system combines the parallel digital implementation capabilities of a low-cost processor with a general purpose PDP-11/45 minicomputer to provide near-real-time data processing. The preprocessing functions are user-selectable. The input subsystem accepts data stored on high density digital tape, computer compatible tape, and analog tape.

Erickson, J. D.↗
NASA NTRS1975

Satellite laser ranging work at the Goddard Space Flight Center

The paper describes the satellite laser ranging system at the Goddard Space Flight Center, its range and accuracy capabilities, and planned improvements for future systems. Major subsystems are described, including the laser, optical/mechanical, receiver, computer/software, timing, and laser data preprocessing subsystems. Operational considerations are examined, with attention given the mobile station layout, manpower requirements, and transportability. System performance is considered, with emphasis on system accuracy (calibration, stability, clock synchronization, atmospheric propagation correction) and range capability.

Mcgunigal, T. E.↗
NASA NTRS1977

Poor-resolution satellite observations of radar return from North America, Brazil, and the oceans

The 13.9 GHz radar scatterometer on Skylab produced statistics of radar returns from thousands of points in North America and Brazil, as well as from the oceans. The resolution cell of the system varied from about 11 km in diameter at vertical incidence to 20 by 30 km at 50 deg incidence. Although these cells are larger than the preprocessing cells to be expected from spacecraft synthetic-aperture radars, they are at least as comparable with such cells as are the observation cells when aircraft radars are used. Results are presented both in terms of composite statistics for North America, Brazil, and the oceans, and in terms of statistics for particular classes of terrain. Both vertical and horizontal polarization data are presented for the land, and cross-polarized measurements are presented as well as for the sea. Correlations are indicated for the returns at different angles and polarizations.

Moore, R. K.↗
NASA NTRS1976

The Boeing plastic analysis capability for engines

The current BOPACE program is described as a nonlinear stress analysis program, which is based on a family of isoparametric finite elements. The theoretical, user, programmer, preprocessing aspects are discussed, and example problems are included. New features in the current program version include substructuring, an out-of-core Gauss wavefront equation solver, multipoint constraints, combined material and geometric nonlinearities, automatic calculation of inertia effects, provision for distributed as well as concentrated mechanical loads, follower forces, singular crack-tip elements, the SAIL automatic generation capability, and expanded user control over input quantity definition, output selection, and program execution. BOPACE is written in FORTRAN 4 and is currently available for both the IBM 360/370 and the UNIVAC 1108 machines.

Vos, R. G.↗
NASA NTRS1976

Screwworm Eradication Data System (SEDS) applications program documentation, part 2

National Oceanic and Atmospheric Administration (NOAA) satellite data, which is in analog tape form, is converted into output data products. These products are used by investigators in determining optimum areas for airdrops of steril screwworm flies over Mexico. The output product of SEDS takes the form of imagery data film slides showing Mexico and the lower southwest portion of the United States. The area analog preprocessing phase of the SEDS task is covered.

Source record↗
NASA NTRS1977

Feasibility investigation of integrated optics Fourier transform devices

The possibility of producing an integrated optics data processing device based upon Fourier transformations or other parallel processing techniques, and the ways in which such techniques may be used to upgrade the performance of present and projected NASA systems were investigated. Activities toward this goal include; (1) production of near-diffraction-limited geodesic lenses in glass waveguides; (2) development of grinding and polishing techniques for the production of geodesic lenses in LiNbO3 waveguides; (3) development of a characterization technique for waveguide lenses; and (4) development of a theory for corrected aspheric geodesic lenses. A holographic subtraction system was devised which should be capable of rapid on-board preprocessing of a large number of parallel data channels. The principle involved is validated in three demonstrations.

Verber, C. M.↗