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At least 181 records · Page 10

Low-cost data analysis systems for processing multispectral scanner data

A research-oriented data analysis system was developed which is used for evaluating complex remote sensor systems and for development of techniques for application of remotely sensed data. Some modular hardware components were developed which may be added to one's existing facilities to establish a low-cost data analysis system for processing multispectral scanner data. Software modules which are compatible with small general purpose digital computers process and analyze remote sensor data, and convert it to information needed by users. The software modules are written in FORTRAN IV language for ease of transfer to other computer systems. The basic hardware and software system requirements are defined for some low-cost data analysis systems consisting of an image display system, a small general purpose digital computer, and an output recording device. The hardware modules consist of: a LANDSAT MSS data reformatting program; a series of spectral pattern recognition programs required to generate surface classification maps and tabular information; programs to convert computer generated maps from image space to a geographically referenced base; programs to extract data and irregularly shaped areas and to produce thematic maps of the designated areas; and programs to tabulate acreages of selected classification categories. Some off-the-shelf, inexpensive digital image display systems are described.

Whitley, S. L.↗

International Symposium on Remote Sensing of Environment, 11th, University of Michigan, Ann Arbor, Mich., April 25-29, 1977, Proceedings. Volumes 1 & 2

Consideration is given to remote sensor development and sensor data analysis and interpretation, and to the following fields of application of remote sensors: geology and mineral resources, meteorology, agriculture, forestry and rangeland, ocean and coastal regions, and environmental quality. Attention is also given to economic and institutional issues and technology transfer in the field of remote sensing, to microwave remote sensing and to the current and future role of remote sensing in operational programs.

Source record↗

Literature review of the remote sensing of natural resources

Abstracts of 596 documents related to remote sensors or the remote sensing of natural resources by satellite, aircraft, or ground-based stations are presented. Topics covered include general theory, geology and hydrology, agriculture and forestry, marine sciences, urban land use, and instrumentation. Recent documents not yet cited in any of the seven information sources used for the compilation are summarized. An author/key word index is provided.

Fears, C. B.↗

Active Optical Remote Sensing Sensors and Instrumentation for NASA’s Future Earth and Space Science Measurements/Missions

STRIVES Entry: 20230013683, Abstract—Active optical (Laser/Lidar) measurement techniques are critical for the future National Aeronautics and Space Administration (NASA) Earth, Planetary Science, Exploration, and Aeronautics measurements. The latest science decadal surveys recommend several missions requiring active optical systems to meet the science measurement objectives and the aeronautics community continues to use Laser/Lidar technologies to meet the aeronautics measurement objectives. This presentation will provide an overview of NASA efforts in developing and maturing state-of-the-art advanced solid-state flight laser/lidar systems for airborne and space-borne remote sensing measurements. The presentation will also provide details of a strategic approach for active optical technologies and techniques to meet the NASA’s future Earth and Space Science measurements/missions needs and requirements for space-based applications.

NASA's Future↗

High-density Schottky barrier IRCCD sensors for remote sensing applications

It is pointed out that the ambitious goals envisaged for the next generation of space-borne sensors challenge the state-of-the-art in solid-state imaging technology. Studies are being conducted with the aim to provide focal plane array technology suitable for use in future Multispectral Linear Array (MLA) earth resource instruments. An important new technology for IR-image sensors involves the use of monolithic Schottky barrier infrared charge-coupled device arrays. This technology is suitable for earth sensing applications in which moderate quantum efficiency and intermediate operating temperatures are required. This IR sensor can be fabricated by using standard integrated circuit (IC) processing techniques, and it is possible to employ commercial IC grade silicon. For this reason, it is feasible to construct Schottky barrier area and line arrays with large numbers of elements and high-density designs. A Pd2Si Schottky barrier sensor for multispectral imaging in the 1 to 3.5 micron band is under development.

Elabd, H.↗

Earth resources experiments and results

One of the major objectives of the Skylab Program was to investigate the feasibility of addressing the techniques of resource management through the use of remote sensors from a space platform. To accomplish these investigations, a package of broad-spectrum remote sensors was devised to investigate the extent to which surface features could be interpreted for potential use in understanding and managing the earth's resources. This paper will describe the total system capability needed to accomplish the resource management task; and, for a few specific examples, indicate how the results of EREP will contribute to the on-going development of the total resources system.

Zarcaro, J. G.↗

Mapping of submerged vegetation using remote sensing technology

Techniques for mapping submerged sea grasses using aircraft supported remote sensors are described. The 21 channel solid state array spectroradiometer was successfully used as a remote sensor in the experiment in that the system operated without problem and obtained data. The environmental conditions of clear water, bright sandy bottom and monospecific vegetation (Thalassia) were ideal.

Savastano, K. J.↗

Remote measurement of water color

This paper contains a discussion of the requirements and approaches which can be taken in the development of techniques for the analysis of remote multispectral imagery of natural bodies of water. There are two general approaches which can be used in the analysis of multispectral water color data collected by aircraft or satellite remote sensors. With the theoretical modeling approach, optically important constituents of natural waters are mathematically related to the upwelling radiance spectrum received by the remote sensor. With the empirical approach, the relationships are determined empirically by comparing remote sensing data with surface truth data. There are several levels of mathematical sophistication which can be applied to both approaches. The two approaches are discussed in some detail and it is concluded that the two approaches are closely related and should be pursued simultaneously for maximum utilization of the laboratory and field measurement data which will be needed. A set of minimum surface truth measurement parameters and techniques is suggested.

Mccluney, W. R.↗

A summary of the test procedures and operational details of an ocean dumping pollution monitoring experiment conducted 7 October 1976

A remote sensor experiment was conducted at a sewage sludge dump site off the Delaware/Maryland coast. Two aircraft serving as remote sensor platforms flew over the dump site during a sludge dump. One aircraft carried a multispectral scanner and the other aircraft carried a rapid scanning spectrometer. Data from sea-truth stations were collected concurrent with overpasses of the aircraft. All sensors were operational and produced good digital data.

Hypes, W. D.↗

Review of Concepts and Applications for Multispectral/Hyperspectral Focal Plane Array (FPA) Technology

Multispectral, and ultimately hyperspectral, focal plane arrays (FPAs) represent the logical extension of two-color FPA technology, which has already shown its utility in military applications. Incorporating the spectral discrimination function directly in the FPA would offer the potential for orders-of-magnitude increase in remote sensor system performance. It would allow reduction or even elimination of optical components currently required to provide spectral discrimination in atmospheric remote sensors. The result would be smaller, simpler instruments with higher performance than exist today.

McAdoo, James A.↗

Advanced Sensors and Applications Study (ASAS)

The present EOD requirements for sensors in the space shuttle era are reported with emphasis on those applications which were deemed important enough to warrant separate sections. The application areas developed are: (1) agriculture; (2) atmospheric corrections; (3) cartography; (4) coastal studies; (5) forestry; (6) geology; (7) hydrology; (8) land use; (9) oceanography; and (10) soil moisture. For each application area. The following aspects were covered: (1) specific goals and techniques, (2) individual sensor requirements including types, bands, resolution, etc.; (3) definition of mission requirements, type orbits, coverages, etc.; and (4) discussion of anticipated problem areas and solutions. The remote sensors required for these application areas include; (1) camera systems; (2) multispectral scanners; (3) microwave scatterometers; (4) synthetic aperture radars; (5) microwave radiometers; and (6) vidicons. The emphasis in the remote sensor area was on the evaluation of present technology implications about future systems.

Chism, S. B.↗

Apparatus and Method for Measuring Air Temperature Ahead of an Aircraft for Controlling a Variable Inlet/Engine Assembly

The apparatus and method employ remote sensing to measure the air temperature a sufficient distance ahead of the aircraft to allow time for a variable inlet/engine assembly to be reconfigured in response to the measured temperature, to avoid inlet unstart and/or engine compressor stall. In one embodiment, the apparatus of the invention has a remote sensor for measuring at least one air temperature ahead of the vehicle and an inlet control system for varying the inlet. The remote sensor determines a change in temperature value using at least one temperature measurement and prior temperature measurements corresponding to the location of the aircraft. The control system uses the change in air temperature value to vary the inlet configuration to maintain the position of the shock wave during the arrival of the measured air in the inlet. In one embodiment, the method of the invention includes measuring at least one air temperature ahead of the vehicle, determining an air temperature at the vehicle from prior air temperature measurements, determining a change in temperature value using the air temperature at the vehicle and the at least one air temperature measurement ahead of the vehicle, and using the change in temperature value to-reposition the airflow inlet, to cause the shock wave to maintain substantially the same position within the inlet as the airflow temperature changes within the inlet.

Gary, Bruce L.↗

NASA participation in the 1980 Persistent Elevated Pollution Episode/Northeast Regional Oxidant Study (PEPE/NROS) Project: Operational aspects

A field experiment designed to further understand the formation and transport of visibility reducing aerosols and to characterize regional scale air masses and urban plumes is described. Measurements were made primarily in the Ohio River Valley region. The NASA participation included obtaining measurements for the determination of mixing layer height and ozone profiles by using airborne remote sensor systems such as the ultraviolet differential absorption lidar, the high spectral resolution lidar, and the laser absorption spectrometer. Other NASA systems included the microwave atmospheric remote sensor, tethered balloons, an in situ measurements aircraft, and several photometer/transmissiometer systems.

Maddrea, G. L., Jr.↗

Frequency band justifications for passive sensors, 1 to 10 GHz

Remote sensor systems operating in the microwave region of the frequency spectrum provide information unobtainable with basic imaging techniques such as photography, television, or multispectral imaging. The frequency allocation requirements for passive microwave sensors used in the earth exploration satellite and space research services are presented for: (1) agriculture, forestry, and range resources; (2) land use survey and mapping: (3) water resources; (4) weather and climate; (5) environmental quality; and (6) marine resources, estuarine and oceans. Because measurements are required simultaneously in multiple frequency bands to adequately determine values of some phenomena, the relationships between frequency bands are discussed. The various measurement accuracies, dynamic range, resolutions and frequency needs are examined. A band-by-band summary of requirements, unique aspects, and sharing analyses of the required frequency bands is included.

Source record↗

Evaluation of aircraft microwave data for locating zones for well stimulation and enhanced gas recovery

Imaging radar was evaluated as an adjunct to conventional petroleum exploration techniques, especially linear mapping. Linear features were mapped from several remote sensor data sources including stereo photography, enhanced LANDSAT imagery, SLAR radar imagery, enhanced SAR radar imagery, and SAR radar/LANDSAT combinations. Linear feature maps were compared with surface joint data, subsurface and geophysical data, and gas production in the Arkansas part of the Arkoma basin. The best LANDSAT enhanced product for linear detection was found to be a winter scene, band 7, uniform distribution stretch. Of the individual SAR data products, the VH (cross polarized) SAR radar mosaic provides for detection of most linears; however, none of the SAR enhancements is significantly better than the others. Radar/LANDSAT merges may provide better linear detection than a single sensor mapping mode, but because of operator variability, the results are inconclusive. Radar/LANDSAT combinations appear promising as an optimum linear mapping technique, if the advantages and disadvantages of each remote sensor are considered.

Macdonald, H.↗

Sediment measurement in estuarine and coastal areas

A survey of uses of estuarine and coastal areas is given. Problems associated with these uses are discussed, and data needs for intelligent management of these valuable areas are outlined. Suspended sediment measurements are seen to be one of the greatest needs. To help understand the complexity of the problem, a brief discussion of sediment mechanics is given, including sediment sources, characteristics, and transport. The impact of sediment mechanics on its direct measurement (sampling and analysis) is indicated, along with recommendations for directly obtaining representative data. Indirect measurement of suspended sediment by remote sensors is discussed both theoretically and in the light of some recent experiences. The need for an integrated, multidisciplinary program to solve the problem of quantitatively measuring suspended sediment with remote sensors is stressed, and several important considerations of such a program and benefits to be derived therefrom are briefly addressed.

Shelley, P. E.↗

A survey of laser and selected optical systems for remote measurement of pollutant gas concentrations

Applications of the Differential Absorption Lidar (DIAL) technique to the remote sensing of pollutant gases are surveyed. In the DIAl technique, the differential absorption of two laser beams reflected back to a receiver from a target determines the concentration of the gas being studied. The types of instruments available are considered in detail: dye lidar (to measure nitrogen dioxide, sulfur dioxide, and ozone); carbon dioxide laser (for ozone, ethylene, ammonia, and hydrazine), helium-neon laser (for methane); hydrogen fluoride laser (for HF); and tunable diode laser (for nitric oxide and carbon monoxide). DIAL instruments are compared with other optical remote sensors such as Fourier-transform infrared spectrometers, correlation spectrometers (COSPEC and GASPEC), and grating spectrometers; and criteria for the selection of an appropriate gas measuring system are suggested. Laser and other optical remote sensors are found to be cost effective in many cases, despite the fact that they are more costly than point-monitoring systems.

Grant, W. B.↗