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Interactive recording and display device acts as very-high-speed data-input/output interface between analog (video) signals and standard digital-computer components. System can be used with various picture and memory sizes and can be controlled manually or by computer.
Tool detects noise sources by scanning sound "scene" and displaying relative location of noise-producing elements in area. System consists of ellipsoidal acoustic mirror and microphone and a display device.
An exact expression relating the coordinates of a point on the incident ray, a point of reflection from an arbitrary surface, and a point on the reflected ray is derived. The exact relation is then specialized for the case of grazing incidence, and first order and third order systematic analyses are carried out for a single reflective surface and then for a combination of two surfaces. The third order treatment yields a complete set of primary aberrations for single element and two element systems. The importance of a judicious choice for a coordinate system in showing field curvature to clearly be the predominant aberration for a two element system is discussed. The validity of the theory is verified through comparisons with the exact ray trace results for the case of the telescope.
A computer program was developed to generate random numbers on the Sigma V computer. A subroutine gave a random real number from a uniform distribution on the interval (0,1). A normal distribution with mean zero and variance 1 was also obtained.
The causes and effects of distortion in aircraft scanner data are reviewed and an approach to reduce distortions by modelling the effect of aircraft motion on the scanner scene is discussed. With the advent of advanced satellite borne scanner systems, the geometric and radiometric correction of aircraft scanner data has become increasingly important. Corrections are needed to reliably simulate observations obtained by such systems for purposes of evaluation. It is found that if sufficient navigational information is available, aircraft scanner coordinates may be related very precisely to planimetric ground coordinates. However, the potential for a multivalue remapping transformation (i.e., scan lines crossing each other), adds an inherent uncertainty, to any radiometric resampling scheme, which is dependent on the precise geometry of the scan and ground pattern.
An interfacing technique, zonation algorithms (ZONAL), which provides a means of utilizing LANDSAT information in a polygon-based geographic information system (GIS) is discussed. The ZONAL mechanisms are based on the use of existing GIS polynomial layer, thereby making the process entirely automated.
Details of the characteristics of the Uranian atmosphere and the surface features and projected formation processes of the Uranian moons are surveyed on the basis of 7000 images obtained by Voyager 2. Brightness distribution curves are provided for the CH4 Uranian atmosphere, and various anomalies, e.g., banding, that are apparent are discussed. Attention is given to the detectable cloud structure, circulation patterns and wind effects, noting that at certain latitudes the wind speeds exceed the planetary rotational velocity. The physical dimensions, orientations and compositions of the nine rings are described, along with the locations and sizes of the 10 shepherd satellites discovered between Miranda and Uranus. Finally, the large database accumulated on the visual characteristics of the five major satellites is examined in detail, particularly in relation to the orbits, origins, formation processes and surface features.
Payload space limitations, high optical fidelity and the desirability of fast slew rates imply that certain broadband active pointing systems should be lightweight, compact and high performance with small moments of inertia. This paper describes a 12 inch diameter, F/5 reflective hybrid with two fields of view in the visible SWIR, and one field of view in the LWIR region. By incorporating two classic optical designs, these stringent requirements are met at a level as to assure reasonably attainable weight, size and performance estimates.
The accuracy requirements of optical processors in adaptive optics systems are determined by estimating the required accuracy in a general optical linear algebra processor (OLAP) that results in a smaller average residual aberration than that achieved with a conventional electronic digital processor with some specific computation speed. Special attention is given to an error analysis of a general OLAP with regard to the residual aberration that is created in an adaptive mirror system by the inaccuracies of the processor, and to the effect of computational speed of an electronic processor on the correction. Results are presented on the ability of an OLAP to compete with a digital processor in various situations.
This paper presents an overview on the application of airborne video imagery (VI) for assessment of rangeland resources. Multispectral black-and-white video with visible/NIR sensitivity; color-IR, normal color, and black-and-white MIR; and thermal IR video have been used to detect or distinguish among many rangeland and other natural resource variables such as heavy grazing, drought-stressed grass, phytomass levels, burned areas, soil salinity, plant communities and species, and gopher and ant mounds. The digitization and computer processing of VI have also been demonstrated. VI does not have the detailed resolution of film, but these results have shown that it has considerable potential as an applied remote sensing tool for rangeland management. In the future, spaceborne VI may provide additional data for monitoring and management of rangelands.
The specifications and techniques related to the development of the NASA Spaceflight Optical Disk Recorder (SODR) are presented. The system is being developed for the temporary storage of high-resolution sensor data that will be collected at high data rates by future space programs. Typical spaceflight recording requirements are given for the Space Station Freedom, the Earth Observing System, and some planetary missions. SODR module characteristics are listed, emphasizing the two independent optical disk recorders and the random access to 5 gigabytes of data on each side of the disks. The modular design includes two I/O ports providing 150 Mbits/sec user data rate each, and multimodule reconfigurable architecture permitting the synchronization of up to 16 modules with a maximum data rate of 4.8 gigabits/sec.
Implementing a new experimental aerodynamic technique, a long electrically heated wire was placed across flows with general velocity distributions (wakes, jets). By measuring the temperature distribution along the wire with an IR camera, the flow behavior was identified. Furthermore, it is suggested that by using Nusselt number correlations, the velocity distributions can be deduced. Comparing the results with predictions based on heat transfer correlations, it was found that the IR camera cannot accurately track high gradient temperature fields. A correction procedure is outlined to account for the errors found in the measured results.
Eddy current probes have been used for many years for numerous sensing applications including crack detection in metals. However, these applications have traditionally used the eddy current effect in the form of a physically wound single or different probe pairs which of necessity must be made quite large compared to microelectronics dimensions. Also, the traditional wound probe can only take a point reading, although that point might include tens of individual cracks or crack arrays; thus, conventional eddy current probes are beset by two major problems: (1) no detailed information can be obtained about the crack or crack array; and (2) for applications such as quality assurance, a vast amount of time must be taken to scan a complete surface. Laboratory efforts have been made to fabricate linear arrays of single turn probes in a thick film format on a ceramic substrate as well as in a flexible cable format; however, such efforts inherently suffer from relatively large size requirements as well as sensitivity issues. Preliminary efforts to fully extend eddy current probing from a point or single dimensional level to a two dimensional micro-eddy current format on a silicon chip, which might overcome all of the above problems, are presented.
Under this grant the UC Berkeley PI, K. Hurley, joined the LOTIS collaboration. His task was to provide precise localization data on cosmic gamma-ray bursts, so that the LOTIS automated camera data could be searched more efficiently for evidence of optical emission from gamma-ray burst sources. This was accomplished. A program is now in place which automatically sends Interplanetary Network data on bursts via e-mail to H.S. Park, for every burst detected by the GRB experiment aboard the Ulysses spacecraft (for which K. Hurley is the P.I.). The data consist either of triangulation annuli (obtained when just two spacecraft observe the burst) or error boxes (when three widely separated spacecraft observe it). These define a locus of possible burst positions. The annuli intersect the large error circles of the CGRO-BATSE experiment, and reduce their areas by a factor of approximately 25 or more. The error boxes reduce the areas by factors of several hundred. This in turn reduces the area which must be searched for an optical counterpart. No such counterparts have been observed to date by the LOTIS experiment, but several interesting upper limits have been obtained.
Santa Barbara Remote Sensing (SBRS), Raytheon Company, is pleased to submit this quarterly progress report of the work performed in the third quarter of Year 2 of the Advanced THEMIS Project, July through September 2002. We review here progress in the proposed tasks. During July through September 2002 progress was made in two major tasks, Spectral Response Characterization and Flight Instrument Definition. Because of staffing problems and technical problems earlier in the program we have refocused the remaining time and budget on the key technical tasks. Current technical problems with a central piece of test equipment has lead us to request a 1 quarter extension to the period of performance. This request is being made through a separate letter independent of this report.
The complementary metal-oxide-semiconductor (CMOS) active pixel sensor (APS) technology has been developed over the past three years by NASA at the Jet Propulsion Laboratory, and has reached a level of performance comparable to CCDs with greatly increased functionality but at a very reduced power level.
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