On the identification of nonlinear dynamical systems
Independent noise driven nonlinear dynamic systems identification, performing linear discrete-time scalar measurements
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Independent noise driven nonlinear dynamic systems identification, performing linear discrete-time scalar measurements
Gradient search procedures application for nonlinear system unknown parameters identification from system dynamic response observations
Bright star at radio source and X ray observations evaluation from optical identification of Cygnus X-1, taking into account spectrum and energy distribution characteristics
Computerized bacterial identification system to process Apollo spacecraft sample laboratory test results in NASA Planetary Quarantine Lunar Information System
Iterative computer aided procedure was developed which provides for identification of boiler transfer functions using frequency response data. Method uses frequency response data to obtain satisfactory transfer function for both high and low vapor exit quality data.
Constructive recommendations are suggested for pollution problems from offshore energy resources industries on outer continental shelf. Technical management techniques for pollution identification and control offer possible applications to space engineering and management.
Important range-shrub species were identified at acceptable levels of accuracy on large-scale 70 mm color and color infrared aerial photographs. Identification of individual shrubs was significantly higher, however, on color infrared. Photoscales smaller than 1:2400 had limited value except for mature individuals of relatively tall species, and then only if crown margins did not overlap and sharp contrast was evident between the species and background. Larger scale photos were required for low-growing species in dense stands. The crown cover for individual species was estimated from the aerial photos either with a measuring magnifier or a projected-scale micrometer. These crown cover measurements provide techniques for earth-resource analyses when used in conjunction with space and high-altitude remotely procured photos.
A program has been written for the identification of parameters in certain linear systems. These systems appear in biomedical problems, particularly in compartmental models of pharmacokinetics. The method presented here assumes that some of the state variables are regularly modified by jump conditions. This simulates administration of drugs following some prescribed drug regime. Parameters are identified by a least-square fit of the linear differential system to a set of experimental observations. The method is especially suited when the interval of observation of the system is very long.
The agricultural and forestry areas which comprise the watershed of the Chesapeake Bay are described. Major problems of watershed creation and management with emphasis on the erosion problem are discussed. Remote sensing as it relates to the identification of plant species and vigor, pollution, disease, and insect infestation are examined. The application of infrared photography, multispectral sensing, and sequential survey is recommended to identify ecological changes and improve resources management.
This paper discusses the application of a generalized identification method for flight test data analysis. The method is based on the maximum likelihood (ML) criterion and includes output error and equation error methods as special cases. Both the linear and nonlinear models with and without process noise are considered. The flight test data from lateral maneuvers of HL-10 and M2/F3 lifting bodies are processed to determine the lateral stability and control derivatives, instrumentation accuracies and biases. A comparison is made between the results of the output error method and the generalized ML method for M2/F3 data containing gusts. It is shown that better fits to time histories are obtained by using the generalized ML method.
Laboratory spectra of the 3nu(sub 3) band of (C-13)H4 at 1.1 micron were analyzed along with high-resolution image-tube spectra of Jupiter in the appropriate spectral region. Comparison of several J-multiplets in these spectra resulted in the identification of (C-13)H4 in the atmosphere of Jupiter. A Jovian C-12/C-13 isotopic abundance ratio of 110 (plus or minus 35) has been derived from the equivalent width of the R(2) multiplet measured on the two best spectrograms.
The light scattering properties of single bacterial cells were examined as a possible means of identification. Three species were studied with streptococcus faecalis exhibiting a unique pattern; the light-scattering traces for staphylococcus aureus and escherichia coli were quite similar although differences existed. Based on preliminary investigations, the light scattering approach appeared promising with additional research needed to include a wide variety of bacterial species, computer capability to handle and analyze data, and expansion of light scattering theory to include bacterial cells.
Identification of irrigated winter wheat from ERTS-1 imagery for Finney County, Kansas
Crop identification using ERTS-1 imagery for southeastern South Dakota
Identification of large masses of citrus fruit and rice fields in Eastern Spain
Identification of agricultural crops in Dekalb, Ogle, and Lee counties in Illinois by computer processing of ERTS-1 MSS data
Identification and mapping of soils, vegetation, and water resources in Lynn County, Texas by computer analysis of ERTS-1 MSS data
Identification of coastal vegetation species in ERTS-1 imagery of Delaware Bay