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Remote aerial sensing and automatic mapping for forest resources information system
Zero sum differential game solution for aerial combat problem, applying direct gradient methods
A proposal is made for mapping from aerial photographs from the EROS program. Three kinds of maps (geomorphic or landform, soil, and surficial deposit) are being prepared at 1:250,000 scale for an 8000-square-mile area between Tucson and Ajo, Arizona. Nine cameras used on NASA mission 101 provided color, color infrared, and multispectral air photos from about 60,000 feet above the terrain and with photo scales ranging from 1:60,000 to 1:240,000. This area was selected because it provides a good sample of desert terrain and is suited for improving and testing the photointerpretive techniques for mapping geologic terrain features with small-scale photos.
Changes in the red tonal response of Kodak Ektrachrome Infrared Aero 8443 film (EIR) are often incorrectly attributed solely to variations in infrared light reflectance of plant leaves, when the primary influence is a difference in visible light reflectance induced by varying chlorophyll contents. Comparisons are made among aerial photographic images of high- and low-chlorophyll foliage. New growth, foot rot, and boron and chloride nutrient toxicites produce low-chlorophyll foliage, and EIR transparency images of light red or white compared with dark-red images of high-chlorophyll foliage. Deposits of the sooty mold fungus that subsists on the honeydew produced by brown soft scale insects, obscure the citrus leaves' green color. Infected trees appear as black images on EIR film transparencies compared with red images of healthy trees.
Two statistical models are compared in the classification of crops recorded on color aerial photographs. A theory of error ellipses is applied to the pattern recognition problem. An elliptical boundary condition classification model (EBC), useful for recognition of candidate patterns, evolves out of error ellipse theory. The EBC model is compared with the minimum distance to the mean (MDM) classification model in terms of pattern recognition ability. The pattern recognition results of both models are interpreted graphically using scatter diagrams to represent measurement space. Measurement space, for this report, is determined by optical density measurements collected from Kodak Ektachrome Infrared Aero Film 8443 (EIR). The EBC model is shown to be a significant improvement over the MDM model.
The feasibility of performing inventories of agricultural resources using very small scale aerial or space photography was studied. The results were encouraging on two counts: (1) The very practical problems of an operational survey are being faced and solutions are being found. (2) It seems that a fully operational agricultural inventory using space photography is not beyond the scope of present technology.
A program for determining the feasibility of deriving sea surface wind speeds by remotely sensing ocean surface radiances in the nonglitter regions is discussed. With a knowledge of the duration and geographical extent of the wind field, information about the conventional sea state may be derived. The use of optical techniques for determining sea state has obvious limitations. For example, such means can be used only in daylight and only when a clear path of sight is available between the sensor and the surface. However, sensors and vehicles capable of providing the data needed for such techniques are planned for the near future; therefore, a secondary or backup capability can be provided with little added effort. The information currently being sought regarding white water coverage is also of direct interest to those working with passive microwave systems, the study of energy transfer between winds and ocean currents, the aerial estimation of wind speeds, and many others.
Simulation and interpretation of aerial or orbital TV and photographic observations of earth geographic patterns
A system which simulates observation of the earth surface by aerial or orbiting television devices has been developed. By projecting color slides of photographs taken by aircraft and orbiting sensors upon a rear screen system, and altering scale of projected image, screen position, or TV camera position, it is possible to simulate alternatives of altitude, or optical systems. By altering scan line patterns in COHU 3200 series camera from 525 to 945 scan lines, it is possible to study implications of scan line resolution upon the detection and analysis of geographic patterns observed by orbiting TV systems.
Two clustering techniques were used for terrain mapping by computer of test sites in Yellowstone National Park. One test was made with multispectral scanner data using a composite technique which consists of (1) a strictly sequential statistical clustering which is a sequential variance analysis, and (2) a generalized K-means clustering. In this composite technique, the output of (1) is a first approximation of the cluster centers. This is the input to (2) which consists of steps to improve the determination of cluster centers by iterative procedures. Another test was made using the three emulsion layers of color-infrared aerial film as a three-band spectrometer. Relative film densities were analyzed using a simple clustering technique in three-color space. Important advantages of the clustering technique over conventional supervised computer programs are (1) human intervention, preparation time, and manipulation of data are reduced, (2) the computer map, gives unbiased indication of where best to select the reference ground control data, (3) use of easy to obtain inexpensive film, and (4) the geometric distortions can be easily rectified by simple standard photogrammetric techniques.
A method is presented which can be used to map silicate rock-type from aerial infrared data. The method has been partially tested over a sand quarry at Mill Creek, Oklahoma, in which highly siliceous targets were discriminated from nonsilicates in the scene. The technique is currently being tested experimentally on basic silicates. On the basis of the Mill Creek results and theoretical considerations, percent SiO2 differences as small as 14% should be detectable with the University of Michigan's currently available detectors.
Two statistical models are comapared in the classification of crops recorded on color aerial photographs. A theory of error ellipses is applied to the pattern recognition problem. An elliptical boundary condition classification model (EBC), useful for recognition of candidate patterns, evolves out of error ellipse theory. The EBC model is compared with the minimum distance to the mean (MDM) classification model in terms of pattern recognition ability. The pattern recognition results of both models are interpreted graphically using scatter diagrams to represent measurement space. Measurement space, for this report, is determined by optical density measurements collected from Kodak Ektachrome Infrared Aero Film 8443 (EIR). The EBC model is shown to be a significant improvement over the MDM model.
The feasibility of performing inventories of agricultural resources using very small scale aerial or space photography has been investigated. Results to date are encouraging on two counts: (1) the questions posed initially are being answered, and (2) it would seem that a fully operational agricultural inventory using very small scale photography is not beyond the scope of present technology. The biggest problems to be faced in establishing a functional inventory system are those concerning logistics and data handling.
Comparison of multispectral imagery and aerial surveys of Massachusetts bays
Artificial defoliation in corn was used to explore the usefulness of aerial photography in detecting crop insect infestations. Defoliation on the top of plants was easily detected, while that on the base was less so. Aero infrared film with Wratten 89B filter gave the best results, and morning flights at the scale of 1:15840 are recommended. Row direction, plant growth stage, and time elapse since defoliation were not important factors.
The use of aerial photography as a method for determining the wildlife conditions of an area is discussed. Color infrared photography is investigated as the most effective type of remote sensor. The characteristics of the remote sensing systems are described. Examples of the remote sensing operation and the method for reducing the data are presented.
The values employed to define the sound reduction coefficient of exterior walls for aerial noise do not take into account the continuous increase in the outside noise level nor its energy variation as a function of time. These aspects are analyzed by estimating the outside and inside noise levels on the basis of calculating an equivalent noise (L sub ech), a level with a maximum duration and the values of L sub 10, L sub 50 and L sub 90. The values obtained permit determination of the wall's sound reduction coefficients that are compared with those obtained by the customary method. It is shown that the sound reduction values of the wall coincide for the case of sound levels with a maximum duration and the values of L sub 90.
Satellite imagery and small-scale (1:120,000) infrared ektachrome aerial photography for the development of improved forest and land inventory techniques in the boreal forest region are presented to demonstrate spectral signatures and their application. The forest is predominately mixed, stands of white spruce and poplar, with some pure stands of black spruce, pine and large areas of poorly drained land with peat and sedge type muskegs. This work is part of coordinated program to evaluate ERTS imagery by the Canadian Forestry Service.