4,235 research outputs found

    LANDSAT 4 investigations of Thematic Mapper and Multispectral Scanner applications

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    Interband detector noise was suppressed in the TIPS TM North Dakota data by median filtering. Procedures were developed to optimize the visual information content of thematic mapper data and evaluate the resulting photographic products by visual interpretation. A digital to analog TM transfer function was developed which properly placed the digital values on the most useable portion of film response curve. Utilizing the calculated minimum, mean, and maximum and the respective standard deviations of the bands from 50 sample scenes of TM data, look up tables were designed which resulted in acceptable photographic products. These products were evaluated by generation of color composites of selected band combinations using standard photo production procedures, and visual interpretation of scene features

    Testing Multiband and Multidate Photography for Crop Identification

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    Procedures used and results derived in a series of prerequisite interpretation tests that were performed on multiband and multidate photography are described. The results of these quantitative tests led to the selection of what was considered to be the best combination of multiband and multidate photographs for use in the Maricopa County Survey

    LANDSAT 4 investigation of thematic mapper and multispectral scanner applications

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    Six different band combinations of TM data were selected for evaluation by four experienced photointerpreters who were asked to rank the band combinations according to the ease with which the category of image feature designated for each set of combinations could be distinguished. There were four sets of combinations selected for each category of image feature. Scenes of Oklahoma City, Oklahoma and of the Sacramento Valley, California area were enlarged to 1:250,000 and 2 cm circular chips were cut from each print. A nonparametric rank order test was carried out on the data to determine if the interpreters found no difference among the band combinations in ranking for the designated categories. Kendall's coefficient of concordance (W) was calculated and the significance of the W value was determined by a chi-square test. A table summarizes the results of the evaluation and shows the rank order of band combinations indicated as valid by rejection of the null hypothesis

    LANDSAT 4 investigations of thematic mapper and multispectral scanner applications

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    Digital data analyses suggest the potential for TM data to provide improved land cover information with the mid-IR band being especially useful. Coefficients of variations for major land categories were greater for MSS data channels than for TM channels. Interpretation of black and white images of the six reflective TM bands indicates a strong interpreter preference for bands 5 and 7 for making distinctions in most of the classification categories that were addressed; however, a strong case can be made for a color composite containing visible, near-IR, and mid-IR spectral regions when distinguishing vegetation. A transformation from each red, green, blue color space into hue, intensity, and saturation space has potential for enhanced interpretability of TM color composite images. A perspective view transformation was demonstrated that could be useful for presently registered layers of spatial data in an oblique view format

    Testing the usefulness of ERTS-1 imagery for inventorying wildland resources in northern California

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    The usefulness of ERTS-1 imagery for inventorying wildland resources in northern California is discussed. Studies are being conducted in two large wildland areas, namely, the Feather River Watershed and the Northern Coastal Zone. The 2.5 million-acre Feather River headwaters area in northern California is the keystone watershed for the California Water Project, one of the most extensive and ambitious water resource developments ever attempted. Consequently, accurate and timely information on the quantity, quality and distribution of timber, forage, water and recreational resources is of immediate importance to each public agency and private group managing this vast, but inaccessible, wildland area. The Northern Coastal Zone (consisting of the counties of Marin, Sonoma, Mendicino, Humbolt and Del Norte) is relatively rural, with an economy based on agriculture, timber, commercial fishing and tourism. However, it is expected that intensive resource use resulting from increasing population will soon become a serious problem unless wise land use planning is undertaken. Thus, this coastal region is particularly well suited to investigations of the ways in which ERTS-1 imagery and other supporting data may be used in conducting land use evaluations

    Investigating Dispersal Ability to Infer Diversification in the Birds of Madagascar

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    The objective of this study was to investigate whether dispersal ability, as measured by a proxy of hand-wing index 2, influenced diversification of the birds of Madagascar at two scales. Madagascar is home to several avian lineages that have diversified greatly while other lineages are only represented by a single species. a key question in evolutionary biology is why some of these lineages diversified while others did not. One way to address this is to examine what features of these lineages promotes their diversification. Recent studies have focused on the relative importance of dispersal ability to diversification at the continental and island scales. to further test this relationship, I investigated whether dispersal ability, as measured by hand-wing index 2, influenced diversification in the birds of Madagascar at a large regional scale and smaller local scale within Madagascar. to assess whether dispersal ability influenced diversification of the birds of Madagascar I compared hand-wing index 2 of Malagasy and source (closest non-Malagasy relatives) clades of five radiating and three non-radiating lineages. I treated each lineage as an independent case study in the hopes of identifying a pattern reflecting a shift in dispersal ability upon colonization of Madagascar in radiating lineages. at a smaller local scale of macrohabitats within Madagascar, I examined whether variation in dispersal ability (HWI2) within widespread Malagasy species differed between subspecies restricted to macrohabitats reflecting local adaptation and divergence across macrohabitats. My study found that Malagasy species did not shift in their dispersal ability after colonizing Madagascar and thus, dispersal ability is not critical to the diversification of Malagasy endemics from their source clade in radiating or non-radiating lineages. However, at a smaller local scale of macrohabitats, I found variation in dispersal ability was likely due to local adaptations to macrohabitats. This study adds to our knowledge of dispersal ability and diversification patterns in Malagasy avifauna. This is a leading step towards additional studies to investigate the impact of potential geographic barriers to dispersal ability in the birds of Madagascar and could provide further insights into diversification patterns

    Quantitative evaluation of multiband photographic techniques Final report

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    Quantitative evaluation of multiband photographic techniques using combination of black and white and color photo

    Effect of Prices, Traits and Market Structure on Corn Seeding Density

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    Recent agronomic research finds that economically optimal seeding densities have likely increased for many Midwestern corn farmers as a result of genetic improvements including new GM traits such as Bt corn and herbicide tolerance. We derive a per acre demand model for hybrid seed corn to examine the determinants of corn seeding densities and estimate the model using a large data set of individual farmer seed corn purchases. Current results identify factors other than prices affecting farmer corn seeding densities. Among these factors are the GM trait of the seed corn, measures of the local seed corn market structure, seed purchase source and intended end use. We interpret these effects in terms of information effects—farmers with more/better access to the latest agronomic research indicating that recommended seeding densities should be increased tend to plant corn at higher densities.hybrid seed corn, Bt corn, herbicide tolerance, Herfindahl index, corn borer, rootworm, hyperbolic yield model, Agribusiness, Crop Production/Industries, Farm Management, Industrial Organization, Production Economics, D2, D21, Q1, Q12,

    LANDSAT 4 investigations of thematic mapper and multispectral scanner applications

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    Initial data screening, data handling and program testing were completed on the four-band Detroit scene and the seven-band northeast Arkansas scene. Data were received in early December for one primary eastern test site (Washington, D.C.) and one secondary eastern test site (Allegheny National Forest). A comprehensive digital data base was built for a portion of the Black Hills test site and is composed of historic LANDSAT MSS data; elevation, slope, and aspect data; land cover data; geologic data; thematic mapper simulator data; and digitized high altitude aircraft data. The thematic mapper and multispectral scanner data of the Washington area were resampled at 25 and 50 meters respectively, with map projection to UTM grid
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