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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
241

A new method to achieve lithic use-wear discrimination using laser scanning confocal microscopy

Unknown Date (has links)
My study sought to acquire quantitative data from the surface of lithic tools and use that data to discriminate tools used on different contact materials. An experimental archaeological wear production method was conceived, whereby I and several volunteers produced wear on chert, heat-treated chert, and obsidian flakes by using those flakes on several contact materials. The flakes were then analyzed using a laser scanning confocal microscope, which recorded three-dimensional surface data from each tool. The data was analyzed using cluster analysis to find the ideal combination of parameters which correctly discriminated the flakes based on use-wear data. After finding acceptable parameters which grouped flakes appropriately through cluster analysis, those groups were subjected to a discriminant analysis. Each analysis returned a p-value under .05, meaning that the clustering based on the parameters Sq and Sfd produced by the cluster analysis was not random, but indicative of these variables' ability to discriminate lithic use-wear. The major advantage of the approach developed in this study is that it can quantitatively discriminate use-wear produced by different contact materials on flakes with no a priori information at all. / by Elliott Farber. / Thesis (M.A.)--Florida Atlantic University, 2013. / Includes bibliography. / Mode of access: World Wide Web. / System requirements: Adobe Reader.
242

Assessing estimators of feral goat (Capra hircus) abundance

Tracey, John Paul, n/a January 2004 (has links)
(1) Reliable measures of population abundance are essential for managing wildlife effectively. Aerial surveys provide a rapid and efficient means of surveying large mammals and many techniques have been developed to adjust for the inability to count all animals within transects. The probability of detection varies according to a range of factors which are important to consider when estimating density. Standardised survey methods developed in flat country are not readily transferable to steep terrain due to safety, access and difficulties delineating transect widths. Other methods have logistic constraints and must adhere to various other assumptions. (2) Density estimators are seldom examined using actual population size, hence their ability to correct for true bias is unknown. Studies that compare techniques are difficult to interpret because of the uncertainty of adherence to their respective assumptions. Factors influencing detection probability, estimators that correct for bias, the validity of their assumptions and how these relate to true density are important considerations for selecting suitable methods. The aim of this study was to obtain accurate and reliable methods for estimating the density of feral goats by improving predictions of detection probability, investigating the assumptions of aerial surveys, and examining the accuracy of 15 density estimators by comparing with total counts of feral goats. (3) Group size, vegetation and observer were the most important factors influencing the probability of observing a group of goats during aerial surveys. However, different approaches to analysing these data influenced the significance of variables and the predicted probabilities. Goat colour, type of helicopter, site and rear observer experience in hours were also found to be significant (P<0.05) when using likelihood equations based on all animals in the population rather than only those in the sample. The slope of the terrain was also shown to significantly (P=0.014) affect the probability of detection. (4) Indices are commonly used in wildlife management for their simplicity and practicality, but their validity has been questioned because of variable probability of detection. Results of this study suggest aerial survey indices are useful in monitoring a range of medium-sized mammal species across space and time if differences in detection probability between species, group size, vegetation and observer are considered and their effects are standardised. (5) An assumption of most sampling regimes that is fundamental but rarely examined is that animals are not counted more than once. In this study the behavioural responses of feral goats to helicopters were investigated as a basis for estimating the probability that goats were recounted. No long-term consequences were evident in feral goat behaviour of responses to helicopters. However, helicopter surveys were found to alter the structure of 42% of groups observed, with 28% of groups merging with others and 14% splitting into separate groups. Therefore, group size estimated from the air should not be considered as biologically important, and when estimating density, researchers should also avoid using group sizes determined from independent ground observations to correct group sizes determined from aerial surveys. Goats were also more likely to flush further when helicopters were within 150 m, which is close to or within standard helicopter strip widths. Substantial movement occurred between transects and 21% of goats were estimated to be available for recounting in adjacent transects. (6) Different detection probabilities between groups of goats may be particularly relevant when using double-counting, where multiple observers are �capturing� and �recapturing� animals in the same instant. Many analyses test and adjust for this �unequal catchability� assumption in different ways, with the approaches of Huggins and Alho allowing prediction of unique probability values for a range of co-variates. The approach of Chao attempts to correct for skewed distributions in small samples. The Horvitz-Thompson approach provides a useful basis for estimating abundance (or density) when detection probability can be estimated and is known to vary between observations according to a range of independent variables, and also avoids errors associated with averaging group size. (7) After correcting for recounting, the Alho estimator applied to helicopter surveys was the most accurate (Bias = 0.02) and reliable of all techniques, which suggests that estimates were improved by taking into account unconditional detection probability and correcting individual observations according to their characteristics. The positive bias evident in the Chao (Bias = 0.28) and Petersen (Bias = 0.15) aerial survey estimators may have been a result of averaging detection probability across all observations. The inconsistency and inaccuracy of the ground-based area-count technique emphasises the importance of other assumptions in density estimation, such as representative sampling and availability bias. The accuracy of index-manipulation-index techniques was dependent on the indices used. Capture-recapture estimates using mustering showed slight negative bias (Bias = -0.08), which was likely a result of increased probability of re-capture (i.e. trap happy). Ground-based capture-resight estimates were labour intensive and positively biased (Bias = 0.13), likely due to underestimating the area sampled, or overestimating the number of unmarked individuals with each sample. (8) Helicopter survey using double-counting is recommended for estimating the density of feral goats in steep terrain. However, consideration of recounting under intensive sampling regimes and adjustments for the factors that influence unconditional detection probability is required.
243

APPLICATION OF GEOLOGIC INTERPRETATION TO HIGHWAY SUBGRADE AND SURFACING DESIGN PROCEDURE ON THE KAYCEE-BARNUM STATE SECONDARY HIGHWAY, JOHNSON COUNTY, WYOMING

Edwards, Larry John, 1940- January 1972 (has links)
No description available.
244

The influence of land cover/land use characteristics on shuttle radar topography mission (SRTM) elevation error case studies from Louisiana and Thailand /

LaLonde, Tara Louise. January 2008 (has links)
Thesis (M.S.)--Michigan State University. Dept. of Geography, 2008. / Title from PDF t.p. (Proquest, viewed on Aug. 10, 2009) Includes bibliographical references (p. 191-201). Also issued in print.
245

Geodetické práce v průběhu realizace nového stavebního objektu / Geodetic operations during realization of the new construction project

PROKŮPKOVÁ, Nikola January 2012 (has links)
The thesis is focused on description of all geodetic operations, which need to be done before, during and after realization of a new construction project. The goal of this thesis is charting and orientation of a new construction project and following completion of the documentation for bureau of construction and the land registry. The theoretical part is aimed on common geodetic operations, which are devided into five main colums - Surveying operations for preparations and design of the new buildings, surveying operations carried out during design and completion of buildings, surveying operations for documentation and operational functionality of the buildings, other surveying activities and operations in land registry for constructions. In the practical part, the operations carried out during documents completion are described. This documentation serves for registration of a new object into the land registry and is also needed for building permission and final approval from the bureau of construction.
246

Vybudování výukového výškového a polohového bodového pole. / Creating 3D training network.

ŠOUREK, Martin January 2009 (has links)
Graduation theses is called Creating 3D Training Network. The thesis is divided into two main parts. The first part is theoretical and speaks about the creating of new 3D network and its surveying. Considering thesis{\crq}s size the theory is worked up factual for needfulness of that thesis. The theoretical knowledge were extract from accessible literature. The other part is practical. At this part I described the methodology of single works along with used machines and summary of calculations and outcomes of surveying. Concrete records of calculations, topography of new created points, overview of new created training network etc. are parts of appendices. The practical knowledge were obtained from literature, my knowledge and above all from the conslutations with the graduation theses{\crq}s supervisor. Graduation theses is aimed to creating of new 3D training network intended for education of Geodesy 1 and Geodesy 2 of branch Land Adjustment and Real Estate Trade.
247

Geodetické činnosti při rekonstrukci povrchu dálnice D1 / Geodetic Works During Reconstruction of Highway D1

Gunár, Peter Unknown Date (has links)
The main goal of the diploma thesis is the description of geodetic and construction activities and work processes dealing with reconstruction of the D1 highway surface in the section Rosice – Brno. The thesis is focused within the sphere of engineering geodesy and address the issue of creation of point field, stake-out, control measurement and the measurement of real building execution documents. Used survey procedures are analyzed in the context of the standard deviation listed in the project documentation or ČSN. The geotetic documentation is compiled for the chosen measured data.
248

Design totální stanice / Design of total station

Rozehnalová, Magda January 2010 (has links)
This diploma thesis presents a design solution of a total station. The proposal is processed especially with regard to technical, ergonomic and aesthetic requirements. The main inovation of the proposal lies in a complex ergonomic and aesthetic solution that better reflects modern trends in the field of surveying technology. In comparison to current designs of the device, new proposal of the total station perfectly integrates certain parts of the device, such as a control panel. Since it is a relatively small device, it is important to design all details properly, especially the form and arrangement of controls. The thesis also suggests a number of alternative solutions to particular problems. The proposal of a total station is suitable for various types of work and methods of surveying.
249

Evaluation of archaeological survey techniques : a comparison of phase Ia methodology at Site 12Ma648

Draeger, Cathy L. January 2007 (has links)
Reconnaissance survey (Phase Ia) provides the backbone to archaeological field methodology. Archaeological sites are typically discovered through reconnaissance techniques, more often via pedestrian survey and shovel probe testing. There is a lack of a consensus in the archaeological community on whether or not these techniques are effective as reconnaissance methodology. The following thesis evaluates these techniques' relative effectiveness at finding and preliminarily evaluating archaeological sites, the main objectives of reconnaissance. This study compares actual and simulated surveys using both techniques on a multi-component site in a woodland setting as well as addressing the cost-effectiveness of these techniques when estimating the time needed to complete them. / Department of Anthropology
250

A study of plant growth in relation to topography in the Derbyshire dales

Pope, David John January 1973 (has links)
No description available.

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