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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.

Migration and natural disasters| Role of tornadoes and quality of life in internal migration patterns in tornado hot spots of the United States

Wei, Caiping 01 October 2014 (has links)
<p> Tornadoes are one of the most frequent and destructive disasters in the United States. Like other environmental calamities, tornadoes too act as push factors for migration. The objectives of this study are to define tornado hot spots in the US, to analyze migration effectiveness in the tornado hot spots and non-hot spots, and to explore how tornado and other socio-economic factors influence migration decision. Both quantitative and qualitative methods were used. Internal revenue service migration data, SPC tornado data, and Census Bureau data were used in the study. The results indicate that there are significant differences between migration patterns in the tornado hot spots and rest of the country: tornado hot spots are losing population to other regions. The results also indicated that along with the traditional socio-economic push and pull factors of migration, tornado occurrences also influenced people's migration decision in the United States.</p>

Local geodetic networks adjustments in three dimensions

Shrestha, Ramesh Lal. January 1983 (has links)
Thesis (Ph. D.)--University of Wisconsin--Madison, 1983. / Typescript. Vita. eContent provider-neutral record in process. Description based on print version record. Includes bibliographical references (leaves 252-258).

Computer software to calculate the systematic coordinate differences between two geodetic datums /

Besecky, Edward Joseph, January 1990 (has links)
Project report (M. Eng.)--Virginia Polytechnic Institute and State University, 1990. / Vita. Abstract. Includes bibliographical references (leaf 37). Also available via the Internet.

Effects of correlated distance observations on the strength of a horizontal geodetic network /

Malla, Rajendra Prakash. January 1978 (has links)
Thesis (M.S.)--Ohio State University. / Bibliography: leaves 140-141.

Magmatic-hydrothermal systems and associated magnetite-apatite-actinolite deposits, Echo Bay, Northwest Territories.

Reardon, Nancy Catherine. January 1992 (has links)
Magnetite-apatite-actinolite deposits occur as pervasive replacement, veins, pods and breccias within wall rocks to the plutons of the Mystery Island intrusive suite at Echo Bay, Northwest Territories. The plutons and their altered wall rocks host previously-mined pitchblende, native Ag, Ni-Co arsenide veins. Although numerous studies were carried out on the pitchblende, native Ag, Ni-Co arsenide veins, the origin of the altered rocks which host them remains uncertain. Overall, this study reveals that the formation of magnetite-apatite-actinolite veins, pervasive replacement of rocks by albite and magnetite-apatite-actinolite, and hydrothermal brecciation by magmatic fluids is consistent with geologic and isotopic data. Thus, it is inferred that these deposits formed by replacement in a hydrothermal system dominated by magmatic fluids exsolved by cooling epizonal plutons of the Mystery Island intrusive suite. (Abstract shortened by UMI.)

Multifractal modelling and spatial analysis with GIS: Gold potential estimation in the Mitchell-Sulphurets area, northwestern British Columbia.

Cheng, Qiuming. January 1995 (has links)
In combination with statistical modelling and GIS-based (Geographic Information Systems) spatial analysis, fractal and multifractal theory can be used for various purposes in the geosciences. Two multifractal models have previously been developed. One of these is based on the fractal dimension spectrum f($\alpha$) and the other one on the codimension function C($\gamma$). It can be shown that these two multifractal models are identical if $\gamma\ >$ D-$\alpha$(0). For $\gamma $ D$\sb{\rm L}.$ Similar relations hold true for surface areas and volumes of fractal geometries in three-dimensional space. The multifractal model provides new types of functions for modelling the covariance and semivariogram in spatial statistics as well as a new type of second-order intensity function for two-dimensional point processes. These functions are used to describe the underlying spatial structure of Au mineral occurrences in the Iskut River map sheet and for three relatively well known data sets: (1) Cochran's example of the number of tree seedlings per foot along a 200 ft long bed, (2) De Wijs's example of zinc values from a sphalerite-quartz vein near Pulacayo in Bolivia, and (3) Gerrard's example of trees in Lansing Woods. A new version of the weights of evidence technique based on the box-counting method is proposed for integrating various nonfractal and fractal patterns in mineral potential mapping, and is demonstrated with a case study of Au potential estimation in the Iskut River map sheet. The ordinary weights of evidence method is used for geochemical anomaly separation in the Mitchell-Sulphurets mineral district and gives results similar to those obtained with the fractal element concentration-area method. As another nonfractal method of geochemical anomaly separation, a new spatial statistical approach based on U-statistics is proposed which uses a moving average with optimal window radius. This method is tested by computer simulation and for geochemical anomaly separation of Au and Au-associated elements in stream sediment samples from the Iskut River map sheet. (Abstract shortened by UMI.)

The Lesotho geodetic control network.

Matela, Motlotlo P. January 2001 (has links)
The Geodetic network of Lesotho as established by the Directorate of Overseas Surveys in the 1950's, has been known to have distortions of several meters in some areas. This network is still very much in use today. Several altcmpts were made to strengthen the DOS network. but these attempts were not used for a complete readjustment. The South African Control net, which completely surrounds Lesotho, has recently been readjusted so as to bring it into sympathy with the WGS reference system used by GPS. It has become urgent to similarly update the Lesotho control system, to enable economical use of GPS surveying methods. This thesis addresses the problems of updating the Lesotho control system and also of bringing existing data onto the updated systcm. This thesis first reviews the historical background of Lcsotho and that of its geodetic net work. Different sets of data were collected and common points in the compared sets selected for the analysis. The South African readjustment was chosen as the standard, because it is the most recent, derived with the support of the new zero-order South African control net. The data sets were fitted to the reference system using conformal transformations from first up to fourth order. These comparisons were used to detect outliers. They revealed systematic distortions in the older data. which could be largely eliminated in the fourth-order transformation. The opportunity to update control point co-ordinates also gave an opportunity to revisit the existing choice of using two map panels of the Gauss Conform projection. The distortions involved in using a single Gauss Conform panel and also the UTM projection were investigated. A companson or all the methods and the recommendations concludes the section. Software was developed for transforming existing survey data onto the recommended updated reference system. The height system used in Lesotho is also reviewed because it forms part of the control net. The focus is on heights in relation to gravity. because that bears on the relation of published orthometric heights. with GPS-derived ellipsoidal heights. This section is mostly a literature review, starting with the theory of heights and gravity, proceeding onto the applied corrections and then showing what relations have been found. / Thesis (M.Sc.Sur.)-University of Natal, Durban, 2001.

Motorsport performance analysis| A spatio-temporal approach

Strand, Stephen 03 March 2015 (has links)
<p> As data logging technologies advanced, a point was reached where amateur motorsport enthusiasts could now log their vehicle's data while competing in motorsport events. Many drivers take advantage of these new data logging technologies but lack options for analyzing the data during and after motorsport events beyond standard tables and two-dimensional graphs. This thesis investigated the use of GIS as a tool for analyzing data collected during a motorsport event through time geography approaches and three-dimensional geovisualization techniques. Data were collected from the vehicle to analyze the speed and handling of the car while heart rate data were collected from the driver to help understand the driver's emotional state while navigating the course. Analysis of the data showed that time geography visualizations in a three-dimensional environment could help drivers better understand the data that had been collected from their vehicles and themselves and use it to improve their future performances when driving in motorsport events.</p>

The need and prospects for a new height control of peninsular Malaysia /

Sahrum Ses. Unknown Date (has links)
Thesis (PhD)--University of South Australia, 1997

Über einige Methoden für die Ausgleichung grosser Dreiecksnetze mit praktischer Anwendung im südschwedischen Ausgleichungsgebiet der Baltischen Geodätischen Kommission.

Asplund, Lars Erik Gottfrid, January 1900 (has links)
Avhandling--Tekniska högskolan, Stockholm. / Stamped on cover: K.T.H. Avh. 43. Extra t.p., with thesis statement, inserted. "Literatur": p. [9]-10.

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