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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.
1

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>
2

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.
3

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).
4

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.
5

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.)
6

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.)
7

Recovery of terrestrial water storage change from low-low satellite-to-satellite tracking

Chen, Yiqun 10 December 2007 (has links)
No description available.
8

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.
9

Measuring earth crustal deformations using GPS and geodetic data in relation to the Rion-Antirion bridge construction

Komninos, Anastasios A. January 2003 (has links)
No description available.
10

Tectonic and paleoelevation history of the Thakkhola Graben and implications for the evolution of the southern Tibetan Plateau

Garzione, Carmala Nina January 2000 (has links)
Sediment accumulation in extensional basins in the Tibetan Plateau records tectonic processes and paleoenvironments on the plateau. It is generally assumed that extension on the plateau took place during uplift of the plateau. Based on this assumption, several studies have been aimed at determining the timing of extensional basin development as a proxy for the timing of uplift of the plateau. This dissertation documents the sedimentology of the N-trending Thakkhola graben in the southern Tibetan Plateau in an attempt to test various models for the timing and mechanisms of uplift of the plateau. Magnetostratigraphic and stable carbon isotopic age constraints indicate that deposition in the Thakkhola graben occurred during the Late Miocene (∼11 Ma) to Pliocene. The oxygen isotopic composition of carbonate rocks deposited in the basin records the isotopic composition of paleometeoric water that fell in the basin and in flanking drainages when the carbonate was precipitating. Carbonate oxygen isotopes indicate high-elevation rainfall in the basin, consistent with modern elevations since the onset of deposition in the basin. This implies that the average elevation in the Thakkhola graben has been >4,500 m since it began to form. Lateral facies changes, conglomerate provenance, and paleocurrent data document significant displacement on the western basin-bounding fault since deposition began in the basin. By Pliocene time, a large, southward axial drainage had developed that was similar in size to the modern Kali Gandaki River, which drains the southern plateau, through the Thakkhola graben and Himalayan fold-thrust belt to the south. Change in environments of deposition in the Thakkhola graben indicates trends toward an increasingly arid climate through time. This climate change is documented throughout south Asia and possibly Tibet between ∼8 and 7 Ma and have been assumed to reflect uplift of the plateau. However, high elevation in the Thakkhola graben since ∼11 Ma challenges these commonly held notions.

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