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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.
11

Influence of runout path material on rock and debris avalanche mobility : field evidence and analogue modelling : a thesis submitted in partial fulfilment of the requirements for the degree of Doctor of Philosophy in Geological Sciences/Hazard and Disaster Management, University of Canterbury, New Zealand /

Dufresne, Anja. January 2009 (has links)
Thesis (Ph. D.)--University of Canterbury, 2009. / Typescript (photocopy). Includes bibliographical references (p. 225-233, 251-267). Also available via the World Wide Web.
12

Recent periglacial debris flows from Mount Rainier, Washington /

Copeland, Elizabeth A. January 1900 (has links)
Thesis ()--Oregon State University, 2010. / Printout. Includes bibliographical references (leaves 102-109). Also available on the World Wide Web.
13

Use of woody debris as an amendment for reclamation after oil sands mining

Brown, Robyn L. Unknown Date
No description available.
14

Space debris : legal and policy implications

Baker, Howard A. January 1988 (has links)
No description available.
15

Legal and technical considerations of space debris

Hürl, Kay-Uwe. January 2000 (has links)
This thesis deals with the technical and legal measures presently available to combat space debris. Space debris is not as far out as it sounds. The issue is real and may become severe if no action is taken. / Focusing on existing legal instruments, this study shows their inadequacy in addressing space debris. As space debris was not considered an actual or a legal problem at the time of drafting, the provisions of international space law fail to provide solutions in certain areas. / Recommendations for the future are made. Considering the increase in outer space activities, solutions for the space debris threat are a necessity. Developing technology will only solve some of the problems as the amount of space debris proliferates in collisions of existing debris. Therefore, legal challenges will also be faced, some of which are discussed herein.
16

The mineralogy and chemistry of micrometeorites

Graham, Giles Andrew January 2000 (has links)
Prior to their retrieval from low Earth orbit (LEO), the individual solar cells that make up the 'V2' solar array panel from the Huhble Space Telescope (HST) were prone to hypervelocity (>5 km/s ) impact damage from micrometeoroids and space debris. The analysis of such passive collector surfaces allows sampling of micrometeoroids that have not undergone any terrestrial atmospheric alteration and better defines the population of space debris particles below the lmm size range. Herein a new approach has been taken to try and identify the nature atid origin of impact derived residues generated in the individual solar cells from the HST. A total of 25 solar cells were selected on the basis that they contained impact craters (100-1000?n diameter) rather than larger impact holes (1-3mm diameter), as preliminary studies indicated that they were more likely to retain impact residues. These were subsequently analysed using digitised hack-scattered electron imaging, coupled with digitised x-ray elemental mapping and micro-spot analysis to locate, identify and classify the residues. 29 impact craters were located on solar cells. In the analysis of the residues; 3 were identified residues as space debris in origin, 6 unclassified and 20 as micrometeoroid. The space debris derived residues were identified as remnants of a paint fragment, a stainless steel particle and a fragment of a printed circuit board. The micrometeoroid derived residues were sub-classified in terms of mineral chemistry, with apparent mafic- and phyllo- silicates being the dominant components, with minor iron-nickel metal and iron sulfides, suggesting a broadly chondritic origin. Fe-Ni rich residue was also identified that would appear to belong to a group of non-chondritic particles previously unrecognised. Possible refractory or Ca/Al rich inclusions from a primitive micrometeoroid were also observed as near intact Ca-rich fragments, the textures of the individual grains suggested that they were not merely terrestrial contamination. Laboratory impact studies, using a light-gas-gun to accelerate small fragments (125- 250?m) of known meteorite mineralogies up to 5km/s, and then impact them into solar cells have generated a suite of residues that are analogues of those observed from LEO studies. The silicate minerals generated residues that were intimately associated with the host melt glass. Metallic sulfides and metals generated surface and sub-surface immiscible droplets. Several craters also contained near-intact fragments of minerals. Overall. despite the small sample set examined. the observed dominance of micrometeoroid to space debris residue chemistry (correlating to particle size range of 8-80 ?m) corresponds well to the accepted flux models.
17

Use of woody debris as an amendment for reclamation after oil sands mining

Brown, Robyn L. 06 1900 (has links)
This research determined if woody debris amendments facilitate land reclamation after oil sands mining. Specifically, it assessed if woody debris affects vegetation cover and richness, woody species survival and abundance, soil nutrients, temperature and water, microbial biomass carbon and mycorrhizal biomass. A four year old site and a two year old site were used to compare treatments with and without woody debris. Woody debris did not affect initial vegetation emergence, but increased species richness and decreased introduced species cover. After winter assessments found woody debris cover positively associated with vegetation cover. More saplings planted on woody debris treatments survived and woody debris cover was positively associated with woody plant abundance. Woody debris treatments had lower soil nitrogen and higher phosphorus, suggesting nitrogen immobilization and leachate high in phosphorus. Soil under woody debris had a lower temperature range and higher soil volumetric water content. No differences were found in microbial parameters. / Land Reclamation and Remediation
18

Geomorphology of debris flows and alluvial fans in Grand Canyon National Park and their influence on the Colorado River below Glen Canyon Dam, Arizona

Melis, Theodore S. January 1997 (has links) (PDF)
Thesis (Ph. D.)--University of Arizona, 1997. / Includes bibliographical references.
19

Delineating debris-flow hazards on alluvial fans in the Coromandel and Kaimai regions, New Zealand, using GIS : a thesis submitted in partial fulfilment of the requirements for the degree of Master of Science in Environmental Science at the University of Canterbury /

Welsh, Andrew J. January 2007 (has links)
Thesis (M. Sc.)--University of Canterbury, 2007. / Typescript (photocopy). Includes bibliographical references (leaves 150-169). Also available via the World Wide Web.
20

Hypervelocity impact analysis of International Space Station Whipple and Enhanced Stuffed Whipple Shields /

Kalinski, Michael E. January 2004 (has links) (PDF)
Thesis (M.S. in Astronautical Engineering)--Naval Postgraduate School, Dec. 2004. / Thesis Advisor(s): Eric Christiansen, Terry R. McNelley. Includes bibliographical references (p. 275-276) Also available online.

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