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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.
161

Ground ice characteristics in permafrost on the Fosheim Peninsula, Ellesmere Island, N.W.T. : a study utilizing ground probing radar and geomorphological techniques

Barry, Peter January 1992 (has links)
No description available.
162

Moa and moa hunting : an archaeological analysis of big game hunting in New Zealand

Kooyman, Brian P, n/a January 1985 (has links)
This study is an archaeological examination of the prehistoric hunting of moa, a family (Dinornithidae) of now extinct large flightless birds that inhabited New Zealand. The analysis employs a detailed butchering pattern analysis for the moa remains and combines it with a lithic usewear microchipping and polish analysis. The usewear analysis examines two lithic materials, porcellanite and silcrete. The criteria used to distinguish worked material in the usewear study. The general patterns of moa exploitation and butchering are defined in a faunal analysis of moa remains from sites from throughout New Zealand. Hunting strategies are examined in a case study of the Clutha River area of southern New Zealand, by interpreting the results of the butchering pattern analysis in combination with the usewear analysis results and some of the general aspects of site type and location. It is concluded that moa were hunted by an individual hunting strategy, probably with wooden spears. Hunting was done from habitation sites, not from temporary camps established from base camps. Hunting did not specialise in any one particular moa species. In addition to meat, bone marrow was also particular moa species. In addition to meat, bone marrow was also extracted and eaten. No evidence of meat preservation was found. The results correspond well with expectations based on analogies from traditional hunting of other large birds and in east Polynesia, suggesting the methodology is reliable for studying hunting and could be applied elsewhere. The study also includes an examination of bone anatomical landmarks as a means to identifying moa species. The hypothesised significance of the variation in these traits is used to make suggestions about possible moa behaviour. It is suggested that Megalapteryx didinus was more awkward than the other moa, that Anomalopteryx didiformis may have had a diet more similar to that of the kiwi than to that of the other moa, and that Dinornis species may have balanced their centre of gravity differently from other moa. Based on the manner in which moa were hunted, it is proposed that moa did not congregate in large flocks.
163

Bathymetry and structure of San Clemente Island, California, and tectonic implications for the southern California continental borderland

Ridlon, James Barr 24 November 1968 (has links)
Five lithologic units, ranging in age from Middle Miocene to Recent, are defined on the basis of continuous seismic reflection profile records. Two of the units are Miocene sedimentary and volcanic rocks that have been truncated to form a major unconformity (post-orogenic surface) related to the most recent major tectonism of the region. The remaining units are post-orogenic unconsolidated sediments. The fault pattern offshore is generally related to that exhibited on the island. The pattern conforms to a wrench-fault system hypothesized by Moody and Hill (1956) modified by a general north-south tensional fracturing. The San Clemente Fault is assumed to be the primary wrench fault of the system. Anomalies in the thicknesses and the structure of the unconsolidated sediment and rock units tend to confirm the structural model. A canyon (Eel Ridge Canyon) off the west side of San Clemente Island appears to have been caused by pivotal faulting and erosion, and represents a boundary between different structural trends north and south. A prominent terrace around the island is postulated to have been wave-cut during and since the Late Pleistocene. The island has been tilted slightly to the west by Recent tectonism. A steep magnetic gradient off the east side of the island is considered the consequence of faulted volcanic flows comprising the island itself and a deep basic rock mass responsible for a large positive magnetic anomaly off the northwest side. Other magnetic anomalies reflect major structural trends. Earthquake epicenter data suggest a recent and possibly cyclical occurrence of fault activity in the northern Continental Borderland region and the study area. Fault offsets at the sea floor and earthquake epicenters along the San Clemente fault zone imply recent adjustments along the fault. Wrench-fault movement resulting from a simple shear or shear couple is considered to have caused the zone of brecciation along the San Clemente Fault and produced the fault-trace curvature so evident in a series of en echelon, northwest-striking major faults of the Borderland. Tensile release during periods of wrench-fault development has been a fundamental factor in the structural development of the Borderland basins. The entire structure of the Continental Borderland is believed to have developed by right-lateral movement along the series of wrench faults. These faults are believed to have resulted from a translation of force by sea-floor spreading originating on the East Pacific Rise in the Gulf of California region. This force is considered to have moved a northern Continental Borderland crustal plate westward by east to west release along major wrench faults bordering the north and south ends of this plate. Sediments, transported along channels developed along faults in the island block, were deposited in basins developed by faulting and folding of the pre-orogenic rocks. Transportation appears to have been by means of turbidity-current flows, sand flows, and slides. A maximum average depositional rate of 35 to 47 centimeters per 1,000 years is estimated for post-orogenic sediments. The following findings are suggested for inclusion in the Neogene history of the island: (1) the top 365 meters of Miocene andesitic lavas were deposited above sea level and tend to become slightly more basic in composition with depth; (2) subsidence of the island region and temporary sea-level stand(s) occurred after the deposition of the volcanic rocks, with possible periods of foundering to about the Late Pliocene; (3) emergence, lengthy subaerial exposure, and a period of partial submergence took place from about Late Pliocene through Early Pleistocene; (4) a north-south compressive force developed or recurred across the Borderland during Late Pliocene, developing the present northwest-southeast and east-west wrench-fault systems that have been intermittently active to the present time; (5) much of the present Borderland topography formed during the Pleistocene to Recent. / Graduation date: 1969
164

The classification and structure of marine macrobenthic assemblages at Arthur Harbor, Anvers Island, Antarctica

Richardson, M. D. (Michael D.) 21 July 1976 (has links)
In January-February 1971 five replicate 0.07 m² Van Veen grabs were obtained from each of 12 stations in Arthur Harbor and nine Van Veen grabs were obtained from two stations in nearby Bismark Strait. The 69 grab samples yielded 78,395 individuals which were separated into 282 taxa, including 108 species of annelids (54.5% of the individuals), 117 species of arthropods (30.3%), 35 species of molluscs (11.3%) and 22 species in other phyla (4.0%). The density of macrofauna (17,522 individuals/m²) found in Arthur Harbor was high compared to other reported areas. This high density was considered to be the result of high organic input from phytoplankton, phytobenthos and attached macroalgae, the efficient utilization of organic matter by macrobenthos and the slow growth rate of macrobenthic species as an indirect result of cold temperatures. Diversity values were moderately high with high species richness values and low evenness values. The high species richness values may be the consequence of seasonal constancy of temperature and salinity in Arthur Harbor, while low evenness values probably result from the physical stress of iceberg grounding coupled with high organic input. Six macrobenthic assemblages (site groups) and 11 species groups were found in the study area by classification analysis (Bray-Curtis dissimilarity, group-average sorting). Station groups were described by dominant species, density and diversity. Species groups were described by the dominance, fidelity, constancy, and percent abundance of constituent species restricted to site groups. The existence of discrete assemblages derived from the classification analysis was supported by direct ordination. Assemblages were interpreted to be areas of relative homogeneity which interrupt a general continuum of distribution of species with depth. The depth gradient probably represents several factors including increased constancy of temperature and salinity, lower organic input from attached macroalgae and phytobenthos, and a reduced incidence of iceberg grounding. Diversity, species richness, and evenness values increased with the depth gradient, while density values decreased with depth. The dominant species obtained in this study are widely distributed throughout the Antarctic, and 4% of the 162 taxa identified to species were also found at Terre Adelie, East Antarctica. Thus assemblages found in Arthur Harbor are probably circumpolar. In spite of the stability of temperature and salinity, Arthur Harbor macrobenthic assemblages were moderately stressed by glacial activity Icebergs, which often ground in Arthur Harbor, destroyed the benthos by crushing and churning the sediment. The disturbed area was first repopulated by motile, opportunistic species. These species fed on macroalgae which collected in the depression left by the iceberg. Scavengers and carnivores appeared later to feed on the grazers and macrofauna destroyed by iceberg grounding. Within a year the depression filled, and typical meiobenthic assemblages were re-established. Several years may be required before macrobenthic assemblages are re-established. Station 8, located near the glacial face had the lowest values of diversity, species richness, evenness, and density of any station in Arthur Harbor. These low values resulted from physical stress of glacial calving. Large pieces of ice calved from the glacial face and crushed the sediment by impact with the bottom. The waves created by impact of the calved ice with the water also disturbed the sediment creating an unstable sediment surface. / Graduation date: 1977
165

Comparison of actinobacterial diversity in Marion Island terrestrial habitats.

Sanyika, Walter Tendai. January 2008 (has links)
<p>The major aim of this study is to determine and compare the distribution of bacteria and actinobacteria in Marion Island terrestrial habitats.</p>
166

The Impacts of Green Spaces on Temperature Variability

Das, Smriti 07 December 2011 (has links)
Parks located in urban areas are known to mitigate the Urban Heat Island. Their cooling effects are well established in the literature as studies have been performed in urbanized areas around the world. This particular study was aimed at assessing the nature of suburban parklands in the City of Toronto vs. urban (downtown) and rural (outside the Greater Toronto Area) settings. To do this, five study sites were chosen; three parks of varying sizes (large, medium and small) and two backyards. The main research objective was to quantify the cooling effects; among the sizes, within the surrounding neighbourhood and through the day. The metrics used in this study included Day to Day Temperature Variability, Diurnal Temperature Range, and Temperature Variation through Time. The results showed the importance of trees in providing shade and the lake breeze from Lake Ontario. A clear suburban signal from the metrics was found.
167

The Impacts of Green Spaces on Temperature Variability

Das, Smriti 07 December 2011 (has links)
Parks located in urban areas are known to mitigate the Urban Heat Island. Their cooling effects are well established in the literature as studies have been performed in urbanized areas around the world. This particular study was aimed at assessing the nature of suburban parklands in the City of Toronto vs. urban (downtown) and rural (outside the Greater Toronto Area) settings. To do this, five study sites were chosen; three parks of varying sizes (large, medium and small) and two backyards. The main research objective was to quantify the cooling effects; among the sizes, within the surrounding neighbourhood and through the day. The metrics used in this study included Day to Day Temperature Variability, Diurnal Temperature Range, and Temperature Variation through Time. The results showed the importance of trees in providing shade and the lake breeze from Lake Ontario. A clear suburban signal from the metrics was found.
168

Vulkaners betydelse för utvinning av geotermisk energi, Krafla och Hengill, Island

Bergström, Sofia, Sjödin, Sophia January 2013 (has links)
Island har perfekta förutsättningar för att utvinna geotermisk energi. Det är beläget på den mittatlantiskaryggen mellan två aktiva plattor som interagerar med den hotspot som ligger under Island. Formandet av jordskorpan i området är komplex, hotspoten och manteln produce- rar tillsammans stora mängder magma som har gjort att jordskorpan har blivit mer mäktig oceanskorpan. Dessa parametrar gör Island till ett land med unika dynamiska system som ger de bästa förutsättning- arna för att kunna utvinna samt förse sin befolkning med geotermisk energi.  I denna studie är det främst två vulkaner som undersöks, Krafla och Hengill som ligger på norra respektive sydvästra Island. Vid dessa platser har man tagit flera borrprover där man fått reda på sammansättningen av magman. Sammansättningen har gjort det möjligt att utföra flera olika teoretiska modeller för att ta reda på mag- makamrars betydelse för energiutvinning. Syftet med detta projekt är att ta reda på temperaturerna i magmakamrarna och vid vilket djup dessa ligger på. Detta görs för att få reda på värmekällans egenskaper som då också hör ihop med ener- giutvinning. Här undersöks också hydrologiska flödesriktningar från de båda vulkanerna till deras geotermiska anläggningar i samma område. Utifrån magmans sammansättning tillämpades en modell i Excel för få fram djupet ner magmakamrarna för båda vulkanerna. Den hydrologiska 2D-modellen gjordes i programmet Hydrotherm som utvecklades av U.S Geological Survey där främst två ekvationer användes, Darcy’s lag samt ekvationen för termisk energitransport. Den sista modellen visade värmeflödet i de båda vulkanerna.  Resultatet visar att Hengill har en magmakammare vid djup på 0,735 km och att medeltemperaturen är 1227°C. Vid Krafla ligger magmakammaren på ett djup av 15 km och medeltemperaturen är 1161°C. Värmeflödet är nästan 3 gånger större vid Hengill än vid Krafla och flödesriktingen av värmen upp mot ytan skiljde sig mellan de båda vulkanerna. Vid Krafla stiger värmen nästan helt vertikalt mot ytan men vid Hengill kan man istället se att värmeflödet visar en mer utåtriktad böjd rörelse mot ytan. Den här typen av information är det som avgör vart man placerar de planerade kraftverken för maximal utvinning.
169

The research about "On This Island" of Benjamin Britten

Hsu, Chiung-Wen 28 June 2004 (has links)
Benjamin Britten was one of the major twentieth-Century composers in England, wrote twelve song cycles for voice and piano or various instruments, and the most prolific composer of the genre since Gustav Mahler. On this Island written during his early period, Britten employs various Baroque musical traits and the modern music techniques, which shows his influence on the neoclassical style. The study of the lecture recital document contains four main sections: the life of the composer, the stylistic features of Britten¡¦s song compositions, the written background of the cycle, and detailed analysis of the whole cycle. On This Island was Britten¡¦s first song cycle written for solo voice and piano. The success of premiere of the cycle brought him as one of the most important composer of this genre in the history of the twentieth-century music.
170

Quaestiones coae mythologae ...

Dibbelt, Hermann, January 1891 (has links)
Inaug.-diss.--Greifswald. / Vita. Includes bibliographical references.

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