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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.
501

�Where land meets water� : rights to the foreshore of Otakou Maori Reserve

Hanham, Susan Janette, n/a January 1996 (has links)
Rights to possess and/or use the foreshore of New Zealand are not clear, and are even cloudier in relation to Maori freehold land that is on the coast. This thesis investigates the law pertaining to rights in the foreshore, and the facts pertaining specifically to the use of the Otakou Maori Reserve foreshore. In particular, the research question is this: what does aboriginal title mean in 1996 for Otago Maori? Examining the legal issues, searching individual titles and gathering oral history are the methods used to answer this question. First, the law. In New Zealand the Crown is prima facie the absolute owner of the foreshore. This can be displaced by proof to the contrary. The doctrine of aboriginal title recognises the legal continuity of tribal property rights upon the Crown�s acquisition of sovereignty over their territory. Aboriginal title can be divided into two categories - territorial and non-territorial. Territorial title represents a tribal claim to full ownership, and non-territorial title to rights that are less than absolute ownership, such as the right to cross land, to fish and to collect flora and fauna. It is this doctrine of aboriginal title as it relates to the foreshore that can displace the Crown�s absolute ownership of the foreshore. Second, the facts. 99% of the coastal land parcels of Otakou Maori Reserve are described in written documentation as to the line of mean high water. This 99% is made up 17% Maori freehold land, 49% general land and 33% vested in the Crown or the Dunedin City Council. The remaining 1% is Maori freehold land that does not have its boundary at mean high water, but has a fixed upland boundary. Oral history facts from the takatawhenua identify that the foreshore continues to be used for access, travel, and the collection of kai moana and sea resources. The findings reveal that Kai Tahu ki Otakou have never extinguised their territorial and non-territorial aboriginal title to the foreshore of Otakou Maori Reserve. Suggested areas for future research include an investigation of other Maori reserves in Otago, and examining the doctrine of aboriginal title as it relates to the beds of watercourses.
502

The effect of wave grouping on shoaling and breaking processes

Shand, Thomas Duncan, Civil & Environmental Engineering, Faculty of Engineering, UNSW January 2009 (has links)
Determining the largest breaking wave height which can occur in water of finite depth is a fundamental reference quantity for the design of coastal structures. Current design guidelines are based on investigations which predominantly used monochromatic waves, thereby neglecting group effects which are inherent to the free propagation of waves in deep water. The Coastal Engineering Manual (CEM) states that wave grouping and its consequences is of significant concern, with breakwater armour damage being generally attributed to higher waves associated with wave groups. However, the CEM also acknowledges that there is little guidance and few formulae for use in practical engineering. This thesis describes a laboratory-based investigation into the effect of wave groupiness on wave shoaling, breaking and surf zone processes. New optical-based techniques for data abstraction, developed within this study, have allowed examination of the interaction between deep water intra-wave group processes and shallow water shoaling processes. The applicability of existing methods for predicting breaking wave height and position is evaluated, along with the implications of groupiness on engineering design in the nearshore. The effect of wave groupiness on overtopping and hazard on emerged rock platforms is similarly assessed. Wave group testing has revealed that the spatial phasing of intra-group processes during shoaling can result in considerably different shoaling and breaking regimes. Under certain regimes, wave breaking occurred further shoreward and in a more plunging manner than under other regimes. Within the mid to inner surf zone, waves were also observed to propagate into shallower water before breaking than is predicted by existing design guidelines. This could result in under-prediction of wave height by up to 100%. Expressions are developed for the prediction of maximum wave heights and surface elevation on plane slopes. These expressions implicitly include non-linear group effects and group-induced water-level variations within the surf zone, and are found to provide conservative upper envelopes for the range of data observed within the current testing regimes. Predictive schemes are similarly developed for overtopping hazard on emerged rock platforms based on critical wave and water-level conditions. Variations in maximum overtopping flow values due to intra-wave group processes of up to +/-35% were found. These group effects were found to reduce by up to 30% the threshold wave conditions before the initiation of hazard.
503

The Hyde-Macraes shear zone in Otago: A result of continental extension or shortening? A kinematic analysis of the Footwall Fault

Butz, Christoph Florian January 2007 (has links)
Mineralised shear zones in Otago are often truncated by regional low-angle faults, which juxtapose schist of different metamorphic grade. The Footwall Fault and the Hyde-Macraes Shear Zone are one example for this kind of tectonic setting, and are the subject to this study. Although, the mechanisms for the development of the mineralised thrust-origin shear zones are well studied, the relationship to the truncating faults is still poorly understood. Currently, the truncating low-angle faults are assumed to be related to crustal extension, starting in the early Cretaceous after the schist passed the ductile-brittle transition. This study presents new kinematic data for the Footwall Fault, suggesting development of normal sense movement under ductile conditions due to an abundant shear band cleavage in the footwall, which dynamically recrystallises quartz grains. However, brittle high-angle normal faults truncating these shear bands indicate either reactivation of normal sense movement after passing the ductile-brittle transition or continuous normal sense movement during the transition. Furthermore, this study presents a model, which suggests a regional scale rolling hinge development, consisting of an array of individual low-angle normal faults along the boundary of the textural zone change from TZ IV to TZIII, and strike-parallel high-angle faults at the NE margin of the Otago schist.
504

Spatial and temporal distribution of a rhyolite compositional continuum from wet-oxidizing to dry-reducing types governed by lower-middle crustal P-T-ƒO₂-ƒH₂O conditions in the Taupo Volcanic Zone, New Zealand.

Deering, Chad D. January 2009 (has links)
A continuum of rhyolite compositions has been observed throughout the Taupo Volcanic Zone (TVZ) over the past 550 kyr. reflecting changes in the ƒH2O, ƒO₂, and P-T conditions in a lower crustal 'hot-zone' (10-30 km) where these evolved melts are generated by crystal fractionation of successively intruded basaltic magmas. The rhyolite compositional continuum is bound by two distinct end-member types: R1 is characterized by hydrous minerals (hornblende ± biotite), low FeO*/MgO (calc-alkaline series), low MREE, Y, and Zr, and high Sr; and R2 is characterized by anhydrous minerals (orthopyroxene ± clinopyroxene), high FeO*/MgO (tholeiitic series), high MREE, Y, and Zr, and low Sr. Slab-derived aqueous fluid components (Ba, Cl) correlate well with oxygen fugacity, and other well defined characteristics of silicic magmas in the Taupo Volcanic Zone (TVZ) between a cold-wet-oxidizing magma type (R1: amphibole ± biotite; high Sr, low Zr and FeO*/MgO, depleted MREE) and a hot-dry-reducing magma type (R2: orthopyroxene ± clinopyroxene; low Sr, high Zr, and FeO*/MgO, less depleted MREE). Oxygen fugacity was obtained from analysis of Fe-Ti oxides and ranges between -0.039 to +2.054 log units (ΔQFM; where QFM = quartz + fayalite + magnetite buffer) and is positively correlated with the bulk-rock Ba/La ratio, indicating that slab-derived fluid is the oxidizing agent in the rhyolites. Chlorine contents in hornblende also correlate with the bulk-rock Ba/La ratio. Hence, high fluid-flux typically correlates with the R1 and low fluid-flux with R2 rhyolite magma types. A geochemical evolution and distribution can be tracked in time and space throughout the central region of the TVZ from 550 ka to present and has revealed two distinct magmatic cycles that vary in length. The first cycle included widespread R1 type magmatism across the central TVZ beginning ca. 550 ka and was directly associated with previously unreported dome-building and ignimbrite-forming volcanism, and led to a voluminous (>3000 km³) ignimbrite 'flare-up' between ca. 340 and 240 ka. These magmas also display the highest K₂O and Pb isotopic compositions compared to those erupted more recently, and is consistent with a peak in slab-derived sediment input. The second cycle began roughly 180 ka, erupting ca. 800 km³ of magma, and continues to the present. The duration, rate, and composition of melt production within these cycles appears to be governed by the flux of fluid/sediment released from the subducting slab, while the distribution of melts may be governed more by extension along the central rift axis. The Matahina Ignimbrite (~160 km³ rhyolite magma; 330 ka) was deposited during a caldera-forming eruption from the Okataina Volcanic Centre, TVZ. The outflow sheet is distributed primarily from the northeast to southeast and consists of a basal plinian fall member and three ash-flow members. Pumice clasts are separated into three groups defined by differences in bulk geochemistry and mineral contents: high CaO, MgO, Fe₂O₃T, TiO₂, and low Al₂O₃, +hornblende (A2), low CaO, MgO, Fe2O3T, TiO2, ±hornblende (A1), and a subset to A1, which has high-K, +biotite (B). Two types of crystal-rich mafic clasts were also deposited during the final stages of the eruption. The distinct A and B rhyolite magma types are petrogenetically related to corresponding type A and B andesitic magma by up to 50% crystal fractionation under varying ƒO₂-ƒH₂O conditions. Further variations in the low- to high-silica rhyolites can be accounted for by up to 25% crystal fractionation, again under distinct ƒO₂-ƒH₂O conditions. Reconstruction of the P-T-ƒO₂-ƒ’H₂O conditions of the andesite to rhyolite magmas are consistent with the existence of a compositional and thermal gradient prior to the eruption. Magma mingling/mixing between the basalt to andesite and main compositionally zoned rhyolitic magma occurred during caldera-collapse, modifying the least-evolved rhyolite at the bottom of the reservoir and effectively destroying the pre-eruptive gradients. A detailed examination of the diverse range of calcic-amphibole compositions from the ca. 330 ka Matahina eruption (ca. 160 km³ rhyolitic magma) of the Okataina Volcanic Complex, Taupo Volcanic Zone, including crystal-rich basalt to dacite pumice from post-collapse deposits, reveals several pre- and syn-eruption magmatic processes. (1) Amphibole phenocrysts in the basaltic-andesite and andesite crystallized at the highest pressures and temperatures (P: up to 0.6±0.06 GPa and T: up to 950°C), equivalent to mid-crustal depths (13-22 km). Inter- and intra-crystalline compositions range from Ti-magnesiohornblende → Ti-tschermakite → tschermakite → magnesiohornblende and some display gradual decreases in T from core to rim, both consistent with magma differentiation by cooling at depth. (2) The largest amphibole crystals from the basaltic-andesite to andesite display several core to rim increases in T (up to 70°C), indicating new hotter magma periodically fluxed the crystal mush. (3) The dominant population of amphibole (magnesiohornblende) from the rhyolite is small and bladed and crystallized at low P-T conditions (P: 0.3 GPa, T: 765°C), equivalent to the eruptive P-T conditions. Amphibole (tschermakite-magnesiohornblende) from the dacitic and low-silica rhyolitic pumice form two distinct populations, which nucleated at two different T (High: 820°C and Low: 750°C). These compositional variations, governed primarily by differences in T conditions during crystal growth, record the mixing of two distinct amphibole populations that approached a thermal equilibrium at the eruptive T. Therefore, the diversity in amphibole compositions can be reconciled as an exchange of crystals+liquid between the basaltic-andesite to dacite from the mid-crust and rhyolite from the upper-crust, which quenched against one another, modifying the dacite to low-silica rhyolite compositions as the eruption progressed.
505

The SWHEL model for studying B cell responses in tolerance and immunity

Phan, Tri Giang January 2005 (has links)
Classical immunoglobulin transgenic (Ig-Tg) mouse models such as the MD4 anti-hen egg lysozyme (-HEL) Ig-Tg line have been used extensively to study B cell responses in tolerance and immunity. This thesis describes a new generation of gene-targeted mice (designated SWHEL mice) whereby the VH10 Ig variable gene encoding the HyHEL-10 specificity of the original anti-HEL Ig-Tg mouse was targeted to the Ig heavy chain locus. B cells in the SWHEL mouse are therefore capable of undergoing class switch recombination (CSR) and somatic hypermutation (SHM), representing a major advance on the original MD4 mouse model. SWHEL mice were found to not only contain a large population of HEL-specific (HEL+) B cells but also a significant population of non-HEL-binding (HEL-) B cells generated by VH gene replacement. HEL+ SWHEL B cells were found to belong to the B2 lineage and displayed high levels of surface IgM. Nevertheless, they matured normally and colonised the primary B cell follicle and marginal zone (MZ) of the spleen. The SWHEL model thus provided an opportunity to re-examine some of the original observations made in the MD4 system and also to extend these observations, particularly with regard to the regulation of CSR by self-reactive B cells. As expected, analysis of SWHEL B cells exposed to high avidity membrane-bound HEL revealed that they underwent clonal deletion in the bone marrow (BM). More interestingly, analysis of HEL+ B cells exposed to low avidity soluble HEL revealed that they were able to emigrate from the BM to the spleen as anergic B cells. However, unlike anergic MD4 B cells, anergic SWHEL B cells were reduced in frequency, displayed an immature B cell phenotype, were excluded from the follicle and had a reduced lifespan. Direct measurement of B cell antigen receptor (BCR) occupancy by HEL and the frequency of HEL- competitor B cells was combined with mixed BM irradiation chimeras to demonstrate unequivocally that the difference in phenotype and fate of HEL+ B cells in the two systems was due solely to competition from HEL- B cells. In addition, the SWHEL model of B cell self-tolerance was used to show that while self-reactive B cells were hypo-responsive to BCR stimulation, BCR-independent signals delivered via anti-CD40 plus IL-4 or lipopolysaccharide could trigger them to undergo CSR and secretion of potentially pathogenic isotype-switched autoantibodies. Finally, the SWHEL model was used to study the responses of adoptively transferred follicular (Fo) and MZ B cells to in vivo activation with HEL conjugated to sheep red blood cells (HEL-SRBC). These studies revealed that both HEL+ MZ and Fo B cells were capable of mounting a robust T cell-dependent IgG1 antibody response to HEL-SRBC. However, HEL+ MZ B cells did not efficiently localise to the T cell-B cell border following antigen engagement and preferentially migrated to the bridging channels and red pulp. In contrast, HEL+ Fo B cells rapidly localised to the T cell-B cell border and subsequently colonised numerous germinal centres. As a result, the rate and pattern of SHM by HEL+ Fo and MZ B cells was shown to be distinct, with preferential targeting of mutations to the second complementarity-determining region in the former and to the second framework region in the latter. Together these data indicate illustrate the value of the SWHEL model and its potential to greatly advance the current understanding of B cell responses in tolerance and immunity.
506

Enhancing student performance in the Australian Mathematics Competition : a heuristic-based intervention technique using Vygotsky's 'Zone of proximal development' principle.

Ireland, Dennis V. January 1985 (has links)
The purpose of this study was to attempt to enhance performance in the Australian Mathematics Competition of a group of Western Australian Year 9 students, to a level beyond that which they might have been expected to attain, through the use of a heuristic-based intervention technique using Vygotsky's zone of proximal development principle.Since 1978, students of mathematics in Australian high schools have been meeting the challenge of the Australian Mathematics Competition. This national competition aims to provide students with a sense of achievement in mathematics and to emphasise the importance of this subject in the high school curriculum.Vygotsky's zone of proximal development refers to the difference between a student's actual developmental level and the student's potential developmental level given adult assistance. In effect, this means that while students may achieve to a plane commensurate with their actual developmental level, they will progress into their zone of proximal development with assistance and their level of achievement will rise. Vygotsky's concept of Intervention coupled with Siegler's concept of heuristic-based strategy learning provided a methodology suitable for enhancing and maximising developmental effects in this study.The study involved three distinct stages: the preparatory phase, the treatment phase and the concluding phase.In the preparatory phase, student's actual developmental levels were determined based on their performance in the 1979 Junior level Australian Mathematics Competition paper. This data facilitated identifying the paths that learning should follow in order that students' problem solving skills should improve. During this phase, students also attempted an Australian Council for Educational Research (ACER) test entitled 'Test's of Reasoning in Mathematics' (TRIM). This measure was used to monitor expected development ++ / in mathematics reasoning ability for students over the period of the study.The treatment phase involved the students in over 35 hours of instruction which exposed them to a heuristic-based intervention technique designed to enhance their performance in problem solving. Students practised various problem solving techniques and the Australian Mathematics Competition ittself became the focus for improved performance.An index of improvement was provided in the concluding phase of the study by scores obtained from the treatment group on the 1982 Intermediate level Australian Mathematics Competition paper. Scores were significantly higher than the national average of either the Year 9 or Year 10 groups. The second ACER 'TRIM' test verified that the students achieved their expected development in mathematics reasoning ability during the study.The implication of this result is that the practice of restricting students to year groups or courses on the basis of age should be examined in the light of the Vygotskian principle.
507

The concept of ecological sustainability and coastal development, with reference to South Australia /

Situmorang, Rahel. January 1992 (has links) (PDF)
Thesis (M. Plan.)--University of Adelaide, Dept. of Architecture, 1993. / Includes bibliographical references (leaves 115-125).
508

Crustal modification by tectonic events and upper mantle anisotropy beneath the Midcontinent Rift and New Madrid Seismic Zone: insights from receiver function studies and teleseismic shear wave splitting

Moidaki, Moikwathai, January 2009 (has links) (PDF)
Thesis (Ph. D.)--Missouri University of Science and Technology, 2009. / Vita. The entire thesis text is included in file. Title from title screen of thesis/dissertation PDF file (viewed April 29, 2009) Includes bibliographical references (p. 119-131).
509

Oceanic hazard risk in low-lying areas of Hong Kong

Chu, Tai-wai, David. January 2007 (has links)
Thesis (M. Sc.)--University of Hong Kong, 2007. / Title proper from title frame. Also available in printed format.
510

Using microtremors to assess site characteristics in the New Madrid seismic zone

Hardesty, Kelli April, Wolf, Lorraine W., January 2008 (has links) (PDF)
Thesis (M.S.)--Auburn University, 2008. / Abstract. Vita. Includes bibliographical references (p. 69-74).

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