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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

Lohengrin

Cramer, Thomas, January 1971 (has links)
Habilitationsschrift--Karlsruhe. / Bibliography: p. 584-589.
2

An assessment of impacts of mute swans (Cygnus olor) on submerged aquatic vegetation (SAV) in Chesapeake Bay, Maryland

Tatu, Ketan. January 2006 (has links)
Thesis (Ph. D.)--West Virginia University, 2006. / Title from document title page. Document formatted into pages; contains xvi, 161 p. : ill. (some col.), maps (some part col.). Includes abstract. Includes bibliographical references.
3

Wind-wave measurements in a shallow estuary: Trinity Bay, Texas

Dupuis, Keith Wade 15 May 2009 (has links)
Acoustic current meter data collected in the shallow ( 3m depth) Trinity Bay, (TB a sub-bay in Galveston Bay), TX, estuary were used to characterize locally generated windwaves. Significant wave heights, periods, and directions were estimated from dynamic pressure time-series (P; near bottom) and horizontal current velocities (U, V). Surface wave spectra were calculated from the pressure time-series and fitted to the empirical shallowwater Texel, Marsen, and Arsloe wave spectrum. The mean shape parameters used to define the TB wave spectra were:alpha = 0:016, gamma = 4:26, sigma-a = 0:063, sigma-b = 0:089. Waves heights were also hindcast using empirical and numerical models. The empirical formulas were derived from fetch-limited shallow water observations and follow the current proposed asymptotic limit to wave growth in shallow depth. The depth range for this empirical formulation is extended from 0.5–2m out to 3.5m. The model does not work for wind speeds less than 1m/s and during rapid wind direction changes. The Shallow WAves Nearshore numerical model was implemented in a Galveston Bay (GB; encompassing TB) computational domain. The model was forced with wind speeds and directions measured on-site and in four surrounding locations maintained by the NOAA PORTS. Currents measured on-site in TB and calculated bottom frictions were input homogeneously in space. The model was run in steady and unsteady conditions, and the modeled wave spectra were compared to the observations. The modeled wave spectra do not recreate the observed spectral shape for the steady and unsteady conditions. However, the total wave energy is represented in the unsteady conditions. In both the steady and unsteady cases, the wave period is underpredicted by one-half times the observed spectra and the model direction agrees with the observed wave directions.
4

Sequence Stratigraphy and Detrital Zircon Geochronology of the Swan Peak Quartzite, Southeastern Idaho

Wulf, Tracy David 2011 December 1900 (has links)
The supermature Middle-Late Ordovician Swan Peak quartz arenite was deposited on the western Laurentia passive margin and is very fine to fine grained, well-rounded, well-sorted, and silica-cemented. Laurentia was positioned over the equator during the Middle-Late Ordovician, suggesting that basement rock along the Transcontinental Arch was intensely eroded in a humid climate to produce this and other coeval quartz arenites. To determine provenance for the Swan Peak Quartzite, zircon grains were analyzed using LA-ICP-MS and the results were constrained within a sequence stratigraphic framework. Depositional environments of the Swan Peak Quartzite record an offshore-to-onshore transition with five facies (A-E). Facies A only occurs at the base of the Bear Lake section and may record an incised valley or localized embayment. It is the deepest water facies in the succession containing shale and quartz arenite interbeds. Facies B through E are interpreted as lower, middle, upper shoreface/foreshore depositional environments, respectively, based on primary sedimentary structures and bioturbation. Detrital zircon age spectra of the Swan Peak Quartzite have four distinct populations: the two main populations are at 1.8 - 2.0 Ga (Paleoproterozoic) and between 2.5 - 3.0 Ga (Archean), with a smaller, but persistent, population at 2.0 - 2.1 Ga, and a very minor 0.8 - 1.2 Ga (Mesoproterozoic) population occurring mainly in the tops of the measured sections. The base of each section has a larger Archean peak whereas the top of each section is predominantly Paleoproterozoic grains. Zircon data have overlap and similarity values ranging between 0.531 - 0.771 and 0.506 - 0.881, respectively, which indicates zircon age spectra of the Swan Peak Quartzite is similar to other Cordilleran Ordovician quartzites and that recycling of heterogeneous underlying sedimentary rocks was minimal. The Wyoming Craton (2.5 - 2.8 Ga) and the Trans-Hudson Orogen (1.8 - 2.0 Ga) provinces near the paleoequator likely provided the majority of zircons in the Swan Peak Quartzite. The source for the 2.0 - 2.1 Ga grains is currently unknown and the 0.8 - 1.2 Ga grains are interpreted to reflect Mesoproterozoic Laurentian tectonism. Sediment input varied in response to sea level fluctuations. Longshore transport was likely an important process in redistributing grains along the coastline during later deposition of the Swan Peak Quartzite.
5

The ecology of free-living nematodes in nearshore marine and estuarine sediments of the microtidal lower west coast of Australia.

m.hourston@iinet.net.au, Mathew Hourston January 2009 (has links)
The overarching aim of this thesis was to describe the ecology of the assemblages of free-living nematodes in the sediments of nearshore marine and estuarine waters on the microtidal lower west coast of Australia. The thesis also provides descriptions of ten previously undescribed species as well as develops and tests a habitat classification scheme for the Swan River Estuary using these biotic assemblages. The first section of my thesis has determined the ways in which the characteristics of the nematode assemblages in nearshore marine waters along the microtidal lower west coast of Australia are related to habitat type, time of year and shore-perpendicular zones. Three habitat types, which had previously been identified on the basis of a suite of enduring environmental characteristics, could be broadly described as highly sheltered from wave activity and containing dense seagrass (habitat type 1), moderately sheltered from wave activity and with sparse seagrass (habitat type 2) and relatively exposed to wave activity and with no seagrass (habitat type 6). Sampling in five consecutive seasons yielded > 15 000 nematodes, representing 75 species. The number of species and densities in habitat type 1, and particularly those in its subtidal zone, were far greater than those in the other two habitat types. Both of these biotic variables underwent marked seasonal changes, declining to low levels during winter. The compositions of the assemblages differed significantly among the three habitat types, with the differences between habitat types 1 and 6 being particularly marked. Paracomesoma sipho, Dichromadora sp., Marylynnia annae and Pomponema sp., which, on the basis of their buccal cavity morphology, are assumed to feed primarily on benthic diatoms, were particularly abundant at the most sheltered habitat type, whereas Gonionchus australis, Theristus sp. and Bathylaimus australis, which are assumed to be deposit feeders, were relatively abundant at the most highly exposed habitat type. The compositions of the assemblages differed among seasons and were most discrete in spring, due to marked increases in the densities of certain species. However, differences in the compositions in the different zones of each habitat type were relatively small, presumably reflecting the influence of the small tidal regime of this region. The second component of this thesis has determined the ways in which the density, number of species, species composition and trophic structure of free-living nematode assemblages in the subtidal waters of a large microtidal estuary change spatially and temporally, and has explored whether those four biotic characteristics are related to certain environmental factors. Based on data derived from samples collected seasonally at 12 sites throughout the estuary, the densities and number of species of nematodes decreased progressively with distance from estuary mouth, to reach a minimum at sites where salinities were most variable, and then increased slightly in the uppermost part of the estuary where salinities were least. Densities were also generally greatest in spring, due largely to increases in the abundance of epistrate-grazing species at the time when the amount of primary food (microphytobenthos) peaked. The spatial distribution of the composition of the nematode assemblages was closely correlated with salinity and, to a lesser extent, grain-size composition and amount of particulate organic material in the sediment (%POM). Although species composition changed sequentially along the estuary, the change was particularly pronounced between sites above and below the area where salinities started to decline markedly and become more variable and %POM increased markedly. This reflected, in particular, far greater abundances of Spirinia parasitifera at the six downstream sites, and of Theristus sp. 1 at the six sites further upstream. Species composition underwent pronounced seasonal cyclical changes at all sites, presumably reflecting interspecific differences in the timing of peak reproduction and thus of recruitment. The trophic structure of the nematode assemblages changed both spatially and temporally in relation to the relative abundance of different food sources. Thus, for example, non-selective deposit feeders, such as Theristus sp. 1, dominated samples in the upper estuary, where %POM was by far the greatest, and was rare or absent at downstream sites. Conversely, epistrate grazers, such as species of the Chromadoridae, were most abundant at downstream sites in spring, when the density of the microphytobenthos reached its maximum. The data for the nematode assemblages in nearshore subtidal marine sediments of the lower west coast of Australia were compared with those in nearshore subtidal sediments in the upper and lower regions of the Swan River Estuary. The densities and average species richness in cores from the marine environment were much lower than in cores from both estuarine regions. However, the total number of species found in the marine environment was much greater than in the estuary. The compositions of the nematode assemblages were more variable in marine than estuarine sediments. The assemblages from the two estuarine regions were far more similar to each other than to those from the marine region at a species level, and also, but to a lesser extent, at the generic and family levels. While the trophic compositions of the nematode assemblages in the upper estuarine region was dominated by non-selective deposit feeding species and those of the lower estuarine region were dominated by epistrate grazing species during spring and non-selective deposit feeding species in other seasons, the dominant functional feeding groups varied among the sites representing the marine region. That variability presumably reflects differences in the relative contributions of the different potential food sources. Surprisingly, the trophic composition in the upper estuarine region, i.e. comprising predominantly non-selective deposit feeders, was similar to that at the very different environment of the most exposed marine site. The dominance of this feeding group at the marine site is assumed to be attributable to the fact that the only food source of any note is POM and, even then, it occurs in only small amounts. Taxonomic descriptions have been produced for ten new species of nematodes found during the ecological studies of the free-living aquatic nematofaunas of south-western Australia. These species were chosen because they were members of families for which the other species had been described and, in a number of cases, were important for distinguishing between the compositions of a priori groups. They comprised four species of Axonolaimidae, representing the genera Ascolaimus, Parascolaimus, Odontophora and Parodontophora, and six species of Desmodoridae, representing single species of Bolbonema, Eubostrichus, Catanema and Leptonemella and two species of Onyx. As a complement to the nematological study of the Swan River Estuary, a novel habitat classification system was developed and then applied in this environment. This system was based on enduring environmental characteristics and employed the relatively new multivariate statistical routines SIMPROF and LINKTREE. The applicability of habitat types produced by this classification system to biotic assemblages was tested using the data for the estuarine nematode assemblages described above. The results demonstrate that the compositions of the assemblages differed significantly among each of the habitat types defined by the classification system. While there were also significant differences between the compositions of the nematofaunas at sites belonging to the same habitat type, the extent of these differences were generally less than those between habitat types. A significant and strong correlation was also found between the spatial pattern exhibited by the environmental characteristics used to define habitat types, and that of the nematofauna.
6

A study of mute swans in relation to lead poisoning

Sears, J. January 1986 (has links)
No description available.
7

Timothy Swan, native American composer

Van Sickle, Paul R. January 1965 (has links)
Thesis (M.M.)--Boston University / PLEASE NOTE: Boston University Libraries did not receive an Authorization To Manage form for this thesis or dissertation. It is therefore not openly accessible, though it may be available by request. If you are the author or principal advisor of this work and would like to request open access for it, please contact us at open-help@bu.edu. Thank you. / 2031-01-01
8

Svanenmärkning av lamparmatur

Waldowsson, Sanna January 2008 (has links)
This degree project has been performed on commission by Örsjöbelysning AB. The task has been to study alighting armature and compare it to the demands of The Swan Ecolabel. The task was also to recommend adjustments to improve the environmental adaption of the product to meet the demands of The Swan Ecolabel. Furthermore the task has been to gather documentation on the elements of the lighting armature. Such documentation is required to obtain The Swan Ecolabel. The Swan Ecolabel's vision is a sustainable society, in which future generations can benefit from the same conditions and opportunities as we ourselves do. Everyone nowadays is very aware of the environment and its importance, this has led to higher expectations on the industry. That is why the use of Ecolabels is getting more and more common. The Swan is one of the most well known brands in Sweden. 2008: Nr 8 Teknik
9

Flows through s-shaped annular, inter-turbine diffusers

Norris, Glyn January 1998 (has links)
Inter-turbine diffusers or swan neck ducts (SND's) provide flow continuity between the H.P. and L.P. turbine, which with diffusing of the flow allow; greater stage efficiencies to be achieved as a consequence of reducing both the stage loading and flow coefficient of the L.P. turbine. This thesis presents an experimental and computational investigation into the local flow development and overall performance of two different severity diffusing annular sshaped ducts, with the same overall diffusion ratio of 1.5, in order to validate the CFD code M.E.F.P. The first less severe diffusing duct was used to investigate the effects of inlet swirl on the duct performance. It was found that at an optimum swirl angle of 15 degrees, the duct total pressure loss coefficient was approximately half the value at 0 or 30 degrees swirl. The second more severely diffusing duct had simple symmetrical aerofoil struts added, which simulated struts required in real inter-turbine diffusers to support inner shafts and supply vital engine services. The total pressure loss developed by the 30% shorter duct was 15% greater that of the longer duct, and when struts were added to the second duct the loss almost doubled. These increases were attributed to gradually worsening casing surface flow separations which also acted to reduce the overall static pressure recovery of the ducts as their losses increased. The computational investigations were made on the more severe duct with and without struts. The code, Moore's Elliptic Flow Solver (M.E.F.P) which used a mixing length model, predicted flow separation in the strutted duct case albeit in slightly the wrong position, however, it failed to predict any secondary flow for the unstrutted case and hence correlated worse with the measured results. This was also true of the results predicted by a version of Dawes BTOB3D.
10

Understanding sustainable tourism development from a complex systems perspective a case study of the Swan River, Western Australia /

McDonald, Janine. January 2006 (has links)
Thesis (Ph.D.)--Edith Cowan University, 2006. / Submitted to the Faculty of Business and Law. Includes bibliographical references.

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