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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.
91

A real-time parallel processing system for synthetic aperture sonar

Lawlor, Michael Andrew January 1997 (has links)
No description available.
92

Vztah funkce pánevního dna k respiraci / The relation of the function of the pelvic floor to respiration

Matějková, Andrea January 2016 (has links)
Author of the Thesis: Bc. Andrea Matějková Supervisor of the Thesis: doc. Ing. Monika Šorfová, Ph.D. Title of the Thesis: Relation of function of the pelvic floor to respiration Year of the presentation of the thesis : 2016 Powered by TCPDF (www.tcpdf.org)
93

An investigation into the detection of seafloor massive sulphides through sonar

Mitchley, Michael 23 February 2012 (has links)
M.Sc., Faculty of Science, University of the Witwatersrand, 2011 / Sea oor massive sulphides are deep sea mineral deposits currently being examined as a potential mining resource. Locating these deposits, which occur at depths in the order of 2km, is currently performed by expensive submersible sonar platforms as conventional sonar bathymetry products gathered by sea surface platforms do not achieve adequate spatial resolution. This document examines the use of so-called high resolution beamforming methods (such as MUSIC and ESPRIT) for sonar bathymetry, together with combinations of parameter estimation techniques, including techniques for full rank covariance matrix estimation and signal enumeration. These methods are tested for bathymetric pro le accuracy using simulated data, and compared to conventional bathymetric methods. It was found that high resolution methods achieved greater bathymetric accuracy and higher resolution than conventional beamforming. These methods were also robust in the presence of unwanted persistent signals and low signal to noise ratios.
94

Tecnologia de produção de contrapisos para edifícios habitacionais e comerciais. / Production technology of subfloors for buildings.

Barros, Mércia Maria Semensato Bottura de 20 June 1991 (has links)
O trabalho propõe uma metodologia de produção de contra pisos para edifícios residenciais e comerciais, envolvendo a dosagem racional da argamassa, a técnica de execução e as diretrizes para a elaboração do projeto e para a implantação do controle da produção. Para isto, realizou-se, uma síntese da evolução do subsistema piso desde o início do século até os dias atuais, abordando uma de suas camadas - o contrapiso, para o qual destacou-se as suas funções e propriedades. Além disto, foram estudadas as características de produção do contrapiso enfocando-se as argamassas, as técnicas de execução e os procedimentos de controle recomendados pela bibliografia. Com base na bibliografia realizou-se um trabalho experimental em canteiros de obra e em laboratório buscando-se conhecer as atuais condições de execução do contrapiso no Brasil, e as fases de produção passíveis de serem alteradas, buscando uma produção racionalizada. O trabalho, após a implantação da metodologia em caráter experimental, conclui com a constatação de que ha uma necessidade premente de desenvolvimento de tecnologias construtivas adequadas a realidade nacional, voltadas a produção de edifícios pelo processo convencional e que tais tecnólogias deverão estar aliadas a elaboração do projeto dos diversos subsistemas do edifício e a implantação de específicos procedimentos de controle do processo de produção. / A brief description of the evolution of the floor sub-system for buildings since the beginning of this century is presented. The layers of the floor are characterized with emphasis on the functions and properties of the screed layer. Based on a literature review, the characteristics of the screed layer are analysed as well as the mix design, production techniques and quality control procedures. The experimental work was carried out both in the laboratory and at the working site in order to know better the present screed layer production conditions in Brazil, aiming to improve them. From the experimental work, a screed production methodology for housing and commercial buildings is proposed and consists of: - the production techniques taking into account the Brazilian conditions; - the floor sub-system design guidelines; - the on-site quality control methodology. This methodology was applied on experimental basis. The conclusion is that the development of building technologies taking into account the actual site conditions is important for improvement of the construction industry in Brazil. Moreover, these technologies must be consistent with the design procedures of the different building sub-systems and also with the procedures of the buildings production control.
95

Geometry and geobody extraction of a submarine channel complex in the Sable Field, Bredasdorp Basin

Stoltenkamp, Razeen January 2015 (has links)
>Magister Scientiae - MSc / The Sable Field constitutes a Basin Floor Channel (BFC) complex (E-BD reservoir) and a Basin Floor Fan (BFF) complex (E-CE reservoir). The reservoir sands were deposited during early-drift sedimentation in the Bredasdorp Basin. Paleo-current flows from the west, filling the basin with sediments that are eroded off the continental shelf (Agulhus Arch) and deposited on the base of the continental slope and basin floor. Turbidite flows off the Agulhus arch have deposited the Sable Fields reservoirs, where the larger channelized reservoir body takes an 80° bend off the continental slope and flows onto the basin floor. This 3-D reservoir highlights the reservoirs internal heterogeneity and complexity at the well bore and away from the well bore. Well tops tie wells to the 3-D seismic cube for; reservoir location and delineation, velocity modelling and subsequent conversion of the mapped surfaces from time to depth. Core and petro-physical analysis were used to outline the depositional facies within the investigated wells namely: E-BD5, E-BD2, E-BD1 and E-CE1. Correlation of depositional facies at the well bore with their corresponding seismic facies, allows for extrapolation of facies away from the well bore. The internal heterogeneity of the reservoir is outlined using an integrated methodology, which is based on log scale depositional features (channels, sheets, lobes) that are extrapolated to field scale (sand rich complex) using corresponding top and base reservoir seismic responses. The investigated thick region of sediment accumulation on: the continental slope, the base of the continental slope and basin floor is deposited on the 13AT1 early drift unconformity. The reservoir is outlined from the up-dip to the down-dip reaches of the field. Well E–BD5 has tapped into the proximal region (up-dip), with reservoir comprising of amalgamated channel sands that are deposited by laterally switching and stacking channelized sand bodies. Channel meander facies are seen in the upper portion of the reservoir, with massive channel fill in the lower parts. The channel fill constitutes a high net to gross with little to no lateral facies variations. This confined environment is dominated by amalgamated massive sands (on-axis) that are thinner bedded towards the banks of the channels (off-axis). A high degree of channel amalgamation has been interpreted in both up-dip wells E-BD5 and E-BD2. This channelized reservoir is at least 2km wide and 6km long, before the larger channel makes a rapid 80° change in paleo-current direction. This is possibly the result of basin floor topography and the stacking of previously deposited sand complexes which alter local sea floor topography. The vertical and lateral continuity of the channelised reservoir is generally excellent due to the high degree of channel amalgamation. The stacked channel complex constitutes a gross thickness of 76.2m (68.5m Net sand) in well E-BD5, and a gross thickness 25m (23m Net sand) in well E-BD2. Channel sands in well E-BD5 have an average porosity of 15% while the average porosity of channel sands in well E-BD2 (further down-dip) is 17%. This up-dip channelised region results in high amplitude reflections due to hydrocarbon charged sand juxtaposed against hemipelagic muds and silty levee facies. Well E-BD1 has tapped into a relatively confined sand complex deposited at the base of the continental slope. The amalgamated lobe and sheet sand complex is entirely encased in hemi pelagic mud. These reservoir sands are interpreted to be deposited in the Channel Lobe Transition Zone (CLTZ), thus the reservoir sands are interpreted to have a transitional depositional style (generally channelized sheets). The CLTZ region is thus dominated by both channel complex and lobe complex elements. The E-BD1 reservoir constitutes a number of amalgamated elements that result in a reservoir zone with an average porosity of 16.4%. These include: amalgamated thick bedded sheet sand (lobe axis) associated with deep depositional feeder channels; thin bedded sheet sands (off lobe axis), broad thin amalgamated lobe elements, layered thick bedded sand sheets and deep broad depositional channels. The low sinuosity broad depositional-channels and elongate lobe elements are expressed as lobate amalgamated sheets of sand which is up to 2-3km wide, 5km long and 30m thick (29.7m nett sand) at the well bore. Well E-CE1 has intersected 50m thick reservoir sand (50m nett sand) which constitutes the axis of a lobe complex where the reservoir zone has an average porosity of 14%. The sand rich complex is deposited on the unconfined basin floor. This reservoir complex constitutes amalgamated thick bedded lobe architectural elements which are massive in nature. The laterally continuous hydrocarbon charged lobe elements result in bright parallel seismic reflections. The amalgamated lobe complex is more than 5km wide. Sub-parallel horizons are attributed to the thin bedded off axis portion of the lobe complex where the net to gross is considerably less than the highly amalgamated axis of the lobe complex. The lobe complex has a moderate to good net to gross of 40-60%. The high aspect ratio of the lobe complex severely impacts the reservoirs vertical permeability, however horizontal permeability is quite good due to the extensive lateral continuity of good quality sheet sands. Based on the nature deep water architectural elements observed in this study, the internal heterogeneity of the Basin floor Fan and Basin floor channel complex’s may constitute an entire sand rich reservoir zone. All the sands may be in hydraulic communication if they are genetically related. These sands and stretch from the up-dip (wells E-BD5 & E-BD2) through to the transitional (E-BD2) and pinching out in the distal regions (E-CE1) on the basin floor. The seal constitutes a prominent shale horizon T13PW3 (8-10m thick) which is draped over the entire reservoir complex. This top seal is extrapolated from all the wells and correlated with seismic facies, thus outlining the lateral continuity and thickness variations of the top seal. This draped shale horizon exposes the thick axial portion of the amalgamated channel complex and amalgamated lobe complex.
96

Tectonic consequences of mid-ocean ridge evolution and subduction

Whittaker, Joanne January 2008 (has links)
Doctor of Philosophy(PhD) / Mid-ocean ridges are a fundamental but insufficiently understood component of the global plate tectonic system. Mid-ocean ridges control the landscape of the Earth's ocean basins through seafloor spreading and influence the evolution of overriding plate margins during midocean ridge subduction. The majority of new crust created at the surface of the Earth is formed at mid-ocean ridges and the accretion process strongly influences the morphology of the seafloor, which interacts with ocean currents and mixing to influence ocean circulation and regional and global climate. Seafloor spreading rates are well known to influence oceanic basement topography. However, I show that parameters such as mantle conditions and spreading obliquity also play significant roles in modulating seafloor topography. I find that high mantle temperatures are associated with smooth oceanic basement, while cold and/or depleted mantle is associated with rough basement topography. In addition spreading obliquities greater than > 45° lead to extreme seafloor roughness. These results provide a predictive framework for reconstructing the seafloor of ancient oceans, a fundamental input required for modelling ocean-mixing in palaeoclimate studies. The importance of being able to accurately predict the morphology of vanished ocean floor is demonstrated by a regional analysis of the Adare Trough, which shows through an analysis of seismic stratigraphy how a relatively rough bathymetric feature can strongly influence the flow of ocean bottom currents. As well as seafloor, mid-ocean ridges influence the composition and morphology of overriding plate margins as they are consumed by subduction, with implications for landscape and natural resources development. Mid-ocean ridge subduction also effects the morphology and composition of the overriding plate margin by influencing the tectonic regime experienced by the overriding plate margin and impacting on the volume, composition and timing of arc-volcanism. Investigation of the Wharton Ridge slab window that formed beneath Sundaland between 70 Ma and 43 Ma reveals that although the relative motion of an overriding plate margin is the dominant force effecting tectonic regime on the overriding plate margin, this can be overridden by extension caused by the underlying slab window. Mid-ocean ridge subduction can also affect the balance of global plate motions. A longstanding controversy in global tectonics concerns the ultimate driving forces that cause periodic plate reorganisations. I find strong evidence supporting the hypothesis that the plates themselves drive instabilities in the plate-mantle system rather than major mantle overturns being the driving mechanism. I find that rapid sub-parallel subduction of the Izanagi mid-ocean ridge and subsequent catastrophic slab break o_ likely precipitated a global plate reorganisation event that formed the Emperor-Hawaii bend, and the change in relative plate motion between Australia and Antarctica at approximately 50 Ma
97

Motivational aspects, benefits and pitfalls of a reward system in a small shop-floor business unit : A case study of a car-dealership service unit

Fransson, Thomas, Frendberg, Gabriel January 2008 (has links)
Introduction: Competition increases and companies need to adjust their business to stay competitive. Employees have gained an important for an or-ganisation and are often seen as the key to business success. Motiva-tion is important for increased performance. A reward system can, amongst other things, help an organisation to motivate, attract and retain their employees. Historically, rewards have concerned mostly senior management. We where interested in how a reward system could affect people further down in the hierarchy. How can a reward system influence motivation in small shop-floor business units? What are the benefits and possible pitfalls with a reward system for such a setting? Purpose: The purpose of this report is slightly wider than what the research questions suggest. By thoroughly investigating the motivating ele-ments we aim to create a frame of reference, which is thought to give insight into the important components of a reward system and the motivating factors. It is our aim that this frame will be applicable to other settings similar to the one which we will investigate. We also intend to look into what positive and negative aspects there are and how the disadvantages with a reward system can be minimized. Method: To fulfil our purpose we have chosen to perform a case study on the service unit of Hedin Göteborg Bil AB. In order to retrieve the necessary empirical data we have interviewed two managers and car-ried out a questionnaire amongst the thirteen service technicians. Results: In line with theory, we found that financial rewards it is not the prime source for motivation; there are many factors that play a lar-ger role. Some of the most motivating factors turned out to be col-leges, autonomy and responsibility, fun and rewarding work tasks. More interestingly, we saw a relation between many of these and the reward system, indicating that financial rewards enhance the motiva-tional effects of other factors. We found that there are several positive and negative aspects with any reward system. The case study presented solutions to many of the possible pitfalls and indicated that they benefited from their cur-rent reward system.
98

Development of Sidescan Sonar Image Mosaicing Software

Hsueh, Du-ying 22 August 2007 (has links)
Sidescan Sonar has been the most popular probe for sea floor detecting in the underwater engineering. It is not only use to map the topography of the sea floor but also apply to the underwater search and rescue. Sidescan Sonar relies on commercial software, e.g. SonarPro, to record the raw data and draw images of the sea floor. However, SonarPro only presents the data to display segmental images, but it can not illustrate all images of the sea floor in one drawing. Researchers need to use the other software, called WizMap, to mosaic all Sidescan images in one drawing. WizMap is powerful for analyzing Sidescan data, but it is costly and has never been published its technology of Sidescan mosaic images. Thus we can not understand how Wizmap analysis raw data and make a mosaic drawing. Moreover, we could only accept the results it made, even the mosaic drawing is not correct. In this study, we implement a new analysis software package to facilitate reading raw data and drawing mosaic images of Sidescan Sonar. Sidescan Sonar provides basic function to record all digital raw data including GPS position, heading, roll, pitch, etc. We transfer the ship and Sidescan location from GPS to TM2 coordinate and illustrate the two side images along Sidescan trace in the same drawing. We will review the drawing and check all characteristics of these images and then adjust the heading offset and location offset to fit a better mosaic drawing. Finally, we combine all images into one mosaic drawing and compare two drawings between WizMap mosaic image and our mosaic drawing for confirming all results.
99

Depositional Architecture of a Near-Slope Turbidite Succession: Upper Kaza Group, Windermere Supergroup, Castle Creek, British Columbia, Canada

Rocheleau, Jonathan 26 July 2011 (has links)
An expansive panel of well exposed (periglacial) strata of the Upper Kaza Group permitted a detailed study of the stratal architecture of proximal basin floor deposits in the Neoproterozoic Windermere turbidite system. Detailed stratigraphic and petrographic analyses identified six lithofacies: poorly-sorted, clast-rich mudstone (F1), thin-bedded siltstone and mudstone (F2), thick-bedded, massive sandstone (F3), medium-scale, cross-stratified sandstone (F4), mudstone-clast breccia (F5), and medium-bedded turbidites (F6). The spatial distribution of these facies identify five architectural elements: heterolithic feeder channel deposits (FA1), thin-bedded intralobe turbidites (FA2), terminal splay deposits (FA3), distributary channel deposits (FA4), and isolated scours (FA5). FA 1-4 are genetically related and form the basic building blocks of large-scale basin floor depositional lobes. FA 5, which is isolated to the stratigraphic top of the study area, is interpreted to have formed in a base-of-slope setting, and its superposition on FA 1-4 suggests the long-term progradation of the Windermere turbidite system.
100

Behaviour of channel shear connectors : push-out tests

Pashan, Amit 06 April 2006
This thesis summarizes the results of an experimental investigation involving the testing of push-out specimens with channel shear connectors. The test program involved the testing of 78 push-out specimens and was aimed at the development of new equations for channel shear connectors embedded in solid concrete slabs and slabs with wide ribbed metal deck oriented parallel to the beam. <p>The test specimens were designed to study the effect of a number of parameters on the shear capacity of channel shear connectors. Six series of push-out specimens were tested in two phases. The primary difference between the two phases was the height of the channel connector. Other test parameters included the compressive strength of concrete, the length and the web thickness of the channel. <p>Three different types of failure mechanisms were observed. In specimens with higher strength concrete, failure was caused by the fracture of the channel near the fillet with the channel web acting like a cantilever beam. Crushing-splitting of concrete was the observed mode of failure in specimens with solid slabs when lower strength concrete was used. In most of the specimens with metal deck slabs, a concrete shear plane type of failure was observed. In the specimens involving this type of failure, the channel connector remained intact and the concrete contained within the flute in front of channel web sheared off along the interface. <p>The load carrying capacity of a channel connector increased almost linearly with the increase in channel length. On average, the increase was about 39% when the channel length was increased from 50 mm to 100 mm. There was a further increase of 24% when the channel length was increased from 100 mm to 150 mm. The influence of web thickness of channel connector was significant when the failure occurred due to channel web fracture but was minimal for a concrete crushing-splitting type of failure. <p>The specimens with solid concrete slabs carried higher load compared to those with metal deck slabs. The increase in load capacity was 33% for specimens with 150 mm long channels but only 12% for those with 50 mm long channel connectors. <p>This investigation resulted in the development of a new equation for predicting the shear strength of channel connectors embedded in solid concrete slabs. The proposed equation provides much better correlation to test results than those obtained using the current CSA equation. <p>The results of specimens with metal deck slabs were used to develop a new equation for predicting the shear capacity of channel connectors embedded in slabs with metal deck oriented parallel to the beam. The values predicted by the proposed equation were in good agreement with the observed test values.

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