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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.
211

Theory and application of adaptive filter banks

Arrowood, Joseph Louis, Jr. 05 1900 (has links)
No description available.
212

The Use and Perceived Effectiveness of Recovery Modalities and Monitoring Techniques in Elite Sport

Melina Simjanovic Unknown Date (has links)
Post-exercise recovery techniques are being used increasingly in elite sport, but scientific study in this area is only emerging. The aim of this study was to collect information on the use and perceived effectiveness of the different recovery techniques used with athletes. Semi-structured interviews were conducted with 14 Queensland Academy of Sport coaches and other high-performance coaches from seven sports (three team sports and four individual sports). The interview questions sought to examine the coaches’ understanding of recovery, personal experiences, and the modalities and techniques used with their athletes. Interviews lasted an average of 45 minutes and were transcribed for qualitative content analysis and checked for accuracy by the coaches. Triangular consensus was used throughout the coding process to constantly revisit and redefine the open and axial codes that emerged. Three themes emerged: understanding of recovery, recovery modalities used, and monitoring of recovery. Understanding of recovery relates to the coaches’ overall view and general understanding of recovery. Coaches reported that recovery consisted of physical, mental and neural components, and is important to the overall performance, repeated performance, and training of athletes. Coaches gained their recovery knowledge from a variety of sources across their own athlete and coaching pathways. Transferring this knowledge to athletes was perceived as important for enabling athletes to implement and adhere to recovery within their training plans. The recovery modalities used most often were low-intensity activity, stretching, nutrition, massage, contrast water immersion, cryotherapy, sleep and rest. Practicality and accessibility (e.g., time and cost) for the athletes’ daily training environment were key factors influencing use of different recovery modalities. Coaches reported that they applied recovery modalities according to their own past coaching experiences or experiences of other coaches and sport science professionals. It appeared that coaches learn recovery information best by watching and speaking with others, especially other coaches and sports personnel. Factors contributing to use of recovery modalities include convenience and accessibility of a modality. Time restraint was an evident factor. Other factors that seem to contribute to the use of recovery modalities include the awareness of a modality’s existence, perceived modality strength of effect (or negative effect), and the compliance with and attitude of athletes to the modality. The personal experience of a coach using specific recovery modalities also impacted on whether the coach prescribed the modality and encouraged athletes to use the modality. However, it was clear from the study that athletes need to take responsibility for applying the recovery modalities themselves mainly because of logistical reasons. Recovery was monitored most often through informal observation rather than formal investigation. The most common monitoring approaches were coach observation and athlete reporting (diaries and discussions). Some coaches indicated that using a combination of approaches is useful and effective for gaining maximal benefits. Further investigation of monitoring approaches and prioritising them in terms of ease of implementation are needed. In summary, this study provided insight into the use of recovery modalities in elite sport and implications for use by professionals assisting coaches and athletes. In light of the limited research in some areas of recovery, a network could be established to capture the coaches’ learned experiences and information on recovery to share with each other across different sports.
213

Utilizacao do Au-198 com marcacao superficial no estudo do transporte solido por arraste de fundo em canal natural de grande porte

NAKAHIRA, SILVIO 09 October 2014 (has links)
Made available in DSpace on 2014-10-09T12:32:30Z (GMT). No. of bitstreams: 0 / Made available in DSpace on 2014-10-09T14:10:07Z (GMT). No. of bitstreams: 1 12894.pdf: 3496583 bytes, checksum: 5149c2b62809152eac0978234cafe18d (MD5) / Tese (Doutoramento) / IPEN/T / Escola Politecnica, Universidade de Sao Paulo - POLI/USP
214

Design and analysis of a system for 3D fabrication of synthetic anatomical structures

Nell, Raymond D January 2005 (has links)
Thesis (MTech (Electrical Engineering))--Cape Peninsula University of Technology, 2005 / This dissertation is the reading and display ofDICOM medical images (Digital Imaging and Communication in Medicine) and production ofmodel artifacts of anatomical organs using Rapid Prototyping An algorithm to read these DICOM medical images was developed. It also displays pixel information ofthe image. When the DICOM image has been read and displayed, the information required to produce the anatomical artifact is extracted. These 2D slice images, MRI (Magnetic Resonance Imaging) and CT Scan (Computer Tomography) images are written to 3D file in SLC (Slice files) and STL (Stereolithography File Format) format. A 3D softcopy ofthe anatomical structure is created. At this stage, the clinician or surgeon can make any changes or require additional information to be added to the anatomical structure. With the 3D model available in STL format, a physical artifact is produced using Rapid Prototyping. The external edge ofthe anatomical structure can be produced using Rapid Prototyping as well as the outer rim with the internal structures. To produce the external surface ofthe structure, an outer rim edge detection algorithm has been developed. This will only extract the external surface ofthe structure. In addition to the softcopy ofthe structure, multiple organs can be displayed on the same image and this will give a representation ofthe interaction ofneighboring organs and structures. This is useful as both the normal anatomy as well as the infiltration ofthe abnormal pathology can be viewed simultaneously. One of the major limitations ofdisplaying the information in a 3D image is that the files are very large. Since 3D STL files use triangles to display the outer surface ofa structure, a method to reduce the file size and still keep the image information was developed. The triangle reduction method is a method to display the 3D information and to decrease the STL file size depending on the complexity ofthe outer surface ofthe structure. To ensure that the anatomical model s represented as in the DlCOM files, an Interpolation Algorithm was developed to reconstruct the outer ofthe model from 2D MRI or CT-Scan images. A word about computer models: Some of the programs and presentations are based on the real world. They model the real world and anatomical structures. It is very important to note that the models are created with software. Obviously a model is useful if it resembles reality closely, but it is only a prediction about the model itself. Models are useful because they help to explain why certain things happen and how interaction takes place. Models provide suggestions for how structures might look. Computer models provide answers very quickly. These are computer models representing the real structure. (Czes Kosniowski, 1983)
215

Application and evaluation of electrocoagulation techniques for the treatment of dyehouse effluents

Thole, Andile January 2015 (has links)
Thesis submitted in fulfillment of the requirements for the degree Master of Technology Chemical Engineering In the Faculty of Engineering at the Cape Peninsula University of Technology / Wet textile processing (WTP), is faced with many challenges that are related to operating costs and market competiveness. WTP uses large amounts of water and electricity, which constitute a big portion of operating costs of dyehouses and other costs are related to releasing large quantities of water, high concentrations of dyes and chemicals into the textile effluents with possible effluents discharge limits (EDL) penalty charges if EDL are exceeded. EDL penalty costs had become a normative part of the operating costs for some WTP textile factories, making the EDL penalties, a monthly cost item, because water utilities and the effluent discharge are not controlled and optimized. Cotton dyeing is a complicated chemi-physical-sorption process that is not easy to perform efficiently. Inefficient dyeing (off-shades and un-level dyeing) sometimes results in several reprocessing steps, leading to mega litres of water and chemical usage. Inefficient dyeing can also lead to higher concentrations of dyes and chemicals in the dyeing effluents. The main objectives of this study were to investigate the applicability of electrocoagulation (EC) in treatment of reactive dyes textile effluents for safe discharge into sewers or forreuse and also to evaluate EC reaction kinetics in removal of various pollutants from reactive dyes textile effluent with a batch electrocoagulation reactor (ECR). To achieve these objectives; textile effluents to be used had to be created instead of using factory effluents because textile effluents vary between dyeing batches and reaction kinetics study require constant and consistent composition of effluents. This was done by following the standard commercial sample cotton-dyeing procedures. The dyeing and pre-bleaching procedures were formulated from literature sources. The dyeing and pre-bleaching were done to create the reactive dyes textile effluents with commercial sample dyeing machines; Washtec-P and Pyrotec-MB2 at liquor ratios of 10:1 and 20:1.
216

Content Visualization of GeoAudio Notes

Jusufi, Ilir, Junuzi, Lulzim January 2008 (has links)
The total population of GPS-enabled location-based services (LBS) subscribers is constantly increasing. This fact implies new research possibilities for visualizing geospatial data produced by these mobile devices. The aim of this thesis is to explore novel techniques and methods to visualize the content of voice notes (messages recorded by users on GPS-enabled devices) that will be placed in maps using GPS coordinates, and visualize the semantical, temporal, and spatial relations between the notes. Our research is part of the Geovisualization field which deals with geospatial data. Based on our research and analyzes of this problem, we combined different visualization and interaction techniques, thus providing a novel approach to achieve the research aim. We have built a prototype application, called GNV System (GeoAudio Notes Visualization System), that demonstrates our achievements.
217

Utilizacao do Au-198 com marcacao superficial no estudo do transporte solido por arraste de fundo em canal natural de grande porte

NAKAHIRA, SILVIO 09 October 2014 (has links)
Made available in DSpace on 2014-10-09T12:32:30Z (GMT). No. of bitstreams: 0 / Made available in DSpace on 2014-10-09T14:10:07Z (GMT). No. of bitstreams: 1 12894.pdf: 3496583 bytes, checksum: 5149c2b62809152eac0978234cafe18d (MD5) / Tese (Doutoramento) / IPEN/T / Escola Politecnica, Universidade de Sao Paulo - POLI/USP
218

Experiences of analogue-trained radiographers utilising digital imaging in projection radiography

Campbell, Sydney January 2017 (has links)
The professional work of a radiographer encompasses both patient care and the use of technology. The technology employed could either be analogue or digital technology. Since 1973, the analogue imaging system has slowly been replaced by digital radiography imaging systems. Despite the many advantages of digital imaging it does present the radiographer with added responsibilities. Furthermore, analogue-trained radiographers have found adjusting to digital imaging especially challenging. The aim of the study was to explore and describe the experiences of analogue-trained radiographers utilising digital imaging in projection radiography with the intention of developing guidelines to equip radiography managers to assist analogue-trained radiographers to better utilise digital imaging. The researcher used Schlossberg’s Transition Theory as a lens to look at the experiences of analogue-trained radiographers using digital imaging to produce radiographs. The research study used a qualitative design which was explorative, descriptive and contextual in nature. The target population included all diagnostic radiographers (public and private) in the local municipality who were registered with the Health Professions Council of South Africa. Purposive sampling was employed to select the radiographers that represented all radiographers in the Nelson Mandela Bay Health District. The sample included all radiographers who fulfilled the identified selection criteria. The selected participants were recruited to take part in in-depth, semi-structured individual interviews. The data was analysed using a computer-aided qualitative data analysis software package, ATLAS.ti. The trustworthiness of this study was ensured by applying Guba’s model of trustworthiness that includes credibility, transferability, dependability and confirmability. The ethical principles of respect for persons, beneficence and justice, as espoused by the Belmont Report, were adhered to in order to ensure that the study was conducted in an ethical manner. Two themes emanated from the data, namely the evolution of the radiographer when faced with the advances in technology as well the role that the work environment played in the manner that the participants experienced the change. The experiences of the participants were described using direct quotations from the interviews and a literature control was used to verify the participants’ experiences. Evidence was found of radiographer indifference towards exposure selection, dose optimisation and placement of anatomical side markers when utilising digital imaging. Finally, guidelines were developed to equip radiography managers to assist analogue-trained radiographers to better utilise digital imaging. In addition, the guidelines will assist all other radiographers to better utilise digital imaging.
219

Three’s Company: An Additional Non-transiting Super-Earth in the Bright HD 3167 System, and Masses for All Three Planets

Christiansen, Jessie L., Vanderburg, Andrew, Burt, Jennifer, Fulton, B. J., Batygin, Konstantin, Benneke, Björn, Brewer, John M., Charbonneau, David, Ciardi, David R., Cameron, Andrew Collier, Coughlin, Jeffrey L., Crossfield, Ian J. M., Dressing, Courtney, Greene, Thomas P., Howard, Andrew W., Latham, David W., Molinari, Emilio, Mortier, Annelies, Mullally, Fergal, Pepe, Francesco, Rice, Ken, Sinukoff, Evan, Sozzetti, Alessandro, Thompson, Susan E., Udry, Stéphane, Vogt, Steven S., Barman, Travis S., Batalha, Natasha E., Bouchy, François, Buchhave, Lars A., Butler, R. Paul, Cosentino, Rosario, Dupuy, Trent J., Ehrenreich, David, Fiorenzano, Aldo, Hansen, Brad M. S., Henning, Thomas, Hirsch, Lea, Holden, Bradford P., Isaacson, Howard T., Johnson, John A., Knutson, Heather A., Kosiarek, Molly, López-Morales, Mercedes, Lovis, Christophe, Malavolta, Luca, Mayor, Michel, Micela, Giuseppina, Motalebi, Fatemeh, Petigura, Erik, Phillips, David F., Piotto, Giampaolo, Rogers, Leslie A., Sasselov, Dimitar, Schlieder, Joshua E., Ségransan, Damien, Watson, Christopher A., Weiss, Lauren M. 31 August 2017 (has links)
HD 3167 is a bright (V = 8.9), nearby KO star observed by the NASA K2 mission (EPIC 220383386), hosting two small, short-period transiting planets. Here we present the results of a multi-site, multi-instrument radial-velocity campaign to characterize the HD 3167 system. The masses of the transiting planets are 5.02 +/- 0.38 M-circle plus for HD 3167 b, a hot super-Earth with a likely rocky composition (rho(b) = 5.6(-1.43)(+2.15) g cm(-3)), and 9.80(-1.24)(+1.30) M-circle plus for HD 3167 c, a warm sub-Neptune with a likely substantial volatile complement (rho(c) = 1.97(-0.59)(+0.94) g cm(-3)). We explore the possibility of atmospheric composition analysis and determine that planet c is amenable to transmission spectroscopy measurements, and planet b is a potential thermal emission target. We detect a third, non-transiting planet, HD 3167 d, with a period of 8.509 +/- 0.045 d (between planets b and c) and a minimum mass of 6.90 +/- 0.71 M-circle plus. We are able to constrain the mutual inclination of planet d with planets b and c: we rule out mutual inclinations below 1.degrees 3 because we do not observe transits of planet d. From 1.degrees 3 to 40 degrees, there are viewing geometries invoking special nodal configurations, which result in planet d not transiting some fraction of the time.
220

Interactive Transitions for Map Applications / Transitions interactives pour des applications cartographiques

Lobo, María Jesús 05 December 2017 (has links)
Les utilisateurs experts de SIG (Systèmes d'Information Géographique) doivent souvent mettre en relation et comparer des représentations hétérogènes d'une même région géographique. Par exemple, la mise à jour des bases des données géographiques, comme OpenStreetMap, nécessite une comparaison entre des cartes existantes et des images satellite récentes. Les moyens de combiner les cartes sont pourtant souvent limités à des techniques qui ne prennent pas en compte les données contenues dans les cartes, comme des techniques de superposition qui permettent de varier l'opacité de la couche supérieure. Ces techniques n'appuient pas efficacement les utilisateurs dans des tâches dans les domaines de l'analyse de crime ou la planification urbaine. Cette thèse vise à proposer des nouvelles transitions interactives pour combiner différentes représentations en une, soit de façon spatiale (multiplexage spatial) ou temporelle (multiplexage temporel). Afin de mieux comprendre les limites des techniques existantes, la première contribution de cette thèse est une évaluation de cinq techniques de comparaison de cartes interactives. On caractérise ces techniques par rapport à leur niveau de perturbation visuelle, de division de l'attention et leur stratégie de recherche. Pour les évaluer, on demande aux participants de trouver des différences entre des images aériennes et des cartes topographiques (modifiées à la main en ajoutant six types de différences). Les résultats suggèrent que les techniques qui superposent les couches sont plus efficaces que les techniques que les juxtaposent et qu'une stratégie de recherche motrice peut apporter des bénéfices pour certaines tâches. D'après les résultats de l'évaluation et des entretiens avec des utilisateurs experts en GIS, on introduit MapMosaic, la deuxième contribution de cette thèse. MapMosaic est une technique nouvelle de multiplexage spatial pour combiner des cartes. Ce modèle de composition dynamique permet aux utilisateurs de créer et manipuler des régions de composition locale de façon interactive, en considérant l'information sémantique et les attributs des objets et des champs. On a évalué MapMosaic en utilisant deux approches: premièrement, on compare son modèle d'interaction au modèle de QGIS (un logiciel SIG très utilisé) et MAPublisher (un outil cartographique professionnel) en utilisant les “Dimensions Cognitives” et avec une comparaison analytique, les résultats suggèrent que le modèle de MapMosaic est plus flexible et peut mieux appuyer les utilisateurs dans leur tâches. Ensuite, on rapporte des retours utilisateurs des experts qui confirment le potentiel de MapMosaic, grâce à des cas d'utilisation précis. Le multiplexage spatial peut être très utile pour comparer différentes couches géographiques. Cependant, le multiplexage temporal pourrait être plus approprié pour la représentation des dynamiques, puisque les changements peuvent être animes. Ceci pourrait être utile de façon particulière pour présenter des changements entre des images satellites, par exemple, pour montrer les effets du réchauffement climatique. Ainsi, la troisième contribution de la thèse est Baia: un cadre pour créer des transitions animées avancées, appelles plans d'animation, entre des couples d'images avant après. Baia est basé sur un modèle de transition par pixel qui permet de créer des animations très variées. Il reste simple d'utilisation grâce à des primitives d'animations prédéfinies permettant de représenter des changements géographiques communs facilement. On décrit le modèle et l'outil d'édition d'animation associé et deux études avec utilisateurs. Le premier suggère que les animations crées avec Baia sont perçues comme plus réalistes et focalisent mieux l'attention des spectateurs et le deuxième rassemble des retours sur l'outil d'édition d'animations. / GIS experts often need to relate and compare heterogeneous geographical representations of the same region. For example, existing maps are compared to recent satellite imagery to update geographic databases, like OpenStreetMap. The means to do so, are, however often limited to data agnostic techniques such as overlaying the representations with some degree of translucency or swiping between layers. These techniques do not support users effectively in their tasks in domains such as crime analysis or urban planning. This thesis aims at proposing new interactive transitions to combine those multiple representations into one, either spatially (spatial multiplexing) or temporally (temporal multiplexing).To better understand the limits of existing approaches, this thesis first contribution is an evaluation of five interactive map comparison techniques. We characterise these techniques in terms of visual interference, user attention and scanning strategy. We evaluate them by asking participants to find differences between real satellite imagery and topographic maps, that we purposefully modified introducing six kinds of differences. Results suggest that techniques that superimpose the layers are more efficient than techniques that juxtapose them and that having a more motor driven scanning strategy can be beneficial for some tasks. Drawing from the evaluation results and interviews with GIS experts, the second contribution of this thesis is MapMosaic: a novel spatial multiplexing technique to combine geographical layers. This dynamic compositing model enables users to interactively create and manipulate local composites of multiple vector and raster map layers, taking into account the semantics and attribute values of objects and fields. We evaluate MapMosaic using two approaches: first we compare MapMosaic’s interaction model to QGIS’ (a widely used desktop GIS) and MAPublisher’ (a professional cartography tool) using the ‘Cognitive Dimensions’ framework and through an analytical comparison, suggesting that MapMosaic’s model is more flexible and can support users more effectively in their tasks. Secondly, we report on feedback obtained from experts, which further confirms the potential of MapMosaic, by describing precise scenarios where it could be useful. Spatial multiplexing can be very useful when comparing different geographical layers. However, time multiplexing might be more suitable to represent dynamics, as changes can be animated. This can be particularly useful when presenting evolution across satellite images, to illustrate effects of climate change or a natural disaster’s impact. Thus, the third contribution of this thesis is Baia: a framework to create advanced animated transitions, called animation plans, between pairs of before-and-after images. Baia relies on a pixel-based transition model that gives authors much expressive power, while keeping animations for common types of changes easy to create thanks to predefined animation primitives. We describe the model and the associated animation editor. We also report on two user studies: the first one suggests that advanced animations are perceived as more realistic and better at focusing viewer’s attention than monolithic blending, and the second one gathers feedback about the usability of Baia’s animation editor prototype.

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