Tesis: "Multiple reflections"

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Alvarez, Gabriel F. "Attenuation of multiple reflections in image space /". May be available electronically:, 2007. http://proquest.umi.com/login?COPT=REJTPTU1MTUmSU5UPTAmVkVSPTI=&clientId=12498.

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Zaske, Jörg Helmut. "Identification and attenuation of multiple reflections using wavefront characteristics /". [Karlsruhe] : Die Universität, 2000. http://www.ubka.uni-karlsruhe.de/cgi-bin/psgunzip/2000/physik/1/1.pdf.

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Thesis (Doctoral)--Universität Karlsruhe, 2000.
Abstract in German. Includes bibliographical references (p. 107-111). Also available via the World Wide Web. Also available via the World Wide Web. http://www.ubka.uni-karlsruhe.de/cgi-bin/psview?document=2000/physik/1 http://www.ubka.uni-karlsruhe.de/cgi-bin/psview?document=/2000/physik/2

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Verschuur, Dirk J., Deli Wang y Felix J. Herrmann. "Multi-term multiple prediction using separated reflections and diffractions combined with curvelet-based subtraction". Society of Exploration Geophysicists, 2007. http://hdl.handle.net/2429/561.

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The surface-related multiple elimination (SRME) method has proven to be successful on a large number of data cases. Most of the applications are still 2D, as the full 3D implementation is still expensive and under development. However, the earth is a 3D medium, such that 3D effects are difficult to avoid. Most of the 3D effects come from diffractive structures, whereas the specular reflections normally have less of a 3D behavior. By separating the seismic data in a specular reflecting and a diffractive part, multiple prediction can be carried out with these different subsets of the input data, resulting in several categories of predicted multiples. Because each category of predicted multiples can be subtracted from the input data with different adaptation filters, a more flexible SRME procedure is obtained. Based on some initial results from a Gulf of Mexico dataset, the potential of this approach is investigated.

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Zaske, Jörg [Verfasser]. "Identifizierung und Unterdrückung multipler Reflexionen unter Verwendung der Wellenfrontcharakteristik = Identification and attenuation of multiple reflections using wavefront characteristics / Jörg Zaske". Karlsruhe : KIT-Bibliothek, 2000. http://d-nb.info/1013933850/34.

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Ghent, Jeremy E. "A digital signal processing approach to analyze the effects of multiple reflections between highway noise barriers". Ohio : Ohio University, 2003. http://www.ohiolink.edu/etd/view.cgi?ohiou1175090494.

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Fitzgerald, Marilyn. "Are attention bias and interpretation bias reflections of a single common mechanism or multiple independent mechanisms?" University of Western Australia. School of Psychology, 2008. http://theses.library.uwa.edu.au/adt-WU2009.0052.

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There is abundant evidence of anxiety-linked threat-biased attention and anxiety-linked threat-biased interpretation (cf. Mathews & MacLeod, 1994, 2005). The present research aimed to determine whether these cognitive biases reflect a single common underlying mechanism (the Common Mechanism Account) or multiple independent underlying mechanisms (the Independent Mechanisms Account). To address this question, a battery of eight experimental tasks was developed; four tasks measured attention bias and four measured interpretation bias. Participants with different levels of trait anxiety, completed pairs of these tasks. The pattern of associations amongst all eight tasks was compared with the pattern of associations between the four tasks that measured attention bias and the pattern of associations between the four tasks that measured interpretation bias. Both Accounts predicted strong associations between the four tasks that measured attention bias, and between the four tasks that measured interpretation bias. However, the Common Mechanism Account predicted generally strong associations between all of the eight tasks, that were equivalent in strength to the associations between tasks measuring attention bias and to the associations between tasks measuring interpretation bias. In contrast, the Independent Mechanisms Account predicted weaker associations between all of the eight tasks than the associations either between the tasks measuring attention bias or between the tasks measuring interpretation bias. The obtained pattern of associations between internally reliable measures of anxiety-linked attention bias and anxiety-linked interpretation bias failed to support the Common Mechanism Account, but rather was consistent with the predictions of the Independent Mechanisms Account. Theoretical and applied implications of the results are discussed.

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Lim, Eun-Jung. "Significant Influences in the Lives of Senior Citizens: Reflections on Music Experiences during School Years and Beyond". Kent State University / OhioLINK, 2012. http://rave.ohiolink.edu/etdc/view?acc_num=kent1328371467.

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Cocher, Emmanuel. "Analyse de vitesse par migration itérative : vers une meilleure prise en compte des réflexions multiples". Thesis, Paris Sciences et Lettres (ComUE), 2017. http://www.theses.fr/2017PSLEM016/document.

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Les expériences de sismique active sont couramment utilisées pour estimer la valeur d'un modèle de vitesse de propagation desondes P dans le sous-sol. Les méthodes dites d'« analyse de vitesse par migration » ont pour but la détermination d'un macro-modèle de vitesse, lisse, et responsable de la cinématique de propagation des ondes. Dans une première étape de « migration », une image de réflectivité est obtenue à partir des données enregistrées en utilisant une première estimation du macro-modèle. Cette image dépend d’un paramètre additionnel permettant dans un second temps d’estimer la qualité du macro-modèle puis de l'améliorer. Les images de réflectivité obtenues par les techniques de migration classiques sont cependant contaminées par des artefacts, altérant la qualité de la remise à jour du macro-modèle. En particulier, elles ne prennent pas en compte les réflexions multiples, habituellement retirées des données avant traitement. Cette étape reste cependant délicate et on se prive alors de l'information supplémentaire contenue dans les multiples.Nous proposons dans cette étude une stratégie d’optimisation imbriquée en itérant l'étape de migration avant de remettre à jour le macro-modèle. La migration itérative produit des images de réflectivité satisfaisantes pour l'analyse de vitesse et s’étend naturellement aux réflexions multiples. Un désavantage de la méthode est son coût de calcul. Un pseudo-inverse de l'opérateur de modélisation est alors utilisé comme préconditionneur pour limiter le nombre d’itérations dans la boucle interne. Une autre difficulté est l'instabilité de la remise à jour du modèle de vitesse calculée pour des modèles de réflectivité successifs proches les uns des autres. Une nouvelle approche plus robustesse est proposée, valide aussi dans le cas de multiples. Son efficacité est testée sur des jeux de données synthétiques 2D
Active seismic experiments are commonly used to recover a model of the P-wave propagation velocity in the subsurface. “Migration Velocity Analysis” techniques aim at deriving a smooth background velocity model controlling the kinematics of wave propagation. First, a reflectivity image is obtained by “migration” of observed data using a first estimate of the background velocity. This image depends on an additional “subsurface-offset” parameter allowing to assess the quality of the background velocity model with a focusing criterion and to correct it. However classical migration techniques do not provide a sufficiently accurate reflectivity image, leading to inconsistent velocity updates. In particular they do not take into account multiple reflections, usually regarded as noise and removed from the data before processing. Multiple removal is however a difficult step, and additional information contained in multiples is discarded.In this thesis, we propose to determine the reflectivity model by iterative migration before subsequent velocity analysis, leading to a nested optimisation procedure. Iterative migration yields accurate reflectivity image and extends naturally to the case of multiples. One of its disadvantages is the associated increased computational cost. To limit the number of iterations in the innerloop, a preconditioner based on a pseudo-inverse of the modelling operator is introduced. Another difficulty is the instability of the velocity update obtained with very close successive reflectivity models. We propose a modified approach, valid in the presence of multiples, and discussed through applications on 2D synthetic data sets

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Costa, Filho Carlos Alberto da 1988. "Applications of independent component analysis to the attenuation of multiple reflections in seismic data = Aplicações da análise de componentes independentes à atenuação de reflexões múltiplas em dados sísmicos". [s.n.], 2013. http://repositorio.unicamp.br/jspui/handle/REPOSIP/306138.

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Orientador: Martin Tygel
Dissertação (mestrado) - Universidade Estadual de Campinas, Instituto de Matemática Estatística e Computação Cientifica
Made available in DSpace on 2018-08-22T06:13:33Z (GMT). No. of bitstreams: 1 CostaFilho_CarlosAlbertoda_M.pdf: 3131395 bytes, checksum: f8687abfc7e346fdd8e6dc40746526e8 (MD5) Previous issue date: 2013
Resumo: As reflexões de ondas sísmicas na subsuperfície terrestre podem ser colocadas em duas categorias disjuntas: reflexões primárias e múltiplas. Reflexões primárias carregam informações pontuais sobre um refletor específico, enquanto reflexões múltiplas carregam informações sobre interfaces e pontos de reflexão variados. Consequentemente é usual tentar atenuar reflexões múltiplas e trabalhar somente com reflexões primárias. Neste trabalho, a teoria de ondas acústicas é desenvolvida somente a partir da equação da onda. Um resultado que demonstra como a propagação de ondas acústicas pode ser descrita somente com uma única multiplicação por matriz é exposta. Este resultado permite que um algoritmo seja desenvolvido que, em teoria, pode ser usado para remover todas as reflexões múltiplas que refletiram na superfície pelo menos uma vez. Uma implementação prática deste algoritmo é mostrada. Por conseguinte, a teoria de análise de componentes independentes é apresentada. Suas considerações teóricas e práticas são abordadas. Finalmente, ela é usada em conjunção com o método de eliminação de múltiplas de superfície para atenuar múltiplas de quatro dados diferentes. Estes resultados são então analisados e a eficácia do método é avaliada
Abstract: The reflections of seismic waves in the subsurface of the Earth can be placed under two disjoint categories: primary and multiple reflections. Primary reflections carry pointwise information about a specific reflector while multiple reflections carry informations about various interfaces and reflection points. Consequently, it is customary to attempt to attenuate multiple reflections and work solely with primary reflections. In this work, the theory of acoustic waves is developed solely from the wave equation. A result that shows how acoustic wave propagation can be described as a single matrix multiplication is exposed. This result enables one to develop an algorithm that, in theory, can be used to remove all multiple reflections that have reflected on the surface at least once. The practical implementation of this algorithm is shown. Thereafter, the theory of independent component analysis is presented. Its theoretical and practical considerations are addressed. Finally, it is used in conjunction with the surface-related multiple elimination method to attenuate multiples in four different datasets. These results are then analyzed and the efficacy of the method is evaluated
Mestrado
Matematica Aplicada
Mestre em Matemática Aplicada

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Daniel, Isaac H. "Stitched transmission lines for wearable RF devices". Thesis, Loughborough University, 2017. https://dspace.lboro.ac.uk/2134/25581.

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With the rapid growth and use of wearable devices over the last decade, the advantages of using portable wearable devices are now been utilised for day to day activities. These wearable devices are designed to be flexible, low profile, light-weight and smoothly integrated into daily life. Wearable transmission lines are required to transport RF signals between various pieces of wearable communication equipment and to connect fabric based antennas to transmitters and receivers; the stitched transmission line is one of the hardware solutions developed to enhance the connectivity between these wearable devices. Textile manufacturing techniques that employ the use of sewing machines alongside conductive textile materials can be used to fabricate the stitched transmission line. In this thesis the feasibility of using a sewing machine in fabrication of a novel stitched transmission line for wearable devices using the idea of a braided coaxial cable have been examined. The sewing machine used is capable of a zig-zag stitch with approximate width and length within the range of 0-6 mm and 0-4mm respectively. The inner conductor and the tubular insulated layer of the stitched transmission lines were selected as RG 174, while the stitched shields were made up of copper wires and conductive threads from Light Stiches®. For shielding purpose, the structure is stitched onto a denim material with a conductive thread with the aid of a novel manufacturing technique using a standard hardware. The Scattering Parameters of the stitched transmission line were investigated with three different stitch angles 85°, 65° and 31° through simulation and experiments, with the results demonstrating that the stitched transmission line can work usefully and consistently from 0.04 to 4GHz. The extracted Scattering parameters indicated a decrease in DC loss with increased stitch angle and an increase in radiation loses, which tends to increase with increase in frequency. The proposed stitched transmission line makes a viable transmission line but a short stitch length is associated with larger losses through resistance. The DC losses observed are mainly influenced by the resistance of the conductive threads at lower frequencies while the radiation losses are influenced by the wider apertures related to the stitch angles and increase in frequency along the line. The performances of the stitched transmission line with different stitch patterns, when subjected to washing cycles and when bent through curved angles 90° and 180° were also investigated and results presented. Also, the sensitivity of the design to manufacturing tolerances was also considered. First the behaviour of the stitched transmission line with two different substrates Denim and Felt were investigated with the results indicating an insignificant increase in losses with the Denim material. Secondly, the sensitivity of the design with variations in cross section dimensions was investigated using numerical modelling techniques and the results showed that the impedance of the stitched transmission line increases when the cross sectional dimensions are decreased by 0.40mm and decreases when the cross sectional dimensions are increased by 0.40mm. Equally, repeatability of the stitched transmission line with three different stitch angles 85°, 65° and 31° were carried out. The results were seen to be consistent up to 2.5GHz, with slight deviations above that, which are mainly as a result of multiple reflections along the line resulting in loss ripples. The DC resistance of the stitched transmission line with three different stitch angles 85°, 65° and 31° corresponding to the number of stitches 60,90 and 162 were computed and a mathematical relationship was derived for computing the DC resistance of the stitch transmission line for any given number of stitches. The DC resistance computed results of 25.6Ω, 17.3Ω and 13.1Ω, for 31°, 65° and 85° stitch angles, indicated an increase in DC resistance of the stitch with decrease in stitch angle which gives rise to an increase in number of stitches. The transfer impedance of the stitched transmission line was also computed at low frequency (< 1GHz) to be ZT=(0.24+j1.09)Ω, with the result showing the effectiveness of the shield of the stitched transmission line at low frequency (< 1GHz).

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George, Lily (L M. ). "Tradition, invention, and innovation : multiple reflections of an urban marae : a thesis submitted in partial fulfilment of the requirements for the degree of Doctor of Philosophy in Social Anthropology at Massey University, Auckland, New Zealand". Massey University, 2010. http://hdl.handle.net/10179/1251.

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Marae have a place in contemporary Aotearoa New Zealand that is vital to Maori culture, as well as for all peoples of this land. Maori cultural precepts intrinsically abound with notions of the importance of marae for the transmission of that culture. Marae are places of refuge and learning where the active expression of Maori culture is most obvious. Tendrils of tradition incorporated with contemporary nuances reach out to enfold those whom these places and spaces nurture and embrace. While these ideals may not always find articulation in reality, their presence at the least provides a foundation centuries old on which to build pathways in the present and into the future. Awataha Marae is an urban marae based on Auckland?s North Shore. The history of Awataha is situated within the latest of three Renaissance Periods in which there was an upsurge in Maori culture. These Renaissance Periods were about resistance to the impositions of another culture, reclamation of part of what had been lost through colonisation, and rejuvenation of people and culture. Renaissance Period Three, in which Awataha arose, also has connections to the efforts of indigenous peoples worldwide in their endeavours to forge self determining processes for themselves, including those of conducting research that was for their benefit and purposes, rather than for those of others. Following the development of marae from pre-contact to the present day also illuminates the context within which Awataha was formed. From its beginnings as the space in front of the chief?s house where the village members gathered and where relationships were negotiated, marae today are complexes of buildings that reflect the necessities of the society that surrounds them, as well as the desire of the people to retain Maori culture in its most fundamental form. Urban marae have arisen to fulfil those desires for Maori in urban contexts, often separated from their rural homelands and for many, from their cultural heritage. Following changes in the ways in which wharenui were decorated and embellished also provides evidence of the ways in which Maori consciously innovated culture in order to endure in the new world.

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Liu, Fengyi. "High-resolution offshore reflection seismic investigation of the Stockholm Bypass tunnel". Thesis, Uppsala universitet, Institutionen för geovetenskaper, 2017. http://urn.kb.se/resolve?urn=urn:nbn:se:uu:diva-335969.

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Boat-towed high-frequency, short source and receiver spacing, reflection seismic data, 16 profiles and in total 3884 m long, were acquired in 2008 for the planning of the Stockholm Bypass multilane (3 lanes in each direction in two different tubes) underground motorway tunnel designed to ease the ever increasing car traffic on the city and neighbouring regions. The planned bypass will be about 21 km long of which 18 km will be in the form of bedrock tunnel. The planned tunnel will intersect three water passages at where the tunnel will be at around 40-50 m depth. In this study, the seismic data along two of three water passages have been processed and interpreted. Due to the relatively shallow water depth (< 10 m), the main challenge for the reflection data processing was the interferences of strong multiples from lake sediments and bedrock. After a number of tests, it was found that conventional processing methods could not attenuate multiples effectively. Therefore, an optimized workflow based on predictive deconvolution de-multiple method was developed. The new workflow proved to be effective at suppressing multiple reflections, while primary reflections as well as diffraction signals could be well preserved. After carefully attenuating the multiples in the pre-stack and post-stack domains, processing continued with time-to-depth conversion for data interpretations. To reduce uncertainty with time-to-depth conversion errors, bathymetry data available from the study area were used to match the water-sediment interface that also generated a clear reflection in the data. Bedrock surface shows strong undulations, which is typical for the Scandinavian geology from steep valleys to sometimes sub-horizontal at some parts of the water passages. Nevertheless, a dominant bedrock valley-type direction can be recognized striking in the same direction as the water passages. The planned tunnel at the nearest point is estimated to locate approximately 19 m below bedrock surface, which is important factor for the excavation planning of the tunnel and its reinforcements. The steep valley-shaped bedrock may also imply a zone of weakness, fault and/or fracture zone, where the water passages were formed and the reflection seismic data clearly depict this shape under the overlying saucer-shaped unconsolidated sediments.

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Quinn, Grzebyk Tamme. "A multiple case exploration of designers and reflection in the design space". Thesis, Wayne State University, 2015. http://pqdtopen.proquest.com/#viewpdf?dispub=3700667.

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For decades, scholars have searched for ways to more effectively teach and practice instructional design. A variety of strategies have been employed to address the ambiguity in and challenges of the field. Much of the focus in the education of instructional designers has been on teaching students how best to use the many models developed for the field (Rowling, 1992). These efforts, while meant to help the new instructional designer succeed, have often been stifled by the ever-changing landscape of what instructional designers are asked to do in their roles after graduation (Kenny, Zhang, Schwier, & Campbell, 2005). Other research centers around the ways students can fuse their new instructional design knowledge with practical activities.

While many scholars have begun to focus on alternative methods for preparing instructional designers and improving instructional design processes, instructional designers themselves have been neglected. We teach instructional designers about the profession before we have truly understood the professional. From a teaching standpoint, this approach contradicts the very foundation of instructional design education: that of recognizing that the learners/users are at the center of instructional design (Cennamo & Kalk, 2004). The purpose of this qualitative study was to examine instructional designers during design by engaging them in structured reflection as (a.) a way to better understand instructional designers in the design space and (b.) a technique for instructional designers to improve their design. Seven designers were asked to explore their thoughts, feelings, and experiences over six weeks while engaged in a design project.

This study used various data collection methods including reflection journals, interviews, and surveys. The Self-Reflection Insight Scale (SRIS) and REFLECT rubric were utilized to measure reflection abilities, and grounded theory was employed to conceptualize the data (Strauss & Corbin, 1990), while concentrating on discovery and the development of theory (Charmaz, 1983).

Results showed that each designer is unique; designers rely on distinctive designer precedents; designers perceive reflection to positively impact their design products; designers' depth of reflection waxes and wanes; and designers reflect more deeply when provided with feedback.

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Lee, Heewon. "Estimating True Object Color from a Single Image and Multiple Images". The Ohio State University, 2013. http://rave.ohiolink.edu/etdc/view?acc_num=osu1357230807.

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Beecher, Elizabeth A. "A multiple reflection cell photonic true-time delay device for phased array antennas /". The Ohio State University, 1997. http://rave.ohiolink.edu/etdc/view?acc_num=osu1487947908402612.

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Jacobs, Sean Abraham. "Nanotip silicon surface for anti-reflection and multiple exciton generation of semiconductor solar cells". Access to citation, abstract and download form provided by ProQuest Information and Learning Company; downloadable PDF file, 57 p, 2009. http://proquest.umi.com/pqdweb?did=1885519531&sid=10&Fmt=2&clientId=8331&RQT=309&VName=PQD.

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Liu, Faqi. "Surface multiple attenuation operators in the plane wave domain : theory and applications /". Digital version accessible at:, 1999. http://wwwlib.umi.com/cr/utexas/main.

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Xiao, Ting. "Pedagogical Beliefs and Practices through Guided Reflection: A Multiple-Case Study of ESL Writing Instructors". University of Cincinnati / OhioLINK, 2014. http://rave.ohiolink.edu/etdc/view?acc_num=ucin1406821489.

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Brahams, Yvonne Rae. "Development of a social studies curriculum reflecting Howard Gardner's theory of multiple intelligences". CSUSB ScholarWorks, 1997. https://scholarworks.lib.csusb.edu/etd-project/1424.

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Krol, Mark Francis 1966. "High contrast, all-optical gallium aluminum indium arsenide multiple quantum well asymmetric reflection modulator at 1.3 μm". Thesis, The University of Arizona, 1992. http://hdl.handle.net/10150/291348.

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A high contrast, low intensity GaAlInAs/AlInAs multiple quantum well asymmetric Fabry-Perot reflection modulator for operation at 1.3 μm has been demonstrated. The reflection modulator takes advantage of the large absorptive and refractive nonlinearities associated with saturating the heavy-hole exciton resonance. We achieve an on/off contrast ratio in excess of 1000:1 (30 dB) and an insertion loss of 2.2 dB at a pump intensity of 30 kW/cm², corresponding to a carrier density of 4.5 x 10¹⁷ cm⁻³ The modulator was demonstrated to have a large operating bandwidth, achieving an on/off contrast ratio of greater than 100:1 over a 5 nm optical band. The operating speed of the modulator was measured and found to approach 1 GHz.

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Gonzalez, Monica M. "Examining How Video-Elicited Reflection Mediates Teacher Candidates’ Beliefs About English Language Learners: A Multiple Case Study". Scholar Commons, 2017. http://scholarcommons.usf.edu/etd/6846.

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English Language Learners (ELLs) are students who speak a language other than English; they are the fastest growing student population in United States’ (US) public schools and will include over 17 million students by the year 2020 (NCES,2015). The dramatic increase in the ELL student population means that all mainstream classroom teachers will teach at least one ELL within their first year of graduating from a teacher preparation program. However, most US teachers hold misconceptions about ELLs and feel unprepared for ELL instruction (Coady, Harper, & de Jong, 2011). More empirical research is needed to inform teacher preparation programs on the practices that work best to prepare teachers for effective ELL instruction. Video refection and video annotation tools have become increasingly popular in teacher preparation (Calandra & Rich, 2015; Rich & Hannafin, 2009). Video annotation tools provide affordances to teacher candidates’ understanding of pedagogy and support teacher professional development (Borko et al., 2008). Still, most of the empirical research that has been done on teacher candidates’ use of video reflection reports on general education, English-speaking student learning contexts, and the research that has been done on teacher candidates use of video to reflect on ELL instruction is limited. This research aimed to fill the gap in what is known about video reflection for ELL teacher preparation, and examined how three, undergraduate, final semester teacher candidates used V- Note (a video annotation tool), and instructional coaching to reflect on instruction for elementary-aged ELLs. Sociocultural Theory was used to answer the following research questions: (a) How does video-elicited reflection shape undergraduate teacher candidates’ beliefs about ELLs and instruction for ELLs? (b) How does video-elicited reflection affirm, challenge, or reconstruct teacher candidates’ beliefs about ELLs and instruction for ELLs? Data included interviews, written reflections, and a researcher’s journal. A qualitative multiple-case study analysis (Stake, 2013) was used to generate case and cross case findings surrounding Taylor, Susan’s and Erica’s cases. Taylor’s case revealed that as Taylor used video-elicited reflection, her instruction increasingly included more language accommodations and began to include student-centered learning, video-elicited reflection reconstructed Taylor’s beliefs about using one-on-one instruction with ELLs, and collaborative coaching behaviors influenced Taylor’s instruction of ELLs more than directive coaching behaviors did. Susan’s case findings showed that video-elicited reflection challenged Susan’s misconceptions about ELLs’ language needs, Susan needed more explicit modeling to demonstrate how teachers can intentionally support ELLs’ language needs with accommodated instruction, and instructional coaching supported Susan’s understanding of ELLs’ English language proficiency levels and how these levels could be used to inform instruction. Erica’s case findings revealed that video-elicited reflection reconstructed Erica’s beliefs about collaborative learning, video-elicited reflection created a space where Erica explored using accommodations to support ELL comprehension, and video-elicited reflection developed Erica’s beliefs about language. Cross case findings reported on similarities across Taylor’s, Susan’s and Erica’s cases. The first cross case finding showed that video-elicited reflection challenged teacher candidates’ misconceptions about ELLs. The second cross case findings reported that video-elicited reflection allowed teacher candidates to develop an understating of language through appropriation, and the third cross case findings illustrated that video-elicited reflection mediated teacher candidates’ ELL pedagogical development. Findings from this research led to a discussion on the continuous use of video annotation and instructional coaching as permanent scaffolds that promote teacher candidates’ understanding of ELL pedagogy. Additionally, a discussion surrounding a cyclic model of teacher professional development that employs video-elicited reflection is shared, and the use of video-elicited reflection to facilitate teacher candidates’ participatory appropriation is discussed.

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O'Brien, Simon R. M. "Adaptive raytracing-based suppression of severe water-bottom multiples in marine seismic data". Thesis, National Library of Canada = Bibliothèque nationale du Canada, 1997. http://www.collectionscanada.ca/obj/s4/f2/dsk1/tape11/PQDD_0002/NQ42483.pdf.

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Frenander, Hannes. "High-order finite difference approximations for hyperbolic problems : multiple penalties and non-reflecting boundary conditions". Doctoral thesis, Linköpings universitet, Beräkningsmatematik, 2017. http://urn.kb.se/resolve?urn=urn:nbn:se:liu:diva-134127.

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In this thesis, we use finite difference operators with the Summation-By-Partsproperty (SBP) and a weak boundary treatment, known as SimultaneousApproximation Terms (SAT), to construct high-order accurate numerical schemes.The SBP property and the SAT’s makes the schemes provably stable. The numerical procedure is general, and can be applied to most problems, but we focus on hyperbolic problems such as the shallow water, Euler and wave equations. For a well-posed problem and a stable numerical scheme, data must be available at the boundaries of the domain. However, there are many scenarios where additional information is available inside the computational domain. In termsof well-posedness and stability, the additional information is redundant, but it can still be used to improve the performance of the numerical scheme. As a first contribution, we introduce a procedure for implementing additional data using SAT’s; we call the procedure the Multiple Penalty Technique (MPT). A stable and accurate scheme augmented with the MPT remains stable and accurate. Moreover, the MPT introduces free parameters that can be used to increase the accuracy, construct absorbing boundary layers, increase the rate of convergence and control the error growth in time. To model infinite physical domains, one need transparent artificial boundary conditions, often referred to as Non-Reflecting Boundary Conditions (NRBC). In general, constructing and implementing such boundary conditions is a difficult task that often requires various approximations of the frequency and range of incident angles of the incoming waves. In the second contribution of this thesis,we show how to construct NRBC’s by using SBP operators in time. In the final contribution of this thesis, we investigate long time error bounds for the wave equation on second order form. Upper bounds for the spatial and temporal derivatives of the error can be obtained, but not for the actual error. The theoretical results indicate that the error grows linearly in time. However, the numerical experiments show that the error is in fact bounded, and consequently that the derived error bounds are probably suboptimal.

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Davis, Elizabeth Marie. "A Multiple Case Study of How Semester-long Education Abroad Students Come to Know Themselves While Studying Abroad". Kent State University / OhioLINK, 2019. http://rave.ohiolink.edu/etdc/view?acc_num=kent155376281073727.

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Cardoso, Claudio Guerra. "Eliminação de reflexões multiplas por empilhamento tipo Kirchhoff em configuração de afastamento comum". [s.n.], 1999. http://repositorio.unicamp.br/jspui/handle/REPOSIP/262946.

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Orientadores: Martin Tygel, Eduardo Filpo Ferreira da Silva
Dissertação (mestrado) - Universidade Estadual de Campinas, Faculdade de Engenharia Mecanica
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Resumo: Atualmente, cerca de 90% das reservas brasileiras de óleo localizam-se nas porções submersas das bacias sedimentares costeiras. Nessas bacias, a sísmica de reflexão é uma das principais ferramentas de que dispõe o profissional de exploração e de desenvolvimento de campos de petróleo. Como a interpretação dos dados sísmicos considera somente as reflexões primárias, é necessário que estes estejam livres de ruídos, particularmente, da reflexão múltipla do fundo do mar, que é o ruído mais danoso em dados marítimos. A presente dissertação descreve um método novo de eliminação de múltipla do fundo do mar de 1ª ordem em configuração de afastamento fonte - receptor comum, por empilhamento Kirchhoff, mostrando exemplos numéricos de aplicação do mesmo em dados sintéticos. Num desses exemplos, no qual concorrem a múltipla e uma reflexão primária - que poderia advir de um refletor de interesse - após a eliminação da múltipla, as diferenças nas amplitudes da primária, quando comparadas com as amplitudes sem a interferência da múltipla, não ultrapassam 5%. Dessa forma, o método, por preservar as amplitudes das primárias após a eliminação da múltipla, se configura como muito adequado à geofísica de reservatórios
Abstract: At present, about 90% of Brazilian oil reserves are located in offshore sedimentary basins. In these basins, reflection seismic is one of the most important tools in exploration and field development. As seismic data interpretation only deals with primary reflections, is important to have noise-free, amplitude preserved primaries. The most harmful noise in marine data is the first-order, sea-bottom multiple reflection. This dissertation describes a new method for first order, sea-bottom, multiple elimination by means of a Kirchhoff - type stacking, in common offset configuration, showing its application to synthetic seismic data. In one of the examples, in which the multiple and a primary reflection interfere, the differences between amplitudes of primary reflection after application of the method and primary computed with no such interference are smaller than 5%. Due to the primaries amplitude-preserving property, this method provides a very reliable image to reservoir geophysics, such as amplitude versus offset analysis (AVO) and seismic attribute determination
Mestrado
Mestre em Engenharia de Petróleo

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Obr, Jakub. "Pokročilá simulace a vizualizace kapaliny". Master's thesis, Vysoké učení technické v Brně. Fakulta informačních technologií, 2011. http://www.nusl.cz/ntk/nusl-237084.

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This thesis concentrates on physically based simulation of fluids followed by its photorealistic visualization. It describes one form of Smooth Particle Hydrodynamics methods for viscoelastic fluid simulation and includes its extension for multiple interacting fluids. It also deals with SPH boundary problem and investigates its solution by fixed boundary particles. For visualization of fluids there is a method of Ray Tracing described in detail and it's extended with light absorption in transparent materials. In connection with this method there is also discussed a problem of infinite total reflections and some solution techniques are offered. To extract the surface of the fluid there is used a Marching cubes method and its discussed in terms of Ray Tracing.

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Law, Masa. "The Development and Modelling of a Novel Clamp-on Ultrasonic-Thermal and Ultrasonic Multiple Reflection Flowmeter for Liquid Applications". Thesis, Cranfield University, 1994. http://dspace.lib.cranfield.ac.uk/handle/1826/4596.

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The development of a novel combined "ultrasonic/thermal" with "ultrasonic multiple reflections" clamp-on meter for measuring a wide flowrate range of clean liquids in small diameter pipes is presented. Current existing flowmeters based on ultrasound cannot measure very low flowrates for single phase liquids. The ultrasonic/thermal technique can measure single phase flows in the range 0 to 0.6 m s' in pipes with diameters as small as 15 mm. It can also detect and measure reverse flows. The minimum flowrate for the ultrasonic multiple reflection technique is about 0.55 m s', and theoretically, the measurement accuracy increases with increased flow velocity. The ultrasonic/thermal technique is based on a heating element and transducer pair(s) which can be clamped to the outside of a pipe. With the heaters switched on, the changes in the temperature of the pipe and the liquid inside it result in changes in transit time. The flowrate can be therefore estimated by either the transit time difference across the pipe at the two symmetric locations with respect to the heater centre, or at one location with a heater off/on comparison. The latter approach was felt to be the promising for low flowrate measurements and therefore selected for the numerical and the experimental investigations. The multiple reflection technique was developed based on the conventional transit time flowmeter. This technique extended the measuring range of the flowmeter and provided cross calibration for the ultrasonic/thermal technique. A computer model was developed for the ultrasonic multiple reflection technique. However, there was insufficient experimental data to confirm the computer prediction. Results from computational fluid dynamics (CFD) analysis of the meter are presented. For vertical pipes an axisymmetric model was used, but the presence of buoyancy forces required the use of a 3-D model for horizontal pipes. Temperature and velocity distributions and ultrasonic transit times have been computed and are presented. In order to overcome the problem of mode conversion and refraction at the pipe wall/transducer mounting interface, novel transducers and mounting blocks are presented. A prototype heater and ultrasonic transducer system together with electronics for signal generation and transit time measurement have been designed and constructed. A hydraulic system has also been designed and constructed for testing the developed clamp-on flowmeter. Experimental results from this apparatus are presented and compared with the CFD predictions, and a technique for compensating for variations in inlet temperature is described. The full scale difference between the computed values and experimental results of the meter for low flowrate measurement was about 3.5%.

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Hornung, Christine [Verfasser]. "High-Resolution Experiments with the Multiple-Reflection Time-Of-Flight Mass Spectrometer at the Fragment Separator FRS / Christine Hornung". Gießen : Universitätsbibliothek, 2018. http://d-nb.info/1173086870/34.

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Jones, Phyllis. "Making meaning with teachers of pupils with profound and multiple learning difficulties : reflecting on identity and knowledge". Thesis, Northumbria University, 2002. http://nrl.northumbria.ac.uk/2391/.

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This thesis analyses a complex process of meaning making. It centres upon the meaning making of a group of fourteen teachers who teach pupils with profound and multiple learning disabilities (pmld). The nature of the meaning making changed as the research progressed. It moved from my meaning making of the teachers to my meaning making with the teachers. Integral to this was a process of personal meaning making and critical self reflection. The qualitative paradigm of research methodology offered a framework that informed my methodological decisions. The influence of symbolic interaction, critical theory and grounded theory was instrumental in the initial stages of the research process. Latterly, the role of social construction became important in my meaning making. The contribution of questionnaires, individual and group interviews to the process of meaning making, in the context of this work while necessary, has proved to be problematic, particularly in relation to the organic nature of the research, my personal role in it, and the role of ethics. I argue for an ongoing ethical debate within the research that develops as the research progresses and changes. The research has highlighted the integral role of teacher identity and notions of specialist knowledge in the development, sustenance and challenging of the teachers' understandings about the pupils they teach who have pmld. Inherent in these understandings are the personal experiences the teachers have encountered throughout their lives. These understandings have been analysed and the dominant influences of particular theories and models of disability are made explicit. The influence of labelling, categorising and the professional discourse has also been shown to be an integral element of the study. As a teacher educator, I have gained some insights which may improve the support I offer to teachers in their professional development. These insights relate to the importance of acknowledging the role of teacher identity, and engaging teachers in a process of analysis that encourages them to appreciate the impact of teacher identity on their understandings. An important element of this would be reflection on their personal experiences. In relation to specialist knowledge, a critical analysis of pedagogy is argued for: a process that engages teachers in wider notions of pedagogy for all learners, but which supports them in translating this pedagogy to effective teaching and learning for pupils with pmld.

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Ebert, Jens [Verfasser]. "Mass measurements of 238U-projectile fragments for the first time with a Multiple-Reflection Time-Of-Flight Mass Spectrometer / Jens Ebert". Gießen : Universitätsbibliothek, 2016. http://d-nb.info/1106853083/34.

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Jesch, Christian [Verfasser]. "The multiple-reflection time-of-flight isobar separator for TITAN and direct mass measurements at the FRS Ion Catcher / Christian Jesch". Gießen : Universitätsbibliothek, 2016. http://d-nb.info/1102854034/34.

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Lang, Johannes Sebastian [Verfasser]. "Development of a mobile high-resolution Multiple-Reflection Time-of-Flight Mass Spectrometer for in-situ life science application / Johannes Sebastian Lang". Gießen : Universitätsbibliothek, 2017. http://d-nb.info/1128593807/34.

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Nguyen, Tran. "Optical measurement of shape and deformation fields on challenging surfaces". Thesis, Loughborough University, 2012. https://dspace.lboro.ac.uk/2134/10551.

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A multiple-sensor optical shape measurement system (SMS) based on the principle of white-light fringe projection has been developed and commercialised by Loughborough University and Phase Vision Ltd for over 10 years. The use of the temporal phase unwrapping technique allows precise and dense shape measurements of complex surfaces; and the photogrammetry-based calibration technique offers the ability to calibrate multiple sensors simultaneously in order to achieve 360° measurement coverage. Nevertheless, to enhance the applicability of the SMS in industrial environments, further developments are needed (i) to improve the calibration speed for quicker deployment, (ii) to broaden the application range from shape measurement to deformation field measurement, and (iii) to tackle practically-challenging surfaces of which specular components may disrupt the acquired data and result in spurious measurements. The calibration process typically requires manual positioning of an artefact (i.e., reference object) at many locations within the view of the sensors. This is not only timeconsuming but also complicated for an operator with average knowledge of metrology. This thesis introduces an automated artefact positioning system which enables automatic and optimised distribution of the artefacts, automatic prediction of their whereabouts to increase the artefact detection speed and robustness, and thereby greater overall calibration performance. This thesis also describes a novel technique that integrates the digital image correlation (DIC) technique into the present fringe projection SMS for the purpose of simultaneous shape and deformation field measurement. This combined technique offers three key advantages: (a) the ability to deal with geometrical discontinuities which are commonly present on mechanical surfaces and currently challenging to most deformation measurement methods, (b) the ability to measure 3D displacement fields with a basic single-camera single-projector SMS with no additional hardware components, and (c) the simple implementation on a multiple-sensor hardware platform to achieve complete coverage of large-scale and complex samples, with the resulting displacement fields automatically lying in a single global coordinate system. A displacement measurement accuracy of ≃ 1/12,000 of the measurement volume, which is comparable to that of an industry-standard DIC system, has been achieved. The applications of this novel technique to several structural tests of aircraft wing panels on-site at the research centre of Airbus UK in Filton are also presented. Mechanical components with shiny surface finish and complex geometry may introduce another challenge to present fringe projection techniques. In certain circumstances, multiple reflections of the projected fringes on an object surface may cause ambiguity in the phase estimation process and result in incorrect coordinate measurements. This thesis presents a new technique which adopts a Fourier domain ranging (FDR) method to correctly identifying multiple phase signals and enables unambiguous triangulation for a measured coordinate. Experiments of the new FDR technique on various types of surfaces have shown promising results as compared to the traditional phase unwrapping techniques.

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Lippert, Wayne [Verfasser]. "Further development and application of a mobile multiple-reflection time-of-flight mass spectrometer for analytical high-resolution tandem mass spectrometry / Wayne Lippert". Gießen : Universitätsbibliothek, 2016. http://d-nb.info/1114053686/34.

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Dudeck, Barbara Jean. "Development of a life science curriculum for kindergarten and first grade reflecting the theories of multiple intelligence and brain-based learning". CSUSB ScholarWorks, 2001. https://scholarworks.lib.csusb.edu/etd-project/1897.

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Assos, Charalambos. "Organic ligand complexation reactions on aluminium-bearing mineral surfaces studied via in-situ multiple internal reflection infrared spectroscopy, adsorption experiments, and surface complexation modelling". Thesis, University of Manchester, 2010. https://www.research.manchester.ac.uk/portal/en/theses/organic-ligand-complexation-reactions-on-aluminiumbearing-mineral-surfaces-studied-via-insitu-multiple-internal-reflection-infrared-spectroscopy-adsorption-experiments-and-surface-complexation-modelling(43f53df4-8d74-4237-a67e-9b86f2dee9ac).html.

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Organic ligand complexation reactions at the mineral-water interface play an important role in several environmental and geochemical processes such as adsorption, dissolution, precipitation, pollutant transport, nutrient cycling, and colloidal stability. Although organic ligand surface complexation reactions have been extensively studied, a molecular level understanding regarding the mechanisms underlying the adsorption of such compounds is still limited. The purpose of the current study was to investigate the interactions between some common naturally occurring organic ligands and a common aluminosilicate clay mineral, kaolinite, using a combination of macroscopic and microscopic experimental methods. Molecular level information regarding the structure and binding mode of adsorbed species was obtained using in situ MIR-FTIR spectroscopy. Other experimental techniques including adsorption experiments, surface titrations, and surface complexation modelling were also employed in order to quantify and describe the macroscopic adsorption properties of the organic ligands examined. Three low molecular weight organic acids (oxalic, salicylic, and phthalic acid) and humic acid were chosen as representative organic ligands. Spectroscopic evidence revealed that low molecular weight organic acids are able to form both inner and outer sphere complexes on kaolinite, and the relative concentrations of these surface complexes varies with solution chemistry. Inner sphere coordination modes inferred are a mononuclear bidentate for oxalate (five-membered chelate ring) and phthalate (seven-membered chelate ring); and a mononuclear monodenate (six-membered pseudochelate ring) for salicylic acid. Similar coordination modes were shown to form on simpler mineral (hyrd)oxides. Elucidation of the coordination chemistry of these ligands can provide insights into the dissolution mechanisms of silicate minerals In contrast to low molecular weight organic acids, there was no evidence of inner sphere complexation by humic acid acids on kaolinite or gibbsite. The combined spectroscopic and macroscopic adsorption results suggest that cation bridging and van der Waals interactions are the two most probable mechanisms for the adsorption of humic acid by these mineral substrates. This finding casts doubts over the use of low molecular weight organic acids as humic acid analogs.

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Ayet, San Andres Samuel [Verfasser]. "Developments for multiple-reflection time-of-flight mass spectrometers and their application to high-resolution accurate mass measurements of short-lived exotic nuclei / Samuel Ayet San Andres". Gießen : Universitätsbibliothek, 2018. http://d-nb.info/1171704631/34.

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Gérardin, Benoit. "Manipulation et contrôle d'ondes élastiques guidées en milieux complexes". Thesis, Sorbonne Paris Cité, 2016. http://www.theses.fr/2016USPCC230/document.

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Quelle que soit la nature des ondes utilisées et des milieux traversés, le contrôle de la propagation ondes est d'un intérêt majeur pour de nombreuses applications. D'une part, la complexité du milieu peut être exploitée en exerçant un contrôle cohérent du front d’onde incident. D'autre part, on peut forcer une onde à se propager suivant un chemin désiré en concevant soi-même le milieu de propagation. Dans cette thèse, nous étudions ces deux aspects à partir d'expériences ultrasons-laser mettant en jeu la propagation d'ondes de Lamb dans des plaques.La propagation des ondes à travers un milieu diffusant est tout d’abord étudiée à partir de sa matrice de diffusion. Une prédiction théorique importante est l’existence de canaux de propagation totalement ouverts ou fermés. Une première partie de ces travaux consiste à démontrer expérimentalement ce résultat en mettant en évidence la possibilité de transmettre totalement une onde à travers un milieu désordonné. Dans un second temps, la mesure d’une matrice des temps de vol nous permet d’étudier ces canaux dans le domaine temporel. Ceux-ci donnent lieu à des paquets d’onde dont la cohérence spatiale et temporelle est conservée tout au long de leur propagation dans le milieu.Le second volet de cette thèse consiste à tirer profit des phénomènes de réflexion et réfraction négative afin de contrôler la propagation des ondes de Lamb. D’une part, la réflexion négative est mise à profit pour réaliser une conjugaison de phase passive des ondes de Lamb. D’autre part, le concept des milieux complémentaires est exploré afin d’annuler la diffraction des ondes et ainsi camoufler certaines zones du milieu de propagation
Whatever their nature or the propagation medium, controlling the propagation of waves is of fundamental interest for many applications. On the one hand, one can tame wave-fields in order to take advantage of the complexity of the medium. On the other hand, one can force waves along desired paths through a careful design of manmade materials. In this thesis, we study those two aspects on the basis of laser-ultrasonic experiments involving the propagation of Lamb waves in elastic plates.The control of wave propagation through complex systems is first investigated by means of the scattering matrix approach. In diffusive media, theorists have demonstrated the existence of propagation channels either closed or open through which the wave can travel. The first part of this work present a direct experimental evidence of this result as well as the ability to fully transmit a wave through a disordered medium. In a second part, the measurement of the time-delay matrix allows the study of such channels in the time domain. They are shown to give rise to particle-like wave packets that remain focused in time and space throughout their trajectory in the medium.The second part of this thesis consists in studying the concepts of negative reflection and refraction for the manipulation of Lamb wave propagation. On the one hand, negative reflection is taken advantage of to perform a passive phase conjugation of Lamb waves. On the other hand, the notion of complementary media is investigated in order to cancel the diffraction of waves and cloak some areas of the plate

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Ouattara, Yélakan. "Développement d'une approche radar pour l'étude des réflexions sur les bâtiments et l'analyse des irrégularités de façade". Phd thesis, Université Paris-Est, 2010. http://tel.archives-ouvertes.fr/tel-00598279.

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Cette thèse s'inscrit dans la lignée des travaux sur la prédiction du champ électromagnétique réfléchi par les bâtiments en milieu urbain. Nous avons développé une méthode de prédiction basée sur la Surface Équivalente Radar (SER) pour le traitement spécifique des bâtiments situés en zone lointaine. Contrairement aux méthodes classiques de lancer et le tracé de rayons où les réflexions sont traitées rayons par rayons, notre approche utilise la SER global d'un ensemble de bâtiments pour décrire la réflectivité des scènes. Le champ électrique est ensuite reconstruit au point de réception à partir de cette SER. La méthode de calcul est analytique et essentiellement basée sur la combinaison de l'optique géométrique (OG) et du calcul de l'intégrale de Kirchhoff-Huygens. Les interactions multiples de l'onde entre les bâtiments sont également prises en compte dans le modèle proposé. Les résultats obtenus en termes de précision de prédiction dans les directions spéculaires et non-spéculaires sont très satisfaisants. Les temps de calcul n'excédent pas 5 secondes pour les scénarios les plus complexes simulés ; ils permettent ainsi de réduire les temps de calcul et de surmonter les contraintes en place mémoire lors de l'étude d'une scène urbaine. Dans une seconde étude, l'influence des irrégularités des façades sur le champ électromagnétique diffracté a été évaluée. Nous utilisons la méthode des moments (MoM) bidimensionnelles (2D) pour résoudre de façon rigoureuse le problème de diffraction lié à trois types de façades : façade plane, façade corruguée et façade avec des balcons. A partir de la distribution du champ diffracté en zone proche et des diagrammes de rayonnement des façades en zone lointaine, nous décrivons les différents mécanismes de diffraction qui s'y produisent et les directions de réflexion prépondérantes sont données pour chacune des façades. Les travaux présentés dans cette thèse s'inscrivent dans le cadre du projet ANR OP2H (Outil de Prédiction par navigation Hiérarchique et Homogénéisation de matériaux)

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Abbas, Qaisar. "Weak Boundary and Interface Procedures for Wave and Flow Problems". Doctoral thesis, Uppsala universitet, Avdelningen för teknisk databehandling, 2011. http://urn.kb.se/resolve?urn=urn:nbn:se:uu:diva-159440.

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In this thesis, we have analyzed the accuracy and stability aspects of weak boundary and interface conditions (WBCs) for high order finite difference methods on Summations-By-Parts (SBP) form. The numerical technique has been applied to wave propagation and flow problems. The advantage of WBCs over strong boundary conditions is that stability of the numerical scheme can be proven. The boundary procedures in the advection-diffusion equation for a boundary layer problem is analyzed. By performing Navier-Stokes calculations, it is shown that most of the conclusions from the model problem carries over to the fully nonlinear case. The work was complemented to include the new idea of using WBCs on multiple grid points in a region, where the data is known, instead of at a single point. It was shown that we can achieve high accuracy, an increased rate of convergence to steady-state and non-reflecting boundary conditions by using this approach. Using the SBP technique and WBCs, we have worked out how to construct conservative and energy stable hybrid schemes for shocks using two different approaches. In the first method, we combine a high order finite difference scheme with a second order MUSCL scheme. In the second method, a procedure to locally change the order of accuracy of the finite difference schemes is developed. The main purpose is to obtain a higher order accurate scheme in smooth regions and a low order non-oscillatory scheme in the vicinity of shocks. Furthermore, we have analyzed the energy stability of the MUSCL scheme, by reformulating the scheme in the framework of SBP and artificial dissipation operators. It was found that many of the standard slope limiters in the MUSCL scheme do not lead to a negative semi-definite dissipation matrix, as required to get pointwise stability. Finally, high order simulations of shock diffracting over a convex wall with two facets were performed. The numerical study is done for a range of Reynolds numbers. By monitoring the velocities at the solid wall, it was shown that the computations were resolved in the boundary layer. Schlieren images from the computational results were obtained which displayed new interesting flow features.

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Bonnard, Anne. "Interpréter pour (inter)agir et apprendre : la course d'orientation en Education physique et sportive au Baccalauréat". Thesis, Besançon, 2012. http://www.theses.fr/2012BESA1028/document.

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Cette étude propose une approche centrée sur l’activité de l’élève telle que définie et expériencée en cours d’Education Physique et Sportive. Il s’agit d’accéder à ce qui fait sens pour lui/elle lorsque confronté à une situation de résolution de problème, étant entendu que la démarche menée est inductive, participante et internaliste. Le contexte de l’étude se place dans un cycle complet de Course d’Orientation (T = 16h de pratique effective ; 8 séances) mené par un enseignant expert de l’approche réflexive et de l’APSA, auprès d’une classe optionnaire de 19 élèves (âge moyen 17ans ½). Trois études sont menées afin de caractériser le fonctionnement des élèves confrontés à l’épreuve de Baccalauréat et à sa préparation. La première étude porte sur l’analyse de la performance à différents moments du cycle. La seconde étude porte sur les interactions entre profils moteurs, verbaux et réflexifs des élèves à partir des traces écrites de leur activité. La troisième étude s’intéresse, à partir d’un test ante/post cycle inspiré de la théorie des intelligences multiples de Gardner, à cerner l’évolution des capacités déclarées par les élèves. Les résultats montrent que les élèves voient leurs profils évoluer avec une réussite variable au cours du cycle ; ces profils s’expriment en contexte en fonction des situations d’apprentissage, des ressources mobilisées et de l’interprétation des relations carte/milieu naturel. Un suivi de cas permet d’individualiser les résultats qui viennent à la fois questionner la manière dont est abordée l’APSA Course d’Orientation et les stratégies complexes déployées par les élèves
This study focuses on the student’s activity as defined and experienced in Physical Education. The target was to reach what makes sense for him/her when confronted with a problem solving task. The method used an inductive, participative and internalist approach. The study’s context was an optional full learning cycle of Orienteering (T= 16 hours duration; 8 sequences; n = 19 students 17 and half years old) taught by an expert teacher on critical thinking approach and on this sport practice. Three studies are expected to characterize the student functioning when confronted with the Baccalaureat examination and preparation. The first study layed on the analyzis of the performance at different moments of the learning. The second study was on the interactions between student motor, verbal and reflective profiles from the written reports of their activity. The third study was based on the pre/post test inspired from Gardner’ theory of the multiple intelligences: it helped describing the evolution of the declared capabilities of the students. Results showed that student profiles evolve according to a variable success all along the learning cycle; these profiles express within the situated context according to the learning tasks, the mobilized resources and the interpretation of the relationship between the map and the effective natural environment. A case study allowed individualizing the observations so as to question at a time the way Orienteering has to be taught and the complex strategies used by students

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Chang, Hui. "Prediction of seismic parameters from primary and multiple reflections /". 2008. http://proquest.umi.com/pqdweb?did=1507553301&sid=8&Fmt=2&clientId=10361&RQT=309&VName=PQD.

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Sathorn, Chankhrit. "Effectiveness and efficiency: systematic reflections on single- and multiple-visit root canal treatment". 2008. http://repository.unimelb.edu.au/10187/3128.

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Single-visit root canal treatment was first documented in 1887. The controversy and debate within the dental community has been ongoing for over a century without resolution. The concept of evidence-based health practice has provided a structure on which the clinically-relevant questions in this debate can be dealt with systematically. When clinicians are faced with choices of which treatment regimen should be offered to patients, the central issues that should be considered are effectiveness, complications, patient/operator preference/satisfaction, and cost. Systematic review and meta-analysis techniques were used to reach definitive conclusions where high quality primary studies are available. The issue of satisfaction was studied using a quality of life concept, while the issue of cost was addressed by an economic evaluation (cost-minimization analysis). Treatment effectiveness and complications of single- and multiple-visit approach were similar. Patients overwhelmingly preferred single- over multiple-visit treatment with high satisfaction scores for both regimens. Australian endodontists were reluctant to embrace single-visit root canal treatment. Single-visit root canal treatment costs society less than multiple-visit treatment. On balance single-visit treatment offers substantial advantages with no identified adverse effects.

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Wang, Ming-Jen y 王明仁. "U-shaped Optical Fiber Biosensor Based on Multiple Total Internal Reflections in Heterodyne Interferometry". Thesis, 2007. http://ndltd.ncl.edu.tw/handle/49154433200222454881.

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碩士
清雲科技大學
電子工程研究所
94
In this research, an optical fiber biosensor based on multiple total internal reflections in heterodyne interferometry is proposed. The sensor is made of a long U-shaped multimode optical fiber which cladding is removed from the sensing portion of the fiber. With the fiber biosensor the phase shift difference due to the multiple total internal reflections (MTIR) effect between the P and S-polarizations is measured by using heterodyne interferometry. Substituting the phase shift difference into Fresnel’s equations, the refractive index for the tested medium can be calculated. It is clear that the sensitivity can reach 6300 (degree/RIU) in the range of from 1.33 to 1.365 and the resolution of the sensor can reach refractive index unit (RIU). The optical fiber biosensor could be valuable for chemical, biological and biochemical sensing. It has some merits, such as, high resolution and stability, small size and real-time measurement.

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Huang, Chun-Wei y 黃軍瑋. "Reflective Type New Biosensor Based on Multiple Attenuated-Total Internal Reflections in Heterodyne Interferometry". Thesis, 2009. http://ndltd.ncl.edu.tw/handle/87987722301262585793.

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碩士
清雲科技大學
電子工程系所
97
In the paper, a new biosensor based on multiple attenuated total reflections in heterodyne interferometry is presented. The biosensor is made of reflective elongated prism, which shorter side surface is coated with 2-nm Ti film and 45.5-nm Au film, but the other side surface is not coated with any metal film. As a heterodyne light is passed through the reflective elongated prim, it will induce the phase shift difference between the S- and P-polarization lights due to the attenuated total reflections (ATRs) effect. Substituting the phase shift difference into Fresnel’s equations, the related parameters of the tested medium can be calculated. The resolution of the sensor can reach 1.155×10-6 refractive index unit (RIU). The sensor has some merits, such as, small volume, high resolution, high sensitivity, and stability etc.

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Li, Syue-Ying y 李學瑩. "Study on a Transmission-type Biosensor Based on Multiple Total Internal Reflections in Heterodyne Interferometry". Thesis, 2017. http://ndltd.ncl.edu.tw/handle/kd582z.

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碩士
健行科技大學
電子工程系碩士班
105
In the paper, a transmission-type biosensor based on multiple attenuated total reflections in heterodyne interferometry is presented. The biosensor is made of an elongated prism, the height of the reflective elongated prism in the sensing region is D, D=0.6cm. The length of the sensor is L, L=11.6cm, index of outside (n3) is 1.33~1.37. The outside of elongated prism that coated with the two metal film of Ti and Au. As a heterodyne light is passed through the reflective elongated prim, it will induce the phase shift difference between the S- and P-polarization lights due to the attenuated total reflections (ATRs) effect. Substituting the phase shift difference into Fresnel’s equations, the related parameters of the tested medium can be calculated. The biosensor has some merits, such as, small volume, high resolution, high sensitivity, and stability, etc.

47

Chen, Wei-Wu y 陳威宇. "A novel method for measuring small displacement by use of multiple total reflections in heterodyne". Thesis, 2005. http://ndltd.ncl.edu.tw/handle/78067242533422137459.

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Resumen

碩士
國立中央大學
光電科學研究所
93
A novel method for measuring small displacement by use of multiple internal reflections in heterodyne interferometry is proposed. In the dissertation, we can achieve a small displacement only by measuring the variation in phase difference between s- and p-polarization states at the total-internal reflection effect. To improve the sensitivity we increase the number of total internal reflections by using a parallelogram prism. The displacement resolution of the method is batter than 0.4nm. Its measurement range can reach. 　　The method has some merits, for example, a simple optical setup, high resolution, high sensitivity, rapid measurement, and high stability and so on. Its feasibility is demonstrated.

48

Hong, Wei-Jyun y 洪瑋駿. "Study on a Cylindrical Optical Fiber Sensor Based on Multiple Total Internal Reflections in Heterodyne Interferometry". Thesis, 2017. http://ndltd.ncl.edu.tw/handle/5uk82a.

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Resumen

碩士
健行科技大學
電子工程系碩士班
105
In this paper, a new type biosensor based on attenuated total reflection (ATR) in heterodyne interferometry (HI) is presented. As a heterodyne optical source is launched into the biosensor at a suitable incident angle, we can obtain the phase difference between s- and p- polarizations at the output of the optical fiber sensor. When a laser light source enters a fiber, the internal refractive index of the fiber is affected by the metal film, The sensitivity of the sensor can reach 2.675

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sheng, Chang-chi y 張繼生. "The study of optical fiber biosensor based on the multiple total internal reflections in heterodyne interferometry". Thesis, 2007. http://ndltd.ncl.edu.tw/handle/47359196682888156676.

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50

Shih, You-Song y 石祐菘. "A Three-Shock Theoretical Analysis of Multiple Solutions of Steady Mach Reflections in Perfect Triatomic Gases". Thesis, 2004. http://ndltd.ncl.edu.tw/handle/9fpcw4.

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Tesis sobre el tema "Multiple reflections"

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