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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.
901

Design considerations for high speed clock and data recovery circuits /

Beshara, Michel, January 1900 (has links)
Thesis (M.App.Sc.) - Carleton University, 2002. / Includes bibliographical references (p. 93-95). Also available in electronic format on the Internet.
902

Development of accurate and precise methods for the determination of butyltin species in sediments using HPLC and GC separation in combination with mass spectrometric detection /

Yang, Lu, January 1900 (has links)
Thesis (Ph. D.)--Carleton University, 2004. / Includes bibliographical references (p. 152-160). Also available in electronic format on the Internet.
903

Role of TRIP6 in LPA-induced cell migration

Lai, Yun-Ju. January 2007 (has links) (PDF)
Thesis (Ph.D.)--University of Alabama at Birmingham, 2007. / Title from first page of PDF file (viewed on June 25, 2009). Includes bibliographical references.
904

Quantenchemische Studien zu ausgewählten Themen der Biochemie

Sinnecker, Sebastian. Unknown Date (has links)
Techn. Universiẗat, Diss., 2001--Berlin.
905

The regulation of G protein-coupled receptor (GPCR) signal transduction by p90 Ribosomal S6 Kinase 2 (RSK2) /

Sheffler, Douglas James. January 2006 (has links)
Thesis (Ph. D.)--Case Western Reserve University, 2006. / [School of Medicine] Department of Biochemistry. Includes bibliographical references. Available online via OhioLINK's ETD Center.
906

Photoreceptor cell fate determination and rhodopsin expression in the developing eye of Drosophila /

Birkholz, Denise A. January 2005 (has links)
Thesis (Ph.D. in Cell and Developmental Biology) -- University of Colorado at Denver and Health Sciences Center, 2005. / Typescript. Includes bibliographical references (leaves 139-155).
907

Controlabilidade exata para um sistema de equações de onda acopladas /

Pitot, João Manoel Soriano. January 2017 (has links)
Orientador: Waldemar Donizete Bastos / Banca: Andrea Cristina Prokopczyk Arita / Banca: Juliana Conceição Precioso Pereira / Banca: Carlos Alberto Raposo da Cunha / Banca: Valéria Neves Domingos Cavalcanti / Resumo: Neste trabalho estudamos o problema de controlabilidade exata na fronteira para um sistema de equações de onda acopladas em paralelo, em domínios suave por partes do plano, sob ação de controle do tipo Neuman. Utilizando o método empregado por D. L. Russell em [33] obtemos controlabilidade em tempo suficientemente grande para dados iniciais de energia finita e controle de quadrado integrável. A fim de obter tempo de controle próximo a valores ótimos, procedemos como em [21]: estendemos a solução do problema de Cauchy para tempo complexo e provamos que o operador solução associado ao problema de Cauchy é compacto e depende analiticamente do tempo num setor adequado do plano complexo. Utilizando decaimento local de energia, analiticidade e compacidade do operador solução obtemos o resultado desejado. / Abstract: In this work we study the problem of exact controllability on the boundary for a system of wave equations coupled in parallel, in piecewise smooth domains of the plane, under the action of control of Neuman type. Using the method employed by D. L. Russell in [33] we obtain controllability in time sufficiently large for initial data of finite energy and square integrable control. In order to obtain control time close to optimal values, we proceed as in [21]: we extend the solution of the Cauchy problem to complex time and we prove that the solution operator associated with the Cauchy problem is compact and depends analytically of the time in an appropriate sector of the complex plane. Using local decay of energy, analyticity and compactness of the solution operator we obtain the desired result. / Doutor
908

[en] COUPLED NUMERICAL ANALYSIS OF WATER FLOW APPLIED TO SUPERFICIAL AND UNDERGROUND HYDROLOGY / [pt] ANÁLISE NUMÉRICA ACOPLADA DE FLUXO APLICADA À HIDROLOGIA DE ÁGUAS SUPERFICIAIS E SUBTERRÂNEAS

NATALIA FARIA TAVARES 16 May 2018 (has links)
[pt] O objetivo principal do trabalho consiste na análise de problemas de fluxo sob uma ótica integrada através de simulações numéricas. Tal perspectiva vêm ganhando grande atenção por parte de profissionais da área, pois permite uma abordagem mais representativa dos processos da natureza. O programa utilizado, Mike SHE, desenvolvido pelo Instituto de Hidráulica Dinamarquês, é criado num esquema determinístico e distribuído e utiliza o método das diferenças finitas como solução. O programa simula o fluxo na superfície, canais e nas zonas saturada e não saturada. No primeiro exemplo, simulou-se a interação entre um aquífero de baixa profundidade e um rio. No segundo, verificou-se a resposta do escoamento superficial submetido a variações metereológicas e fisiográficas. Ambos casos foram validados por soluções analíticas. No terceiro, realizou-se uma simulação integrada em uma escala regional para compreensão da resposta dinâmica entre os diversos armazenamentos e através de uma ferramenta de pós- processamento, calculou-se o balanço hídrico. Por fim, avaliou-se a resposta da bacia hidrográfica do Quitite e Papagaio, localizada no maciço da Tijuca, Rio de Janeiro, mediante registros de picos de precipitação anuais. As análises integradas foram satisfatórias comparando-se a modelagens individuais. O acoplamento é explícito, permitindo a inserção de passos de tempo convenientes com cada ambiente. Por fim, a abordagem integrada permitiu que os modelos dos quatro casos fossem calibrados de acordo com parâmetros de cada ambiente hidrogeológico, aumentando a confiabilidade das simulações. / [en] This master thesis aims the analysis of flow problems under an integrated approach through numerical flow modelling. The relevance of this perspective has been increasing steadily, since it allows a more representative assessment of the nature processes. The program used, named Mike SHE, developed by the Danish Hydraulic Institute, was created in a deterministic and distributed approach solved by finite difference method. The program is comprised of modules, each representing a storage: surface, channels, vadose and saturated zone. The first analysis comprise the interaction between an aquifer of low depth and a river. In the second example, it was verified the response of flow in a surface subjected to variation of physiografic and metereological parameters. Both examples were validated with analytical solutions. In the third case, an integrated simulation was carried on in order to understand the dynamic feedback generated between the storages and through a post-processing tool the water balance was calculated. The last example, assess the response the Quitite and Papagaio basin, located in the Tijuca s massif in the city of Rio de Janeiro, over high precipitation rate. The results were satisfactory in comparison of an individual flow analysis. The coupling is explicit, allowing the input of suitable time steps for each storage. Lastly, the integrated approach allowed the model setup in the four cases to be calibrated under parameters of each storage, enhancing the reliability of them.
909

Oscillations couplées de microbulles sous champ ultrasonore et conséquences hydrodynamiques / Coupled oscillations of microbubbles under ultrasound and hydrodynamic consequences

Mekki-Berrada, Flore 16 October 2015 (has links)
Les propriétés acoustiques des bulles sont reconnues pour leur potentiel dans des applications tant biologiques que médicales. Capables de provoquer la lyse des cellules en générant des écoulements intenses, elles peuvent aussi servir d'agent de contraste en échographie.Ce manuscrit traite de la dynamique de vibration de bulles confinées entre les deux murs d'un canal microfluidique. Ces bulles exhibent une pulsation en volume aux faibles amplitudes d'excitation, à laquelle se superpose un mode de surface paramétrique aux plus fortes amplitudes. Le matériau constituant le canal étant élastique, la pulsation de la bulle confinée a pour effet de générer des ondes de Rayleigh sur les parois du canal. Grâce à ces ondes de surface, les bulles vont pouvoir se coupler les unes aux autres. Ce couplage a un effet sur les écoulements hydrodynamiques autour de ces bulles. En effet, la présence d'une bulle voisine engendre l'apparition d'un mode de translation de la bulle qui, couplé à sa pulsation en volume, conduira à la génération d'écoulements à longue portée. Ce même couplage permet aux bulles de s'auto-organiser en réseau. Afin d'étudier de manière contrôlée les effets collectifs des bulles, leur position a été fixée à l'aide de puits capillaires. Les conditions d'amplification et de synchronisation de la vibration des bulles sont recherchées en vue de créer de nouveaux méta-matériaux. / The pulsation properties of air bubbles under ultrasound have received much attention since the development of sonoporation and contrast agents. Spherical bubbles are well known to induce streaming when excited by ultrasound.We report in this manuscript the acoustic vibration of microbubbles confined between the two walls of a microfluidic channel. These bubbles exhibit a volumetric pulsation at low intensities of ultrasound, superimposed with a parametric surface mode for higher intensities of the pressure field. Because the channel walls are elastic, the bubble pulsation leads to the generation of Rayleigh waves at the channel wall interface. The bubble coupling induced by these surface waves has hydrodynamic consequences. In fact, a neighbouring bubble will create a translation mode of the bubble, in addition to its volumetric pulsation. It gives rise to a long-range mixed-mode streaming. The Rayleigh waves lead also to a self-organization of the bubbles in a network. In order to study the collective effects of these bubble networks in a controlled manner, bubble positions were fixed by capillarity on micropits. Conditions for an amplification or a synchronization of the bubble pulsations are sought in order to develop new bubble metamaterials.
910

Supplemental Educational Services in an Urban Local Education Agency: Case Study of District Implementation

January 2011 (has links)
abstract: The purpose of this study was to explore features of Supplemental Educational Services (SES) implementation at the district level. In the study beliefs, goals, and actions of district office administrators were analyzed against the backdrop of changing federal guidelines and challenges faced by SES implementers across Arizona. The case study focuses on implementation in the 2007-2008, 2008-2009, and 2009-2010 school years. The study uses the 2005 and 2009 Department of Education guidelines, survey responses from Arizona district and school implementers, as well as documents and interviews from an urban Arizona case district. The study separates the implementation activities into task areas, which are analyzed separately. Using a loose coupling perspective, the separate task areas are furthered used as coupling domains and represented in social network graphs. Results show that the case district personnel were highly focused on their primary role, maintaining district compliance with federal guidelines. The district personnel employed several changes over the case study period to centralize their control of SES operations within district. The employment and training of site level coordinators was the most impactful of the strategies. As boundary spanners, the coordinators allowed greater access to information, oversight, and influence at the site level. Despite the growing capacity and earnest efforts of the district personnel, the case district was still very far from being able to measure or assess the impact of SES on student achievement. Centralization in the scholastic task areas was relatively low, and had marginal changes over the case study period. Years into the program, there was still no avenue to accurately gauge the effectiveness. As the district personnel were chiefly concerned with compliance, they had suspended judgment on the program and focused primarily on improving their processes. / Dissertation/Thesis / Ph.D. Educational Leadership and Policy Studies 2011

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