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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.
461

網際網路與電視匯流之關鍵成功因素探討

張育誠, Sherman Chang Unknown Date (has links)
網際網路與電視匯流之關鍵成功因素探討 《中文摘要》 數位狂潮衝刷媒介生態沃土,網路、電視與電信三大領域,在技術、服務與通路上匯流出競爭與互補的大媒體潮。網電合一扮演不同而又多重的角色,面對科技、法規、市場與管理上的競合,形成網路、電視、電信產業「三網合一」(Triple Play)的「網電匯流」閱聽趨勢。數位內容產業具有「一次生產、多元加工、多頻傳輸、多工服務」特性,網路的數位互動、超文本、虛擬化,成就了寬頻影音典範。一個簡單的問題是:網路電視(WebsTV)能否搬到數位電視(Digital TV)上? 本論文探究「網電匯流」與「關鍵成功因素」二大主題,以文獻探討與深度訪談設計,訪問中華電信M.O.D.(Multimedia On Demand, M.O.D.)、數位聯合電信公司SeedNet D.F.C.(Digital Family Center, D.F.C.)、東森有線電視機上盒S.T.B.(Set-top box)與網路電視等多系統經營業者(Multiple System Operators, MSO)共八家公司九位專家,針對網路與電視匯流的關鍵成功因素發表意見。研究者並以自己在網路公司參與電視台數位化的親身觀察,探討如何融合具寬頻網站與數位電視製播特色的關鍵成功因素。 研究發現網路與電視匯流的「新媒介」(New Media)必須在:匯流目標策略、企業價值鍊、殺手級內容、數位匯流科技、市場績效等五個要素上,豐富顧客實體和虛擬經驗的平台,以使用者為中心、客制化互動的社群思維,去拓展數位電視市場,才能在傳播新世代,為大眾開拓新閱聽時空。 / The Key Successful Factors of Converging the Internet and Television The digital mega-trend has caused enormous impact in the world of mass media.In three major fields: Internet, television and telecommunications, the combination of internet and television have created a new wave of competition and co-operation in areas such as technology, regulation, marketing and management. This will lead to the triple play of internet, television and telecommunications that will set the new trend. Digital industry has the unique feature of 「Once producing、MultiProcessing、Multichannel Transmission、Multiworkers service」, and other characteristics such as internet interaction and Hypertext、Virtual will become the M.O.D.el for broadband entertainment. But, here raises one simple question:“Can WebsTV being duplicated onto the Digital TV”? This thesis will discuss into depth the two major topics of “Convergence”and “Key Successful Factors”using literature review and interviews with 9 experts from: M.O.D of ChungHwa Telecom, Seednet D.F.C., ETTV S.T.B., and Multiple System Operators of Cable TV etc. Empirical experiences gained from working in relevant industry will also be used to discuss the success factors in converging broadband website and digital television. Research discovered that the“New Media”which converging the internet and television will need to fulfill five major aspects in: converging target strategy, enterprise value chain, killer level content, digital converging technology and market performance. In order to create a user-friendly environment and platform, that will provide effective interaction between the user and supplier. By doing so, it will give all users a whole new experience in the world of digital entertainment.
462

Développements statistiques et algorithmiques pour l'analyse des cancers du sein de type triple négatif

Rigaill, Guillem 17 November 2010 (has links) (PDF)
Dans le monde, le cancer du sein est le cancer le plus fréquent de la femme. Plusieurs types de cancer du sein ont été mis en évidence. Les carcinomes infiltrants triple négatif (TNBC) sont l'un de ces types. Les TNBC sont parmi les plus agressifs cancers du sein et sont associés à un mauvais pronostique. Il n'y a pas encore de traitement dédié pour ces cancers. Cette thèse avait pour but d'identifier des gènes et des voies de signalisation dérégulés dans les cancers de types TNBC en s'appuyant sur les profiles transcriptomiques et génomiques de tumeurs TNBC bien caractérisées, obtenues par la technique des biopuces. Mon travail comporte deux volets. D'abord, j'ai développé des méthodes pour l'analyse des données génomiques. J'ai proposé une méthode (ITALICS) pour la normalisation des données Affymetrix SNP 100K et 500K. J'ai travaillé sur la segmentation des profils génomiques. J'ai développé de nouveaux outils statistiques pour étudier la stabilité de la segmentation et j'ai obtenu des formules exactes pour des critères de sélection de modèle. Enfin, j'ai propose un algorithme de programmation dynamique rapide qui retrouve la meilleure segmentation au sens de la norme euclidienne. Dans un second temps, j'ai analysé les données omiques du projet. J'ai conçu le plan d'expérience. J'ai analysé les données transcriptomiques avec des méthodes déjà disponibles. J'ai comparé les classifications transcriptomique et immunohistochimique des TNBC. L'analyse des données transcriptomiques m'a permis d'identifier des gènes et des voies de signalisation dérégulés dans les TNBC. Enfin, j'ai analysé les données génomiques avec les outils que j'ai développés.
463

Gauge fixed gluonic observables and neutral kaon mixing on the lattice

Hudspith, Renwick January 2013 (has links)
This thesis presents gauge fixed gluonic observable and neutral Kaon mixing matrix element measurements using nf=2+1 Domain Wall Fermion (DWF) configurations. These were generated with the Iwasaki gauge action by the RBC and UKQCD collaborations. Results from the first measurement of the QCD strong coupling with these ensembles using the triple gluon vertex are shown. We find that while a very accurate measurement of the coupling is possible using this technique, the systematic error from the perturbative matching at current lattice scales is large. We also discuss the utilisation of this method as a probe for possible Technicolor theories. The calculation of the QCD strong coupling constant from the triple gluon vertex required an implementation of a fast code to fix lattice gauge configurations. I provide details on my implementation of a parallel and optimised Fourier-accelerated algorithm for both Landau and Coulomb gauge fixing. I include the first calculation of the highly accurate W0-scale using these ensembles, allowing for percent-level scale setting. I show results from a wide variety of smearing methods and present the first gluonic measurement of different smearing radii. This thesis also details the first nf=2+1 measurement of the BSM neutral Kaon mixing renormalised matrix elements from lattice simulations with almost exact chiral symmetry in the valence sector and the sea.
464

Validation of Spaceborne and Modelled Surface Soil Moisture Products with Cosmic-Ray Neutron Probes

Montzka, Carsten, Bogena, Heye, Zreda, Marek, Monerris, Alessandra, Morrison, Ross, Muddu, Sekhar, Vereecken, Harry 25 January 2017 (has links)
]The scale difference between point in situ soil moisture measurements and low resolution satellite products limits the quality of any validation efforts in heterogeneous regions. Cosmic Ray Neutron Probes (CRNP) could be an option to fill the scale gap between both systems, as they provide area-average soil moisture within a 150-250 m radius footprint. In this study, we evaluate differences and similarities between CRNP observations, and surface soil moisture products from the Advanced Microwave Scanning Radiometer 2 (AMSR2), the METOP-A/B Advanced Scatterometer (ASCAT), the Soil Moisture Active and Passive (SMAP), the Soil Moisture and Ocean Salinity (SMOS), as well as simulations from the Global Land Data Assimilation System Version 2 (GLDAS2). Six CRNPs located on five continents have been selected as test sites: the Rur catchment in Germany, the COSMOS sites in Arizona and California (USA), and Kenya, one CosmOz site in New SouthWales (Australia), and a site in Karnataka (India). Standard validation scores as well as the Triple Collocation (TC) method identified SMAP to provide a high accuracy soil moisture product with low noise or uncertainties as compared to CRNPs. The potential of CRNPs for satellite soil moisture validation has been proven; however, biomass correction methods should be implemented to improve its application in regions with large vegetation dynamics.
465

Modélisation globale de l'alimentation d'une emprise lubrifiée par émulsion : simulation numérique directe et analyse physique des phénomènes

Guillaument, Romain 07 December 2010 (has links)
L'objet de cette thèse est de modéliser et simuler des écoulements diphasique/triphasique à phase non miscibles. L'impact de plusieurs gouttes d' émulsion (eau/huile) sur une plaque mouillante l'huile est simulée. Ainsi, une méthode pour lisser l'interface (SVOF), afin d'obtenir une courbure précise, basée sur une méthode eulérienne de type "Volume Of Fluid" (VOF) spécifique au caractère multiphasique de l' écoulement est développée. Un modèle de ligne triple et un modèle de mouillabilité sont développés pour calculer les forces capillaires. Ces modèles et ces méthodes sont validées partir de données expérimentales puis utilisées pour simuler le Plate-Outet les écoulements macroscopiques au voisinage du cylindre de laminage / The scope of this dissertation is to model and simulate non-miscible multiphase °ows. Theimpact of several emulsion droplet on the wetting steel strip is simulated. So, the method ofsmooth VOF based on Eulerian "Volume Of Fluid" approach which is particulary adapted tointerfacial °ows is developed. The new method SVOF allows to calculate the curvature with abetter precison than other method. A wettability model and a triple line model are developedto calculate the capillary forces. This models and this methods validated on the experimentaldata and used to simulate the Plate-Out and the macroscopic °ows in neighbourhood of coldrolling system.
466

Targeting EGFR signalling pathway in triple negative breast cancer

Albukhari, Ashwag January 2014 (has links)
Epidermal growth factor receptor (EGFR) is frequently overexpressed in the majority of triple negative breast cancer patients (TNBC). However, the molecular determinants behind their limited response to EGFR-targeted therapies are poorly understood. Here, both the acute and chronic responses of TNBC to the EGFR-targeted therapy, cetuximab (CTX), have been investigated. The expression of EGFR has been analyzed in a cohort of 2000 breast cancer tumours from the public dataset as well as in a panel of breast cancer cell lines. Furthermore, the response of TNBC cell lines to CTX has been investigated using conventional biochemical methods. Finally, a comprehensive transcriptomic profiling of an acquired CTX-resistant TNBC model by RNA sequencing has been performed to understand the molecular determinants of acquired CTX resistance. The results confirmed that EGFR is highly expressed in TNBC in comparison to non-TNBC breast cancer tumours and cell lines, which was associated with adverse clinical outcomes. Targeting EGFR in TNBC cell lines using CTX failed to completely inhibit the EGFR signalling pathway and was associated with an increase in ADAMs-mediated release of endogenous EGFR ligands, EGF and TGFα. Inhibition of ADAMs (ADAM10 and ADAM17) significantly enhanced the anti tumour efficacy of CTX both in vitro and in vivo. Furthermore, transcriptomic profiling of the acquired CTX-resistant TNBC cell line (MDA-MB-468CR) revealed an activation of several key oncogenic pathways and genes, including the TGFβ/BMP pathway. Blocking BMP receptors (BMPRs) restored the sensitivity of resistant cells to CTX treatment. Collectively, current findings offer alternative strategies that could enhance the CTX response in TNBC. We further reported that simultaneous targeting of both EGFR and BMPR pathways could overcome CTX resistance, which might have important implications for the treatment of TNBC.
467

Fluctuations, Phase Separation and Wetting Films near Liquid-Gas Critical Point

Oprisan, Ana 22 May 2006 (has links)
Gravity on Earth limits the study of the properties of pure fluids near critical point because they become stratified under their own weight. Near the critical point, all thermodynamic properties either diverge or converge and the heating and cooling cause instabilities of the convective flow as a consequence of the expansibility divergence. In order to study boiling, fluctuation and phase separation processes near the critical point of pure fluids without the influence of the Earth's gravity, a number of experiments were performed in the weightlessness of Mir space station. The experimental setup called ALICE II instrument was designed to suppress sedimentation and buoyancy-driven flow. Another set of experiments were carried out on Earth using a carefully density matched system of deuterated methanolcycloxexane to observe critical fluctuations directly. The set of experiments performed on board of Mir space station studied boiling and wetting film dynamics during evaporation near the critical point of two pure fluids (sulfur hexafluoride and carbon dioxide) using a defocused grid method. The specially designed cell containing the pure fluid was heated and, as a result, a low contrast line appeared on the wetting film that corresponded to a sharp change in the thickness of the film. A large mechanical response was observed in response to the cell heating and we present quantitative results about the receding contact lines. It is found that the vapor recoil force is responsible for the receding contact line. Local density fluctuations were observed by illuminating a cylindrical cell filled with the pure fluid near its liquid- gas critical point and recorded using a microscope and a video recorder. Microscopic fluctuations were analyzed both in sulfur hexafluoride and in a binary mixture of methanol cyclohexane. Using image processing techniques, we were able to estimate the properties of the fluid from the recorded images showing fluctuations of the transmitted and scattered light. We found that the histogram of an image can be fitted to a Gaussian relationship and by determining its width we were able to estimate the position of the critical point. The characteristic length of the fluctuations corresponding to the maximum of the radial average of the power spectrum was also estimated. The power law growth for the early stage of the phase separation was determined for two different temperature quenches in pure fluid and these results are in agreement with other experimental results and computational simulations.
468

Detecção e correção de perdas de ciclos para dados GPS de tripla frequência /

Mendonça, Caio Henrique Chrisóstomo January 2019 (has links)
Orientador: Daniele Barroca Marra Alves / Resumo: A observável fase da onda portadora é utilizada quando se deseja obter alta acurácia no posicionamento por sistemas globais de navegação por satélite. Mas, esta observável pode sofrer perdas de ciclos durante o rastreamento do sinal. Uma perda de ciclo é uma descontinuidade de um número inteiro de ciclos na fase da onda portadora, causada por uma perda temporária de rastreamento do sinal pelo receptor. Assim, as perdas de ciclos devem ser detectadas e corrigidas para que se obtenha posicionamento acurado. Diversos métodos foram desenvolvidos com esse objetivo. Algo que também vem sendo amplamente estudado é a detecção das perdas de ciclos nos novos sinais GPS. O advento da terceira frequência disponibilizada a partir da modernização do GPS também deve ser explorado. Na presente pesquisa buscou-se estudar os diferentes métodos de detecção e correção de perdas de ciclos e implementar o mais adequado para o posicionamento de alta acurácia no Brasil. Foram selecionadas duas metodologias para fim de detecção e correção, sendo a primeira baseada no método das triplas diferenças (TD) clássico e a segunda baseada no método de sequência de combinações lineares. Além disso, foi proposta uma terceira metodologia para melhoria do método das TD. Foram realizados dois experimentos, sendo o primeiro realizado com dados simulados e o segundo com dados reais em período de alta atividade ionosférica, e para ambos os casos foram considerados dois cenários: linha de base curta e linha de base lo... (Resumo completo, clicar acesso eletrônico abaixo) / Abstract: Carrier phase observable are used in high accuracy positioning by global navigation satellite systems. However, the carrier phase measurement may suffer cycle slips during signal tracking. A cycle slip is a discontinuity of an integer number of cycles in the phase observable, caused by a temporary loss of lock in the receiver carrier tracking loop. Thus, cycle slips must be detected and corrected in order to obtain accurate positioning. Several methods were developed for this purpose. Something that has also been studied is the detection of cycle slip in the new GPS signals. The advent of the third frequency available from the GPS modernization. Should be explored in the context of cycle slip detection and correction. In the present research the different cycle slip detection and correction methods were studied and t the most suitable for the high accuracy positioning in Brazil was implemented. Two methodologies were selected for the purpose of this research, the first one based on the classical triple difference (TD) method and the second based on the linear combination sequence method. In addition, a third methodology was proposed to improve the TD method. Two experiments were performed, the first one being carried out with simulated data and the second with real data in the period of high ionospheric activity, and for both cases two scenarios were considered: short baseline and long baseline. For simulated short baseline data, the classical TD method, the proposed TD metho... (Complete abstract click electronic access below) / Mestre
469

Neural Substrates Correlated with Magnitude Processing in Children and Adults : An fMRI study examining the Triple Code Model of numerical cognition

Riddervold Sandberg, Eva January 2019 (has links)
The Triple Code Model (TCM) of numerical cognition has become one of the most predominantly theories for how humans perceive, manipulate, and communicate numerical information. It builds on the notion that there exist three functionally distinct but neurologically connected codes that handle manipulations of different numerical input (non-symbolic magnitudes, symbolic representations, and verbal number words). In this study, we add a developmental perspective by collecting child data and comparing it to existing adult data. The main question is whether or not children elicit the same neural correlates as adults while performing three different number comparison tasks in line with TCM. Neuroimaging data using fMRI were collected for a total of 20 participants (ten children and ten adults). The results suggest that children rely on more right-lateralized regions and that a developmental shift towards the left hemisphere and associated language areas occur during acquisition of mathematical proficiency. / <p>VG</p>
470

Epistasia e interação epistasia por locais para a produção de grãos em soja / Epistasis and epistasis by location interaction for grain yield in soybean

Acevedo Barona, Marco Antonio 10 December 2007 (has links)
Nos programas de melhoramentos de soja as progênies endogâmicas são frequentemente avaliadas como possíveis cultivares. O estudo da estrutura da variação genética entre progênies de diferentes gerações de autofecundação depende da ação dos locos envolvidos e da variação do caráter sob estudo. Em soja o caráter produção de grãos (PG) é considerado o de maior importância econômica e destaca-se por apresentar herança quantitativa e ser altamente influenciada pelo ambiente. As estratégias de seleção utilizadas para o desenvolvimento de cultivares em soja poderiam ser otimizadas através do estudo da importância relativa dos componentes de variância, particularmente a proporção de variação devida à interação não alélica (epistasia). Com o objetivo de estudar a variação epistática e sua interação com ambientes (locais) para a produção de grãos em soja utilizou-se o delineamento "Triple Test Cross Modificado" (TTC) de JINKS, PERKINS e BREESE (1969). Uma amostra de 32 linhagens (Pi) derivadas de um cruzamento biparental foi cruzada com duas linhagens divergentes (L1 e L2) contrastantes para PG, derivadas da mesma população (testadores). Os experimentos de avaliação foram conduzidos no ano agrícola de 2006/2007 em dois locais (Piraciacaba e Anhembi) em delineamentos em látice triplo 10 x 10. Os tratamentos correspondiam aos 32 cruzamentos Pi x L1, 32 cruzamentos Pi x L2, 34 linhas puras (32 Pi + 2 testadores) e duas testemunhas comerciais. De acordo com a metodologia utilizada foram estudados os contrastes ( i 2i 1i P L L - + ) para avaliar a ocorrência de epistasia. Os resultados das análises individuais mostraram que a epistasia afetou a expressão da produção de grãos em ambos os locais. A análise conjunta permitiu detectar significância para locais, epistasia e interação epistasia por locais, indicando que a produção de grãos em soja é afetada pela interação não alélica (epistasia) e que esta não é consistente entre locais. O estudo do contraste ( i 2i 1i P L L - + ) das médias individuais nas análises por local e na análise conjunta indicou haver contribuição diferencial dos genótipos para a epistasia. Os resultados gerais indicam que a epistasia pode ser um componente importante para a expressão da produção de grãos de soja e, consequentemente, esta deveria ser incluída nos modelos para a decomposição dos componentes da variância genética. / In soybean breeding programs the selfing progenies are generally evaluated as possible cultivars. The study of the structure of the genetic variation among progenies in different generations of selfing depends upon the action of the loci involved and the variability of the trait under study. In soybeans, grain yield is the most important trait and it is characterized by a quantitative inheritance and highly influenced by the environment. The selection strategies used for the development of soybean cultivars could be optimized through the study of the relative importance of the variance components, in particular the proportion of the non-allelic interaction component (epistasis). In order to study the epistatic variation and its interaction with locations for grain yield in soybeans the "Modified Triple Test Cross" (TTC) method (JINKS, PERKINS e BREESE, 1969) was used. A sample of 32 inbred lines (Pi) derived from a single cross were crossed with two divergent inbred lines (L1 e L2) of the same population (testers). The experiments were carried out in the 2006/2007 growing season in two locations (Piracicaba and Anhembi) in a 10x10 triple lattice design. Entries consisted of the 32 Pi x L1 crosses, 32 Pi x L2 crosses, 34 lines (Pi + 2 testers) and 2 commercial checks. Following the methodology, the contrasts ( i 2i 1i P L L - + ) were studied in order to evaluate the occurrence of epistasis. General results showed that epistasis affected grain yield in soybeans in both locations. Significance for locations, epistasis and epistais by locations interactions were also detected in the joint analysis of variance, indicating that grain yield in soybeans is affected by the non-allelic interaction (epistasis) and that the epistasis is not consistent in different locations. A study of the contrast ( i 2i 1i P L L - + ) of individual means for each location and in the joint analyses indicated the occurrence of differential contribution of the genotypes for the epistasis. General results had demonstrated that epistasis could be an important component for the expression of grain yield in soybeans and consequently it should be included in the model for the partition of the genetic components of variance.

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