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1
Gavenčiak, Michal. "Výzkum nových parametrů online písma u dětí s grafomotorickými obtížemi." Master's thesis, Vysoké učení technické v Brně. Fakulta elektrotechniky a komunikačních technologií, 2021. http://www.nusl.cz/ntk/nusl-442574.
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In the Czech Republic, there is currently no objective method to diagnose graphomotor difficulties in children. Ongoing research uses modern digitizers to capture the hand-writing process and quantify its parameters. The first goal of this thesis is to develop software tools to faciliate work with the collected data, such as database validation and writing exercise rating, done by specialists. Another goal of this thesis is to design new on-line handwriting parameters which are then to be analysed on a cohort of school children from 2nd to 4th class of primary school (n=239). The implementation of two desktop programs on the .NET platform is described, among three new quantifying parameters based on the principles of isochrony, two-dimensional cross-correlation, and geometrical centroid. All three parameters show significant correlation (r = [0,2; 0,3])with the HPSQ-C rating in 2nd- and 4th-graders and correlation (𝜌= [0,2; 0,5]) with specialist’s subjective scores in all children from the cohort. The analysis suggests children with graphomotor difficulties struggle with regulating handwriting speed and working memory.
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Tachon, Thibaut. "Génération automatique de code parallèle isochrone." Thesis, Orléans, 2019. http://www.theses.fr/2019ORLE3098.
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Depuis la stagnation de la fréquence d’horloge des processeurs, l’accroissement de la puissance de calcul a dépendu entièrement de l’accroissement du nombre d’unités de calcul. Plus que la difficulté algorithmique impliquée par l’écriture de tout programme séquentiel, la programmation parallèle demande au programmeur de gérer de nombreuses unités de calcul, incluant leurs tâches et leurs interactions. Pour alléger le fardeau du programmeur, cette thèse propose deux approches différentes de génération automatique de code parallèle. Le modèle parallèle isochrone BSP possède des propriétés intéressantes telles que son modèle de coût qui en font la cible de notre génération de code parallèle. Les automates et expressions régulières sont souvent choisis pour modéliser les calculs séquentiels et leurs parallélisation devrait, à long terme, aboutir à de solides fondations pour la génération de code parallèle. Pour notre approche principale, nous développons la théorie des automates BSP avec leur génération et détermination. Cette théorie est utilisée dans une nouvelle méthode pour la recherche de motif à l’aide d’expressions régulières. Notre autre approche propose un langage spécifique au domaine des réseaux de neurones où la composition fonctionnelle d’un petit nombre de primitives facilite le développement, la maintenance et la définition formelle du langage par rapport aux approches existantesSince we are in an era of processor clock stagnation, computing power growth has been relying on parallel computing. More than the algorithmic difficulty involved in any program writing, parallel computing additionally requires the programmer to manage numerous processing units including their tasks and interactions. In order to alleviate the parallel programmer’s burden, this thesis proposes two different approaches for automatic parallel code generation. The bulk-synchronous parallel (BSP) model provides good properties such as its cost model and is therefore chosen as the target of our parallel code generation.Automata and regular expressions are often chosen to model sequential computation and their parallelization will lead to a strong foundation for general parallel code generation. For our main approach, we develop the theory of BSP automata with their generation and determinization. This theory is used in a novel method for parallel regular expression matching.As another approach, we propose a domain specific language for programming neural nets where the functional composition of only a few primitives eases development, maintenance and formal definition of the language compared to existing approaches
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Gubler, Lukas. "Isochrone Flugzeit-Massenspektrometer für den Einsatz im Weltraum /." [S.l.] : [s.n.], 1994. http://www.ub.unibe.ch/content/bibliotheken_sammlungen/sondersammlungen/dissen_bestellformular/index_ger.html.
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Guzman, Borrero Jose E. "Isochronal: A Suite for Jazz Orchestra." OpenSIUC, 2016. https://opensiuc.lib.siu.edu/theses/1908.
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AN ABSTRACT OF THE THESIS OF José E. Guzmán Borrero, for the Master of Music degree in Music Theory and Composition, presented on April 8, 2016, at Southern Illinois University Carbondale. TITLE: ISOCHRONAL: A SUITE FOR JAZZ ORCHESTRA MAJOR PROFESSOR: Dr. Christopher Walczak The suite is a three movement composition for jazz orchestra in which I integrate contemporary compositional methods with the harmonic idioms of the jazz genre. The first movement, “Flight,” takes a minimalist (ca. 1970-1990) approach through the beginning of the piece, then incorporates a development section reminiscent of music from the Classical period with the use of two and three voice counterpoint. Followed by a traditional jazz solo section. The second movement, “'Round Ten” is a ballad featuring the post-tonal compositional method of dodecaphony (ca. 1925-1950) in tandem with melodic and harmonic jazz expressions reminiscent of Thelonious Monk. My compositional use of tone rows is similar to the methods of Benjamin Britten and Alban Berg, who used the row as a compositional guideline or tool. This is unlike the initial use of the row by its founder, Arnold Schoenberg, which restricted the composer by the necessity of using all twelve pitches (with no emphasis on a tonal center) and using it in a predetermined order. The ballad section of the second movement is similar to Thelonious Monk's music in its use of non-harmonic tones and sharp dissonances mixed with a repetitive melodic contour. The third and final movement, “Lights Out!” is an up-tempo piece that uses the dense harmonies reminiscent of Don Menza and Thad Jones’ arrangements. The harmonic structure of the piece is from the modal jazz period of the 1960s in which composers pushed the boundaries of the typical 32-bar song format. The melodic material in this movement includes material from the two previous movements.
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SCHUMAN, BERTRAND. "Sur le probleme du centre isochrone des systemes hamiltoniens polynomiaux." Paris 6, 1998. http://www.theses.fr/1998PA066617.
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On presente une approche du probleme du centre qui utilise la theorie des formes normales de germes de champs de vecteurs polynomiaux a l'origine dans r 2 n. Un de nos points de vue est l'effectivite, au sens ou on utilise le calcul formel pour obtenir et calculer les coefficients de la forme normale de birkhoff. On calcule explicitement les premiers coefficients de la forme normale d'un champ de vecteurs hamiltonien polynomial homogene, et un debut d'etude des champs hamiltoniens non homogenes est entreprise, au sens ou, la aussi, on calcule completement les premiers coefficients des formes normales mises en jeu. Notre travail permet d'attacher des invariants algebriques aux champs de vecteurs, et donc d'ebaucher une classification de ces champs. De plus, les equations algebriques provenant des ces invariants completement explicites dans certains cas, en particulier pour le cas hamiltonien, permettent de generer des conditions pour la linearisation des champs polynomiaux au voisinage de l'origine, qui est un point critique de type elliptique. Le probleme de la linearisation, ou encore du probleme du centre, est ainsi aborde par le biais des varietes algebriques definies par les equations associees aux champs de vecteurs etudies.
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Krüger, Frank, Matthias Ohrnberger, and Dirk Rößler. "Rupture imaging of large earthquakes with a poststack isochrone migration method." Universität Potsdam, 2008. http://opus.kobv.de/ubp/volltexte/2008/1839/.
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Rapid and robust characterization of large earthquakes in terms of their spatial extent and temporal duration is of high importance for disaster mitigation and early warning applications. Backtracking of seismic P-waves was successfully used by several authors to image the rupture process of the great Sumatra earthquake (26.12.2004) using short period and broadband arrays. We follow here an approach of Walker et al. to backtrack and stack broadband waveforms from global network stations using traveltimes for a global Earth model to obtain the overall spatio-temporal development of the energy radiation of large earthquakes in a quick and robust way. We present results for selected events with well studied source processes (Kokoxili 14.11.2001, Tokachi-Oki 25.09.2003, Nias 28.03.2005). Further, we apply the technique in a semi-real time fashion to broadband data of earthquakes with a broadband magnitude >= 7 (roughly corresponding to Mw 6.5). Processing is based on first automatic detection messages from the GEOFON extended virtual network (GEVN).
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Ozgit, Cagla. "Isochronal Hydrogenation Of Textured Magnesium/palladium Thin Films." Master's thesis, METU, 2009. http://etd.lib.metu.edu.tr/upload/12610385/index.pdf.
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Pure and palladium‐
covered 350 nm thick magnesium thin films were deposited on glass substrates via thermal evaporation. In the as&
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deposited state, films were highly textured with Mg (001) parallel to the substrate. Hydrogen loading experiments were carried out in two different conditions
namely isothermal and isochronal. Hydrogenation behaviors of the thin films were followed by twopoint probe electrical resistance and optical transmittance measurements, as well as x&
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ray diffraction studies. Isothermal hydrogenation experiments conducted on Pd&
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covered Mg thin films have revealed that these films can absorb hydrogen at temperatures starting from 333 K, producing MgH2 with a random texture. When the films were heated slowly starting from the room temperature, on the other hand, hydrogenation gives rise to a textured MgH2, where (110) parallel to the substrate with a minor (101) component. Formation of the textured hydride in isochronal loading was discussed within the context of lattice mismatch in Mg to MgH2 transformation. It was further shown that formation of such a textured hydride in Mg thin films minimizes in&
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plane lattice distortion.
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Clark, Peter Alan. "Isochron methods for luminescence dating in archaeology." Thesis, University of Glasgow, 1994. http://theses.gla.ac.uk/7225/.
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This work aims to contribute to the solution of a problem relevant to archaeology and microdosimetry, namely the TL dating of destratified archaeological ceramics. It is apparent that museums hold a large body of archaeological material excavated from important sites during the early part of this century. Absolute dating of this corpus of material would be extremely valuable to archaeology in allowing historic hypotheses to be tested. The background to this problem has been presented within the context of the historical development of thermoluminescence dating and of dosimetry concepts. A critical review of previously proposed strategies for dating material from unknown gamma contexts is presented, and then a general model using an isochron approach is introduced. The isochron model is then developed explicitly and theoretical simulation is used to explore different microdosimetric systems. Two main isochron solutions have been identified, the grain size (or alpha-beta attenuation) and alpha efficiency isochrons. An experimental approach was designed, to evaluate the validity of the grain size isochron predictions, using model matrices. Isochron behaviour was clearly observed in both cases. The first system, based on microcline feldspar grains in a high dose rate matrix, produced an age estimate consistent with the known age. The second experiment, using fluorite grains in a lower dose rate matrix, produced a highly coherent data set. However, the age estimate obtained was greater than the expected value by a factor of approximately 3. The possible reasons for this are discussed in detail. A brief experiment carried out subsequently on duplicate portion of this matrix gave results that are consistent with predicted values. Thus, it would appear that the original experimental design and method were valid and that the isochron approach does indeed deserve further investigation.
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Ahlvind, Julia. "Isochrone and chemical ages of stars in the old open cluster M67." Thesis, Uppsala universitet, Observationell astrofysik, 2021. http://urn.kb.se/resolve?urn=urn:nbn:se:uu:diva-434634.
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The open cluster Messier 67 is known to have chemical composition, metallicity and age (~ 4 Gyr) close to the Sun. Therefore, it is advantageous for stellar physical studies and of stellar evolution, in particular for solar like stars within the cluster. This work considers three such stars, the formerly studied solar twin M67-1194 and two more recently suggested solar twins M67-1787 & 2018. Most solar twins show a ratio of volatile to refractory elements that systematically depart from the Sun’s. Our targets do not follow this trend as closely. Their composition is closer to the Sun and they are, therefore, exquisite targets for studies of stellar evolution within the cluster. However, their solar likeness also provides studies regarding the origin and evolution of the Solar system. The stellar ages of the solar twins are established through a chemical clock [Y/Mg] and via stellar isochrones from BaSTI. The latter age assessment of the solar twins is supplemented with the analysis of two subgiant stars M67-1442 & 1844. We approach the isochrone-based method using spectroscopically, astrometrically and photometrically derived parameters. The different ages of the stars and methods thus estimate the age of the cluster itself. The chemical ages of the stars suggest a cluster age of 4.56 ±0.44 Gyr and the isochrone-based estimates suggests a cluster age within the range 3.30-5.51 Gyr. Our results thus affirm and imply a near solar age of the cluster.
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Grzybowski, José Mario Vicensi. "Isochronal synchronization of delay-coupled chaotic systems and networks." Instituto Tecnológico de Aeronáutica, 2012. http://www.bd.bibl.ita.br/tde_busca/arquivo.php?codArquivo=2043.
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A sincronização estável de redes tem papel central em diversos fenômenos de interesse científico, e.g., arritmias cardíacas, crises epiléticas e o desempenho de atos cognitivos no cérebro. Assim, a estabilidade da sincronização e as condições que levam às fronteiras de instabilidade são tópicos de interesse científico considerável. Entretanto, no que diz respeito à sincronização isócrona (com atraso zero), a literatura está desprovida de ferramentas gerais e analíticas para estudar e determinar a estabilidade da sincronização. Enfoques existentes não fornecem metodologias gerais e, além disso, fazem uso de hipóteses improváveis do ponto de vista prático. Considerando o teorema de Lyapunov-Krasovskii, o problema da estabilidade da sincronização isócrona é formulado e resolvido de forma a propor alternativas para eliminar essas hipóteses restritivas. A solução consiste em expressões analíticas que revelam a dependência da estabilidade da sincronização em relação aos parâmetros da rede. Como resultado, um conjunto de ferramentas é introduzido para explorar a estabilidade da sincronização isócrona em redes complexas de osciladores caóticos com atraso de acoplamento. Para avaliar o conservadorismo dos resultados e para aumentar o escopo dos resultados, simulações numéricas são realizadas e avaliadas. Finalmente, é apresentada a aplicação da sincronização isócrona em comunicação baseada em caos e TDMA, que emprega a sincronização para estabelecer comunicação coordenada entre os nós de redes de osciladores.
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Spowage, Andrew Christopher. "Understanding the fundamental ageing behaviour of Al-Li-Cu-Mg alloys." Thesis, University of Nottingham, 1999. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.311912.
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An, Deokkeun. "Improving the Local Distance Scale from Empirically Calibrated Stellar Isochrones." The Ohio State University, 2008. http://rave.ohiolink.edu/etdc/view?acc_num=osu1218593380.
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Zhao, Hui, and 趙暉. "Studies of isochron luminescence dating with sand-sized grains." Thesis, The University of Hong Kong (Pokfulam, Hong Kong), 2002. http://hub.hku.hk/bib/B42577329.
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Zhao, Hui. "Studies of isochron luminescence dating with sand-sized grains." Click to view the E-thesis via HKUTO, 2002. http://sunzi.lib.hku.hk/hkuto/record/B42577329.
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Jones, Jeffrey A. "Simulating an isochronal scheduled inspection system for the P-3 Orion." Thesis, Monterey, Calif. : Springfield, Va. : Naval Postgraduate School ; Available from National Technical Information Service, 1998. http://handle.dtic.mil/100.2/ADA356616.
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Thesis (M.S. in Operations Research) Naval Postgraduate School, September 1998."September 1998." Thesis advisor(s): George W. Conner. Includes bibliographical references (p. 55-56). Also available online.
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Schatz, G. [Verfasser]. "Ein Verfahren zur Aenderung des Feldanstieges in isochronen Ringzyklotrons / G. Schatz." Karlsruhe : KIT-Bibliothek, 2009. http://d-nb.info/118690562X/34.
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Caulfield, Anne Jeanette. "In search of isochrony : compensating for durational warping in speech production." Thesis, University of British Columbia, 1985. http://hdl.handle.net/2429/24587.
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The rhythmic organization of speech into regular intervals (i.e. isochrony), is a strong perceptual phenomenon. However, Investigators have been unable to demonstrate the existence of isochrony in production data. It is hypothesized in this study that the intended rhythm of a speaker is in fact isochronous, but that this is obscured by several distorting influences which introduce durational irregularity at the syllable level, e.g. intrinsic duration, stress, position of the syllable in a phrase and number of syllables in a phrase. It is proposed that removing the predictable durational irregularities will yield a more regular signal, reflecting the (hypothesized) Intended Isochronous rhythm of the speaker. The latter two sources of distortion introduce progressive durational irregularity or "warping" which can be readily incorporated into an automated "dewarplng" procedure. A computer program was devised to compensate, at the syllable level for these two sources of distortion. The former two sources are not amenable to such an automated procedure, and were therefore not included. The "dewarping" program was run on the speech amplitude envelopes of two speakers, one French and one English.
The results indicate that, for the French speaker, dewarping does remove some of the durational Irregularity, yielding a more regular amplitude envelope. For the English speaker, no such Improvement in regularity is obtained. This indicates that the dewarping used, which presumes the syllable as "unit" of dewarping, is appropriate for syllable-timed languages such as French, but inappropriate for stress-timed languages such as English. It therefore provides some support for isochrony in French at the syllable level. Finally, the results also give support to the hypothesis that the degree of warping perceived as regular in speech perception studies corresponds to the degree of dewarping which, conversely, yields the most regular speech amplitude envelope; however, further experimentation is necessary to determine the optimum values of the parameters of the dewarping function.Medicine, Faculty of
Audiology and Speech Sciences, School of
Graduate
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Blanco, Miguel Alfonso. "Modèle d'isochrones automatisé du mouvement potentiel des personnes portées disparues." Mémoire, Université de Sherbrooke, 2016. http://hdl.handle.net/11143/8362.
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Résumé : Au Canada, annuellement il y a près de 10 000 personnes disparues. Pour les retrouver chaque fois une alerte est donnée. La police et les groupes de recherche terrestre spécialisés travaillent pour la retrouver, mais, par où commencer? Dans quelles directions orienter les recherches? Combien du temps pour balayer les différents secteurs? C’est souvent une question d’heures ou même des minutes pour la retrouver vivante.
La théorie de recherche a trois concepts essentiels; la probabilité d’aire, la probabilité de détection et la probabilité de succès. Notre travail a cherché à préciser la probabilité d’aire.
L’objectif de ce travail de recherche a consisté à développer un algorithme pour élaborer des cartes d’isochrones automatiques de la vitesse de marche probable des disparus. Il tient compte des restrictions dues aux variables environnementales (relief, occupation du sol, météorologie) et anthropiques (âge, sexe, taille, poids et activité physique).
Le travail est développé au tour d’un système d’information géographique. Sur ceci nous distinguons deux groupes des données. Le premier correspond aux données attributaires que servent à générer la zone tampon et les facteurs de vitesse de l’individu. Ces données sont attachées à la couche du point initial. Dans le deuxième groupe, nous trouvons les données à référence spatiale intérieures à la zone tampon. Les facteurs de vitesse de l’individu et la carte de pentes génèrent la carte de vitesses par superficie. Les données de couverture de sol, quant à elles, produisent la carte de coût de traversée de la superficie. Finalement, la multiplication des deux dernières cartes produit la carte de coût de voyage, laquelle est le résultat essentiel pour concevoir la carte des courbes isochrones.
Un algorithme a été construit et développé en langage de programmation Python. Il a été exécuté avec des données saisies dans l’environnement d’ArcGis 10.2.
Nous avons observé une tendance des disparus à rester dans un rayon d’une heure de marche à partir du point initial (Pl). De plus, des variables comme les routes, sentiers et lignes de transport d’énergie influencent la marche. Finalement nous avons trouvé que l’outil aide au confinement de la probabilité d’aire.
L’outil se démarque par sa simplicité d’usage. À l’intégration des facteurs de marche qui sont reliés à l’individu. Ainsi qu’à l’inclusion des facteurs météorologiques. Il peut s’exécuter partout au Canada.Abstract : In Canada, annually there are about 10 000 missing persons. To find them whenever a warning is given. Police and specialized ground search groups work to find her, but where to start? In what directions guide research? How much time to scan the different sectors? It is often a matter of hours or even minutes to find her alive. The search theory has three basic concepts; the probability of area, the probability of detection and probability of success. Our work has sought to precise the probability of area in land search. The aim of this research was to develop an algorithm to make automatic isochrone maps that show the probability walking time of the missing person. It takes account of restrictions due to environmental variables (topography, land use, meteorology) and anthropogenic (age, sex, height, weight and physical activity). The work was developed around a geographic information system. On top of this, we distinguish two groups of data. The first is the attribute data that are used to generate the buffer zone and the individual speed factors. These data are attached to the initial planning point layer. In the second group, we find the internal spatial data in the buffer zone. The individual factors of speed and slope map produced the speed map. Ground cover data generated the cost map of crossing the area. Finally, the multiplication of the last two maps produced the travel cost map, which is the last step to design the isochrone map. An algorithm has been built and developed in the Python programming language. It was performed with the data entered into the ArcGIS 10.2 environment. We observed a trend of lost persons to stay around an hour's walk from the initial planning point (IPP). In addition, variables such as roads, paths and power transmission lines affect the walking speed. We found that the tool aid to precise the containment of probability of area. The tool is distinguished by its ease of use. With the integration of walking factors that are connected to the lost persons. We include meteorological factors. It can run across Canada.
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Cao, Alexander. "Dimension Reduction for Stochastic Oscillators: Investigating Competing Generalizations of Phase and Isochrons." Case Western Reserve University School of Graduate Studies / OhioLINK, 2017. http://rave.ohiolink.edu/etdc/view?acc_num=case1490811963129832.
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Rippon, Cyril. "Clio et l'extension de son domaine spectral : étude de l'adaptation du faisceau d'electrons dans l'onduleur." Paris 7, 2003. http://www.theses.fr/2003PA077105.
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Bell, Cameron Pearce MacDonald. "A critical assessment of ages derived using pre-main-sequence isochrones in colour-magnitude diagrams." Thesis, University of Exeter, 2012. http://hdl.handle.net/10036/4017.
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In this thesis a critical assessment of the ages derived using theoretical pre-main-sequence (pre-MS) stellar evolutionary models is presented by comparing the predictions to the low-mass pre-MS population of 14 young star-forming regions (SFRs) in colour-magnitude diagrams (CMDs). Deriving pre-MS ages requires precise distances and estimates of the reddening. Therefore, the main-sequence (MS) members of the SFRs have been used to derive a self-consistent set of statistically robust ages, distances and reddenings with associated uncertainties using a maximum-likelihood fitting statistic and MS evolutionary models. A photometric method (known as the Q-method) for de-reddening individual stars in regions where the extinction is spatially variable has been updated and is presented. The effects of both the model dependency and the SFR composition on these derived parameters are also discussed. The problem of calibrating photometric observations of red pre-MS stars is examined and it is shown that using observations of MS stars to transform the data into a standard photometric system can introduce significant errors in the position of the pre-MS locus in CMD space. Hence, it is crucial that precise photometric studies (especially of pre- MS objects) be carried out in the natural photometric system of the observations. This therefore requires a robust model of the system responses for the instrument used, and thus the calculated responses for the Wide-Field Camera on the Isaac Newton Telescope are presented. These system responses have been tested using standard star observations and have been shown to be a good representation of the photometric system. A benchmark test for the pre-MS evolutionary models is performed by comparing them to a set of well-calibrated CMDs of the Pleiades in the wavelength regime 0.4−2.5 μm. The masses predicted by these models are also tested against dynamical masses using a sample of MS binaries by calculating the system magnitude in a given photometric band- pass. This analysis shows that for Teff ≤ 4000 K the models systematically overestimate the flux by a factor of 2 at 0.5 μm, though this decreases with wavelength, becoming negligible at 2.2 μm. Thus before the pre-MS models are used to derive ages, a recalibration of the models is performed by incorporating an empirical colour-Teff relation and bolometric corrections based on the Ks-band luminosity of Pleiades members, with theoretical corrections for the dependence on the surface gravity (log g). The recalibrated pre-MS model isochrones are used to derive ages from the pre-MS populations of the SFRs. These ages are then compared with the MS derivations, thus providing a powerful diagnostic tool with which to discriminate between the different pre- MS age scales that arise from a much stronger model dependency in the pre-MS regime. The revised ages assigned to each of the 14 SFRs are up to a factor two older than previous derivations, a result with wide-ranging implications, including that circumstellar discs survive longer and that the average Class II lifetime is greater than currently believed.
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Quinsat, Michael. "Etude d'un auto-oscillateur non-isochrone : Application à la dynamique non-linéaire de l'aimantation induite par transfert de spin." Phd thesis, Université de Grenoble, 2012. http://tel.archives-ouvertes.fr/tel-00846484.
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Les oscillateurs à transfert de spin (STO) sont des oscillateurs Radiofréquence nanométriques dont la fréquence peut être variée d'un ordre de grandeur. Cette forte agilité en fréquence provient des propriétés non-linéaires de la dynamique de l'aimantation induite par le transfert de spin (STT) dans des multicouches magnétiques nano-structurées. Cette forte agilité en fréquence a le désavantage d'induire une forte sensibilité au bruit. La pureté spectrale des STO est alors bien en dessous des pré-requis pour les applications en télécommunications. Les principales propriétés de la dynamique de l'aimantation induite par le STT ont été décrites simplement à l'aide de la théorie non-linéaire des ondes de spin. Cependant des informations importantes sur le mode d'excitation sont enfouies dans des paramètres phénoménologiques tels que le couplage amplitude-phase NU et le taux de relaxation Gp. La détermination de ces paramètres avec précision est d'un intérêt primordial pour la description de la dynamique non-linéaire. Cette thèse décrit plusieurs méthodes expérimentales pour extraire ces paramètres. La première est la spectroscopie de bruit depuis le domaine temporel qui permet l'extraction des Densités Spectrales de Puissance du bruit d'amplitude et de phase. Leur analyse dans le cadre des modèles théoriques permet non seulement d'extraire directement les paramètres non-linaires mais également de quantifier le bruit de phase qui a un intérêt technologique. Ceci est démontré pour des dispositifs basés sur des jonctions tunnels magnétiques. La deuxième méthode est basée sur l'analyse des largeurs de raies des harmoniques du signal, où il est montré que du fait des propriétés non-isochrones des STO, la relation entre Dfn et Df1 est non triviale et permet l'extraction de NU et Gp. Nous utilisons alors toutes les informations obtenues sur le régime autonome de la dynamique des STO pour comprendre leur dynamique non-autonome qui sont des pré-requis à leurs utilisations dans des architectures RF complexes.
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Quinsat, Michaël. "Etude d'un auto-oscillateur non-isochrone : Application à la dynamique non-linéaire de l'aimantation induite par transfert de spin." Thesis, Grenoble, 2012. http://www.theses.fr/2012GRENY083/document.
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Les oscillateurs à transfert de spin (STO) sont des oscillateurs Radiofréquence nanométriques dont la fréquence peut être variée d'un ordre de grandeur. Cette forte agilité en fréquence provient des propriétés non-linéaires de la dynamique de l'aimantation induite par le transfert de spin (STT) dans des multicouches magnétiques nano-structurées. Cette forte agilité en fréquence a le désavantage d'induire une forte sensibilité au bruit. La pureté spectrale des STO est alors bien en dessous des pré-requis pour les applications en télécommunications. Les principales propriétés de la dynamique de l'aimantation induite par le STT ont été décrites simplement à l'aide de la théorie non-linéaire des ondes de spin. Cependant des informations importantes sur le mode d'excitation sont enfouies dans des paramètres phénoménologiques tels que le couplage amplitude-phase NU et le taux de relaxation Gp. La détermination de ces paramètres avec précision est d'un intérêt primordial pour la description de la dynamique non-linéaire. Cette thèse décrit plusieurs méthodes expérimentales pour extraire ces paramètres. La première est la spectroscopie de bruit depuis le domaine temporel qui permet l'extraction des Densités Spectrales de Puissance du bruit d'amplitude et de phase. Leur analyse dans le cadre des modèles théoriques permet non seulement d'extraire directement les paramètres non-linaires mais également de quantifier le bruit de phase qui a un intérêt technologique. Ceci est démontré pour des dispositifs basés sur des jonctions tunnels magnétiques. La deuxième méthode est basée sur l'analyse des largeurs de raies des harmoniques du signal, où il est montré que du fait des propriétés non-isochrones des STO, la relation entre Dfn et Df1 est non triviale et permet l'extraction de NU et Gp. Nous utilisons alors toutes les informations obtenues sur le régime autonome de la dynamique des STO pour comprendre leur dynamique non-autonome qui sont des pré-requis à leurs utilisations dans des architectures RF complexesSpin Torque Oscillators (STO) are nano-sized Radio-Frequency oscillators whose frequency agility can be tuned by an order of magnitude. This tuning originates from the non-linear properties of the underlying magnetization dynamics that is induced by spin transfer torque (STT) in multilayered magnetic nanostructures. Being highly tunable in frequency has the inconvenient of creating a very strong sensitivity to noise. As a result the spectral purity of STOs is far below the one required for applications for instance in telecommunications. The magnetization dynamics induced by STT has been described theoretically in the frame of nonlinear spin wave theory that makes the essential features of the underlying properties very transparent. However important information on the excitation mode are "buried" in phenomenological parameters such as NU the amplitude-phase coupling and Gp the amplitude relaxation rate. Determining these parameters with accuracy from experiments is thus an important issue. This thesis describes several experimental methods to extract these parameters. The first is time domain noise spectroscopy which permits to extract phase and amplitude noise Power Spectral Densities. Their analysis in the frame of theoretical models allows direct extraction of the nonlinear parameters, but also to quantify the technological relevant phase noise. This is demonstrated for magnetic tunnel junction devices. A second method is the analysis of higher harmonics linewidth, where it is shown that due to the non-isochronous property of STOs, the relationship between Dfn and Df1 is non-trivial and allows to extract NU and Gp. We then apply the information gathered on the autonomous dynamics of STOs to understand the non-autonomous dynamics of STOs that are a prerequisite for the use of STOs in complex RF architectures. It is shown experimentally how the nonlinear parameters influence this non-autonomous behaviour
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Boussaada, Islam. "Contribution à l'étude des solutions périodiques et des centres isochrones des systèmes d'équations différentielles ordinaires plans." Phd thesis, Université de Rouen, 2008. http://tel.archives-ouvertes.fr/tel-00348281.
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Le sujet global de cette thèse est l'étude des solutions périodiques des systèmes plans d'équations différentielles ordianaires. Elle est divisée en deux grandes parties.La première partie, (il s'agit d'un travail publié et écrit en collaboration avec R. Chouikha) est consacré à la recherche des solutions périodiques de « l'équation de Liénard généralisée ». On démontre un théorème qui asure dans certains cas l'existence de telles solutions.
La seconde partie est consacré à la recherche de centres isochrones de systèmes d'équations différentielles ordinaires polynomiaux plans. Grâce à l'usage de C-algorithme, on détermine huit nouveaux cas. On montre aussi l'efficacité de la méthode des formes normales dans de telles recherches, en examinant des systèmes d'ordre 2, 3, 4 et en retrouvant de manière uniforme plusieurs résultats déjà connus.
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TADESSE, Tarekegn, Kazuhiro SUZUKI, and Mitsuo HOSHINO. "Chemical Th-U-total Pb isochron age of zircon from the Mereb Granite in northern Ethiopia." Dept. of Earth and Planetary Sciences, Nagoya University, 1997. http://hdl.handle.net/2237/2833.
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Hug, Florian Verfasser], Norbert [Akademischer Betreuer] Pietralla, and Achim [Akademischer Betreuer] [Richter. "Erhöhung der Energieschärfe des Elektronenstrahls am S-DALINAC durch nicht-isochrones Rezirkulieren / Florian Hug. Betreuer: Norbert Pietralla ; Achim Richter." Darmstadt : Universitäts- und Landesbibliothek Darmstadt, 2013. http://d-nb.info/1106454812/34.
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Gonin, Marc. "Ein semiempirisches Modell des Ladungsaustausches von niederenergetischen Ionen beim Durchgang durch dünne Folien, zur Eichung von isochronen Flugzeit-Massenspektrometern /." [S.l : s.n.], 1995. http://www.ub.unibe.ch/content/bibliotheken_sammlungen/sondersammlungen/dissen_bestellformular/index_ger.html.
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Hug, Florian [Verfasser], Norbert Akademischer Betreuer] Pietralla, and Achim [Akademischer Betreuer] [Richter. "Erhöhung der Energieschärfe des Elektronenstrahls am S-DALINAC durch nicht-isochrones Rezirkulieren / Florian Hug. Betreuer: Norbert Pietralla ; Achim Richter." Darmstadt : Universitäts- und Landesbibliothek Darmstadt, 2013. http://d-nb.info/1106454812/34.
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Uwakweh, Oswald Nnanyere Chiedozie. "Distribution des interstitiels dans les alliages FE-C : cinétique isochrome au cours du vieillissement des martensites et transformation induite par chargement électrolytique d'hydrogène." Nancy 1, 1990. http://www.theses.fr/1990NAN10176.
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L'étude de la phase austénitique des alliages binaires FE-C par effet mossbauer à électrons de conversion (CEMS) révèle trois types d'environnement du fer qui mettent en évidence le caractère répulsif de l'intéraction entre atomes de carbone, et la mise en ordre de ce dernier dans la phase austénitique (FE#8C#1##X). Les spectres mossbauer des alliages FE-(1. 6 A 1. 9%) PD C de martensite brute de trempe montrent cinq types d'environnement du fer. Les mesures de cinétique par effet mossbauer et diffraction de rayons X sur des échantillons ayant subi des traitements isochrones nous permettent de déceler deux étapes au cours du vieillissement : une mise en amas des interstitiels (énergie d'activation de 752. 5 KJ/Mole), suivie d'une mise en ordre (énergie d'activation deE 741. 5 KJ/MOLE). Ces deux étapes sont dues à un seul processus gouverné par la diffusion du carbone. La dernière étape est la précipitation des carbures epsilon ou eta ayant une composition estimée de l'ordre de FE#2#. #4C et s'effectue avec une énergie d'activation de 121. 51. 5 KJ/Mole. La décomposition de la phase austénitique se fait à l'ambiante au cours du chargement cathodique en hydrogène dans un milieu acide à faible densité de courant. La transformation martensitique observée est attribuée à la déformation sous contrainte de la phase austénitique par absorption de l'hydrogène. Aucun hydrure ou phase hexagonale epsilon n'apparait. La distribution du carbone dans la phase martensitique induite ressemble à celle d'un alliage trempé et vieillie avec disparition totale des atomes de carbone isolés dans la solution solide
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Bloch, Elias Morgan. "Diffusion Kinetics of Lutetium and Hafnium in Garnet and Clinopyroxene: Experimental Determination and Consequences for ¹⁷⁶LU-¹⁷⁶HF Geochronometry." Diss., The University of Arizona, 2013. http://hdl.handle.net/10150/311299.
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The ¹⁷⁶Lu-¹⁷⁶Hf and ¹⁴⁷Sm-¹⁴³Nd decay systems have been extensively used as geochronological tools to determine ages from garnet (Grt) - whole rock (WR) parent-daughter isotopic ratios; however, the ¹⁷⁶Lu-¹⁷⁶Hf age of garnet is almost always found to be significantly older than the ¹⁴⁷Sm-¹⁴³Nd age determined from the same aliquots. This dissertation presents new experimental diffusion data for Lu and Hf in garnet, and numerical simulations using these data, which explain these age discrepancies and also show that Grt-WR ¹⁷⁶Lu-¹⁷⁶Hf isochrons do not generally yield ages which correspond to an unambiguous temporal event in the evolutionary history of the host rocks. This is a result of (a) partial or complete retention of very slow-diffusing radiogenic ¹⁷⁶HF produced during prograde heating, and (b) the lower closure temperature of Lu relative to Hf; these complexities do not affect the interpretation of Grt-WR isochrons based on the ¹⁴⁷Sm-¹⁴³Nd system. In addition, the diffusion kinetic properties of Hf in clinopyroxene were experimentally determined in order to address the age controversy of the shergottite suite of Martian meteorites (~200 Ma ages determined by ¹⁷⁶Lu-¹⁷⁶Hf, ¹⁴⁷Sm-¹⁴³Nd, and various other decay systems as opposed to a ~4 Ga whole rock Pb-Pb age). This was achieved by calculating the timescales needed to re-equilibrate Hf isotopes in clinopyroxene (the primary host of rare earth elements amongst the minerals used to compose the ¹⁷⁶Lu-¹⁷⁶Hf isochrons) with the surrounding matrix at the peak- and post-shock P-T conditions likely to have been experienced by the shergottites. It is concluded that, contrary to the earlier suggestions, impact heating is highly unlikely to have significantly reset the ¹⁷⁶Lu-¹⁷⁶Hf ages of these Martian samples. These calculations are bolstered by the nature of measured Cr and Fe-Mg concentration profiles across olivine-melt boundaries, and Ti profiles across clinopyroxene-maskelynite interfaces in the shergottite RBT-04262. The lack of any evidence of diffusion in the measured concentration profiles, coupled with the qualitative incompatibility of the measured crystal-melt fractionation at these interfaces with the nature of fractionation expected from equilibrium partitioning, provides strong evidence that no substantial chemical exchange took place between the solid and melt phases during peak-shock P-T conditions.
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Yihunie, Tadesse. "Chemical Th-U-total Pb isochron ages of zircon and monazite from granitic rocks of the Negele area, southern Ethiopia." Dept. of Earth and Planetary Sciences, Nagoya University, 2003. http://hdl.handle.net/2237/7624.
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Kaufmann, Tina K. [Verfasser], and T. [Gutachter] Meigen. "Validierung der CLAD-Technik beim Muster-ERG: Entfaltung transienter Muster-ERG-Antworten nach schneller Reizung mit nicht-isochronen Stimuli / Tina K. Kaufmann. Gutachter: T. Meigen." Würzburg : Universität Würzburg, 2013. http://d-nb.info/1102825727/34.
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Kanaki, Kalliopi. "Electric Field and Drift Characteristics Studies for the Multiwire Chambers of the Third Plane of HADES." Forschungszentrum Dresden, 2010. http://nbn-resolving.de/urn:nbn:de:bsz:d120-qucosa-29306.
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Aim of this report is the investigation of suitable operational conditions for the drif{}t chambers MDC III installed in the HADES setup. The simulations performed showed that operating the drif{}t chambers in a mode with nearly constant electron drif{}t velocity in a predominant part of the cell allows a more precise and fast tracking. This is particularly important for electrons and positrons; here the invariant dilepton mass must be reconstructed with high precision to get a resolution of $\Delta M/M\approx 1\%$ for the $\omega$ and $\phi$ mass peaks and thus a chance to verify also small in-medium mass shif{}ts. This helps to realize the physics program at HADES which focuses on the search for such mass shif{}ts to get insight into the in-medium behaviour of hadrons in dense strongly interacting matter.
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Kanaki, Kalliopi. "Electric Field and Drift Characteristics Studies for the Multiwire Chambers of the Third Plane of HADES." Forschungszentrum Rossendorf, 2003. https://hzdr.qucosa.de/id/qucosa%3A21758.
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Aim of this report is the investigation of suitable operational conditions for the drif{}t chambers MDC III installed in the HADES setup. The simulations performed showed that operating the drif{}t chambers in a mode with nearly constant electron drif{}t velocity in a predominant part of the cell allows a more precise and fast tracking. This is particularly important for electrons and positrons; here the invariant dilepton mass must be reconstructed with high precision to get a resolution of $\Delta M/M\approx 1\%$ for the $\omega$ and $\phi$ mass peaks and thus a chance to verify also small in-medium mass shif{}ts. This helps to realize the physics program at HADES which focuses on the search for such mass shif{}ts to get insight into the in-medium behaviour of hadrons in dense strongly interacting matter.
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CHABRERIE, CHRISTIAN. "De l'utilisation des recuits isothermes et isochrones pour la caracterisation de structures mos irradiees. Application aux cinetiques des effets post - irradiation dans differents contextes (spatial, accelerateurs) et normes d'essais." Paris 7, 1997. http://www.theses.fr/1997PA077021.
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Notre contribution porte sur la mise au point d'une methodologie d'utilisation des recuits isothermes et isochrones pour la caracterisation des transistors mos (metal - oxyde - semi-conducteur) des composants electroniques irradies. Nous etudions les cinetiques de guerison des effets post-irradiation et la modelisation des phenomenes de guerison actives par la temperature. Ceci permet de comprendre les mecanismes physiques de base qui ont conduit a la definition des procedures de test normalisees. Les domaines d'application sont nombreux (spatial, militaire, accelerateurs pour la physique des hautes energies, nucleaire civil et robotique en milieu hostile). Nous commencons en rappelant le contexte de notre etude et en presentant les actuelles procedures de test normalisees (tm1019. 4 et bs22900) utilisees pour la qualification des circuits integres. Nous passons ensuite en revue les differentes theories des phenomenes actives par la temperature. Le lien entre les fondements des procedures normalisees et les phenomenes thermiquement actives est mis en evidence. A partir de cette analyse, nous proposons une nouvelle approche, principalement fondee sur l'utilisation de recuits isochrones. Au cours de ce travail, nous avons developpe deux outils dans ce but : ? le premier outil est logiciel, c'est un programme de simulation numerique pour des phenomenes thermiquement actives. ? le second est constitue de bancs specifiques de recuits automatises (en particulier isochrones), que nous avons mis au point. Les applications et les resultats sont ensuite decomposes en quatre temps : ? le premier presente les resultats de simulations effectuees grace a notre code de calcul, ? le deuxieme concerne les resultats experimentaux obtenus sur des oxydes minces de differentes technologies durcies et leur application a l'etude des oxydes de grille des transistors, ? le troisieme developpe des resultats sur les oxydes epais des technologies non durcies et leurs consequences sur les courants de fuite lateraux dus aux structures mos parasites des composants du commerce, ? le quatrieme etudie les evolutions post-irradiation des etats d'interface pendant les recuits isochrones. Nous concluons par un certain nombre de recommandations quant aux methodes de test des composants electroniques apres stress. L'utilite des recuits isochrones (tres rapides) comme premiers tests, est demontree. Les informations qu'ils apportent se revelent nettement plus precises que celles que l'on pourrait obtenir par une serie de recuits isothermes.
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Gallegati, Mattia. "Generazione di isocrone ed elaborazione di indicatori statistici con strumenti NoSql in ambiente BigData." Master's thesis, Alma Mater Studiorum - Università di Bologna, 2016.
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L'elaborato propone l'analisi e la riprogettazione di un'applicazione di calcolo di dati statistici inferiti sulla base di mappe geografiche isocrone, isometriche e circolari tramite l'utilizzo di strumenti non relazionali (NoSQL).
L'informatica e l'analisi del tessuto morfologico,economico e geografico del territorio si troveranno qui a stretto contatto ed entrambi risulteranno elementi imprescindibili ai fini dello sviluppo dell'applicativo finale.
Il lavoro espone una lunga analisi di molti strumenti NoSQL attualmente disponibili e l'utilizzo approfondito di Neo4j e MongoDb leader nel mondo non relazionale.
Durante lo sviluppo apparirà necessaria l'implementazione di un nuovo algoritmo per il calcolo delle isocrone che si aggiungerà all'insieme di strumenti già disponibili nel mondo non relazionale.
Il risultato finale sarà un applicativo in grado di migliorare del 80% le prestazioni proposte dal precedente strumento, sviluppato con strumenti relazionali.
Saranno garantite completezza, flessibilità, scalabilità e facilità di integrazione all'interno di qualsiasi contesto.
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Manjate, Vicente Albino. "Geocronologia da região de Gondola-Nhamatanda (Centro de Moçambique)." Universidade de São Paulo, 2012. http://www.teses.usp.br/teses/disponiveis/44/44141/tde-21122012-085416/.
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A região de Gondola-Nhamatanda localiza-se na parte limítrofe entre as províncias de Manica e Sofala, centro de Moçambique. Ela está geologicamente inserida no complexo de Bárue (Grupo de Chimoio) e na cobertura fanerozoica. O Complexo de Bárue é composto pelos Grupos supracrustais de Macossa e Chimoio intrudidos por rochas plutônicas de várias composições. Enquanto que a cobertura fanerozoica consiste de sedimentos terrestres e rochas vulcânicas associadas pertencentes ao Supergrupo do Karoo e à sequências do rifte Este Africano. A área de trabalho foi estudada em termos de petrografia; geoquímica de elementos maiores, traço e de terras raras; geocronologia e geologia isotópica pelos métdos U -Pb em zircão, Rb-Sr e Sm-Nd em rocha total e Rb-Sr em minerais para o granito de Inchope, quartzo-sienito do monte Chissui e fonolito do monte Xiluvo. Este estudo permitíu determinar os litotipos que intrudiram o grupo supracrustal de Chimoio , suas idades de cristalização e de diferenciação dos magmas que formaram seus protólitos e ainda o enquadramento tectônico. As rochas estudadas são basicamente calci -alcalinas com variações de meta à peraluminoso para os granitoides e quartzo-sienito e peralcalino para o fonolito do monte Xiluvo. Os granitoides do grupo de Chimoio foram cristalizados no Mesoproterozoico (idades U-Pb e Rb-Sr) a partir de protólitos Paleoproterozoicos (\'T IND.DM\' = 1,7 - 2,3 Ga); por sua vez, as rochas vulcânicas (fonolitos) do monte Xiluvo cristalizaram rápidamente no Câmbrico (idade Rb-Sr) dum protólito do Neoproterozoico-Câmbrico (\'T IND.DM\' = 0,54 - 0,56 Ga). Os dados isotópicos obtidos no presente estudo sugerem que as rochas do cinturão de Moçambique foram geradas por fusão parcial que provavelmente envolveu mistura ( valores negativos de ?Nd ) da crosta arqueana / paleoproterozoica e magma mesoproterozoico a 1100 Ma e sofreram retrabalhamento marcado pela aglutinação do Gondwana (orogenia Pan-Africana) e tafrogênese marcada pela fraturação do Gondwana (Rifte Este Africano ).The region of Gondola-Nhamatanda is located at the border between the provinces of Manica and Sofala, central part of Moçambique. It is geologically inserted in the Bárue complex and the Phanerozoic cover. The Bárue complex is composed of the Macossa and Chimoio supracrustal groups intruded by plutonic rocks of various compositions, whereas the Phanerozoic cover consists of terrestrial sediments and volcanic rocks belonging to the Karoo Super-group and East African Rift Sequences. The work area was studied in terms of petrography; geochemistry of major elements, trace and rare earth elements; geochronology and isotope geology by the methods U -Pb in zircon, Rb-Sr and Sm-Nd in whole rock and Rb-Sr in minerals for the Inchope granite, Chissui mountain Quartzo-sienito and Xiluvo mountain phonolite. This study allowed to determine the lithotypes that intruded the Chimoio supracrustal group, its crystallization ages and the differentiation ages of the magmas that formed the protoliths and the tectonic framework. The studied rocks are basically calc-alkaline varying from meta to peraluminous for the granitoids and quartz-sienite and peralkaline for the mount Xiluvo phonolite. The Chimoio Group granitoids had been crystallized in the Mesoproterozoic (U-Pb and Rb-Sr ages) from Paleoproterozoic protoliths (\'T IND.DM\' = 1.7 - 2.4Ga); on the other hand, the volcanic rocks (phonolites) of the Xiluvo mount had crystallized fast in the Cambrian (Rb-Sr age) from a Neoproterozoic-Cambrian protolith (\'T IND.DM\' = 0.54 - 0.56Ga). The isotopic data, in the present study , suggest that the rocks of the Mozambique belt had been generated by partial melting that probably involved the mixture of the archean/paleoproterozoic crust and the Mesoproterozoic magma at 1100Ma and had suffered reworking marked by the Gondwana amalgamation (Pan-African orogeny) and extensional processes marked by the Gondwana break up (East African Rift).
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Chouikha, Raouf. "Aspects des fonctions elliptiques. \\ Solutions périodiques d'équations différentielles.\\ Métriques pseudo-cylindriques. \\ Problèmes isopérimètriques plans." Habilitation à diriger des recherches, Université de Rouen, 2003. http://tel.archives-ouvertes.fr/tel-00003633.
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(\bf RESUME) \footnote(Les références sont celles de la liste des publications.) \end(center) * Dans la première, on examine les propriétés de la fonction elliptique\\ $\wp(z,\omega,\omega')$\ de Weierstrass et les fonctions \ $\theta(v,\tau)$ \ classiques, à la lumière d'un nouveau développement trigonométrique. On détermine explicitement les coefficients en fonction de \ $\tau$, qui sont en fait des fonctions hypergéométriques. (\it [P1], [P6]). \\ Cela permet en particulier une nouvelle construction de la théorie des fonctions elliptiques et de retrouver certaines propriétés. Notamment, celle concernant la fonction zeta de Jacobi \ $Zn(z,k).$\ Aussi, on met en évidence des relations modulaires entre ces coefficients. \ (\it [P7], [P19], [P22]). * Dans la deuxième partie, on s'intéresse aux solutions\ périodiques \ de \ certaines\ équations\ différentielles\ ordinaires et, plus précisèment à la croissance de la fonction période dépendant de l'énergie et, aux conditions de sa monotonie. Nous mettons en évidence une nouvelle condition suffisante. (\it [P5]). On montre en particulier que tous les critères connus - à savoir ceux de Chow, Schaaf Chicone et Rothe - ne sont pas optimaux. (\it [P8]).\\ On s'intéresse aussi à la monotonie de la période du système de Liénard avec un centre à l'origine.On donne en particulier une preuve plus simple d'un résultat de Christopher et Devlin. (\it [T30] ) En utilisant des séries trigonométriques, on montre l'existence de solutions périodiques pour une équation de type Duffing perturbée. (\it [P10], [P12]).\\ Enfin, on utilise avec succès une méthode de Farkas concernant la controllabilité de la période pour montrer l'existence d'une solution périodique de l'équation de Liénard perturbée. (\it [P13] ). * Dans la troisième partie, nous mettons en évidence les propriétés des courbures riemannienne et de Ricci de certaines métriques à courbure scalaire constante positive, ainsi que leurs singularités. (\it [P3], [P4]).\\ Ces métriques en nombre fini sont appelées pseudo-cylindriques. De plus, elles ont une courbure harmonique et une courbure de Ricci non paralléle, et sont solutions du problème de Yamabe singulier sur la sphère standard privée de deux points\ $S^n -\(p_1,p_2\).$ \ On examine aussi leurs propriétés asymptotiques. De plus, pour certaines valeurs de \ $n \ =3,4$\ ou\ $6$ \ on peut déterminer ces métriques explicitement. On s'intéresse aussi au problème d'existence de métriques tordues de A. Derdzinski. (\it [P11], [P15]). * Enfin, dans la dernière partie, on considère des inégalités isopérimètriques de type Bonnesen en rapport avec des conjectures de P. Lévy et de X.M. Zhang sur des polygones plans. Nous proposons en particulier une conjecture plus générale.\ (\it [P2], [P9], [P18]).
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ONeal, Ryan J. "Seismic and Well Log Attribute Analysis of the Jurassic Entrada/Curtis Interval Within the North Hill Creek 3D Seismic Survey, Uinta Basin, Utah, A Case History." BYU ScholarsArchive, 2007. https://scholarsarchive.byu.edu/etd/1025.
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3D seismic attribute analysis of the Jurassic Entrada/Curtis interval within the North Hill Creek (NHC) survey has been useful in delineating reservoir quality eolian-influenced dune complexes. Amplitude, average reflection strength and spectral decomposition appear to be most useful in locating reservoir quality dune complexes, outlining their geometry and possibly displaying lateral changes in thickness. Cross sectional views displaying toplap features likely indicate an unconformity between Entrada clinoforms below and Curtis planar beds above. This relationship may aid the explorationist in discovering this important seismic interval. Seismic and well log attribute values were cross plotted and have revealed associations between these data. Cross plots are accompanied by regression lines and R2 values which support our interpretations. Although reservoir quality dune complexes may be delineated, the Entrada/Curtis play appears to be mainly structural. The best producing wells in the survey are associated with structural or stratigraphic relief and the thickest Entrada/Curtis intervals. Structural and stratigraphic traps are not always associated with laterally extensive dune complexes. Time structure maps as well as isochron maps have proven useful in delineating the thickest and/or gas prone portions of the Entrada/Curtis interval as well as areas with structural and stratigraphic relief. We have observed that the zones of best production are associated with low gamma ray (40-60 API) values. These low values are associated with zones of high amplitude. Thus, max peak amplitude as a seismic attribute may delineate areas of higher sand content (i.e. dune complexes) whereas zones of low amplitude may represent areas of lower sand content (i.e. muddier interdune or tidal flat facies). Lack of significant average porosity does not seem to be related to a lack of production. In fact, the best producing wells have been drilled in Entrada/Curtis intervals where average porosity is near 4 %. There are however zones within the upper portion of the Entrada/Curtis that are 40 ft. (12.2 m) thick and have porosities between 14% and 20%. By combining derived attribute maps with observed cross plot relationships, it appears that the best producing intervals within the Entrada/Curtis are those associated with high amplitudes, API values from 40-60 and structural relief.
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Sigwalt, Michel. "Nouvelle formulation de la diffraction impulsionnelle application au couplage radiatif /." Grenoble 2 : ANRT, 1987. http://catalogue.bnf.fr/ark:/12148/cb37609925c.
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Ries, Markus. "Nonlinear momentum compaction and coherent synchrotron radiation at the Metrology Light Source." Doctoral thesis, Humboldt-Universität zu Berlin, Mathematisch-Naturwissenschaftliche Fakultät I, 2014. http://dx.doi.org/10.18452/16979.
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Das Thema der vorgelegten Dissertation ist der quasi-isochrone Betrieb der Metrology Light Source zur Erzeugung kurzer Elektronenpakete mit der damit verbundenen Emission von kohärenter Sychrotronstrahlung. Die Metrology Light Source wurde schon in der Planungsphase auf den quasi-isochronen Betrieb ausgelegt. Es stehen Quadrupol-, Sextupol- und Oktupolmagnete zur Verfügung, um die drei führenden Ordnungen des sogenannten momentum compaction factors zu kontrollieren. Der Schwerpunkte der Arbeit ist nichtlineare, longitudinale Strahldynamik, insbesondere die sogenannten "alpha-buckets". Der Vergleich zwischen analytischen Ansätzen, numerischen Simulation und experimentellen Daten wird vorgestellt und diskutiert. Desweiteren wurde die Stromlimitierung durch die Bursting-Instabilität an der Metrology Light Source untersucht. Der Großteil der Messungen ist dabei an der Metrology Light Source durchgeführt worden mit komplementären Messungen am Elektronenspeicherring BESSY II.The subject of this thesis is the operation of an electron storage ring at a low momentum compaction to generate short electron bunches as a source for coherent synchrotron radiation. For this purpose the Metrology Light Source is ideally suited, as it is the first light source designed with the ability to adjust the three leading orders of the momentum compaction factor by quadrupole, sextupole and octupole magnets. Therefore, new opportunities to shape the longitudinal phase space arise. Focus will be put on beam dynamics dominated by nonlinear momentum compaction, in particular the generation of a new bucket type "alpha-buckets" and possible applications. Relation of analytical theory, numerical simulations and experimental data will be presented and discussed. In addition, the current limitation due to the bursting instability at the Metrology Light Source bunches will be investigated. The majority of measurements were conducted at the Metrology Light Source complemented by measurements at the BESSY II storage ring.
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Bouchet, Gilles. "Mélanges magmatiques et genèse des granitoïdes calco-alcalins : l'exemple du complexe tonalo-granodioritique de Bono (Sardaigne septentrionale) : étude pétrologique et géochimique." Saint-Etienne, 1992. http://www.theses.fr/1992STET4022.
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Le complexe intrusif de Bono (association calco-alcaline corso-sarde, Sardaigne septentrionale) se caractérise par la mise en place successive de 3 intrusions de nature pétrographique différente faisant apparaitre une structure de type apparemment concentrique. De la périphérie vers le centre du complexe, on distingue l'intrusion tonalitique différenciée de Burgos, l'intrusion granodioritique à amphibole de Bottida puis l'intrusion granodioritique à biotite d'Emauru. Les enclaves microgrenues sombres constituent par leur abondance un trait caractéristique des granitoïdes du complexe de Bono, chaque population d'enclaves se caractérisant par un rapport FEOT/MGO constant. Cette association composite acide-basique (roche hôte-enclave) est interprétée en terme de mingling (mélange incomplet par opposition au mixing lorsque l'homogénéisation est complète). Les travaux antérieurs sur les granitoïdes de l'association calco-alcaline du batholite montrent que le mélange magmatique y constitue un processus largement répandu. Les enclaves de chaque intrusion, se caractérisent par 2 populations de cristaux : l'une relique ante-mélange, appartenant au magma basique : CPX+OPX+PLAP dans les enclaves de Burgos, CPX+PL dans les enclaves de Bottida, PL+HB brune dans les enclaves d'Emauru, est interprétée en terme de différenciation ante-mélange du liquide basique. La seconde population, volumétriquement prédominante et similaire à celle de la roche hôte correspondante, est synchroné à post-mélange. Dans le liquide basique générateur des enclaves de Burgos, les couples CPX-OPX sont cristallisés à 900-950 oc dans des conditions de PH2O relativement élevées. Dans les enclaves d'Emauru, les conditions de cristallisation de la HB sont de 850-920 oc pour 6-7 Kbar, soit environ 21 à 25 km de profondeur. De plus, la présence de reliques de cumulats dans certaines enclaves de Burgos en particulier, permet d'invoquer la différenciation par cristallisation fractionnée d'un basalte alumineux (HAB) en position basi-crustale. Ce processus se marque par un très net enrichissement en eau du HAB indépendamment du processus de mélange : de 1 à 4% d'eau dans Burgos, jusqu'à 5% dans Emauru. Nous observons ainsi un contraste très net entre la paragénèse ante-mélange du liquide basique de Burgos où elle est anhydré et celle des enclaves d'Emauru où elle est hydratée. Cet enrichissement en fluide qui se traduit par l'apparition de la HB brune, induit de nombreuses répercutions pétrologiques, en particulier l'arrêt de l'enrichissement en fer du liquide basique
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Blaschke, Stefan. "Zeitwahrnehmung in isochronen Sequenzen." Doctoral thesis, 2009. http://hdl.handle.net/11858/00-1735-0000-0006-AD6C-9.
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Wu, Min-Hung, and 吳旻鴻. "cell competition algorithm based on isochronal evolution." Thesis, 2005. http://ndltd.ncl.edu.tw/handle/15834911062347266348.
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碩士國立臺灣大學
醫學工程學研究所
93
Boundary extraction of multiple targets in a sonogram can help clinicians find out perceptible objects, save time for sinologists and be used for training. Moreover, it plays an essential role in developing computer-aided diagnosis systems. Because of the intrinsic properties in ultrasonic images, such as low contrast, high noises, speckle, artifacts and so on, it is generally difficult to automatically identify the boundaries of the images. These intrinsic properties make the desired edges blurred and deteriorate the discriminability of the boundaries. In order to alleviate the influence of these physical problems and mitigate the over-segmentation of targets, we proposed a new segmentation algorithm, which was a cell competition algorithm based on isochronal evolution. The proposed method composed of two steps. First, we used the image processing filters such as Gaussian filter and Sobel filter to smooth the images and enhance the boundary information. After that, we used the Watershed transformation to over-segment the images to capture all possible boundaries and generate the initial cells. After completion of pre-segmentation, cell competition was performed following the criteria of isochronal evolution, which were imposed on regions when they were growing and competing with one another. Each region grew with its own viscosity which consisted of local similarity and global variation. Local similarity serves as the primary force for region expansion, whereas global variation plays the role of expansion hindrance. The experimental results on the clinical ultrasound images showed that our algorithm could identify all objects of interest reasonably well. Moreover by adjusting the beginning time, we can alleviate the over-segmentation for malignant lesions. The algorithm was validated by comparing with manually outlined boundaries. The results showed that the differences between the boundaries derived by the proposed method and the hand-outlined boundaries were within the range of the differences among different observers.
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Hug, Florian. "Erhöhung der Energieschärfe des Elektronenstrahls am S-DALINAC durch nicht-isochrones Rezirkulieren." Phd thesis, 2013. https://tuprints.ulb.tu-darmstadt.de/3469/1/Diss_Online.pdf.
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In dieser Arbeit wird die longitudinale Teilchendynamik des Elektronenstrahls im supraleitenden, rezirkulierenden Elektronenbeschleuniger S-DALINAC detailliert untersucht und systematisch optimiert. Ziel ist dabei eine Erhöhung der Energieschärfe des Elektronenstrahls, um die Präzision kernphysikalischer Elektronenstreuexperimente zu steigern. Im Gegensatz zur geläufigen Konvention an Linearbeschleunigern wird hierzu eine Beschleunigung auf der Flanke des Hochfrequenzfeldes zusammen mit einer nicht-isochronen Teilchendynamik in den Rezirkulationsstrecken verwendet. Durch optimale Anpassung des longitudinalen Betatronphasenvorschubs kann eine Unterdrückung des Einflusses der Regelungsgenauigkeit der supraleitenden Hochfrequenzstrukturen auf die Energieschärfe erreicht werden, so dass die resultierende Energieschärfe letztlich unabhängig von Fehlerbeiträgen der supraleitenden Beschleunigungsstrukturen im Hauptbeschleuniger ist.
Zur Umsetzung wurden im Rahmen dieser Arbeit zuerst Simulationsrechnungen im longitudinalen Phasenraum durchgeführt, um den optimalen Arbeitspunkt für den S-DALINAC einzugrenzen. Die Ergebnisse dieser Simulationen lassen dabei neben einer höheren Energieschärfe des Elektronenstrahls auch eine größere Stabilität gegenüber Fehlereinflüssen erwarten. In einem weiteren Schritt musste die Strahldynamik in den Rezirkulationsbögen des S-DALINAC für einen nicht-isochronen Strahltransport mit Hilfe weiterer Simulationsrechnungen optimiert werden, bevor diese Bögen gemäß der Berechnungen umgestaltet wurden.
Die Quantifizierung der durchgeführten Änderungen erfolgte durch Flugzeitmessungen mit einem eigens entwickelten Messaufbau, der in dieser Arbeit präsentiert wird. Zum Abschluss konnte der optimale Arbeitspunkt am S-DALINAC mit Hilfe systematischer Messungen aufgefunden und eingestellt werden. Die Energieschärfe des nicht-isochron rezirkulierten Strahls war mit 1.23 EXP -4 um einen Faktor 5.4 besser als diejenige mit isochron rezirkuliertem Strahl. Dieser Wert stellt gleichzeitig die bislang höchste gemessene Genauigkeit für einen rezirkulierten Strahl am S-DALINAC dar.
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Chen, Yi-ming, and 陳一銘. "A Study of the Relationships between Isochrone Alternatives for Theme Parks and Marketing Mix: A Case Study of Janfusun Fancyworld." Thesis, 2005. http://ndltd.ncl.edu.tw/handle/69816699540534793607.
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碩士大葉大學
休閒事業管理學系碩士班
93
The topology of traffic linkages between original and destination have influences on the frequency, durations, motivations and costs of a tour. Previous researches concluded that distance between original and destination will change the demands of the consumers and the supplies of the destination. This research applied the Isochrone method integrated within Geography Information System (GIS) to find out if there existed a significant difference between the acceptance of eight marketing mixes(including four current mixes and four simulating mixes proposed in this research) of Janfusun Fancy World, a famous theme park in the middle of Taiwan, for consumers and the distance from originals to destination for consumers. Four isochrone areas were analyzed by different travel hours and a structural questionnaire were applied with convenience sampling method in the four areas. The research found that the "Promotion" and "Place" had significant differences between difference isochrones. This founding reflects that the combinations of marketing mixes should take the traveling distance as a main consideration. The promotion of long distance-traveling consumers to a theme park could have an overnight suit while the short distance-traveling consumers with a ticket-fee discount. Finally the findings carry on the integrated discussion, and puts forward the correlated suggestions.
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Guyot, Brendan M. "Effect of cold working and isochronal annealing processing parameters on special grain boundary fractions in commercial purity nickel." 2003. http://hdl.handle.net/1993/19917.
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Blaschke, Stefan [Verfasser]. "Zeitwahrnehmung in isochronen Sequenzen : ein Vergleich verschiedener Modelle zum Einfluss des Kontextes auf die Wahrnehmungsleistung / vorgelegt von Stefan Blaschke." 2009. http://d-nb.info/999494937/34.
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Kaufmann, Tina K. "Validierung der CLAD-Technik beim Muster-ERG: Entfaltung transienter Muster-ERG-Antworten nach schneller Reizung mit nicht-isochronen Stimuli." Doctoral thesis, 2013. https://nbn-resolving.org/urn:nbn:de:bvb:20-opus-97377.
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Einleitung:
Steady-State- Muster-ERGs (PERGs) werden in der Glaukomfrühdiagnostik angewandt. Da die transienten PERG-Komponenten N35, P50 und N95 unter schnellen Reizbedingungen nicht zu erkennen sind, können bisher keine Aussagen über die Beteiligung einzelner Retinaschichten an der Reizantwort gemacht werden. Mit der Deconvolution-Methode (CLAD) wurden 2004 akustisch evozierte transiente Antworten aus hochfrequenten Messungen entfaltet. In dieser Arbeit wird CLAD beim PERG validiert um herauszufinden, ob bei Messungen mit hohen Reizfrequenzen deutliche transiente Antworten entfaltet werden.
Methodik:
Es wurden 3 Reizbedingungen mit nicht-isochronen Stimuli der mittleren Frequenz 16,7 rps verglichen. Der Abstand zwischen 2 Stimuli variierte zwischen 15 und 105 ms, 30 und 90 ms oder 45 und 75 ms, der mittlere Abstand betrug jedoch immer 60 ms. Als Referenz wurden konventionelle transiente (1,4 rps) und Steady-State-Messungen (16,7 rps) durchgeführt. Um sie zu validieren, wurden in einem zweiten Schritt aus den transienten CLAD-Steady-State-Antworten synthetisiert und diese mit der Steady-State-Referenzmessung verglichen.
Ergebnisse:
Die große Übereinstimmung der synthetisierten Steady-State-Antworten mit der Referenzmessung im Bezug auf Amplitude und –Kurvenform bestätigte, dass die entfalteten transienten Antworten „trotz“ Abweichungen von konventionellen PERG-Antworten plausibel sind. Allerdings hatte der konkrete Stimulusabstand Einfluss auf die PERG-Antwort: die Amplituden der 3 CLAD-Reizbedingungen wichen signifikant voneinander ab.
Diskussion:
Diese Studie zeigte, dass durch CLAD transiente Reizantworten aus Messungen hoher Frequenz gewonnen werden können. Ob der Einsatz von CLAD Vorteile in der Glaukomfrühdiagnostik erbringt und der exakte retinale Ursprung der Antwortkomponenten ist in künftigen Studien zu validieren. Durch CLAD könnte es in Zukunft möglich werden, auf elektrophysiologischem Wege den Beitrag einzelner Retinaschichten bei Retinapathologien genauer aufzuzeigen.
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Cournoyer, Jean-Philippe. "Courbe de rotation de la galaxie à partir de la photométrie d'amas situés à la périphérie du disque." Thèse, 2004. http://hdl.handle.net/1866/14757.
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