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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.
561

Unfolding based verification of concurrent infinite-state systems

Trần, Thế Quang 19 June 2009 (has links)
Nous proposons une technique de dépliage pour vérifier les systèmes concurrents infinis bien structurés. Certaines propriétés d'intérêt comme la bornitude, la couverture et la terminaison sont décidables grâce à la bonne structure de ces systèmes. D'autre part, le dépliage réduit efficacement l'explosion combinatoire en exploitant l'ordre partiel entre les événements des systèmes concurrents. Nous proposons une modélisation par structure d'événements pour des systèmes bien structurés élémentaires, tels les compteurs et les files de communication. Le dépliage d'un réseau de structures d'événements étant une structure d'événements, nous proposons ensuite une approche hiérarchique à la modélisation et à la vérification des systèmes, qui préserve la bonne structure. Enfin, nous proposons une technique d'élimination des événements redondants. La mise en œuvre de notre approche dans l'outil ESU nous permet de conclure à son efficacité. / We propose an unfolding technique for verifying concurrent infinite-state systems that are well-structured. Some properties of interest such as boundedness, coverability and termination are decidable thanks to the well-structure of these systems. Moreover, the unfolding effectively reduces the combinatorial explosion by exploiting the partial order between events of concurrent systems. We propose a modelization using event structures for basic well-structured systems, such as counters and communication channels. As the unfolding of a synchronized product of event structures is an event structure, we obtain a hierarchical approach to modeling as well as to verifying systems, which preserves the well-structure. Finally, we propose a technique for eliminating redundant events. The implementation of our approach in the ESU tool allows us to conclude on its efficiency.
562

Vypořádání společného jmění manželů / Community property of spouses and its settlement

Muzikář, Martin January 2012 (has links)
This thesis is primarily based on analysis of practice of the courts and papers, which afford the deeper insight into the relatively short legislation. Certainly could be adopted more particular legislation of the settlement of community property of spouses, decisions on such matters but may not look like as a "juristic machine", which is limited by the particular provisions of law. A key role is played by the legal conclusion of an experienced lawyer who, after analysis of the situation, adjudge in the spirit of the flexible provisions of the law. During the work on this thesis, I therefore had to deal with the different views on the problem and with the obsolete ideas. The work responds to a relatively large number of interpretative differences with the declaration of my own opinion on the problem supported by the relevant arguments. Today we face a very anxious fact that the number of marriages since 1989 is sharply decreasing. This issue is further analyzed in the first chapter where I pointed to some stimuli, which could weaken this trend. It could be very beneficial to realize a sociological research on the factors that cause this adverse trend. In the future it will be interesting to see how these numbers will be affected by the new legislation (i. e. law No. 89/2012 Coll., Civil Code). I...
563

Computational Analysis of Molecular Recognition Involving the Ribosome and a Voltage Gated K+ Channel

Andér, Martin January 2009 (has links)
Over the last few decades, computer simulation techniques have been established as an essential tool for understanding biochemical processes. This thesis deals mainly with the application of free energy calculations to ribosomal complexes and a cardiac ion channel. The linear interaction energy (LIE) method is used to explore the energetic properties of the essential process of codon–anticodon recognition on the ribosome. The calculations show the structural and energetic consequences and effects of first, second, and third position mismatches in the ribosomal decoding center. Recognition of stop codons by ribosomal termination complexes is fundamentally different from sense codon recognition. Free energy perturbation simulations are used to study the detailed energetics of stop codon recognition by the bacterial ribosomal release factors RF1 and RF2. The calculations explain the vastly different responses to third codon position A to G substitutions by RF1 and RF2. Also, previously unknown highly specific water interactions are identified. The GGQ loop of ribosomal RFs is essential for its hydrolytic activity and contains a universally methylated glutamine residue. The structural effect of this methylation is investigated. The results strongly suggest that the methylation has no effect on the intrinsic conformation of the GGQ loop, and, thus, that its sole purpose is to enhance interactions in the ribosomal termination complex. A first microscopic, atomic level, analysis of blocker binding to the pharmaceutically interesting potassium ion channel Kv1.5 is presented. A previously unknown uniform binding mode is identified, and experimental binding data is accurately reproduced. Furthermore, problems associated with pharmacophore models based on minimized gas phase ligand conformations are highlighted. Generalized Born and Poisson–Boltzmann continuum models are incorporated into the LIE method to enable implicit treatment of solvent, in an effort to improve speed and convergence. The methods are evaluated and validated using a set of plasmepsin II inhibitors.
564

Fetal Anomalies : Surveillance and Diagnostic Accuracy of Ultrasound and Magnetic Resonance Imaging

Amini, Hashem January 2010 (has links)
The aims were to investigate the accuracy of ultrasound in diagnosis of structural fetal anomalies with special focus on false positive findings (I), to evaluate the additional value of second trimester fetal MRI on pregnancy management (II-III) and to estimate the ascertainment in the Swedish Birth Defects Registry and incidence of spina bifida and cleft lip/palate (IV). Retrospectively, 328 fetal autopsies were identified where pregnancies were terminated due to ultrasonographically diagnosed fetal anomalies. In 175 (53.4 %) cases ultrasound and fetal autopsy were identical, in 124 (37.8 %) ultrasound was almost correct, in 23 (7.0 %)  ultrasound diagnoses could not be verified, but fetal autopsy showed other anomalies with at least the same prognostic value and in six (1.8 %)  ultrasound diagnosis could not be verified and autopsy showed no or less severe anomalies (I). Prospectively, 29 pregnancies with CNS- (II) and 63 with non-CNS-anomalies (III) were included. In the CNS study MRI provided no additional information in 18 fetuses (62 %), additional information without changing the management in 8 (28 %) and additional information altering the pregnancy management in 3 (10%). In the non-CNS study the corresponding figures were 43 (68 %), 17 (27 %) and three (5 %), respectively. MRI in the second trimester might be a clinically valuable adjunct to ultrasound for the evaluation of CNS anomalies, especially when the ultrasound is inconclusive due to maternal obesity (II) and in non-CNS anomalies in cases of diaphragmatic hernia or oligohydramnios (III). In newborns, the ascertainments of birth defects are relatively high and assessable, but in pregnancy terminations they are lower or unknown. The incidence of newborns with spina bifida has decreased because of an increased rate of pregnancy terminations (>60%). There is room for improvement concerning the reporting of anomalies from terminated pregnancies (IV).
565

Studies of flow duct acoustics with applications to turbocharged engines

Rämmal, Hans January 2009 (has links)
A number of experimental and theoretical studies, performed in the field of technical flow duct acoustics are presented in this thesis. The acoustical methods treated are implemented on turbocharged IC-engines and engine gas exchange system components. A new method based on the well-known two-load technique has been developed. The method was applied to characterise the source data of various piston-engines with non-linear behaviour including a 6 cylinder turbo-charged truck diesel engine. The source characterisation results were compared to the results obtained using the linear two-load technique. It was demonstrated that the new non-linear multi-load technique gives improved results when the source is slightly non-linear. The use of active one-port models has been tested to characterize an air terminal device (ATD) as a source of flow generated noise. In order to predict the noise generation at different operating points of the device a scaling law was derived and verified. In the experimentally derived scaling law a flow speed dependence of 3 was found for the narrow band spectra, corresponding to a dipole-like behavior of the source in the plane wave range. The proposed technique was validated successfully and the results indicated a good prediction of in-duct sound generation by the air terminal device. Sound reflection from hot flow duct openings has been investigated experimentally. The reflection coefficient was measured for flow temperatures up to 500 ºC and jet velocities up to 108m/s. The results have been compared with famous Munt’s theory. It was concluded that at low Mach number and Helmholz number cases the results agree well with the Munt’s model. This was the first experimental validation of the theory for hot flow conditions. Experimental procedures to determine the sound transmission through automotive turbo-charger compressors were developed and described in detail. An overview of a unique turbocharger testing facility established at KTH CICERO in Stockholm is given. The facility can be used to measure acoustic two-port data for turbo-compressors. Results from measurements on a passenger car turbo-compressor are presented and the influence of operating conditions on the sound transmission is discussed. Current wave action models developed in CMT for computation of the gas exchange processes in I.C. engines have been implemented to determine the acoustic wave transmission through the turbo- compressor. The models are validated with the experimental data and the results are presented for different operating conditions of a Volvo passenger car turbo-compressor. / QC 20100809
566

Intervention med responsiva talakter inom AKK hos två deltagare med cerebral pares i Tanzania : en single subject design-studie / Intervention of Responsive Speech Acts Using AAC for Two Participants with Cerebral Palsy in Tanzania : A Single Subject Design-Study

Torstensson, Maja, Vinblad, Elin January 2012 (has links)
I många utvecklingsländer finns en begränsad tillgång på utvecklade AKK-system (Alant, 1999) och ofta även en okunskap kring möjligheterna att arbeta med kommunikationsproblem (Marshall, 1997). I föreliggande studie genomförs intervention i alternativ och kompletterande kommunikation (AKK) för två deltagare med cerebral pares på ett dagcenter i Kilimanjaroregionen, Tanzania. Syftet i föreliggande interventionsstudie är att genom intervention studera och utveckla de i mätsituationerna responsiva talakterna att påkalla uppmärksamhet för att inleda interaktion, acceptera och avfärda samt upprätthålla och avsluta interaktion. Detta sker med hjälp av begreppen ja och nej för att acceptera och avfärda, liksom mer och mindre för att upprätthålla och avsluta interaktion. Studien följer en single subjekt design och insatsen utgörs av två interventionsperioder, bestående av direkt intervention med deltagarna samt utbildning och fortlöpande handledning av personal. Resultaten visar att deltagarna i varierande grad lärde sig att påkalla uppmärksamhet för att inleda interaktion, acceptera och avfärda samt upprätthålla och avsluta interaktion. Det observerades även att deltagarna i högre grad utförde performativa talakter utanför den styrda testsituationen. Områden som vidare diskuteras är bland annat deltagarnas kommunikativa handlingar utifrån The Communication Matrix där en utveckling från prelingvistiska uttrycksätt till användandet av abstrakta symboler synliggjordes hos deltagarna. / In several developing countries there are a limited supply of developed AAC systems (Alant, 1999) whereas a lack of knowledge about the possibilities of working with communication problems (Marshall, 1997). The present study is an intervention study about the introduction of augmentative and alternative communication (AAC) for two participants with cerebral palsy at a day-care centre in the Kilimanjaro Region, Tanzania. The purpose of the intervention study was to develop responsive speech acts to attract attention to initiate interaction, accept and reject interaction, as well as maintain and terminate interaction. This was done using the terms yes and no to accept and reject, and more and less to continue and terminate interaction. The study followed a single subject design consisting of two intervention periods, where direct intervention with the participants and continuing training and guidance for the staff occurred. The results show that the participants in varying degrees, has learned to attract attention to initiate interaction, accept and reject interaction as well as to maintain and terminate interaction. It was also observed that the participants learned to use the performative speech acts outside the controlled test situation. An area further discussed is the participants’ communicative acts as shown in The Communication Matrix, which displayed a development from pre linguistic models of expression to use the abstract symbols.
567

Investigating athletes' retirement from sport : from decision-making to optimal support programmes

Park, Sunghee January 2012 (has links)
This thesis aimed to extend knowledge of athletes’ career transitions through examining athletes’ retirement decision-making process and influence of cultural diversity and organisational culture on the process of career transition. The purpose of Study 1 was to identify the current status of knowledge in the study area through providing a systematic review of the athlete career transition studies. The findings provided up to date knowledge in the study area and suggested potential future research directions. Study 2 aimed to understand Korean tennis players’ career transition out of sport experiences via longitudinal qualitative research. The results indicated that athletes perceived making the retirement decision was difficult process for them and revealed that participants’ experiences were influenced by cultural aspects and sport contexts of Korea. Study 3 focused on exploring the athletes’ retirement decision-making process among Korean tennis players. Results showed that athletes’ leaving from sport decision-making is a complex and multidimensional process, and the transtheoretical model was helpful in explaining athletes’ retirement from sport decision-making. The objective of Study 4 was to explore the processes involved in the development of an athletes’ career transition programme. Results revealed that the organisation might have influence on athletes’ retirement decision and the quality of career transition. Overall, the findings from the current thesis provide advanced useful knowledge on the athlete career transition process, and such knowledge may assist attempts to enhance athletes’ well-being and welfare for during and post-sport life.
568

Kinetics and Mechanism of Cu-Catalyzed Atom Transfer Radical Polymerization

Sörensen, Nicolai 26 May 2015 (has links)
No description available.
569

Terminierungskinetik radikalischer Homo- und Copolymerisationen bis zu hohen Monomerumsätzen / Termination kinetics of free-radical homo- and copolymerisations up to high degrees of monomer conversion

Feldermann, Achim 03 July 2003 (has links)
No description available.
570

Investigations into the Propagation and Termination Kinetics of the Radical Polymerization of Polar Monomers in Aqueous Solution

Schrooten, Jens 24 October 2012 (has links)
Propagations- und Terminierungsgeschwindigkeitskoeffizienten radikalischer Polymerisationen in w&auml;ssriger L&ouml;sung wurden durch Pulslaser-induzierte Polymerisationen und durch chemisch initiierte Polymerisationen bestimmt. Pulslaser-induzierte Polymerisationen wurden von <i>N</i>,2&#8209;Dimethylprop&#8209;2&#8209;enamid, <i>N</i>,<i>N</i>&#8209;Dimethylprop&#8209;2&#8209;enamid, 2&#8209;Methylprop&#8209;2&#8209;enamid und Prop&#8209;2&#8209;enamid durchgef&uuml;hrt. Anschlie&szlig;ende Analyse der Produkte mittels Gr&ouml;&szlig;enausschlusschromatographie erm&ouml;glichte die Bestimmung der Propagationsgeschwindigkeitskoeffizienten. Die beobachtete &Auml;nderung des Propagationsgeschwindigkeitskoeffizienten mit der Monomerkonzentration kann durch die St&auml;rke, mit der innere Rotationen und Vibrationen im &Uuml;bergangszustand des Propagationsschritts gehindert sind, erkl&auml;rt werden. Die Abh&auml;ngigkeit der St&auml;rke der Hinderung von der Monomerkonzentration l&auml;sst sich zur&uuml;ckf&uuml;hren auf sich mit steigendem Monomeranteil verst&auml;rkende intermolekulare Wechselwirkungen der &Uuml;bergangszustandsstruktur mit solvatisierenden Molek&uuml;len. Zur Bestimmung der Aktivierungsvolumina und der Arrhenius-Aktivierungsenergien der Propagation wurden Druck und Temperatur von Umgebungsdruck bis 2&nbsp;000&nbsp;bar beziehungsweise von 10&nbsp;&deg;C bis 80&nbsp;&deg;C variiert. Sowohl die Aktivierungsenergie als auch der Betrag des Aktivierungsvolumens sind im Fall von 2&#8209;Methylprop&#8209;2&#8209;enamid gr&ouml;&szlig;er verglichen mit <i>N</i>,<i>N</i>&#8209;Dimethylprop&#8209;2&#8209;enamid. Diese Beobachtung kann dem Umstand, dass <i>N</i>,<i>N</i>&#8209;Dimethylprop&#8209;2&#8209;enamid keine &alpha;&#8209;Methylgruppe aufweist, zugeschrieben werden. Beide Aktivierungsparameter sind im Fall von <i>N</i>,2&#8209;Dimethylprop&#8209;2&#8209;enamid denen des <i>N</i>,<i>N</i>&#8209;Dimethylprop&#8209;2&#8209;enamid &auml;hnlich. Dies ist unerwartet, da <i>N</i>,2&#8209;Dimethylprop&#8209;2&#8209;enamid eine &alpha;&#8209;Methylgruppe aufweist. Unterschiede zwischen beiden Monomeren hinsichtlich der Konformation der Kohlenstoff&ndash;Kohlenstoff-Doppelbindung relativ zur Kohlenstoff&ndash;Sauerstoff-Doppelbindung k&ouml;nnten diese Beobachtung erkl&auml;ren.<br> Zur Bestimmung von Terminierungsgeschwindigkeitskoeffizienten wurde die Polymerisation durch einen einzelnen Laserpuls initiiert und der Monomer-zu-Polymer-Umsatz anschlie&szlig;end mittels zeitaufgel&ouml;ster Nahinfrarotspektroskopie verfolgt. Die Zeitaufl&ouml;sung ist auf 0.33&nbsp;&mu;s verbessert worden. Wiederholte Einstrahlung von Laserpulsen in Kombination mit nahinfrarotspektroskopischer Analyse liefert Terminierungsgeschwindigkeitskoeffizienten als Funktion des Grades des Monomerumsatzes. Untersuchungen der Terminierungskinetik von Prop&#8209;2&#8209;enamid, 2&#8209;Methylprop&#8209;2&#8209;enamid, <i>N</i>,2&#8209;Dimethylprop&#8209;2&#8209;enamid, <i>N</i>,<i>N</i>&#8209;Dimethylprop&#8209;2&#8209;enamid und 1&#8209;Vinylpyrrolidin&#8209;2&#8209;on wurden, aufgrund des besseren Signal-Rausch-Verh&auml;ltnisses bei hohen Dr&uuml;cken, bei 2&nbsp;000&nbsp;bar durchgef&uuml;hrt. Weitere Messungen wurden im Fall der meisten Prop&#8209;2&#8209;enamide bei Dr&uuml;cken von 500&nbsp;bar, 1&nbsp;000&nbsp;bar und 1&nbsp;500&nbsp;bar durchgef&uuml;hrt. Die dadurch erhaltenen Aktivierungsvolumina k&ouml;nnen zur Absch&auml;tzung des Terminierungsgeschwindigkeitskoeffizienten bei Umgebungsdruck verwendet werden. Die Aktivierungsvolumina der Terminierungsgeschwindigkeitskoeffizienten von <i>N</i>,2&#8209;Dimethylprop&#8209;2&#8209;enamid und von Prop&#8209;2&#8209;enamid belaufen sich auf 12.4&nbsp;cm<sup>3</sup>&middot;mol<sup>&minus;1</sup> beziehungsweise 14.3&nbsp;cm<sup>3</sup>&middot;mol<sup>&minus;1</sup>. Das Aktivierungsvolumen im Fall von <i>N</i>,<i>N</i>&#8209;Dimethylprop&#8209;2&#8209;enamid (4.9&nbsp;cm<sup>3</sup>&middot;mol<sup>&minus;1</sup>) ist kleiner als erwartet. Terminierungsgeschwindigkeitskoeffizienten von 1&#8209;Vinylpyrrolidin&#8209;2&#8209;on konnten f&uuml;r einen gro&szlig;en Bereich der Anfangsmonomerkonzentration und des Grades des Monomerumsatzes erhalten werden. Diese Daten erm&ouml;glichen eine detaillierte Analyse der Parameter, die zur Beschreibung der Monomerumsatzabh&auml;ngigkeit des Terminierungsgeschwindigkeitskoeffizienten verwendet werden. Es wird angenommen, dass der Terminierungsgeschwindigkeitskoeffizient innerhalb des untersuchten Monomerumsatzbereichs durch Segment-, Translations- und Reaktionsdiffusion kontrolliert ist.<br> Im Fall von <i>N</i>,<i>N</i>&#8209;Dimethylprop&#8209;2&#8209;enamid und 1&#8209;Vinylpyrrolidin&#8209;2&#8209;on wurden dynamische Viskosit&auml;ten von Monomer&ndash;Wasser-Gemischen bei Umgebungsdruck bestimmt, um das Verst&auml;ndnis der Terminierungskinetik zu erleichtern. F&uuml;r diese beiden Monomere wurde durch Pulslaser-induzierte Polymerisation eine gro&szlig;e Anzahl von Terminierungsgeschwindigkeitskoeffizienten in Abh&auml;ngigkeit von der Anfangsmonomerkonzentration erhalten.<br> Zur Bestimmung des Terminierungsgeschwindigkeitskoeffizienten von Prop&#8209;2&#8209;enamid in Abh&auml;ngigkeit vom Monomerumsatz wurden chemisch initiierte Polymerisationen bei Umgebungsdruck durchgef&uuml;hrt. Die erhaltenen Werte stimmen gut mit Daten &uuml;berein, die mit Hilfe von Pulslaser-induzierten Polymerisationen ermittelt wurden.<br> Untersuchungen der bin&auml;ren Copolymerisation von 1&#8209;Vinylpyrrolidin&#8209;2&#8209;on und Natriumacrylat zeigten einen ausgepr&auml;gten Einbau von Natriumacrylat in das gebildete Copolymer. Dies wurde mittels Kernspinresonanzspektroskopie gemessen. Die Monomerreaktivit&auml;tsverh&auml;ltnisse wurden mit Hilfe der Lewis&ndash;Mayo-Gleichung bestimmt.

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