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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.
51

The influence of Nature and Nurture on speaker-specific parameters in twins speech / acoustics, articulation and perception

Weirich, Melanie 24 January 2012 (has links)
Die Dissertation thematisiert sprecherspezifische Variabilität bei ein- und zweieiigen Zwillingen hinsichtlich Artikulation, Akustik und Perzeption. Die zentrale Fragestellung ist, ob sprecherspezifische Charakteristika auf physiologisch-biologischen Differenzen der Sprecher beruhen (BIOLOGIE), oder sich auf gelernte, umweltabhängige Unterschiede zurückführen lassen (UMWELT). Artikulatorische und akustische Daten wurden von 4 eineiigen Zwillingspaaren (EZ, 100% genetische Übereinstimmung) und 3 zweieiigen Zwillingspaaren (ZZ, 50% genetische Übereinstimmung) analysiert. Zusätzlich wurde ein Perzeptionstest zur auditiven Ähnlichkeit der Zwillinge durchgeführt. Auf einen großen Einfluss des Faktors BIOLOGIE lässt sich schließen, wenn sich EZ ähnlicher sind als ZZ. Sind sich aber ZZ genauso ähnlich wie EZ, zeigt sich die Wichtigkeit der gleichen Lernumgebung (UMWELT). Die Ergebnisse weisen auf einen großen Einfluss des Faktors UMWELT und stützen die Hypothese, dass sprachliche Ziele gelernt sind und sich am auditiven Feedback orientieren. Darüber hinaus wurden drei Faktoren gefunden, die den Einfluss der BIOLOGIE intensivieren: a) Lautklasse, b) Wortakzent und c) Koartikulation. Plosive und Sibilanten sind aufgrund des stärker ausgeprägten linguo-palatalen Kontaktes mehr durch die individuelle Physiologie beeinflusst als Vokale. Außerdem wurde ein größerer Effekt des Faktors BIOLOGIE in unbetonten als in betonten Silben gefunden. Zusätzlich stellten sich koartikulatorische Prozesse als wichtig heraus: dynamische Parameter – artikulatorische Gesten und akustische Transitionen – sind stärker durch die Physiologie beeinflusst als statische Parameter – artikulatorische Ziele und stabile akustische Regionen. Sowohl der Faktor BIOLOGIE als auch der Faktor UMWELT sind einflussreiche Größen hinsichtlich sprecherspezifischer Variabilität. Welcher der beiden Faktoren die übergeordnete Rolle übernimmt, hängt von den spezifischen Charakteristika des untersuchten Parameters ab. / This dissertation examines inter-speaker variability in monozygotic (MZ) and dizygotic (DZ) twin pairs in regard to articulation, acoustics and perception. The aim of the study is to evaluate whether speaker-specific variability reflects physiological differences between speakers (NATURE) or bases on learned variation due to social environmental influences (NURTURE). Articulatory and acoustic data was analyzed from 4 MZ twin pairs (100% identical genes) and 3 DZ twin pairs (50 % identical genes). Additionally, a perception experiment was carried out to explore the perceived auditory similarity. The effect of NATURE should have a larger impact than the effect of NURTURE, if a parameter differs more in DZ than in MZ twin pairs. If MZ and DZ twins show the same amount of inter-speaker variability, NURTURE seems to be crucial. Results point to the importance of NURTURE and shared social environment. Nevertheless, three factors were found that intensify the effect of NATURE: a) phoneme class, b) lexical stress, and c) degree of coarticulation. Somatosensory feedback plays a larger role for consonants than for vowels, and thus individual physiology was found to shape articulation more in sibilants and stops than in vowels. Additionally, a stronger impact of NATURE was found in parameters that are auditorily less salient: unstressed syllables were more similar in MZ than in DZ twins, while for stressed syllables this was not the case. Moreover, coarticulation turned out to be essential: dynamic parameters – articulatory gestures and acoustic transitions – were more influenced by physiological constraints (NATURE) than static parameters – articulatory targets and stable acoustic regions. Thus, both NATURE and NURTURE are crucial influencing factors in speaker-specific variability. However, the relative importance of the two factors is highly dependent on the specific characteristics of the investigated parameter.
52

Functional competency of lower limb musculature in the elderly

Singh, Navrag B 01 July 2013 (has links)
Körperlich aktiv zu sein ist Grundlage unseres täglichen Lebens. Für alle diese Aktivitäten ist das kontinuierliche Zusammenspiel des senso-motorischen System (SMS) erforderlich. Die Kontrolle der verschiedenen afferenten und efferenten Subsysteme innerhalb des SMS basiert auf Feedback-Mechanismen, die die Aufrechterhaltung des Gleichgewichts und der Stabilität während den verschiedensten statischen als auch dynamischen Aktivitäten ermöglichen. Trotz dieser Kontroll- und Stabilisierungssystems ist das kinematische und kinetische Resultat nicht konstant; stattdessen ist bei globalen „Ganzkörper-Bewegungen“, und lokaler Muskelanspannung ständig eine gewisse Variabilität vorhanden. Die Interpretation dieser Variabilität bei Bewegungshandlungen ist kontrovers. Wobei große Variabilität ist nicht zwangsläufig ein Indikator für Defizite des SMS darstellt. Das Ziel dieser Dissertation war, die Variabilität bei lokalen und globalen Bewegungshandlungen in statischen und dynamischen Ausgangstellungen zu quantifizieren. Darüberhinaus, wurde der Zusammenhang zwischen lokaler Variabilität der Muskelkraftproduktion und der Variabilität bei globalen Bewegungshandlungen. Die Ergebnisse zeigen, dass lokale und globale Variabilität von Bewegungshandlungen in Menge und Muster verändert sind, nach Störung des SMS durch: Ermüdung, Veränderungen der Umfeldbedingungen, Alterung und bei Personen mit Sturzerfahrung. Außerdem wurde gezeigt, dass sowohl zu große als auch zu kleine Variabilität, ein entscheidendes funktionelles Defizit bei älteren Personen darstellt. Dieser Dissertation hebt die Bedeutung der Variabilität während wiederholter Bewegungshandlungen hervor, welche einen funktionellen Biomarker für die Beurteilung von Bewegungsstörungen darstellt. In der klinische Praxis könnte dieser helfen bei der frühen Identifikation von Personen mit Bewegungsstörungen, zur Entwicklung von individual-spezifischen Rehabilitationsmaßnahmen, sowie der Beurteilung verschiedener Therapieansätze. / Undertaking activities is fundamental throughout daily living. In order to successfully perform these activities, continuous involvement of the human sensori-motor system (HSMS) is required. The HSMS involves feedback mechanisms to control numerous afferent and the efferent subsystems to ensure maintenance of balance and stability during both static and dynamic activities. Despite such control and stabilizing mechanisms, the kinematic and kinetic output of a task is not constant; instead variability occurs during continuous performance of both global tasks such as standing and walking, as well as local force production. The interpretation of variability during output task performance remains controversial, with larger levels of variability not always indicating deficits in human-motor performance. The aim of this dissertation was to assess variability during local as well as global task performance in static and dynamic settings. Furthermore, the association between the level of variability during local force production and variability during global tasks such as standing and walking was also investigated. The results within this dissertation showed that variability during task performance is modified in magnitude as well as in structure after perturbation due to fatigue, changes in environmental conditions, and aging, as well as in fall-prone elderly individuals. Furthermore, both high as well as low levels of variation constitute a key functional deficit among elderly individuals. This dissertation highlights the importance of considering trial-to-trial variations during continuous task performance as a key functional biomarker for motor-related pathologies. Effective assessment of such measures of variability in clinical settings could effectively complement current clinical practice for both early and effective identification of individuals with motor-related pathology, designing subject-specific rehabilitation programs, and evaluating therapy efficacy.
53

Erdflechten und ihre Gesellschaften in Nordhessen mit besonderer Berücksichtigung der morphologischen und genetischen Variabilität bei Cladonia furcata (Hudson) Schrader / Terricolous lichens and their communities in North Hessen (Germany) with special emphasis on the morphological and genetical variability of Cladonia furcata (Hudson) Schrader

Günzl, Bettina 22 January 2004 (has links)
No description available.
54

Gli italiani a Dresda

Baggio, Serenella 02 July 2020 (has links)
La SLUB di Dresda riflette nella sua collezione italiana di manoscritti e antiche stampe non solo l’eclettismo dei gusti dei bibliofili sassoni o le diverse fortune dei loro agenti in Italia, ma la varietà dell’offerta culturale italiana, riflessa in modelli linguistici diversi per ragioni geografiche, sociali o anche solo diafasiche. Il giovane Cristiano I fu educato all’italiano probabilmente su due grammatiche in contrasto fra loro per motivi ideologici, una italianista, l’altra toscanista, come mostra il confronto delle loro marche d’uso. Allo straniero italofilo era richiesta una paziente tolleranza della variabilità, alimentata da accese questioni della lingua e da un polimorfismo ineliminabile in un paese da sempre poli-centrico e conflittuale.
55

Onkogenomische Aspekte Zytokin-assoziierter Signaltransduktion / Oncogenomic aspects of cytokine-associated signal transduction

Schoof, Nils 21 October 2008 (has links)
No description available.
56

Genetische Vielfalt und Vernetzung verschiedener Teilpopulationen von Corylus avellana L. und Prunus spinosa L. an Wald- und Wegrändern des Sollings / Genetic variation and fragmentation of different subpopulations of Corylus avellana L. and Prunus spinosa L. at the edge of the solling forest

Schmitt, Stephanie 06 November 2003 (has links)
No description available.
57

Language Family Engineering with Features and Role-Based Composition

Wende, Christian 19 June 2012 (has links) (PDF)
The benefits of Model-Driven Software Development (MDSD) and Domain-Specific Languages (DSLs) wrt. efficiency and quality in software engineering increase the demand for custom languages and the need for efficient methods for language engineering. This motivated the introduction of language families that aim at further reducing the development costs and the maintenance effort for custom languages. The basic idea is to exploit the commonalities and provide means to enable systematic variation among a set of related languages. Current techniques and methodologies for language engineering are not prepared to deal with the particular challenges of language families. First, language engineering processes lack means for a systematic analysis, specification and management of variability as found in language families. Second, technical approaches for a modular specification and realisation of languages suffer from insufficient modularity properties. They lack means for information hiding, for explicit module interfaces, for loose coupling, and for flexible module integration. Our first contribution, Feature-Oriented Language Family Engineering (LFE), adapts methods from Software Product Line Engineering to the domain of language engineering. It extends Feature-Oriented Software Development to support metamodelling approaches used for language engineering and replaces state-of-the-art processes by a variability- and reuse-oriented LFE process. Feature-oriented techniques are used as means for systematic variability analysis, variability management, language variant specification, and the automatic derivation of custom language variants. Our second contribution, Integrative Role-Based Language Composition, extends existing metamodelling approaches with roles. Role models introduce enhanced modularity for object-oriented specifications like abstract syntax metamodels. We introduce a role-based language for the specification of language components, a role-based composition language, and an extensible composition system to evaluate role-based language composition programs. The composition system introduces integrative, grey-box composition techniques for language syntax and semantics that realise the statics and dynamics of role composition, respectively. To evaluate the introduced approaches and to show their applicability, we apply them in three major case studies. First, we use feature-oriented LFE to implement a language family for the ontology language OWL. Second, we employ role-based language composition to realise a component-based version of the language OCL. Third, we apply both approaches in combination for the development of SumUp, a family of languages for mathematical equations.
58

Language Family Engineering with Features and Role-Based Composition

Wende, Christian 16 March 2012 (has links)
The benefits of Model-Driven Software Development (MDSD) and Domain-Specific Languages (DSLs) wrt. efficiency and quality in software engineering increase the demand for custom languages and the need for efficient methods for language engineering. This motivated the introduction of language families that aim at further reducing the development costs and the maintenance effort for custom languages. The basic idea is to exploit the commonalities and provide means to enable systematic variation among a set of related languages. Current techniques and methodologies for language engineering are not prepared to deal with the particular challenges of language families. First, language engineering processes lack means for a systematic analysis, specification and management of variability as found in language families. Second, technical approaches for a modular specification and realisation of languages suffer from insufficient modularity properties. They lack means for information hiding, for explicit module interfaces, for loose coupling, and for flexible module integration. Our first contribution, Feature-Oriented Language Family Engineering (LFE), adapts methods from Software Product Line Engineering to the domain of language engineering. It extends Feature-Oriented Software Development to support metamodelling approaches used for language engineering and replaces state-of-the-art processes by a variability- and reuse-oriented LFE process. Feature-oriented techniques are used as means for systematic variability analysis, variability management, language variant specification, and the automatic derivation of custom language variants. Our second contribution, Integrative Role-Based Language Composition, extends existing metamodelling approaches with roles. Role models introduce enhanced modularity for object-oriented specifications like abstract syntax metamodels. We introduce a role-based language for the specification of language components, a role-based composition language, and an extensible composition system to evaluate role-based language composition programs. The composition system introduces integrative, grey-box composition techniques for language syntax and semantics that realise the statics and dynamics of role composition, respectively. To evaluate the introduced approaches and to show their applicability, we apply them in three major case studies. First, we use feature-oriented LFE to implement a language family for the ontology language OWL. Second, we employ role-based language composition to realise a component-based version of the language OCL. Third, we apply both approaches in combination for the development of SumUp, a family of languages for mathematical equations.:1. Introduction 1.1. The Omnipresence of Language Families 1.2. Challenges for Language Family Engineering 1.3. Language Family Engineering with Features and Role-Based Composition 2. Review of Current Language Engineering 2.1. Language Engineering Processes 2.1.1. Analysis Phase 2.1.2. Design Phase 2.1.3. Implementation Phase 2.1.4. Applicability in Language Family Engineering 2.1.5. Requirements for an Enhanced LFE Process 2.2. Technical Approaches in Language Engineering 2.2.1. Specification of Abstract Syntax 2.2.2. Specification of Concrete Syntax 2.2.3. Specification of Semantics 2.2.4. Requirements for an Enhanced LFE Technique 3. Feature-Oriented Language Family Engineering 3.1. Foundations of Feature-Oriented SPLE 3.1.1. Introduction to SPLE 3.1.2. Feature-Oriented Software Development 3.2. Feature-Oriented Language Family Engineering 3.2.1. Variability and Variant Specification in LFE 3.2.2. Product-Line Realisation, Mapping and Variant Derivation for LFE 3.3. Case Study: Scalability in Ontology Specification, Evaluation and Application 3.3.1. Review of Evolution, Customisation and Combination in the OWL LanguageFamily 3.3.2. Application of Feature-Oriented Language Family Engineering for OWL 3.4. Discussion 3.4.1. Contributions 3.4.2. Related Work. 3.4.3. Conclusion 4. Integrative, Role-Based Composition for Language Family Engineering 4.1. Foundations of Role-Based Modelling. 4.1.1. Information Hiding and Interface Specification in Role Models 4.1.2. Loose Coupling and Flexible Integration in Role Composition 4.2. The LanGems Language Composition System 4.2.1. The Language Component Specification Language . 4.2.2. TheLanguageCompositionLanguage 4.2.3. TechniquesofLanguageComposition 4.3. Case Study: Component-based OCL 4.3.1. Role-Based OCL Modularisation 4.3.2. Role-Based OCL Composition 4.4. Discussion 4.4.1. Contributions 4.4.2. Related Work 4.4.3. Conclusion 5. LFE with Integrative, Role-Based Syntax and Semantics Composition 5.1. Integrating Features and Roles 5.2. SumUp Case Study 5.2.1. Motivation 5.2.2. Feature-Oriented Variability and Variant Specification 5.2.3. Role-Based Component Realisation 5.2.4. Feature-Oriented Variability and Variant Evolution 5.2.5. Model-driven Concrete Syntax Realisation 5.2.6. Model-driven Semantics Realisation 5.2.7. Role-Based Composition and Feature Mapping 5.2.8. Language Variant Derivation 5.3. Conclusion 6. Conclusion 6.1. Contributions 6.2. Outlook 6.2.1. Co-Evolution in Language Families 6.2.2. Role-Based Tool Integration. 6.2.3. Automatic Modularisation of Existing Language Families 6.2.4. Language Component Library Appendix A Appendix B Bibliography
59

Fertigungssteuerung in der Musterfertigung von Systemlieferanten

Kienzle, Florian 09 January 2012 (has links)
An die Musterfertigung von Systemlieferanten stellt sich die besondere Anforderung, Prototypen verschiedener Erzeugnisse, in vielfältigen Kundenvarianten, in jeweils unterschiedlichen Produktreifegraden, parallel zu fertigen. Daraus resultiert eine spezifische Variabilitätsausprägung der Produktionsplanungsparameter, die zu einer hohen Komplexität und Turbulenz in der Ablaufsteuerung einer Musterfertigung führt. Infolgedessen gilt der Planparametervariabilitätsfall Musterfertigung, sowohl in der Theorie als auch in der betrieblichen Praxis, als ein bislang ungelöstes Steuerungsproblem, welches ein hohes Verbesserungspotenzial aufweist. Die vorliegende Arbeit analysiert und beleuchtet diesen Problemfall im Rahmen einer vergleichenden Fallstudienuntersuchung. Aufbauend auf den gewonnenen Erkenntnissen wird ein Konzept zur Steuerung einer Musterfertigung bei Systemlieferanten entwickelt und in seinem Anwendungszusammenhang evaluiert. / Sample production of tier 1 automotive suppliers demands producing simultaneously different product samples in many customised versions and within various maturity levels. The associated variability of the time-phased work content leads to a high degree of complexity and turbulence in the manufacturing process of such a production type. Therefore, sample production control becomes significantly more complicated and most existing control approaches fail in the real world. For this reason the present thesis examines this subject matter by means of a comparative case study. Based on the findings a customized production control concept will be introduced that fully adapts the specific needs of sample production of tier 1 automotive suppliers.
60

Untersuchungen zur Variabilität der Ausbildung hyperdermaler Wasserspeichergewebe unter Berücksichtigung variegater Periklinalchimären

Faßmann, Natalie 09 June 2008 (has links)
Die Arbeit ist in drei Teile untergliedert: Die Struktur "Hypodermales Wasserspeichergewebe" wird unter anatomischen, ökomorphologischen und evolutionsbiologischen Gesichtspunkten betrachtet. Die Anwesenheit eines farblosen Hypoderms erschwert bei der Musteranalyse variegater Periklinalchimären die Bestimmung der Konstitution der L2. Variegate Periklinalchimären mit Hypodermbildung wurden auf die Möglichkeiten der Bestimmung der L2 hin untersucht. Es werden verschiedene Entstehungsformen von maskierenden Mustern und die noch nicht beschriebenen Ringzellen vorgestellt, die den Idiotyp der L2-bürtigen Schicht anzeigen können. Ringzellen sind die Zellen, die im Bereich der Schließzellen an den substomatären Interzellularraum grenzen. Sie bilden dabei einen Ring um die Schließzellen, der im Flächenschnitt zu erkennen ist. Hypodermale Wasserspeichergewebe sind hauptsächlich bei tropischen Arten verbreitet. Die xeromorphe Struktur kommt sowohl bei den epiphytischen Bromelien als auch bei den hygromorphen Schattenpflanzen des tropischen Regenwaldes vor. Die beiden Selektionsfaktoren Trockenheit und Lichtintensität werden als mögliche Einflussfaktoren auf die Hypodermbildung diskutiert. Beispiele dafür, dass der Faktor Licht auch einen modifikativen Einfluss auf die Differenzierung der Hypodermzellen zu haben scheint, werden vorgestellt. Die Struktur "Hypodermales Wasserspeichergewebe" ist sowohl bei Monokotylen als auch Dikotylen gleichermaßen verbreitet. Es wird daher vermutet, dass es sich um eine analoge Struktur handelt, die mehrmals voneinander unabhängig zu verschiedenen Zeiten bei verschiedenen Arten entstanden ist. Innerhalb einer Gruppe verwandter Arten konnte sie mithilfe der Homologiekriterien als homolog eingestuft werden. / This paper contains three different issues: The structure "hypodermal water storage tissue" is considered from the anatomical, the ecomorphological and evolutionary aspect. Because hypodermal layers are non-green, it is difficult to make a pattern analysis of variegated periclinal chimeras and to determine the constitution of L2. Variegated periclinal chimeras with hypodermal layers were examined to the possibilities of determining L2. Different origins of masking patterns and the non-yet described ring cells are presented. Both structures are able to show the L2-genotype. Ring cells are those cells bordering the intercellular space near the stomata. In a cut parallel to the surface the ring built by ring cells is seen. The hypodermal water storage tissue is mainly distributed among tropical species. The xeromorphic structure occurs both to the epiphytic bromeliads and to the hygromorphic shadow plants of the tropical rainforest. The environmental factors humidity and solar radiation are discussed as possible influences on the development of hypodermal layers. Examples for the apparent modifying influence of solar radiation on the development of hypodermal cells are presented. The structure "hypodermal water storage tissue" occurs both to monocots and dicots. That indicates that it is an analogues structure and that it evolved several times independent of each other in different species. Among a group of nearly related species it could be classified by the aid of the criteria of homology as a homologues structure.

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