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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.
21

Les microalgues : nouvelles sources de molécules élicitrices pour la santé et la defense des plantes. / Phaeodactylum tricornutum : new source of eliciting molecules for plant defense and health

Chuberre, Coralie 04 October 2019 (has links)
La protection intégrée, qui vise à réduire l’usage des pesticides, est un défi majeur pour l’agriculture du XXIème siècle. Le développement de nouvelles approches agronomiques qui concilient environnement et agriculture est une condition indispensable pour l’agriculture de demain. Dans ce contexte, l’utilisation d’éliciteurs capables de mimer une attaque pathogène et de promouvoir un état de résistance chez les plantes face à des maladies représente une alternative naturelle à la lutte chimique. Ces éliciteurs sont nommés les stimulateurs de défense des plantes (SDP). Ils peuvent provenir de différentes sources et être extraits à partir de macroalgues comme c’est le cas des SDP à base de polysaccharides d’algues tels que la laminarine utilisée pour stimuler l’immunité de plantes agronomiques. Toutefois, l’exploitation de ces ressources dans leur milieu naturel et les difficultés de production liées à leur cycle de développement constituent des freins à leur utilisation. La valorisation des microalgues comme source de SDP pourrait permettre de s’affranchir de ces contraintes. Cependant la recherche et de molécules SDP chez les microalgues est encore peu abordée. Au cours de ce travail, le potentiel d’une culture de microalgue, Phaeodactylum tricornutum, à induire des réactions de défense chez les plantes a été évalué. Un broyat cellulaire a été appliqué sur des plantules d’Arabidopsis thaliana. Le caractère éliciteur de ce broyat a été testé et caractérisé par des approches microscopiques, physiologiques et moléculaires. Les résultats ont montré que les plantes traitées présentaient des niveaux d’expression des gènes PR-1, PAD3, ACS6 et WRKY40 et un niveau de protection contre la bactérie Pseudomonas syringae DC3000 (Pst) plus élevés que les plantes non traitées. De plus, un effet bactéricide in vitro sur la bactérie Pst a été observé. Ces résultats offrent de nouvelles perspectives pour le développement de produits SDP d’origine naturelle capables de protéger les cultures. / Integrated plant protection, which aims to reduce the use of pesticide, is a major challenge for the agriculture of the 21st century. The development and application of new agronomic approaches is a prerequisite for crop protection in a sustainable agriculture system. In this context, the use of elicitors capable of mimicking a pathogenic attack and promoting a plant resistance state against diseases is a natural alternative to the use of agro-chemicals. These elicitors are also called plant defense stimulators (PDS). These can be obtained from different sources including macroalgae as it the case for the polysaccharide-based PDS laminarin that is currently used for the protection of a number of crops. However, the exploitation of these natural resources and the difficulties of their production due to their development cycle do hamper their use at a large scale. One of the possibilities to overcome these difficulties is the use of microalgae as a source of PDS. But this possibility and the potential of microalgaederived PDS for crop protection are currently under investigated. In the present work, we have used a cell extract from the microalgae Phaeodactylum tricornutum and assessed its defense response-eliciting activities on Arabidopsis thaliana seedlings by using microscopic, physiological and molecular approaches. The results show that treated plants exhibit higher levels of expression of the PR-1, PAD3, ACS6 and WRKY40 genes and a higher level of protection against the pathogenic bacterium Pseudomonas syringae DC3000 (Pst) than nontreated plants. An In vitro antibacterial activity on the Pst bacteria was also observed. Our findings suggest that P. tricornutum cell extracts are able to activate plant immune responses and offer new perspectives for the development of novel plant defense stimulators.
22

Multivariate Korrektur des Temperatureinflusses in der NIR-spektroskopischen Materialfeuchtebestimmung / Multivariate Correction of Temperature Influence in the NIR-spectrocopic Moisture Analysis

Groß, Sven 29 April 2009 (has links)
No description available.
23

Study of Organic Semiconductors for Device Applications

Stella, Marco 12 March 2010 (has links)
Organic semiconductors are being investigated as an alternative to more traditional materials such as silicon, for the fabrication of different types of electronic devices. The advantages of such materials are flexibility, lightness and quick and low cost device production methods. In this thesis we analyze some small molecule organic semiconductors for their use in devices such as thin film transistors and photovoltaic cells. These materials, deposited in thin films on glass by thermal vacuum evaporation, are copper phthalocyanine (CuPc) and pentacene, p-type materials, fullerene (C60), PTCDA and PTCDI-C13, that are n-type. We analyze their optical properties by optical transmittance measurement and photothermal deflection spectroscopy (PDS). By such means we obtain the absorption coefficient of the materials in sub-gap region (near infrared - NIR), directly related with the density of electronic states. Furthermore, we examine thin film microstructure by X-ray diffraction (XRD) in order to observe if it is amorphous or polycrystalline. The data obtained by optical methods are used to calculate optical gap (Eg) and Urbach energy (Eu). The former of these parameters gives important information about the absorption properties of the material in the visible and NIR ranges of the spectrum, while the latter about the structural disorder in the film. Since a clear model for organic semiconductors is still not defined, in both cases we employ models that are usually considered in the case of inorganic semiconductors. The XRD analysis indicates that, in the deposition conditions used in this work, only C60 grows with amorphous structure while all the other materials are polycrystalline. Such result is used to determine which law can be used to estimate the optical gap: the general law for direct allowed electronic transitions in semiconductors for polycrystalline materials or the Tauc law for amorphous ones. The Urbach law, usually employed to have an idea about the amount of disorder in amorphous films, is used for all our materials as an indicator of thin film quality. Furthermore, we examine the stability of the materials over time under exposure to direct radiation and atmosphere and to compare the results with the ones obtained for samples simply exposed to atmosphere. PTCDA and CuPc have demonstrated to be stable against oxidizing agents that are present in atmosphere while the other materials suffer modifications in their optical properties. Such variations, principally located in the sub-gap region of the absorption region, indicate that an increase in the absorption level is obtained, probably due to the presence of defects that could work as charge carrier traps. Annealing treatments are performed on the degraded materials to observe that the degradation process is not reversible. Organic photovoltaic cells always include a heterojunction between two semiconductors, so the same study is performed on mixtures of two materials, a p-type and an n-type one, testing all the possible combinations between the investigated materials. The films are obtained by co-evaporating the two materials in 1:1 proportion. A mixture containing a degrading material also degrades. Heat treatments performed on the samples yield a partial crystallization of some materials but not of others and fail to recover the original optical properties when degradation occurs. Finally, two types of devices are fabricated: thin film transistors (TFTs) using PTCDI-C13 and diodes with CuPc. In the first case we obtain very interesting results, determining that the devices work as typical n-type channel transistors. An analysis of the device characterizations allows us to determine the density of electronic states in the channel obtaining a result that is very similar to the one obtained by optical means on the same material. In the second case we observe the typical diode behaviour but the response with light of such devices, characterized by having a structure similar to the one of Schottky type solar cells, is very low. / Los semiconductores orgánicos están siendo investigados como alternativos a materiales más tradicionales, como el silicio, para la fabricación de varios tipos de dispositivos electrónicos. Las ventajas que presentan tales materiales son flexibilidad, ligereza, rapidez y bajo coste de los métodos de producción de los dispositivos orgánicos. En esta tesis se analizan algunos semiconductores orgánicos de molécula pequeña para su aplicación en dispositivos como los transistores en capa delgada y las células fotovoltaicas. Tales materiales, depositados en capa delgada por evaporación térmica en vacío, son ftalocianina de cobre (CuPc) y pentaceno, de tipo p, fullereno (C60), PTCDA y PTCDI-C13, de tipo n. Se analizan las propiedades ópticas de ellos por medio de la medida de Trasmitancia Óptica y de la Espectroscopia de Deflección Fototérmica (PDS). Además se analiza la microestructura de las capas delgadas por difracción de rayos X (XRD) con el objetivo de observar si las capas tienen estructura amorfa o policristalina. Los datos son utilizados para calcular el gap óptico (Eg) y la energía de Urbach (Eu). Se analiza la estabilidad de los materiales con el pasar del tiempo y la exposición a irradiación directa, por un lado, y a la atmosfera, por otro lado. El fullereno es el único material que se deposita con estructura amorfa. Además se ha observado que CuPc y PTCDA son estables frente a la degradación por exposición a agentes oxidantes. Las células fotovoltaicas orgánicas incluyen siempre una heterounión entre dos semiconductores, así que se repite el mismo estudio sobre mezclas de dos materiales, uno de tipo p y otro de tipo n, probando todas las combinaciones posibles con los materiales analizados. Se observa que en una mezcla que incluya un material que presenta inestabilidad también hay degradación. Los tratamientos térmicos efectuados sobre las muestras han permiten obtener una parcial cristalización de algunos materiales pero no de otros y no llevan a recuperar las propiedades ópticas originarias, perdidas con la degradación. Finalmente, se fabrican dos tipos de dispositivos: TFTs de PTCDI-C13 y diodos de CuPc. En el primer caso se obtienen resultados interesantes, detectando que los dispositivos funcionan como típicos transistores en capa delgada de tipo n. En el segundo caso se observa el típico comportamiento de los diodos. Sin embargo, la respuesta con luz de tales dispositivos, de estructura análoga a fotocélulas de tipo Schottky, es muy escasa.
24

Théorie et applications des systèmes polyphasiques dispersés aux cultures cellulaires en chémostat / Theory and applications of polyphasic dispersed systems to chemostat cellular cultures

Thierie, Jacques 05 September 2005 (has links)
Les systèmes microbiologiques naturels (colonne d’eau), semi-naturels (station d’épuration), mais surtout industriels ou de laboratoire (bioréacteurs) sont communément représentés par des modèles mathématiques destinés à l’étude, à la compréhension des phénomènes ou au contrôle des processus (de production, par exemple).<p><p>Dans l’énorme majorité des cas, lorsque les cellules (procaryotes ou eucaryotes) mises en jeu dans ces systèmes sont en suspension, le formalisme de ces modèles non structurés traite le système comme s’il était homogène. Or, en toute rigueur, il est clair que cette approche n’est qu’une approximation et que nous avons à faire à des phénomènes hétérogènes, formés de plusieurs phases (solide, liquide, gazeuse) intimement mélangées. Nous désignons ces systèmes comme « polyphasiques dispersés » (SPD). Ce sont des systèmes thermodynami-quement instables, (presque) toujours ouverts.<p><p>La démarche que nous avons entreprise consiste à examiner si le fait de considérer des systèmes dits « homogènes » comme des systèmes hétérogènes (ce qu’ils sont en réalité) apporte, malgré une complication du traitement mathématique, un complément d’information significatif et pertinent. <p><p>La démarche s’est faite en deux temps :<p>·\ / Doctorat en sciences, Spécialisation biologie moléculaire / info:eu-repo/semantics/nonPublished
25

Diagnostika vysokonapěťových kondenzátorů pro kaskádní napěťový násobič / Diagnosis of high voltage capacitors for cascade voltage multiplier

Baev, Dmitriy January 2017 (has links)
The main subject of the final thesis is to find a suitable method for measuring the partial discharge (PD) in the dielectric of high-voltage capacitor. In the theoretical part of my thesis contains from the mechanisms of origin and the harmful effects of partial discharge at high voltage insulation of capacitor. It describes the global galvanic method of partial discharge measurement, the principle of cascade voltage multiplier, its main components are high-voltage capacitor and diode, facilities quality measurement of capacitors for voltage multipliers, advantages and disadvantages and principles of HIPOTRONICS DDX-8003 with the pulse discrimination system. In the experimental part of the diploma thesis is familiar with the diagnostics of high – voltage capacitors by means of laboratory measurements on the electronic bridge and with the help of partial discharge measurement system. Design of suitable electrode arrangement is described which eliminates the influence of corona which makes it impossible to measure partial discharges and the dissipation factor (tg ). Analysis data from measurement and determination of quality level, eventual degradation of measured capacitors. The result of this project should be designed the methodology for finding of poor – quality capacitors in order to increase the reliability of the voltage multiplier.
26

Analyses on tech-enhanced and anonymous Peer Discussion as well as anonymous Control Facilities for tech-enhanced Learning / Analysen zur technologieunterstützten und anonymem Peer Discussion sowie anonymen Einflusswerkzeuge für technologieunterstütztes Lernen

Hara, Tenshi 12 September 2016 (has links) (PDF)
An increasing number of university freshmen has been observable in absolute number as well as percentage of population over the last decade. However, at the same time the drop-out rate has increased significantly. While a drop in attendance could be observed at the same time, statistics show that young professionals consider only roughly thirty percent of their qualification to originate in their university education. Taking this into consideration with the before mentioned, one conclusion could be that students fail to see the importance of fundamental classes and choose to seek knowledge elsewhere, for example in free online courses. However, the so acquired knowledge is a non-attributable qualification. One solution to this problem must be to make on-site activities more attractive. A promising approach for raised attractiveness would be to support students in self-regulated learning processes, making them experience importance and value of own decisions based on realistic self-assessment and self-evaluation. At the same time, strict ex-cathedra teaching should be replaced by interactive forms of education, ideally activating on a meta-cognitive level. Particularly, as many students bring mobile communication devices into classes, this promising approach could be extended by utilising these mobile devices as second screens. That way, enhanced learning experiences can be provided. The basic idea is simple, namely to contribute to psychological concepts with the means of computer science. An example for this idea are audience response systems. There has been numerous research into these and related approaches for university readings, but other forms of education have not been sufficiently considered, for example tutorials. This technological aspect can be combined with recent didactics research and concepts like peer instruction or visible learning. Therefore, this dissertation presents an experimental approach at providing existing IT solutions for on-site tutorials, specifically tools for audience responses, evaluations, learning demand assessments, peer discussion, and virtual interactive whiteboards. These tools are provided under observation of anonymity and cognisant incidental utilisation. They provide insight into students\' motivation to attend classes, their motivation to utilise tools, and into their tool utilisation itself. Experimental findings are combined into an extensible system concept consisting of three major tool classes: anonymous peer discussion means, anonymous control facilities, and learning demand assessment. With the exception of the latter, promising findings in context of tutorials are presented, for example the reduction of audience response systems to an emergency brake, the versatility of (peer) discussion systems, or a demand for retroactive deanonymisation of contributions. The overall positive impact of tool utilisation on motivation to attend and perceived value of tutorials is discussed and supplemented by a positive impact on the final exams\' outcomes. / Über die vergangene Dekade ist eine zunehmende Zahl Studienanfänger beobachtbar, sowohl in der absoluten Anzahl, als auch im Bevölkerungsanteil. Demgegenüber steht aber eine überproportional hohe Steigerung der Abbruchquote. Während gleichzeitig die Anwesenheit in universitären Lehrveranstaltungen sinkt, zeigen Statistiken, dass nur etwa ein Drittel der Berufseinsteiger die Grundlagen ihrer Qualifikation im Studium sieht. Daraus könnte man ableiten, dass Studierende den Wert und die Bedeutung universitärer Ausbildung unterschätzen und stattdessen Wissen in anderen Quellen suchen, beispielsweise unentgeltlichen Online-Angeboten. Das auf diese Art angeeignete Wissen stellt aber eine formell nicht nachweise Qualifikation dar. Ein Weg aus diesem Dilemma muss die Steigerung der Attraktivität der universitären Lehrveranstaltungen sein. Ein vielversprechender Ansatz ist die Unterstützung der Studierenden im selbst-regulierten Lernen, wodurch sie die Wichtigkeit und den Wert eigener Entscheidung(sfindungsprozesse) auf Basis realistischer Selbsteinschätzung und Selbstevaluation erlernen. Gleichzeitig sollte Frontalunterricht durch interaktive Lehrformen ersetzt werden, idealerweise durch Aktivierung auf meta-kognitiver Ebene. Dies ist vielversprechend insbesondere, weil viele Studierende ihre eigenen mobilen Endgeräte in Lehrveranstaltungen bringen. Diese Geräte können als Second Screen für die neuen Lehrkonzepte verwendet werden. Auf diese Art kann dann eine verbesserte Lernerfahrung vermittelt werden. Die Grundidee ist simpel, nämlich in der Psychologie bewährte Didaktik-Konzepte durch die Mittel der Informatik zu unterstützen. Ein Beispiel dafür sind Audience Response Systeme, die hinlänglich im Rahmen von Vorlesungen untersucht worden sind. Andere Lehrformen wurden dabei jedoch unzureichend berücksichtigt, beispielsweise Tutorien. Ähnliche Überlegungen gelten natürlich auch für bewährte didaktische Konzepte wie Peer Instruction oder Betrachtungen in Form von Visible Learning. Deshalb präsentiert diese Dissertation einen experimentellen Ansatz, informationstechnische Lösungen für vor-Ort-Übungen anzubieten, nämlich Werkzeuge für Audience Response Systeme, Evaluationen, Lernbedarfsermittlung, Peer Discussion, sowie virtuelle interaktive Whiteboards. Die genannten Werkzeuge wurden unter Beachtung von Anonymitäts- und Beiläufigkeitsaspekten bereitgestellt. Sie erlauben einen Einblick in die Motivation der Studierenden Tutorien zu besuchen und die Werkzeuge zu nutzen, sowie ihr Nutzungsverhalten selbst. Die experimentellen Ergebnisse werden in ein erweiterbares Systemkonzept kombiniert, das drei Werkzeugklassen unterstützt: anonyme Peer Discussion, anonyme Kontrollwerkzeuge und Lernbedarfsermittlung. Für die ersten beiden Klassen liegen vielversprechende Ergebnisse vor, beispielsweise die notwendige Reduktion des Audience Response Systems auf eine Art Notbremse, die Vielseitigkeit von (Peer-)Discussion-Systemen, oder aber auch der Bedarf für eine retroaktive Deanonymisierung von initial anonymen Beiträgen. Der allgemein positive Einfluss der Werkzeugnutzung auf die Motivation an Tutorien teilzunehmen sowie den wahrgenommenen Wert der Tutorien werden abschließend diskutiert und durch verbesserte Abschlussklausurergebnisse untermauert.
27

Analyses on tech-enhanced and anonymous Peer Discussion as well as anonymous Control Facilities for tech-enhanced Learning

Hara, Tenshi 14 June 2016 (has links)
An increasing number of university freshmen has been observable in absolute number as well as percentage of population over the last decade. However, at the same time the drop-out rate has increased significantly. While a drop in attendance could be observed at the same time, statistics show that young professionals consider only roughly thirty percent of their qualification to originate in their university education. Taking this into consideration with the before mentioned, one conclusion could be that students fail to see the importance of fundamental classes and choose to seek knowledge elsewhere, for example in free online courses. However, the so acquired knowledge is a non-attributable qualification. One solution to this problem must be to make on-site activities more attractive. A promising approach for raised attractiveness would be to support students in self-regulated learning processes, making them experience importance and value of own decisions based on realistic self-assessment and self-evaluation. At the same time, strict ex-cathedra teaching should be replaced by interactive forms of education, ideally activating on a meta-cognitive level. Particularly, as many students bring mobile communication devices into classes, this promising approach could be extended by utilising these mobile devices as second screens. That way, enhanced learning experiences can be provided. The basic idea is simple, namely to contribute to psychological concepts with the means of computer science. An example for this idea are audience response systems. There has been numerous research into these and related approaches for university readings, but other forms of education have not been sufficiently considered, for example tutorials. This technological aspect can be combined with recent didactics research and concepts like peer instruction or visible learning. Therefore, this dissertation presents an experimental approach at providing existing IT solutions for on-site tutorials, specifically tools for audience responses, evaluations, learning demand assessments, peer discussion, and virtual interactive whiteboards. These tools are provided under observation of anonymity and cognisant incidental utilisation. They provide insight into students\' motivation to attend classes, their motivation to utilise tools, and into their tool utilisation itself. Experimental findings are combined into an extensible system concept consisting of three major tool classes: anonymous peer discussion means, anonymous control facilities, and learning demand assessment. With the exception of the latter, promising findings in context of tutorials are presented, for example the reduction of audience response systems to an emergency brake, the versatility of (peer) discussion systems, or a demand for retroactive deanonymisation of contributions. The overall positive impact of tool utilisation on motivation to attend and perceived value of tutorials is discussed and supplemented by a positive impact on the final exams\' outcomes.:List of Definitions, Theorems and Proofs List of Figures List of Tables Introduction and Motivation Part I: Propaedeutics 1 Working Theses 1.1 Definitions 1.2 Context of Working Theses and Definitions 2 Existing Concepts 2.1 Psychology 2.1.1 Self-Regulation and self-regulated Learning 2.1.2 Peer Instruction, Peer Discussion 2.1.3 Learning Process Supervision: Learning Demand Assessment 2.1.4 Cognitive Activation 2.1.5 Note on Gamification 2.1.6 Note on Blended Learning 2.2 Computer Science 2.2.1 Learning Platforms 2.2.2 Audience Response Systems (ARS) 2.2.3 Virtual Interactive Whiteboard Systems (V-IWB) 2.2.4 Cognisant Incidential Utilisation (CIU) 2.3 Appraisal 3 Related Work 3.1 Visible Learning 3.2 auditorium 3.3 Auditorium Mobile Classroom Service 3.4 ARSnova and other Audience Response Systems 3.5 Google Classroom 3.6 StackOverflow 3.7 AwwApp Part II: Proceedings 4 Global Picture and Prototype 4.1 Global Picture 4.2 System Architecture 4.2.1 Anonymous Discussion Means 4.2.2 Anonymous Control Facilities 4.3 Implementation 4.3.1 The Prototype 5 Investigated Tools 5.1 Note on Methodology 5.2 Anonymity 5.2.1 Methodology 5.2.2 Visible Learning Effects 5.2.3 Assertion 5.2.4 Experiments 5.2.5 Results 5.2.6 Conclusions 5.3 Learning Demand Assessment 5.3.1 Methodology 5.3.2 Visible Learning Effects 5.3.3 Tool Description 5.3.4 Assertion 5.3.5 Experiments 5.3.6 Results 5.3.7 Conclusions 5.4 Peer Discussion System 5.4.1 Methodology 5.4.2 Visible Learning Effects 5.4.3 Tool Description 5.4.4 Assertion 5.4.5 Experiments 5.4.6 Results 5.4.7 Conclusions 5.5 Virtual Interactive Whiteboard 5.5.1 Methodology 5.5.2 Visible Learning Effects 5.5.3 Tool Description 5.5.4 Assertion 5.5.5 Experiments 5.5.6 Results 5.5.7 Conclusions 5.6 Audience Response System and Emergency Brake 5.6.1 Methodology 5.6.2 Visible Learning Effects 5.6.3 Tool Description 5.6.4 Assertion 5.6.5 Experiments 5.6.6 Results 5.6.7 Conclusions 5.7 Evaluation System 5.7.1 Methodology 5.7.2 Visible Learning Effects 5.7.3 Tool Description 5.7.4 Assertion 5.7.5 Experiments 5.7.6 Results and Conclusion 6 Exam Outcome 7 Utilisation and Motivation 7.1 Prototype Utilisation 7.2 Motivational Aspects Part III: Appraisal 8 Lessons learned 9 Discussion 9.1 Working Theses’ Validity 9.2 Research Community: Impact and Outlook 9.2.1 Significance to Learning Psychology 9.3 Possible Extension of existing Solutions 10 Conclusion 10.1 Summary of scientific Contributions 10.2 Future Work Part IV: Appendix A Experimental Arrangement B Questionnaires B.1 Platform Feedback Sheet B.1.1 Original PFS in 2014 B.1.2 Original PFS in 2015 B.2 Minute Paper B.3 Motivation and Utilisation Questionnaires B.3.1 Motivation 2013 and 2014 B.3.2 Motivation 2015 B.3.3 Utilisation 2014 B.3.4 Utilisation 2015, Rev. I B.3.5 Utilisation 2015, Rev. II C References C.1 Auxiliary Means D Publications D.1 Original Research Contributions D.2 Student Theses E Glossary F Index G Milestones Acknowledgements / Über die vergangene Dekade ist eine zunehmende Zahl Studienanfänger beobachtbar, sowohl in der absoluten Anzahl, als auch im Bevölkerungsanteil. Demgegenüber steht aber eine überproportional hohe Steigerung der Abbruchquote. Während gleichzeitig die Anwesenheit in universitären Lehrveranstaltungen sinkt, zeigen Statistiken, dass nur etwa ein Drittel der Berufseinsteiger die Grundlagen ihrer Qualifikation im Studium sieht. Daraus könnte man ableiten, dass Studierende den Wert und die Bedeutung universitärer Ausbildung unterschätzen und stattdessen Wissen in anderen Quellen suchen, beispielsweise unentgeltlichen Online-Angeboten. Das auf diese Art angeeignete Wissen stellt aber eine formell nicht nachweise Qualifikation dar. Ein Weg aus diesem Dilemma muss die Steigerung der Attraktivität der universitären Lehrveranstaltungen sein. Ein vielversprechender Ansatz ist die Unterstützung der Studierenden im selbst-regulierten Lernen, wodurch sie die Wichtigkeit und den Wert eigener Entscheidung(sfindungsprozesse) auf Basis realistischer Selbsteinschätzung und Selbstevaluation erlernen. Gleichzeitig sollte Frontalunterricht durch interaktive Lehrformen ersetzt werden, idealerweise durch Aktivierung auf meta-kognitiver Ebene. Dies ist vielversprechend insbesondere, weil viele Studierende ihre eigenen mobilen Endgeräte in Lehrveranstaltungen bringen. Diese Geräte können als Second Screen für die neuen Lehrkonzepte verwendet werden. Auf diese Art kann dann eine verbesserte Lernerfahrung vermittelt werden. Die Grundidee ist simpel, nämlich in der Psychologie bewährte Didaktik-Konzepte durch die Mittel der Informatik zu unterstützen. Ein Beispiel dafür sind Audience Response Systeme, die hinlänglich im Rahmen von Vorlesungen untersucht worden sind. Andere Lehrformen wurden dabei jedoch unzureichend berücksichtigt, beispielsweise Tutorien. Ähnliche Überlegungen gelten natürlich auch für bewährte didaktische Konzepte wie Peer Instruction oder Betrachtungen in Form von Visible Learning. Deshalb präsentiert diese Dissertation einen experimentellen Ansatz, informationstechnische Lösungen für vor-Ort-Übungen anzubieten, nämlich Werkzeuge für Audience Response Systeme, Evaluationen, Lernbedarfsermittlung, Peer Discussion, sowie virtuelle interaktive Whiteboards. Die genannten Werkzeuge wurden unter Beachtung von Anonymitäts- und Beiläufigkeitsaspekten bereitgestellt. Sie erlauben einen Einblick in die Motivation der Studierenden Tutorien zu besuchen und die Werkzeuge zu nutzen, sowie ihr Nutzungsverhalten selbst. Die experimentellen Ergebnisse werden in ein erweiterbares Systemkonzept kombiniert, das drei Werkzeugklassen unterstützt: anonyme Peer Discussion, anonyme Kontrollwerkzeuge und Lernbedarfsermittlung. Für die ersten beiden Klassen liegen vielversprechende Ergebnisse vor, beispielsweise die notwendige Reduktion des Audience Response Systems auf eine Art Notbremse, die Vielseitigkeit von (Peer-)Discussion-Systemen, oder aber auch der Bedarf für eine retroaktive Deanonymisierung von initial anonymen Beiträgen. Der allgemein positive Einfluss der Werkzeugnutzung auf die Motivation an Tutorien teilzunehmen sowie den wahrgenommenen Wert der Tutorien werden abschließend diskutiert und durch verbesserte Abschlussklausurergebnisse untermauert.:List of Definitions, Theorems and Proofs List of Figures List of Tables Introduction and Motivation Part I: Propaedeutics 1 Working Theses 1.1 Definitions 1.2 Context of Working Theses and Definitions 2 Existing Concepts 2.1 Psychology 2.1.1 Self-Regulation and self-regulated Learning 2.1.2 Peer Instruction, Peer Discussion 2.1.3 Learning Process Supervision: Learning Demand Assessment 2.1.4 Cognitive Activation 2.1.5 Note on Gamification 2.1.6 Note on Blended Learning 2.2 Computer Science 2.2.1 Learning Platforms 2.2.2 Audience Response Systems (ARS) 2.2.3 Virtual Interactive Whiteboard Systems (V-IWB) 2.2.4 Cognisant Incidential Utilisation (CIU) 2.3 Appraisal 3 Related Work 3.1 Visible Learning 3.2 auditorium 3.3 Auditorium Mobile Classroom Service 3.4 ARSnova and other Audience Response Systems 3.5 Google Classroom 3.6 StackOverflow 3.7 AwwApp Part II: Proceedings 4 Global Picture and Prototype 4.1 Global Picture 4.2 System Architecture 4.2.1 Anonymous Discussion Means 4.2.2 Anonymous Control Facilities 4.3 Implementation 4.3.1 The Prototype 5 Investigated Tools 5.1 Note on Methodology 5.2 Anonymity 5.2.1 Methodology 5.2.2 Visible Learning Effects 5.2.3 Assertion 5.2.4 Experiments 5.2.5 Results 5.2.6 Conclusions 5.3 Learning Demand Assessment 5.3.1 Methodology 5.3.2 Visible Learning Effects 5.3.3 Tool Description 5.3.4 Assertion 5.3.5 Experiments 5.3.6 Results 5.3.7 Conclusions 5.4 Peer Discussion System 5.4.1 Methodology 5.4.2 Visible Learning Effects 5.4.3 Tool Description 5.4.4 Assertion 5.4.5 Experiments 5.4.6 Results 5.4.7 Conclusions 5.5 Virtual Interactive Whiteboard 5.5.1 Methodology 5.5.2 Visible Learning Effects 5.5.3 Tool Description 5.5.4 Assertion 5.5.5 Experiments 5.5.6 Results 5.5.7 Conclusions 5.6 Audience Response System and Emergency Brake 5.6.1 Methodology 5.6.2 Visible Learning Effects 5.6.3 Tool Description 5.6.4 Assertion 5.6.5 Experiments 5.6.6 Results 5.6.7 Conclusions 5.7 Evaluation System 5.7.1 Methodology 5.7.2 Visible Learning Effects 5.7.3 Tool Description 5.7.4 Assertion 5.7.5 Experiments 5.7.6 Results and Conclusion 6 Exam Outcome 7 Utilisation and Motivation 7.1 Prototype Utilisation 7.2 Motivational Aspects Part III: Appraisal 8 Lessons learned 9 Discussion 9.1 Working Theses’ Validity 9.2 Research Community: Impact and Outlook 9.2.1 Significance to Learning Psychology 9.3 Possible Extension of existing Solutions 10 Conclusion 10.1 Summary of scientific Contributions 10.2 Future Work Part IV: Appendix A Experimental Arrangement B Questionnaires B.1 Platform Feedback Sheet B.1.1 Original PFS in 2014 B.1.2 Original PFS in 2015 B.2 Minute Paper B.3 Motivation and Utilisation Questionnaires B.3.1 Motivation 2013 and 2014 B.3.2 Motivation 2015 B.3.3 Utilisation 2014 B.3.4 Utilisation 2015, Rev. I B.3.5 Utilisation 2015, Rev. II C References C.1 Auxiliary Means D Publications D.1 Original Research Contributions D.2 Student Theses E Glossary F Index G Milestones Acknowledgements
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TU-Spektrum 2/2004, Magazin der Technischen Universität Chemnitz

Steinebach, Mario, Friebel, Alexander, Häckel-Riffler, Christine, Tzschucke, Volker, Pollmer, Caroline, Horst, Gabriela, Brabandt, Antje, Reichold, Kathrin 15 December 2004 (has links) (PDF)
zweimal im Jahr erscheinende Zeitschrift über aktuelle Themen der TU Chemnitz, ergänzt von Sonderheft(en)
29

TU-Spektrum 2/2004, Magazin der Technischen Universität Chemnitz

Steinebach, Mario, Friebel, Alexander, Häckel-Riffler, Christine, Tzschucke, Volker, Pollmer, Caroline, Horst, Gabriela, Brabandt, Antje, Reichold, Kathrin 15 December 2004 (has links)
zweimal im Jahr erscheinende Zeitschrift über aktuelle Themen der TU Chemnitz, ergänzt von Sonderheft(en)

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