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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.
271

Συστήματα διαχείρισης περιεχομένου και σημαντικός ιστός / Content management systems and semantic web

Νάκος, Κωνσταντίνος 24 January 2012 (has links)
Ένα μεγάλο ποσοστό ιστότοπων παράγεται και συντηρείται με χρήση Συστημάτων Διαχείρισης Περιεχομένου (Content Management Systems – CMS), τα οποία, εκτός από περιεχόμενο κειμένου, διαχειρίζονται και δομημένα δεδομένα. Από την άλλη, ο Σημαντικός Ιστός αν και έχει αρχίσει να γίνεται πραγματικότητα παραμένει σε εμβρυϊκό στάδιο σε σχέση με τον παραδοσιακό Ιστό. Η σύγκλιση των δύο κόσμων θα μπορούσε να αποφέρει τεράστια οφέλη και να πυροδοτήσει την ταχύτερη εξάπλωση του Σημαντικού Ιστού. Στην παρούσα διπλωματική εργασία καταγράφονται και μελετώνται τα πιο διαδεδομένα εργαλεία Σημαντικού εμπλουτισμού CMS, καθώς και μια σειρά από CMS που φέρουν εγγενή χαρακτηριστικά Σημαντικού Ιστού. Τέλος, υλοποιείται μια πρότυπη δικτυακή πύλη με τη χρήση της έκδοσης 7 του CMS Drupal, η οποία ενσωματώνει χαρακτηριστικά Σημαντικού Ιστού στον πυρήνα της (όπως αυτόματη ενσωμάτωση στις σελίδες που παράγονται του νεοσύστατου πρότυπου RDFa). / Currently a large number of Web sites are driven by Content Management Systems (CMS), which manage not only textual content but also structured data. On the other hand, even though Semantic Web is beginning to materialize, it is still dwarfed by the traditional Web. The convergence of the two worlds could produce significant benefits and trigger a faster spread of the Semantic Web. In the current diploma thesis, prevalent CMS semantic enrichment tools and a series of Semantic CMS are thoroughly examined. Finally, an experimental web portal is developed using CMS Drupal’s version 7, which integrates Semantic Web features in its core (such as the automatic embedding of the emergent RDFa standard in the pages created).
272

Correlation of optical anisotropy with structural changes in Ge2Sb2Te5

Shanmugam, Janaki January 2018 (has links)
Ge<sub>2</sub>Sb<sub>2</sub>Te<sub>5</sub> (GST) is an established phase-change material that undergoes fast reversible transitions between amorphous and crystalline states with a high electro-optical contrast, enabling applications in non-volatile optical and electronic memories and optically-switchable structured metamaterials. This work demonstrates that optical anisotropy can be induced and recorded in pure and doped GST thin films using circularly polarised light (CPL), opening up the possibility of controlled induction of anisotropic phase transition in these and related materials for optoelectronic and photonic applications. While the amorphous-to-crystalline phase transition in GST has generally been understood to proceed via a thermal mechanism, significant optical anisotropy (measured by circular dichroism (CD) spectroscopy in this work) strongly suggests that there is an electronic athermal component of the phase change induced by the handedness of circularly polarised nanosecond laser pulses and implies the existence of chiral structures or motifs. Optically active and inactive regions in the films have also been studied using X-ray and electron diffraction and spectroscopic techniques in order to obtain a structural picture that can be correlated to the optical changes observed and the findings offer surprising evidence of the nature of the phase transition. Regions exhibiting higher CD signal intensities were found to be mostly amorphous with elemental phase separation observed within modified surface features. Several mechanisms are proposed for the observed phenomena, including the retention of chiral crystalline fragments in laser- irradiated and melt-quenched amorphous regions, which could explain the results of CD spectroscopy. This may be extended to other material systems and harnessed in potential metamaterials, plasmonics, photonics or chiroptical applications.
273

Wickrpedia : Integrering av sociala tjänster

Ekström, Johan January 2006 (has links)
The web has evolved much through the years. From being a place where author and reader were clearly distinguished, it now invites everyone to take part in the development of both content and technology. Social services are central in what is called Web 2.0. Wikis, blogs and folksonomies are all examples of how the users and their communities are key to the development of services. Collaborative writing, tags and API:s are central. Social services are given an extra dimension through integration. The purpose of this study was to investigate whether it was possible to integrate an encyclopedia with a photosharing service. The issue was whether it was possible to find relevant images to the article they were connected to. The method for examining the issue was to create a service which functions was investigated through user tests. Wickrpedia was created, which is an integration of Wikipedia and Flickr. Wikipedia is an encyclopedia in the shape of a wiki, while Flickr is used to store, organize and share photos. The result shows that the images added someting to the encyclopedia; it became more entertaining and pleasant and the users’ knowledge was increased. The relevance of the images was good. The service can and should be improved. The conclusion is still that the service worked well and was seen as an improvement by the users. / Webben har förändrats mycket de senaste åren. Från att tidigare haft en tydlig uppdelning mellan läsare och författare inbjuds nu alla att delta i utvecklingen av både innehåll och teknik. Sociala tjänster är det centrala i det som benämns Web 2.0. Wikis, bloggar och folksonomies är alla exempel på hur användarna och deras gemenskap är nyckeln till utveckling av tjänster. Kollaborativt skrivande, taggar och API:er är centrala. Sociala tjänster får en ytterligare dimension genom integrering. Denna studies syfte var att utreda hur det gick att integrera ett uppslagsverk med en fotodelningstjänst. Frågan är om det gick att göra på ett sådant sätt att bilderna hade relevans för de artiklar de kopplades till. Metoden för att utreda frågan var att skapa en tjänst vars funktion undersöktes med hjälp av användartester. Wickrpedia skapades, vilket är en intregrering av Wikipedia och Flickr. Wikipedia är en encyklopedi i form av en wiki, medan Flickr används för att förvara, organisera och dela med sig av bilder. Resultatet visar att bilderna tillförde något till uppslagsverket; det blev roligare och trevligare och användarna fick en ökad kunskap. Relevansen hos bilderna var god. Tjänsten har brister, och den går att vidareutveckla. Slutsatsen var ändå att tjänsten fungerade och var en förbättring för användarna.
274

SW podpora pro znalostní objekty / Knowledge management system in the form of knowledge network

Vojíř, Stanislav January 2012 (has links)
Knowledge is one of the most important values of companies, work-teams and other organizations. It is one of competitive advantages and so it is important to share the knowledge among individuals in the organization. The discipline of knowledge management deals with the issue of systematic work with knowledge and sharing for several decades. The sharing and finding of knowledge should be supported via suitable software tools, currently using the Internet network. This work deals with problematic of knowledge management from the viewpoint of different methods of software support. The text approaches the problem of sharing of knowledge in a hypertext form. The problem is solved not only on theoretical base, but also from the viewpoint of system design and implementation. The knowledge is saved in the form of "knowledge network" based on text contents, authors and keywords. The data are saved in the form of RDF graph using PHP and ARC2 Framework. The developed system will be used not only for support of dealing with knowledge in the courses of project management at University of Economics in Prague.
275

Distribuované zpracování rozsáhlých dat na platformě Java / Distributed Big Data Processing on the Java Platform

Tutko, Jakub January 2018 (has links)
This thesis is focused on the distributed Big Data processing on the Java platform, together with graph databases. It analyses several graph database distributions and the possibilities to connect them to the Apache Hadoop system for distributed data processing. For the purpose of testing database solutions effectiveness, the thesis outcome is an application, which is downloading data from social networks Twitter and Facebook. It is able to write and analyse data with two different database frameworks which are Halyard and HGraphDB.
276

Metody extrakce informací / Methods of Information Extraction

Adamček, Adam January 2015 (has links)
The goal of information extraction is to retrieve relational data from texts written in natural human language. Applications of such obtained information is wide - from text summarization, through ontology creation up to answering questions by QA systems. This work describes design and implementation of a system working in computer cluster which transforms a dump of Wikipedia articles to a set of extracted information that is stored in distributed RDF database with a possibility to query it using created user interface.
277

Transformace ontologií / Transformations of Ontologies

Kopecký, Marek January 2014 (has links)
This master's thesis describes importing the ontology in language OWL 2 into the internal structures of 4A annotation server. It is concerned in anonymous nodes, for example in anonymous classes or anonymous properties. The solution was to use the library The OWL API for import ontology. The solution also allows automatic generation of names to anonymous classes and properties.
278

Distribuovaný informační systém založený na sémantických technologiích / Distributed Information System Based on Semantic Technology

Havlena, Jan January 2010 (has links)
This master's thesis deals with the design of a distributed information system, where the data distribution is based on semantic technologies. The project analyzes the semantic web technologies with the focus on information exchange between information systems and the related terms, mainly ontologies, ontology languages and the Resource description framework. Furthermore, there is described a proposal an ontology which is used to describe the data exchanged between the systems and the technologies used to implement distributed information system. The most important of them are Java Server Faces and Sesame.
279

Sémantický web v CMS systémech / Semantic Web in Content Management Systems

Vrána, Michal January 2010 (has links)
This masters thesis deals with the Semantic Web, its link to existing Web and the technologies, that produce it. It also deals with its current use in practice, further examines the deployment in web content management systems and proposes semantic extensions for the Kentico CMS.
280

Development and characterization of two new tools for plant genetic engineering: A CRISPR/Cas12a-based mutagenesis system and a PhiC31-based gene switch

Bernabé Orts, Juan Miguel 16 December 2019 (has links)
[ES] La mejora genética vegetal tiene como objetivo la obtención de plantas con rasgos mejorados o características novedosas que podrían ayudar a superar los objetivos de sostenibilidad. Para este fin, la biotecnología vegetal necesita incorporar nuevas herramientas de ingeniería genética que combinen una mayor precisión con una mayor capacidad de mejora. Las herramientas de edición genética recientemente descubiertas basadas en la tecnología CRISPR/Cas9 han abierto el camino para modificar los genomas de las plantas con una precisión sin precedentes. Por otro lado, los nuevos enfoques de biología sintética basados en la modularidad y la estandarización de los elementos genéticos han permitido la construcción de dispositivos genéticos cada vez más complejos y refinados aplicados a la mejora genética vegetal. Con el objetivo final de expandir la caja de herramientas biotecnológicas para la mejora vegetal, esta tesis describe el desarrollo y la adaptación de dos nuevas herramientas: una nueva endonucleasa específica de sitio (SSN) y un interruptor genético modular para la regulación de la expresión transgénica. En una primera parte, esta tesis describe la adaptación de CRISPR/Cas12a para la expresión en plantas y compara la eficiencia de las variantes de Acidaminococcus (As) y Lachnospiraceae (Lb) Cas12a con Streptococcus pyogens Cas9 (SpCas9) descritos anteriormente en ocho loci de Nicotiana benthamiana usando expresión transitoria. LbCas12a mostró la actividad de mutagénesis promedio más alta en los loci analizados. Esta actividad también se confirmó en experimentos de transformación estable realizados en tres plantas modelo diferentes, a saber, N. benthamiana, Solanum lycopersicum y Arabidopsis thaliana. Para este último, los efectos mutagénicos colaterales fueron analizados en líneas segregantes sin la endonucleasa Cas12a, mediante secuenciación del genoma descartándose efectos indiscriminados. En conjunto, los resultados muestran que LbCas12a es una alternativa viable a SpCas9 para la edición genética en plantas. En una segunda parte, este trabajo describe un interruptor genético reversible destinado a controlar la expresión génica en plantas con mayor precisión que los sistemas inducibles tradicionales. Este interruptor, basado en el sistema de recombinación del fago PhiC31, fue construido como un dispositivo modular hecho de partes de ADN estándar y diseñado para controlar el estado transcripcional (encendido o apagado) de dos genes de interés mediante la inversión alternativa de un elemento regulador central de ADN. El estado del interruptor puede ser operado externa y reversiblemente por la acción de los actuadores de recombinación y su cinética, memoria y reversibilidad fueron ampliamente caracterizados en experimentos de transformación transitoria y estable en N. benthamiana. En conjunto, esta tesis muestra el diseño y la caracterización funcional de herramientas para la ingeniería del genómica y biología sintética de plantas que ahora ha sido completada con el sistema de edición genética CRISPR/Cas12a y un interruptor genético reversible y biestable basado en el sistema de recombinación del fago PhiC31. / [CAT] La millora genètica vegetal té com a objectiu l'obtenció de plantes amb trets millorats o característiques noves que podrien ajudar a superar els objectius de sostenibilitat. Amb aquesta finalitat, la biotecnologia vegetal necessita incorporar noves eines d'enginyeria genètica que combinen una major precisió amb una major capacitat de millora. Les eines d'edició genètica recentment descobertes basades en la tecnologia CRISPR/Cas9 han obert el camí per modificar els genomes de les plantes amb una precisió sense precedents. D'altra banda, els nous enfocaments de biologia sintètica basats en la modularitat i l'estandardització dels elements genètics han permès la construcció de dispositius genètics cada vegada més complexos i sofisticats aplicats a la millora genètica vegetal. Amb l'objectiu final d'expandir la caixa d'eines biotecnològiques per a la millora vegetal, aquesta tesi descriu el desenvolupament i l'adaptació de dues noves eines: una nova endonucleasa específica de lloc (SSN) i un interruptor genètic modular per a la regulació de l'expressió transgènica . En una primera part, aquesta tesi descriu l'adaptació de CRISPR/Cas12a per a l'expressió en plantes i compara l'eficiència de les variants de Acidaminococcus (As) i Lachnospiraceae (Lb) Cas12a amb la ben establida Streptococcus pyogens Cas9 (SpCas9), en vuit loci de Nicotiana benthamiana usant expressió transitòria. LbCas12a va mostrar l'activitat de mutagènesi mitjana més alta en els loci analitzats. Aquesta activitat també es va confirmar en experiments de transformació estable realitzats en tres plantes model diferents, a saber, N. benthamiana, Solanum lycopersicum i Arabidopsis thaliana. Per a aquest últim, els efectes mutagènics col·laterals van ser analitzats en línies segregants sense l'endonucleasa Cas12a, mitjançant seqüenciació completa del genoma i descartant efectes indiscriminats. En conjunt, els resultats mostren que LbCas12a és una alternativa viable a SpCas9 per a l'edició genètica en plantes. En una segona part, aquest treball descriu un interruptor genètic reversible destinat a controlar l'expressió gènica en plantes amb major precisió que els sistemes induïbles tradicionals. Aquest interruptor, basat en el sistema de recombinació del bacteriòfag PhiC31, va ser construït com un dispositiu modular fet de parts d'ADN estàndard i dissenyat per controlar l'estat transcripcional (encès o apagat) de dos gens d'interès mitjançant la inversió alternativa d'un element regulador central d'ADN. L'estat de l'interruptor pot ser operat externa i reversiblement per acció dels actuadors de recombinació i la seva cinètica, memòria i reversibilitat van ser àmpliament caracteritzats en experiments de transformació transitòria i estable en N. benthamiana. En conjunt, aquesta tesi mostra el disseny i la caracterització funcional d'eines per a l'enginyeria del genòmica i biologia sintètica de plantes que ara ha sigut completat amb el sistema d'edició genètica CRISPR/Cas12a i un interruptor genètic biestable i reversible basat en el sistema de recombinació del bacteriòfag PhiC31. / [EN] Plant breeding aims to provide plants with improved traits or novel features that could help to overcome sustainability goals. To this end, plant biotechnology needs to incorporate new genetic engineering tools that combine increased precision with higher breeding power. The recently discovered genome editing tools based on CRISPR/Cas9 technology have opened the way to modify plant¿s genomes with unprecedented precision. On the other hand, new synthetic biology approaches based on modularity and standardization of genetic elements have enabled the construction of increasingly complex and refined genetic devices applied to plant breeding. With the ultimate goal of expanding the toolbox of plant breeding techniques, this thesis describes the development and adaptation to plant systems of two new breeding tools: a site-specific nuclease (SSNs), and a modular gene switch for the regulation of transgene expression. In a first part, this thesis describes the adoption of the SSN CRISPR/Cas12a for plant expression and compares the efficiency of Acidaminococcus (As) and Lachnospiraceae (Lb) Cas12a variants with the previously described Streptococcus pyogens Cas9 (SpCas9) in eight Nicotiana benthamiana loci using transient expression experiments. LbCas12a showed highest average mutagenesis activity in the loci assayed. This activity was also confirmed in stable genome editing experiments performed in three different model plants, namely N. benthamiana, Solanum lycopersicum and Arabidopsis thaliana. For the latter, off-target effects in Cas12a-free segregating lines were discarded at genomic level by deep sequencing. Collectively, the results show that LbCas12a is a viable alternative to SpCas9 for plant genome engineering. In a second part, this work describes the engineering of a new reversible genetic switch aimed at controlling gene expression in plants with higher precision than traditional inducible systems. This switch, based on the bacteriophage PhiC31 recombination system, was built as a modular device made of standard DNA parts and designed to control the transcriptional state (on or off) of two genes of interest by alternative inversion of a central DNA regulatory element. The state of the switch can be externally and reversibly operated by the action of the recombination actuators and its kinetics, memory, and reversibility were extensively characterized in N. benthamiana using both transient expression and stable transgenics. Altogether, this thesis shows the design and functional characterization of refined tools for genome engineering and synthetic biology in plants that now has been expanded with the CRISPR/Cas12a gene editing system and the phage PhiC31-based toggle switch. / Bernabé Orts, JM. (2019). Development and characterization of two new tools for plant genetic engineering: A CRISPR/Cas12a-based mutagenesis system and a PhiC31-based gene switch [Tesis doctoral no publicada]. Universitat Politècnica de València. https://doi.org/10.4995/Thesis/10251/133055 / TESIS

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