This work proposes a two-stage method that reconstructs the map of a scene from tagged photographs of that scene. In the first stage, several methods are proposed that transform tag data from the photographs into an intermediary distance matrix. These methods are compared against each other. In the second stage, an approach based on the physical mass-spring system is proposed that transforms the distance matrix into a map. This approach is compared against and outperforms MDS-MAP(P) when given human tagged input photographs. Experiments are carried out on two test datasets, one with 67 tags, and the other with 19. An evaluation method is described and the optimal overall reconstruction generates maps with accuracies of 47% and 66% respectively for the two test datasets, both scoring roughly 40% higher than a random reconstruction. The map reconstruction method is applied to three sample datasets and the resulting maps are qualitatively evaluated.

This work proposes a two-stage method that reconstructs the map of a scene from tagged photographs of that scene. In the first stage, several methods are proposed that transform tag data from the photographs into an intermediary distance matrix. These methods are compared against each other. In the second stage, an approach based on the physical mass-spring system is proposed that transforms the distance matrix into a map. This approach is compared against and outperforms MDS-MAP(P) when given human tagged input photographs. Experiments are carried out on two test datasets, one with 67 tags, and the other with 19. An evaluation method is described and the optimal overall reconstruction generates maps with accuracies of 47% and 66% respectively for the two test datasets, both scoring roughly 40% higher than a random reconstruction. The map reconstruction method is applied to three sample datasets and the resulting maps are qualitatively evaluated.

Large-scale expressed sequence tags (ESTs) in Atlantic salmon (Salmo salar) are examined to answer questions regarding salmonid transcriptomes. ESTs represent raw and incomplete gene sequences that need to be read, assembled and analyzed with computer software. The goal of this thesis was to develop an automatically curated and publicly accessible set of annotated full-length genes, representing a near-complete transcript set for Salmo salar. In turn, these genes provide the framework for studies in gene expression, conservation, and molecular evolution. The work presented here also touches on the results of a molecular evolution study, as an example of how full-length gene identification can be used to answer biological questions. Previous to this study, a limited number of Atlantic salmon cDNA libraries and ESTs were known. To further the goal of determining complete gene sequences, highly enriched full-length cDNA libraries and full-length libraries were created and sequenced, resulting in the ability to identify a large number of full-length reference genes. Together, all libraries represent a diverse pool of transcriptome sequences for Salmo salar. The goal of producing an accurate large-scale full-length gene set on a duplicated genome is not trivial. Complete systems for this objective do not readily exist. EST sequencing, EST assembly, and data storage, are just a few of the initial computational issues that are addressed. Once these issues are resolved, the multi-step workflow of full-length gene determination is described. The final challenge involving the development of a concise and universally accessible system for visualization is discussed. The resulting computational framework that has been developed is shown to be able to handle the intricacies and the size of a duplicated salmonid genome. It has been largely accepted that Atlantic salmon have undergone a recent genome duplication. Gene paralogs provide one source of evidence for this event. Analysis of paralogs revealed signatures of asymmetric evolution possibly due to relaxation of selective pressure. This thesis provides a complete Bioinformatics analysis pipeline to analyze and to visualize a set of full-length reference genes for Atlantic salmon. Using full-length genes as a framework, the topic of molecular evolution was addressed to show evidence of asymmetrical evolution among gene duplicates. The full-length reference genes, along with ESTs and all putative transcripts, have been made publicly available. These results serve as a valuable genomic resource for next-generation sequencing and for all other salmonid research endeavours. / Graduate

Thesis (M. Sc.)--University of Canterbury, 2006. / Typescript (photocopy). Includes bibliographical references (p. 143-145). Also available via the World Wide Web.

No description available.

Durch die wachsende Bedeutung des Onlinehandels und der Zunahme an Benutzer-generierten Inhalten werden neue Ansätze benötigt, um Konsumenten bei ihrer Entscheidungsfindung zu unterstützen. Wie Studien zeigen, werden im Onlinehandel häufig Kundenrezensionen und Gesamtbewertungen eingesetzt. Allerdings sind diese beiden Werkzeuge für die Entscheidungsfindung von Konsumenten nur begrenzt hilfreich. Gesamtbewertungen zeigen zwar eine oberflächliche Zufriedenheit der Kunden, geben jedoch keine Auskunft über die Bewertung bestimmter Produktaspekte, z.B. den Tragekomfort von Kopfhörern. Diese Aspekte werden von Kunden häufig in Rezensionen beschrieben, welche jedoch aufgrund ihrer unstrukturierten Weise nicht automatisiert aufbereitet werden können. Konsumenten sind daher gezwungen Rezensionen zu lesen und die darin diskutierten Merkmale manuell zu extrahieren. Die vorliegende Arbeit leistet mehrere Beiträge zur Adressierung des oben genannten Problems und beschäftigt sich dabei mit der Konzeptionierung, Evaluierung und Dienst-orientierten Bereitstellung einer interaktiven Entscheidungshilfe für den E-Commerce. Zunächst wird anhand einer empirischen Untersuchung der umsatzstärksten Onlineshops aus Deutschland der aktuelle Einsatz von Social Media Features analysiert. Dabei zeigt sich, dass die o.g. Problematik von keinem untersuchten Onlineshop adressiert wird. Ein weiterer Beitrag ist der Entwurf sowie die prototypische Implementierung einer interaktiven Entscheidungshilfe mit der Bezeichnung Rated Tags. Rated Tags erlaubt die Benutzer-generierte Definition von bewertbaren Schlagwörtern (Tags) und kombiniert dabei Methoden aus den Bereichen Social Tagging und Bewertungssysteme. Eine nachfolgende Evaluierung des Konzepts im Rahmen einer Anwenderstudie zeigt, dass der Einsatz von Rated Tags die Entscheidungsqualität verbessern sowie den Entscheidungsaufwand von Konsumenten reduzieren kann. Zur Optimierung des Lösungsansatzes wird dann ein Ensemble-Klassifikator aus dem Bereich des überwachten Lernens zur semiautomatisierten Vereinheitlichung von semantisch ähnlichen Tags entworfen, prototypisch implementiert und evaluiert. Die Ergebnisse der Evaluierung zeigen, dass die Leistung des Klassifikators den aktuellen Stand der Technik übersteigt. Als Abschluss der Arbeit wird ein Modell mit der Bezeichnung Rated Tags as a Service vorgestellt, welches die Service-orientierte Bereitstellung des Rated Tags-Ansatzes für Onlineshops oder Bewertungsportale beschreibt.

L’un des enjeux de la lutte contre le cancer réside dans la compréhension de l’hétérogénéité de la maladie. Le but de notre travail a été d’explorer l’hétérogénéité des cellules cancéreuses du point de vue de la séquence d’ARN messager. Les ESTs (ou Expressed Sequence Tags) d’origine humaine ont été alignées aux séquences de référence ARNm. Les alignements ont été exploités de manière à mesurer les variations de séquence des ESTs issues de tissus tumoraux ou non tumoraux à chaque position de chaque transcrit. L’analyse statistique mise en place a consisté à identifier les positions pour lesquelles les variations de séquence, i.e. substitutions, insertions et délétions, sont différentes entre les ESTs d’origine tumorale et les ESTs d’origine non tumorale. L’étude bioinformatique s’est d’abord concentrée sur 17 transcrits abondamment exprimés avant d’être étendue à l’ensemble du transcriptome. Elle a ensuite été réalisée sur les ESTs murines. Les résultats montrent que l’hétérogénéité des transcrits cancéreux est plus grande que celle des tissus sains. Ainsi, l’infidélité de transcription est augmentée au cours de la carcinogénèse. Ce résultat bioinformatique a été validé par différentes approches biologiques. Tout d’abord, le clonage puis le séquençage d’un ARN provenant d’une tumeur pulmonaire humaine et présentant une délétion prédite de manière bioinformatique ont été réalisés, et ce, en l’absence de mutation somatique. Ensuite, l’identification par spectrométrie de masse d’un variant protéique issu de la traduction d’un ARN dont le codon stop est substitué en triplet codant a été possible. Enfin, l’intérêt de rechercher dans le sérum de patients cancéreux la présence d’anticorps dirigés contre des protéines issues de la traduction d’ARNm infidèles a été démontré. Ainsi, l’infidélité de transcription est un phénomène augmenté dans le cancer et responsable d’une partie de l’hétérogénéité des cellules cancéreuses. L’intérêt de cette découverte réside dans les perspectives nouvelles qu’elle offre en termes de compréhension des mécanismes de carcinogénèse et en termes de diagnostic de la maladie / One of the aim of the fight against cancer is to understand the heterogeneity of cancer cells. The goal of our work has been to explore cancer cell mRNA heterogeneity. ESTs (Expressed Sequence Tags) extracted from normal and cancer tissues have been aligned to mRNA reference sequences. This allowed identification of non-random sequence variations that occurred at statistically significant increased rates in cancer compared to normal libraries. This analysis first focused on 17 abundant transcripts and was next extended to whole human genome, as well as to that of Mus musculus. The results show an increase of transcription infidelity events in cancer tissues. Three types of events occur, i.e. base substitutions, deletions and insertions. Bioinformatics results have been validated through different biological methods. First, the cloning and sequencing of mRNA from lung cancer human with a deletion occurring at bioinformatically predicted position in absence of somatic mutation has been achieved. Then, mass spectrometry analysis confirmed the existence of protein variants resulting from translation of mRNA bypassing stop codon. Finally, we showed that transcription infidelity peptides contain specific epitopes of immunoglobulins ; detection of changes in immunoglobulins in patients with cancers opens a novel path toward early stage cancer diagnosis. This increased transcription infidelity in cancer contributes to the heterogeneity of cancer cells. This finding opens novel perspectives and strategies toward understanding carcinogenesis and diagnostic of the disease

Malgré les nombreux avantages que procure la RFID, son déploiement demeure freiné par plusieurs facteurs aussi bien économiques, que technologiques. Parmi ces freins, on peut citer le coût encore trop élevé des tags, le manque de fiabilité et de sécurité dans les informations contenues dans la puce RFID mais aussi les aspects «recyclage» des tags. Dans cette thèse nous nous focalisons sur le développement de tags RFID sans puce, qui représentent une nouvelle famille de tags bas coût. Avec cette technologie, l'information est extraite à partir de la réponse électromagnétique du tag qui dépend uniquement de sa géométrie. Différentes solutions ont été développées dans le but d'augmenter la quantité d'informations, de réduire la surface du tag ou encore d'améliorer la robustesse de détection. Des considérations pratiques tel que l'aspect réalisation sur substrat papier, le développement d'un système de détection bas coût, ou encore l'aspect mesure dans un environnement réel on été adressés afin d'établir une preuve de concept. Des travaux sur la réalisation de capteurs RFID sans puce et sur le moyen de rendre un tag sans puce reconfigurable sont présentés en guise de perspective. / Despite the many benefits of RFID, deployment is still hindered by several factors both economic and technological. Among these barriers include the cost of tags still too high, lack of reliability and security in the information contained in the RFID chip but also aspects "recycling" of tags. In this thesis we focus on the development of chipless RFID tag, which represent a new family of low cost tags. With this technology, information is extracted from the electromagnetic response of the tag which depends only on its geometry. Various solutions have been developed to increase the amount of information, reduce the surface of the tag or to improve the robustness of detection. Practical considerations such as realization using paper substrate, the development of a low cost detection system, or measurements in a real environment have been addressed in order to establish proof of concept. The last works concerning chipless RFID sensor or about the way to make a chipless tag fully reconfigurable are presented as a perspective.

This study contributes to the academic literature concerning social tag systems for digital libraries, addressing the identified information gap from the user’s perspective. It defines social tagging tools and tests users’ perceptions about possible practices. Moreover, it evaluates the effect when using social tagging systems in digital libraries, to assess whether such a system enhances the search process, and to identify whether there is any significant relationship between using social tagging systems in digital libraries and user satisfaction. Although developments in the field of social tags have been significant in recent years, there remains an open question regarding their usability, particularly in the context of digital libraries. Therefore, there is a need for further investigation, exploration and evaluation, and so this work contributed to this by exploring the usability of social tagging in digital libraries in terms of accuracy for research, user satisfaction and adoptability. For this study, Saudi students were given the opportunity to use the system in the United Kingdom, and their experiences, and opinions regarding ease of use and adoptability were then analysed to determine if they would assist digital libraries in Saudi Arabia to achieve their educational goals and to ensure user numbers would not decrease. A quantitative approach and a qualitative approach were combined to collect and analyse the data used in this research. The two approaches were conducted in sequential phases. In the first quantitative phase, assessment measures were administrated to Saudi students using library websites while studying in the UK. Data was collected from 175 participants, and statistical analysis was conducted using SPSS. Cross tabulation was also used to describe the numerical data and a chi-square analysis was conducted to determine the relationship between the various study variables. In the follow-up qualitative phase, semi-structured interviews were undertaken with 15 Saudi students, to explore the proposed hypothesis in depth. This data was then thematically analysed. Results concerning the usability of social tagging in digital libraries obtained in western universities cannot be generalised to Saudi Arabian universities, because the context of Saudi Arabia differs culturally and academically (Alsurehi & Al Youbi, 1014). To address this, the study utilised a sample of Saudi Arabian students, who had had the opportunity to experience using social tags while studying abroad, specifically in the United Kingdom. Their experience might potentially be very important and this research could be considered a first attempt to examine the usability of social tags in digital libraries. Since to date few empirical studies have directly addressed the usability issues raised here in Saudi Arabia, this research also offers a contribution in this area. In addition, although this study relates to the Saudi perspective, the findings can also be considered valuable to Arab countries sharing similar cultural and academic traditions.

No description available.