La RFID (RadioFrequency Identification) est une technologie d'identification intélligente qui connait de nombreux développements car ses domaines d'applications vont de la traçabilité de produits et d'animaux jusqu'au contrôle d'accès et la sécurité en passant par le médical. D'un point de vue technique, la RFID est une communication de type “Wireless” qui utilise des fréquences spécifiques. Les recherches aujourd'hui concernent la RFID aux fréquences UHF et microondes ainsi que le développement de tags à bas-coût. C'est dans ce contexte que se situe cette thèse. Nous avons étudié la réalisation et la miniaturisation d'antennes sur matériaux à bas-coût tels que les plastiques et les papiers. Nous avons également montré la faisabilité d'antennes performantes, en UHF et en microondes, utilisant des encres conductrices. Toutes ces études nous ont permis de concevoir un tag démonstrateur intégrant une antenne et une puce RFID.

Numerical models are powerful and widely used tools for environmental prediction; however, any model prediction contains errors due to imperfect model parameterizations, insufficient model resolution, numerical errors, imperfect initial and boundary conditions etc. A variety of approaches is applied to quantify, correct and minimize these errors including skill assessments, bias correction and formal data assimilation. All of these require observations and benefit from comprehensive data sets. In this thesis, two aspects related to the quantification and correction of errors in biological ocean models are addressed: (i) A new bias correction method for a biological ocean model is evaluated, and (ii) a novel approach for expanding the set of typically available phytoplankton observations is assessed. The bias correction method, referred to as frequency-dependent nudging, was proposed by Thompson et al. (Ocean Modelling, 2006, 13:109-125) and is used to nudge a model only in prescribed frequencies. A desirable feature of this method is that it can preserve high frequency variability that would be dampened with conventional nudging. The method is first applied to an idealized signal consisting of a seasonal cycle and high frequency variability. In this example, frequency-dependent nudging corrected for the imposed seasonal bias without affecting the high-frequency variability. The method is then applied to a non-linear, 1 dimensional (1D) biogeochemical ocean model. Results showed that application of frequency-dependent nudging leads to better biogeochemical estimates than conventional nudging. In order to expand the set of available phytoplankton observations, light measurements from sensors attached on grey seals where assessed to determine if they provide a useful proxy of phytoplankton biomass. A controlled experiment at Bedford Basin showed that attenuation coefficient estimates from light attenuation measurements from seal tags were found to correlate significantly with chlorophyll. On the Scotian Shelf, results of the assessment indicate that seal tags can uncover spatio-temporal patterns related to phytoplankton biomass; however, more research is needed to derive absolute biomass estimates in the region.

This thesis communicates a new approach for the future Library system using secure NFC technology. Today we can use NFC and Android based mobile phones to build modern library system in which user will instead of standing in the queue can directly borrow and return books. The NFC technology which will use in this thesis is capable of storing small amount of information. This storage will be used for maintaining the books records. Although the NFC works in close proximity but still there are possibilities of attacks. Due to contact less communication the victim cannot notice the attacks. There are different types of attacks which can occur including modification of data and listening to the communication by unknown user. Therefore in this thesis the author will look into how one can protect the system from these kinds of at-tacks. The motivation behind the thesis is to introduce scalable cloud based infrastructure as a backbone Library. Current systems using bar code technology are not secure. Therefore an infrastructure needs to be built which includes cloud based server for key distribution and data storage. Furthermore, this thesis includes a study of the encryption and decryption schemes for close proximity communications. A new novel algorithm has been introduced and implemented as an encryption scheme for this thesis work. The Huffman scheme has been modified and 16 bit keys have been used for the key exchange. The new approach is compared with the existing techniques and found that it is reliable as compared to other techniques.

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.

Diss. (sammanfattning) Stockholm : Karolinska institutet, 2007. / Härtill 4 uppsatser.

Diss. (sammanfattning) Uppsala : Univ., 2003. / Härtill 4 uppsatser.

Thesis (doctoral)--Techn. Hochsch., Aachen, 2003.

Thesis (Ph. D.)--University of Washington, 2006. / Vita. Includes bibliographical references (leaves 106-119).

Submitted by Emanuel Varela Cardoso (emanuel.varela@ufcg.edu.br) on 2018-09-11T19:22:35Z No. of bitstreams: 1 ALYSSON FILGUEIRA MILANEZ – TESE (PPGCC) 2018.pdf: 2014097 bytes, checksum: 2ec510f3d6024481b6be80c8b19942d7 (MD5) / Made available in DSpace on 2018-09-11T19:22:35Z (GMT). No. of bitstreams: 1 ALYSSON FILGUEIRA MILANEZ – TESE (PPGCC) 2018.pdf: 2014097 bytes, checksum: 2ec510f3d6024481b6be80c8b19942d7 (MD5) Previous issue date: 2018-05-25 / Capes / Embora contratos no estilo de programação por contratos (DBC) tragam precisão para expressar o comportamento do código, desenvolvedores são resistentes ao seu uso. Há várias razões para isto, tais como a dificuldade na produção de contratos ou o trabalho de manter os contratos consistentes com o código em evolução. Por outro lado, Javadoc é uma abordagem comumente usada para documentar programas Java. Mesmo assim, comentários Javadoc não servem para a checagem automática de conformidade devido à ambiguidade inerente à linguagem natural. Neste trabalho, procuramos minimizar a distância entre contratos e Javadoc, estimulando a adoção de DBC a partir de duas contribuições principais; primeiro, propomos uma extensão ao sistema de tags do Javadoc (CONTRACTJ DOC) para possibilitar a integração de contratos na notação de comentários; então, propomos uma abordagem para geração de contratos a partir de comentários em linguagem natural (CONTRACT SUGGESTOR). Nós realizamos três avaliações: primeiro, avaliamos a aplicabilidade e a compreensibilidade de CONTRACTJ DOC. Como resultados, detectamos inconsistências entre a documentação Javadoc e o código fonte. A maioria dos contratos que escrevemos foram checagens de valores limítrofes para parâmetros e repetições de expressões de retorno de métodos. Além disso, a legibilidade dos comentários percebida pelos desenvolvedores não diferiu significativamente entre as abordagens, o que é promissor, dado que contratos são usualmente classificados como difíceis de ler. Segundo, avaliamos a qualidade dos contratos gerados por CONTRACT SUGGESTOR verificando a taxa de falsos positivos gerados. Como resultado, são gerados mais contratos corretos para non-null do que para relational, devido a quantidade de instâncias de comentários para cada propriedade. Por fim, realizamos estudos de caso com JMLOK2 e C ONTRACTOK – CONTRACTOK é uma extensão da abordagem de J MLOK2 para o contexto C#/Code Contracts. Primeiro, usamos JMLOK2 para verificar os contratos gerados automaticamente por CONTRACT SUGGESTOR; depois usamos as ferramentas para verificar 24 sistemas de código aberto (12 para cada ferramenta). As ferramentas detectaram 188 não-conformidades, sendo 72 problemas de pós-condição e 61 de invariante; as causas prováveis mais comuns foram Pré-condição fraca (91) e Erro de código (56). Com isso, objetivamos motivar a adoção de DBC como forma de aprimorar o projeto dos programas, e por consequência, sua qualidade geral. / Contracts in Design by Contract style bring about preciseness for expressing the code behavior; however, developers are resistant to their use. There are several likely reasons for this, such as the trouble to conceive good, useful contracts, or the burden of maintaining contracts consistent with the evolving code. On the other hand, Javadoc is a common way of documenting Java programs. Nevertheless, Javadoc comments do not serve to an automated conformance checking due to ambiguity issues inherent to the natural languages. In this work, we try to minimize the distance between contracts and Javadoc, fostering DBC adoption by means of two main contributions; first, we propose an extension to the Javadoc tagging system (C ONTRACTJD OC) for allowing the integration of contracts into the comments notation; then, we propose an approach for automatically generating contracts based on natural language code commentary (CONTRACTSUGGESTOR). We perform three evaluations: first, we evaluate the applicability and comprehensibility of C ONTRACTJD OC. As results, we detected inconsistencies between the documentation available by means of Javadoc comments and the source code. The majority of the contracts we could write from the comments remains between common-case and repetitive with the code. Moreover, developers’ impression about the readability of comments did not differ significantly, which is promising, as contracts are usually regarded as hard to read – one reason for its non-adoption. Then, we evaluate the quality of contracts generated by CONTRACTSUGGESTOR by analyzing the false positives rate. As result, the approach generates more correct contracts for non-null than for relational, due to the number of comment instances for each property. Finally, we perform case studies with J MLOK2 and C ONTRACTOK – C ONTRACTOK is an extension of JMLOK2 for C#/Code Contracts context. First, we used J MLOK2 for conformance checking the contracts automatically generated; then, we run the tools over 24 open-source systems (12 with each tool). The tools detected 188 nonconformances. From those, 72 are postcondition and 61 are invariant problems; with respect to likely causes manually established, Weak precondition (91) and Code error (56) are the most commons. With this, we aim to promote DBC adoption as a way for improving the design of the projects, and consequently, their quality in general.

Apesar do intenso interesse na regulação metabólica e evolução das vias produtoras de ATP, o porquê de a maioria dos microorganismos multicelulares metabolizarem glicose através de respiração, ao invés da fermentação, ainda permanece sem resposta. Um desses microorganismos é o fungo celulolítico Trichoderma reesei (Hypocrea jecorina. Usando análise EST e microarrays de cDNA, foi estabelecido, em T. reesei, que a expressão dos genes que codificam as enzimas do ciclo de TCA é programada de tal modo a favorecer a oxidação de piruvato pelo ciclo de TCA, ao invés de sua redução a etanol, através da fermentação. Além disso, os resultados indicam que acetaldeído pode ser convertido a acetato, e não a etanol, prevenindo a regeneração de NAD+, um produto chave requerido para o metabolismo anaeróbico. Os estudos também mostram que a maquinaria de controle regulatório por glicose, foi, provavelmente, objeto de pressão evolutiva, a qual dirigiu o fluxo metabólico à respiração, e não à fermentação. / Despite the intense interest in the metabolic regulation and evolution of the ATP-producing pathways, the long-standing question of why most multicellular microorganisms metabolize glucose by respiration rather than fermentation remains unanswered. One such microorganism is the cellulolytic fungus Trichoderma reesei (Hypocrea jecorina). Using EST analysis and cDNA microarrays, we find that in T. reesei expression of the genes encoding the enzymes of the TCA is programmed in a way that favors the oxidation of pyruvate via the TCA cycle rather than its reduction to ethanol by fermentation. Moreover, the results indicate that acetaldehyde may be channeled into acetate rather than ethanol, thus preventing the regeneration of NAD+, a pivotal product required for anaerobic metabolism. The studies also point out that the regulatory machinery controlled by glucose was most probably the target of evolutionary pressure that directed the flow of metabolites into respiratory metabolism rather than fermentation.