Online/offline signature schemes are useful in many situations, and two such scenarios are considered in this dissertation: bursty server authentication and embedded device authentication. In this dissertation, new techniques for online/offline signing are introduced, those are applied in a variety of ways for creating online/offline signature schemes, and five different online/offline signature schemes that are proved secure under a variety of models and assumptions are proposed. Two of the proposed five schemes have the best offline or best online performance of any currently known technique, and are particularly well-suited for the scenarios that are considered in this dissertation. To determine if the proposed schemes provide the expected practical improvements, a series of experiments were conducted comparing the proposed schemes with each other and with other state-of-the-art schemes in this area, both on a desktop class computer, and under AVR Studio, a simulation platform for an 8-bit processor that is popular for embedded systems. Under AVR Studio, the proposed SGE scheme using a typical key size for the embedded device authentication scenario, can complete the offline phase in about 24 seconds and then produce a signature (the online phase) in 15 milliseconds, which is the best offline performance of any known signature scheme that has been proven secure in the standard model. In the tests on a desktop class computer, the proposed SGS scheme, which has the best online performance and is designed for the bursty server authentication scenario, generated 469,109 signatures per second, and the Schnorr scheme (the next best scheme in terms of online performance) generated only 223,548 signatures. The experimental results demonstrate that the SGE and SGS schemes are the most efficient techniques for embedded device authentication and bursty server authentication, respectively.

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[pt] O foco do presente estudo são Batalhas de Rap femininas. Busca-se compreender metapragmáticas construídas em Batalhas de Rap femininas em dois canais do YouTube. A pesquisa parte do pressuposto histórico e social do Hip-hop, em que se inserem as Batalhas de Rap, como um ambiente de hegemonia masculina. A orientação teórica é da Sociolinguística Contemporânea, no âmbito da Linguística Aplicada, em interface com a Antropologia Linguística, Pragmática e Filosofia da Linguagem. A linguagem é entendida como performatização de sentidos. São utilizados conceitos de performance, performatividade, metapragmática, indexicalidade, entextualização e escala. A metodologia é da etnografia com a concepção de mobilidade onlineOffline em visão qualitativa e interpretativista. Nos dados analisados, as batalhas, ao viajarem para o YouTube, em vídeos, recebem reescalonamentos de significados estabilizados e a produção de outros. A palavra, como eixo central das batalhas, é um mecanismo de operação de significados em lutas que atravessam a vivência das MCs. As metapragmáticas apontam para causas coletivas de forma espiralar e trazem outras vozes para as rimas. O processo semiótico nas rimas das MCs busca produzir alianças das mulheres no rap. Os significados são avaliados pela audiência virtual em comentários, o que promove a construção reflexiva sobre as escalas. Vimos assim que as produções de sentido nas Batalhas de Rap femininas funcionam com ordens de indexicalidade, de forma a operar metapragmáticas sobre a prática cultural e sobre a vida. Os significados são entrelaçados por questões históricas, políticas, sociais e culturais sobre mulheres negras, lésbicas, paternidade, sexualidade, assédio, representatividade e religião. / [en] The focus of the present study is female Rap Battles. It seeks to understand metapragmatics built in female Rap Battles on two YouTube channels. The research lies in the historical and social assumptions of Hip-hop, in which Rap Battles are inserted, as an environment of male hegemony. Its theoretical orientation is Contemporary Sociolinguistics, within the scope of Applied Linguistics, in interface with Linguistic Anthropology, Pragmatics and Philosophy of Language. Language is understood as performance of meanings. Concepts of performance, performativity, metapragmatics, indexicality, entextualization and scale are used. The methodology adopted is ethnography with the concept of onlineOffline mobility in a qualitative and interpretive view. The analyzed data point out that when battles are posted on YouTube, stabilized meanings suffer a process of rescaling and meaning productions. The word, as the central axis of the battles, is a mechanism for operating meanings in struggles that cross the experience of the MCs. Metapragmatics point to collective causes in a spiral fashion and bring other voices to the rhymes. The semiotic process in the MCs rhymes seeks to produce alliances between women in rap. Meanings are evaluated by the virtual audience in comments, which promotes a reflective construction on the scales. Thus, we could notice the productions of meaning in female Rap Battles work with orders of indexicality, in order to operate metapragmatics on both cultural practice and life. Meanings are intertwined by historical, political, social and cultural issues about black women, lesbians, parenthood, sexuality, harassment, representation and religion.

Nous proposons dans cette thèse les approches de test pour la composition de services web. Nous nous intéressons aux test unitaire et d’intégration d’une orchestration de services web. L’aspect de vérification d’exécution en-ligne est aussi consideré. Nous définissons une plateforme de test unitaire pour l’orchestration de services web qui compose une architecture de test, une relation de conformité et deux approches de test basés sur le modèle de machine à l’états finis étendues temporisés: l’approche offline où les activités de test comme la génération de cas de test temporisé, l’exécution de test et l’assignement de verdict sont appliquées en séquentielle tandis que ces activités sont appliquées en parallèle dans l’approche online. Pour le test d’intégration d’une orchestration, nous combinons deux approches: active et passive.Au debut, l’approche active est utilisée pour activer une nouvelle session d’orchestration par l’envoi d’un message de requête SOAP. Après, tous les messages d’entré et de sortie de l’orchestration sont collectés et analysés par l’approche passive.Pour l’aspect de vérification d’exécution en-ligne, nous nous intéressons à la vérification d’une trace qui respecte un ensemble des constraintes, noté règles, ou pas. Nous avons proposé extendre le langage Nomad en définissant des constraintes sur chaque action atomique et un ensemble de corrélation de données entre les actions pour définir des règles pour le service web. Ce langage nous permet de définir des règles avec le temps futur et passé, et d’utiliser des opérations NOT, AND, OR pour combiner quelque conditions dans le contexte de la règle. Ensuite, nous proposons un algorithme pour vérifier l’exactitude d’une séquence des messages en parallèle avec le moteur de collecte de trace. / In this thesis, we propose the testing approaches for web service composition. We focus on unit, integrated testing of an orchestration of web services and also the runtime verification aspect. We defined an unit testing framework for an orchestration that is composed of a test architecture, a conformance relation and two proposed testing approaches based on Timed Extended Finite State Machine (TEFSM) model: offline which test activities as timed test case generation, test execution and verdict assignment are applied in sequential, and online which test activities are applied in parallel. For integrated testing of an orchestration, we combines of two approaches: active and passive. Firstly, active approach is used to start a new session of the orchestration by sending a SOAP request. Then all communicating messages among services are collected and analyzed by a passive approach. On the runtime verification aspect, we are interested in the correctness of an execution trace with a set of defined constraints, called rules. We have proposed to extend the Nomad language, by defining the constraints on each atomic action (fixed conditions) and a set of data correlations between the actions to define the rules for web services. This language allows us to define a rule with future and past time, and to use the operations: NOT, AND, OR to combines some conditions into a context of the rule. Afterwards, we proposed an algorithm to check correctness of a message sequence in parallel with the trace collection engine. Specifically, this algorithm verifies message by message without storing them.

With the proliferation of 21st century educational technologies, science teaching and learning with digitally acclimatized learners in secondary science education can be realized through an online Science-Technology-Society-Environment (STSE)-based issues approach. STSE-based programs can be interpreted as the exploration of socially-embedded initiatives in science (e.g., use of genetically modified foods) to promote the development of critical cognitive processes and to empower learners with responsible decision-making skills. This dissertation presents a case study examining the online environment of a grade 11 physics class in an all-girls’ school, and the outcomes from those online discursive opportunities with STSE materials. The limited in-class discussion opportunities are often perceived as low-quality discussions in traditional classrooms because they originate from an inadequate introduction and facilitation of socially relevant issues in science programs. Hence, this research suggests that the science curriculum should be inclusive of STSE-based issue discussions. This study also examines the nature of students’ online discourse and, their perceived benefits and challenges of learning about STSE-based issues through an online environment. Analysis of interviews, offline classroom events and online threaded discussion transcripts draws from the theoretical foundations of critical reflective thinking delineated in the Practical Inquiry (P.I.) Model. The PI model of Cognitive Presence is situated within the Community of Inquiry framework,encompassing two other core elements, Teacher Presence and Social Presence. In studying Cognitive Presence, the online STSE-based discourses were examined according to the four phases of the P.I. Model. The online discussions were measured at macro-levels to reveal patterns in student STSE-based discussions and content analysis of threaded discussions. These analyses indicated that 87% of the students participated in higher quality STSE-based discussions via an online forum as compared to in-class. The micro-level analysis revealed students to attain higher cognitive interactions with STSE issues. Sixteen percent of the students’ threaded postings were identified in the Resolution Phase 4 when the teacher intervened with a focused teaching strategy. This research provides a significant theoretical and pedagogical contribution to blended approach to STSE-based secondary science education. It presents a framework for teachers to facilitate students’ online discussions and to support learners in exploring STSE-based topics.

With the proliferation of 21st century educational technologies, science teaching and learning with digitally acclimatized learners in secondary science education can be realized through an online Science-Technology-Society-Environment (STSE)-based issues approach. STSE-based programs can be interpreted as the exploration of socially-embedded initiatives in science (e.g., use of genetically modified foods) to promote the development of critical cognitive processes and to empower learners with responsible decision-making skills. This dissertation presents a case study examining the online environment of a grade 11 physics class in an all-girls’ school, and the outcomes from those online discursive opportunities with STSE materials. The limited in-class discussion opportunities are often perceived as low-quality discussions in traditional classrooms because they originate from an inadequate introduction and facilitation of socially relevant issues in science programs. Hence, this research suggests that the science curriculum should be inclusive of STSE-based issue discussions. This study also examines the nature of students’ online discourse and, their perceived benefits and challenges of learning about STSE-based issues through an online environment. Analysis of interviews, offline classroom events and online threaded discussion transcripts draws from the theoretical foundations of critical reflective thinking delineated in the Practical Inquiry (P.I.) Model. The PI model of Cognitive Presence is situated within the Community of Inquiry framework,encompassing two other core elements, Teacher Presence and Social Presence. In studying Cognitive Presence, the online STSE-based discourses were examined according to the four phases of the P.I. Model. The online discussions were measured at macro-levels to reveal patterns in student STSE-based discussions and content analysis of threaded discussions. These analyses indicated that 87% of the students participated in higher quality STSE-based discussions via an online forum as compared to in-class. The micro-level analysis revealed students to attain higher cognitive interactions with STSE issues. Sixteen percent of the students’ threaded postings were identified in the Resolution Phase 4 when the teacher intervened with a focused teaching strategy. This research provides a significant theoretical and pedagogical contribution to blended approach to STSE-based secondary science education. It presents a framework for teachers to facilitate students’ online discussions and to support learners in exploring STSE-based topics.

Ultraprecision single point diamond turning is required to produce parts with sub-nanometer surface roughness and sub-micrometer surface profiles tolerances. These parts have applications in the optics industry, where tight form accuracy is required while achieving high surface finish quality. Generally, parts can be polished to achieve the desired finish, but then the form accuracy can easily be lost in the process rendering the part unusable. Currently, most mid to low spatial frequency surface finish errors are inspected offline. This is done by physically removing the workpiece from the machining fixture and mounting the part in a laser interferometer. This action introduces errors in itself through minute differences in the support conditions of the over constrained part on a machine as compared to the mounting conditions used for part measurement. Once removed, the fixture induced stresses and the part’s internal residual stresses relax and change the shape of the generally thin parts machined in these applications. Thereby, the offline inspection provides an erroneous description of the performance of the machine. This research explores the use of a single, high resolution, capacitance sensor to quickly and qualitatively measure the low to mid spatial frequencies on the workpiece surface, while it is mounted in a fixture on a standard ultraprecision single point diamond turning machine after a standard facing operation. Following initial testing, a strong qualitative correlation exists between the surface profiling on a standard offline system and this online measuring system. Despite environmental effects and the effects of the machine on the measurement system, the capacitive system with some modifications and awareness of its measurement method is a viable option for measuring mid to low spatial frequencies on a workpiece surface mounted on an ultraprecision machine with a resolution of 1nm with an error band of ±5nm with a 20kHz bandwidth. / Thesis / Master of Applied Science (MASc)