Pervasive computing implies the invisibility of the technology involved in providing ubiquity, such that technology is integrated into the environment and non-intrusive. In such a manner, computing and networking resources become diffused into physical environments, enabling users to exploit their provided functionalities such that functionality is distributed, enabling it to be controlled, monitored, managed, and extended beyond what it was initially designed to do. Moreover, computer awareness moves towards user-centricity, whereby systems seamlessly adapt to the characteristics, preferences, and current situations of users and their respective surrounding environments. Users exploit such functionalities in the form of a virtual device, whereby a collection of heterogeneous devices in the vicinity of the user are behaving as one single homogeneous device for the benefit of the user in solving some given task. This dissertation investigates the problem of dynamic composition and management of virtual devices for ad hoc multimedia service delivery and proposes an autonomous policy driven framework for virtual device management. The framework consists of a hierarchical structure of distributed elements, including autonomic elements, all working towards the self-management of virtual devices. The research presented in this dissertation addresses the functionalities of these components. More specifically, contributions are made towards the autonomous management of virtual devices, moving away from infrastructure based schemes with heavy user involvement to decentralized and zero touch (i.e., no user involvement) solutions. In doing so, the components and methodology behind a policy-driven autonomous framework for the dynamic discovery, selection, and composition of multimodal multi-device services are presented. The framework operates in an ad hoc network setting and introduces a Service Overlay Network (SON) based definition of a virtual device. Furthermore, device and service discovery, composition, integration, and adaptation schemes are designed for Mobile Ad hoc Network Environments (MANETs) enabling users to generate, on-the-fly, complex strong specific systems, embedding in a distributed manner, QoS models providing compositions that form the best possible virtual device at the time of need. Experimental studies are presented to demonstrate the performance of the proposed schemes.

Statement of the problem: The epithelial sodium channels (ENaC) play an important role in regulation of blood pressure (BP). Although the genes are identical in Dahl salt sensitive (S) and Dahl salt resistant (R) rats, expression of ENaC subunits is increased in kidneys of S rats on high salt diet. Intracerebroventricular (icv) infusion of ENaC blocker benzamil prevents Na+ induced hypertension. It was not known whether ENaC subunits are expressed in the brain and whether or not brain ENaC plays a role in regulation of [Na+] in CNS. Hypothesis: 1. Epithelial sodium channels are expressed in the brain. 2. Expression of ENaC is increased in the kidneys and brain of Dahl S rats on high salt diet. 3. ENaC in the brain contributes to regulation of [Na+] in the CSF and brain interstitium. Methods of investigation: We studied expression and distribution of the ENaC subunits and assessed the effects of icv infusion of Na+-rich aCSF in Wistar rats or high salt diet in Dahl S rats in different areas of the brain. Function of ENaC in the choroid plexus was evaluated by studying the effects of benzamil and ouabain on Na+ transport. Major findings: In Wistar rats, both mRNA and protein of all three ENaC subunits are expressed in brain epithelia and magnocellular neurons in the supraoptic (SON) and paraventricular (PVN) nucleus. ENaC abundance is higher on the apical versus basolateral membrane of choroid cells. Benzamil decreases Na+ influx into choroid cells by 20-30% and increases CSF [Na+] by ~8 mmol/L. Na+ rich aCSF increases apical membrane expression of βENaC in the choroid cells and of α and βENaC in basolateral membrane of ependymal cells, but has no effect on neuronal ENaC. Expression of ENaC is higher in choroid cells and SON of Dahl S versus R rats and the higher expression persists on a high salt diet. High salt attenuates the ouabain blockable efflux of Na+ from choroid cells and has no effect on CSF [Na+] in Dahl R rats. In contrast, high salt does not attenuate ouabain blockable efflux of 22Na+ and CSF [Na+] increases in Dahl S. Main Conclusion: ENaC in the brain contributes to Na+ transport into the choroid cells and appear to be involved in reabsorption of Na+ from the CSF. Aberrant regulation of Na+ transport and of Na+K+ATPase activity, might contribute to increases in CSF [Na+] in Dahl S rats on high-salt diet. ENaC in magnocellular neurons may contribute to enhanced secretion of mediators such as ‘ouabain’ leading to sympathetic hyperactivity in Dahl S rats.

High salt intake contributes to the development of hypertension in salt-sensitive humans and animals and the mechanistic causes are poorly understood. In Dahl salt-sensitive (S) but not salt-resistant (R) rats, high salt diet increases cerebrospinal fluid (CSF) [Na+] and activates an aldosterone-mineralocorticoid receptor-epithelial sodium channel-endogenous ouabain (MR-ENaC-EO) neuromodulatory pathway in the brain that enhances the activity of sympatho-excitatory angiotensinergic and glutamatergic pathways, leading to an increase in sympathetic nerve activity (SNA) and blood pressure (BP). We hypothesize that high salt diet in Dahl S rats enhances Ang II release in the paraventricular nucleus (PVN), causing a decrease in local nitric oxide (NO) action and an increase in local glutamate release thereby elevating SNA, BP and heart rate (HR). The present study evaluated the effects of agonists or blockers of MR, ENaC, EO, nitric oxide synthase (NOS) or glutamate and AT1-receptors on the BP and HR responses to acute infusions of Na+ rich aCSF, intracerebroventricularly (icv), or in the PVN of Dahl S, R or Wistar rats or to high salt diet in Dahl S and R rats. In Wistar rats, aldosterone in the PVN enhanced the BP and HR responses to infusion of Na+ rich aCSF in the PVN, but not in the CSF, and only the enhancement was prevented by blockers of MR, ENaC and EO in the PVN. AT1-receptor blockers in the PVN fully blocked the enhancement by aldosterone and the responses to infusion of Na+ rich aCSF icv, or in the PVN. Na+ rich aCSF in the PVN caused larger increases in BP and HR in Dahl S vs. R rats and the responses to Na+ were fully blocked by an AT1-receptor blocker in the PVN. BP and HR responses to a NOS blocker in the PVN were the same, but L-NAME enhanced Na+ effects more in Dahl R than S rats. High salt diet attenuated increases in BP from L-NAME in the PVN of Dahl S but not R rats. AT1 and glutamate receptor blockers candesartan and kynurenate in the PVN decreased BP in Dahl S but not R rats on high salt diet. At the peak BP response to candesartan, kynurenate in the PVN further decreased BP whereas candesartan did not further decrease BP at the peak BP response to kynurenate. Our findings indicate that both an acute increase in CSF [Na+] and high salt intake in Dahl S rats increases AT1-receptor activation and decreases NO action in the PVN thereby contributing to the pressor responses to Na+ and presumably, to dietary salt-induced hypertension. The increased BP response to AT1-receptor activation in the PVN of Dahl S is mediated by enhanced local glutamate receptor activation. An MR-ENaC-EO pathway in the PVN can be functionally active and further studies need to assess its role in Dahl S rats on high salt intake.

Enhancing primary care is key to the Canadian health care reform. Considered as an indicator of primary care access and quality, hospitalisations for ambulatory care sensitive (ACS) conditions are commonly reported by Canadian organisations as sentinel events signaling problems with the delivery of primary care. However, the literature calls for further research to identify what lies behind ACS hospitalisation rates in regions with a predominantly urban population benefiting from universal access to health care. A theoretical model was built and, using an ecological design, multiple regressions were implemented to identify which neighbourhood characteristics explained the socio-economic gradient in ACS hospitalisation rates observed in Ottawa. Among these neighbourhoods, healthy behaviour and - to a certain extent - health status were significantly associated with ACS hospitalisation rates. Evidence of an association with primary care accessibility was also signaled for the more rural neighbourhoods. Smoking prevention and cessation campaigns may be the most relevant health care strategies to push forward by policy makers hoping to prevent ACS hospitalisations in Ottawa. From a health care equity perspective, targeting these campaigns to neighbourhoods of low socio-economic status may contribute to closing the gap in ACS hospitalisations described in this current study. Reducing the socio-economic inequalities of neighbourhoods would also contribute to health equity.

In this era of the Internet of Things and Big Data, a proliferation of connected devices continuously produce massive amounts of fast evolving streaming data. There is a need to study the relationships in such streams for analytic applications, such as network intrusion detection, fraud detection and financial forecasting, amongst other. In this setting, it is crucial to create data mining algorithms that are able to seamlessly adapt to temporal changes in data characteristics that occur in data streams. These changes are called concept drifts. The resultant models produced by such algorithms should not only be highly accurate and be able to swiftly adapt to changes. Rather, the data mining techniques should also be fast, scalable, and efficient in terms of resource allocation. It then becomes important to consider issues such as storage space needs and memory utilization. This is especially relevant when we aim to build personalized, near-instant models in a Big Data setting. This research work focuses on mining in a data stream with concept drift, using an online bagging method, with consideration to the memory utilization. Our aim is to take an adaptive approach to resource allocation during the mining process. Specifically, we consider metalearning, where the models of multiple classifiers are combined into an ensemble, has been very successful when building accurate models against data streams. However, little work has been done to explore the interplay between accuracy, efficiency and utility. This research focuses on this issue. We introduce an adaptive metalearning algorithm that takes advantage of the memory utilization cost of concept drift, in order to vary the ensemble size during the data mining process. We aim to minimize the memory usage, while maintaining highly accurate models with a high utility. We evaluated our method against a number of benchmarking datasets and compare our results against the state-of-the art. Return on Investment (ROI) was used to evaluate the gain in performance in terms of accuracy, in contrast to the time and memory invested. We aimed to achieve high ROI without compromising on the accuracy of the result. Our experimental results indicate that we achieved this goal.

Pressure sensitive adhesives (PSAs) are polymeric materials with versatile applications in industrial and consumer products such as protective films, product labels, masking tape, and sticky notes, to name a few applications. World demand for emulsion–based products is on the rise due to worldwide legislation on solvent emissions. In order to completely replace emulsion-based PSAs with their solvent-based counterpart, the property modification of emulsion-based PSAs is required. The use of nanomaterials to modify polymer properties is well established. The aim of this thesis was to use cellulose nanocrystals (CNCs) as property modifiers for emulsion-based PSAs. CNCs are recognized as a highly efficient reinforcement nanofiller. Owing to their environmentally friendly characteristics, low density, high aspect ratio, non-toxicity, and abundant availability, the application of CNCs in composite materials is gaining increasing attention. In this thesis, the inclusion of CNCs in emulsion-based PSAs was carried out through in situ emulsion polymerization and blending technique. To the best of our knowledge, there is limited information about the synthesis of CNC/PSAs nanocomposites via in situ emulsion polymerization and the evaluation of their mechanical performance. The addition of CNCs to the polymerization formulation caused latex instability due to the negatively charged surfaces of the CNCs. After numerous attempts to overcome the stability issues, a stable polymerization formulation and protocol were developed. CNC/PSAs were synthesized via in situ seeded-semi batch emulsion polymerization, which is a common commercial production pathway for PSAs. The mechanical performance of the resulting PSA nanocomposite films, namely, shear strength, tack, and peel strength, was evaluated at several CNC loadings. All three PSA adhesive properties were simultaneously enhanced with increasing CNC loading. The inclusion of CNCs into the films increased their hydrophilicity. Consequently, the PSA films’ improved wettability on a stainless steel substrate imparted greater tack and peel strength. The blending of the CNCs with a base latex also led to improved adhesive properties. However, the property modification through blending was not as effective as that for the CNC/PSA films synthesized via in situ emulsion polymerization. Thus, CNCs are safe nanomaterials that have been shown to provide remarkable property enhancement of emulsion-based PSA films at low loadings (1wt%).

This work has four aims: (i) to provide an overview of the current debate about the semantics of knowledge attributions, i.e. sentences of the form ⌜S knows that Φ⌝; (ii) to ground the debate in a single semantic-pragmatic framework; (iii) to identify a methodology for describing the semantics of knowledge attributions; (iv) to go some way towards describing the semantics of knowledge attributions in light of this methodology, and in particular to defend moderate invariantist semantics against its main current rivals. Aims (i) and (ii) are largely clarificatory; in §1 I set out a single semantic-pragmatic framework and over the course of this work show that it can be modified to explain and distinguish the various theories of the semantics of knowledge attributions currently on offer. Aim (iii) is also met in §1. I argue that a theory of the semantics of knowledge attributions T must be able to account for at least some ordinary speakers’ intuitions about the felicity or infelicity of utterances of the sentence ⌜S knows that Φ⌝ (felicity intuitions) purely in terms of its semantics. I also identify a number of theoretical considerations about knowledge and argue that if T conflicts with any one of these considerations, we should presume that T is false. Aim (iv) is met over the course of this work. According to moderate invariantism ⌜S knows that Φ⌝ is true if and only if S confidently believes the proposition expressed by , this proposition is true and S’s epistemic position with respect to this proposition meets a moderately high epistemic standard. In §§2 – 5 I argue that the main current rivals to moderate invariantism – attributor contextualism, contrastivism, subject-sensitive invariantism and assessor relativism – conflict with at least one of the theoretical considerations identified in §1. In §6 I argue that moderate invariantism accounts for some ordinary speakers’ felicity intuitions purely in terms of the semantics of ⌜S knows that Φ⌝; I also argue that it is consistent with all of the theoretical considerations identified in §1. Moreover, in §§2 – 6 I argue that no theory is capable of accounting for all felicity intuitions purely in terms of the semantics of ⌜S knows that Φ⌝, and that only moderate invariantism can successfully explain why speakers have all of these intuitions. In §7 I conclude that moderate invariantism correctly describes of the semantics of knowledge attributions, or at least does so better than its main current rivals.

After the end of the NASA space shuttle programme, there has been resurgence of interest in developing a single stage-to-orbit spacecraft. The key technology to realize this dream is the airbreathing scramjet engine. The scramjet concept has been around for decades, but much work is still needed in order to eliminate the remaining obstacles to develop a practical working prototype of the engine. Many such obstacles are related to the inlet which functions as the main compression unit for the engine. Typically, a high speed inlet is designed to function properly in a single flight condition. Such an inlet would experience adverse flow conditions related to various shock-shock interactions, viscous effects, shock-boundary layer interactions, and many other flow phenomena at off-design conditions. The traditional mechanism to mitigate the adverse flow conditions is by varying the inlet geometry at off-design conditions. There are still gaps in understanding the behaviour of inlets at off-design conditions and the effectiveness of variable geometry as inlet flow control. This is partly due to complex flow diagnostics setup, which limits the type, quantity and quality of information that can be extracted from the inlet flow. The first objective of this thesis was to develop a global inlet measurement system that can provide an abundance of information on inlet flow. The pressure sensitive paint method was employed together with other methods to provide comprehensive understanding on inlet flow characteristics. Calculation of Mach number at the isolator exit using the isolator sidewall pressure map was successfully demonstrated. The measurement of Mach number at the isolator exit has allowed for performance of the inlet to be calculated without the need for intrusive flow diagnostics tools used by previous researchers. The global measurement system was then employed to investigate the characteristics of the scramjet inlet operating at various off-design conditions. Complex shock structures were observed at the inlet cowl entrance as the angle-of-attack was increased. The relationship of flow quality and inlet performance was examined and discussed. General improvements on the inlet performance were obtained if the size of separation on the compression ramp was reduced. The inlet was also observed to perform poorly when compression shocks impinged on the inner cowl surface. Cowl deflections were demonstrated to be effective in controlling the internal flow of the inlet and improving its performance. An exploratory study on the role of micro-vortex generators to control boundary layer separation on scramjet inlets has been included as well. Strategies for optimizing an inlet at off-design conditions were analysed, and it was found that any variable geometry combination must maintain high throat-to-freestream Mach number ratio in order to preserve high inlet performance.

Orientador: Julio Roberto Bartoli / Dissertação (mestrado) - Universidade Estadual de Campinas, Faculdade de Engenharia Quimica / Made available in DSpace on 2018-08-07T21:53:07Z (GMT). No. of bitstreams: 1 Zanin_AileenNicoleFowler_M.pdf: 11356850 bytes, checksum: cf01903240aa482d9b8d8f3559af3823 (MD5) Previous issue date: 2006 / Resumo: Adesivo Sensíveis à Pressão (PSA) são adesivos poliméricos usados principalmente em fitas e etiquetas. De modo geral, existem três tipos de adesivos PSA: a base de solvente, a base d'água e "hot melt". Os adesivos a base de solvente apresentam algumas limitações como flamabilidade e toxicidade, mas ainda são amplamente usados, devido às propriedades finais que apresentam, como boa adesividade a substratos polares c boa adesão com alguns plásticos. Geralmente, os compostos poliméricos para PSA utilizam cargas minerais devido à redução de custo e às propriedades finais que os PSA podem apresentar, como propriedades dielétricas, resistência à umidade e tensão na ruptura. Por outro lado, nanocompósitos estão mostrando grandes vantagens em várias aplicações poliméricas, melhorando suas propriedades térmicas, mecânicas e retardância à chama. Adesivos PSA nanocompósitos a base de solvente foram preparados pelo processo de esfoliação-solução de compostos a base de borracha natural e argilas organicamente modificadas. Um planejamento fatorial de experimentos, 22 com replicata, foi utilizado para verificar a influência dos fatores da composição: concentração e tipos de argilas modificadas, nas propriedades físicas dos adesivos. Um composto adesivo de referencia (PSA convencional) foi também preparado utilizando CaCOH3, carga de uso comum nessas formulações. Os adesivos foram caracterizados através das suas propriedades adesivas (coesão ou "shear", adesão ao aço ou "peel" ,tlato à superfície ou "tack") gel e resistência à propagação de chama. A maioria dessas propriedades apresentou significância estatística em ao menos um dos fatores de composição estudados, tipo ou concentração de nanoargila. Os ensaios de resistência á propagação de chama mostraram melhoria nas propriedades de resistência à propagação da chama em todos os adesivos com argilas modificadas, comparados ao composto de referência. Análises TGA indicaram o mesmo comportamento de variação de massa em função da temperatura para lodos os adesivos. As análises DMTA dos adesivos mostraram diferenças entre os dois tipos de argilas modificadas quanto às suas Tg. Nas análises XRD dos adesivos não foram identificados picos de difração característicos das argilas, talvez devido à diluição das amostras ou até à desejada esfoliação. Nas análises de SEM dos compostos adesivos observou-se uma tênue forma lamelar devido às argilas e as análises EDS dos compostos indicaram a presença de Si e Al, constituintes da argila modificada / Abstract: Pressure sensitive adhesives (PSA) are polymeric adhesives used for mainly in tapes and labels. Usually, there are 3 types of PSA: solvent based, water based and hot melt. Solvent based adhesives have few limitations, like flammability and toxicity, but they are still often used, due to their properties as good adhesion to polar substrates and good bonding with some plastics. The compounds for pressure sensitive adhesives, in general, use fillers due to cost reduction and properties they can give, like dielectric properties, water resistance and tensile strength. On the other side, nanocomposites are showing great advantages on several polymers applications improving thermal resistance, flame retardancy and mechanical properties. Nanocomposites for solvent-based adhesives were prepared by an exfoliation-solution process of natural rubber and organically modified clay compounds. A Design of Experiment (DOE). 22 with replication, was used to verify the influence of compounding factors; concentration and grades of nanoclays.A control adhesive compound was prepared using CaCO3, very common filler for adhesive fonnulations. The PSA were characterized by their adhesive properties (cohesion or shear, adhesion to steel or peel test, tack), gel and flammability. Almost all these properties showed statistical significance at least for one of the compounding factors, grade or concentration of nanociay. The flammability tests showed an improvement on the flame retardancy properties for all the nanoclays adhesives compared to the control compound. TGA analyses showed the same pattern of mass reduction as a function of temperature for all the adhesives. DMTA showed differences between the 2 kinds of nanoclays regarding Tg. XRD analyses did not show any diffraction peak related to the clays, likely due to the diluted samples or even to an exfoliation. SEM analyses showed a slightly lamellar pattern of clays and EDS analyses of the compounds confirmed the presence of Si and Al, elements of the nanoclays / Mestrado / Ciencia e Tecnologia de Materiais / Mestre em Engenharia Química

Submitted by Renata Lopes (renatasil82@gmail.com) on 2015-12-14T11:30:12Z No. of bitstreams: 1 mariadiomaradasilva.pdf: 1683129 bytes, checksum: 1d7d2f1086e3675e5fb98e7ddf56c333 (MD5) / Approved for entry into archive by Adriana Oliveira (adriana.oliveira@ufjf.edu.br) on 2015-12-14T15:49:40Z (GMT) No. of bitstreams: 1 mariadiomaradasilva.pdf: 1683129 bytes, checksum: 1d7d2f1086e3675e5fb98e7ddf56c333 (MD5) / Made available in DSpace on 2015-12-14T15:49:40Z (GMT). No. of bitstreams: 1 mariadiomaradasilva.pdf: 1683129 bytes, checksum: 1d7d2f1086e3675e5fb98e7ddf56c333 (MD5) Previous issue date: 2015-04-14 / A minha constituição de espaço de vida e formação durante a infância, adolescência e fase adulta no lugar reconhecido como favela foi a força motriz que gerou em mim inquietações, interesses e motivações para desenvolver esta pesquisa. Neste trabalho, busquei apresentar uma pesquisa que procurou mostrar o desenvolvimento linguístico e a produção dos saberes de crianças e adolescentes moradores do bairro onde vivi, no qual um projeto denominado Curumim está inserido, desenvolvido pela Associação Municipal de Apoio Comunitário – AMAC, da Prefeitura Municipal de Juiz de Fora, no Estado de Minas Gerais. O objetivo foi investigar se as oficinas de teatro, como as do Curumim, ofereciam contribuições efetivas para o desenvolvimento da competência comunicativa dos alunos. O caminho para a coleta de dados durante as oficinas aconteceu por meio das anotações no diário de campo, questionários de crenças, questionário socioeconômico e gravação eletrônica em áudio. Esses materiais instrumentalizaram a coleta dos dados e fizeram parte de uma amostra que constituíram o corpus que compôs essa pesquisa. A oficina de teatro não é uma aula de português tradicional de língua portuguesa, no entanto, enquanto gênero textual, o teatro atende a diversos aspectos que podem auxiliar um trabalho voltado para uma reflexão sobre a língua, por meio dos princípios da Sociolinguística Educacional, principalmente contemplando um trabalho através de uma pedagogia culturalmente sensível (BORTONI-RICARDO, 2004) capaz de levar até as crianças dessa comunidade, possibilidades de ampliar sua competência de linguagem. Além disso, as oficinas trazem consigo características que são essencialmente próprias do contexto sociocultural das crianças, pois, as atividades realizadas partem daquilo que é significativo para elas. / My constitution of life space and my formation during childhood, adolescence and adulthood at a slum was the driving force that created in me concerns, interests and motivation in order to develop this research. In this work, I aimed at presenting the development of a research which sought to show the linguistic development and the production of children’s and adolescent’s knowledge living in the neighborhood where I lived, where there is a social project called Curumim developed by Associação Municipal de Apoio Comunitário – AMAC, by Juiz de Fora Mayor, Minas Gerais. The goal was to investigate whether the acting classes, such as the ones offered by Curumim, would offer effective contributions for the development of the communicative competence of students. The route to collect the data during the classes occurred by the notes on the field diary, beliefs questionnaires; socioeconomic questionnaires and audio electronic recording. These resources equipped the data collection and took part in a sample that constituted the corpus which composed this research. The acting class is not a traditional Portuguese class, however, as a textual genre, it includes several aspects that are able to help to develop a work inclined to reflect about the language, through the principles of Educational Sociolinguistics, mainly contemplating a work through a culturally sensitive pedagogy (BORTONI-RICARDO, 2004) able to take to the children from this community possibilities of enlarging their language competence. Furthermore, the classes bring characteristics that are essentially specific of children’s sociocultural context, because the activities are conducted from what is significative for them.