In a radio frequency (RF) system, the front-end of a radio receiver consists of an active antenna arrangement with a conducting mode antenna along with an active circuit. This arrangement helps avoid losses and SNR degradation due to the use of a coaxial cable. The active circuit is essentially an impedance matching network and a low noise amplification (LNA) stage. The input impedance of the antenna is always different from the source impedance required to be presented at the LNA input for maximum power gain and this gives rise to undesired reflections at the antenna-LNA junction. This necessitates a matching network that provides the impedance matching between the antenna and the LNA at a central frequency (CF). From the Friis formula it is seen that the total noise figure (NF) of the system is dependent on the noise figure and gain of the first stage. So, by having an LNA that provides a high gain (typically >15 dB) which inserts minimum possible noise (desirably < 1 dB), the overall noise figure of the system can be maintained low. The LNA amplifies the signal to a suitable power level that will enable the subsequent demodulation and decoding stages to efficiently recover the original signal. The antenna and the LNA can be matched with each other in two possible ways. The first approach is the traditional method followed in RF engineering where in both the antenna and LNA are matched to 50 W terminations and connected to each other. In this classical method, the antenna and LNA are matched to 50 W at the CF and does not take into account the matching at other frequencies in the operation range. The second approach employs a co-design method to match the antenna and LNA without a matching network or with minimum possible components for matching. This is accomplished by varying one or more parameters of either the antenna or LNA to control the impedances and ultimately achieve a matching over a substantial range of frequencies instead at the CF alone. The co-design method is shown to provide higher gain and a lower NF with reduced number of components, cost and size as compared to the classical method. The thesis work presented here is a study, design and manufacturing of an antenna-LNA module for a wide frequency range of 1.7 GHz – 2.7 GHz to explore the gain and NF improvements in the co-design approach. Planar micro strip patch antennas and GaAs E-pHEMT transistor based LNA’s are designed and the matching and co-design are simulated to test the gain and NF improvements. Furthermore, fully functional prototypes are developed with Roger R04360 substrate and the results from simulations and actual measurements are compared and discussed.

O BRAMS (Brazilian developments on the Regional Atmospheric Modelling System) é o sistema utilizado pelo CPTEC/INPE para previsão climática no Brasil. Este projeto de doutorado contribui para a modernização do código desse sistema a partir da implementação e avaliação de um framework para coprojeto de hardware/software do módulo da dinâmica do modelo climático BRAMS. Foi conduzido um estudo do código do BRAMS para verificar quais trechos poderiam ser acelerados em hardware. Com isso foram desenvolvidos kernels usando Intel OpenCL para serem executados em dispositivos programáveis do tipo FPGA. Este estudo utilizou o suporte e recursos do programa da Intel HARP (Heterogeneous Architecture Research Platform), que disponibilizou uma infraestrutura de computação heterogênea com processadores Xeon com um FPGA Arria 10 integrado. Foram conduzidos dois estudos de caso em que os resultados sugerem que é possível portar uma aplicação climática para uma máquina heterogênea que utiliza CPU e FPGA. Porém, para obter um desempenho satisfatório nessa nova arquitetura faz-se necessário domínio dos recursos disponíveis no Intel OpenCL para programar a máquina heterogênea e a aplicação alvo deve possuir uma estrutura de código que favoreça a execução de tais estruturas. Apesar do desempenho com o FPGA Arria 10 não ter sido superior ao do sistema executando apenas em Intel Xeon, o ganho em eficiência de energia justifica a migração do código para esta nova plataforma. Além disso, o framework desenvolvido possibilitará futuras implementações do BRAMS visando uma arquitetura heterogênea como alvo. / BRAMS (Brazilian developments on the Regional Atmospheric Modelling System) is the system used by CPTEC/INPE for climate forecast in Brazil. This PhD project contributes to the improvement of the code of this system from implementation and evaluation of a hardware/software codesign framework of the dynamics module of the BRAMS climate model. A study of the source code was conducted to verify what parts can be accelerated with hardware. Kernels were developed using Intel OpenCL and they were executed in programmable devices of the type FPGA. This study used resources of the Intel HARP program (Heterogeneous Architecture Research Platform). HARP provided an infrastructure of heterogeneous computation with Xeon processors including an Arria 10 FPGA integrated. The results from three case studies conducted suggest that it is possible to carry a climate application to a heterogeneous machine that uses CPU and FPGA. However, to obtain a satisfactory performance in this new architecture it is necessary to master the available resources in Intel OpenCL to program the heterogeneous machine and the target application must have a code structure that favors the execution of such structures. Although the performance was not higher than the system running only in CPU, the gain in energy efficiency justifies the migration of the code to this new platform.

A demanda por novas tecnologias, melhoria de segurança e conforto para veículos urbanos cresceu consideravelmente nos últimos anos, motivando a indústria na criação de sistemas destinados ao apoio de motoristas (ADAS - Advanced Driver Assistance Systems). Este fato contribuiu para o desenvolvimento de diversos sistemas embarcados na área automobilística destacando-se, à prevenção de colisão a pedestres por veículos. Através do avanço em diversas pesquisas, começaram a circular pelas ruas veículos com sistemas anticolisão e com navegação autônoma. Contudo, para alcançar objetivos cada vez mais desafiadores, os projetistas precisam de ferramentas que permitam unir tecnologias e conhecimentos de áreas distintas de forma eficiente. Nesse contexto, há uma demanda para a construção de sistemas que aumentem o nível de abstração da modelagem de projetos para o processamento de imagens em sistemas embarcados e assim, possibilitando uma melhor exploração do espaço de projetos. A fim de contribuir para minimizar este problema, este trabalho de pesquisa demonstra o desenvolvimento de um framework para coprojeto de hardware e software específico para a construção de sistemas ADAS que utilizam visão computacional. O Framework visa facilitar o desenvolvimento dessas aplicações permitindo a exploração o espaço de projeto (DSE - Design Space Exploration), e assim contribuindo para um ganho de desempenho no desenvolvimento de sistemas embarcados quando comparados à construção totalmente de um modo manual. Uma das características deste projeto é a possibilidade da simulação da aplicação antes da síntese em um sistema reconfigurável. Os principais desafios deste sistema foram relacionados à construção do sistema de intercomunicação entre os diversos blocos de Propriedade Intelectual (IP) e os componentes de software, abstraindo do usuário final inúmeros detalhes de hardware, tais como gerenciamento de memória, interrupções, cache, tipos de dados (ponto flutuante, ponto fixo, inteiros) e etc, possibilitando um sistema mais amigável ao projetista. / The demand for new technologies, enhanced security and comfort for urban cars has grown considerably in recent years prompting the industry to create systems designed to support drivers (ADAS - Advanced Driver Assistance Systems). This fact contributed to the development of many embedded systems in the automotive area among them, the pedestrians collision avoidance. Through the advancement in various research, began circulating through the streets vehicles with anti-collision systems and autonomous navigation. However, to achieve ever more challenging goals, designers need tools to unite technology and expertise from different areas efficiently. In this context, there is a demand for building systems that increase the level of abstraction of models of image processing for use in embedded systems enabling better design space exploration. To help minimize this problem, this research demonstrates a develop a specific framework for hardware/software codesign to build ADAS systems using computer vision. The framework aims to facilitate the development of applications, allowing better explore the design space, and thus contribute to a performance gain in the development of embedded systems in relation to building entirely in hardware. One of the requirements of the project is the possibility of the simulation of an application before synthesis on a reconfigurable system. The main challenges of this system were related to the construction of the intercommunication system between the various Intellectual Property (IP) blocks and the software components, abstracting from the end user numerous hardware details, such as memory management, interruptions, cache, types (Floating point, fixed point, integers) and so on, enabling a more user-friendly system for the designer.

This study assesses the extent to which employees and users of public services can develop collaborative partnerships that promote person-centred services within institutions. Both citizen and worker participation are currently advocated as a means to develop public services, yet academically they have been studied within distinctive disciplines. Drawing together different theories of participation alongside the analysis of the concepts and practices of co-production, co-design and co-creation, this thesis establishes an analytic framework, termed co-participation to explore processes of collaboration between public service staff and users. This framework then informs the analysis of two case studies in local government and the health service where both staff and service users are involved together in developing person-centred services. This empirical work is supplemented by expert interviews with people who have worked in a number of different collaborative projects, alongside a realist synthesis of other similar cases. Using a critical realist approach and retroductive analysis this study explores how agents act within their institutional and policy contexts, assessing the extent to which their actions can instigate changes through institutionally designed participatory projects. It is found that the projects facilitated processes of reflexivity and intersubjectivity which promoted a sense of embedded collectivism within institutional contexts. The projects enabled agents to make many localised changes which positively impacted people’s lived experiences. Collectivities and networks were developed, yet these operated within dominant hierarchies and could be limited by their structural and cultural environments. Wider social inequalities and power relations had an impact upon these participatory processes, although participatory processes could also be adapted to enable greater access and more equal voice. These projects and practices are analysed within the wider context of the continuing neo-liberal reform of public services, exploring how the state shapes the structural and policy context which sets situational logics and conditions of possibility for these practices.

Este trabalho aborda o problema de controle baseado em eventos para sistemas em tempo discreto, considerando que o sistema possui os dispositivos atuadores e sensores em nós diferentes e separados por uma rede de comunicação. A estratégia baseada em eventos consiste em reduzir a utilização da rede ao transmitir as informações do sensor para o atuador apenas quando um evento é gerado pela violação de um determinado limiar pela função de disparo. Primeiramente, são formuladas condições para a estabilidade de um sistema linear com realimentação estática de estados sob a estratégia proposta, com base na teoria de Lyapunov. Como as condições são postas na forma de desigualdades matriciais lineares (LMIs, do inglês linear matrix inequalities), problemas de otimização convexos podem ser utilizados na determinação dos parâmetros da função de disparo, bem como na resolução do problema de co-design, ou seja, do projeto simultâneo do controlador e da função de disparo, os quais são providos na sequência. A partir deste resultado básico, a metodologia é estendida para o caso em que ocorre a saturação do atuador. A seguir, é apresentada a extensão da metodologia para o caso em que o estado da planta não está disponível para o sensor, sendo então utlizado um observador de estados, considerando-se tanto o caso em que o modelo da planta utilizado no observador corresponde exatamente à dinâmica real da planta quanto o caso em que este modelo apresenta incertezas. Exemplos numéricos são apresentados para ilustrar todas as classes de sistemas consideradas, com os quais constata-se que a estratégia proposta é eficiente na redução da utilização dos recursos da rede de comunicação. / This work approaches the problem of event-triggered control for discrete time systems, considering that the system has the actuator and sensor devices in different nodes, separated by a communication network. The event-triggered strategy consists in reducing the utilization of the network by only transmitting the information from the sensor to the actuator when an event is generated by the violation of a determined threshold by the trigger function. Firstly, conditions for the stability of a linear system with a static state feedback under the proposed strategy are formulated based on the Lyapunov theory. Since the conditions are given in the form of linear matrix inequalities (LMIs), convex optimization problems can be used for the determination of the trigger function parameters, as well as the co-design of the feedback gain and the trigger function, which are given next. From this basic result, the methodology is extended to the case where occurs the saturation of the actuator. Following, the extension of the methodlogy to the case in which the plant states are not available for measure is presented, and a state-observer is used, considering both the case that the plant model corresponds exactly to the real plant dynamics and the case where this model has uncertainties. Numeric examples are shown to illustrate all the system classes considered, with which it is found that the proposed strategy is efficient in the reduction of the network resources utilization.

Denna studie syftade till att ta fram ett ramverk för utveckling av API:er för tjänsteorienteradearkitekturer. Studien tar sin utgångspunkt i forskningsprojektet e-Me (utvecklingenav en integrationsplattform för att underlätta studenters vardag) samt en benchmarking avde i nuläget mest använda API:erna på webben. Studien har fem faser: En litteraturstudie,en benchmarking, en kvalitativ genererande intervjustudie, en teoribildande fas (framtagningav ramverket), samt en kvalitativ validerande studie. Litteraturstudien tar upp sådanafenomen som utvecklingsmetoder, systemarkitekturer (bland annat SOA) samt metautveckling.Denna studie låg till grund för den första intervjustudien, som i sin tur låg tillgrund för benchmarkingen. Resultatet av dessa två studier bildade tillsammans en grundför ramverket SOAPIF (Service-Oriented Application Programming Interface Framework),som till en början innehöll fyra olika faser: Conceptualization, där man försökerbilda sig en uppfattning om vad API:et skall exponera; Definition, där man försöker definieraett kontrakt för API:et; Testing & Implementation som tar sin utgångspunkt i testerför att implementera API:et; samt Delivery, som är den fas där API:et skall levereras. Ialla dessa faser ingick kontinuerligt dokumentation samt co-design. Efter en validering avramverket byttes de fyra faserna ut mot fem arbetsmoment, med samma namn som fasernaovan, med ett tillägg: Ett arbetsmoment som heter API Evaluation, och som syftar tillatt efter leveransen tillsammans med konsumenterna av API:et utvärdera det. Utifrån deresultat som denna studie genererat, har följande slutsatser kunnat dras: Det är oerhörtviktigt med flexibla API:er som utvecklas i samarbete med den tänkta slutkonsumenten,och att dessa API:er testas mot de förväntningar som konsumenterna har på dem. Det ärockså oerhört viktigt att API:er är väldokumenterade, för att underlätta för konsumenter.När det gäller integrationsplattformar är anledningen till att man utvecklar dessa främstett behov av flexibilitet.

Co-design är en filosofi som kan tillämpas under en systemutvecklingsprocess. Grundtanken iCo-design är att man ska titta på verkligheten utifrån flera olika perspektiv för att sedan väljadet mest lämpliga perspektivet. Co-design har bara tillämpats under ettsystemutvecklingsprojekt och det är e-Me projektet som genomfördes på Högskolan i Borås.Under e-Me projekt så utgick man från användarna, som då var studenter, och tog, genomworkshops med användarna, fram storyboards och scenarier. Dessa storyboards och scenarierlåg sedan till grund för kravspecifikationen i e-Me. När utvecklarna sedan mottogkravspecifikationen så blev det problem eftersom serierna inte var tillräckligt detaljerade menockså för att utvecklarna inte varit delaktiga i utvecklingen av dem. Målet med vår studie varatt vi skulle förbättra arbetssättet att ta fram en kravspecifikation samt utformningen av den. Ivår studie har vi avgränsat oss till intressenterna användare, finansiär och utvecklare. Vi har ivår studie intervjuat de olika intressenterna för att få deras synvinklar på kravspecifikation.Utifrån deras synvinklar så har vi tagit fram förslag på metaforer som skulle passa de olikaintressentgrupperna. Vi har även tagit fram ett förslag på hur arbetssättet att ta fram enkravspecifikation skulle se ut och i den modellen har vi visat på ett förslag på hur dokumententill de olika intressenterna arbetas fram. För att få en större insikt i hur man kan arbeta somCo-designer så har vi i vår studie arbetat enligt Co-design filosofin genom att vi har tittat påalla intressenters perspektiv, tagit fram metaforer till de olika intressenterna, använt oss av ettdesignspråk samt anordnat workshops med intressenterna.

With the increasing popularity of information technologies, many companies try to set up a virtual network in order to share their business information. The purpose of creating such a virtual network is to create a new knowledge base on the combination of the existing knowledge. Collaboration is very necessary in such a virtual network as crass-unit collaboration takes place when people from different units work together in cross-unit teams on a common task or provide significant help to each other. Recently, co-design is an emerging technology in the field of informatics. It is considered as the development of system thinking, and it is a collaborative designing process which recruits designers, researchers, stakeholders and others together. The purpose of this collaborative activity is to sole designing problems. Therefore, if we want to increase collaboration in a co-design process, we need to look at a ways of increasing the efficiency of collaboration. The rapid development of accessible, reliable, and user-friendly information technology offers improvements to traditional collaboration, and makes new approaches possible. Many platforms for the exchange of information such as the Internet, email, and video-conferencing are well established aids to collaborative activities. Therefore, my research investigates to create an efficient virtual network for a co-design process. In this research, I will try to investigate that what is the need of a virtual network for co-design process and what are those virtual network soft-wares which can help us in a co-design process. My research discussion is related to the theory of CSCW (Computer Supported cooperative work). / Program: Magisterutbildning i informatik

Föreliggande studie undersöks hur personer med dyslexi upplever användbarheten i tvåav de datorbaserade hjälpmedel som finns för personer med dyslexi, Stava Rex ochWordRead Plus. Studien beskriver ämnesområden såsom dyslexi, användbarhet,interaktionsdesign, co-design och programvaruutveckling.Det finns olika sorters dyslexi vilket innebär att de svårigheter som personer med dyslexiupplever kan yttra sig på olika sätt. Därför har intervjuer med två respondenter angåendederas syn de två datorbaserade hjälpmedel som valdes för studien, Stava Rex ochWordRead Plus, utförts. Även en observation utfördes där respondenterna fick interageramed de datorbaserade hjälpmedlen och beskriva sina åsikter och tankar avseendeanvändbarheten i hjälpmedlen och hjälpmedlen i sig.Studien syftade till att besvara huvudfrågan ”Vilka designprinciper är viktiga att tillämpavid utveckling av datorbaserade hjälpmedel för personer med dyslexi?” genomdelfrågorna ”Vilken sorts datorbaserade hjälpmedel har personer med dyslexi behovav?”, ”Vilka egenskaper är viktiga hos datorbaserade hjälpmedel för personer meddyslexi?”, Hur kan god användbarhet hos datorbaserade hjälpmedel för personer meddyslexi uppnås?” samt ”Vad är användbarhet?”.Studiens slutsats var att designprinciper som berör bekvämlighet, behaglighet,tillförlitlighet och välutvecklade hjälpfunktioner är viktiga att följa då de medför en bättreprodukt med hög användbarhet och tillfredsställda användare. För att uppnå godanvändbarhet räcker det dock inte att utvecklaren endast följer designprinciperna utandessa måste kontrolleras genom att även användarna tas med i utvecklingsprocessen. / Program: Kandidatutbildning i informatik

More than 59 million children are out of schools across the globe (UNESCO Institute for Statistics and UNICEF, 2015), despite the promise of education for all children by the year 2015. The situation is more pronounced in developing countries particularly in Africa and South Asia. Strategies adopted globally to attract children towards schools rarely considered improving the existing physical environments, despite evidence that primary school aged children (five to 12 years) learn more effectively when their education is incorporated with surrounding environments (Khan & Islam, 2014; Lieberman & Hoody, 1998; Mygind, 2009). This study investigated the potential of a primary school ground to be an effective learning environment and explores how the design of an outdoor environment can contribute to children’s learning. This interdisciplinary project is underpinned by classic psychological theories of child development (e.g. Piaget, 1964 and Vygotsky et al., 1978), while Gibson’s (1979) ‘Concept of Affordance’ and Barker’s (1976) ‘Theory of Behaviour Settings’ have provided the framework for exploring the relationship between the school ground and children’s learning. A quasi-experimental action research project was carried out in a Government primary school in Bangladesh, which included the design and development of the school ground, with the direct participation of children, teachers and parents. Another primary school (with no change to the outdoor environment) was used as a control school to compare the outcomes. A mixed methods approach to conduct this quasi-experiment included data from existing exam scores, questionnaire survey, observation and behaviour-mapping, focus group discussions and in-depth interviews. The key findings from this study indicate an overall positive influence of the designed outdoor environment on children’s academic performance and their motivation to learn. An increase in children’s cognitive, social and physical activities in the school ground is also evidenced by the study. The analysis of the data likewise reveals that different behaviour settings of the school ground offered opportunities for different teaching and learning activities. Both natural settings and settings with built features afforded more focused activities (e.g. gardens afforded exploration and connection with nature, while the play area afforded more functional play). Additionally, settings comprised of both natural and built elements (e.g. the area with loose materials and huts) and areas in close proximity with natural ones (i.e. the open yard) accommodated diverse and multiple teaching and learning activities (e.g. measuring, building/constructing and exploring). The findings further suggest that the design and use of the school ground had a surprising and unintended positive effect on teachers’ motivation and pedagogy. Through reflecting on the use of different landscape elements and settings in the school ground during formal outdoor classes and informal play times, the study has further come to propose some design recommendations for other new school grounds as well as the redesign of existing ones.