With the grasp of a smart grid in sight, discussions have shifted the focus of system security measures away from generation capacity; apart from modifying the supply side, demand may also be exploited to keep the system in balance. Specifically, Demand Response (DR) is the concept of consumer load modification as a result of price signaling, generation adequacy, or state of grid reliability. Implementation of DR mechanisms is one of the solutions being investigated to improve the efficiency of electricity markets and to maintain system-wide stability.  In a liberalized electricity sector, with a smart grid vision that is committed to market-based operation, end-users have now become the focal point of decision-making at every stage of the process in producing, delivering and consuming electricity. DR program implementation falls within the smart grid domain: a complex socio-technical energy system with a multiplicity of physical, economic, political and social interactions. This thesis thus employs both qualitative and quantitative research methods in order to address the ways in which residential end-users can become active DR flexibility providers in deregulated European electricity markets. The research focuses on economic incentives including dynamic pricing contracts, dynamic distribution price signals and the aggregation of load flexibility for participation in the various short-term electricity markets. / <p>The Doctoral Degrees issued upon completion of the programme are issued by Comillas Pontifical University, Delft University of Technology and KTH Royal Institute of Technology. The invested degrees are official in Spain, the Netherlands and Sweden, respectively.</p><p>QC 20160225</p> / Erasmus Mundus Joint Doctorate in Sustainable Energy Technologies and Strategies (SETS)

This study identifies the cause of unstable vibrations that sporadically occur in decanting centrifuges as being caused by a combination of internal bearing clearance, conveyor unbalance and low bearing loads. These centrifuges are different from other rotating equipment common in industry (pumps, fans, compressors, electric motors) in that they are dual rotor systems – one rotor inside the other. Unbalance in either rotor can produce severe vibration of the whole machine when the running speed is close to a mode of vibration – that is, running at or near a critical speed. The external rotor, called the bowl, is subjected to an internal pressure generated by the centrifugal force of the product being separated. The internal rotor is supported from the bowl and is in the form of an auger screw. The main supporting bearings are subjected to forces from both the bowl and the auger - the liquid end bearing also supports the gearbox. Being able to predict critical speeds through numerical or computational analysis is a necessary step in the design process or for troubleshooting vibration problems. As part of the study, the main rolling element bearings were replaced by oil-film journal bearings to assess the viability of their use. Journal bearings are simpler, of lower cost and generate less noise than their rolling element counterparts. However, instability in running above the first critical speed can result due to oil film forces and internal hysteresis of the rotor assembly. The auger is asymmetric so instability in running is possible at around half the first critical speed. This study was undertaken to understand the dynamics of decanting type centrifuges and develop a methodology for identifying their critical speeds and cause of unstable vibration. In the longer term this will assist in the generation of new designs that are quieter, use less energy and have better separation efficiencies.

The Department of Applied Physics and Electronics at Umeå University offers education and conducts research in the field of automation and robotics. To raise the competence in automation in the CODESYS development environment it’s proposed to build a remote controlled self-balancing robot as a testing platform which is then programmed using CODESYS for Raspberry Pi.   The chassis of the robot consists of laser-cut plexiglass plates, stacked on top of each other and fixed using threaded rods, nuts and washers. On these plates the robots’ electrical components, wheels and motors are attached.   The control system is designed as a feedback loop where the robots’ angle relative to the gravity vector is the controlled variable. A PID-controller is used as the system controller and a Kalman Filter is used to filter the input signals from the IMU board using input from both the accelerometer and the gyro.   The control system is implemented in CODESYS as a Function Block Diagram (FBD) using both pre-made, standard function blocks and customized function blocks. By using the in-built web-visualization tool the robot can be remote controlled via Wi-Fi.   After tuning the Kalman Filter through plot-analysis and the PID-controller through Ziegler-Nichols method the robot can stay balanced on a flat surface.   The robots’ performance is tested through a series of test scenarios of which it only completes one out of four. The project ran out of time before further testing could be done.   For future work one could improve the performance of the PID-controller through more sophisticated tuning methods. One can also add a steering-function or test different type of controllers.

Parasitism is one of the most common ways of living and it has arised in many taxa. Parasites feed and live inside or on their hosts resulting in both long and short term consequences for the host. This thesis is exploring the phenotypic and genotypic effects of animals living with parasitic infections. I have been studying three different parasite groups and their associated host species: the great snipe, a lekking freshwater wader bird that migrates between Africa and Northern Europe; the tree sparrow, a stationary passerine found close to human settlements and lastly the water vole, a large rodent living in riparian habitats. Avian malaria is one of the most commonly studied parasites affecting birds. Atoxoplasma, an intestinal protozoan parasite is less studied but is thought to be endemic in free-ranging birds. Given the freshwater habitat great snipes inhabit, a prevalence of 30% avian malaria infections is not high and that the prevalence fluctuated among years. Sequencing of the avian malaria cytochrome b gene revealed that parasites are similar to avian malaria parasites found in African birds suggesting that they were infected on the wintering grounds in Africa. Tree sparrows had few malaria infected individuals, a result that is consistent with other studies of stationary birds at high latitudes. Atoxoplasma infections were common in tree sparrows and capture-recapture analyses show decreased survival in infected compared to uninfected birds and signs of lower mating success among infected. Genetic analyses comparing the transcriptome between mated and unmated great snipe males revealed that the genotype is important for mating success and health status for some of the expressed genes. That variations in some of these genes are involved in maintaining a good health status and mating success supports handicap models for sexual selection in this lek mating system. The major histocompatibility complex (MHC) is a part of the immune system and it contains genes involved in immune response. In water voles, a number of new MHC alleles were identified. Based on their in silico phenotype they were grouped into supertypes to facilitate studies on how helminth infections affect the MHC diversity in the water voles. Some of these MHC supertypes provided resistance to one helminth species, but the same supertype caused the opposite effect for other helminth parasites. Overall, parasites are a driving force for maintaining genetic diversity and parasite infections lowers survival rate, which would lead to a lower lifetime breeding success.

Heterogeneous wireless networking technologies such as satellite, UMTS, WiMax and WLAN are being used to provide network access for both voice and data services. In big cities, the densely populated areas like town centres, shopping centres and train stations may have coverage of multiple wireless networks. Traditional Radio Access Technology (RAT) selection algorithms are mainly based on the 'Always Best Connected' paradigm whereby the mobile nodes are always directed towards the available network which has the strongest and fastest link. Hence a large number of mobile users may be connected to the more common UMTS while the other networks like WiMax and WLAN would be underutilised, thereby creating an unbalanced load across these different wireless networks. This high variation among the load across different co-located networks may cause congestion on overloaded network leading to high call blocking and call dropping probabilities. This can be alleviated by moving mobile users from heavily loaded networks to least loaded networks. This thesis presents a novel framework for load balancing in heterogeneous wireless networks incorporating the IEEE 802.21 Media Independent Handover (MIH). The framework comprises of novel load-aware RAT selection techniques and novel network load balancing mechanism. Three new different load balancing algorithms i.e. baseline, fuzzy and neural-fuzzy algorithms have also been presented in this thesis that are used by the framework for efficient load balancing across the different co-located wireless networks. A simulation model developed in NS2 validates the performance of the proposed load balancing framework. Different attributes like load distribution in all wireless networks, handover latencies, packet drops, throughput at mobile nodes and network utilization have been observed to evaluate the effects of load balancing using different scenarios. The simulation results indicate that with load balancing the performance efficiency improves as the overloaded situation is avoided by load balancing.

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Faculty of Humanities School of Arts 0317536k b_balancing_act@yahoo.com / After endless contemplation on the idea of ‘word and image’, the following expression of J.W.T Mitchell in Word and Image (1996: 56) brought insight: ‘[W]ord and image’… a pair of terms whose relations open a space of intellectual struggle, historical investigation, and artistic/critical practice. Our only choice is to explore this space (own emphasis). I shifted my position from the forlorn act of peeling to one of creative exploration. Not necessarily exploring the specific space between word and image, but rummaging ‘the space between’; always hovering amid opposites. This space provides an opportunity to confront and debate the many issues that stem from the relations formed in its fluidity. It is a space that informs my thinking. It is a space of conversation. I see not only my writing, but also the art that I scrutinize as conversation. My conversation is captured in the linear structure of this thesis, but the conversation of art is dynamic. It is informal and flexible – following not one path, offering no answer, giving the potential at each moment for surprises and transformation. The idea is to ponder contemporary art’s dialogue, the manipulators thereof and the indispensable factors constituting this notion: space, grammar, medium, criticism. The notion of dialogue assumes a listener, a participant, an audience. But who is this audience with whom ideas are conversed, and what language do you (presumably) use to communicate the necessary? I have chosen to investigate these questions, the purpose and plan of art, with relation to a selected group of artists: an individual, Terry Kurgan and a collective – Stephen Hobbs, Marcus Neustetter and Kathryn Smith, known as The Trinity Session.

O objeto de estudo da presente dissertação corresponde ao sopesamento ou ponderação, método que vem sendo aplicado de modo freqüente em vários países para a resolução de colisões entre direitos fundamentais. Por ser altamente difundido atualmente, muitas vezes o cenário é caracterizado por uma aplicação irrefletida, ou seja, sem maiores questionamentos sobre o método em si. No entanto, existe grande discussão sobre o tema, principalmente sobre se é possível aplicar o sopesamento de forma racional. Neste trabalho, o foco da pesquisa constitui exatamente analisar detalhadamente os problemas de aplicação do método, relacionados à possibilidade do desenvolvimento de critérios racionais de decidibilidade. Em outras palavras, procura-se examinar se é possível considerar o sopesamento um método racional na decisão de colisões entre direitos fundamentais, no intuito de se investigar as possibilidades de fundamentação dos juízos ponderativos, assim como as pretensões de racionalidade, correção ou objetividade que se podem relacionar à técnica. Para isso, a pesquisa examinou o debate teórico sobre sopesamento e, tendo em mente as críticas analisadas, foi realizada análise sobre o conceito de racionalidade possível no direito e sobre a estrutura e modelos de ponderação. / The purpose of this paper is to analyze balancing or weighing rights, method that is frequently used worldwide in judicial decisions when principles collide. As its central position in the argumentation of many judicial decisions, the method is often used without a special reflection on its meaning and structure. Notwithstanding, there is a debate about the theme, mainly about if it is possible to use balancing rationally. In this paper, the focus is to analyze the problems related to the method and to the possibility of developing rational criteria. In other words, I seek to examine whether it is possible to consider balancing as a rational method in judicial decisions involving collisions between fundamental rights, in order to investigate the possibilities of reasoning, as well as the claims of rationality, objectivity, or the structure that may relate to the procedure. For this, the research examined the theoretical debate on weighing rights and, after that, studied the concept of rationality possible in law and the structure of weighting models.

We have built an application that integrates a technical editor feature and a custom real-time strategy game. The end users are able to use the technical editor feature for tweaking and customizing the unit attributes and progressions in the game using simple mathematical formulas, and they can play or test their tweaked formulas within the game. Various game modes in the software, which are Single Player, Multiplayer, and Simulation, can help display to the end users the results of their tweaked formulas, or users can just have fun by playing the game. The software was evaluated to see whether the software with the editor feature enabled is more attractive and appealing to the end users than the software with the editor feature disabled. The evaluation is based on the players’ feedback on the game with or without the editor. A total of 50 testers were randomly assigned into 2 groups evenly, the Tool group and the Game group. Testers assigned to the Tool group were able to customize the game unit attributes via the editor and play, while the testers in the Game group only play the game. The results from the post-test survey show both versions of the software are highly appealing to the testers, and there is no significant difference in game appeals between the Tool version and the Game version.

Os atuais sistemas de HPC tem realizado simulações mais complexas possíveis, produzindo benefícios para diversas áreas de pesquisa. Para atender à crescente demanda de processamento dessas simulações, novos equipamentos estão sendo projetados, visando à escala exaflops. Um grande desafio para a construção destes sistemas é a potência que eles vão demandar, onde perspectivas atuais alcançam GigaWatts. Para resolver este problema, esta tese apresenta uma abordagem para aumentar a eficiência energética usando recursos de HPC, objetivando reduzir os efeitos do desequilíbrio de carga e economizar energia. Nós desenvolvemos uma estratégia baseada no consumo de energia, chamada ENERGYLB, que considera características da plataforma, irregularidade e dinamicidade de carga das aplicações para melhorar a eficiência energética. Nossa estratégia leva em conta carga computacional atual e a frequência de clock dos cores, para decidir entre chamar uma estratégia de balanceamento de carga que reduz o desequilíbrio de carga migrando tarefas, ou usar técnicas de DVFS par ajustar as frequências de clock dos cores de acordo com suas cargas computacionais ponderadas. Como as diferentes arquiteturas de processador podem apresentam dois níveis de granularidade de DVFS, DVFS-por-chip ou DVFS-por-core, nós criamos dois diferentes algoritmos para a nossa estratégia. O primeiro, FG-ENERGYLB, permite um controle fino da frequência dos cores em sistemas que possuem algumas dezenas de cores e implementam DVFS-por-core. Por outro lado, CG-ENERGYLB é adequado para plataformas de HPC composto de vários processadores multicore que não permitem tal refinado controle, ou seja, que só executam DVFS-por-chip. Ambas as abordagens exploram desbalanceamentos residuais em aplicações interativas e combinam balanceamento de carga dinâmico com técnicas de DVFS. Assim, eles reduzem a frequência de clock dos cores com menor carga computacional os quais apresentam algum desequilíbrio residual mesmo após as tarefas serem remapeadas. Nós avaliamos a aplicabilidade das nossas abordagens utilizando o ambiente de programação paralela CHARM++ sobre benchmarks e aplicações reais. Resultados experimentais presentaram melhorias no consumo de energia e na demanda potência sobre algoritmos do estado-da-arte. A economia de energia com ENERGYLB usado sozinho foi de até 25% com nosso algoritmo FG-ENERGYLB, e de até 27% com nosso algoritmo CG-ENERGYLB. No entanto, os desequilíbrios residuais ainda estavam presentes após as serem tarefas remapeadas. Neste caso, quando as nossas abordagens foram empregadas em conjunto com outros balanceadores de carga, uma melhoria na economia de energia de até 56% é obtida com FG-ENERGYLB e de até 36% com CG-ENERGYLB. Estas economias foram obtidas através da exploração do desbalanceamento residual em aplicações interativas. Combinando balanceamento de carga dinâmico com DVFS nossa estratégia é capaz de reduzir a demanda de potência média dos sistemas paralelos, reduzir a migração de tarefas entre os recursos disponíveis, e manter o custo de balanceamento de carga baixo. / Current HPC systems have made more complex simulations feasible, yielding benefits to several research areas. To meet the increasing processing demands of these simulations, new equipment is being designed, aiming at the exaflops scale. A major challenge for building these systems is the power that they will require, which current perspectives reach the GigaWatts. To address this problem, this thesis presents an approach to increase the energy efficiency using of HPC resources, aiming to reduce the effects of load imbalance to save energy. We developed an energy-aware strategy, called ENERGYLB, which considers platform characteristics, and the load irregularity and dynamicity of the applications to improve the energy efficiency. Our strategy takes into account the current computational load and clock frequency, to decide whether to call a load balancing strategy that reduces load imbalance by migrating tasks, or use Dynamic Voltage and Frequency Scaling (DVFS) technique to adjust the clock frequencies of the cores according to their weighted loads. As different processor architectures can feature two levels of DVFS granularity, per-chip DVFS or per-core DVFS, we created two different algorithms for our strategy. The first one, FG-ENERGYLB, allows a fine control of the clock frequency of cores in systems that have few tens of cores and feature per-core DVFS control. On the other hand, CGENERGYLB is suitable for HPC platforms composed of several multicore processors that do not allow such a fine-grained control, i.e., that only perform per-chip DVFS. Both approaches exploit residual imbalances on iterative applications and combine dynamic load balancing with DVFS techniques. Thus, they reduce the clock frequency of underloaded computing cores, which experience some residual imbalance even after tasks are remapped. We evaluate the applicability of our approaches using the CHARM++ parallel programming system over benchmarks and real world applications. Experimental results present improvements in energy consumption and power demand over state-of-the-art algorithms. The energy savings with ENERGYLB used alone were up to 25%with our FG-ENERGYLB algorithm, and up to 27%with our CG-ENERGYLB algorithm. Nevertheless, residual imbalances were still present after tasks were remapped. In this case, when our approaches were employed together with these load balancers, an improvement in energy savings of up to 56% is achieved with FG-ENERGYLB and up to 36% with CG-ENERGYLB. These savings were obtained by exploiting residual imbalances on iterative applications. By combining dynamic load balancing with the DVFS technique, our approach is able to reduce the average power demand of parallel systems, reduce the task migration among the available resources, and keep load balancing overheads low.