De multiples questions se posent sur les liens sociaux. Parmi elles, le présent travail s'intéresse plus spécifiquement à leur orchestration à l'échelle individuelle : comment s'agencent ou sont agencés les liens sociaux qu'entretient au quotidien un individu ? En tant que reflets de ces liens, les mobilités tant réelles (déplacements) que virtuelles (pratiques des Technologies de l'Information et de la Communication) permettent de mettre en évidence les façons dont les liens privés et professionnels s'articulent, se positionnent les uns par rapport aux autres, entre superposition et séparation. Outre l'idéal hypermoderne du fluide ou superposition totale, d'autres topologies aux degrés moindres d'ouverture existent : la région et le réseau. L'existence de ces trois figures topologiques montre que l'agencement des sphères et des liens sociaux vues à travers les pratiques de mobilités est une activité complexe. Cette activité est le produit même des liens sociaux individuels. Ces derniers jouent dans leur dimension verticale (les normes) et dans leur dimension horizontale (les relations interpersonnelles). Toutefois, en tant qu'élément central de ces liens, l'individu joue un rôle important dans le travail d'orchestration de son quotidien.

Distributed generation (DG) with a converter interface to the power grid is found in many of the green power resources applications. This dissertation describes a multi-objective control technique of voltage source converter (VSC) based on multilevel converter topologies, for integration of DG resources based on renewable energy (and non-renewable energy)to the power grid. The aims have been set to maintain a stable operation of the power grid, in case of di erent types of grid-connected loads. The proposed method provides compensation for active, reactive, and harmonic load current components. A proportional-integral (PI) control law is derived through linearization of the inherently non-linear DG system model, so that the tasks of current control dynamics and dc capacitor voltage dynamics become decoupled. This decoupling allows us to control the DG output currents and the dc bus voltage independently of each other, thereby providing either one of these decoupled subsystems a dynamic response that signi cantly slower than that of the other. To overcome the drawbacks of the conventional method, a computational control delay compensation method, which delaylessly and accurately generates the DG reference currents, is proposed. The rst step is to extract the DG reference currents from the sensed load currents by applying the stationary reference frame and then transferred into synchronous reference frame method, and then, the reference currents are modi ed, so that the delay will be compensated. The transformed variables are used in control of the multilevel voltage source converter as the heart of the interfacing system between DG resources and power grid. By setting appropriate compensation current references from the sensed load currents in control circuit loop of DG link, the active, reactive, and harmonic load current components will be compensated with fast dynamic response, thereby achieving sinusoidal grid currents in phase with load voltages while required power of loads is more than the maximum injected power of the DG resources. The converter, which is controlled by the described control strategy, guarantees maximum injection of active power to the grid continuously, unity displacement power factor of power grid, and reduced harmonic load currents in the common coupling point. In addition, high current overshoot does not exist during connection of DG link to the power grid, and the proposed integration strategy is insensitive to grid overload. / La Generació Distribuïda (DG) injectada a la xarxa amb un convertidor estàtic és una solució molt freqüent en l'ús de molts dels recursos renovables. Aquesta tesis descriu una técnica de control multi-objectiu del convertidor en font de tensió (VSC), basat en les topologies de convertidor multinivell, per a la integració de les fonts distribuïdes basades en energies renovables i també de no renovables.Els objectius fixats van encaminats a mantenir un funcionament estable de la xarxa elèctrica en el cas de la connexió de diferents tipus de càrregues. El mètode de control proposat ofereix la possibilitat de compensació de les components actives i reactives de la potencia, i les components harmòniques del corrent consumit per les càrregues.La llei de control proporcional-Integral (PI) s’obté de la linearització del model inherentment no lineal del sistema, de forma que el problema de control del corrent injectat i de la tensió d’entrada del convertidor queden desacoblats. Aquest desacoblament permet el control dels corrents de sortida i la tensió del bus de forma independent, però amb un d’ells amb una dinàmica inferior.Per superar els inconvenients del mètode convencional, s’usa un retard computacional, que genera les senyals de referència de forma acurada i sense retard. El primer pas es calcular els corrents de referència a partir de les mesures de corrent. Aquest càlcul es fa primer transformant les mesures a la referència estacionaria per després transformar aquests valors a la referència síncrona. En aquest punt es on es poden compensar els retards.Les variables transformades son usades en els llaços de control del convertidor multinivell. Mitjançant aquests llaços de control i les referències adequades, el convertidor és capaç de compensar la potencia activa, reactiva i els corrents harmònics de la càrrega amb una elevada resposta dinàmica, obtenint uns corrents de la xarxa de forma completament sinusoïdal, i en fase amb les tensions.El convertidor, controlat amb el mètode descrit, garanteix la màxima injecció de la potencia activa, la injecció de la potencia reactiva per compensar el factor de potencia de la càrrega, i la reducció de les components harmòniques dels corrents consumits per la càrrega. A més, garanteix una connexió suau entre la font d’energia i la xarxa. El sistema proposat es insensible en front de la sobrecarrega de la xarxa

Supersymmetry (SUSY) is the most motivated scenario beyond the Standard Model (SM) addressing the problems of the SM in an elegant way by establishing a symmetry which relates matter particles to interaction particles and vice versa. The simplest phenomenologically viable supersymmetric theory is the Minimal Supersymmetric Standard Model (MSSM) which can be accommodated to minimal Supergravity (mSuGra) theory in order to both take gravity into account and constrain its parameter space. CMS detector is one of the general purpose detectors constructed at LHC (Large Hadron Collider) which targets to search for SUSY signal. This thesis presents a search strategy for SUSY in three different fully hadronic jet topologies with the CMS detector. Di-jet, 3-jet, and 4-jet event topologies offer clear signatures for SUSY searches and the key SUSY decay modes of these jet topologies appear to be squark pair production, squark-gluino production, and gluino pair production, respectively. In these jet topologies, an important kinematical variable named alpha, &amp / #945 / is used to separate SUSY signal test points from the SM background events including QCD, EWK (Electroweak), and invisible decay of Z boson processes. Alpha variables are found to be very useful in terms of enhancing SUSY signal while rejecting all QCD events. Discriminating power of alpha variables are shown in terms of signal-to-background and signal significance calculations and the results are found to be promising which further encourage searches for SUSY signal in jet event topologies with the early CMS data at 1 f b^{&amp / #8722 / 1} integrated luminosity.

The Message Passing Interface (MPI) standard defines virtual topologies that can be applied to systems of cooperating processes. Among issues regarding a more convenient namespace this may be used to optimize the placement of MPI processes in order to reduce communication time. That means, the processes with their main communication paths represent a graph that has to be cost efficiently mapped onto the graph representing the actual communication network. In this context, this work analyses and compares state-of-the-art task mapping strategies with respect to running time and their quality of solutions to the MPI mapping problem. In particular, the focus is on generic strategies that can be used for arbitrary process/network topologies although, here, the topologies of interest are regular ones, where the number of processes is greater than the number of processors in the underlying physical network. Additionally, different measures of mapping quality are discussed and a close correspondence between the most appropriate, the weighted edge cut, and program execution time is shown. In order to investigate how mapping quality affects MPI program execution time, some mapping strategies have been incorporated into Open MPI. Finally, benchmark results prove that optimized process-to-processor mappings can improve program execution time by up to 60%, compared to the default mapping in many MPI implementations (linear mapping). The findings in this work can serve as reference not only for MPI implementors, but also for researchers investigating static process-to-processor mappings, in general.

While evolutionary computation is well suited for automatic discovery in engineering, it can also be used to gain insight into how humans and organizations could perform more effectively. Using a real-world problem of innovation search in organizations as the motivating example, this dissertation formalizes human creative problem solving as competitive multi-agent search. It differs from existing single-agent and team-search problems in that the agents interact through knowledge of other agents' searches and through the dynamic changes in the search landscape caused by these searches. The main hypothesis is that evolutionary computation can be used to discover effective strategies for competitive multi-agent search. This hypothesis is verified in experiments using an abstract domain based on the NK model, i.e. partially correlated and tunably rugged fitness landscapes, and a concrete domain in the form of a social innovation game. In both domains, different specialized strategies are evolved for each different competitive environment, and also strategies that generalize across environments. Strategies evolved in the abstract domain are more effective and more complex than hand-designed strategies and one based on traditional tree search. Using a novel spherical visualization of the fitness landscapes of the abstract domain, insight is gained about how successful strategies work, e.g. by tracking positive changes in the landscape. In the concrete game domain, human players were modeled using backpropagation, and used as opponents to create environments for evolution. Evolved strategies scored significantly higher than the human models by using a different proportion of actions, providing insights into how performance could be improved in social innovation domains. The work thus provides a possible framework for studying various human creative activities as competitive multi-agent search in the future. / text

Topological maps are light-weight, graphical representations of environments that are scalable and amenable to symbolic manipulation. Thus, they are well- suited for basic robot navigation applications, and also provide a representational basis for the procedural and semantic information needed for higher-level robotic tasks. However, their widespread use has been impeded in part by the lack of reliable, general purpose algorithms for their construction. In this dissertation, I present a probabilistic framework for the construction of topological maps that addresses topological ambiguity, is failure-aware, computa- tionally efficient, and can incorporate information from various sensing modalities. The framework addresses the two major problems of topological mapping, namely topological ambiguity and landmark detection. The underlying idea behind overcoming topological ambiguity is that the com- putation of the Bayesian posterior distribution over the space of topologies is an effective means of quantifying this ambiguity, caused due to perceptual aliasing and environment variability. Since the space of topologies is combinatorial, the posterior on it cannot be computed exactly. Instead, I introduce the concept of Probabilistic Topological Maps (PTMs), a sample-based representation that ap- proximates the posterior distribution over topologies given the available sensor measurements. Sampling algorithms for the efficient computation of PTMs are described. The PTM framework can be used with a wide variety of landmark detection schemes under mild assumptions. As part of the evaluation, I describe a novel landmark detection technique that makes use of the notion of "surprise" in mea- surements that the robot obtains, the underlying assumption being that landmarks are places in the environment that generate surprising measurements. The com- putation of surprise in a Bayesian framework is described and applied to various sensing modalities for the computation of PTMs. The PTM framework is the first instance of a probabilistic technique for topo- logical mapping that is systematic and comprehensive. It is especially relevant for future robotic applications which will need a sparse representation capable of accomodating higher level semantic knowledge. Results from experiments in real environments demonstrate that the framework can accomodate diverse sensors such as camera rigs and laser scanners in addition to odometry. Finally, results are pre- sented using various landmark detection schemes besides the surprise-based one.

abstract: Utility scale solar energy is generated by photovoltaic (PV) cell arrays, which are often deployed in remote areas. A PV array monitoring system is considered where smart sensors are attached to the PV modules and transmit data to a monitoring station through wireless links. These smart monitoring devices may be used for fault detection and management of connection topologies. In this thesis, a compact hardware simulator of the smart PV array monitoring system is described. The voltage, current, irradiance, and temperature of each PV module are monitored and the status of each panel along with all data is transmitted to a mobile device. LabVIEW and Arduino board programs have been developed to display and visualize the monitoring data from all sensors. All data is saved on servers and mobile devices and desktops can easily access analytics from anywhere. Various PV array conditions including shading, faults, and loading are simulated and demonstrated. Additionally, Electrical mismatch between modules in a PV array due to partial shading causes energy losses beyond the shaded module, as unshaded modules are forced to operate away from their maximum power point in order to compensate for the shading. An irradiance estimation algorithm is presented for use in a mismatch mitigation system. Irradiance is estimated using measurements of module voltage, current, and back surface temperature. These estimates may be used to optimize an array’s electrical configuration and reduce the mismatch losses caused by partial shading. Propagation of error in the estimation is examined; it is found that accuracy is sufficient for use in the proposed mismatch mitigation application. / Dissertation/Thesis / Masters Thesis Electrical Engineering 2016

Seja (X; t) um espaço topológico e seja F a família de todos os subconjuntos de X que satisfazem uma propriedade topológica dada P (invariante por homeomorfismos). Se acrescentarmos abertos novos à topologia e se F\' é a família de todos os subconjuntos do novo espaço que satisfazem a propriedade P, podemos ter que F ≠ F\'. Se isto sempre acontece, dizemos que o espaço (X; t) é maximal com respeito à família F. Neste trabalho estudaremos os espaços topológicos maximais com respeito a algumas famílias de subconjuntos: discretos, compactos, densos, conexos e das sequências convergentes. / Let (X; t) be a topological space and let F be the family of all subsets of X that satisfy a given topological property P (invariant under homeomorphisms). If we add new open sets to the topology and if F\' is the family of all subsets of the new space which satisfy the property P, we can have F ≠ F\'. If this is always the case, we say that (X; t) is maximal with respect to the family F. We show here some characterizations of maximal spaces with respect to the family of some of its subsets: compacts, dense, discrete and convergent sequences.

The purpose of this thesis is to develop techniques for analysing interacting particle systems on the half-line. When the number of particles becomes large, stochastic partial differential equations (SPDEs) with Dirichlet boundary conditions will be the natural objects for describing the dynamics of the population's empirical measure. As a source of motivation, we consider systems that arise naturally as models for the pricing of portfolio credit derivatives, although similar applications are found in mathematical neuroscience, stochastic filtering and mean-field games. We will focus on a stochastic McKean--Vlasov system in which a collection of Brownian motions interact through a correlation which is a function of the proportion of particles that have been absorbed at level zero. We prove a law of large numbers where the limiting object is the unique solution to (the weak formulation of) the loss-dependent SPDE: dV_t(x) = 1/2 &part;_xxV_t(x)dt - p(L_t)&part;_xV_t(x)dW_t, V_t(0)=0, where L_t = 1-&lmoust;^&infin;<sub style='position: relative; left: -.8em;'>t</sub></sup>V_t(x)dx, V is a density process on the half-line and W is a Brownian motion. The correlation function is assumed to be piecewise Lipschitz, which encompasses a natural class of credit models. The first of our theoretical developments is to introduce the kernel smoothing method in the dual of the first Sobolev space, H^-1, with the aim of proving uniqueness results for SPDEs. A benefit of this approach is that only first order moment estimates of solutions are required, and in the particle setting this translates into studying the particles at an individual level rather than as a correlated collection. The second idea is to extend Skorokhod's M₁ topology to the space of processes that take values in the tempered distributions. The benefit we gain is that monotone functions have zero modulus of continuity under this topology, so the loss process, L, is easy to control. As a final example, we consider the fluctuations in the convergence of a basic particle system with constant correlation. This gives rise to a central limit theorem, for which the limiting object is a solution to an SPDE with random transport and an additive idiosyncratic driver acting on the first derivative terms. Conditional on the systemic random variables, this driver is a space-time white noise with intensity controlled by the empirical measure of the underlying system. The SPDE has insufficient regularity for us to work in any Sobolev space higher than H^-1, hence we have an example of where our extension to the kernel smoothing method is necessary.

L'énergie photovoltaïque est à nos jours l'une des sources intermittentes les plus développée. Plusieurs années de recherche confèrent une importante maturité à la fois aux modules et aux systèmes de extraction et traitement de son électricité. Cependant, il lui reste encore un important obstacle à franchir avant son utilisation à large échelle : la présence des ombres. Alors que plusieurs solutions ont été déjà proposées pour ce problème, la recherche sur l'ombre en tel que phénomène complexe reste embryonnaire. Cette thèse a pour but de combler ce besoin à la fois en étudiant la présence d l'ombre et en y proposant une nouvelle réponse. L'étude de l'ombre comprend la proposition d'une théorie sur l'intermittence qui prend en compte des aspect à la fois électriques et optiques. A travers de cette théorie, une relecture de la littérature est aussi proposée et donne lieu à une classification des solutions existantes en séries ou parallèles. Les solutions séries utilisent plusieurs structures d'électronique de puissance pour extraire l'énergie d'un nombre plus restreint des cellules photovoltaïques et par conséquent y confinent l'impact de l'ombre. En contre partie, les solutions parallèles utilisent des structures spéciales pour redistribuer le courant parmi les cellules ombrées et illuminées, ce qui amène à l'effacement de l'ombre. La nouvelle réponse à l'ombre proposée dans ce travail s'agit d'une structure parallèle à forte potentiel d'intégration monolithique. Inspirée de son équivalent pour les batteries, cette nouvelle topologie est applicable à plusieurs échelles mais sa commande reste un aspect à maîtriser. Son concept de base est validé au niveau d'un seul module photovoltaïque par la création d'un prototype et une validation expérimentale. Sa commande y est ensuite développée, testée et validée. Le système est capable de détecter la présence de l'ombre, choisir la meilleure stratégie pour la mitiger et l'implémenter en toute autonomie. Le résultat final est une augmentation de la puissance de sortie d'environ 40% dans certains cas. / Photovoltaic energy rates among the most mature renewable sources currently available in the market. However, its growing use in urban environment has met with an important obstacle: shadows. Their study present a two-fold challenge: understanding what they are and how they can be mitigated. While many authors have proposed different solutions for this problem, very few have tried to understand the shadow in its complexity. This thesis seeks, at the same time, a comprehensive view on the shadow itself while proposing a new solution to mitigate it. The comprehensive view of the shadow is proposed through an intermittency theory, where its optical properties and electrical consequences are taken into account. This theory provides the elements to review the current literature into a new perspective. The available solutions are, then, divided into two families: series and parallel. Series solutions employ several structures, each extracting the power of a reduced number of photovoltaic cells. As a consequence the impact of the shadow is restricted. Parallel solutions use few structures to redistribute the current between shaded and unshaded photovoltaic cells, thus sharing the impact of the shadow. The new solution proposed to mitigate the shadow is a parallel system called PV Equalizer. Inspired from its battery equivalent, it has a different topology with a high integration potential, easily scalable but seemingly difficult to control. To prove its concept, a study is conducted to determine its functions. It is found to be capable of not only mitigating but also detecting the shadow. These functions are characterized and their results used to conceive a control algorithm. Finally, this algorithm is tested and validated in a prototype under real operating conditions. The system detected the presence of the shadow, chose the best way to mitigate it and raised the power output by roughly 40 %.