his thesis describes Perceptual Audio Coding of MPEG1 Layer 3 format (ISO/IEC 11172-3), principles and algorithms of psychoacoustic model. MATLAB application for modeling of Psychoacoustic model 2 of this audio format is developed.

This dissertation thesis is focused to interference investigation in UMTS network and interference influence to error ratio and signal to noise or interference ratio. There are presented models based on UMTS physical layer specifications that simulate signal transmission and processing. The aim of simulations is to analyze different types of interference and to appoint the possibilities of this interference decrease.

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This thesis highlights generic aspects of contact angle hysteresis and stick-slip motion,encountered in most practical wetting situations.First, we study the scaling relation between the heterogeneity strength and the amplitudeof the contact angle hysteresis it induces in the model configuration of a chemicallyheterogeneous microchannel. A key parameter which determines the qualitativefeatures is the heterogeneity wavelength. In particular, we identify a near-thresholdbehavior where the quadratic scaling between the heterogeneity amplitude and the resultinghysteresis, already known for a dilute system of wetting defects, is explainedby the closeness to the threshold, and a macroscopic limit without observable stick-slipwhere this scaling is linear.In the second part, we adapt the description to the configuration of a meniscusaround a wavy fibre. This adaptation brings the generic results of the first part in thereach of experiments. A comparison with experiments is achieved at the level of theindividual topography-induced jumps.In the third part, we expand the formulation to treat the quasi-steady interface shapecontact line dynamics and study how the the presence of stick-slip motion at the observableor unobservable scale modifies the scaling relation between the contact linevelocity and contact angle. We recover the known result that the scaling exponent dependson the nature of the externally controlled parameter, identify the causes of thisdependency in the corresponding static limits, and predict the disappearance of this dependencyabove a critical velocity which decreases with the heterogeneity wavelength.Finally, we show trough examples how the modelling framework which permitscapturing contact angle hysteresis and stick-slip motion in a minimalistic way can beadopted to treat configurations with a finite amount of contact points, or the 3D problemof a drop with a deformed contact line. We discuss the arising configuration-specificeffects, also in configurations of biomimetic interest. / Doctorat en Sciences de l'ingénieur et technologie / info:eu-repo/semantics/nonPublished

Travel demand management policies such as congestion charges encourage car-users to change among other things route, mode and departure time. Departure time may be especially affected by time-varying charges, since car-users can avoid high peak hour charges by travelling earlier or later, so called peak spreading effects. Conventional transport models do not include departure time choice as a response. For evaluation of time-varying congestion charges departure time choice is essential. In this thesis a transport model called SILVESTER is implemented for Stockholm. It includes departure time, mode and route choice. Morning trips, commuting as well as other trips, are modelled and time is discretized into fifteen-minute time periods. This way peak spreading effects can be analysed. The implementation is made around an existing route choice model called CONTRAM, for which a Stockholm network already exists. The CONTRAM network has been in use for a long time in Stockholm and an origin-destination matrix calibrated against local traffic counts and travel times guarantee local credibility. On the demand side, an earlier developed departure time and mode choice model of mixed logit type is used. It was estimated on CONTRAM travel times to be consistent with the route choice model. The behavioural response under time-varying congestion charges was estimated from a hypothetical study conducted in Stockholm. Paper I describes the implementation of SILVESTER. The paper shows model structure, how model run time was reduced and tests of convergence. As regards run time, a 75% cut down was achieved by reducing the number of origin-destination pairs while not changing travel time and distance distributions too much. In Paper II car-users underlying preferred departure times are derived using a method called reverse engineering. This method derives preferred departure times that reproduce as well as possible the observed travel pattern of the base year. Reverse engineering has previously only been used on small example road networks. Paper II shows that application of reverse engineering to a real-life road network is possible and gives reasonable results. / <p>QC 20170222</p> / Silvester

The web has granted everyone the opportunity to freely share large amounts of data. Individuals, corporations, and communities have made the web an important tool in their arsenal. These entities are spreading information online, but not all of it is constructive. Some spread misinformation to protect themselves or to attack other entities or ideas on the web. Checking the integrity of all the information online is a complex problem and an ethical solution would be equally complex. Multiple latent factors decide how a topic spreads and finding these factors is non-trivial. In this thesis, the patterns of different topics are compared with each other and the generalized patterns of fake, true, and mixed news, using Latent Dirichlet Allocation (LDA) topic models. We look at how the dissemination of topics can be compared through different metrics, and how these can be calculated through networks related to the data.  The analyzed data was collected using the Twitter API and news article scrapers. From this data, custom corpora were made through lemmatization and filtering unnecessary words and characters. The LDA models were made using these corpora, making it possible to extract the latent topics of the articles. By plotting the articles according to their most dominant topic, graphs for the popularity, size, and other distribution statistics could easily be drawn. From these graphs, the topics could be compared to each other and be categorized as fake, true, or mixed news by looking at their patterns and novelty. However, this brought up the question if it would be ethical to generalize topics in this way. Suppressing or censuring an article because it contains a lot of novel information might hide constructive novelties and violate freedom of speech. Finally, this thesis presents the means for further work in the future, which could involve collecting one large, continuous dataset for a fair and accurate comparison between topics.

En ohållbar resursanvändning har lett till att resurser länge lagts i osorterade deponier, vilket leder till att farliga ämnen lakas ur och förorenar sjöar och vattendrag. Klimatförändringar som förväntas leda till stigande havsnivåer gör att deponier i närheten till hav, sjöar och vattendrag kan komma att sprida föroreningar i större utsträckning än de gör idag. För att bidra till ytterligare kunskap kring ämnet har metallhalten i två gamla deponier intill Mälaren undersökts. Studien baseras på en fältundersökning där mark och grundvattenprover samlats in, analyserats och kategoriserats enligt MIFOs principer: farlighet, föroreningsnivå och spridningsrisk. Utgångspunkten är att skyddsvärdet är stort då området angränsar till Mälaren. Det undersökta området omfattas av två deponier (Ekudden och Uddhagen) i anslutning till varandra och undersöks därför samtidigt. Studiens syfte är att identifiera områden med punktkällor där åtgärder bör vidtas för att minimera risken för en kontaminering av Mälarens vatten nu och i framtiden. Studien visade att samtliga provpunkter överskred halter för KM (känslig markanvändning) för en eller flera metaller. Genom en visualisering kunde sex områden identifieras där en eller flera provpunkter visade på halter där minst tre ämnen överskrider halten för MKM (mindre känslig markanvändning), eller där en eller flera ämnen överskrider halten för FA (farligt avfall). Då områdets avgränsning inte var tillräckligt tydlig kunde inte alla provpunkterna ses som punktkällor. Två områden anses ha två eller fler punktkällor som sprider föroreningar. Punktkällorna är belägna på en kampingplats där halter för KM inte bör överskridas. Fyra områden anses ha delområden som utgörs av provpunkterna där halterna är högre än övriga provpunkter. Fyra punkter anses även ligga så pass nära strandkanten att en höjning av Mälaren skulle kunna leda till en översvämning av provpunkterna vilket kan innebära en ökad risk för kontaminering av ytvattnet. En åtgärd som föreslås för att minimera risken för fortsatt urlakning är en välplanerad bioremediering i kombination med fytoremediering då stora delar idag används i rekreationella syften. Structor miljöteknik AB på uppdrag av Kungsörs kommun / The unsustainableuse of resources has resulted inresiduesbeing put into unsorted landfills for a long time, this practice has ledto hazardous substances being leached out and polluting lakes and watercourses. Climate changeis leadingto rising sea levels, whichmay result inthat landfills in vicinity of seas, lakes and watercourses may spread pollution to a greater extent than they do today. To contribute to further knowledge about thissubject, the metal content in two old landfills next to Lake Mälaren has been investigated. The study is based on a field survey where soil and groundwater samples were collected, analyzed and categorized according to MIFO's principles: hazard, pollution level and risk of spreading. The starting point is that the protection value is large as the area borders Lake Mälaren. The investigated area is covered by two landfills (Ekudden and Uddhagen) adjacent to each other and because of that the areas areinvestigated at the same time. The purpose of the study was to identify hotspots of pollutants,where measures should be taken to minimize the risk of contamination of the lakenow and in the future. The study showed that all test points exceeded levels for KM (sensitive land use) for one or more metals. Through a visualization, six areas could be identified where one or more test points showed levels where at least three substances exceed the level for MKM (less sensitive land use), or where one or more substances exceed the level for FA (hazardous waste). As the demarcation of the area was not clear enough, not all test points could countas hotspots.Two areas are considered to have two or morehotspotsthat spread pollutants. The hotspot-areasare located on a campsite where levels for KM should not be exceeded. Four areas are considered assub-areas, these sub-areasconsist of the test points where pollutantsare high, but the demarcation of the area is uncertain.Four areasare also considered to be at risk if lake Mälaren shouldincrease which could lead to a flood of the test pointsandmay entail an increased risk of contamination of the surface water. One measure that is proposed to minimize the risk of continued leaching is a well-planned bioremediation in combination with phytoremediation as large parts of the investigated area iscurrently used for recreational purposes

Dans les tissus, les cellules génèrent et sont soumises en permanence à des forces mécaniques. Les perturbations biochimiques à l'intérieur des cellules, ainsi que les altérations de leur environnement mécanique peuvent modifier l'équilibre physiologique et mener à des pathologies, comme le cancer. Bien que les propriétés mécaniques puissent être modifiées à l'échelle du tissus, la compréhension de la mécanique au niveau de la cellule unique demeure importante. En particulier, la différenciation, la migration des cellules immunitaires et le caractère invasif d'un cancer dépendent fortement des propriétés mécaniques des cellules uniques. Les déformations mécaniques peuvent induire un changement de la surface et du volume cellulaires. Nous nous intéressons particulièrement à la régulation du volume cellulaire chez les cellules mammifères dans le contexte de déformations à différentes échelles de temps. Jusqu'à présent, la régulation du volume dans ce contexte n'a été que très peu étudiée, en raison de la difficulté d'obtention de mesures précises, et du fait que le volume de la cellule est généralement considéré comme constant. Nous avons développé une méthode de mesure du volume cellulaire reposant sur l'exclusion de fluorescence, qui nous permet d'effectuer des mesures de volume précise au niveau de la cellule unique. Dans cette étude, nous nous sommes concentrés sur la régulation du volume cellulaire au cours de l'étalement dynamique sur un substrat (échelle de temps : minutes). Nous avons démontré qu'il existe différents régimes de régulation du volume lors de l'étalement : les cellules réduisent, augmentent ou ne modifient pas leur volume, en fonction de l'état du cortex d'actomyosine et de la vitesse d'étalement. Nous avons constaté que les cellules s'étalant plus vite ont tendance à perdre davantage de volume. Notre hypothèse est que lors d'une extension rapide de lamellipode dépendante d'Arp2/3, l'actine tire sur la membrane et génère une tension et l'activation de transport ionique, s'accompagnant d'une perte de volume compensatoire. L'inhibition de la polymérisation de l'actine ou de sa ramification dépendante d'Arp2/3 réduit la vitesse d'étalement et ainsi la perte de volume. Nous avons ensuite montré que l'inhibition de la contractilité augmente la vitesse d'étalement et la perte de volume. Cependant, l'inhibition d'Arp2/3 dans des cellules à faible contractilité conduit à un étalement rapide sans perte de volume. En effet, l'inhibition d'Arp2/3 induit des bulles de membranes, une déformation rapide n'induirait donc pas de perte de volume car la cellule peut relâcher la tension en dépliant la membrane. Nous avons également montré que la régulation du volume en réponse à une compression mécanique rapide (échelle de temps : millisecondes) indépendante de l'adhérence dépend également de l'état du cortex d'actomyosine. Les cellules perdent jusqu'à 30% de leur volume lorsqu'elles sont confinées, car la membrane plasmique est attachée au cortex et ne peux pas être dépliée en réponse à l'augmentation de la tension. La perturbation du cortex d'actine induit le détachement de la membrane et limite la perte de volume. Enfin, nous avons montré que la réponse du volume à un choc osmotique (échelle de temps : secondes) est plus que complexe que décrite dans la littérature. Nos données indiquent qu'au niveau de la cellule unique, la réponse initiale du volume au changement de l'osmolarité extérieure n'est pas un processus passif uniforme. En utilisant la technique du choc osmotique, nous avons également confirmé que les cellules ont un large excès de membrane repliée dans des réservoirs. Nos résultats montrent que le volume et l'aire cellulaires sont couplés par l'homéostasie de la tension de surface, et, étant donné que les déformations induisent une augmentation de la tension de surface, elles conduisent à des modifications du volume et de l'aire de la cellule. / The field of biomechanics significantly progressed in the last two decades. The importance of the feedback between biochemical signaling and physical properties was revealed in many studies. Cells within tissues constantly generate and experience mechanical forces. Biochemical perturbations inside the cells as well as alterations in the mechanical environment can shift the tiny balance of normal physiological state and lead to pathologies, e.g. cancer. Although the mechanical properties of individual cells can alter when they are within the tissues, the understanding of single cell mechanics is still important. Differentiation, immune cell migration, and cancer invasion strongly depend on the mechanical properties of individual cells. Mechanical deformations can lead to a change in cell surface area and volume. We are particularly interested in single mammalian cell volume regulation in the context of deformations of different timescales. For the moment, volume regulation in this context was out from the research interest, probably due to the difficulties of accurate measurements, and cell volume often considered as a constant parameter. We developed a method for cell volume measurements based on a fluorescent exclusion that allowed us to perform precise volume measurements of individual live cells. In the present study, we mainly focused on cell volume regulation while dynamic spreading on a substrate (timescale – minutes). We demonstrated that there are different regimes for volume regulation while spreading: cells decrease, increase or do not change volume, and a type of the regime depends on the state of the actomyosin cortex and spreading speed. We obtained that faster-spreading cells tend to lose more volume. Our hypothesis is that during fast Arp2/3-driven lamellipodia extension actin pull on the membrane that generates tension and activation of ion transport and regulatory volume loss. Inhibition of actin polymerization or Arp2/3-dependent actin branching decreases spreading speed and volume loss. Next, we showed that inhibition of contractility increases spreading speed and volume loss. However, inhibition of Arp2/3 complex in cells with low contractility leads to fast spreading without volume loss. Our explanation is that inhibition of Arp2/3 induces cell blebbing and even fast deformation does not lead to volume loss as a cell can relax tension by membrane unfolding. We also showed that volume regulation in response to fast mechanical compression (timescale – milliseconds) independent of adhesion also depends on the actomyosin cortex state. Control cells lose up to 30% of volume under confinement, as the cell membrane is attached to the cortex and cannot be unfolded in response to the tension increase. Disruption of actin cortex leads to membrane detachment and prevents volume loss under confinement. Additionally, we showed that cell volume response to the osmotic shock (timescale – seconds) is more complex than it used to be known in the literature. For instance, our data indicate that at the level of individual cells initial volume response to the change of external osmolarity is not a uniform passive process. Using osmotic shock technique, we also confirmed that cells have a large excess of membrane folded in reservoirs. Taken together, our data show that cell volume and surface area are coupled through surface tension homeostasis and as deformations induce surface tension increase, they lead to change volume and surface area.

La dissémination collaborative d'une information d'un agent à tous les autres agents d'un système distribué est un problème fondamental qui est particulièrement important lorsque l'on veut obtenir des algorithmes distribués qui sont à la fois robustes et fonctionnent dans un cadre anonyme, c'est-à-dire sans supposer que les agents possèdent des identifiants distincts connus. Ce problème, connu sous le nom de problème de propagation de rumeur , est à la base de nombreux algorithmes de communication sur des réseaux de capteurs sans-fil [Dimakis et al. (2010)] ou des réseaux mobiles ad-hoc. Il est aussi une brique de base centrale pour de nombreux algorithmes distribués avancés [Mosk-Aoyama et Shah (2008)].Les méthodes les plus connues pour surmonter les défis de robustesse et d'anonymat sont les algorithmes basés sur les ragots ( gossip-based algorithms ), c'est-à-dire sur la paradigme que les agents contact aléatoirement les autres agents pour envoyer ou récupérer l'information. Nousproposons une méthode générale d'analyse de la performance des algorithmes basés sur les ragots dans les graphes complets. Contrairement aux résultats précédents basés sur la structure précise des processus étudiés, notre analyse est basée sur la probabilité et la covariance des évènements correspondants au fait qu'un agent non-informé s'informe. Cette universalité nous permet de reproduire les résultats basiques concernant les protocoles classiques de push, pull et push-pull ainsi qu'analyser les certaines variantions telles que les échecs de communications ou les communications simultanés multiples réalisées par chaque agent. De plus, nous sommescapables d'analyser les certains modèles dynamiques quand le réseaux forme un graphe aléatoire échantillonné à nouveau à chaque étape [Clementi et al. (ESA 2013)]. Malgré sa généralité, notre méthode est simple et précise. Elle nous permet de déterminer l'espérance du temps de la diffusion à une constante additive près, ce qu'il est plus précis que la plupart des résultatsprécédents. Nous montrons aussi que la déviation du temps de la diffusion par rapport à son espérance est inférieure d'une constante r avec la probabilité au moins 1 − exp(Ω(r)).À la fin, nous discutons d'une hypothèse classique que les agents peuvent répondre à plusieurs appels entrants. Nous observons que la restriction à un seul appel entrant par agent provoque une décélération importante du temps de la diffusion pour un protocole de push-pull. En particulier, une phase finale du processus prend le temps logarithmique au lieu du temps double logarithmique. De plus, cela augmente le nombre de messages passés de Θ(n log log n) (valeur optimale selon [Karp et al. (FOCS 2000)]) au Θ(n log n) . Nous proposons une variation simple du protocole de push-pull qui rétablit une phase double logarithmique à nouveau et donc le nombre de messages passés redescend sur sa valeur optimal. / Epidemic algorithms are distributed algorithms in which the agents in thenetwork involve peers similarly to the spread of epidemics. In this work, we focus on randomized rumor spreading -- a class of epidemic algorithms based on the paradigm that nodes call random neighbors and exchange information with these contacts. Randomized rumor spreading has found numerous applications from the consistency maintenance of replicated databases to newsspreading in social networks. Numerous mathematical analyses of different rumor spreading algorithms can be found in the literature. Some of them provide extremely sharp estimates for the performance of such processes, but most of them are based on the inherent properties of concrete algorithms.We develop new simple and generic method to analyze randomized rumor spreading processes in fully connected networks. In contrast to all previous works, which heavily exploit the precise definition of the process under investigation, we only need to understand the probability and the covariance of the events that uninformed nodes become informed. This universality allows us to easily analyze the classic push, pull, and push-pull protocols both in their pure version and in several variations such as when messages fail with constant probability or when nodes call a random number of others each round. Some dynamic models can be analyzed as well, e.g., when the network is a random graph sampled independently each round [Clementi et al. (ESA 2013)]. Despite this generality, our method determines the expected rumor spreading time precisely apart from additive constants, which is more precise than almost all previous works. We also prove tail bounds showing that a deviation from the expectation by more than an additive number of r rounds occurs with probability at most exp(−Ω(r)).We further use our method to discuss the common assumption that nodes can answer any number of incoming calls. We observe that the restriction that only one call can be answered leads to a significant increase of the runtime of the push-pull protocol. In particular, the double logarithmic end phase of the process now takes logarithmic time. This also increases the message complexity from the asymptotically optimal Θ(n log log n) [Karp, Shenker, Schindelhauer, Vöcking (FOCS 2000)] to Θ(n log n). We propose a simple variation of the push-pull protocol that reverts back to the double logarithmic end phase and thus to the Θ(n log log n) message complexity.

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