Power electronics applications in high power are normally large, expensive, spatially distributed systems. These systems are typically complex and have multiple functions. Due to these properties, the control algorithm and its implementation are challenging, and a different approach is needed to avoid customized solutions to every application while still having reliable sensor measurements and converter communication and control. This thesis proposes a synchronous digital control architecture that allows for the communication and control of devices via a fiber optic communication ring using digital technology. The proposed control architecture is a multidisciplinary approach consisting of concepts from several areas of electrical engineering. A review of the state of the art is presented in Chapter 2 in the areas of power electronics, fieldbus control networks, and digital design. A universal controller is proposed as a solution to the hardware independent control of these converters. Chapter 3 discusses how the controller was specified, designed, implemented, and tested. The power level specific hardware is implemented in modules referred to as hardware managers. A design for a hardware manager was previously implemented and tested. Based on these results and experiences, an improved hardware manager is specified in Chapter 4. A fault tolerant communication protocol is specified in Chapter 5. This protocol is an improvement on a previous version of the protocol, adding benefits of improved synchronization, multimaster support, fault tolerant structure with support for hot-swapping, live insertion and removals, a variable ring structure, and a new network based clock concept for greater flexibility and control. Chapter 6 provides a system demonstration, verifying the components work in configurations involving combinations of controllers and hardware managers to form applications. Chapter 7 is the conclusion. VHDL code is included for the controller, the hardware manager, and the protocol. Schematics and manufacturing specifications are included for the controller. / Master of Science

The LHC (Large Hadron Collider) will have a long shut down in the years of 2019 and 2020, referred to as LS2. During this stop the LHC injector complex will be upgraded to increase the luminosities, which will be the first step of the high luminosity LHC program (which will be realized during LS3 that takes place in 2024-2026). The LHCb experiment, whose main purpose is to study the CP-violation, will during this long stop be upgraded in order to withstand a higher radiation dose, and to be able to read out the detector at a rate of 40MHz,compared to 1MHz at present. This change will improve the trigger efficiency significantly. One of the LHCb sub-detectors the Trigger Tracker (TT), will be replaced by a new sub-detector called UT. This report presents the early stage design (preparation for mock-up building) of the box that will be isolating the new UT detector from the surroundings and to ensure optimal detector operation. Methods to fulfill requirements such as light and gas tightness, Faraday-cage behavior and condensation free temperatures, without breaking the fragile beryllium beam pipe, are established. / LHC (Large Hadron Collider) kommer under åren 2019-2020 att ha ett längre driftstopp. Under detta driftstopp så kommer LHC's injektionsanordningar att uppgraderas för att kunna sätta fler protoner i circulation i LHC, och därmed öka antalet partikelkollisioner per tidsenhet. Denna uppgradering kommer att vara första steget i "High Luminocity LHC"-programmet som kommer att realiseras år 2024-2026. LHCb-experimentet, vars främsta syfte är att studera CP-brott, kommer också att uppgraderas under stoppet 2019-2020. Framför allt så ska avläsningsfrekvensen ökas från dagens 1MHz till 40MHz, och experimentet ska förberedas för de högre strålningsdoser som kommer att bli aktuella efter stoppet 2024-2026. En av LHCb's deldetektorer, TT detektorn, kommer att bytas ut mot en ny deldetektor som kallas UT. Den här rapporten presenterar den förberedande designen av den låda som ska isolera UT från dess omgivning och försäkra optimala förhållanden för detektorn. Kraven på den isolerande lådan och tillvägagångssätt för att uppfylla dessa krav presenteras. / LHCb, LS2 and LS3 Upgrade

<div>Adsorbent technology is widely used in many industrial applications including waste heat recovery, water purification, and atmospheric revitalization in confined habitations. Astronauts depend on adsorbent-based systems to remove metabolic carbon dioxide (CO₂) from the cabin atmosphere; as NASA prepares for the journey to Mars, engineers are redesigning the adsorbent-based system for reduced weight and optimal efficiency. These efforts hinge upon the development of accurate, predictive models, as simulations are increasingly relied upon to save cost and time over the traditional design-build-test approach. Engineers rely on simplified models to reduce computational cost and enable parametric optimizations. Amongst these simplified models is the axially dispersed plug-flow model for predicting the adsorbate concentration during flow through an adsorbent bed. This model is ubiquitously used in designing fixed-bed adsorption systems. The current work aims to improve the accuracy of the axially dispersed plug-flow model because of its wide-spread use. This dissertation identifies the critical model inputs that drive the overall uncertainty in important output quantities then systematically improves the measurement and prediction of these input parameters. Limitations of the axially dispersed plug-flow model are also discussed, and recommendations made for identifying failure of the plug-flow assumption.</div><div><br></div><div>An uncertainty and sensitivity analysis of an axially disperse plug-flow model is first presented. Upper and lower uncertainty bounds for each of the model inputs are found by comparing empirical correlations against experimental data from the literature. Model uncertainty is then investigated by independently varying each model input between its individual upper and lower uncertainty bounds then observing the relative change in predicted effluent concentration and temperature (<i>e.g.</i>, breakthrough time, bed capacity, and effluent temperature). This analysis showed that the LDF mass transfer coefficient is the largest source of uncertainty. Furthermore, the uncertainty analysis reveals that ignoring the effect of wall-channeling on apparent axial dispersion can cause significant error in the predicted breakthrough times of small-diameter beds.</div><div><br></div><div>In addition to LDF mass transfer coefficient and axial-dispersion, equilibrium isotherms are known to be strong lever arms and a potentially dominant source of model error. As such, detailed analysis of the equilibrium adsorption isotherms for zeolite 13X was conducted to improve the fidelity of CO₂ and H₂O on equilibrium isotherms compared to extant data. These two adsorbent/adsorbate pairs are of great interest as NASA plans to use zeolite 13X in the next generation atmospheric revitalization system. Equilibrium isotherms describe a sorbent’s maximum capacity at a given temperature and adsorbate (<i>e.g.</i>, CO₂ or H₂O) partial pressure. New isotherm data from NASA Ames Research Center and NASA Marshall Space Flight Center for CO₂ and H₂O adsorption on zeolite 13X are presented. These measurements were carefully collected to eliminate sources of bias in previous data from the literature, where incomplete activation resulted in a reduced capacity. Several models are fit to the new equilibrium isotherm data and recommendations of the best model fit are made. The best-fit isotherm models from this analysis are used in all subsequent modeling efforts discussed in this dissertation.</div><div><br></div><div>The last two chapters examine the limitations of the axially disperse plug-flow model for predicting breakthrough in confined geometries. When a bed of pellets is confined in a rigid container, packing heterogeneities near the wall lead to faster flow around the periphery of the bed (<i>i.e.</i>, wall channeling). Wall-channeling effects have long been considered negligible for beds which hold more than 20 pellets across; however, the present work shows that neglecting wall-channeling effects on dispersion can yield significant errors in model predictions. There is a fundamental gap in understanding the mechanisms which control wall-channeling driven dispersion. Furthermore, there is currently no way to predict wall channeling effects a priori or even to identify what systems will be impacted by it. This dissertation aims to fill this gap using both experimental measurements and simulations to identify mechanisms which cause the plug-flow assumption to fail.</div><div><br></div><div>First, experimental evidence of wall-channeling in beds, even at large bed-to-pellet diameter ratios (<i>d</i>_bed/<i>d</i>_p=48) is presented. These experiments are then used to validate a method for accurately extracting mass transfer coefficients from data affected by significant wall channeling. The relative magnitudes of wall-channeling effects are shown to be a function of the adsorption/adsorbate pair and geometric confinement (<i>i.e.</i>, bed size). Ultimately, the axially disperse plug-flow model fails to capture the physics of breakthrough when nonplug-flow conditions prevail in the bed.</div><div><br></div><div>The final chapter of this dissertation develops a two-dimensional (2-D) adsorption model to examine the interplay of wall-channeling and adsorption kinetics and the adsorbent equilibrium capacity on breakthrough in confined geometries. The 2-D model incorporates the effect of radial variations in porosity on the velocity profile and is shown to accurately capture the effect of wall-channeling on adsorption behavior. The 2-D model is validated against experimental data, and then used to investigate whether capacity or adsorption kinetics cause certain adsorbates to exhibit more significant radial variations in concentration compared than others. This work explains channeling effects can vary for different adsorbate and/or adsorbent pairs—even under otherwise identical conditions—and highlights the importance of considering adsorption kinetics in addition to the traditional <i>d</i>_bed/<i>d</i>_p criteria.</div><div><br></div><div>This dissertation investigates key gaps in our understanding of fixed-bed adsorption. It will deliver insight into how these missing pieces impact the accuracy of predictive models and provide a means for reconciling these errors. The culmination of this work will be an accurate, predictive model that assists in the simulation-based design of the next-generation atmospheric revitalization system for humans’ journey to Mars.</div>

The constant monitoring of a computer is one of the essentials to be up-to-date about its state. This may seem trivial if one is sitting right in front of it but when monitoring a computer from a certain distance it is not as simple anymore. It gets even more difficult if a large number of computers need to be monitored. Because the process of monitoring always causes some load on the network and the monitored computer itself, it is important to keep these influences as low as possible. Especially for a high-performance cluster that was built from a lot of computers, it is necessary that the monitoring approach works as efficiently as possible and does not influence the actual operations of the supercomputer. Thus, the main goals of this work were, first of all, analyses to ensure the scalability of the monitoring solution for a large computer cluster as well as to prove the functionality of it in practise. To achieve this, a classification of monitoring activities in terms of the overall operation of a large computer system was accomplished first. Thereafter, methods and solutions were presented which are suitable for a general scenario to execute the process of monitoring as efficient and scalable as possible. During the course of this work, conclusions from the operation of an existing cluster for the operation of a new, more powerful system were drawn to ensure its functionality as good as possible. Consequently, a selection of applications from an existing pool of solutions was made to find one that is most suitable for the monitoring of the new cluster. The selection took place considering the special situation of the system like the usage of InfiniBand as the network interconnect. Further on, an additional software was developed which can read and process the different status information of the InfiniBand ports, unaffected by the vendor of the hardware. This functionality, which so far had not been available in free monitoring applications, was exemplarily realised for the chosen monitoring software. Finally, the influence of monitoring activities on the actual tasks of the cluster was of interest. To examine the influence on the CPU and the network, the self-developed plugin as well as a selection of typical monitoring values were used exemplarily. It could be proven that no impact on the productive application for typical monitoring intervals can be expected and only for atypically short intervals a minor influence could be determined. / Die ständige Überwachung eines Computers gehört zu den essentiellen Dingen, die zu tun sind um immer auf dem Laufenden zu sein, wie der aktuelle Zustand des Rechners ist. Dies ist trivial, wenn man direkt davor sitzt, aber wenn man einen Computer aus der Ferne beobachten soll ist dies schon nicht mehr so einfach möglich. Schwieriger wird es dann, wenn es eine große Anzahl an Rechnern zu überwachen gilt. Da der Vorgang der Überwachung auch immer etwas Netzwerklast und Last auf dem zu überwachenden Rechner selber verursacht, ist es wichtig diese Einflüsse so gering wie möglich zu halten. Gerade dann, wenn man viele Computer zu einem leistungsfähigen Cluster zusammen geschalten hat ist es notwendig, dass diese Überwachungslösung möglichst effizient funktioniert und die eigentliche Arbeit des Supercomputers nicht stört. Die Hauptziele dieser Arbeit sind deshalb Analysen zur Sicherstellung der Skalierbarkeit der Überwachungslösung für einen großen Computer Cluster, sowie der praktische Nachweis der Funktionalität dieser. Dazu wurde zuerst eine Einordnung des Monitorings in den Gesamtbetrieb eines großen Computersystems vorgenommen. Danach wurden Methoden und Lösungen aufgezeigt, welche in einem allgemeinen Szenario geeignet sind, um den ganzheitlichen Vorgang der Überwachung möglichst effizient und skalierbar durchzuführen. Im weiteren Verlauf wurde darauf eingegangen welche Lehren aus dem Betrieb eines vorhandenen Clusters für den Betrieb eines neuen, leistungsfähigeren Systems gezogen werden können um dessen Funktion möglichst gut gewährleisten zu können. Darauf aufbauend wurde eine Auswahl getroffen, welche Anwendung aus einer Menge existierende Lösungen heraus, zur Überwachung des neuen Clusters besonders geeignet ist. Dies fand unter Berücksichtigung der spezielle Situation, zum Beispiel der Verwendung von InfiniBand als Verbindungsnetzwerk, statt. Im Zuge dessen wurde eine zusätzliche Software entwickelt, welche die verschiedensten Statusinformationen der InfiniBand Anschlüsse auslesen und verarbeiten kann, unabhängig vom Hersteller der Hardware. Diese Funktionalität, welche im Bereich der freien Überwachungsanwendungen bisher ansonsten noch nicht verfügbar war, wurde beispielhaft für die gewählte Monitoring Software umgesetzt. Letztlich war der Einfluss der Überwachungsaktivitäten auf die eigentlichen Anwendungen des Clusters von Interesse. Dazu wurden exemplarisch das selbst entwickelte Plugin sowie eine Auswahl an typischen Überwachungswerten benutzt, um den Einfluss auf die CPU und das Netzwerk zu untersuchen. Dabei wurde gezeigt, dass für typische Überwachungsintervalle keine Einschränkungen der eigentlichen Anwendung zu erwarten sind und dass überhaupt nur für untypisch kurze Intervalle ein geringer Einfluss festzustellen war.

Im Rahmen der vorliegenden Diplomarbeit wurden etablierte Systemsoftware-Updatefunktionen von DVB-Empfangsgeräten untersucht. Auf der Grundlage einer gezielten Analyse der Nutzersicht auf diese Systeme wurden dabei wiederkehrende Problematiken in der Durchführung aufgedeckt und mangelhafte Benutzer-Transparenz sowie deren Konsequenzen beleuchtet. Die Studie erfolgt in Form einer Online-Umfrage unter Nutzern themenbezogener Fach- bzw. Diskussionsforen. Mittels einer kritischen Bewertung der existierenden Systemsoftware-Updatemodelle unter gleichzeitiger Berücksichtigung der Hersteller- und Nutzerinteressen erfolgte eine Favorisierung, bei welcher die Updatemethoden „Over the Air“ und „Internet“ die günstigsten Voraussetzungen zeigten. An diesen wurden Ideenansätze mit dem Ziel einer weitergehenden Modelloptimierung diskutiert und konkretisiert. Im Ergebnis erwies sich die optimierte Variante der Updatemethode „Internet“ im Sinne der untersuchten Aspekte als besonders zweckmäßig. Als Praxisversuch wurde eine Systemsoftware-Updatefunktion unter Einbeziehung der Verbesserungen in einer VDR-Umgebung erfolgreich implementiert und getestet. Der großen Funktionsvielfalt dieses Multimedia-Entertainment-Systems und der Überschaubarmachung dieser für den Nutzer wurde dabei Rechnung getragen.

The well-to-wheel (WTW) environmental performance of plug-in hybrid electric vehicles (PHEVs) is sensitive to driving patterns, which vary within and across regions. This thesis develops and applies a novel approach for estimating specific regional driving patterns. The approach employs a macroscopic traffic assignment model linked with a vehicle motion model to construct driving cycles, which is done for a wide range of driving patterns. For each driving cycle, the tank-to-wheel energy use of two PHEVs and comparable non-plug-in alternatives is estimated. These estimates are then employed within a WTW analysis to investigate implications of driving patterns on the energy use and greenhouse gas emission of PHEVs, and the WTW performance of PHEVs relative to non-plug-in alternatives for various electricity generation scenarios. The results of the WTW analysis demonstrate that driving patterns and the electricity generation supply interact to substantially impact the WTW performance of PHEVs.

The well-to-wheel (WTW) environmental performance of plug-in hybrid electric vehicles (PHEVs) is sensitive to driving patterns, which vary within and across regions. This thesis develops and applies a novel approach for estimating specific regional driving patterns. The approach employs a macroscopic traffic assignment model linked with a vehicle motion model to construct driving cycles, which is done for a wide range of driving patterns. For each driving cycle, the tank-to-wheel energy use of two PHEVs and comparable non-plug-in alternatives is estimated. These estimates are then employed within a WTW analysis to investigate implications of driving patterns on the energy use and greenhouse gas emission of PHEVs, and the WTW performance of PHEVs relative to non-plug-in alternatives for various electricity generation scenarios. The results of the WTW analysis demonstrate that driving patterns and the electricity generation supply interact to substantially impact the WTW performance of PHEVs.

L’apparition massive des véhicules électriques (VEs) sur les marchés peut avoir un impact important sur le fonctionnement des réseaux d’électricité actuels qui devront ajuster leur fonctionnement à la nouvelle demande massive d'électricité provenant des VEs. Par contre, les VEs peuvent aussi être vus comme une nouvelle opportunité dans le futur marché d’électricité. En effet, une décharge/recharge intelligente peut permettre aux VEs d’être un support de stockage d’électricité important, valable et permanent dont la capacité croit en fonction du nombre des VEs. Ce projet a comme objectifs de : (1) proposer un schéma d’interaction V2G intégrant des techniques permettant de : (a) adapter le fonctionnement de la grille aux contraintes temporelles et spatiales relatives au processus de recharge des VEs dans un milieu résidentiel. (b) optimiser les opérations de chargement/déchargement entre les VEs et la grille dans les deux sens. (2) Proposer de nouveaux schémas de communication sans fil, entre les VEs et la grille intelligente loin des bornes de recharge, qui soient basés sur les standards de communications véhiculaires (VANET) ainsi que sur d’autres standards de communication à grande échelle. On introduira des techniques d’accès à la grille intelligente pour négocier le coût de recharge/décharge des batteries et aussi pour planifier la motivation du consommateur afin de favoriser la stabilité de la grille / In the next years, electric vehicles (EVs) will make their appearance on the market. This even will have significant impact on the operation of the existing electricity networks which have to be updated to reach the new massive electricity demand. Moreover, EVs can also be seen as a new opportunity in the future electricity market. Indeed, a smart EV discharge / charge process can be enable a large power, valuable, and permanent storage media. The project's objectives are to: (1) propose a scheme integrating V2G interaction techniques: (a) adapt the grid functionality to the temporal and spatial constraints to the EV charging process in a residential setting. We seek to satisfy different power demands of EVs connected to the mains without stressing too smart grid, (b) optimizing the loading / unloading between EVs and the grid in both directions. (2) To propose new patterns of wireless communication between EVs and smart grid away from the charging stations, which are based on the standards of vehicle communications (VANET), as well as other communication standards on a large scale. Access to smart grid technologies will be introduced to negotiate the cost of charge / discharge, the waiting time of service, locations and also to plan consumer motivation to promote the grid stability

This work thoroughly analyzes a previously created computational model for predicting characteristic properties of the combustion process in an experimental combustion chamber. Any found shortcomings of the original model are removed and the model is further improved prior to its application on 11 real cases of combustion tests performed at various conditions and with various fuels. Data provided by the model are confronted with the data obtained during the combustion tests and the model accuracy is evaluated, based on local heat flux along the length of the combustion chamber. Finally, the overall usefulness of the model is determined by the means of evaluating the acquired accuracy values, and further possibilities of model improvement and use are presented.

Purpose of this thesis is to design and implement a tool for automatic categorization of photos. The proposed tool is based on the Bag of Words classification method and it is realized as a plug-in for the XnView image viewer. The plug-in is able to classify a selected group of photos into predefined image categories. Subsequent notation of image categories is written directly into IPTC metadata of the picture as a keyword.