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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
161

Modeling, Sizing and Control of Plug-in Light Duty Fuel Cell Hybrid Electric Vehicle

Choi, Tayoung Gabriel January 2008 (has links)
No description available.
162

Improving the Energy Density of Hydraulic Hybrid Vehicle (HHVs) and Evaluating Plug-In HHVs

Zeng, Xianwu 16 June 2009 (has links)
No description available.
163

Planning and Control of Safety-Aware Plug & Produce

Massouh, Bassam January 2024 (has links)
The Plug & Produce manufacturing system is a visionary concept that promises to facilitate the seamless integration and adaptation of manufacturing resources and production processes. The Plug & Produce control system allows for the automatic addition and removal of manufacturing resources, minimizing human intervention. However, the reconfigurability and autonomous decision-making features of Plug & Produce control systems pose challenges to safety design and control functions. In contrast to conventional manufacturing systems with fixed layouts and processes, ensuring safety in Plug & Produce systems is complicated due to the complex risk assessment process, the difficulty of implementing non-restrictive safety measures covering all possible hazards, and the challenge of designing a reliable controller for consistent safe operation. This thesis addresses these challenges through various contributions. It introduces an automatic hazard identification method, considering emergent hazards after reconfiguration. A novel domain ontology is developed, incorporating safety models specific to Plug & Produce systems. The work also proposes a generic, model-based, and automatic risk assessment method, along with a method for the safe execution of plans based on the results of the risk assessment. The results of this research offer benefits to process planners, who are responsible for coordinating the manufacturing processes with product design in the Plug & Produce system. The proposed solution provides tools for process planners to validate their plans and reduces their safety-related responsibilities. The proposed safety assurance method seamlessly integrates into the multi-agent control of Plug & Produce, providing the control system with risk scenarios associated with process plans. This enables proactive and reliable control, effectively avoiding potential risks during system operation. / Föreställ dig en automatiserad produktionsanläggning som omedelbart och automatiskt kan anpassa sig till förändringar utan att kompromissa med säkerheten för den personal som arbetar där. Denna avhandling strävar efter att uppnå just detta genom ett smartare sätt att säkerställa att produktionsanläggningar baserat på Plug & Produce kan hantera säkerhet. Dettainnebär att konceptet Plug & Produce nu närmar sig ett industriellt förverkligande. Säkerhet för automatiserade produktionsanläggningar innebär att alla maskiner ska vara utrustade med skydd för att göra arbetet säkrare. Idag är det vanligt med övervakning som skydd, dvs en dator som övervakar att allt går rätt till och stänger av om något är på väg att hända. I ett produktionsavsnitt som är baserat på Plug & Produce kan man enkelt ställa om, det vill säga, lägga till eller ta bort maskiner, ändra layouten eller ändra på produkter som produceras. Efter en sådan omställning så måste säkerheten i produktionsanläggningen ses över enligt föreskrivna lagar och regler. Traditionellt så kräver detta anlitande av en säkerhetsexpert. Detta medför att en omställning utifrån ett säkerhetsperspektiv är både kostsamt och tidskrävande. Med resultatet från denna avhandling så går det nu att ställa om utan att behöva implementera nya säkerhetsfunktioner efter varje förändring. Denna forskning har utvidgat kunskapsområdet inom produktionsteknik för att skapa en "smartarefabrik" genom att inkludera säkerhetsfunktioner.Resultatet inkluderar algoritmer som kan upptäcka potentiella faror i fabriken och automatiskt tillämpa säkerhetsåtgärder för ett övervakat system. Detta innebär mindre tidsåtgång och lägre kostnader för säkerhetsarbetet. De som drar mest nytta av detta är människorna som planerar för hur saker skall tillverkas med hjälp av Plug & Produce. Resultatet av detta arbete underlättar deras arbetsuppgifter och bevarar flexibiliteten i Plug & Produce, vilket eliminerar behovet av att välja mellan flexibilitet och säkerhet
164

A Data Driven Real Time Control Strategy for Power Management of Plug-in Hybrid Electric Vehicles

Abbaszadeh Chekan, Jafar 29 May 2018 (has links)
During the past two decades desperate need for energy-efficient vehicles which has less emission have led to a great attention to and development of electrified vehicles like pure electric, Hybrid Electric Vehicle (HEV) and Plug-in Hybrid Electric Vehicles (PHEVs). Resultantly, a great amount of research efforts have been dedicated to development of control strategies for this type of vehicles including PHEV which is the case study in this thesis. This thesis presents a real-time control scheme to improve the fuel economy of plug-in hybrid electric vehicles (PHEVs) by accounting for the instantaneous states of the system as well as the future trip information. To design the mentioned parametric real-time power management policies, we use dynamic programming (DP). First, a representative power-split PHEV powertrain model is introduced, followed by a DP formulation for obtaining the optimal powertrain trajectories from the energy cost point of view for a given drive cycle. The state and decision variables in the DP algorithm are selected in a way that provides the best tradeoff between the computational time and accuracy which is the first contribution of this research effort. These trajectories are then used to train a set of linear maps for the powertrain control variables such as the engine and electric motor/generator torque inputs, through a least-squares optimization process. The DP results indicate that the trip length (distance from the start of the trip to the next charging station) is a key factor in determining the optimal control decisions. To account for this factor, an additional input variable pertaining to the remaining length of the trip is considered during the training of the real-time control policies. The proposed controller receives the demanded propulsion force and the powertrain variables as inputs, and generates the torque commands for the engine and the electric drivetrain system. Numerical simulations indicate that the proposed control policy is able to approximate the optimal trajectories with a good accuracy using the real-time information for the same drive cycles as trained and drive cycle out of training set. To maintain the battery state-of-charge (SOC) above a certain lower bound, two logics have been introduced a switching logic is implemented to transition to a conservative control policy when the battery SOC drops below a certain threshold. Simulation results indicate the effectiveness of the proposed approach in achieving near-optimal performance while maintaining the SOC within the desired range. / MS
165

Exploring the inclusivity of electric vehicle infrastructure : Neighbourhood demographics and public charging accessibility in Gothenburg, Sweden

Newton, Sarah January 2024 (has links)
This thesis explores the intersection of spatial accessibility, social equity, and neighbourhood demographics within the context of emerging urban challenges related to plug-in electric vehicle (PEV) infrastructure. Incorporating sociological theories such as spatial accessibility and spatial segregation, combined with statistical methods including network routing analyses and multilevel modelling, it examines how neighbourhood demographics shape patterns of spatial accessibility to public charging infrastructure across the city of Gothenburg. In considering neighbourhood demographics in urban planning processes, municipalities can develop more equitable urban development strategies that facilitate EV adoption outside of prevalent demographics. The findings highlight current disparities in access to public charging opportunities, particularly in segregated neighbourhoods, and stress the need for targeted planning strategies to promote social inclusion in this area. This can contribute to local PEV charging network expansion by providing key insights and points for further research and provides a foundation for discussions on related areas, including the provision of emerging transport initiatives such as public car-sharing points.
166

Framtidens produktionspersonal i den Smarta fabriken / The production staff of the future within the smart factory

Nilsson, Amanda, Lindqvist, Hanna January 2016 (has links)
The project has explored the topic Smart factory with main focus on the future production staff. The project aims to investigate how the production staff is affected by Volvo Cars Skövde Engine Plant (SkEP) becoming a Smart factory, in the era of Industry 4.0. The definition of the Smart factory is a demand of Mobile- and wireless technologies, Human-oriented, pursue a Flexible production with Sustainable manufacturing, as well as utilization of CPS (Cyber-Physical Systems), IoT (Internet-of-Things) and Cloud storage. The current situation and the future five to twenty years were examined in order to define the future production staff. This by conducting an observational study and several interviews. The studies’ results were that SkEP cannot be regarded as smart since several demands are inadequate by definition. Five years are considered too short of a time for the plant to fulfill the demands. However, according to the interviews and literature, SkEP are expected to become smart in twenty years after time refinement of existing technologies and implementation of new ones. The authors estimate Leadership, Information, IT and Production lay-out to be the areas that require the most effort. The future production staff are expected to be flexible with workplace, working hours and able to manage multiple variants. They should be included in self-supporting teams where every individual possesses an expertise, are motivated and participating. Production staff should perform complex, varied jobs with more responsibility by endorsement of decision support systems. The staffs’ competence should consist of technical education, high basic and lay-out knowledge and the ability to contribute to the collection of information and analyses. Interaction with technology is expected to expand and the personnel must therefore have a well-established comprehension of technology. The concept Smart factory is extensive and relatively new, which means that it is constantly evolving. Thus it is important for SkEP to be updated and adjust to the impact from the outside world.
167

Aggregation of Plug-in Electric Vehicles in Power Systems for Primary Frequency Control

Izadkhast, Seyedmahdi January 2017 (has links)
The number of plug-in electric vehicles (PEVs) is likely to increase in the near future and these vehicles will probably be connected to the electric grid most of the day time. PEVs are interesting options to provide a wide variety of services such as primary frequency control (PFC), because they are able to quickly control their active power using electronic power converters. However, to evaluate the impact of PEVs on PFC, one should either carry out complex and time consuming simulation involving a large number of PEVs or formulate and develop aggregate models which could efficiently reduce simulation complexity and time while maintaining accuracy. This thesis proposes aggregate models of PEVs for PFC. The final aggregate model has been developed gradually through the following steps. First of all, an aggregate model of PEVs for the PFC has been developed where various technical characteristics of PEVs such as operating modes (i.e., idle, disconnected, and charging) and PEV’s state of charge have been formulated and incorporated. Secondly, some technical characteristics of distribution networks have been added to the previous aggregate model of PEVs for the PFC. For this purpose, the power consumed in the network during PFC as well as the maximum allowed current of the lines and transformers have been taken into account. Thirdly, the frequency stability margins of power systems including PEVs have been evaluated and a strategy to design the frequency-droop controller of PEVs for PFC has been described. The controller designed guaranties similar stability margins, in the worst case scenario, to those of the system without PEVs. Finally, a method to evaluate the positive economic impact of PEVs participation in PFC has been proposed. / En el futuro cercano se espera un notable incremento en el número de vehículos eléctricos enchufables (PEVs), los cuales están conectados a la red eléctrica durante la mayor parte del día. Los PEVs constituyen una opción interesante a la hora de proporcionar una amplia variedad de servicios, tales como el control primario de frecuencia (PFC), dado que tienen la capacidad de controlar rápidamente el flujo de potencia activa a través de convertidores electrónicos de potencia. Sin embargo, para evaluar el impacto de los PEVs sobre el PFC se debe llevar a cabo una simulación computacionalmente compleja y con un largo tiempo de simulación en la que se considere un gran número de PEVs. Otra opción sería la formulación y desarrollo de modelos agregados, los cuales podrían reducer eficazmente la complejidad y tiempo de simulación manteniendo una alta precisión. Esta tesis propone modelos agregados de PEVs para PFC. El modelo agregado definitivo ha sido desarrollado de manera gradual a través de los siguientes pasos. En primer lugar, se ha desarrollado un modelo agregado de PEVs para PFC en el cual son incorporadas varias características técnicas de los PEVs, tales como los modos de operación (inactivo, desconectado y cargando), y la formulación del estado de carga de los PEVs. En segundo lugar, ciertas características técnicas de las redes de distribución han sido consideradas en el modelo agregado de PEVs para PFC previamente propuesto. Para este fin, la potencia consumida por la red durante el PFC, así como la corriente máxima permitida en las líneas y transformadores han sido consideradas. En tercer lugar, se han evaluado los márgenes de estabilidad en la frecuencia de los sistemas de potencia que incluyen PEVs y se ha descrito una estrategia para diseñar un control de frecuencia-droop de PEVs para PFC. El controlador diseñado garantiza márgenes de estabilidad similares, en el peor de los casos, a aquellos de un sistema sin PEVs. Finalmente, se ha propuesto un método para evaluar el impacto económico positivo de la participación de los PEVs en el PFC. / Inom en snar framtid förväntas antalet laddbara bilar (laddbilar) öka kraftig, vilka tidvis kommer att vara anslutna till elnätet. Då laddbilar snabbt kan styra och variera sin aktiva laddningseffekt med hjälp av kraftelektroniken i omriktaren kan dessa fordon erbjuda en rad systemtjänster, såsom primär frekvensregleringen. Att utvärdera hur laddbilarna kan påverka den primära frekvensreglering är utmanande då en stor mängd laddbilar måste beaktas vilket kräver komplexa och tidskrävande simuleringar. Ett effektivt sätt att minska komplexiteten men bibehålla noggrannheten är genom att utforma och använda aggregerade modeller. Syftet med denna avhandling är att ta fram aggregerade modeller för laddbilars påverkan på primär frekvensreglering. Modellen har gradvis utvecklats genom följande steg. I första steget har en aggregerad modell av hur laddbilar kan användas för primär frekvensreglering utvecklats där olika tekniska detaljer så som laddbilars tillstånd (d.v.s. inkopplade, urkopplade eller laddas) och laddningnivån beaktats. I andra steget har en modell av distributionsnätet integrerats i den aggregerade modellen. Här tas hänsyn till effektflöden i elnätet samt begränsningar i överföringskapacitet i transformatorer och ledningar i distributionsnätet. I ett tredje steg har frekvensstabiliteten i ett elnät med laddbilar utvärderats och en strategi för hur en frekvensregulator kan designas för att tillhandahålla primär frekvensreglering med hjälp av laddbilar har utvecklats. Designen garanterar samma stabilitetsmarginal för styrsystemet både med och utan laddbilar. Dessutom föreslås en metod för att utvärdera de ekonomiska effekterna av att använda laddbilar för primär frekvensreglering. / Het aantal elektrische voertuigen (EV’s) zal zeer waarschijnlijk toenemen in de nabije toekomst en deze voertuigen zullen vermoedelijk gedurende het grootste deel van de dag aan het elektriciteitsnetwerk aangesloten zijn. EV’s zijn interessante opties om een grote verscheidenheid van diensten te leveren, zoals bijvoorbeeld primaire frequentieregeling, omdat ze snel hun actieve vermogen kunnen aanpassen met behulp van elektronische vermogensomvormers. Echter, om de invloed van EV’s en primaire frequentieregeling te kunnen evalueren, moet men complexe en tijdrovende simulaties met een groot aantal EVs uitvoeren of verzamelmodellen formuleren en ontwikkelen die de complexiteit en duur van de simulaties kunnen reduceren zonder nauwkeurigheid te verliezen. Dit onderzoek presenteert verzamelmodellen voor EV’s en primaire frequentieregeling. Het uiteindelijke verzamelmodel is geleidelijk ontwikkeld door de volgende stappen te nemen. Ten eerste is een verzamelmodel voor EV’s en primaire frequentieregeling ontwikkeld waar verscheidene technische karakteristieken van EV’s, zoals bedieningsmodi (bijv. Inactief, losgekoppeld en ladend) en de actuele laadtoestand in zijn geformuleerd en geïntegreerd. Ten tweede zijn enkele technische karakteristieken van distributienetwerken toegevoegd aan het eerdere verzamelmodel van EV’s voor primaire frequentieregeling. Hiervoor zijn de vermogensconsumptie in het network gedurende primaire frequentieregeling en de maximaal toegestane stroomsterkte van de kabels meegerekend. Ten derde zijn de marges voor de frequentiestabiliteit van elektriciteitssystemen met EV’s geëvalueerd en is een strategie voor het ontwerpen van de frequentie-droop regeling van de EV’s voor primaire frequentieregeling beschreven. De ontworpen controller garandeert soortgelijke stabiliteitsmarges in het slechtste scenario, als voor het systeem zonder EV’s. Ten slotte is er een methode voorgesteld om de positieve economische invloed van EV-participatie in primaire frequentieregeling te evaluëren. / <p>“SETS Joint Doctorate Programme</p><p>The Erasmus Mundus Joint Doctorate in Sustainable Energy Technologies and Strategies (SETS), the SETS Joint Doctorate, is an international programme run by six institutions in cooperation:</p><p>• Comillas Pontifical University, Madrid, Spain</p><p>• Delft University of Technology, Delft, the Netherlands</p><p>• Florence School of Regulation, Florence, Italy</p><p>• Johns Hopkins University, Baltimore, USA</p><p>• KTH Royal Institute of Technology, Stockholm, Sweden</p><p>• University Paris-Sud 11, Paris, France</p><p>The Doctoral Degrees provided upon completion of the programme are issued by Comillas Pontifical University, Delft University of Technology, and KTH Royal Institute of Technology.</p><p>The Degree Certificates are giving reference to the joint programme. The doctoral candidates are jointly supervised, and must pass a joint examination procedure set up by the three institutions issuing the degrees.</p><p>This Thesis is a part of the examination for the doctoral degree.</p><p>The invested degrees are official in Spain, the Netherlands and Sweden respectively.</p><p>SETS Joint Doctorate was awarded the Erasmus Mundus excellence label by the European Commission in year 2010, and the European Commission’s Education, Audiovisual and Culture Executive Agency, EACEA, has supported the funding of this programme</p><p>The EACEA is not to be held responsible for contents of the Thesis.”  QC 20170412</p>
168

Modélisation de causalité et diagnostic des systèmes complexes de grande dimension / Causality modeling and diagnosis of large-scale complex systems

Faghraoui, Ahmed 11 December 2013 (has links)
Cette thèse s'inscrit dans le cadre du projet européen PAPYRUS (7th FWP (Seventh Framework Program) et concerne le développement de modèles et d'outils permettant l'analyse d'un procédé industriel en interaction avec les indicateurs des performances du système. Ainsi que la synthèse d'algorithmes "Plug & Play" de diagnostic de défauts. Plus précisément, le premier objectif de la thèse est de proposer des modèles et des critères qui permettent, pour un procédé complexe de grande dimension, de savoir si des objectifs, exprimés en termes de performances (coût, de sûreté de fonctionnement, etc.), sont atteignables. Dans le cadre de la modélisation de causalité du système, une méthode, basée sur le transfert entropie, est proposée afin d'identifier le modèle de causalité du système à partir des données. On s'intéressera aussi à l'influence de divers défauts sur cette atteignabilité. Les outils utilisés sont principalement basés sur l'analyse par approche graphique (graphe de causalité) conjointement avec des outils statistiques. Le second objectif concerne la mise en oeuvre d'algorithmes de diagnostic de défauts. Une procédure hiérarchique de diagnostic de défauts s'appuyant sur les modèles de causalité du système est mise en oeuvre. Cette étape a aussi pour objectif de permettre l'évaluation des performances du système. La cible est le procédé d'application du projet PAPYRUS (papeterie Stora Enso d'IMATRA en Finlande) / This thesis is part of the European project PAPYRUS (7th FWP (Seventh Framework Program) and it concern the developments of models and tools for the analysis of an industrial process in interaction with system performance indicators. Thus, the developments of Plug & play algorithms for fault diagnosis. More specifically, the first objective of the thesis is to propose models and criteria, which allow, for large complex systems, whether the objectives expressed in terms of performance (cost, dependability, etc.) are achievable. Within the causality modeling system, a transfer entropy based method is proposed to identify the causality model of a system from data. We also focused on the influence of different faults on system performance reachability. The tools used are mainly based on graphical approach analysis in parallel with statistical tools. The second objective concerns the implementation of algorithms for faults diagnosis. A hierarchical fault diagnosis process based on causality model of the system is implemented. This step also allows the evaluation of the system performance. We applied our methods on the PAPYRUS project plant (board machine Stora Enso IMATRA in Finland)
169

Kundtjänster för mobilapplikationer : Utveckling av rapportgenerator, symbolgenerator,RevitArchitecture–add-in och metadatahantering / Custumer Services for Mobile Application

Bernau, Maja, Olsson, Tobias January 2014 (has links)
The goal of this project was to streamline and automate a business system. This was achieved through the implementation of four subtasks. This report describes what parts of the system that needed to be updated and why. It also describes how the development was carried out and what results the project ultimately led to.   The project's tasks were to: Create a report generator designed to generate Excel documents. Develop a symbol generator where a user, through a web-based interface, could generate symbols. The symbols could then be used in the company's mobile application. Create an interface for a web service, and to develop an add-in for the modeling software Revit Architecture 2014. / Målet med detta projekt var att effektivisera och automatisera ett företagssystem. Detta skulle uppnås genom implementationen av fyra deluppgifter. Denna rapport beskriver vilka delar av systemet som behövde utvecklas och varför. Den beskriver även hur utvecklingen genomfördes samt vilka resultat projektet slutligen ledde till.   Projektets deluppgifter var att: Skapa en rapportgenerator för generering av Excel-dokument. Utveckla en symbolgenerator där man genom ett web-baserat gränssnitt kunde generera symboler avsedda att användas i företagets mobila applikation. Skapa ett gränssnitt för en web-tjänst samt utveckla ett add-in till modelleringsprogrammet Revit Architecture 2014.
170

Webclipse – Rich Internet Applications auf Grundlage serverseitiger Plugins

Lorz, Alexander, Peukert, Eric, Moncsek, Andy 23 April 2014 (has links) (PDF)
No description available.

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