This dissertation aims to explore how one could leverage Software Defined Network (SDN) and Network Function Virtualization (NFV) principles in order to realize Service Function Chaining (SFC) in a network. SDN is a new networking paradigm, which makes a network programmable through the use of a software entity called SDN controller. NFV is intended to enable deployment of virtualized network functions, therefore replacing existing hardware solutions. SFC provides the ability to route user traffic to one or more network functions in an orderly manner. SFC will potentially enable many use cases such as data providers being able to dynamically steer user traffic through a set of network functions such as rewall and loadbalancer. This study is based on a set of goals. These goals evolve around the implementation of a prototype that will enable a SDN controller to steer user traffic through a series of virtualized network functions (VNFs). An important part of the prototype setup is a Network Management Software (NMS) named BECS, which is developed by Packetfront Software AB. BECS is acting as an orchestrator on the network and has complete awareness of all the network devices present on the network it manages. One of the main requirements of the prototype is to enable BECS to communicate with a SDN controller. Once that has been achieved, BECS could provide the necessary information that the controller needs in order to create and install a set of forwarding rules in the SDN enabled switches of the network. All those steps are necessary in order to achieve SFC. In this prototype, SFC is realized by demonstrating the user specific traffic steering through a set of VNFs in a specific order, based on control messages originated from BECS. Until now, network architecture has been limited to the capabilities of the actual hardware equipment. SDN and NFV help us to overcome this limitation. Information needs to be available anywhere and at any time, in a reliable and secure way. To ensure that, we propose a new scheme of network architecture through our prototype solution. This solution intends to give the ability to network managers to re-shape their networks based on their needs by the use of SFC. / Denna avhandling syftar till att undersöka hur man kan utnyttja principer för Software Defined Network (SDN) och Network Function Virtualization (NFV) för att förverkliga Service Function Chaining (SFC) i ett nätverk. SDN är en ny typ av nätverksparadigm som gör ett nätverk programmerbart genom användning av en programvaruenhet som kallas SDN controller. NFV syftar till att möjliggöra utbyggnaden av virtualiserade nätverksfunktioner och på så sätt ersätta befintliga hårdvarulösningar. SFC bidrar till en förmåga att dirigera trafiken till en eller flera nätverksfunktioner på ett ordnat sätt. SFC kommer potentiellt att möjliggöra många användningsområden, t.ex. uppgiftslämnare som dynamiskt kommer kunna styra användartrafik genom en uppsättning av nätverksfunktioner såsom firewall och loadbalancer. Studien är baserad på en uppsättning av mål. Dessa mål kretsar kring genomförandet av en prototyp som gör det möjligt för en SDN-styrenhet att styra användartrafik genom en serie av virtualiserade nätverksfunktioner (VNFs). En viktig del av prototypinstallationen ar en Network Management Software (NMS) som heter BECS, vilken är utvecklad av Packetfront Software AB. BECS agerar som en Orchestrator på nätet och har fullständig kännedom om alla nätverksenheter som finns i nätverket som den förvaltar. Ett av de viktigaste kraven for prototypen är att göra det möjligt for BECS att kommunicera med en SDN controller. När detta uppnåtts kunde BECS lämna nödvändiga uppgifter som styrenheten behöver for att kunna skapa och installera en uppsattning vidarebefordrade regler iSDN-aktiverade switchar pa natet. Alla dessa åtgarder är nödvändiga for att uppnå SFC. I denna prototyp realiseras SFC genom att påvisa den användarspecifika trafikstyrningen genom en uppsättning VNFs i en viss ordning, vilket baseras på styrmeddelanden som härstammar fran BECS. Fram till nu har nätverksarkitektur varit begränsad till förmågan hos den faktiska hårdvaruutrustningen. SDN och NFV hjalper oss att undvika denna begränsning. Information måste finnas tillgänglig överallt och när som helst på ett tillförlitligt och säkert sätt. For att säkerställa detta föreslår vi med hjälp av vår prototyplösning ett nytt system for nätverksarkitektur. Denna lösning har för avsikt att ge network managers en förmåga att omforma sina nät baserat på deras behov av SFC-anvandning.

This report presents the results and findings gathered during the master thesis work performed by Madeleine Jareblom at Scania CV AB in Södertälje. Scania is a developer and manufacturer of trucks and buses. They always strive to improve their testing and simulations for current and future products.  In order to predict the outcome or to analyse the performance of components or systems, simulation models are a powerful tool to use. Realistic and adaptive models are of great interest for Scania and this thesis will cover a steering system performance simulation capability. A steering system consist of a hand wheel, steering gear and linkages down to the steering wheels. The purpose of a steering gear is to ease the resistance a driver has to apply in order to steer the wheels.  There are a lot of different steering systems that are being used in vehicles these days but one of the more common ones is Electric Hydraulic Power Steering (EHPS) which this paper will cover. The simulation model is of an open loop design for an EHPS system that takes input data and divide them into separate calculation blocks. Static variables and data from vehicle measurements were used, together with some assumptions such as; front wheel steering, only applicable for trucks, no roll inclination, 2- or 3-axel vehicles and some static angels in the suspension geometry. During the construction phase of the model, calibrations were performed and there it was found that the friction in the system was load dependent. When the model was calibrated the final output results consisted of; calculated trajectory of the vehicle, the required output torque from the steering gear, input and output power of the steering system together with the consumed energy. From the results of the trajectory output it could be seen that the model is sensitive to small deviations of the handwheel angle and possible road banking. This entailed that the calculated trajectory did not resemble the driven path gathered from vehicle test data. The calculated output torque from the model, was validated with the use of measured pressure and supplier specifications for the steering gear. The results indicated that the calculation model could capture torques from the steering gear close to reality. It could be concluded that the model could be used to describe resulting torques, output and input power together with the consumed energy.

Yes / An experimental study of wheel movement arising from compliance in the front suspension and steering system of a passenger car during braking is presented. Using a Kinematic and Compliance (K&C) test rig, movement of the front wheels and the suspension sub-frame, together with corresponding changes in suspension / steering geometry under simulated braking conditions, were measured and compared with dynamic measurements of the centre points of the front wheels. The resulting knowledge of front wheel deflections has enabled the causes and effects of steering drift during braking to be better understood in the design of front suspension systems for vehicle stability.

Yes / The fundamentals and preliminary analyses of an innovative future technology referred to as `semi-active steering' (SAS) are presented in this article. The proposed steering system configuration is similar to a conventional electrical power-assisted steering with the replacement of the rigid steering shaft with a low stiffness resilient shaft (LSRS), the presence of which allows `active control¿ to be performed on vehicles similar to the concept of full steer-by-wire (SBW). But, unlike SBW, the LSRS is an integral part of the system characteristics. The advantages of the semi-active system in comparison with SBWand other conventional systems are demonstrated. A mathematical model to predict the mechanical properties of the LSRS has been developed, and experiments were conducted on a medium-sized car fitted with an LSRS to verify that vehicle stability and drivability can be ensured in the event of active system failure. The results have indicated that the vehicle was stable and safe to be driven at low speeds, and is predicted to be driveable and safe at higher speeds. It is concluded that an SAS system of this type has the potential to improve the safety of SBW systems.

The aim of this master thesis is the construction of a steering system for Formula Student monopost. The main part of the thesis is the design and analysis of steering column using universal joints. The thesis also contains design and analysis of steering rack together with experimental measurement of steering column torsional stiffness. An important part of the thesis is also a calculation of steering forces.

International Telemetering Conference Proceedings / October 18-21, 2004 / Town & Country Resort, San Diego, California / This paper describes a flexible telemetry data link developed by National Nuclear Safety Administration’s Kansas City Plant (NNSA-KCP) and the University of Kansas (KU) in support of NNSA’s Remote Sensing Laboratory (NNSA-RSL) located at the Nevada Test Site. This data link is based on a beam steerable phased array antenna (PAA). The paper describes the PAA and the Airborne Measurement System (AMS) application requiring signal source tracking. It highlights flight test data collected during recent flight testing on the Nevada Test Site for the AMS.

ITC/USA 2010 Conference Proceedings / The Forty-Sixth Annual International Telemetering Conference and Technical Exhibition / October 25-28, 2010 / Town and Country Resort & Convention Center, San Diego, California / Direct spatial antenna modulation (DSAM) is a new approach to phased array control that opens up new "smart antenna" architecture possibilities. The DSAM technique leverages the inherent spatial differences of excitation in an antenna in a novel way to achieve the equivalent of conventional modulation and beam control effects. Smart antenna techniques are of potentially increasing importance to test range operations given a trend toward more flexible, internetworked, and autonomous test activities. The DSAM technique has been demonstrated through several generations of analysis, simulation, and prototyping, but has previously only been applied to narrowband antenna designs. Furthermore, the IQ DSAM approach in particular has not been previously implemented in hardware. This paper details the application of IQ DSAM to achieve wideband phase control using a commercial off the shelf (COTS) antenna. The phase control performance of IQ DSAM over a range of 1.5 GHz to 4 GHz is measured across relative field control angles of +/- 45 degrees. The measured IQ DSAM performance is compared to what could be expected from a conventional phased array element control architecture.

ITC/USA 2009 Conference Proceedings / The Forty-Fifth Annual International Telemetering Conference and Technical Exhibition / October 26-29, 2009 / Riviera Hotel & Convention Center, Las Vegas, Nevada / New technologies are sought to meet the requirements of evolving telemetry capabilities such as new operating bands, increased test article and ground segment collaboration, and on-the-fly quality of service (QOS) management. Smart antennas may contribute to this evolution by directing signal energy where and when it is needed. Direct spatial antenna modulation (DSAM) represents a new approach to cost-effective smart antennas potentially offering benefits such as post-amplifier modulation, polarization reconfigurability, phase-shifterless phased arrays, oscillator-less frequency conversion, and pre-receiver processing gain. The basic DSAM approach has recently been proven through analysis, simulation, and prototyping, with significant implications for future capabilities.

Parmi les méthodes les plus utilisées en inspection embarquée des structures (Structural Health Monitoring ou SHM), les techniques d’imagerie basées sur un modèle de propagation sont de plus en plus répandues. Pour les techniques d'imagerie basées sur un modèle de propagation, bien que ces techniques montent en popularité, la complexité des matériaux composites réduit grandement leur performance en détection d'endommagements comparativement aux démonstrations précédentes de leur potentiel sur des matériaux isotropes. Cette limitation dépend entre autres des hypothèses simplificatrices souvent posées dans les modèles utilisés et peut entraîner une augmentation des faux positifs et une réduction de la capacité de ces techniques à détecter des endommagements. Afin de permettre aux techniques d'imagerie basées sur un modèle d'offrir une performance équivalente à celle obtenue précédemment sur les structures métalliques, il est nécessaire d'exploiter des modèles de propagation considérant la dynamique complexe des ondes dans ce type de structures. Cette thèse présente les travaux effectués sur la modélisation de la propagation des ondes guidées dans les matériaux composites. En première partie, une amélioration simple des modèles de génération et de propagation est proposée afin de permettre de mieux reconstruire les signaux générés et propagés sur une structure composite. Par la suite, le potentiel de la technique « Excitelet » à détecter et positionner adéquatement un ou plusieurs endommagements sur un matériau, peu importe son empilement (d’un composite unidirectionnel à un matériau isotrope), est démontré tant pour le mode A[indice inférieur 0] que le mode S[indice inférieur 0]. Les résultats obtenus numériquement et expérimentalement démontrent une corrélation directe entre l'amélioration des modèles mathématiques derrière les techniques d'imagerie et la robustesse des techniques pour ce qui est de la précision sur le positionnement du dommage et du niveau de corrélation obtenu. Parmi les améliorations à la technique d'imagerie « Excitelet » proposées, une amélioration significative des résultats en imagerie est démontrée en considérant la distribution de cisaillement plan sous l’émetteur, ce qui est une nouveauté par rapport aux travaux de recherche précédents en imagerie. La performance de la technique d'imagerie via la modélisation de la propagation d'ondes guidées dans les laminés multicouches transverses isotropes est par la suite démontrée. Les équations de l'élasticité en 3D sont utilisées pour bien modéliser le comportement dispersif des ondes dans les composites, et cette formulation est par la suite implantée dans la technique d'imagerie « Excitelet ». Les résultats démontrent que l'utilisation d'une formulation mathématique plus avancée permet d'augmenter la précision quant au positionnement des dommages et à l'amplitude de la corrélation obtenue lors de la détection d'un dommage. Une analyse exhaustive de la sensibilité de la technique d’imagerie et de la propagation d’ondes aux conditions environnementales et à la présence de revêtement sur la structure est présentée en dernière partie. Les résultats obtenus montrent que la considération de la propagation complexe dans la formulation d’imagerie ainsi que la caractérisation des propriétés mécaniques « a priori » de l’imagerie améliorent la robustesse de la technique et confèrent à la technique « Excitelet » la capacité de détecter et positionner précisément un endommagement, peu importe le type de structure.

In this paper, we present the results of the design and fabrication of a 12 channel nano-membrane-based optical phased array that allows for large angle beam steering operating at wavelength=1.55µm. Our device is fabricated on silicon-on-insulator using standard CMOS process. By implementing unequally spaced waveguide array elements, we can relax the half-wavelength spacing requirement for large angle beam steering, thereby avoiding the optical coupling between adjacent waveguides and reducing the side-lobe-level of the array radiation pattern. 1D beam steering of tranverse-electric polarized single mode light is designed to be achieved thermo-optically through the use of thin film metal phase shifters. / text