Dissertations / Theses: 'Controller SDN'

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Liu, Lida. "Hardware-Efficient WDM/SDM Network : Smart Resource Allocation with SDN Controller." Thesis, KTH, Kommunikationssystem, CoS, 2019. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-261155.

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Optical networking has been developing for decades and wavelength-division multiplexing (WDM) is the main technology used to carry signals in fiber-optical communication systems. However, its development has slowed because it is approaching the Shannon limit of nonlinear fiber transmission. Researchers are looking for multi dimensional multiplexing. Space-division multiplexing (SDM) is an ideal way to scale network capacities. The capacity of WDM/SDM network could be expanded to several times the capacity of WDM network but the active hardware devices may also increase by several times. This project aims to answer a practical question: How to construct a WDM/SDM network with less hardware resource? There is no mature research about WDM/SDM network yet. Therefore, the problem can be divided into two parts: (1) how to build a WDM/SDM network and (2) how to allocate resource and compute routes in such a network to minimize hardware resources. First, this thesis proposes a WDM/SDM node which has bypass connections between different fibers and architecture on demand (AoD) to effectively decrease the number of active hardware devices within the node. Then, two types of networks were constructed: one with bypass connections in each node and another one without any bypass connections. These networks were under the control of a software defined network (SDN) controller. The controller knew the wavelength resources within the networks. Several algorithms were applied to these networks to evaluate the effect of a bypass network and to identify the desired characteristics (to find short length path and decrease the probability of spectrum fragmentation) of an algorithm suitable for a network with bypass connections. The results of applying the proposed algorithms in two networks proved that the bypass connections increased the blocking probability in small topology but did not affect the results in large topology. The results in a large-scale network with bypass network were almost the same as the results in a network without bypass connections. Thus, bypass connections are suitable for large-scale network.
Optiskt nätverk har utvecklats i årtionden och våglängdsdelningsmultiplexering (WDM) är den viktigaste tekniken som används för att bära signaler i fiberoptiska kommunikationssystem. Utvecklingen har dock minskat eftersom den närmar sig Shannon-gränsen för olinjär fiberöverföring. Forskare letar efter flerdimensionell multiplexering. Space-division multiplexing (SDM) är ett idealiskt sätt att skala nätverkskapacitet. Kapaciteten för WDM / SDM-nätverk kan utökas till flera gånger WDM-nätverkets kapacitet, men de aktiva hårdvaraenheterna kan också öka med flera gånger. Projektet syftar till att svara på en praktisk fråga: Hur konstruerar jag ett WDM / SDM-nätverk med mindre hårdvara? Det finns ingen mogen forskning om WDM / SDM-nätverk än. Därför kan problemet delas in i två delar: (1) hur man bygger ett WDM / SDM-nätverk och (2) hur man fördelar resurser och beräknar rutter i ett sådant nätverk för att minimera hårdvaruressurser. Först föreslår denna avhandling en WDM / SDM-nod som har förbikopplingsanslutningar mellan olika fibrer och arkitektur på begäran (AoD) för att effektivt minska antalet aktiva hårdvaraenheter inom noden. Sedan konstruerades två typer av nätverk: en med bypass-anslutningar i varje nod och en annan utan några bypass-anslutningar. Dessa nätverk kontrollerades av en mjukvarudefinierad nätverkskontroller (SDN). Styrenheten visste våglängdsresurserna i nätverket. Flera algoritmer applicerades på dessa nätverk för att utvärdera effekten av ett förbikopplingsnätverk och för att identifiera de önskade egenskaperna (för att hitta en kort längdväg och minska sannolikheten för spektrumfragmentering) av en algoritm som är lämplig för ett nätverk med bypass-anslutningar. Resultaten av att tillämpa de föreslagna algoritmerna i två nät visade att förbikopplingsförbindelserna ökade blockeringssannolikheten i liten topologi men inte påverkade resultaten i stor topologi. Resultaten i ett storskaligt nätverk med bypass-nätverk var nästan samma som resultaten i ett nätverk utan bypass-anslutningar. Bypassanslutningar är således lämpliga för storskaliga nätverk.

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Kodzai, Carlton. "Impact of network security on SDN controller performance." Master's thesis, University of Cape Town, 2020. http://hdl.handle.net/11427/32514.

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Internet Protocol network architectures are gradually evolving from legacy flat networks to new modern software defined networking approaches. This evolution is crucial as it provides the ideal supporting network structure, architecture and framework that supports the technologies that are also evolving in software-based systems like Network Functions Virtualization (NFV). The connectivity requirements resulting from this paradigm shift in technology is being driven by new bandwidth requirements emanating from the huge number of new use cases from 5G networks and Internet of things (IoT) future technologies. Network security remains a key critical requirement of these new modern network architectures to deliver a highly available, reliable service and guaranteed quality of service. Unprotected networks will usually experience service interruptions and cases of system non-availability due to network attacks such as denial-of services and virus attacks which can render key network components unusable or totally unavailable. With the centralized approach of the Software Defined Networking architecture, the SDN controller becomes a key network point that is susceptible to internal and external attacks from hackers and many forms of network breaches. It being the heart of the SDN network makes it a single point of failure and it is crucial that the security of the controller is guaranteed to avoid unnecessary irrecoverable loss of valuable production time, data and money. The SDN controller design should be guided by a robust security policy framework with a very sound remedy and business continuity plan in the event of any form of a security attack. Security designs and research work in SDN controllers have been done with focus on achieving the most reliable and scalable platforms through self-healing and replication processes. In this dissertation the research that was done proposed a security solution for the SDN controller and evaluated the impact of the security solution on the overall SDN controller performance. As part of the research work literature review of the SDN controller and related technology carried out. The SDN controller interfaces were analyzed and the security threats that attack interfaces were explored. With link to a robust security framework a security solution was used in the experiments that analyzed the attacks from the external network sources which focused on securing the southbound interface by use of a netfilter with iptables firewall on the SDN controller. The SDN controller was subjected to denial service attack packets and the impact of the mitigation action observed on the SDN controller resources. Given that the network security layer introduced an additional overhead on the SDN controller's processors the security feature negatively affected the controller performance. The impact of the security overhead will inform on the future designs and possibly achieve a trade-off point between the level of security of the network and overall system performance due to security policies. The research analyzed and determined the performance impact of this crucial design aspect and how the additional loading due to network security affected the SDN controller normal operation.

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Brasini, Nicholas. "Analisi e sviluppo di un'interfaccia web per gestire controller SDN." Bachelor's thesis, Alma Mater Studiorum - Università di Bologna, 2017. http://amslaurea.unibo.it/14234/.

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Con il concetto di Software Defined Networking si intende un nuovo modo di concepire la struttura di una rete, ora divisa nel piano dei dati e nel piano di controllo, in modo da raggiungere un più preciso monitoraggio della stessa e garantire maggiore sicurezza, scalabilità e affidabilità. Questo lavoro di tesi ha come obiettivo la creazione di un'interfaccia web che permetta all'utente di poter iniziare ad utilizzare e a comprendere le potenzialità di una rete SDN. Tramite chiamate REST sarà possibile interagire con il controller, che rappresenta il cervello della rete stessa. Il progetto è stato pensato soprattutto per adattamenti futuri: in questo caso si è scelto di utilizzare il controller Ryu, ma il disaccoppiamento tra la parte html e la parte JavaScript permetterà in futuro di inserire ulteriori controller senza dover effettuare alcuna modifica strutturale.

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Mamushiane, Lusani. "Towards the development of an optimal SDN controller placement framework to expedite SDN deployment in emerging markets." Master's thesis, Faculty of Engineering and the Built Environment, 2019. http://hdl.handle.net/11427/30923.

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The challenge of poor broadband penetration in emerging markets is generally attributed to the high cost of deployment and operations for broadband infrastructure. Operators are more comfortable to rollout infrastructure in urban areas than in rural (i.e. remote, sparsely populated and low income) areas, due to the attractive profit margins they present. The repercussion of this is a wide “digital divide” between urban and rural areas, resulting in social and economic exclusion. The exclusion of rural areas stifles economic growth. In order to bridge this divide, a more cost effective telecommunication infrastructure is indispensable. This means adopting an architecture that minimizes both network deployment costs (CapEx) and operational costs (OpEx), while maintaining a high service quality level and ensuring business agility. There is a general consensus that a large portion of OpEx comes from the costs associated with the configuration and management of the telecommunication infrastructure. Software Defined Networking (SDN) has emerged as a promising solution to revolutionize network deployment, operations and economic growth. This paradigm aims to address management and configuration complexities in legacy networks so as to reduce the total cost associated with deploying and running telecommunication infrastructures. Conventionally, network control and data planes are tightly coupled and deployed within the same proprietary network device. SDN presents a shift in paradigm by decoupling the control plane from the data plane, abstracting lower level functionality of underlying hardware and enabling network programmability through a centralized controller. As the “brain” of the network, the controller must be able to process and respond to requests from the data plane promptly and proficiently. In order to optimize a controller’s operational efficiency, factors such as the number of controllers deployed, type of controller and controller placement are considered. During the network planning stage of an SDN deployment, the important questions that must be answered are: given a wide area network (WAN) topology, how many controllers are needed and where should they be placed to optimize SDN performance? Henceforth, this is referred to as the controller placement problem. This problem constitutes competing objectives such as load balancing, latency, reliability and CapEx, thus no single best placement solution is available. This study aims to address the controller placement problem by leveraging machine learning algorithms. Moreover, this study carries out a comparative performance evaluation of the most popular SDN controllers namely, Ryu, Floodlight, ONOS and OpenDayLight. The results from the performance evaluation are used to study the controller placement problem on an emulation orchestration platform. In order to contextualize the problem to emerging markets and maintain realism, a local national research and education wide area network called SANReN is used to test the proposed algorithms. This study can potentially be used by network operators as a guideline to start integrating SDN or plan a new SDN deployment, by helping them make quick automatic decisions regarding optimal controller placement.

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Bispo, Pedro José Neves. "A software defined network controller quantitative and qualitative analysis." Master's thesis, Universidade de Aveiro, 2017. http://hdl.handle.net/10773/23475.

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Mestrado em Engenharia Eletrónica e Telecomunicações
New challenges are being raised in the networking field with the increasing number of connected devices. The growth of mobile data usage has to be considered as a requirement for the deployment of future 5G networks, especially regarding mobility scenarios. Software-Defined Networking (SDN) enables a greater degree of dynamism and simplification for the deployment of those 5G networks. SDN provides the separation of the control plane from the forwarding plane, allowing more control, adaptability and cost reduction. The growth of SDN integration in new mechanisms and network architectures led to the development of different controller solutions, with a wide variety of characteristics. Several SDN controllers exist, which originated from the different needs of operators and research teams. That resulted in the development of their own controller versions, which made comparison efforts more difficult. As such, this work provides a wider study of several open-source controllers, (namely, OpenDaylight (ODL), Open Network Operative System (ONOS), Ryu and POX), by evaluating not only their performance, but also their characteristics in a qualitative way. Taking performance as a critical issue among SDN controllers, several criteria were evaluated by benchmarking the controllers under different operational conditions, using the Cbench tool. Results are presented regarding both qualitative and quantitative comparisons between those SDN controllers under test.
Com o aumento do número de dispositivos ligados em rede, surgem novos desafios no ramo das redes. A necessidade de acompanhar o crescimento da utilização de dados móveis é um dos requisitos a ter em conta nas futuras redes 5G (5a Geração), sobretudo em cenários de mobilidade. As redes controladas por software (do inglês, Software-Defined Networking (SDN)) permitem a simplificação e dinamismo necessários à criação das referidas redes 5G. As SDNs promovem ainda a separação do plano de controlo do plano de dados, permitindo um maior controlo, adaptabilidade e redução de custos. O crescimento da tecnologia SDN levou ao desenvolvimento de diferentes controladores, com diferentes características. Existem vários controladores SDN, com origem em diferentes necessidades dos operadores e equipas de investigação. Este desenvolvimento individualizado tornou as comparações entre os controladores mais difíceis. Deste modo, o trabalho desenvolvido fornece um estudo mais abrangente de vários controladores open-source (OpenDaylight (ODL), Open Network Operative System (ONOS), Ryu and POX), avaliando não só a sua performance como as suas características de uma forma qualitativa. Considerando a performance crucial nos controladores SDN, foram considerados vários critérios na avaliação dos controladores sob diferentes circunstâncias, utilizando a ferramenta Cbench. Os resultados apresentados são relativos à comparação qualitativa e quantitativa dos controladores em teste.

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Al-Mafrachi, Basheer Husham Ali. "Detection of DDoS Attacks against the SDN Controller using Statistical Approaches." Wright State University / OhioLINK, 2017. http://rave.ohiolink.edu/etdc/view?acc_num=wright1513738941473344.

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Biyase, Lindokuhle Zakithi. "Scalable Bandwidth Management in Software-Defined Networks." Master's thesis, Faculty of Engineering and the Built Environment, 2021. http://hdl.handle.net/11427/33656.

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There has been a growing demand to manage bandwidth as the network traffic increases. Network applications such as real time video streaming, voice over IP and video conferencing in IP networks has risen rapidly over the recently and is projected to continue in the future. These applications consume a lot of bandwidth resulting in increasing pressure on the networks. In dealing with such challenges, modern networks must be designed to be application sensitive and be able to offer Quality of Service (QoS) based on application requirements. Network paradigms such as Software Defined Networking (SDN) allows for direct network programmability to change the network behavior to suit the application needs in order to provide solutions to the challenge. In this dissertation, the objective is to research if SDN can provide scalable QoS requirements to a set of dynamic traffic flows. Methods are implemented to attain scalable bandwidth management to provide high QoS with SDN. Differentiated Services Code Point (DSCP) values and DSCP remarking with Meters are used to implement high QoS requirements such that bandwidth guarantee is provided to a selected set of traffic flows. The theoretical methodology is implemented for achieving QoS, experiments are conducted to validate and illustrate that QoS can be implemented in SDN, but it is unable to implement High QoS due to the lack of implementation for Meters with DSCP remarking. The research work presented in this dissertation aims at the identification and addressing the critical aspects related to the SDN based QoS provisioning using flow aggregation techniques. Several tests and demonstrations will be conducted by utilizing virtualization methods. The tests are aimed at supporting the proposed ideas and aims at creating an improved understanding of the practical SDN use cases and the challenges that emerge in virtualized environments. DiffServ Assured Forwarding is chosen as a QoS architecture for implementation. The bandwidth management scalability in SDN is proved based on throughput analysis by considering two conditions i.e 1) Per-flow QoS operation and 2) QoS by using DiffServ operation in the SDN environment with Ryu controller. The result shows that better performance QoS and bandwidth management is achieved using the QoS by DiffServ operation in SDN rather than the per-flow QoS operation.

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Barattini, Daniel. "Supporto a micro-servizi per controller SDN ad alta scalabilità e affidabilità." Master's thesis, Alma Mater Studiorum - Università di Bologna, 2020. http://amslaurea.unibo.it/21428/.

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L'attuale architettura di rete sta mostrando, nel tempo, un numero sempre più elevato di limiti derivanti principalmente dall'integrazione del piano di controllo e del piano di inoltro all'interno dei dispositivi di rete che la compongono. Uno dei più promettenti paradigmi che consente di superare queste limitazioni è SDN (Software-Defined Networking), che si basa sull'idea di estrarre il piano di controllo dai dispositivi di rete per inserirlo all'interno di un nuovo componente logicamente centralizzato: il controller SDN. Le attuali e più popolari implementazioni di controller SDN utilizzano però un’architettura monolitica che limita l’affidabilità e la scalabilità del sistema. L’obbiettivo di questa Tesi consiste quindi nell'implementazione di un prototipo di controller SDN che fornisca supporto a micro-servizi e nella sua relativa sperimentazione.

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Artuso, Matteo. "Controller SDN distribuiti basati su microservizi e orchestrati tramite Open Source MANO." Master's thesis, Alma Mater Studiorum - Università di Bologna, 2021.

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Questo lavoro si pone come obiettivo quello di studiare i microservizi che compongono un controller SDN come delle Virtualized Network Functions, impiegando Open Source Mano (OSM) come orchestratore. Nella fase iniziale viene studiata la procedura per definire e istanziare dei servizi di rete che soddisfino i requisiti richiesti ad un controller per le SDN. Viene poi approfondito l’aspetto del monitoring e della replicazione dei microservizi istanziati e funzionanti attraverso gli strumenti messi a disposizione dal sistema OSM. Viene infine testato il sistema attraverso l’impiego di una rete simulata, composta da una serie di switch che impiegherà il controller SDN scomposto.

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Vrablic, Pavol. "Simulace SDN sítě." Master's thesis, Vysoké učení technické v Brně. Fakulta elektrotechniky a komunikačních technologií, 2017. http://www.nusl.cz/ntk/nusl-317006.

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Dubovyi, Dmytro. "Návrh laboratorních úloh v oblasti programovatelnosti sítí." Master's thesis, Vysoké učení technické v Brně. Fakulta elektrotechniky a komunikačních technologií, 2020. http://www.nusl.cz/ntk/nusl-412995.

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The aim of the graduation thesis is to evaluate the current development in the field of SDN and the possibility of programmability of SDN elements using the application programming interface. The first theoretical chapter describes the following: the basic architecture of SDN, the traffic within SDN between its individual layers, the communication protocols Southbound interface and Northbound interface. The second chapter of the thesis deals with the programmability of SDN elements with the help of API. The third theoretical chapter describes the current development in the field of SDN. The practical part of the thesis is devoted to creation of two laboratory tasks dealing with the programming of the SDN API. Laboratory tasks include BIG-IP programming from F5 Network and routers from Arista Network. Programming is done using Python via REST API for BIG-IP, or eAPI for Arista EOS. The Ansible setup tool is also used for the same purpose.

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Pitzus, Antonio. "SDN : Software Defined Networking." Bachelor's thesis, Alma Mater Studiorum - Università di Bologna, 2017. http://amslaurea.unibo.it/14006/.

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In un periodo in cui tutto si evolve rapidamente, il settore delle telecomunicazioni sta assistendo alla crescita esponenziale del numero di dispositivi mobili costantemente connessi alla rete; ciò richiede la necessità di un nuovo modo di gestire le reti. La nuova visione che sta maturando in questi ultimi tempi è quella di adottare un modello di rete dinamico, flessibile e soprattutto affidabile e che non richieda grossi sforzi di manutenzione o l’installazione di ulteriori hardware da parte degli operatori. Una rete con queste caratteristiche può essere sviluppata grazie ad un modello architetturale innovativo come il Software Defined Networking (SDN) e ad un nuovo modo di sfruttare le funzionalità degli apparati di rete come la Network Function Virtualization (NFV), la quale è a sua volta un processo di virtualizzazione delle funzionalità di rete svolte da apparati di telecomunicazione fisici. Questi due concetti sono strettamente legati tra loro e possono comportare particolari vantaggi se applicati contemporaneamente, ma sono di per sè indipendenti. Software Defined Networking (SDN) è un’ architettura utilizzata per la realizzazione di reti di telecomunicazione nelle quali il piano di controllo della rete e quello del trasporto dei dati sono separati logicamente. La Network Function Virtualization (NFV) è il processo di virtualizzazione delle funzionalità di rete svolte da apparati di telecomunicazione fisici. Un ultimo aspetto da trattare riguarda la comunicazione del controller SDN di alto e basso livello. La comunicazione di alto livello, ovvero quella con i software applicativi è consentita grazie alle NBI (North-Bound Interfaces), mentre quella di basso livello, ovvero con i dispositivi hardware è consentita grazie alle SBI (South-Bound Interfaces). Queste due interfacce riescono a soddisfare le richieste del controller SDN grazie all' applicazione del paradigma Intent NBI, di tipo dichiarativo, non prescrittivo e indipendente dal fornitore.

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Schiavi, Daniele. "Software Defined Networks: analisi dell’interazione fra nodi di rete e Controller." Bachelor's thesis, Alma Mater Studiorum - Università di Bologna, 2017. http://amslaurea.unibo.it/14015/.

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L'obiettivo di questa tesi è verificare il comportamento e le interazioni tra uno switch e più controller, al variare del ruolo assunto da questi ultimi, in una rete virtuale SDN con protocollo OpenFlow. Nella tesi sono presenti tre capitoli, i primi due sono puramente teorici mentre il terzo descrive i test che sono stati effettuati. I primi due capitoli introducono e descrivono gli elementi principali di SDN ed OpenFlow, in particolare viene presentata l'architettura multi controller che è il tema fondamentale di questa tesi. Il terzo capitolo è il fulcro della tesi, descrive la topologia ed i test che sono stati effettuati per verificare il comportamento e le interazioni tra lo switch ed i controller.

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Liver, Toma, and Mohammed Darian. "Soft Migration from Traditional to Software Defined Networks." Thesis, Mälardalens högskola, Akademin för innovation, design och teknik, 2019. http://urn.kb.se/resolve?urn=urn:nbn:se:mdh:diva-44265.

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The concept of Software Defined Networking (SDN) may be a way to face the fast growing computer network infrastructure with its demands and requirements. The concept is attracting the interest of enterprises to expand their respective network infrastructures, but one has to consider the impacts of migrating from an existing network infrastructure to an SDN network. One way that could minimize the impacts is to proceed a soft migration from a traditional IP network to SDN, creating what is so called a heterogeneous network. Instead of fully replacing the network infrastructure and face the impacts of it, the idea of the soft migration is to replace a part of it with an environment of SDN and examine the performance of it. This thesis work will analyze the performance of a network consisting of a traditional IP network combined with SDN. It is essential during this work to identify the differences in performance when having a heterogeneous network in comparison with having a dedicated traditional IP network. Therefore, the questions that will be addressed during this thesis work is to examine how such a heterogeneous network can be designed and measure the performance of it in terms of throughput, jitter and packet losses. By the method of experimentation and the studying of related works of the SDN fundamentals, we hope to achieve our goals with this thesis work, to give us and the reader a clearer insight.

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van, 't Hof David M. "Service Provisioning in SDN using a Legacy Network Management System." Thesis, KTH, Skolan för informations- och kommunikationsteknik (ICT), 2016. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-204957.

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Software Defined Networking (SDN) has become increasingly popular in combination with Network Function Virtualization (NFV). SDN is a way to make a network more programmable and dynamic. However, in order to create a homogeneous network using this concept, legacy equipment will have to be substituted by SDN equipment, which is costly. To close the gap between the legacy world and SDN, we introduce the concept of a legacy Network Management System (NMS) that is connected to an SDN controller to perform service provisioning. This way, the NMS is capable of configuring both legacy as well as SDN networks to provide customers with the services that they have ordered, while still allowing for new SDN features in the SDN domain of the network. The main service we wish to provide using SDN is Service Function Chaining (SFC). Service provisioning consists of dynamically constructing a path through the ordered network services, in this case Virtual Network Functions (VNFs). This thesis focuses on the SDN controller and its interaction with the NMS. This project aims at configuring OpenFlow rules in the network using an SDN controller to perform SFC. Moreover, the focus will be on how to represent an SDN element and a service function chain in the legacy network NMS. The thesis also contains a discussion on what information should be exchanged between the management software and the controller. The management software used is called BECS, a system developed by Packetfront Software. Integrating SDN in BECS is done by creating a proof of concept, containing a full environment from the low level network elements to the NMS. By using a bottom-up approach for creating this proof of concept, the information that BECS is required to send to the SDN controller can be identified before designing and implementing the connection between these two entities. When sending the information, the NMS should be able to receive acknowledgement of successful information exchange or an error. However, when the proof of concept was created a problem arose on how to test and troubleshoot it. For this reason, a web Graphical User Interface (GUI) was created. This GUI shows the number of packets that have gone through a VNF. Because it is possible to see how many packets go through a VNF, one can see where a network issue occurs. The subsequent analysis investigates the impact of making such a GUI available for a network administrator and finds that the part of the network where the configuration error occurs can be narrowed down significantly.
Software Defined Networking (SDN) har blivit mer och mer populärt i kombination med Network Function Virtualization (NFV). SDN är en sätt för att göra ett nätverk mer programmerbart och dynamiskt. För att skapa ett homogent nätverk med detta koncept, behöver man dock ersätta traditionell utrustning med SDN utrustning som är dyr. För att stänga gapet mellan traditionella nätverk och SDN-världen, introducerar vi ett koncept med ett traditionell Network Management System (NMS) som är anslutet till en SDN-styrenhet för att utföra tjänsteprovisionering. På detta sätt kan NMS:et konfigurera både traditionella och SDN-nätverk, samt provisionera tjänster för kunderna medan nya SDN-funktioner möjliggörs i SDN-delen av nätverket. Den huvudsakliga tjänsten som vi vill lansera genom SDN är Service Function Chaining (SFC). Tjänsteprovisionering består av att konstruera en väg genom beställda tjänster, i detta fall Virtual Network Functions (VNFs). Detta examensarbete fokuserar huvusakligen på SDN-styrenheten och dess interaktion med NMS:et. Projektet syftar till att konfigurera OpenFlow regler i SDN-styrenheten för att utföra SFC. Dessutom fokuserar arbetet på hur man kan representera SDN-element och SFCs i ett traditionellt NMS. Vidare diskuteras vilken information som ska utbytas mellan NMS:et och SDNstyrenheten. NMS:et som ska vara användas är BECS, ett system utvecklat av Packetfront Software. Uppgiften löses genom att skapa ett proof of concept, som innehåller ett komplett system med alla komponenter från nätverkselement till NMS:et. Genom att använda en bottom-up-strategi för detta proof of concept kan informationen som BECS måste skicka till SDN styrenheten indentifieras, innan design och implementation av förbindelsen mellan enheterna kan utföras. När informationen är skickad ska NMS:et kunna hämta information om huruvida styrenheten fick informationen utan fel. Dock uppstår ett problem gällande hur man testar och felsöker detta proof of concept. Av denna anledning skapades ett web Graphical User Interface (GUI). Användargränssnittet visar antalet paket som går genom varje VNF, samt var i nätverket fel uppstår. Analysen undersöker hur stor effekten är för en nätverkadministrator och visar att området där fel kan uppstå begränsas avsevärt.

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Piska, Vojtěch. "Vývoj aplikací pro softwarově definované sítě." Master's thesis, Vysoké učení technické v Brně. Fakulta elektrotechniky a komunikačních technologií, 2016. http://www.nusl.cz/ntk/nusl-241990.

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In this diploma thesis is described new network architecture also known as software defined networks. In first part of work are explained and described tasks of individual architecture layers. Work includes discussion about advantages and disadvantages of these networks. In next part is described OpenFlow protocol which allows to controller communicate with underlying hardware devices. Last part contains proposal of laboratory excercises which demonstrate SDN technology.

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Frankeline, Tanyi. "Attack Modeling and Risk Assessments in Software Deﬁned networking (SDN)." Thesis, Linnéuniversitetet, Institutionen för datavetenskap och medieteknik (DM), 2019. http://urn.kb.se/resolve?urn=urn:nbn:se:lnu:diva-88806.

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Software Defined Networking (SDN) is a technology which provides a network architecture with three distinct layers that is, the application layer which is made up of SDN applications, the control layer which is made up of the controller and the data plane layer which is made up of switches. However, the exits different types of SDN architectures some of which are interconnected with the physical network. At the core of SDN, the control plane is physically and logically separated from the data plane. The controller is connected to the application layer through an interface known as the northbound interface and to the data plane through another interface known as the southbound interface. The centralized control plane uses APIs to communicate through the northbound and southbound interface with the application layer and the data plane layer respectively. By default, these APIs such as Restful and OpenFlow APIs do not implement security mechanisms like data encryption and authentication thus, this introduces new network security threats to the SDN architecture. This report presents a technique known as threat modeling in SDN. To achieve this technique, attack scenarios are created based on the OpenFlow SDN vulnerabilities. After which these vulnerabilities are defined as predicates or facts and rules, a framework known as multihost multistage vulnerability analysis (MulVAL) then takes these predicates and rules to produce a threat model known as attack graph. The attack graph is further used to performed quantitative risk analysis using a metric to depict the risks associated to the OpenFlow SDN model

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Valdinosi, Michele. "Utilizzo di un orchestratore per reti definite via software." Master's thesis, Alma Mater Studiorum - Università di Bologna, 2018. http://amslaurea.unibo.it/15855/.

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Nell'ultimo decennio il mondo delle Reti di Telecomunicazione ha avuto un'evoluzione accelerata, dovuta ai progressi del settore elettronico. I dispositivi hanno un ingombro sempre minore ed allo stesso tempo hanno mantenuto o addirittura aumentato la propria potenza di calcolo mentre calavano i costi di produzione ed acquisto (basti pensare ad un semplicissimo computer fisso degli anni 90 comparato ad uno smartphone dell'ultimo periodo, il quale ha una dimensione enormemente più piccola ed una potenza di calcolo maggiore). Il settore delle Reti di Telecomunicazioni si è quindi dovuto adattare al nuovo cambiamento ed ha subito una vera e propria rivoluzione dei propri paradigmi che ha dato luogo alla creazione di nuovi metodi per l'utilizzo delle reti. Esempi importantissimi di questi nuovi metodi sono il “Cloud Computing” ed il “Software-Defined Networking” (abbreviato normalmente in SDN). L'idea di utilizzare il Cloud Computing e l'SDN ha introdotto dei vantaggi, soprattutto dopo l'introduzione del Network Function Virtualization (NFV) che è il processo di virtualizzazione delle funzionalità di rete svolte da apparati di telecomunicazione fisici. Nell'elaborato andremo a dare una definizione più specifica del significato di Cloud Computing, SDN e NFV passando anche dal protocollo OpenFlow per poi introdurre e spiegare cos'è un Overarching Orchestrator per reti SDN. La parte finale riguarderà l'orchestrazione di reti Multi-Dominio, spiegando prima a cosa servono gli orchestratori di Dominio e Globali, e mostrando successivamente il funzionamento di un orchestratore globale tramite la sperimentazione di uno di questi sviluppato dal Politecnico di Torino chiamato Frog4.

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Elamin, Mohamed. "PERFORMANCE ANALYSIS OF SOFTWARE DEFINED NETWORKCONCEPTS IN NETWORKED EMBEDDED SYSTEMS." University of Akron / OhioLINK, 2017. http://rave.ohiolink.edu/etdc/view?acc_num=akron1497708739639971.

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Ponti, Luigi. "Virtualizzazione di funzioni di rete su piattaforme per cloud computing." Bachelor's thesis, Alma Mater Studiorum - Università di Bologna, 2015. http://amslaurea.unibo.it/9289/.

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Questo documento affronta le novità ed i vantaggi introdotti nel mondo delle reti di telecomunicazioni dai paradigmi di Software Defined Networking e Network Functions Virtualization, affrontandone prima gli aspetti teorici, per poi applicarne i concetti nella pratica, tramite casi di studio gradualmente più complessi. Tali innovazioni rappresentano un'evoluzione dell'architettura delle reti predisposte alla presenza di più utenti connessi alle risorse da esse offerte, trovando quindi applicazione soprattutto nell'emergente ambiente di Cloud Computing e realizzando in questo modo reti altamente dinamiche e programmabili, tramite la virtualizzazione dei servizi di rete richiesti per l'ottimizzazione dell'utilizzo di risorse. Motivo di tale lavoro è la ricerca di soluzioni ai problemi di staticità e dipendenza, dai fornitori dei nodi intermedi, della rete Internet, i maggiori ostacoli per lo sviluppo delle architetture Cloud. L'obiettivo principale dello studio presentato in questo documento è quello di valutare l'effettiva convenienza dell'applicazione di tali paradigmi nella creazione di reti, controllando in questo modo che le promesse di aumento di autonomia e dinamismo vengano rispettate. Tale scopo viene perseguito attraverso l'implementazione di entrambi i paradigmi SDN e NFV nelle sperimentazioni effettuate sulle reti di livello L2 ed L3 del modello OSI. Il risultato ottenuto da tali casi di studio è infine un'interessante conferma dei vantaggi presentati durante lo studio teorico delle innovazioni in analisi, rendendo esse una possibile soluzione futura alle problematiche attuali delle reti.

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Sonba, Ahmed, and Hassan Abdalkreim. "Performance Comparison Of the state of the art OpenFlow Controllers." Thesis, Högskolan i Halmstad, Akademin för informationsteknologi, 2014. http://urn.kb.se/resolve?urn=urn:nbn:se:hh:diva-27590.

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OpenFlow is a widely used protocol for software defined networks (SDNs) that presents a new paradigm in which the control plane is abstracted from the forwarding plane for the network devices. This approach differs from the conventional networking architecture, where both planes reside on the same networking device. In SDN approach centralized entities called “controllers” act like network operating systems run different applications that manage and control the network via well-defined APIs. OpenFlow switch is the forwarding plane in SDN architecture that has tables of packet-handling rules. Traffics passing the switch are compared against these rules and a match – action method is applied to the traffics. Depending on the rules installed by a controller application, an OpenFlow switch can act like a router, a switch, or a middle box without much caring about what kind of vendor to use in the network. Data centers’ networking is one of the applications that showed successful integration with OpenFlow protocol by making the network more consistent to the rapidly expanding number of virtual machines. But with the growing traffic in the data centers, the need for high controllers’ performance increases. Therefore, in this thesis we presented a performance evaluation in both throughput and latency perspectives for the current well-known OpenFlow controllers: NOX, Beacon, Floodlight, Maestro, OpenMul, and OpenIRIS. Controller benchmarking tool was implemented for incremental number of switches connected to the controller under test, and the results show that the OpenMul controller has the highest throughput, while OpenIRIS controller shows the lowest latency.

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Sanner, Jean-Michel. "Architecture du plan de contrôle SDN et placement des services réseaux dans les infrastructures des opérateurs." Thesis, Rennes 1, 2019. http://www.theses.fr/2019REN1S048/document.

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Le contexte de l'évolution des infrastructures des opérateurs de télécommunications vers les paradigmes SDN et NFV nécessite de lever différents verrous techniques, liés d'une part à la centralisation des fonctions de contrôle, d'autre part aux contraintes d'approches qui s'inspirent directement du Cloud Computing. Dans cette thèse, nous avons abordés deux problématiques. Dans la première nous cherchons à définir une architecture SDN plus adaptée et performante par rapport aux besoins des opérateurs. Pour cela, nous avons proposé un plan de contrôle SDN distribué et flexible visant à dépasser les limites du protocole OpenFlow centralisé ainsi que les contraintes de la virtualisation des fonctions réseaux. L'architecture proposée permet la composition, puis la validation et le déploiement différenciés de services réseaux composables et reconfigurables dynamiquement en prenant en compte les SLA associés aux services. Nous avons illustré certaines propriétés de cette architecture, distribution, composition, dynamicité dans une preuve de concepts. Dans la deuxième, pour réaliser les SLA attendus, nous cherchons à optimiser le placement des services réseaux dans cette infrastructure. Nous avons d'abord traité la problématique du placement de contrôleurs SDN en optimisant des métriques de latence, de charge et de fiabilité, puis de manière plus générale le placement de chaînes de fonctions réseaux virtualisées. Nous avons démontré pour cela les potentialités et les performances des algorithmes évolutionnaires pour tenter de proposer un outil de résolution générique de placement de fonctions réseaux
The evolution of telecommunications operators’ infrastructures towards the SDN and NFV paradigms requires to surmount various technical barriers. On one hand, it is necessary to deal with the centralization of control functions, and on the other hand with the constraints of approaches coming directly from Cloud Computing. In this thesis, we addressed two issues. Firstly, we tried to define a SDN architecture more suited to the requirement of operators. For this purpose, we proposed a distributed and flexible SDN control plane to overcome the limitations of the centralized OpenFlow protocol, as well as the constraints of network function virtualization. The proposed architecture allows for the differentiated composition, validation and deployment of dynamically reconfigurable network services, taking into account the SLAs associated with the services. We have illustrated some of its characteristics, namely, distribution, composition, dynamicity in a proof of concept. Secondly, to achieve the expected SLAs, we try to optimize the placement of network services in this infrastructure. We first dealt with the issue of SDN controllers placement seeking for the optimization of latency, load and reliability metrics. Then, we considered the placement of virtualized network functions chains. We have therefore demonstrated the potentialities and performances of evolutionary algorithms with the perspective to propose a generic resolution tool for placement of network functions

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Peixoto, Thiago Moratori. "Aumentando a resiliência em SDN quando o plano de controle se encontra sob ataque." Universidade Federal de Juiz de Fora (UFJF), 2017. https://repositorio.ufjf.br/jspui/handle/ufjf/6394.

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SDN (Software Defined Networks) é um paradigma de redes que permite aos operadores gerenciar os elementos de rede usando software que executa em um servidor externo sendo possível fazer a divisão do plano de controle e do plano de dados. Contudo, como em toda tecnologia, principalmente as mais incipientes, existem problemas de segurança e vulnerabilidades a serem investigadas. Por exemplo interrupções de rede causadas por erro humano. Um administrador que configura um controlador de maneira errada pode facilmente incorrer em diminuição de desempenho da rede, mesmo que o controlador funcione corretamente e não haja problemas com as regras. A esse cenário dá-se o nome de problema do administrador mal configurado, onde um administrador configura de maneira equivocada um controlador em plenas capacidades de maneira tal que prejudica o desempenho da rede. O trabalho proposto nessa dissertação tem dois objetivos: primeiro, avaliar o impacto no desempenho do plano de dados decorrentes de problemas causados por um sistema mal configurado; e segundo, propor, através do desenvolvimento de um módulo adjacente ao controlador, medidas para mitigar esses impactos. Os resultados obtidos por experimentação em um cenário realista mostram que a utilização desse módulo é capaz de melhorar o desempenho médio do sistema em 4,82%.
SDN (Software Defined Networks) is a network paradigm that allow operators to ma-nage network elements using software that executes on an external server making possible to divide the control plane from the data plane. However, as in all technologies, mainly the newer ones, there are security problems and vulnerabilities to be investigated. Network outages caused by human error for instance. An administrator that misconfigures a con-troller can easily reduce the network performance, even if the controller works properly and there are no errors with the installed rules. This scenario is also called the mis-configured administrator problem, where the administrator misconfigures a full capacity controller in a way that impairs the network performance. The work proposed in this dis-sertation has two objectives: first, to evaluate the impact on the performance of the data plan resulting from problems caused by a misconfigured system; And second, propose, through the development of a module adjacent to the controller, measures to mitigate these impacts. The results obtained by experimentation in a realistic scenario show that the use of this module is capable of improving the average performance of the system by 4,82%.

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Leoni, Elia. "Piano di controllo SDN per la composizione dinamica di funzioni di rete virtuali." Bachelor's thesis, Alma Mater Studiorum - Università di Bologna, 2016. http://amslaurea.unibo.it/10128/.

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Il documento analizza i vantaggi introdotti nel mondo delle telecomunicazioni dai paradigmi di Software Defined Networking e Network Functions Virtualization: questi nuovi approcci permettono di creare reti programmabili e dinamiche, mantenendo alte le prestazioni. L’obiettivo finale è quello di capire se tramite la generalizzazione del codice del controller SDN , il dispositivo programmabile che permette di gestire gli switch OpenFlow, e la virtualizzazione delle reti, si possa risolvere il problema dell’ossificazione della rete Internet.

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25

Renzi, Gianluca. "Controllo generalizzato via software di dispositivi per l'interconnessione flessibile di data center." Bachelor's thesis, Alma Mater Studiorum - Università di Bologna, 2015. http://amslaurea.unibo.it/8524/.

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Muench, David. "Gfi1-controlled transcriptional circuits in normal and malignant hematopoiesis." University of Cincinnati / OhioLINK, 2019. http://rave.ohiolink.edu/etdc/view?acc_num=ucin1553250015825734.

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Gong, Fei. "Front End Circuit Module Designs for A Digitally Controlled Channelized SDR Receiver Architecture." The Ohio State University, 2011. http://rave.ohiolink.edu/etdc/view?acc_num=osu1322606039.

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Nyberg, Tihmmy. "Introduktion till Software Defined Networking : Utvärdering av kontroller." Thesis, Mittuniversitetet, Institutionen för informationssystem och –teknologi, 2020. http://urn.kb.se/resolve?urn=urn:nbn:se:miun:diva-39380.

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Denna studie fokuserar på att samla information om Software Defined Networking, dess protokoll och dess kontroller. Det som jag har lärt mig under arbetet kommer att användas för att utvärdera två olika kontroller, POX och ONOS. Ett traditionellt nätverks kommer att sättas upp fysiskt och användas som en grund för att jämföra kontrollerna. Den traditionella lösningen använder två routrar och fyra switchar, och egenskaper som testas är bland annat lager 2 och lager 3 samt deras protokoll för redundans. Kontrollerna kommer sedan att användas för att se om de lever upp till samma krav. Resultaten av denna studie visar att varken POX eller ONOS kunde användas för varje testat scenario, inte med de moduler som kontrollerna kommer förinstallerade med. Det visade också att de egenskaper som de levde upp till var en hel del lättare att konfigurera och övervaka jämfört med dess traditionella motsvarigheter. Detta visar vikten av att lista ut vad som behövs och förväntas från nätverket innan man försöker hitta en passande lösning för att utföra detta. All information som samlats i denna studie används också för att skapa en laboration som ska introducera andra till koncepten kring SDN. Den undersöker hur Mininet kan användas för att virtualisera ett nätverk, hur flöden kan installeras med OpenFlow samt hur en kontroller kan användas för att förenkla administration av ett nätverk.
This study focuses on gathering information about Software Defined Networking, it's protocols ans it's controllers. What I have learned doing this will be used to evaluate two different controllers, POX and ONOS. A traditional network setup will be set up physically and serve as a base when it comes to comparing the controllers. The traditional setup includes two routers and four switches, and among the tested characteristics are layer 2 and 3 and it's redundancy protocols. The controllers will then be used to try and live up to the same characteristics. The result of this study shows that neither POX nor ONOS could be used for every scenario tested, not with the basic modules the controllers comes with. It also showed that the characteristics they did manage was a fair bit easier to setup and monitor compared to it's traditional counterparts, thus showing the importance of figuring out what is needed from a network before trying to find a fitting solution to how it needs to be set up. All the information gathered in this study is also used to create a lab instruction meant to introduce others to the concepts of SDN. It explores how to use Mininet to virtualise a network environment, how to install flows using OpenFlow and how to use a controller to simplify the management of the network.

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Fernlund, David, and Hofsten Erland von. "Controllerns förväntningar på sin rolls förändring : En fallstudie på en stadsbyggnadsförvaltning i Sverige." Thesis, Luleå tekniska universitet, Institutionen för ekonomi, teknik och samhälle, 2019. http://urn.kb.se/resolve?urn=urn:nbn:se:ltu:diva-74560.

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Studien hanterar vilka förväntningar controllers själva har på förändringen av deras roll genom att utföra en kvalitativ fallstudie av detta på en kommunal organisation i Sverige. Det i syfte att skapaen förståelse för controllerns egna förväntningar på förändringen av dess roll inom en kommunal förvaltning i Sverige, genom att analysera de förväntningar som existerar från controllern själv och deras ekonomichef. Sedan controllerrollen började bli vanlig i Sverige under 1970-talet har en vetenskaplig debatt förts kring ämnet angående controllers påverkan, roll och värde i organisationer med studier som även behandlar vinster och potentiella förluster av rollens förändring och hur förväntningar påverkar denna förändring. Därmed finns det anledning att vidarestudera controllers egna förväntningar för att öka förståelsen för detta fenomen och dess påverkan på controllerns roll. Denna studie undersökte controllers egna förväntningar på förändring genom att utföra semistrukturerade intervjuer utifrån en teoretisk referensram baserad på controllerns rollförändring av controllerns roll och förväntningar på controllers. Tre controllers och en ekonomichef intervjuades och intervjuerna spelades in och transkriberades för att sedan tolkas och analyseras. Controllers roller analyserades med hjälp av en figur för kategorisering av controllers och förväntningar genom djupgående analys av controllers svar kring förväntningar, roll och förändring. Studien har kommit fram till att controllers har förväntningar på att arbeta mot mindre hantering av statiska uppgifter och redovisning. Förväntningarna riktar sig även mot att föra närmare samarbeten med verksamheter, utföra analyser och vara delaktiga i projekt. Studien indikerar även att controllers själva kan vara en drivande faktor för denna förändring genom sina arbetsuppgifter och tillvägagångsval i utförandet av dessa. Controllers förväntningar stämmer även väl överens med de förväntningar som finns från Ekonomichef och ledning där ekonomichefen ger uttryck för ledningens förväntningar. Studien fördjupar kunskapen om controllers egna förväntningar och påverkan på sin roll genom att analysera deras förväntningar samt de som finns från ekonomichefen vilket förbättrar förståelsen av rollens förändring. Detta har implikationer för hur tillvägagångssätt av en medveten förändring eller utveckling av rollen bör utformas. Studien öppnar även för fortsatt forskning angående hur dessa förväntningar kan se ut i bland privata företag eller kvantitativa studier av controllers förväntningar.
The study deals with what expectations controllers themselves have in the change of their role by performing a qualitative case study of this phenomenon on a municipal organization in Sweden. The purpose of this study is to create an understanding of the controller's own expectations of the changes of their role within a municipal administration in Sweden, by analyzing the expectations that exist from the controllers themselves and their financial manager. The controller role emerged and became commonplace in Sweden during the 1970s, and an ongoing debate on the subject of the controller's influence, role and value within an organization has been present since, including studies that deal with gains and potential losses of the controller’s roles change and how accompanying expectations affect this change. Thus, there is reason to further study the controllers'own expectations in order to increase the understanding of this phenomenon and its impact. This study examined the controller’s own expectations on changes by conducting semi-structuredinterviews based on a theoretical frame of reference formed around the controller's role, changes in the role and expectations of surrounding the role. Three controllers and one chief financialofficer were interviewed in this study, these interviews were recorded and transcribed as to laterbe and analyzed. The controller’s roles were analyzed using a diagram for categorizing controllers, the expectations were then handled through in-depth analysis of controllers responses concerning expectations, role and change based on the conclusions of the controller's roles in the diagram. The study concluded that Controllers have expectations of working towards less management of statictasks and accounting in order to collaborate closer with businesses, carry out analyzes and beinvolved in projects. Expectations also aim to have closer collaboration with businesses, carrying out analyzes and participating in projects. The study also indicates that controllers themselves can be a driving force for this change through their work tasks and choice of approach in execution. Controller's expectations are also in line with the expectations of the chief financial officer and management with the chief financial officer acting as a conduit for management's expectations. The study expands the knowledge of controller’s own expectations and their influence on theirrole, which furthers the knowledge of the changes of the role. In turn this has implications for how a conscious approach to the change and development of the role ought to be designed. The study also enables continued research on how these expectations can manifest themselves among private companies and quantitative studies.

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D'Anniballe, Andrea. "Progettazione della sala di controllo missione della stazione di ricetrasmissione satellitare di Forlì." Bachelor's thesis, Alma Mater Studiorum - Università di Bologna, 2015. http://amslaurea.unibo.it/8593/.

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In questo lavoro di tesi si è voluto rappresentare, mediante l'utilizzo del software SolidWorks, quella che sarà la nuova stazione di ricetrasmissione satellitare di Forlì, già esistente presso il laboratorio di radioscienza ed esplorazione planetaria sotto il nome di Alma Mater Ground Station (AMGS), la quale lavorerà come sala di controllo missione nel nuovo progetto della European Space Agency (ESA), ovvero la missione ESEO, progetto educativo che vede il contributo di studenti provenienti da varie facoltà europee. È stato inizialmente ampliato il lavoro di tirocinio svolto dal candidato, il quale ha riguardato la rappresentazione in SolidWorks delle antenne che saranno utilizzate dalla stazione di ricetrasmissione e del loro futuro posizionamento, mediante uno studio strutturale dei tralicci che sosterranno le antenne, quindi ponendo attenzione al carico del vento al quale potrà essere sottoposta l'antenna parabolica del diametro di 3 metri. Successivamente è stato svolto uno studio generale dell'attrezzatura necessaria alla comunicazione satellitare,e quindi dell'interconnessione dei vari componenti. Quindi è stata disegnata in SolidWorks la sala di controllo missione, che sarà ubicata presso il nuovo tecnopolo che sorgerà nelle vicinanze della Scuola di ingegneria, il quale sarà sede del CIRI Aeronautica, Spazio e Mobilità di Forlì. Sono state importate le antenne, già disegnate nel lavoro di tirocinio, e sono stati disegnati i vari componenti e arredamenti della sala di controllo, disponendoli in modo tale da creare una visione vicina alla realtà.

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Junior, Rui Bertho. "Programação linear com controle de risco para o planejamento da operação do SIN." Universidade de São Paulo, 2013. http://www.teses.usp.br/teses/disponiveis/18/18154/tde-29042013-112650/.

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O planejamento da operação energética do sistema interligado nacional brasileiro é realizado por uma cadeia de modelos computacionais de otimização e simulação da operação. Entretanto, o risco de déficit, um importante indicador de segurança energética no setor elétrico, é tratado como uma variável de saída dos modelos computacionais. No planejamento de médio prazo é utilizado o software NEWAVE, que utiliza uma representação agregada em subsistemas equivalentes. Este trabalho propõe a implementação de um modelo de otimização linear para o planejamento da operação de médio prazo capaz de considerar o risco de déficit em sua formulação. Para o controle de risco de déficit, é proposta a utilização da métrica de risco conhecida por CVaR (Conditional Value at Risk), por se caracterizar como uma métrica de risco coerente, além de poder ser implementada por meio de um conjunto de restrições lineares.
The energetic operation planning of the Brazilian interconnected system is performed by a chain of computational models for the system optimization and simulation. However, the deficit risk, an important energy security indicator for the electric sector, is treated as an output variable on the computational models. In the medium-term of the energetic planning is used the software NEWAVE, which uses equivalent systems on aggregated representation. This work proposes the implementation of a linear optimization model for the medium-term of the energetic planning able to consider the deficit risk in its own formulation. To control the deficit risk is proposed the use of the risk metric known as CVaR (Conditional Value at Risk), because it is characterized as a coherent risk metric, and can be implemented through a set of linear constraints.

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Chapuis, Yves André. "Controle direct du couple d'une machine asynchrone par l'orientation de son flux statorique." Grenoble INPG, 1996. http://www.theses.fr/1996INPG0006.

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De part sa robustesse, la simplicité de sa structure, son poids et sa taille, la machine asynchrone offre de nouvelles perspectives technologiques dans de nombreux domaines industriels, où l'on apprécie principalement son peu de maintenance et son faible coût. Avec les progrès de l'électronique de puissance, liés à l'apparition de composants interrupteurs rapides, et le développement des technologies numériques de commande, câblées ou programmées, il est possible à présent, de choisir une structure de commande beaucoup plus évoluée. Ainsi, la commande vectorielle à flux rotorique orienté d'une machine à induction peut maintenant mettre en évidence des principes de contrôle du couple permettant d'obtenir des performances équivalentes à celles de la machine à courant continu. Cependant cette structure nécessite, en général, la mise en place de capteurs sur l'arbre pour la connaissance d'une grandeur mécanique. De plus elle reste très sensible aux variations de paramètres de la machine, notamment celles de la résistance rotorique. Le travail réalisé dans le cadre de cette thèse propose une alternative à ces problèmes de sensibilité. En effet, on présente ici une méthode dans laquelle les grandeurs de contrôle que sont le flux statorique et le couple électromagnétique, sont calculées à partir des seules grandeurs liées au stator et ceci sans l'intervention de capteurs mécaniques. Cette nouvelle structure de commande, couramment nommée : Contrôle Direct du Couple de la machine asynchrone (Direct Torque Control DTC), a été développée plus récemment. Pour l'étude de cette structure de commande, on a choisi de commencer par mettre en place, à partir des informations présentées dans les publications, un dispositif expérimental et un logiciel de simulation. Par la suite, on a développé et complété ces deux supports d'étude, en vue des travaux spécifiques que l'on s'est fixés. Pour thèse de ces travaux, on a décidé d'analyser les comportements de la commande dans une très large plage de vitesses. Pour cela, on s'est appuyé sur les conditions de fonctionnement d'applications précises, comme celles du véhicule électrique pour laquelle on a réalisé une étude complémentaire en simulation

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Bauer, Zachary Obenour. "A Calibration Method for a Controlled Reception Pattern Antenna and Software Defined Radio Configuration." Ohio University / OhioLINK, 2013. http://rave.ohiolink.edu/etdc/view?acc_num=ohiou1357402542.

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Glazar, Nikolaus. "Micropatterned Photoalignment for Wavefront Controlled Switchable Optical Devices." Kent State University / OhioLINK, 2016. http://rave.ohiolink.edu/etdc/view?acc_num=kent1460650961.

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Bouënard, Alexandre. "Synthesis of Music Performances: Virtual Character Animation as a Controller of Sound Synthesis." Phd thesis, Université de Bretagne Sud, 2009. http://tel.archives-ouvertes.fr/tel-00497292.

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Ces dernières années ont vu l'émergence de nom- breuses interfaces musicales ayant pour objectif principal d'offrir de nouvelles expériences instru- mentales. La spécification de telles interfaces met généralement en avant l'expertise des musiciens à appréhender des données sensorielles multiples et hétérogènes (visuelles, sonores et tactiles). Ces interfaces mettent ainsi en jeu le traitement de ces différentes données pour la conception de nouveaux modes d'interaction. Cette thèse s'intéresse plus spécifiquement à l'analyse, la modélisation ainsi que la synthèse de situations in- strumentales de percussion. Nous proposons ainsi un système permettant de synthétiser les retours vi- suel et sonore de performances de percussion, dans lesquelles un percussionniste virtuel contrôle des pro- cessus de synthèse sonore. L'étape d'analyse montre l'importance du contrôle de l'extrémité de la mailloche par des percussionnistes ex- perts jouant de la timbale. Cette analyse nécessite la capture préalable des gestes instrumentaux de dif- férents percussionnistes. Elle conduit à l'extraction de paramètres à partir des trajectoires extremité capturées pour diverses variations de jeu. Ces paramètres sont quantitativement évalués par leur capacité à représen- ter ces variations. Le système de synthèse proposé dans ce travail met en oeuvre l'animation physique d'un percussionniste virtuel capable de contrôler des processus de synthèse sonore. L'animation physique met en jeu un nouveau mode de contrôle du modèle physique par la seule spé- cification de la trajectoire extrémité de la mailloche. Ce mode de contrôle est particulièrement pertinent au re- gard de l'importance du contrôle de la mailloche mis en évidence dans l'analyse précédente. L'approche physique adoptée est de plus utilisée pour permettre l'interaction du percussionniste virtuel avec un modèle physique de timbale. En dernier lieu, le système proposé est utilisé dans une perspective de composition musicale. La con- struction de nouvelles situations instrumentales de percussion est réalisée grâce à la mise en oeuvre de partitions gestuelles. Celles-ci sont obtenues par l'assemblage et l'articulation d'unités gestuelles canoniques disponibles dans les données capturées. Cette approche est appliquée à la composition et la synthèse d'exercices de percussion, et evaluée qualitativement par un professeur de percussion.

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ANDERSON, KATHERINE E., RUSSELL D. EDGE, ABIGAIL J. HACKSTON, SHOBA MARAJ, MICHAL J. ROMANOWSKI, REED L. SEAMONS, Ben K. Sternberg, PHILIP J. STOKES, and SALLY M. THURNER. "CONTROLLED SOURCE AUDIO MAGNETO- TELLURIC (CSAMT) GEOPHYSICAL INVESTIGATION OF THE MIDDLE SAN PEDRO RIVER BASIN, SOUTHEASTERN ARIZONA." LASI Laboratory for Advanced Surface Imaging, The University of Arizona (Tucson, AZ), 2008. http://hdl.handle.net/10150/624625.

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Groundwater resources are essential to support the growing population of Benson as well as the agriculture, and wildlife throughout the Middle San Pedro Basin. A refined model of the hydrogeologic framework within the region is necessary to allow for the most efficient allocation of the area’s ground water resources by city planners and water managers in charge of future development. New data were collected by the University of Arizona’s Geophysics Field Camp to update and improve this representation. This survey utilizes Controlled Source Audio Magnetotellurics (CSAMT) to characterize previously unstudied locations in the San Pedro Basin. CSAMT data were processed and interpreted using software from Zonge Engineering and Interpex Ltd. Seven receiver stations along a five-kilometer Middle San Pedro transect were used to determine the resistivities of several basin-fill units. Results show some resistivity variability with respect to depth among the sampled regions. In the simplest representation of the data, four layers were modeled. Resistivities ranged from 15-30 ohm-m in the near-surface units. Deeper units showed resistivities of 5-10 ohm-m. These results were plotted to help identify conductive aquitard (clay) and potentially more resistive aquifer units. This clay unit could correspond to a thin unit of the St. David Formation, which has previously been identified as a confining unit between two separate basin aquifers. CSAMT data indicate that the local bedrock is deeper than 500 m.

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Ghostine, Rony. "Influence des fautes transitoires sur la fiabilité d'un système contrôlé en réseau." Thesis, Vandoeuvre-les-Nancy, INPL, 2008. http://www.theses.fr/2008INPL023N/document.

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Ce travail s'inscrit dans le cadre de l'évaluation de la sûreté de fonctionnement des systèmes commandés en réseau (SCR). La capacité des systèmes de commandes à compenser les effets de certaines défaillances de composants amène à redéfinir le concept de défaillances du système. La conséquence est que l'évaluation de la fiabilité prévisionnelle du système est dépendante de l'évaluation fonctionnelle et devient impossible avec les méthodes traditionnelles de la sûreté de fonctionnement. Pour surmonter ces difficultés, une approche basée sur la modélisation en vue de la simulation est proposée. Nous avons choisi les Réseaux d'activités stochastiques (SAN) largement connus dans la modélisation des protocoles de communication ainsi que dans les études de la sûreté de fonctionnement. Dans un premier temps, nous avons cherché à identifier l'incidence de deux types de défaillances fugitives : la perte d'un échantillon d'une part et le retard d'un échantillon dans la boucle de régulation d'autre part. Après, nous simulons le comportement en présence des deux types de perturbations simultanément, mettant en évidence des effets cumulatifs. Si on tient compte maintenant du fait que l'origine des pertes ou retards est due à la présence du réseau, il faut l'introduire dans le modèle. On introduit alors dans le modèle global du système la représentation SAN d'un réseau CAN et l'injection des défaillances dans celui-ci. La méthode de Monte Carlo est utilisée pour estimer les indicateurs de sûreté de fonctionnement et on montre l'influence de certains facteurs comme la charge du réseau par exemple. Nous avons proposé une méthode et les outils associés pour approcher cette évaluation par simulation et ainsi apporter une aide à la conception des systèmes satisfaisant à des exigences critiques sur certains paramètres de performance
Achieved work in this thesis deals with dependability evaluation of networked controlled system (NCS). The ability of control system to offset the effects of some components’ failure leads to redefine the concept of system failure. Consequently the reliability evaluation is dependent on functional parameters and becomes impossible with traditional dependability methods. This work aims at bringing a contribution relative to this aspect. To overcome these difficulties, an approach based on both modelling and simulation is proposed. We choose to work with stochastic activity network (SAN) widely used in modelling communication protocols as well as in dependability studies. First we sought to identify the incidence of two types of transient faults: loss of samples and delay within the control loop. Next we simulate the behaviour in the presence of two types of disturbances at the same time highlighting the cumulative effects. In fact the origin of the loss or delay information inside the control loop is due to the presence of the network, this aspect must be taken into account, that is why we introduce a new model representing the Controller Area Network (CAN) and injection of possible perturbations. Monte-Carlo method is used to estimate dependability parameters showing the influence of some factors such as network load for example. We have proposed a method and associated tools to approach this evaluation by simulation and thus provide assistance in designing systems to meet requirements on certain performance parameters

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Gaillard, Catherine. "Le gene alpha-tropomyosine chez xenopus laevis : organisation et etude de son controle transcriptionnel." Rennes 1, 1996. http://www.theses.fr/1996REN10152.

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L'objectif de ce travail a ete de caracteriser la structure du gene alpha-tm de xenope et d'etudier les modalites de son controle transcriptionnel au cours du developpement. L'analyse de deux clones genomiques nous a permis de montrer que la structure de la region 5' du gene etait conservee par rapport aux genes aviaires et mammiferes. Cette region possede deux promoteurs et le couple d'exons alternatifs 2a/2b. Nous avons montre que l'exon 2a etait specifiquement utilise dans les cellules musculaires lisse. Par une approche utilisant la pcr, nous avons etablit la structure partielle du gene et localise les exons 3 a 7 et 9a, 9b et 9d par homologie avec les genes tm des autres especes. Afin de determiner si le gene pouvait generer des isoformes specifiques du cerveau homologues a celles decrites chez le rat et le poulet, nous avons crible une banque d'adnc de cerveau. Aucun des clones isoles ne correspond aux isoformes decrites. La sequence de la region comprise entre les exons 9b et 9d ne revele pas la presence de l'exon 9c decrit chez les mammiferes et les aviaires. Mais un des clone isole code pour une nouvelle isoforme de tm. Nous avons montre que les deux promoteurs du gene etaient actives de maniere sequentielle au cours du developpement. Le promoteur interne qui genere les isoformes non musculaires est actif des le debut de l'ovogenese alors que le promoteur distal est silencieux. Le promoteur distal qui genere les isoformes musculaires est active des le stade 15 de l'embryogenese. Les arnm musculaires squelettiques sont localises dans les somites et le cur embryonnaire indiquant que le gene est un marqueur precoce des lignages musculaires squelettiques et cardiaques. Les arnm codant pour les isoformes de muscle lisse apparaissent plus tardivement au cours de l'embryogenese vers le stade 40. Par la technique de surexpression de genes dans des explants embryonnaires de blastula, nous avons montre que le gene pouvait etre active par les facteurs myogeniques de la famille myod et que les facteurs mef2 pouvaient moduler cette expression. Afin d'etudier le controle transcriptionnel du gene dans les cellules musculaires, nous avons construit un ensemble de genes chimeriques et analyse leur activite transcriptionnelle dans l'embryon et les cellules myogeniques de caille en culture. Nous avons defini un promoteur minimal musculaire qui correspond a la region de 285 nt en amont du site d'initiation de la transcription. Une analyse mutationnelle nous a permis de caracteriser quatre elements importants pour la transcription du gene dans les cellules musculaires, a savoir les boites e, c, m-cat, carg et une region riche en a/t

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Raibaud, Sophie. "Etude par RMN des deux fonctions de la protéine ribosomique bactérienne L20 : aspects structuraux de son rôle dans l'assemblage du ribosome et dans son autorégulation traductionnelle." Paris 6, 2003. http://www.theses.fr/2003PA066276.

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Muñoz, Hoyos José Rodrigo. "Síntese in situ pelo método Pechini de compósitos magnetoelétricos SBN/NFO para o controle do crescimento anormal dos grãos da fase SBN." Universidade Federal de São Carlos, 2016. https://repositorio.ufscar.br/handle/ufscar/8662.

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Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)
Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)
A study was made of the synthesis and processing of magnetoelectric particulate composites of strontium barium niobate (SrxBa1-xNb2O6, or simply SBN) as a lead-free piezoelectric phase and nickel ferrite (NFO) as a magnetic phase. The specific objectives of this work were: (i) to obtain SBN (TBT) and NFO phases without impurities during the synthesis of the powders and the densification of the ceramic bodies; (ii) to produce SBN-NFO composites of 0–3 connectivity, i.e., with a highly homogeneous distribution of ferrite phase in the SBN matrix; and (iii) to ensure mechanical interphase coupling based on high densification, without the occurrence of anomalous SBN grain growth. The Sr0.61Ba0.39Nb206/NiFe2O4 biphasic system (SBN61/NFO) was prepared with molar ratios of 50/50, 70/30 and 80/20 by means of in situ chemical synthesis using the Pechini method. The objectives of this work included an analysis and proposal of phase formation during the in situ synthesis of SBN/NFO grain growth, with high chemical homogeneity, a low degree of NFO phase percolation, and 0–3 connectivity. composites. The synthesized powders were analyzed by Rietveld refinement of their X-ray diffraction patterns. This enabled the quantification of spurious phases and revealed the effect of reducing these phases and the abnormal grain growth resulting from the increased proportion of NFO phase. However, the secondary phases could only be determined based on the hypotheses put forward in the proposal of the phase formation model of the SBN/NFO system. This proposed phase formation model enabled us to understand why SBN and NFO phases can be formed simultaneously during in situ synthesis by the Pechini method, and also to conclude that the presence of precipitates during the formation of the polymeric resin may be the cause of spurious phases. This allowed us to propose changes in the synthesis step in order to eliminate possible precipitates, which actually resulted in the reduction of the secondary phases in the tests of the 70/30 system. After sintering, magnetoelectric composites were obtained with a relative density of ~96%, without abnormal grain growth, with high chemical homogeneity, a low degree of NFO phase percolation, and 0–3 connectivity.
Neste trabalho estudou-se a síntese e o processamento de compósitos magnetoelétricos particulados de niobato de estrôncio e bário (SrxBa1- xNb2O6 ou, simplesmente, SBN), como fase piezoelétrica livre de chumbo, e de ferrita de níquel (NFO), como fase magnética. Os objetivos específicos do trabalho foram: obtenção das fases SBN (TBT) e NFO como únicas do sistema, tanto durante a síntese dos pós, quanto na densificação dos corpos cerâmicos; produção de compósitos SBN-NFO com conectividade 0-3, ou seja, com alta homogeneidade da distribuição da fase ferrita em uma matriz de SBN; e garantia do acoplamento mecânico entre as fases, a partir de alta densificação e sem a ocorrência de crescimento anormal de grãos da fase SBN. Neste trabalho adotou-se a síntese in situ pelo método Pechini para a preparação do sistema bifásico Sr0,61Ba0,39Nb206/NiFe2O4 (SBN/NFO), nas proporções molares 50/50, 70/30 e 80/20. Análise e proposta de formação de fases durante a síntese in situ de compósitos SBN/NFO foram incluídas nos objetivos deste trabalho. Os pós dos compósitos sintetizados foram analisados por refinamento estrutural dos perfis de difração de raios X, pelo método de Rietveld, o que permitiu evidenciar quantitativamente a presença de fases espúrias e o efeito de redução dessas fases, e do consequente crescimento anormal de grãos, pelo incremento da proporção da fase NFO. Contudo, a determinação das fases secundárias só pode ser concluída a partir das hipóteses levantadas na proposta do modelo de formação de fases desse sistema. Além disso, esse modelo permitiu explicar porque é possível a formação simultânea das fases SBN e NFO pela síntese Pechini in situ, e também concluir que a presença de precipitados na etapa de formação da resina polimérica poderia ser a causa da ocorrência das fases espúrias. Com isso, pode-se propor alterações na etapa de síntese, com a intenção de se eliminar possíveis precipitados, o que realmente resultou, para os ensaios realizados no sistema 70/30, em redução das fases secundárias e compósitos magnetoelétricos, após sinterização, com densidade relativa ~96%, sem crescimento anormal de grãos, de elevada homogeneidade química, com baixo grau de percolação da fase NFO e conectividade 0-3.
FAPESP: 2008/04025-0
FAPESP: 2012/24025-0
CAPES: Procad 2013 - 3012/2014

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Ferreyra, Tamara Lucía, Juan Quiroga, and Alicia Yemina Vega. "Controles de salud que se realizan los profesionales de enfermería." Bachelor's thesis, Universidad Nacional de Cuyo. Facultad de Ciencias Médicas. Escuela de Enfermería, 2017. http://bdigital.uncu.edu.ar/8626.

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Los profesionales de los hospitales, particularmente el personal de enfermería, están expuestos a una serie de riesgos, tales como: la exposición a agentes infecciosos, posturas inadecuadas, levantamiento de cargas durante la manipulación de los pacientes, desplazamientos múltiples, exposición a sustancias químicas irritantes, alergénicas y a radiaciones ionizantes, bien conocidos como productores de daños a la salud de los trabajadores. Es necesario que el personal se realice controles de salud y exámenes, tanto simples como complejos para prevenir enfermedades y, si existieran, limitar el daño. Ya que es necesario un personal de enfermería en óptimas condiciones de salud, para que este sea capaz de brindar una correcta atención de servicio a sus pacientes. Este trabajo de investigación tiene como objetivo establecer qué controles periódicos de salud, se realizan los profesionales de enfermería de los servicios de Cirugía, Ginecología y Neonatología del Hospital Alfredo Ítalo Perrupato en el primer semestre de 2016. Población y muestra de 60 enfermeros de dichos servicios los que respondieron un cuestionario con preguntas cerradas.
Fil: Ferreyra, Tamara Lucía. Universidad Nacional de Cuyo. Facultad de Ciencias Médicas. Escuela de Enfermería..
Fil: Quiroga, Juan. Universidad Nacional de Cuyo. Facultad de Ciencias Médicas. Escuela de Enfermería..
Fil: Vega, Alicia Yemina. Universidad Nacional de Cuyo. Facultad de Ciencias Médicas. Escuela de Enfermería..

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Tobin, Gros Christine. "Le dimorphisme sexuel du muscle levator ani du rat : la myogenese et son controle la testosterone." Paris 6, 1991. http://www.theses.fr/1991PA066365.

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Ce travail concerne l'etude de l'etablissement du dimorphisme sexuel (ds) du muscle levator ani (la) du rat. Le premier chapitre concerne la mise en evidence m. La chez la femelle adulte, l'etude de sa morphologie et de son innervation. Une etude quantitative a permis de montrer que le ds est lie a la difference importante du nombre et du calibre des fibres musculaires entre le male et la femelle. Le second chapitre concerne l'etude ultrastructurale du developpement perinatal (du 18eme jour de gestation au 12eme jour postnatal) du muscle la, dans les deux sexes. L'etablissement du ds se produit par la formation tres rapide des fibres musculaires chez le male au cours de la 1ere semaine postnatale. A g18, le muscle est constitue de myotubes primaires. Les premiers myotubes secondaires apparaissent a g21, le nombre de myotubes secondaires parait etre sous le controle de la testosterone. Dans le 3eme chapitre concerne l'etude de l'action de la testosterone sur le muscle la de la femelle. La testosterone stimule la formation des fibres musculaires, si le traitement est donne avant la fin de la premiere semaine postnatale. La testosterone augmente le calibre des fibres musculaires si le traitement est donne au-dela de la fin de la 1ere semaine postnatale. Chez la femelle adulte la testosterone, en plus de son action sur le calibre, stimule la proliferation des cellules satellites. De la fusion de ces cellules avec les fibres musculaires preexistantes, resulte une augmentation du nombre de noyaux

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Leoo, Malin. "Childhood obesity treatment during the first wave of the Covid-19 pandemic : – a retrospective controlled cohort study." Thesis, Örebro universitet, Institutionen för medicinska vetenskaper, 2021. http://urn.kb.se/resolve?urn=urn:nbn:se:oru:diva-91059.

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Abstract Introduction: Obesity amongst children is a major health problem. At the outpatient paediatric clinic at Södertälje hospital in Region Stockholm, there is a large and well-established treatment model against childhood obesity. During spring 2020 all elective care in Region Stockholm, including visits to the obesity team, was cancelled for 3 months due to relocation of health care professionals because of the Covid-19 pandemic. Aim: To investigate whether the first wave of the Covid-19 pandemic affected the outcome of childhood obesity treatment at one outpatient paediatric clinic in Region Stockholm. Methods: A retrospective controlled cohort study comparing two groups regarding results of first year of obesity treatment for children. One group had their first year of treatment during the first wave of the Covid-19 pandemic and the control group before the pandemic. Data was retrieved from BORIS and complemented by a review of medical records. Results: Mean change in BMI SDS after one year of treatment in the Covid group was -0.10 units and in the control group -0.11 (ns). In the Covid group more patients quit the treatment programme and had a smaller number of visits to a nurse compared to controls. Conclusion: This study showed no difference in outcome regarding change in BMI SDS. However, it seems that the cancellation of visits might have affected the number of children lost to follow-up. Therefore, clinics should consider “digi-physical” care (e.g., via telephone, videocalls or other media) to secure the child and parents motivation and participation in the obesity treatment programme.

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Sampaio, Rafael Coronel Bueno. "Sistemas de controle e nova arquitetura para diferencial eletrônico em veículos de passeio convencionais a combustão convertidos em veículos híbridos 4x4." Universidade de São Paulo, 2011. http://www.teses.usp.br/teses/disponiveis/18/18149/tde-05012012-161553/.

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Este trabalho apresenta três sistemas de controle distintos para a atuação em sistemas de tração elétrica traseira em veículos de passeio convencionais convertidos em VEHs (Veículos Elétricos Híbridos) 4x4, enfocando o desenvolvimento de um sistema diferencial eletrônico (SDE). As principais arquiteturas de veículos híbridos são apresentadas. O SDE, que atua em tempo de execução nas velocidades angulares dos pneumáticos traseiros em manobras variadas, depende dos sinais de esterçamento e aceleração impostos pelo condutor, considerando as modelagens cinemática e dinâmica do veiculo no cálculo dos valores de referência para o controlador. Controladores PID modificado, neurofuzzy baseado em inteligência artificial e um H-Infinito ótimo são projetados e detalhados. Uma nova arquitetura para o SDE é proposta e apresentada, visando a utilização de sistemas de controle robustos no problema do SDE, traçando-se um paralelo entre o seu desempenho e das arquiteturas convencionais quando o controlador H-Infinito ótimo assume o controle do SDE. O projeto e o desenvolvimento de um mini-VEH, a plataforma HELVIS (Hybrid ELectric Vehicle In low Scale), são apresentados. A implementação de um simulador veicular denominado HELVIS-SIM, inspirado na plataforma HELVIS, é também apresentada. O SDE, que compreende a arquitetura proposta e os controladores, são embarcados e também implementados no HELVIS-SIM. Resultados simulados obtidos no HELVIS-SIM são analisados. Testes experimentais do SDE na plataforma HELVIS são apresentados, considerando apenas testes de bancada sem o contato dos pneumáticos com o solo.
This work presents the development of three distinct control systems to rear electric traction control on conventional touring vehicles converted on 4WD (four-wheel drive) hybrid electric vehicles (HEVs), focusing on the design of a EDS (Electronic Differential System). Main HEV architectures are presented. The EDS controls the rear wheels angular speeds as the driver inputs steering and acceleration commands, considering both dynamic and kinematic models of the vehicle and so the actuators on the calculus of the desired rear angular speeds. One modied PID controller, one AI (Articial Intelligence) based controller and one robust optimal H \'infinite\' controller are designed and outlined. A new EDS architecture is proposed and presented, aimming the use of robust controllers to the EDS problem, comparing the use of the H \'infinite\' optimal controller to conventional EDS architectures. The design of a mini-HEV, the HELVIS (Hybrid ELectric Vehicle In low Scale) platform is also presented. The implementation of a parametric vehicular simulator, the HELVIS-SIM, is discussed. The EDS, which represents the controllers and the proposed architecture, is evaluated on the HELVIS platform and on the HELVIS-SIM. Simulated results are rst run in the HELVIS-SIM. Experimental results of the EDS tests are presented exclusively considering the evaluation on a bench test, without any contact of the platform with the pavement.

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Bizouarn, Tania. "Controle par le gradient de protons de l'affinite de l'atpase chloroplastique pour son substrat adp. Implications mecanistiques." Paris 11, 1991. http://www.theses.fr/1991PA112372.

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Le but de ce travail a consiste a etudier le mecanisme de couplage entre la synthese d'adp et le flux de protons par l'atpase chloroplastique membranaire. Nous avons mis au point une methode qui permet de garder constant le gradient de protons quand la concentration des substrats augmente, afin d'estimer des k#m de facon satisfaisante. Par cette methode, nous avons montre que: 1) le k#m pour l'adp depend de la concentration en phosphate et en magnesium; 2) il obeit a une loi complexe en fonction du delta-ph. Le k#m diminue legerement (k#m min. 6-7 microm), puis augmente fortement (30 microm et plus); 3) ces variations ne sont pas dues a une limitation de la diffusion de l'adp du cur de la solution vers les atpases; 4) il n'y a pas d'interaction specifique entre les transporteurs redox et les atpases; 5) le k#m pour l'adp et le v#m#a#x depend strictement du delta-ph et non du ph interne ou externe; 6) cette stricte delta-ph dependance du k#m et du v#m#a#x reflete soit un effet substrat soit un effet regulateur du gradient de proton sur la reaction. De plus, ceci suggere que la fixation des protons internes et le relargage des protons externes durant la catalyse est un processus concerte

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46

Medina, Yarza María Isabel. "Controle estrutural das ocorrências de ouro relacionadas a veios de quartzo na região de Mahoma (San José-Uruguai)." reponame:Biblioteca Digital de Teses e Dissertações da UFRGS, 2000. http://hdl.handle.net/10183/118556.

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A região de Mahoma (Dept. San José, Uruguay) é composta por três unidades litológicas principais: 1) Complexo Ortognáissico, 2) Complexo Metassedimentar e 3) Granitos tardi a pós-deformacionais que têm sido datados em 2000 Ma. As ocorrências de ouro estão relacionadas a veios de quartzo estruturalmente controlados e alojados nos granito-gnaisses do Complexo Ortognáissico. Assim, as ocorrências de ouro na região de Mahoma podem ser classificadas como veios de quartzo com Au (gold-quartz veins) em terrenos metamórficos. As principais ocorrências auríferas são: Mina Mahoma (Metagranodiorito Arroyo del Sauce, sin-deformacional) e Prospecto Área 13 (gnaisses proto a ultramiloníticos, Complexo Ortognáissico). As principais unidades litológicas da região de Mahoma registram a atuação de 4 eventos deformacionais, 3 dos quais têm caráter penetrativo e formaram as estruturas mais importantes do ponto de vista do controle de depósitos minerais. O evento D1 formou as principais rochas gnáissicas (S1, foliação milonítica), tanto no Complexo Ortognáissico, quanto no Complexo Metassedimentar. O evento D2 constitui uma foliação plano axial (S2), anastomosada, que parcialmente transpõe S1. O evento D3 é responsável pela estruturação final da região e é composto por um sistema de zonas de cisalhamento e dobras de arrasto. As ocorrências de Au e os veios de quartzo relacionados estão condicionados às zonas de cisalhamento (Mina de Mahoma) e à dobra flexural de arrasto (Prospecto Área 13). Dentro desse quadro estrutural, foi possível caracterizar os seguintes tipos de veios: a) veios paralelos à foliação milonítica S3 na ZCP (Zona de Cisalhamento Principal); b) veios oblíquos à foliação milonítica S3 (C e/ou R) na ZCP; c) veios perpendiculares à foliação milonítica S3 (T) na ZCP; d) veios em saddle reefs nas charneiras das dobras de arrasto F3. A paragênese metamórfica associada com a foliação milonítica S3 é composta por quartzo, plagioclásio, biotita, muscovita, esfeno, epidoto nas rochas gnáissicas ácidas (granito-gnaisses). A paragênese de alteração hidrotermal formada nas dilatâncias estruturais da fase D3 (sombras de pressão de porfiroclastos, fraturas Riedel transtrativas, rugosidades de foliações e de fraturas, aberturas na charneira de dobras flexurais) é composta por quartzo, clorita, carbonato, sericita, pirita, (albita?). As características estruturais e petrológicas da deformação D3 e do hidrotermalismo associado com os veios de quartzo e as ocorrências de Au sugerem um modelo metamórfico-hidrotermal para a origem das ocorrências de ouro associadas com veios de quartzo na região de Mahoma (Uruguay).
The Mahoma region (San José Dept., Uruguay) is formed by three major litological units: 1) Orthogneissic Complex, 2) Metasedimentary Complex, 3) Late- to post-deformational granites, which have been aged 2000 Ma. The gold occurrences are related to quartz veins, which are structurally controlled and emplaced in granite-gneisses of the Orthognaissic Complex. In this way, the gold deposits can be classfied as gold-quartz veins in metamorphic terrains. The main gold occurrences are: Mahoma Mine (sin-deformational Arroyo del Sauce Metagranodiorite) and Area 13 Target (proto to ultramilonitic gneisses, Orthogneissic Complex). The main lithological units of the Mahoma region show four deformational events; three of them are penetrative and developed the most important structures for ore deposits control. The D1 event developed the main gneiss rocks (S1, milonitic foliation), either in the Orthogneissic Complex, or in the Metasedimentary Complex. The D2 event developed an axial plane foliation (S2) with anastomosing pattern that transpose S1. The D3 event is responsible for the final organization of the region and developed a system of shear zones and related drag folds. The gold quartz veins ocurrences are structurally controlled by shear zones (Mahoma Mine) and the flexural drag fold (Area 13 Target). Based on structural analysis, it was possible to characterize the different type of gold-quartz veins: a) veins parallel to the S3 milonitic foliation in the ZCP (Principal Shear Zone); b) veins oblique to the S3 milonitic foliation (second order C and R Riedel fractures) in the ZCP; c) veins perpendicular to the S3 milonitic foliation (second order T fractures) in the ZCP; and d) saddle reefs veins in the F3 drag folds hinges. The metamorphic assemblage related to the S3 foliation is composed for quartz, plagioclase, biotite, muscovite, sphene, epidote in acidic gneiss rocks (granite-gneisses). The hydrothermal assemblage is composed by quartz, chlorite, carbonate, sericite, pyrite, (albite ?) and is placed in structural traps of D3 phase (pressure shadows of porphyroclast, Riedel transtensional fractures, foliations and fractures roughness, open spaces in flexural folds). The structural and petrological characteristics of the D3 deformation and the hydrothermal alteration associated with the ore veins suggest a metamorphic-hydrothermal model for the gold-quartz veins ocorrences in the Mahoma (Uruguay) region.

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47

Raehm, Laurence. "Controle electrochimique du mouvement d'une roue autour de son axe : de la molecule en solution a l'espece adsorbee." Université Louis Pasteur (Strasbourg) (1971-2008), 1999. http://www.theses.fr/1999STR13074.

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Les architectures moleculaires contenant des anneaux entrelaces ou des anneaux enfiles sur un fragment acyclique sont les precurseurs ideaux de machines moleculaires, c'est-a-dire de systemes dont certains elements peuvent etre mis en mouvement, de facon controlee, alors que d'autres restent immobiles. L'effet de matrice tridimensionnel du cu i a permis de synthetiser un rotaxane dont la roue contient un chelate bidentate et un chelate terdentate et dont le fil ne contient qu'un ligand bidentate. Le fil est substitue a ses extremites par des groupements encombrants. Des etudes de voltametrie cyclique ont permis de mettre en evidence le mouvement de rotation de l'anneau autour du fil moleculaire, en solution, lors du passage d'un degre d'oxydation du cuivre a un autre. Ces mouvements sont bien controles : les constantes de vitesse des mouvements de rearrangement ont ete determinees et sont de plusieurs ordres de grandeur plus elevees que dans tous les systemes precedemment etudies au laboratoire (glissement de deux anneaux, translation d'un macrocycle le long d'un fil). L'ancrage d'especes electroactives dont on pourrait induire la mise en mouvement a la surface d'une electrode a egalement ete etudie. Un mouvement de rearrangement autour du cuivre a ete observe au sein d'un film polymere conducteur electronique de type polypyrrole, incluant des macrocycles hetero-bischelatant, depose a la surface d'une electrode de feutre de carbone. Enfin, l'ancrage d'edifices moleculaires complexes termines par une fonction soufree a ete realise sur des surfaces d'or. Les proprietes d'adsorption des thioethers, thiols et disulfures ont ete etudiees et comparees. Les 2-catenates incluant une entite disulfure presentent les caracteristiques les plus satisfaisantes et permettent d'esperer observer des mouvements moleculaires au sein d'une monocouche deposee sur une electrode d'or.

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48

Camallanqui-Alborque, C., G. Quispe, and C. Raymundo-Ibañeez. "Controlled Trim-Blasting Model to Improve Stability and Reduce Vibrations at a Production Gallery of the San Ignacio de Morococha S.A.A. Mining Company." IOP Publishing Ltd, 2019. http://hdl.handle.net/10757/656296.

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This paper presents a blasting method called controlled trim blasting, in which the rock mass of an unstable gallery where high levels of vibration have been detected is analyzed. This methodology comprises a drilling mesh with two-contour gallery assessment, producing its drilling machines and determining the type of explosive used and burden and spacing, which will be detonated after the internal blasting. Further, the internal blasting will possess its drilling machines, burden, spacing, and a second type of explosive. The separation of the gallery into smaller parts will improve the blasting, as verified in the recorded simulation. In addition, the rock-mass stability improves because the explosives used in the perimeter of the gallery are low-power with mild detonation pressure, which does not generate high levels of vibration. This is a practical and efficient method in areas where the rock mass is not good or there is a mixture of rock types.

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49

Lacheretz, Antoine. "L'adhesion bacterienne : application a la prevention de la colibacillose du veau a escherichia coli k99+ et a son controle." Toulouse 3, 1987. http://www.theses.fr/1987TOU30226.

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50

Diodato, Marco. "Fattori di controllo della mobilità e biodisponiblità di elementi potenzialmente tossici (PTE's) nei suoli della Pineta di San Vitale (RA)." Master's thesis, Alma Mater Studiorum - Università di Bologna, 2011. http://amslaurea.unibo.it/1960/.

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