Thèse de 3e cycle : SCIENCES APPLIQUEES : Metz : 1985. / 32 REF.

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Doctor en Ingeniería Eléctrica / Hoy en día, la construcción de maquinaria y plantas industriales exigen soluciones de accionamiento con un diseño flexible y escalable. En sectores industriales como la petroquímica, la minería, la generación de energía, etc., existe una demanda de soluciones con alta eficiencia, seguridad integrada y respaldo de las compañías proveedoras. En este contexto, el Convertidor Multinivel Modular (MMC) ha aparecido como una opción prometedora para accionamientos de media tensión de alta potencia debido a sus características, como modularidad total, flexibilidad de control, niveles de media tensión, calidad de potencia y posible operación sin transformador. Por lo tanto, esta tesis discute la aplicación del MMC para accionamientos de máquinas. El modelado del MMC y sus sistemas de control asociados para esta aplicación son analizados ampliamente en este documento. Específicamente, se ha propuesto un nuevo modelado basado en coordenadas dq y su sistema correspondiente sistema de control para regular el valor instantáneo de las tensiones de los condensadores del MMC. Además, se ha propuesto la integración de los sistemas de control de la máquina y del MMC para mejorar el rendimiento general del sistema. Por ejemplo, se demostró que las corrientes circulantes requeridas durante bajas frecuencias ac se reducen al considerar la interacción de ambos sistemas de control. La efectividad de las estrategias de control propuestas se validó a través de extensos resultados experimentales, que se han publicado en dos artículos (IEEE Transactions on Industrial Electronics) y seis artículos de conferencia (indexados en la base de datos Scopus), así como contribuciones importantes en otros proyectos relacionados con el control de convertidores multinivel modulares. El prototipo utilizado se compone de 18 celdas de potencia. El sistema se controla utilizando un procesador de señales digitales y dos FPGAs. Un segundo MMC con 12 celdas de potencia también se usó para algunas pruebas, conformando una unidad Back-to-Back MMC. Se probó el rendimiento dinámico y en estado estable de las metodologías de control propuestas, considerando el arranque del MMC, cambios escalón tanto en el par y las corrientes de magnetización, rampas de velocidad, pruebas de cruce por velocidad cero, operación de rotor bloqueado, operación con flujo debilitado, diferentes condiciones de carga, manipulación de la tensión dc del MMC, etc. En todos los casos, el rendimiento alcanzado es consistente con los resultados esperados. Nowadays, machinery and plant construction are demanding drive solutions with flexible and scalable design. In industrial sectors such as petrochemical, mining, power generation, etc., there is a demand for solutions with high efficiency, integrated safety and support from the supplier companies. In this context, the Modular Multilevel Converter (MMC) has appeared as a promising option for high-power medium-voltage drives due to their characteristics, such as full modularity, control flexibility, medium-voltage levels, power quality and possible transformer-less operation. Thereby, this thesis discusses the application of the MMC as a machine drive. The modelling and control systems required for this application are extensively analysed and discussed in this document. Specifically, a novel dq-based modelling of the MMC and its associated control system has been proposed to regulate the instantaneous value of the MMC capacitor voltages. Additionally, the integration of the machine and MMC control systems has been proposed to enhance the performance of the overall system. For example, it was demonstrated that the required circulating currents during low-ac frequencies are reduced by considering the interaction of both control systems. The effectiveness of the proposed control strategies is validated through extensive experimental results, which have been published in two journal papers (IEEE Transaction on Industrial Electronics) and six conference papers (indexed in the Scopus database), as well as important contributions in other projects related to the control of modular multilevel converters. The downscaled prototype utilised is composed of 18 power cells. The system is controlled using a Digital Signal Processor and two Field Programmable Gate Arrays (FPGAs). A second MMC with 12 power cells was also used for some tests, conforming a Back-to-Back MMC-based drive. The dynamic and steady-state performance of the proposed control methodologies were tested, considering the MMC starting-up, step changes in both the torque and magnetising currents, speed-ramps, zero-speed crossing test, rotor-locked operation, flux-weakening operation, different loading conditions, manipulation of the input voltage of the MMC, etc. In all cases, the achieved performance is consistent with the expected results.

[ES] Las infusiones exógenas de insulina son vitales para las personas con diabetes tipo 1 para suplir parcialmente la incapacidad del páncreas de secretar insulina. Sin embargo, las terapias intensivas actuales pueden restringir la calidad de vida de los pacientes. Los pacientes con esta enfermedad tienen que tomar decisiones constantemente sobre las dosis de insulina que lleva a la glucosa a niveles seguros. Si no lo consiguen, pueden sufrir las complicaciones crónicas y agudas derivadas de los niveles anormalmente altos o bajos de glucosa. La regulación automática de glucosa con sistemas de páncreas artificial prometía reducir la carga del autocontrol de la enfermedad al mismo tiempo que se mejoraba el tiempo en normoglucemia y se reducía la variabilidad. Sin embargo, estas promesas sólo se han cumplido parcialmente. Aunque esta tecnología mejora el control glucémico que logran las terapias tradicionales, la ingesta de alimentos y la práctica de ejercicio limitan la eficiencia de los sistemas de páncreas artificial durante el día. De hecho, los sistemas comerciales sólo pueden hacerles frente con la ayuda de los pacientes. Para compensar las ingestas, los pacientes deben anunciar el contenido de carbohidratos al sistema. Para el ejercicio, deben anunciar el inicio de la actividad o tomar medidas preventivas como modificar la referencia de glucosa o reducir la basal con mucha antelación. Estas exigencias no sólo no ayudan a reducir la carga del paciente, sino que pueden comprometer la eficiencia del sistema cuando el paciente se equivoca al estimar los carbohidratos, omite el anuncio de la comida o no puede planificar el ejercicio. Así pues, esta tesis propone nuevos métodos para eliminar el anuncio de ingestas y ejercicio lo que ayudaría a reducir la intervención del paciente en los sistemas de páncreas artificial, y, en consecuencia, mejorar la calidad de vida. Desde un punto de vista de control, las ingestas y el ejercicio pueden considerarse perturbaciones. Esta tesis explota métodos de la literatura de rechazo de perturbaciones y acomodación de fallos para lograr el objetivo de la tesis. En concreto, hay que destacar tres aplicaciones: 1) se ha desarrollado un observador super-twisting para detectar comidas no anunciadas como primer paso para su compensación; 2) se ha diseñado un observador de modos deslizantes de primer orden para la estimación de la ratio de aparición de glucosa, la cual ha sido integrada en un generador de bolos para compensar las comidas; 3) se ha empleado el principio de diseño por modelo interno para mitigar el efecto de las ingestas de alimentos y ejercicio, añadiendo sugerencias de carbohidratos de rescate a la insulina. Como resultado, las contribuciones de esta tesis allanan el camino para el desarrollo de sistemas de páncreas artificial sin anuncios, que liberen al paciente de la carga de la gestión de la diabetes. / [CA] Les infusions exògenes d'insulina són vitals per a les persones amb diabetis tipus 1 per a suplir parcialment l'incapacitat del pàncrees de secretar insulina. No obstant, les teràpies intensives actuals poden restringir la qualitat de vida dels pacients. Les persones amb aquesta malaltia han de prendre decisions contínuament sobre la dosi d'insulina que fa que la glucosa estiga en valors segurs. Si no ho aconsegueixen, poden sofrir les complicacions cròniques i agudes derivades dels nivells anormalment alts o baixos de glucosa. La regulació automàtica de glucosa amb sistemes de pàncrees artificials prometia reduir la càrrega d'autocontrol de la malaltia al mateix temps que es millorava el temps en normoglucèmia i es reduïa la variabilitat. No obstant, aquestes promeses s'han complit només parcialment. Encara que aquesta tecnologia millora el control de la glucosa, la ingesta d'aliments i la pràctica d'exercici limiten l'eficiència dels sistemes de pàncrees artificials durant el dia. De fet, els sistemes comercials només poden fer-les front amb la ajuda dels pacients. Per a compensar les ingestes, el pacients han d'anunciar al sistema la quantitat de carbohidrats. Per al exercici, han d'anunciar l'inici de l'activitat o prendre mesures preventives com modificar la referència de glucosa o reduir la infusió basal d'insulina. Aquestes exigències no només no ajuden a reduir la càrrega al pacient, sinó que poden comprometre l'eficiència del sistema quan el pacient confon la estimació dels carbohidrats, omet l'anunciament de la ingesta o no pot planificar l'exercici. Així doncs, aquesta tesi proposa nous mètodes per a eliminar l'anunciament d'ingestes i exercici permetent reduir així la intervenció del pacient, i, en conseqüència, millorar la qualitat de vida. Des del punt de vista de control, les ingestes i el exercici poden considerar-se pertorbacions. Aquesta tesi explota mètodes de la literatura de rebuig de pertorbacions i acomodament de fallades. En particular, es destaquen tres aplicacions: 1) s'ha desenvolupat un observador super-twisting per a detectar ingestes no anunciades com a primer pas per a la seua compensació; 2) se ha dissenyat un observador de modes lliscants per a estimar el rati d'aparició de glucosa de la ingesta, el qual s'ha integrat en un generador de bols d'insulina per compensar les ingestes; 3) se ha empleat el principi de disseny per model intern per a mitigar l'efecte de les ingestes i exercici, incorporant recomanacions de carbohidrats a la insulina. Com a resultat, les contribucions d'aquesta tesi obren el camí per a desenvolupar sistemes de pàncrees artificial sense anunciaments, que alliberen al pacient de la càrrega de la gestió de la diabetis. / [EN] Exogenous insulin infusions are vital for people with type 1 diabetes to partially make up for the inability of the pancreas to secrete insulin. However, current intensive therapies may restrict patients' quality of life. People with this disease have to constantly make decisions about insulin doses to bring glucose levels to a safe range. If unsuccessful, they may suffer from chronic and acute complications related to abnormally high and low glucose values. The automatic regulation of glucose with artificial pancreas systems promised to reduce patients' self-control burdens while improving time in normoglycemia and decreasing variability. However, these promises are fulfilled only partially. Although this technology outperforms the glycemic outcomes achieved by conventional therapies, meal intake and physical activity limit its daytime performance. Indeed, commercially available systems only can handle them with the support of the patients. For meals, patients must announce the carbohydrate content to the system. For exercise, they must notify the activity or take preventive actions like changing glucose setpoint or decreasing basal well ahead before exercise. These demands do not help reduce the patient's burden. They even can compromise the system performance when the patient misestimates the carbohydrate content, omits the meal announcement, or cannot plan the exercise event. Hence, this thesis proposes new methods to eliminate the need for meal and exercise announcements, thus reducing patient intervention in artificial pancreas systems for a better quality of life. From a control perspective, meals and exercise can be regarded as disturbances; therefore, this thesis exploits methods from the disturbance rejection and fault accommodation literature to achieve the thesis goal. Specifically, the following three applications must be highlighted: 1) a super-twisting-based residual generator has been developed to detect unannounced meals as the first step to their compensations; 2) a sliding-mode disturbance observer has been designed to estimate the glucose meal appearance, which is fed into a bolusing algorithm to compensate the meals; 3) the internal model principle is employed to mitigate the effects of meal intakes and exercise, supplementing insulin infusions with carbohydrate recommendations. As a result, the contributions of this thesis pave the way for the development of announcement-free artificial pancreas systems, releasing patients from the burden of diabetes management. / This work was partially supported by: grant DPI2016-78831-C2-1-R funded by MCIN/AEI/10.13039/501100011033 and by “ERDF A way of making Europe”; grant PID2019-107722RB-C21 funded by MCIN/AEI/10.13039/501100011033; and grant ACIF/2017/021 funded by the Generalitat Valenciana through European Social Funds (FSE). Also, the grant BEFPI/2019/077, funded by the Generalitat Valenciana through FSE funds, supported a 7-month research stay at Physiological da University (Óbudai Egyetem, Óbuda, Budapest, Hungary) / Sala Mira, I. (2023). New Contributions Towards Meal and Exercise Announcement-Free Artificial Pancreas Systems [Tesis doctoral]. Universitat Politècnica de València. https://doi.org/10.4995/Thesis/10251/192684

by Elizabeth R. Ducot. / "August 1982." / Bibliography: p. 61-62. / Air Force Office of Scientific Research contract AFOSR-80-0229

Gemeinsamer Workshop von Universitaetsrechenzentrum und Professur "Rechnernetze und verteilte Systeme" der Fakultaet fuer Informatik der TU Chemnitz. Workshop-Thema: Mobilitaet

Gemeinsamer Workshop von Universitaetsrechenzentrum und Professur "Rechnernetze und verteilte Systeme" der Fakultaet fuer Informatik der TU Chemnitz. Workshop-Thema: Mobilitaet

Entanglement is a fundamental property of quantum systems and its characterization is a central problem for physics. Moreover, there is an increasing demand for scalable protocols that can certify the presence of entanglement. This is primarily due to the role of entanglement as a crucial resource for quantum technologies. However, systematic entanglement certification is highly challenging, and this is particularly the case for quantum many-body systems. In this dissertation, we tackle this challenge and introduce some techniques that allow the certification of multipartite entanglement in many-body systems. This is demonstrated with an application to a model of interacting fermions that shows the presence of resilient multipartite entanglement at finite temperatures. Moreover, we also discuss some subtleties concerning the definition entanglement in systems of indistinguishable particles and provide a formal characterization of multipartite mode entanglement. This requires us to work with an abstract formalism that can be used to define entanglement in quantum many-body systems without reference to a specific structure of the states. To further showcase this technique, and also motivated by current quantum simulation efforts, we use it to extend the framework of entanglement witnesses to lattice gauge theories. / L'entanglement è una proprietà fondamentale dei sistemi quantistici e la sua caratterizzazione è un problema centrale per la fisica. Inoltre, vi è una crescente richiesta di protocolli scalabili in grado di certificare la presenza di entanglement. Ciò è dovuto principalmente al ruolo dell'entanglement come risorsa cruciale per le tecnologie quantistiche. Tuttavia, la certificazione sistematica dell'entanglement è molto impegnativa, e questo è particolarmente vero per i sistemi quantistici a molti corpi. In questa dissertazione, affrontiamo questa sfida e introduciamo alcune tecniche che consentono la certificazione dell'entanglement multipartito in sistemi a molti corpi. Ciò è dimostrato con un'applicazione a un modello di fermioni interagenti che mostra la presenza di entanglement multipartito resiliente a temperature finite. Inoltre, discutiamo anche alcune sottigliezze riguardanti la definizione di entanglement in sistemi di particelle indistinguibili e forniamo una caratterizzazione formale dell'entanglement multipartito. Ciò ci richiede di lavorare con un formalismo astratto che può essere utilizzato per definire l'entanglement nei sistemi quantistici a molti corpi senza fare riferimento a una struttura specifica degli stati. Per mostrare ulteriormente questa tecnica, e anche motivata dagli attuali sforzi di simulazione quantistica, la usiamo per estendere la struttura dei testimoni di entanglement alle teorie di gauge del reticolo.

Detta Examensarbete utfördes som en fallstudie Saab Combat Systems, som är och undersöker utmaningar i form av beroenden och osäkerheter som uppstår i Multiprojekt-Organisationer. Dessa utmaningar verkar orsaka konflikter och tvetydigheter i Multiprojekt-Organisationer gällande exempelvis, kommunikation, resursallokering, produktutveckling samt maktstrukturer mellan olika roller (Engwall & Jerbant, 2003; Dahlgren & Söderlund, 2010). Detta Examensarbete behandlar dessa utmaningar genom att undersöka och besvara följande forskningsfrågor: Vilka utmaningar i form av beroenden och osäkerheter existerar på Saab Combat Systems? Hur kan dessa utmaningar hanteras? Våra resultat visar att tre olika typer av beroenden uppstår i Multiprojekt-Organisationer som utvecklar komplexa produkter och system; organisatoriska beroenden, tekniska beroenden och resursberoenden. Dessa tre beroenden verkar påverka varandra och resultera i osäkerheter när flera projekt hanteras samtidigt. Dessutom ökar nivån av osäkerhet i projekt på grund av osäkerheter i relation till maktstrukturer samt utveckling av komplexa produkter och system. De tre identifierade beroende inkluderar projektosäkerheter samt projektberoenden. Vi har valt ut tre stycken olika typer av Management Control Systems; Projektkontor, Projektportföljhantering samt Programhantering och drar slutsatsen att de kan användas för att hantera de tre identifierade beroendena Multiprojekt-Organisationer. Vi har dock upptäckt att dessa Management Control Systems har både fördelar och nackdelar gällande hantering av de tre olika typer av beroenden. Alla identifierade beroenden och osäkerheter kan följaktligen hanteras genom att kombinera olika Management Control Systems. Dessutom har vi kompletterat en redan utvecklad modell av Dahlgren & Söderlund (2010) genom att kartlägga de tre beroendena, som tar hänsyn till projektosäkerheter och projektberoenden, samt vilken typ av Management Control Systems som är mest lämplig för att hantera dessa beroenden. / This Master Thesis was conducted as a case study at Saab Combat Systems investigating challenges in form of dependencies and uncertainties that emerge in Multi-Project Organizations. These challenges seem to cause conflicts and ambiguity in Multi-Project Organizations regarding for instance; communication, human resources allocation, product development and power structures between different roles (Engwall & Jerbant, 2003; Dahlgren & Söderlund, 2010). Thereby, this Master Thesis addresses these challenges by investigating and answering the following research questions: What challenges in form of dependencies and uncertainties exist at Saab Combat Systems? How can these challenges be addressed? Our Results display that three different types of dependencies exists in Multi-Project Organizations developing Complex Products and Systems; organizational dependencies, technical dependencies and resources dependencies. These three dependencies seem to be connected, and therefore result in uncertainties when managing multiple projects. Additionally, uncertainties in relation to the power structure as well as development of Complex Products and Systems tend to increase the level of project uncertainty. The three identified dependencies include both project uncertainties and project dependencies. We have chosen three different Management Control Systems; Project Management Office, Project Portfolio Management and Programme Management and conclude that they can be utilized in order to address the three identified dependencies in Multi-Project Organizations. However, we have found that these Management Control Systems have benefits as well as shortcomings when addressing different types of dependencies. Consequently, by combining them, all of the identified dependencies and uncertainties can be addressed. Furthermore, we have complemented an already developed model by Dahlgren & Söderlund (2010) by mapping the three identified dependencies, which consider project uncertainties and project dependencies, as well as which Management Control System is most appropriate when addressing these three dependencies.

Negli ultimi anni, parallelamente all’espansione del settore biologico, si è assistito a un crescente interesse per i modelli alternativi di garanzia dell’integrità e della genuinità dei prodotti biologici. Gruppi di piccoli agricoltori di tutto il mondo hanno iniziato a sviluppare approcci alternativi per affrontare i problemi connessi alla certificazione di terza parte. Queste pratiche sono note come Sistemi di Garanzia Partecipativa (PGS). Tali modelli: (i) si basano sugli standard di certificazione biologica dell’IFOAM, (ii) riguardano il complesso dei produttori di una comunità rurale, (iii) comportano l’inclusione di una grande varietà di attori e (iv) hanno lo scopo di ridurre al minimo burocrazia e costi semplificando le procedure di verifica e incorporando un elemento di educazione ambientale e sociale sia per i produttori sia per i consumatori. Gli obiettivi di questo lavoro di ricerca: • descrivere il funzionamento dei sistemi di garanzia partecipativa; • indicare i vantaggi della loro adozione nei Paesi in via di sviluppo e non; • illustrare il caso della Rede Ecovida de Agroecologia (Brasile); • offrire uno spunto di riflessione che riguarda il consumatore e la relativa fiducia nel modello PGS. L’impianto teorico fa riferimento alla Teoria delle Convenzioni. Sulla base del quadro teorico è stato costruito un questionario per i consumatori con lo scopo di testare l’appropriatezza delle ipotesi teoriche. I risultati finali riguardano la stima del livello di conoscenza attuale, la fiducia e la volontà d’acquisto dei prodotti PGS da parte dei consumatori nelle aree considerate. Sulla base di questa ricerca sarà possibile adattare ed esportare il modello empirico in altri paesi che presentano economie diverse per cercare di comprendere il potenziale campo di applicazione dei sistemi di garanzia partecipativa. / In recent years, parallel to the growth of the organic sector, we witnessed an increasing interest in alternative ways to guarantee the integrity and authenticity of organic food. Groups of smallholders worldwide started implementing alternative approaches to cope with problems associated with third-party certification. These practices are known as Participatory Guarantee Systems (PGS). The Participatory Guarantee (i) is based on International Organic Standards issued by IFOAM; (ii) it takes place at the community level; (iii) it involves a wide variety of stakeholders along the supply chain; (iv) it aims to minimize bureaucracy and costs by employing simple verification procedures and incorporating elements of environmental and social education, it improves quality for both producers and consumers. PGS proposal aims to help organic smallholders production and to promote a local food system respecting organic models, biodiversity and a widespread access to organic products. PGS adoption makes organic food affordable even to the poorest consumers mainly through relying upon direct selling and direct trust formation mechanisms. These reduce transaction costs and grant a higher share of added value to farmers. In the thesis is addressed the investigation of PGS through consumers’ behaviour. Its knowledge, indeed, is important in understanding the success and significance of PGS projects. Consumers’ choice has a key role in the comprehension of those factors influencing the success and extent of alternative organic production certification not only in the poorest countries but also in those areas in which third party certification is not affordable to producers. The overall objective concerns the investigation of consumers’ attitude focusing on the level of trust related to non-third party certified products. Afterwards it is analyzed how different levels of consumers’ awareness (participant stakeholder or not) in different areas affects the spending on organic products guaranteed by participatory methods.