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Establishing a Standardised National Data System for Evaluating Road Maintenance Emissions in SwedenMahmud, Z N M Zarif, Salem, Sajid January 2024 (has links)
A trustworthy and consistent data system is crucial for monitoring and reducing carbon emissions from road maintenance operations. Developing a national data reporting system requires technical support and a systemic plan involving multiple stakeholders to implement the standard. In Sweden, Trafikverket, the Swedish transport agency, recently initiated a project that proposed a solution based on the BEAst standard and outlined the current data collection methods for road maintenance. The BEAst standard is an agreed industry-driven information standard that promotes machine-readable information communication, effectively reduces costs, and increases efficiency by streamlining communication within the industry. This is to address the critical need for a trustworthy data system to monitor and reduce carbon emissions from road maintenance operations. Although the datasystem has high potential to identify the sources of carbon emissions and create mitigation measures by precisely gathering fuel use data throughout operations and maintenance activities. There are many challenges in integrating data from diverse sources into a consistent system revealed several obstacles, including differences in CO2 emissions reported by different systems, human factors affecting data quality,and limited access to cloud services. To address these challenges, this study proposes a new data reporting mechanism which requires a detailed specification of reporting parameters covering content, format, resolution, and reporting frequency using BEAst standards.
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Machine Learning for State Estimation in Fighter Aircraft / Maskininlärning för tillståndsestimering i stridsflygplanBoivie, Axel January 2023 (has links)
This thesis presents an estimator to assist or replace a fighter aircraft’s air datasystem (ADS). The estimator is based on machine learning and LSTM neuralnetworks and uses the statistical correlation between states to estimate the angleof attack, angle of sideslip and Mach number using only the internal sensorsof the aircraft. The model is trained and extensively tested on a fighter jetsimulation model and shows promising results. The methodology and accuracyof the estimator are discussed, together with how a real-world implementationwould work. The estimators presented should act as a proof of concept of thepower of neural networks in state estimation, whilst the report discusses theirstrengths and weaknesses. The estimators can estimate the three targets wellin a vast envelope of altitudes, speeds, winds and manoeuvres. However, thetechnology is quite far from real-world implementation as it lacks transparencybut shows promising potential for future development. / Det här examensarbetet presenterar en estimator för att hjälpa eller ersätta ettstridsflygplans luftdatasystem (ADS). Estimatorn är baserad på maskininlärningoch LSTM neurala nätverk och använder statistisk korrelation mellan tillstånd föratt uppskatta anfallsvinkeln, sidglidningsvinkel och Mach-tal endast med hjälpav flygplanets interna sensorer. Modellen är tränad och utförligt testad på ensimuleringsmodell för stridsflygplan och visar lovande resultat. Estimatornsmetodik och noggrannhet diskuteras, tillsammans med hur en implementeringi verkligheten skulle fungera. De presenterade estimatorerna bör fungera somett “proof of concept” för kraften hos neurala nätverk för tillståndsuppskattning,medan rapporten diskuterar deras styrkor och svagheter. Estimatorerna kanuppskatta de tre tillstånden väl i ett stort spektra av altituder, hastigheter, vindaroch manövrar. Tekniken är dock ganska långt ifrån en verklig implementeringeftersom den saknar transparens, men visar lovande potential för framtidautveckling.
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La circulation de la donnée à caractère personnel relative à la santé : disponibilité de l’information et protection des droits de la personne / Free movement of personal health data : Information availability and rights of data subjectBrasselet, Renato 03 December 2018 (has links)
La e santé, la m-santé et la quantification de soi connectent le corps et bousculent le modèle traditionnel du soin. Ils le font glisser d’une médecine curative et monopolistique à une médecine préventive et adoptant une approche de la santé telle que définie par l’OMS. Par ce truchement, la personne n’est plus simplement placée au centre du dispositif de soin elle en devient l’un des acteurs y compris dans l’intimité de sa vie privée. Par ailleurs, sans cesse à la recherche de la réalisation d’économie mais aussi de qualité, le système de santé, a muté, sous l’effet du déploiement de l’e-santé. Il en résulte qu’il est désormais substantiellement décloisonné et ne peut plus être synthétisé dans la dichotomie classique entre le sanitaire et le médico-social. Le vecteur et la résultante de ce phénomène consiste dans la circulation de l’information de santé. Désormais majoritairement numérisée elle est devenue indispensable au soin ainsi qu’au fonctionnement du système de santé. Le soin est désormais conçu autour de l’échange et du partage catégoriel et inter-catégoriel, voire même homme-machine ou machine-machine et non plus sur une médecine fondée sur le secret. L’Homme devenu homo numericus n’en est pas pour autant dépourvu de tout droits et de toute intimité. Le droit et la techno-droit s’inscrivent dans ce jeu savant dont la moindre réforme inconséquente pourrait en bouleverser l’équilibre précaire / Health, m-health and self quantification connect the body and disrupt the traditional model of care. They are moving it from curative and monopoly medicine to preventive medicine and taking a WHO-defined approach to health. By this means, the person is no longer simply placed at the center of the care device he becomes one of the actors including in the intimacy of his privacy.On the other hand, in search of the realization of economy but also of quality, the health system, has mutated, under the effect of the deployment of e-health. As a result, it is now substantially landscaped and can no longer be synthesized into the classic dichotomy between health and social medicine. The vector and resultant of this phenomenon consists in the circulation of health information. From now on, it has become largely digital and essential for the care and functioning of the healthcare system. The care is now conceived around categorical and inter-categorical exchange and sharing, even man-machine or machine-machine and no longer on a medicine based on secrecy. The Man who has become a homo Numericus is not without all rights and privacy. Law and techno-law are part of this scholarly game, the slightest inconsistent reform of which could upset its precarious balance
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O estudo da acur?cia da resson?ncia magn?tica multiparam?trica no diagn?stico do c?ncer de pr?stataMoraes, M?rcia Cristina Gon?alves de Oliveira 30 August 2017 (has links)
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Previous issue date: 2017-08-30 / Abstract: Today, the incidence of prostate cancer is considered high, however, unlike other malignant tumours, there is an expressive number of cases in which prostate cancer does not progress to clinical disease. The management of patients with prostate cancer should be individually fitted due to the broad behaviour spectrum of this cancer, ranging from low grade tumours with low aggressive biological characteristics to high grade tumours with metastatic capacity. The possibility of predicting the future behavior of the disease allows the selection of the most appropriate conduct for each case. Studies have shown that mpMRI (multiparametric Magnetic Resonance Imaging) has a high negative predictive value for clinically significant prostate cancer, indicating that its application as a screening method and as assessment method of disease progression is promising. To standardize the protocols and reports of prostate mpMRI, the PI-RADS v2 (Prostate Imaging Reporting and Data System version 2) was launched in 2015. Multiparametric Magnetic Resonance Imaging standardized by PI-RADSv2 has been taking a prominent place in the management of prostate cancer, but the specificity and positive predictive value still need to be improved. Purpose: To assess whether the ADC (Apparent diffusion coefficient) value and tumour ADC ratio associated with PI-RADS v2 may increase accuracy in predicting clinically significant prostate cancer. Materials and methods: 91 individuals with suspected prostate cancer were retrospectively studied through mpMRI imaging standardized by PI-RADS v2, obtaining the ADC value from the tumour and the contralateral tissue. The findings were correlated to anatomopathological study (biopsy, prostatectomy or transurethral resection). Results: Accuracy, sensitivity, specificity, positive predictive value and negative predictive value for the consensus between the two reviewers using PI-RADS v2, category 3 associated with categories 4 and 5 for the detection of clinically significant cancer were 70.3%, 97.4%, 50.9%, 58.7% and 96.4% (p <0.001), respectively. The association of the ADC value (<0.795x10-3) to categories 3, 4 and 5 of the PI-RADSv2, in turn, demonstrated accuracy, specificity and positive predictive value of 78.9%, 84.9% and 76.5%; and the association with the tumour ADC ratio (<0.62) presented 77.5%, 86.5% and 77.4% of accuracy, specificity and positive predictive value, respectively. Conclusion: The association of the ADC value and the tumour ADC ratio to the PI-RADS v2 in mpMRI increases the accuracy, specificity and positive predictive value in the detection of aggressive prostate cancer, and may help in the screening of individuals who would undergo invasive procedures and radical therapy, or conservative management, as active surveillance or watchful waiting. / Introdu??o: ? considerada alta a incid?ncia de c?ncer de pr?stata na atualidade, contudo, diferentemente de outras neoplasias, existe um n?mero expressivo de casos em que o c?ncer de pr?stata n?o evolui para a doen?a cl?nica. Por este motivo, o manejo dos pacientes com neoplasia prost?tica deve ser moldado individualmente face ao amplo espectro que varia desde tumores de baixo grau, com caracter?sticas biol?gicas de baixa agressividade, a tumores de alto grau, com capacidade metast?tica. A possibilidade de prever o comportamento futuro da doen?a permite a sele??o da conduta mais adequada para cada caso. Estudos vem comprovando que a Resson?ncia Magn?tica multiparam?trica (RMmp) apresenta um alto valor preditivo negativo para o c?ncer de pr?stata com signific?ncia cl?nica, indicando que sua aplica??o como m?todo de triagem e na avalia??o da progress?o da doen?a ? promissora. Para padronizar os protocolos e os relat?rios da RMmp da pr?stata foi lan?ado em 2015 o PI-RADS v2 (?Prostate Imaging Reporting and Data System? vers?o 2). A RMmp padronizada pelo PI-RADS v2 vem assumindo um lugar de destaque no manejo do c?ncer de pr?stata, contudo, ainda s?o considerados baixos a Especificidade e o Valor Preditivo Positivo. Objetivos: Avaliar se o valor de ADC (?Apparent diffusion coefficient? = Coeficiente de Difus?o Aparente) e a raz?o tumoral do ADC associados ao PI-RADS v2 podem aumentar a acur?cia da RMmp na predi??o do c?ncer de pr?stata com signific?ncia clinica. Materiais e m?todos: Foram estudados retrospectivamente 91 indiv?duos com suspeita de c?ncer de pr?stata, submetidos a RMmp padronizada pelo PI-RADS v2, obtendo-se o ADC quantitativo da les?o e do tecido contralateral. Os achados foram correlacionados ao estudo anatomopatol?gico (bi?psia, prostatectomia ou ressec??o transuretral). Resultados: A acur?cia, sensibilidade, especificidade, valor preditivo positivo e valor preditivo negativo para o consenso entre os dois avaliadores utilizando a RMmp padronizada pelo PI-RADS v2, com a categoria 3 associada as categorias 4 e 5 para a detec??o do c?ncer com signific?ncia cl?nica foram 70,3%; 97,4%; 50,9%; 58,7% e 96,4% (p<0,001), respectivamente. A associa??o do valor do ADC (<0,795x10-3) ?s categorias 3, 4 e 5 do PI-RADS v2, por sua vez, demonstrou acur?cia, especificidade e valor preditivo positivo de 78,9%; 84,9% e 76,5%; e a associa??o com a raz?o tumoral do ADC (< 0,62), apresentou 77,5%; 86,5% e 77,4% de acur?cia, especificidade e valor preditivo positivo, respectivamente. Conclus?o: A associa??o do valor do ADC e da raz?o tumoral do ADC ao PI-RADS v2 na RMmp aumenta a acur?cia, especificidade e valor preditivo positivo na detec??o do c?ncer agressivo da pr?stata, podendo auxiliar na triagem dos indiv?duos e na decis?o entre
a conduta agressiva, com procedimentos invasivos e terapia radical, ou a conduta conservadora, com vigil?ncia ativa ou observa??o.
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Sistema de informação para ajuste dos dados de tensão-deformação nos ensaios de compactação do solo / Information system for data adjustment of strengthdeformation assays of soil compactionLamb, Juliano Rodrigo 13 December 2006 (has links)
Made available in DSpace on 2017-05-12T14:46:58Z (GMT). No. of bitstreams: 1
Juliano Rodrigo Lamb.pdf: 4074636 bytes, checksum: e152dd65f2e1908fcbcc8453bea47e89 (MD5)
Previous issue date: 2006-12-13 / The soil compaction is a harmful phenomenon to the agricultural sector,
intensified with the current model of culture adoption though the use of
machines weighed in the culture systems, where these can exert superior
pressures to the soil load support capacity. With the soil compaction and
compression there is a reduction of the void ratios face to the air and water
expulsion, that composes the system, harming the water absorption and
minerals for the plants roots, as well as increasing the resistance of the ground
to the penetration. By the way, it is formed becomes important the
accomplishment of trials of compression for determination of the compaction
levels, either in field through assays in situ or laboratory trials. The difficulty
presented in trials of this nature, this related with the analysis of the gotten data
and with the determination of the compression curves and stress point. Face
this conjuncture one utilized the systems of information with the development of
application of data base for the adjustment of the data of tension-deformation in
trials in situ and laboratory. The system was developed using the environment
of development Borland© Delphi© with data base Firebird and methodologies
Oriented Objects and to 3Tier. With data proceeding from carried through trials,
the software have demonstrated to efficiency in the reading and filtering of in
situ trials data, security in the storage of all the referring data to the trials, as
well as agility and precision in the determination of the curves of compression of
the ground and in the esteem of the stress point. The results still allow
concluding that, the traffic of machines in the activities in field intensify the
phenomenon of the compaction, and that sinkage plate and oedometer are
important in the accomplishment of trials of soil compression. / A compactação do solo é um fenômeno danoso ao setor agrícola, intensificado
com a adoção do modelo de produção atual que utiliza nos sistemas de cultivo.
máquinas pesadas que podem exercer pressões superiores à capacidade de
suporte do solo. Com a compactação e compressão do solo ocorre uma
redução do índice de vazios, face à expulsão do ar e da água que compõem o
sistema, prejudicando a absorção de água e minerais pelas raízes das plantas
e aumentando a resistência do solo à penetração. Dessa forma, torna-se
importante a realização de ensaios de compressão para determinação dos
índices de compactação, seja em campo por meio de ensaios in situ ou em
ensaios laboratoriais. A dificuldade apresentada em ensaios desta natureza,
está relacionada à análise dos dados obtidos e com a determinação das curvas
de compressão e índice de pré-consolidação. Face a essa conjuntura
procurou-se a utilização de sistemas de informação com o desenvolvimento de
um aplicativo de banco de dados para o ajuste dos dados de
tensão-deformação em ensaios in situ e em laboratório. O sistema foi
desenvolvido usando o ambiente de desenvolvimento Borland© Delphi© com
banco de dados Firebird e metodologias Orientada a Objetos e 3Tier.
Alimentado com dados provenientes de ensaios realizados, o software
demonstrou eficiência na leitura e filtragem dos dados de ensaios in situ,
segurança no armazenamento de todos os dados referentes aos ensaios, bem
como agilidade e precisão na determinação das curvas de compressão do solo
e na estimação do ponto de pré-consolidação. Os resultados ainda permitem
concluir que o tráfego de máquinas, nas atividades em campo, intensifica o
fenômeno da compactação e que o penetrômetro e o oedômetro são
importantes na realização de ensaios de compressão do solo.
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Sistema de informação para ajuste dos dados de tensão-deformação nos ensaios de compactação do solo / Information system for data adjustment of strengthdeformation assays of soil compactionLamb, Juliano Rodrigo 13 December 2006 (has links)
Made available in DSpace on 2017-07-10T19:23:45Z (GMT). No. of bitstreams: 1
Juliano Rodrigo Lamb.pdf: 4074636 bytes, checksum: e152dd65f2e1908fcbcc8453bea47e89 (MD5)
Previous issue date: 2006-12-13 / The soil compaction is a harmful phenomenon to the agricultural sector,
intensified with the current model of culture adoption though the use of
machines weighed in the culture systems, where these can exert superior
pressures to the soil load support capacity. With the soil compaction and
compression there is a reduction of the void ratios face to the air and water
expulsion, that composes the system, harming the water absorption and
minerals for the plants roots, as well as increasing the resistance of the ground
to the penetration. By the way, it is formed becomes important the
accomplishment of trials of compression for determination of the compaction
levels, either in field through assays in situ or laboratory trials. The difficulty
presented in trials of this nature, this related with the analysis of the gotten data
and with the determination of the compression curves and stress point. Face
this conjuncture one utilized the systems of information with the development of
application of data base for the adjustment of the data of tension-deformation in
trials in situ and laboratory. The system was developed using the environment
of development Borland© Delphi© with data base Firebird and methodologies
Oriented Objects and to 3Tier. With data proceeding from carried through trials,
the software have demonstrated to efficiency in the reading and filtering of in
situ trials data, security in the storage of all the referring data to the trials, as
well as agility and precision in the determination of the curves of compression of
the ground and in the esteem of the stress point. The results still allow
concluding that, the traffic of machines in the activities in field intensify the
phenomenon of the compaction, and that sinkage plate and oedometer are
important in the accomplishment of trials of soil compression. / A compactação do solo é um fenômeno danoso ao setor agrícola, intensificado
com a adoção do modelo de produção atual que utiliza nos sistemas de cultivo.
máquinas pesadas que podem exercer pressões superiores à capacidade de
suporte do solo. Com a compactação e compressão do solo ocorre uma
redução do índice de vazios, face à expulsão do ar e da água que compõem o
sistema, prejudicando a absorção de água e minerais pelas raízes das plantas
e aumentando a resistência do solo à penetração. Dessa forma, torna-se
importante a realização de ensaios de compressão para determinação dos
índices de compactação, seja em campo por meio de ensaios in situ ou em
ensaios laboratoriais. A dificuldade apresentada em ensaios desta natureza,
está relacionada à análise dos dados obtidos e com a determinação das curvas
de compressão e índice de pré-consolidação. Face a essa conjuntura
procurou-se a utilização de sistemas de informação com o desenvolvimento de
um aplicativo de banco de dados para o ajuste dos dados de
tensão-deformação em ensaios in situ e em laboratório. O sistema foi
desenvolvido usando o ambiente de desenvolvimento Borland© Delphi© com
banco de dados Firebird e metodologias Orientada a Objetos e 3Tier.
Alimentado com dados provenientes de ensaios realizados, o software
demonstrou eficiência na leitura e filtragem dos dados de ensaios in situ,
segurança no armazenamento de todos os dados referentes aos ensaios, bem
como agilidade e precisão na determinação das curvas de compressão do solo
e na estimação do ponto de pré-consolidação. Os resultados ainda permitem
concluir que o tráfego de máquinas, nas atividades em campo, intensifica o
fenômeno da compactação e que o penetrômetro e o oedômetro são
importantes na realização de ensaios de compressão do solo.
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La diseguaglianza di opportunità in Italia / INEQUALITY OF OPPORTUNITY IN ITALY / Inequality of Opportunity in ItalyPACE, MARIA LUCIA 13 October 2017 (has links)
La diseguaglianza dei redditi è comunemente analizzata e misurata attraverso l’impiego di varie misure quali l’indice di Gini, il coefficiente di variazione, l’indice di Theil, la varianza dei logaritmi ed altri ancora (Sen, 1970). A partire dagli anni ’90 l’applicazione di tecniche di scomposizione relative, ad esempio, all’indice di Theil hanno reso possibile quantificare due diverse componenti della diseguaglianza ovvero la disuguaglianza legata allo sforzo individuale e la disuguaglianza dovuta alle ineguali opportunità. Questa seconda componente dipende esclusivamente da fattori esogeni, non controllabili dall’individuo, e, per questa ragione, è a ragione considerata una diseguaglianza “ingiusta”. Alla componente residua della scomposizione è di solito attribuito, invece, il significato di disuguaglianza nello sforzo, ovvero quanto ciascun individuo si è impegnato per raggiungere un determinato obiettivo di successo economico. L’applicazione di questo approccio alle misure di diseguaglianza ha permesso di studiare quale tipo di disuguaglianza prevalga all’interno di un Paese e, soprattutto, quali siano le circostanze esogene che incrementano la disparità nelle opportunità. Il presente lavoro si muove lungo questa linea di ricerca proponendo un metodo per testare il peso relativo delle due componenti e la loro significativita’. Come misura di diseguaglianza si e’ scelto di considerare il coefficiente di variazione in modo da ricondurre il test ad un problema di Analisi della varianza (ANOVA) a piu’ vie. Il test viene presentato facendo riferimento ai dati dell’ISTAT e dell'indagine Bankitalia sui redditi delle famiglie. Dopo quest'analisi preliminare sulle determinanti della diseguaglianza di opportunità in Italia, si utilizza la scomposizione della diseguaglianza nelle sue due componenti: diseguaglianza di opportunità e diseguaglianza legata all'impegno, per definire univocamente l'effetto della diseguaglianza sulla crescita economica. L'analisi econometria è svolta sui dati dell'indagine sulla ricchezza e sui redditi delle famiglie forniti dalla Banca d'Italia. L'effetto viene stimato utilizzando il modello panel dinamico con il metodo di stima GMM. / While the analysis of inequality has been central to economic studies for cen- turies, in recent years many studies concentrated on the distinction between in- equality of opportunity (IO) and inequality of returns to effort (IE) and attempted empirical estimates of the two components, e.g. in US and in Europe. The decompo- sition of a general inequality index into these two components allows to analyze the prevalence of fair or unfair income inequality within a country. This paper suggests to test the differences between the two sources of inequality in a simple way using the ANOVA framework adapted to decompose the coefficient of variation, to better suit the requirements of an inequality index. The proposed procedure is applied to the Italian Survey on Income and Living Condition (IT-SILC data, wave 2005 and 2011). The analysis of the results help identifying the circumstances that foster the rise of inequality of opportunities in Italy. Our analysis shows in particular, that father education, region of residence and gender result as the most relevant circumstances determining inequality of opportunity. On the other side, the role of mother education starting from a lower level, as an inequality of opportunity factor, is increasing its influence over time. The decomposition of inequality index in two components allows not only to analyze the prevalence of fair or unfair income inequality in a country, but also to find a clearer relation between inequality and growth. In fact, it is still missing an analysis of the relation between inequality of opportunity and economic growth in Italy. This paper aims at filling in that gap, by using Italian data from Bank of Italys Survey on Income and Wealth from 1998 to 2014. We choose the coefficient of variation to measure inequality of opportunity at the regional level and, then, we studied its relation with economic growth using Dynamic Panel Data models estimated through System- GMM. Finally, in order to check if the coefficient of variation could be a measure as good as the Entropy’s index, I will compare the results of the estimated panel models with the two different inequality of opportunity indeces. We evaluate the effect of inequality of opportunity on different length of the economic growth rate, going from a short term (2 years) to a very long term growth rate (10 years). Our results shows that, in Italy, inequality of opportunity is negative in the short period, but it does not have any effect on long run growth.
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Diagnostic Test Accuracy Systematic Reviews: Summarizing the Evidence of Diagnostic Approaches in Cancer-Related ImagingDawit, Haben Tesfu 28 June 2023 (has links)
Systematic reviews on diagnostic test accuracy studies provide an overview of the current literature in a systematic and transparent manner. They are the highest level of evidence in clinical research, therefore they are critical to decision-making in the healthcare setting. Cancer is the primary source of mortality in Canada, however early detection of tumors can improve the survival rates and long-term health outcomes of patients. The primary method of cancer diagnosis is histopathological assessment, however, its use remains controversial. It is an invasive procedure and requires resources and clinical expertise not readily available. Noninvasive clinical imaging has been studied as a clinically desirable method for cancer diagnosis, however its diagnostic accuracy has yet to be established in the medical setting. With the increased role of DTA research in medicine, the current literature needs to be summarized in an effective way to properly educate and influence clinical decision-making. The objective of this thesis is to address the current evidence gaps in DTA research by conducting several systematic reviews to evaluate the accuracy of diagnostic methods in cancer-related imaging. The last chapter of the thesis will provide a critical reflection on the current landscape of DTA studies in cancer-related imaging, based on the findings of the reviews in the thesis.
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Improved Robust Stability Bounds for Sampled Data Systems with Time Delayed Feedback ControlKurudamannil, Jubal J. 15 May 2015 (has links)
No description available.
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Contribution à la commande robuste des systèmes à échantillonnage variable ou contrôlé / Contribution to the control of systems with time-varying and state-dependent samplingFiter, Christophe 25 September 2012 (has links)
Cette thèse est dédiée à l'analyse de stabilité des systèmes à pas d'échantillonnage variable et à la commande dynamique de l'échantillonnage. L'objectif est de concevoir des lois d'échantillonnage permettant de réduire la fréquence d'actualisation de la commande par retour d'état, tout en garantissant la stabilité du système.Tout d'abord, un aperçu des récents défis et axes de recherche sur les systèmes échantillonnés est présenté. Ensuite, une nouvelle approche de contrôle dynamique de l'échantillonnage, "échantillonnage dépendant de l'état", est proposée. Elle permet de concevoir hors-ligne un échantillonnage maximal dépendant de l'état défini sur des régions coniques de l'espace d'état, grâce à des LMIs.Plusieurs types de systèmes sont étudiés. Tout d'abord, le cas de système LTI idéal est considéré. La fonction d'échantillonnage est construite au moyen de polytopes convexes et de conditions de stabilité exponentielle de type Lyapunov-Razumikhin. Ensuite, la robustesse vis-à-vis des perturbations est incluse. Plusieurs applications sont proposées: analyse de stabilité robuste vis-à-vis des variations du pas d'échantillonnage, contrôles event-triggered et self-triggered, et échantillonnage dépendant de l'état. Enfin, le cas de système LTI perturbé à retard est traité. La construction de la fonction d'échantillonnage est basée sur des conditions de stabilité L2 et sur un nouveau type de fonctionnelles de Lyapunov-Krasovskii avec des matrices dépendant de l'état. Pour finir, le problème de stabilisation est traité, avec un nouveau contrôleur dont les gains commutent en fonction de l'état du système. Un co-design contrôleur/fonction d'échantillonnage est alors proposé / This PhD thesis is dedicated to the stability analysis of sampled-data systems with time-varying sampling, and to the dynamic control of the sampling instants. The main objective is to design sampling laws that allow for reducing the sampling frequency of state-feedback control for linear systems while ensuring the system's stability.First, an overview of the recent problems, challenges, and research directions regarding sampled-data systems is presented. Then, a novel dynamic sampling control approach, "state-dependent sampling", is proposed. It allows for designing offline a maximal state-dependent sampling map over conic regions of the state space, thanks to LMIs.Various classes of systems are considered throughout the thesis. First, we consider the case of ideal LTI systems, and propose a sampling map design based on the use of polytopic embeddings and Lyapunov-Razumikhin exponential stability conditions. Then, the robustness with respect to exogenous perturbations is included. Different applications are proposed: robust stability analysis with respect to time-varying sampling, as well as event-triggered, self-triggered, and state-dependent sampling control schemes. Finally, a sampling map design is proposed in the case of perturbed LTI systems with delay in the feedback control loop. It is based on L2-stability conditions and a novel type of Lyapunov-Krasovskii functionals with state-dependent matrices. Here, the stabilization issue is considered, and a new controller with gains that switch according to the system's state is presented. A co-design controller gains/sampling map is then proposed
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