WorldCat Identities

École doctorale Mathématiques et sciences et technologies de l'information et de la communication (Rennes)

Works: 378 works in 392 publications in 2 languages and 449 library holdings
Roles: Other
Publication Timeline
Most widely held works by École doctorale Mathématiques et sciences et technologies de l'information et de la communication (Rennes)
Estimation de la pression artérielle par analyse de l'onde de pouls enregistré par un capteur photopléthysmographique by Franck Mouney( )

1 edition published in 2021 in French and held by 2 WorldCat member libraries worldwide

The European Society of Cardiology has highlighted the interest of observing the chronic activity of heart rate, arterial stiffness and blood pressure in order to diagnose as early as possible the cardiovascular diseases which represent a major cause of death in the world. In this context, the work presented in this paper proposes to provide answers on the possibility of blood pressure estimation from the pulse wave signal delivered by a photoplethysmographic sensor (PPG) present on a connected bracelet or watch. Four original contributions of this research work deserve to be briefly mentioned below : the first one concerns an objective comparative study of the temporal characteristics of the PPG signal identified in the scientific literature for the estimation of blood pressure but also new characteristics that we proposed in this thesis from different considerations ; the second contribution concerns the use of a linear prediction algorithm exploiting the PLS model (Projection in Latent Structures) which allowed to have a more detailed view of the contribution of the different temporal characteristics of the PPG signal to the blood pressure estimation in an experimental context (invasive blood pressure measurements) or in an applicative context (non-invasive blood pressure measurements) ; the third contribution is represented by a database that has been created specifically to have significant variations of blood pressure and that could become, we hope, a benchmark database in order to evaluate the capacity of the estimation system to capture these fluctuations ; the fourth contribution concerns the development of a new experimental protocol allowing to induce a rather strong blood pressure variation over a relatively short period of time in order to highlight the essential dynamics of the hemodynamic characteristics specific to the subject considered and thus to better calibrate the blood pressure estimation models
Contribution à l'étude des capacités motrices et cognitives des personnes âgées par traitement de données multivariées by Antoine Jamin( )

1 edition published in 2020 in French and held by 2 WorldCat member libraries worldwide

Le vieillissement est un phénomène complexe ; 30% de la population française en 2020 est considérée comme âgée. Le diagnostic en gériatrie devient donc un enjeu majeur pour notre société pour prévenir et guérir les pathologies liées à l'âge. L'évolution des technologies, avec notamment la réalité virtuelle, permet de développer de nouvelles méthodes de diagnostic plus ludiques. Cycléo est un simulateur de vélo, adapté aux personnes âgées, utilisé actuellement de manière récréative dans des établissements pour seniors. Au cours de son utilisation, le vélo enregistre différentes données comportementales. Dans cette thèse, nous souhaitons répondre à la question suivante : est-il possible de transformer cet appareil de loisir en un outil d'aide au diagnostic gériatrique? Pour ce faire, nous avons utilisé différentes méthodes de traitement du signal (entropie, corrélation croisée, entropie croisée, décomposition modale empirique, diagramme de Bland-Altman, ...) sur les données enregistrées par le vélo. Ce travail préliminaire se structure en deux parties. Dans un premier temps, nous avons considéré les données de Cycléo lors d'un usage récréatif afin d'étudier le rôle de différentes conditions d'utilisation et l'influence de l'âge sur nos résultats. Dans un second temps, nous avons intégré Cycléo dans un protocole d'essai clinique. Notre objectif était d'étudier les éventuelles correspondances entre nos résultats et ceux obtenus grâce à l'utilisation du tapis de marche couramment employé dans les diagnostics gériatriques
Identification automatique des vulnérabilités de sécurité dans les systèmes logiciels by Raounak Benabidallah( )

1 edition published in 2020 in French and held by 2 WorldCat member libraries worldwide

The threat caused by software vulnerabilities is growing exponentially. This phenomenon is due, on the one hand, to the omnipresence of software, and on the other hand, to the large number of existing vulnerabilities. To deal with this problem, several strategies have been developed over time. Some aim to establish good development practices and integrate them right from the design phase, while others consist of carrying out security inspections by identifying vulnerable areas. This thesis is related to the second category of work and focuses on the construction of vulnerability prediction models. The creation of the latter raises various problems. The most important one is the lack of data on software vulnerabilities. For this purpose, we are setting up a complete processing chain from the creation and annotation of a security corpus to the construction and evaluation of vulnerability prediction models. The first contribution of this thesis focuses more on the corpus construction approach than on the corpus itself. The approach is based on the design of vulnerability meta-scanners allowing to identify code vulnerabilities efficiently. This consists in combining several static analysis tools based on their individual performance for each category of vulnerabilities. Our second contribution corresponds to the SecureQualitas corpus which consists of a corpus of Java applications annotated with the vulnerabilities they contain. We build this corpus using a meta- scanner built with three vulnerability analysis tools. Finally, our third contribution is to build a prediction model of vulnerable code. We opted and studied the use of quality metrics to characterize code and we have studied the performance of the models both on categories of vulnerabilities learned by the models and on categories not yet known by the model. The results of our experiments showed the efficiency of the models on both populations of vulnerabilities: known and unknown
Capture, annotation and synthesis of motions for the data-driven animation of sign language avatars by Lucie Naert( )

1 edition published in 2020 in English and held by 2 WorldCat member libraries worldwide

This thesis deals with the capture, annotation, synthesis and evaluation of arm and hand motions for the animation of avatars communicating in Sign Languages (SL). Currently, the production and dissemination of SL messages often depend on video recordings which lack depth information and for which editing and analysis are complex issues. Signing avatars constitute a powerful alternative to video. They are generally animated using either procedural or data-driven techniques. Procedural animation often results in robotic and unrealistic motions, but any sign can be precisely produced. With data-driven animation, the avatar's motions are realistic but the variety of the signs that can be synthesized is limited and/or biased by the initial database. As we considered the acceptance of the avatar to be a prime issue, we selected the data-driven approach but, to address its main limitation, we propose to use annotated motions present in an SL Motion Capture database to synthesize novel SL signs and utterances absent from this initial database. To achieve this goal, our first contribution is the design, recording and perceptual evaluation of a French Sign Language (LSF) Motion Capture database composed of signs and utterances performed by deaf LSF teachers. Our second contribution is the development of automatic annotation techniques for different tracks based on the analysis of the kinematic properties of specific joints and existing machine learning algorithms. Our last contribution is the implementation of different motion synthesis techniques based on motion retrieval per phonological component and on the modular reconstruction of new SL content with the additional use of motion generation techniques such as inverse kinematics, parameterized to comply to the properties of real motions
Unicité et stabilité pour le problème inverse de Steklov by Germain Gendron( Book )

2 editions published in 2020 in French and held by 2 WorldCat member libraries worldwide

We aim at studying an inverse Steklov problem for a particular class of n-dimensional manifolds having the topology of a hollow sphere and equipped with a warped product metric. We prove that the knowledge of the Steklov spectrum determines uniquely the associated warping function up to a natural invariance. Then, we study the continuous dependence of the warping function defining the warped product with respect to the Steklov spectrum
Optimization approaches for minimum conductance graph partitioning by Zhi Lu( )

1 edition published in 2020 in English and held by 2 WorldCat member libraries worldwide

The minimum conductance graph partitioning problem (MC-GPP) is an important NP-hard combinatorial optimization problem with numerous practical applications in various areas such as community detection, bioinformatics, and computer vision. Due to its high computational complexity, heuristic and metaheuristic approaches constitute a highly useful tool for approximating this challenging problem. This thesis is devoted to developing effective metaheuristic algorithms for the MC-GPP. Specifically, we propose a stagnation-aware breakout tabu search algorithm (SaBTS), a hybrid evolutionary algorithm (MAMC), and an iterated multilevel simulated annealing algorithm (IMSA). Extensive computational experiments and comparisons on large and massive benchmark instances (with more than 23 million vertices) demonstrate that the proposed algorithms compete very favorably with stateof- the-art algorithms in the literature. Furthermore, the key issues of these algorithms are analyzed to shed light on their influences over the performance of the proposed algorithms
Étude et développement de solutions de relocalisation d'objets sous-marins par des véhicules sous-marins hétérogènes by Thibaut Nico( Book )

2 editions published in 2019 in English and held by 2 WorldCat member libraries worldwide

In the Mine Counter Measure (MCM) context in the underwater environment, it is vital to revisit some potentially dangerous objects to identify and neutralize them if they are actually mines. This dangerous task was usually performed by humandivers but more and more it is conducted by unmanned underwater robots. Due to the low cost design of the revisit/mine-killer robot, going straightforward to the geolocalized suspicious object does not guarantee that the robot will redetect it.Moreover the robot may dive at a far position from the target and the lack of absolute positioning system in underwater environment demands a strategy to follow to guarantee the revisit of this target. Based on a priori information in the working area and especially the presence of geolocalized landmarks, the problem is solved as a motion planning problem considering uncertainties due to the increasing error when navigating underwater. In the context of bounded errors, the problem is solved in a set-membership manner. Firstly, based on the location and the shape of the landmarks, and on the visibility area of the sensor embedded, the registration maps are computed indicating the sets of robot poses to detect the different landmarks considered in order to reduce the uncertainty on the robot position. Secondly, based on a parametric motion model with uncertain parameters, an high level strategy is provided through a raph optimization. The strategy consists in navigating between the registration maps toreduce each times the uncertainty in position of therobot and finally to guarantee the reachability of agoal area corresponding to the redetection of the target
Accélérateurs matériels sécurisés pour la cryptographie post-quantique by Timo Zijlstra( )

1 edition published in 2020 in English and held by 2 WorldCat member libraries worldwide

Shor's quantum algorithm can be used to efficiently solve the integer factorisation problem and the discrete logarithm in certain groups. The security of the most commonly used public key cryptographic protocols relies on the conjectured hardness of exactly these mathematical problems. A sufficiently large quantum computer could therefore pose a threat to the confidentiality and authenticity of secure digital communication. Post quantum cryptography relies on mathematical problems that are computationally hard for quantum computers, such as Learning with Errors (LWE) and its variants RLWE and MLWE. In this thesis, we present and compare FPGA implementations of LWE, RLWE and MLWE based public key encryption algorithms. We discuss various trade-offs between security, computation time and hardware cost. The implementations are parallelized in order to obtain maximal speed-up. We show that MLWE has the best performance in terms of computation time and area utilization, and can be parallelized more efficiently than RLWE. We also discuss hardware security and propose countermeasures against side channel attacks for RLWE. We consider countermeasures from the state of the art, such as masking and blinding, and propose improvements to these algorithms. Moreover, we propose new countermeasures based on redundant number representation and the random shuffling of operations. All countermeasures are implemented on FPGA to compare their cost and computation time overhead. Our proposed protection based on redundant number representation is particularly flexible, in the sens that it can be implemented for various degrees of protection at various costs
Combinatoire des singularités de certaines courbes et hypersurfaces by Ali Abbas( )

1 edition published in 2017 in English and held by 2 WorldCat member libraries worldwide

The thesis is made up of two parts. In the first part we generalize the Abhyankar-Moh theory to a special kind of polynomials, called free polynomials. We take a polynomial f in K[[x1, ..., xe]][y] and by a preliminary change of variables we may assume that the leading term of the discriminant of f contains a power of x1.After a monomial transformation we get a quasi-ordinary polynomial with a root in K[[x1n1 , ..., x1ne ]] for some n ∈ N. By taking the preimage of f we get asolution y ∈ KC[[x1n1 , ..., x1ne ]] of f(x1, ..., xe, y) = 0,where KC[[x1n1 , ..., x1ne ]] is the ring of formal fractional power series with support in a specific line free cone C. Then we construct the set of characteristic exponents of y, and we generalize some of the results concerning quasi-ordinary polynomials to f. In the second part, we give a procedure to calculate the monoid of degrees of the module M = F1A + . . . + FrA where A = K[f1, ..., fs] andF1, . . . , Fr ∈ K[t]. Then we give some applications to the problem of the classification of plane polynomial curves (that is, plane algebraic curves parametrized by polynomials) with respect to some of the irinvariants, using the module of Kähler differentials
Conception et évaluation d'environnements virtuels pédagogiques : application à la formation professionnelle by Pierre Gac( )

1 edition published in 2020 in French and held by 2 WorldCat member libraries worldwide

The French educational system claims a digital transition. Using digital means is a good way for vocational training professionals to promote new pedagogical approaches. Vocational training suffers from a lack of means to offer new training situations. Thanks to technological improvements, Virtual Reality (VR) is now open to the public. It allows multiple relevant pedagogical simulations that are tailored to the professional world. This thesis is about designing and evaluating virtual environments (VE) in a vocational training context. The design of a training environment implies a high skill diversity for the designer to be usable in real conditions in schools. Like pedagogy for the targeted job or knowledge about students or teachers' profiles. We expand in this manuscript several approaches that allow transcribing a real pedagogical situation into a relevant virtual scenario. For the developer, the complexity of the digitalization process relies on the need for the virtual situation to be suitable for both students and teachers. We propose a generic programming approach, allowing to quickly adapt the design process of a new virtual training scenario. For instance, we propose multi-support generic interactions or a virtual assistant to ease virtual interactions for the trainee. Additionally, students' profiles need to be considered while designing the VR, especially regarding the choices of interactions by simplifying steps. Allowing the designer to remove didactic irrelevant parts for the benefit of more enlightening pedagogical actions. We expand in this thesis some exploitation approaches of VR in a real training context as well as evaluation techniques to assess students. Those discussions are supported by experimental results conducted in high schools to validate our technical and pedagogical approaches detailed in this manuscript
Techniques robustes pour le contrôle automatique des systèmes robotiques by Juan luis Rosendo( Book )

2 editions published in 2019 in English and held by 2 WorldCat member libraries worldwide

This work seeks to mitigate the effects of constraints on mobile robotic systems. To this end, auxiliary control loops and robust tuning techniques are proposed. The former are proposed to mitigate the effects of constraints on the input and output of the systems through the modification of the motion parameter in path following applications.Then, PID controllers are considered as a structural constraint, given its wide use in robotics particularly at low control level. A robust tuning methodology considering this constraint is proposed which achieves good performancelevels even when facing disturbances. Finally, to deal with robustness in presence of robots nonlinearity constraints, an analysis and tuning tool for sliding mode controllers is proposed. The particularity of this tuning method, based on global optimization and interval techniques,is that it allows generating tuning maps of the parameter regions where the desired performance criterion is fulfilled. All the proposed strategies are put into practice, through real experimentation or invalidated simulators, over the AUV Ciscrea available at ENSTA Bretagne
Analyse et modélisation statistique de données de consommation électrique by Kévin Jaunâtre( )

1 edition published in 2019 in French and held by 2 WorldCat member libraries worldwide

In October 2014, the French Environment & Energy Management Agency with the ENEDIS company started a research project named SOLENN ("SOLidarité ENergie iNovation") with multiple objectives such as the study of the control of the electric consumption by following the households and to secure the electric supply. The SOLENN project was lead by the ADEME and took place in Lorient, France. The main goal of this project is to improve the knowledge of the households concerning the saving of electric energy. In this context, we describe a method to estimate extreme quantiles and probabilites of rare events which is implemented in a R package. Then, we propose an extension of the famous Cox's proportional hazards model which allows the etimation of the probabilites of rare events. Finally, we give an application of some statistics models developped in this document on electric consumption data sets which were useful for the SOLENN project. A first application is linked to the electric constraint program directed by ENEDIS in order to secure the electric network. The houses are under a reduction of their maximal power for a short period of time. The goal is to study how the household behaves during this period of time. A second application concern the utilisation of the multiple regression model to study the effect of individuals visits on the electric consumption. The goal is to study the impact on the electric consumption for the week or the month following a visit
Contributions to Hypernym Patterns Representation and Learning based on Dependency Parsing and Sequential Pattern Mining by Ahmad Issa Alaa Aldine( )

1 edition published in 2020 in English and held by 2 WorldCat member libraries worldwide

L'hyperonymie est une relation sémantique entre un terme général et un terme spécifique. Les approches pour extraire de telles relations à partir des textes ont connu un regain d'intérêt en raison de la disponibilité d'une gamme de ressources textuelles ainsi que de leur rôle clé dans la construction de l'ontologie. Généralement, il existe deux types de ces approches : celles basées sur des patrons et celles distributionnelles. L'approche basée sur des patrons s'avère être plus intéressante que l'approche distributionnelle pour la construction de l'ontologie, ce qui est dû au fait que la première permet d'extraire de relations explicites à partir des textes avec une grande précision. Dans cette thèse, nous nous intéressons sur les patrons et nous introduisons une approche pour améliorer systématiquement les performances des patrons. Notre approche est basée sur le couplage d'une fouille des patrons séquentiels avec une représentation de patrons spécifique en utilisant les dépendances grammaticales pour l'apprentissage des patrons d'hyperonymie et d'anti-hyperonymie. Les résultats confirment que notre approche peut apprendre les patrons qui surpassent les approches non supervisées et une approche supervisée basée sur des patrons. Cependant, bien que les meilleures performances soient obtenues par certaines approches distributionnelles supervisées utilisant l'incorporation de mots, les patrons peuvent extraire de relations d'hyperonymie distinctes. Cela confirme que les deux types d'approches sont complémentaires. De plus, d'autres expériences confirment également que l'approche proposée tend à apprendre des patrons génériquement valides à travers divers corpora
Elaboration of personalized projects for users in social and medico-social sector : automatic planning and data objectification by Yinuo Li( )

1 edition published in 2021 in English and held by 2 WorldCat member libraries worldwide

Social and medico-social sector in France assembles all structures where different categories of vulnerable populations arehosted. In addition to the daily care, these centers have to ensure the implementation of the personalized project for each resident in response to his/her needs in comply with national legal provisions. A personalized project is composed of a set of activities chosen among available activities proposed by a center. This thesis deals with the main issue of elaborating feasible and thoughtful personalized projects, which aims to improve the whole efficiency of project implementation in socialand medico-social structures. Specifically, we provide a formal modeling for the user project planning problem and several solution methods including two mathematical programming models, a constructive greedy heuristic algorithm and a multineighborhood simulated annealing algorithm. In addition, we propose a adverse event classification method and a knowledge visualization solution for the information objectification in personalized project
Le traitement, l'interprétation et l'exploitation d'images sonar à antenne synthétique obtenues à partir de trajectoires répétitives by Vincent Myers( Book )

2 editions published in 2019 in English and held by 2 WorldCat member libraries worldwide

There are many scenarios which call for the surveillance of an underwater scene by means of repeated surveys with high-frequency imaging sonar in order to detect changes which may have occurred during the intervening time interval. With the growing availability of commercial synthetic aperture sonar (SAS) systems it becomes possible to exploit the phase coherence between two complex SAS images in order to detect scene changes which are subtle or even invisible to approaches using only the amplitude of the images. This thesis examines the concept of coherent change detection (CCD) using SAS imagery obtained from separate, repeated passes over the same area. As the images must be processed interferometrically, the challenging problem of co-registration is addressed, with approaches based on image warping as well as renavigation / re-imaging. False alarm reduction techniques are also examined in order to mitigate detections caused by coherence losses which are not attributed to the insertion or removal of targets of interest. The proposed methods are tested on several repeat-pass SAS images collected during experiments at sea, spanning multiple frequency bands and environmental conditions, and show that SAS CCD is not only possible, but also able to detect very subtle scene changes that not observable using standard approaches
Information-theory based measures for image analysis : development of two- and threedimensional entropy measures for image texture evaluation and their application to the biomedical field. by Mirvana Hilal( )

1 edition published in 2020 in English and held by 2 WorldCat member libraries worldwide

Le développement de mesures informatisées pour les applications dans le domaine médical contribue à améliorer la capacité de diagnostic, de pronostic et de suivi.Cela fournit une évaluation objective des données et aide les médecins à prendre des décisions, à identifier les anomalies et, éventuellement, à sauver des vies. Dans ce manuscrit de thèse, nous avons développé des mesures d'entropie basées sur le concept de théorie de l'information. Nous montrons que ces méthodes ont la capacité d'analyser l'irrégularité des images en niveaux de gris, des images couleurs, et enfin des volumes. En plus des tests classiques de validation, des tests spécifiques à chaque méthode ont été mis au point. Nos méthodes ont ainsi été analysées par rapport aux modifications de leurs paramètres initiaux, à leur capacité à quantifier les degrés d'irrégularité et de complexité des images et des volumes à travers une approche multi échelle. Nos algorithmes ont trouvé des applications prometteuses dans l'analyse de texture pour différents cas médicaux : traitement des images de mélanome, de pseudoxanthome élastique et l'analyse de la micro circulation cutanée. En outre, après des résultats concluants sur des images en niveaux de gris, nous avons utilisé l'approche couleurs pour extraire des informations cachées dans les composantes couleurs d'images de dermoscopie. Enfin, pour étendre nos applications médicales, nous avons utilisé nos mesures d'entropie tridimensionnelles et leur approche multi échelle pour étudier des acquisitions volumétriques. Ces méthodes ont permis d'étudier des tomographies, des tomographies haute résolution et des volumes IRM dans des cas cliniques de COVID-19, de fibrose pulmonaire idiopathique et de fibrome utérin, respectivement
Processus de Markov multi-auto-similaires à valeurs dans IRd by Salem Lamine( )

1 edition published in 2019 in French and held by 2 WorldCat member libraries worldwide

This thesis aims at studying all R^d-valued multi-self-similar Markov processes (mssMp's), introduced by Jacobsen and Yor in 2003 in the aim of extending the famous Lamperti transformation to R_+^d -valued processes. A full description of these processes is given and many properties of these processes are proved in this work. In particular, we give in the second chapter the form of their state space,and we show that there is no finite entrance law at 0. We give conditions for these processes to satisfy the Feller property. A Lamperti-type representation is also valid for mssMp's and there is a one-to-one relationship between the set of R^d-valued mssMp's and the set of Markov additive processes with values in {-1,1}^d×R^d. This allowed us to establish, in the third chapter some properties of inversion, duality and conditioning of mssMp's. In particular, we build under some assumptions an excessive function h for a give nmssMp. Then we show that the Doob h-transformis interpreted as the original process conditioned to avoid 0 or to hit 0 continuously. We show also under some reversibility conditions, that mssMp's have the space inversion property
Conception d'architecture de système-de-systèmes à logiciel prépondérant dirigée par les missions by Eduardo Ferreira silva( )

1 edition published in 2018 in English and held by 2 WorldCat member libraries worldwide

The formulation of missions is the starting point to the development of Systems-of-Systems (SoS), being used as a basis for the specification, verification and validation of SoS architectures. Specifying, verifying and validating architectural models for SoS are complex tasks compared to usual systems, the inner complexity of SoS relying specially on emergent behaviors, i.e. features that emerge from the interactions among constituent parts of the SoS which cannot be predicted even if all the behaviors of all parts are completely known. This thesis addresses the synergetic relationship between missions and architectures of software-intensive SoS, giving a special attention to emergent behaviors which are created for achieving formulated missions. We propose a design approach for the architectural modeling of SoS driven by the mission models. In our proposal, the mission model is used to both derive, verify and validate SoS architectures. As first step, we define a formalized mission model, then we generate the structure of the SoS architecture by applying model transformations. Later, when the architect specifies the behavioral aspects of the SoS, we generate concrete SoS architectures that will be verified and validated using simulation-based approaches, in particular regarding emergent behaviors. The verification uses statistical model checking to verify whether specified properties are satisfied, within a degree of confidence. The formalization in terms of a temporal logic and statistical model checking are the formal foundations of the developed approach. A toolset that implements the whole approach was also developed and experimented
Cybersecurity of industrial connected equipment : modeling, detection and temporal performance in the presence of intrusions of cyber-physical systems of the factory 4.0 by Salwa Alem( )

1 edition published in 2021 in English and held by 2 WorldCat member libraries worldwide

Over the past decade, the industry has been the victim of several attacks. This phenomenon of cybercrime is eased with the emergence of I4.0. This fourth industrial revolution is characterized by the convergence of Information Technology and Operation Technology worlds', the huge generated data, the use of Cloud as new storage means and the limits of the security mechanisms. All these factors increase the risk of cyber-attacks in industry. The latter can be protected by several security mechanisms including IDS. IDS give visibility of a system activities which in turn allow a timely detection and response to suspicious events. In literature, exist two IDS approaches types: signatures-based and anomaly-based IDS. This last one is more efficient to detect advanced attacks and it is composed of two other IDS types: specification-based IDS and behavioral-based IDS. In industrial intrusion detection field, the main problematic is how to distinguish an industrial process dysfunction from a real intrusion. In this thesis, the proposed approach deals with this specific point. Consequently, hybridization of two types of anomaly-based IDS remains the most efficient method to distinguish a process dysfunction from a real cyber-attack in order to perform a high intrusion detection precision. Therefore, this thesis proposes a hybrid detection approach composed of a behavioral-based IDS is based on the network traffic analysis' using supervised neural network algorithm which learns the normal behavior of the production line and considers any activity that deviates from this reference behavior as intrusion. A specification-based IDS is based on ISA95 standard allowing the detection of the process anomalies and helps to measure the previously detected attacks impact. And a decision-making system (DMS) which pairs the two previous IDS detection results to determine the anomaly nature. The results of this approach are promising with more accurate detection with fewer false positives
On the modeling and control of extended Timed Event Graphs in dioids by Johannes Trunk( )

1 edition published in 2019 in English and held by 2 WorldCat member libraries worldwide

Various kinds of manufacturing systems can be modeled and analyzed by Timed EventGraphs (TEGs). These TEGs are a particular class of timed Discrete Event Systems (DESs), whose dynamic behavior is characterized only by synchronization and saturation phenomena. A major advantage of TEGs over many other timed DES models is that their earliest behavior can be described by linear equations in some tropical algebra structures called dioids. This has led to a broad theory for linear systems over dioids where many concepts of standard systems theory were introduced for TEGs. For instance, with the (max,+)-algebra linear state-space models for TEGs were established. These linear models provide an elegant way to do performance evaluation for TEGs. Moreover, based on transfer functions in dioids severalcontrol problems for TEGs were addressed. However, the properties of TEGs, and thus the systems which can be described by TEGs, are limited. To enrich these properties, two main extensions for TEGs were introduced. First,Weighted Timed Event Graphs (WTEGs) which, in contrast to ordinary TEGs, exhibit event-variant behaviors. InWTEGs integer weights are considered on the arcs whereas TEGs are restricted to unitary weights. For instance, these integer weights make it straightforward to model a cutting process in a production line. Second, a new kind of synchronization called partial synchronization (PS) was introduced forTEGs. PS is useful to model systems where specific events can only occur in a particular time window. For example, consider a crossroad controlled by a traffic light: the green phase of the traffic light provides a time window in which a vehicle is allowed to cross. Clearly, PS leads to time-variant behavior. As a consequence, WTEGs and TEGs under PS are not (max,+)-linear anymore.In this thesis, WTEGs and TEGs under PS are studied in a dioid structure. Based on these dioid models forWTEGs a decomposition of the dynamic behavior into an event-variant and an event-invariant part is proposed. Under some assumptions, it is shown that the eventvariant part is invertible. Hence, based on this model, optimal control and model reference control, which are well known for ordinary TEGs, are generalized to WTEGs. Similarly, a decomposition model is introduced for TEGs under PS in which the dynamic behavior is decomposed into a time-variant and time-invariant part. Again, under some assumptions, it is shown that the time-variant part is invertible. Subsequently, optimal control, as well as model reference control for TEGs under PS is addressed
moreShow More Titles
fewerShow Fewer Titles
Audience Level
Audience Level
  General Special  
Audience level: 0.89 (from 0.88 for Cybersecur ... to 0.92 for Unicité e ...)

Alternative Names
École doctorale 601

École doctorale MATHSTIC

ED 601



Université Bretagne Loire (France). École doctorale Mathématiques et sciences et technologies de l'information et de la communication

English (16)

French (8)