La maitrise de la complexité croissante tant de nos organisations socioéconomiques que de nos systèmes et infrastructures technologiques, impose des systèmes informatiques de plus en plus intégrés. L’organisation de nos sociétés avancées ne pourrait plus se développer dans des conditions raisonnables sans le support des technologies de l’information. Les différents systèmes d’information s’intègrent ainsi de plus en plus en un maillage informationnel formant ainsi un système de systèmes qui se complexifie de jour en jour et de ce fait devient de plus en plus vital. Ces systèmes des systèmes doivent répondre à deux types d’objectifs : i) la réalisation d’un système par l’intégration de systèmes offerts par différents fournisseurs, ii) l’interopération de systèmes déjà en service en vue d’obtenir des propriétés nouvelles dues à leur coopération, généralement avec une augmentation d’efficacité. Ces objectifs et cette complexité ne peuvent être appréhendés par une démarche purement analytique. C’est pourquoi nous avons préconisé à travers cette thèse une solution de système de systèmes basée sur un graphe d'interopérabilité construit sur une comparaison hiérarchique ontologique. La mise en œuvre de cette approche à travers l’utilisation d’une plateforme d’agents mobile permet une recherche dynamique de services visant à satisfaire au mieux les critères de qualité exigés par l’utilisateur. / Mastering the increasing complexity of our socio-economic organizations and technology infrastructure requires more and more integrated information systems. The organization of our advanced societies could no longer grow on reasonable terms without the support of information technology.The different information systems belongs more and more to an informational meshing, forming in this way a complex system of systems which is getting complex day after day and because of that is becoming increasingly vital.This system of systems must meet two objectives: i) implementation of a system by integrating systems offered by different providers, ii) interoperation of systems already in use in order to obtain new properties due to their cooperation, usually with an efficiency increase.These objectives and this complexity can be grasped by a purely analytical approach. That is why we have advocated throughout this thesis a solution of system of systems based on an interoperability graph built on a hierarchical ontological comparison (foundation of trust). The platform of mobile agents associated with this system will implement a dynamic search of services which tries to satisfy the quality criteria required by the user.

The growth of technology and the proliferation of information made modern complex systems more fragile and vulnerable. As a result, competitive advantage is no longer achieved exclusively through strategic planning but by developing an influential cadre of technical people who can efficiently manage and navigate modern complex systems. The dissertation aims to provide educators, practitioners, and organizations with a model that helps to measure individuals’ systems thinking skills, complex problem solving, personality traits, and the impacting demographic factors such as managerial and work experience, current occupation type, organizational ownership structure, and education level. The intent is to study how these skills, traits, and demographic factors can impact an individual’s abilities in working effectively with modern complex systems. These skills and traits also enable individuals to display distinctive patterns of thoughts in developing solutions that address complex technical problems. The dissertation further provides strategies for the management and enhancement of technical individuals based on assessing their performance. The model consists of three established instruments: Systems Thinking Skills, Perceived Complex Problem-Solving (PCPS), and Myers-Briggs Personality Type Indicator. These instruments are applied at the individual level to identify strengths and weak areas of improving an organization. In particular, PCPS is a researcher-developed instrument that captures the complex problem-solving perception of individuals. The different samples of the population for the dissertation come from students and practitioners.

Organized cybercrime has no borders in cyberspace. This paper suggests a state-of-the-art architected solution for a global Automated cross-border mutual legal assistance system within Digital Forensic (AUTOMLA). The Enterprise framework with technical viewpoint enables international collaboration between sovereign countries Fusion Centers. The evaluation concludes a user interface built in React, middleware Apollo with schema support linked to graph database Neo4j. GraphQL is the preferred application protocol over REST. Fusion Centers API is deployed as federated gateways, and business functions are implemented as PaaS serverless services.  Its intuitive modeling Forensics in graphs, semantic networks enables causality and inference. All suggested elements in AUTOMLA are forming an internationally agreed collaborative platform; the solution for fast cross-border crime investigations. AUTOMLA deployed on the Internet is a subject for threats. Risks are mitigated in design guided by security frameworks. The recommended development method is agile, distributed in between autonomous teams.

Increasingly flexible and efficient industrial processes and automation systems are developed by integrating computational systems and physical processes, thereby forming large heterogeneous systems of cyber-physical systems. Such systems depend on particular data models and payload formats for communication, and making different entities interoperable is a challenging problem that drives the engineering costs and time to deployment. Interoperability is typically established and maintained manually using domain knowledge and tools for processing and visualization of symbolic metadata, which limits the scalability of the present approach. The vision of next generation automation frameworks, like the Arrowhead Framework, is to provide autonomous interoperability solutions. In this thesis the problem to automatically establish interoperability between cyber-physical systems is reviewed and formulated as a mathematical optimisation problem, where symbolic metadata and message payloads are combined with machine learning methods to enable message translation and improve system of systems utility. An autoencoder based implementation of the model is investigated and simulation results for a heating and ventilation system are presented, where messages are partially translated correctly by semantic interpolation and generalisation of the latent representations. A maximum translation accuracy of 49% is obtained using this unsupervised learning approach. Further work is required to improve the translation accuracy, in particular by further exploiting metadata in the model architecture and autoencoder training protocol, and by considering more advanced regularization methods and utility optimization. / Productive 4.0

Les systèmes neuromusculaire et musculosquelettique sont des systèmes de systèmes complexes qui interagissent parfaitement entre eux afin de produire le mouvement. En y regardant de plus près, ce mouvement est la résultante d'une force musculaire créée à partir d'une activation du muscle par le système nerveux central. En parallèle de cette activité mécanique, le muscle produit aussi une activité électrique elle aussi contrôlée par la même activation. Cette activité électrique peut être mesurée à la surface de la peau à l'aide d'électrode, ce signal enregistré par l'électrode se nomme le signal Électromyogramme de surface (sEMG). Comprendre comment ces résultats de l'activation du muscle sont générés est primordial en biomécanique ou pour des applications cliniques. Évaluer et quantifier ces interactions intervenant durant la contraction musculaire est difficile et complexe à étudier dans des conditions expérimentales. Par conséquent, il est nécessaire de développer un moyen pour pouvoir décrire et estimer ces interactions. Dans la littérature de la bioingénierie, plusieurs modèles de génération de signaux sEMG et de force ont été publiés. Ces modèles sont principalement utilisés pour décrire une partie des résultats de la contraction musculaire. Ces modèles souffrent de plusieurs limites telles que le manque de réalisme physiologique, la personnalisation des paramètres, ou la représentativité lorsqu'un muscle complet est considéré. Dans ce travail de thèse, nous nous proposons de développer un modèle biofidèle, personnalisable et rapide décrivant l'activité électrique et mécanique du muscle en contraction isométrique. Pour se faire, nous proposons d'abord un modèle décrivant l'activité électrique du muscle à la surface de la peau. Cette activité électrique sera commandé par une commande volontaire venant du système nerveux périphérique, qui va activer les fibres musculaires qui vont alors dépolariser leur membrane. Cette dépolarisation sera alors filtrée par le volume conducteur afin d'obtenir l'activité électrique à la surface de la peau. Une fois cette activité obtenue, le système d'enregistrement décrivant une grille d'électrode à haute densité (HD-sEMG) est modélisée à la surface de la peau afin d'obtenir les signaux sEMG à partir d'une intégration surfacique sous le domaine de l'électrode. Dans ce modèle de génération de l'activité électrique, le membre est considéré cylindrique et multi couches avec la considération des tissus musculaire, adipeux et la peau. Par la suite, nous proposons un modèle mécanique du muscle décrit à l'échelle de l'Unité Motrice (UM). L'ensemble des résultats mécaniques de la contraction musculaire (force, raideur et déformation) sont déterminées à partir de la même commande excitatrice du système nerveux périphérique. Ce modèle est basé sur le modèle de coulissement des filaments d'actine-myosine proposé par Huxley que l'on modélise à l'échelle UM en utilisant la théorie des moments utilisée par Zahalak. Ce modèle mécanique est validé avec un profil de force enregistré sur un sujet paraplégique avec un implant de stimulation neurale. Finalement, nous proposons aussi trois applications des modèles proposés afin d'illustrer leurs fiabilités ainsi que leurs utilité. Tout d'abord une analyse de sensibilité globale des paramètres de la grille HDsEMG est présentée. Puis, nous présenterons un travail fait en collaboration avec une autre doctorante une nouvelle étude plus précise sur la modélisation de la relation HDsEMG/force en personnalisant les paramètres afin de mimer au mieux le comportement du Biceps Brachii. Pour conclure, nous proposons un dernier modèle quasi­ dynamique décrivant l'activité électro-mécanique du muscle en contraction isométrique. Ce modèle déformable va actualiser l'anatomie cylindrique du membre sous une hypothèse isovolumique du muscle. / The neuromuscular and musculoskeletal systems are complex System of Systems (SoS) that perfectly interact to provide motion. From this interaction, muscular force is generated from the muscle activation commanded by the Central Nervous System (CNS) that pilots joint motion. In parallel an electrical activity of the muscle is generated driven by the same command of the CNS. This electrical activity can be measured at the skin surface using electrodes, namely the surface electromyogram (sEMG). The knowledge of how these muscle out comes are generated is highly important in biomechanical and clinical applications. Evaluating and quantifying the interactions arising during the muscle activation are hard and complex to investigate in experimental conditions. Therefore, it is necessary to develop a way to describe and estimate it. In the bioengineering literature, several models of the sEMG and the force generation are provided. They are principally used to describe subparts of themuscular outcomes. These models suffer from several important limitations such lacks of physiological realism, personalization, and representability when a complete muscle is considered. In this work, we propose to construct bioreliable, personalized and fast models describing electrical and mechanical activities of the muscle during contraction. For this purpose, we first propose a model describing the electrical activity at the skin surface of the muscle where this electrical activity is determined from a voluntary command of the Peripheral Nervous System (PNS), activating the muscle fibers that generate a depolarization of their membrane that is filtered by the limbvolume. Once this electrical activity is computed, the recording system, i.e. the High Density sEMG (HD-sEMG) grid is define over the skin where the sEMG signal is determined as a numerical integration of the electrical activity under the electrode area. In this model, the limb is considered as a multilayered cylinder where muscle, adipose and skin tissues are described. Therefore, we propose a mechanical model described at the Motor Unit (MU) scale. The mechanical outcomes (muscle force, stiffness and deformation) are determined from the same voluntary command of the PNS, and is based on the Huxley sliding filaments model upscale at the MU scale using the distribution-moment theory proposed by Zahalak. This model is validated with force profile recorded from a subject implanted with an electrical stimulation device. Finally, we proposed three applications of the proposed models to illustrate their reliability and usefulness. A global sensitivity analysis of the statistics computed over the sEMG signals according to variation of the HD-sEMG electrode grid is performed. Then, we proposed in collaboration a new HDsEMG/force relationship, using personalized simulated data of the Biceps Brachii from the electrical model and a Twitch based model to estimate a specific force profile corresponding to a specific sEMG sensor network and muscle configuration. To conclude, a deformableelectro-mechanicalmodelcouplingthetwoproposedmodelsisproposed. This deformable model updates the limb cylinder anatomy considering isovolumic assumption and respecting incompressible property of the muscle.

Gegenstand dieser Arbeit ist die Untersuchung generischer Synchronisierungsphänomene in interagierenden komplexen Systemen. Diese Phänomene werden u.a. in gekoppelten deterministischen chaotischen Systemen beobachtet. Bei sehr schwachen Interaktionen zwischen individuellen Systemen kann ein Übergang zum schwach kohärenten Verhalten der Systeme stattfinden. In gekoppelten zeitkontinuierlichen chaotischen Systemen manifestiert sich dieser Übergang durch den Effekt der Phasensynchronisierung, in gekoppelten chaotischen zeitdiskreten Systemen durch den Effekt eines nichtverschwindenden makroskopischen Feldes.<br /> Der Übergang zur Kohärenz in einer Kette lokal gekoppelter Oszillatoren, beschrieben durch Phasengleichungen, wird im Bezug auf die Symmetrien des Systems untersucht. Es wird gezeigt, daß die durch die Symmetrien verursachte Reversibilität des Systems nichttriviale topologische Eigenschaften der Trajektorien bedingt, so daß das als dissipativ konstruierte System in einem ganzen Parameterbereich quasi-Hamiltonische Züge aufweist, d.h. das Phasenvolumen ist im Schnitt erhalten, und die Lyapunov-Exponenten sind paarweise symmetrisch.<br /> Der Übergang zur Kohärenz in einem Ensemble global gekoppelter chaotischer Abbildungen wird durch den Verlust der Stabilität des entkoppelten Zustandes beschrieben. Die entwickelte Methode besteht darin, die Selbstkonsistenz des makroskopischen Feldes aufzuheben, und das Ensemble in Analogie mit einem Verstärkerschaltkreis mit Rückkopplung durch eine komplexe lineare Übertragungssfunktion zu charakterisieren.<br /> Diese Theorie wird anschließend für einige theoretisch interessanten Fälle verallgemeinert. / Subject of this work is the investigation of generic synchronization phenomena in interacting complex systems. These phenomena are observed, among all, in coupled deterministic chaotic systems. At very weak interactions between individual systems a transition to a weakly coherent behavior of the systems can take place. In coupled continuous time chaotic systems this transition manifests itself with the effect of phase synchronization, in coupled chaotic discrete time systems with the effect of non-vanishing macroscopic mean field.<br /> Transition to coherence in a chain of locally coupled oscillators described with phase equations is investigated with respect to the symmetries in the system. It is shown that the reversibility of the system caused by these symmetries results to non-trivial topological properties of trajectories so that the system constructed to be dissipative reveals in a whole parameter range quasi-Hamiltonian features, i.e. the phase volume is conserved on average and Lyapunov exponents come in symmetric pairs.<br /> Transition to coherence in an ensemble of globally coupled chaotic maps is described with the loss of stability of the disordered state. The method is to break the self-consistensy of the macroscopic field and to characterize the ensemble in analogy to an amplifier circuit with feedback with a complex linear transfer function.<br /> This theory is then generalized for several cases of theoretic interest.

Management and supply of water in an urban water distribution system is a complex process, which include various complexities like pressure variations across the network depending on topography, demand variations depending on customers’ requirement and unaccounted water etc. Applying automatic control methods to water distribution systems is a way to improve the management of water distribution. There have been some attempts in recent years to develop optimal control algorithms to assist in the operation of complex water distribution systems. The difficulties involved by these hydraulic systems such as non-linearity, and diurnal demand patterns make the choice of a suitable automatic control method a challenge. For this purpose, this study intends to investigate the applicability of different controllers which would be able to meet the targets as quickly as possible and without creating undue transients. As a first step towards application of different controllers, PD and PID linear controllers have been designed for pump control and valve control in water distribution systems. Then a Dynamic Inversion based nonlinear controller has been designed by considering the non-linearities in the system. Here, different cases considering the effects of initial conditions used, linearization methods used, time step used for integration and selection of gains etc., have been studied before arriving at best controller. These controllers have been designed for both the flow control problems and level control problems. It is found that Dynamic Inversion-based nonlinear controller outperforms other controllers. It is well known that the performance of controllers is much dependent on the tuning of the gains (parameters). Thus in this study various alternative techniques such as Ziegler--Nichols rules (ZNPID), Genetic algorithms (GAPID) and fuzzy algorithms (FZPID) have been studied and a comparative study has been made Although with all the three gain tuning methods, required states have reached their target values, but the responses vary much in reaching to final targets. The self-tuned FZPID controller outperforms other two controllers, especially with regard to overshoots and the time taken to tune the gains for each problem. Further, an optimal DI controller is developed for the over determined case with more controls and less targets. Energy loss is considered as an objective function and normal DI controller equations are considered as constraints. Hence, an attempt is made to reduce the energy minimization in water distribution system by formulating an optimal control problem using optimal Dynamic Inversion concept. Finally, leakage reduction model is developed based on excessive pressure minimization problem by locating valves optimally as well as by setting valves optimally. For this purpose, optimization problem is solved using Pattern search algorithms and hydraulic analysis is carried out using EPANET program.

A system of systems (SoS) framework is proposed for policy design that takes into account the value systems of multiple participants, harnesses the complexity of strategic interactions among participants, and confronts the risks and uncertainties present in participants’ decision making. SoS thinking provides an integrative and adaptive mindset, which is needed to tackle policy challenges characterized by conflict, complexity, and uncertainty. With the aim of putting SoS thinking into practice, operational methods and tools are presented herein. Specifically, SoS engineering methodologies to create value system models, agent-based models of competitive and cooperative behaviour under conflict, and risk management models are developed and integrated into the framework. The proposed structure, methods and tools can be utilized to organize policy design discourse. Communication among participants involved in the policy discussion is structured around SoS models, which are used to integrate multiple perspectives of a system and to test the effectiveness of policies in achieving desirable outcomes under varying conditions. In order to demonstrate the proposed methods and tools that have been developed to enliven policy design discourse, a theoretical common-pool resources dilemma is utilized. The generic application illustrates the methodology of constructing ordinal preferences from values. Also, it is used to validate the agent-based modeling and simulation platform as a tool to investigate strategic interactions among participants and harness the potential to influence and enable participants to achieve desirable outcomes. A real-world common pool resources dilemma in the provisioning and security considerations of the Straits of Malacca and Singapore is examined and employed as a case study for applying strategic conflict models in risk management. Overall, this thesis advances the theory and application of SoS engineering and focuses on understanding value systems, handling complexity in terms of conflict dynamics, and finally, enhancing risk management.

A system of systems (SoS) framework is proposed for policy design that takes into account the value systems of multiple participants, harnesses the complexity of strategic interactions among participants, and confronts the risks and uncertainties present in participants’ decision making. SoS thinking provides an integrative and adaptive mindset, which is needed to tackle policy challenges characterized by conflict, complexity, and uncertainty. With the aim of putting SoS thinking into practice, operational methods and tools are presented herein. Specifically, SoS engineering methodologies to create value system models, agent-based models of competitive and cooperative behaviour under conflict, and risk management models are developed and integrated into the framework. The proposed structure, methods and tools can be utilized to organize policy design discourse. Communication among participants involved in the policy discussion is structured around SoS models, which are used to integrate multiple perspectives of a system and to test the effectiveness of policies in achieving desirable outcomes under varying conditions. In order to demonstrate the proposed methods and tools that have been developed to enliven policy design discourse, a theoretical common-pool resources dilemma is utilized. The generic application illustrates the methodology of constructing ordinal preferences from values. Also, it is used to validate the agent-based modeling and simulation platform as a tool to investigate strategic interactions among participants and harness the potential to influence and enable participants to achieve desirable outcomes. A real-world common pool resources dilemma in the provisioning and security considerations of the Straits of Malacca and Singapore is examined and employed as a case study for applying strategic conflict models in risk management. Overall, this thesis advances the theory and application of SoS engineering and focuses on understanding value systems, handling complexity in terms of conflict dynamics, and finally, enhancing risk management.

During neocortical development, network activity undergoes a dramatic transition from largely synchronized, so-called cluster activity, to a relatively sparse pattern around the time of eye-opening in rodents. Biophysical mechanisms underlying this sparsification phenomenon remain poorly understood. Here, we present a dynamic systems modeling study of a developing neural network that provides the first mechanistic insights into sparsification. We find that the rest state of immature networks is strongly affected by the dynamics of a transient, unstable state hidden in their firing activities, allowing these networks to either be silent or generate large cluster activity. We address how, and which, specific developmental changes in neuronal and synaptic parameters drive sparsification. We also reveal how these changes refine the information processing capabilities of an in vivo developing network, mainly by showing a developmental reduction in the instability of network’s firing activity, an effective availability of inhibition-stabilized states, and an emergence of spontaneous attractors and state transition mechanisms. Furthermore, we demonstrate the key role of GABAergic transmission and depressing glutamatergic synapses in governing the spatiotemporal evolution of cluster activity. These results, by providing a strong link between experimental observations and model behavior, suggest how adult sparse coding networks may emerge developmentally.