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Set-Valued Koopman Theory for Control Systems
No full textInternational audienceIn this paper, we introduce a new notion of Koopman operator which faithfully encodes the dynamics of controlled systems by leveraging the grammar of set-valued analysis. In this context, we propose meaningful generalisations of the Liouville and Perron-Frobenius operators, and show that they respectively coincide with proper set-valued analogues of the infinitesimal generator and dual operator of the Koopman semigroup. We also give meaning to the spectra of these set-valued maps and prove an adapted version of the classical spectral mapping theorem relating the eigenvalues of a semigroup and those of its generator. In essence, these results provide theoretical justifications for existing approaches in the Koopman communities which consist in studying control systems by bundling together the Liouville operators associated with different input parameters
Atomic-Layer-Deposited Aluminum Oxide (Al2O3) as a Barrier for Local Oxidation of Silicon
No full textThe LOCal Oxidation of Silicon (LOCOS) is a widely used technological process that conventionally exploits hundreds-of-nanometer-thick silicon nitride (SiN) layers as the mask to locally prevent the silicon surface to be oxidized. Here, investigations of the use of ultrathin (<20-nm) Al2O3 layers grown by Atomic Layer Deposition (ALD) as material-sparing alternative to SiN are reported. A significant reduction the oxidation rate by a factor greater than 15 is demonstrated for either dry thermal and plasma oxidations, paving the way towards more environmentally-sustainable LOCOS processes for the fabrication of microelectronic and photonic devices
Optimal Preconditioning Voltages for SiC MOSFET Vth Measurement in the Aim of Temperature Measurement
No full textInternational audienceThis paper deals with SiC MOSFET preconditioning techniques with the aim of using Vth measurement as a reliable thermally sensitive electrical parameter (TSEP). In particular, the efficiency of the different preconditioning processes is studied for different stress voltages and temperatures applied to the MOSFET. The time constant of the trapping phenomenon is globally revealed by measurements of the Vth shift over time. This leads to choosing the preconditioning carefully
Detection of EGFR mutations at pM concentration in ten minutes using a microfluidic concentration and separation module
No full textThe authors would like to thank FEDER-FSE Midi-Pyrénées et Garonne 2014-2020 for financial supportInternational audienceAbstract Epidermal growth factor receptor (EGFR) mutation detection is now commonly used in the management of cancer patients, particularly those diagnosed with non-small cell lung cancer. Molecular beacon-based sensing is direct and rapid, but its sensitivity is low. Conversely, high-sensitivity detection methodologies based on amplification are robust and sensitive but are limited by relatively require long turnaround times. In this study, we utilized a size-resolved, molecular beacon-based strategy for the rapid detection of EGFR genomic alterations, specifically exon 19 deletions and L858R point mutation. This technology combines a concentration and separation module, which allows us to successfully demonstrate the detection of deletions and point mutations of EGFR in five minutes with a mutant allele sensitivity of 10%. The use of a dual-color detection insures fast detection with a reduced risk of false positives. This work represents a first step toward the fast and specific detection of genetic mutations to improve the management of patients with hard-to-treat tumors
Towards Context-aware Intrusion Detection in Individual-oriented Information Systems: An Empirical Study on Android Malware
No full textInternational audienceIn recent years, the range and volume of Internet services utilized by an individual have significantly expanded. This growing relationship between an individual user and diverse digital services has led to the emergence of Individualoriented Information System (IIS) that encompasses the user, their physical devices, and the information systems they interact with. Current security approaches within an IIS suffer from three main limitations: (1) they are restricted to specific services, (2) they require intrusive instrumentation of each user single device, or (3) they rely on specific integration between client and server components. As a result, they fail to globally protect against attackers who possess enough information to bypass standalone security schemes. To overcome these constraints, we propose to (1) consider a network-oriented approach to detect intrusions which may occur within an IIS and (2) to make sensors taking part of the IIS contribute to the intrusion detection by providing user-related contextual data. In the absence of any suitable dataset that mixes network and physical contextual data, we construct a new integrated dataset comprising benign data captured through an in-situ experiment and intrusion traces extracted from CIC-AndMal2017-a widely referenced dataset in the literature. Our evaluation confirms that consider both user physical context and network features improves the performance of intrusion detection, thereby making IIS more resilient to attackers
Graph-Based Product Form
No full textProduct-form stationary distributions in Markov chains have been a foundational advance and driving force in our understanding of stochastic systems. In this paper, we introduce a new product-form relationship that we call "graph-based product form". As our first main contribution, we prove that two states of the Markov chain are in graph-based product form if and only if the following two equivalent conditions are satisfied: (i) a cut-based condition, reminiscent of classical results on product-form queueing systems, and (ii) a novel characterization that we call joint-ancestor freeness. The latter characterization allows us in particular to introduce a graph-traversal algorithm that checks product-form relationships for all pairs of states, with time complexity , if the Markov chain has a finite transition graph . We then generalize graph-based product form to encompass more complex relationships, which we call "higher-level product form", and we again show these can be identified via a graph-traversal algorithm when the Markov chain has a finite state space. Lastly, we identify several examples from queueing theory that satisfy this product-form relationship
D2.1 Edge solutions requirements and specification
No full textInternational audienceThis document, D2.1 – Edge Solutions Requirements and Specification, establishes the framework for the development of the E2CC Orchestrator, the pivotal instrument that will oversee resources across the cloud-to-edge continuum.As more services move closer to users and devices, there is an increasing need to coordinate computing and data in smart, secure and efficient ways. This is precisely what the orchestrator is designed to do. The text opens with an explanation of why we need to move beyond traditional cloud setups. The proliferation of connected devices, real-time applications, and mounting privacy concerns necessitate a shift away from reliance on centralized infrastructure.Instead, the focus should be on implementing flexible systems capable of handling data andworkloads in the most efficient manner, whether that be in the cloud, at the edge, or in a hybrid model. The deliverable provides a comprehensive overview of the orchestrator's key features, including its approach to onboarding resources, deploying applications, managing AI workloads, and ensuring security and observability.These needs are then broken down into detailed user stories and translated into clear systemrequirements. All tasks are prioritised using a structured method (MoSCoW), enabling the team to focus on the most important items.It also demonstrates the orchestrator's role within broader European initiatives, such as theIPCEI-CIS Reference Architecture, and presents the technical building blocks that will underpinit — including APIs, workflow engines, monitoring systems and support for confidential computing.In summary, this document specifies the requirements for the E2CC Orchestrator and itsconstruction, thereby establishing a framework for the subsequent phases of the project
Hybrid extended cavity laser made of silicon nitride Bragg gratings and GaAs optical amplifiers for frequency comb generation around 965 nm
No full textInternational audienceWe present the characterisation of a silicon nitride chip that includes a Bragg reflector, which, butt-coupled to a Reflective Semiconductors Optical Amplifier, will form an extended cavity laser emitting around 965nm for generating a frequency comb
Experimental Investigation and Behavioral Modeling of the Ron vs. Gate Overshoots Relationship in Schottky p-GaN HEMTs
No full textInternational audienceThe semi-floating p-GaN layer of commercial schottky HEMTs is suspected to be related to instabilities of the device's electrical characteristics. Particularly, we recently explained how gate voltage spikes at turn-on can cause a drastic, lasting and reproducible dynamic Ron increase. The proposed explanation only partly matched the dynamics of the observed Ron fluctuations and only one device reference was tested. In this work, higher voltage spikes are explored and a device from an other manufacturer is also studied. We demonstrate with a ngspice simulation how all observed dynamic Ron behaviors can be explained with a two-diode model of the gate stack