Search results for "Cryptography"
showing 10 items of 657 documents
On codimension two embeddings up to link-homotopy
2017
We consider knotted annuli in 4-space, called 2-string-links, which are knotted surfaces in codimension two that are naturally related, via closure operations, to both 2-links and 2-torus links. We classify 2-string-links up to link-homotopy by means of a 4-dimensional version of Milnor invariants. The key to our proof is that any 2-string link is link-homotopic to a ribbon one; this allows to use the homotopy classification obtained in the ribbon case by P. Bellingeri and the authors. Along the way, we give a Roseman-type result for immersed surfaces in 4-space. We also discuss the case of ribbon k-string links, for $k\geq 3$.
Federated Learning for Zero-Day Attack Detection in 5G and Beyond V2X Networks
2023
Deploying Connected and Automated Vehicles (CAVs) on top of 5G and Beyond networks (5GB) makes them vulnerable to increasing vectors of security and privacy attacks. In this context, a wide range of advanced machine/deep learning-based solutions have been designed to accurately detect security attacks. Specifically, supervised learning techniques have been widely applied to train attack detection models. However, the main limitation of such solutions is their inability to detect attacks different from those seen during the training phase, or new attacks, also called zero-day attacks. Moreover, training the detection model requires significant data collection and labeling, which increases th…
Système de sécurité biométrique multimodal par imagerie, dédié au contrôle d’accès
2019
Research of this thesis consists in setting up efficient and light solutions to answer the problems of securing sensitive products. Motivated by a collaboration with various stakeholders within the Nuc-Track project, the development of a biometric security system, possibly multimodal, will lead to a study on various biometric features such as the face, fingerprints and the vascular network. This thesis will focus on an algorithm and architecture matching, with the aim of minimizing the storage size of the learning models while guaranteeing optimal performances. This will allow it to be stored on a personal support, thus respecting privacy standards.
Scheduling independent stochastic tasks under deadline and budget constraints
2018
This article discusses scheduling strategies for the problem of maximizing the expected number of tasks that can be executed on a cloud platform within a given budget and under a deadline constraint. The execution times of tasks follow independent and identically distributed probability laws. The main questions are how many processors to enroll and whether and when to interrupt tasks that have been executing for some time. We provide complexity results and an asymptotically optimal strategy for the problem instance with discrete probability distributions and without deadline. We extend the latter strategy for the general case with continuous distributions and a deadline and we design an ef…
THE IMAGE PROTECTOR A Flexible Security Rule Specification Toolkit
2011
International audience; The tremendous sharing of multimedia objects on the web shed the light on several privacy concerns related in essence to the safe publishing of end users' personal data. Providing techniques to protect multimedia objects faces several difficulties due to multimedia objects' heterogeneous and complex structure on one hand, and on the other hand, the wide range of information that could be used to describe their content. In this paper, we present a flexible security rule specification toolkit for multimedia objects. Our toolkit is based on a security model and a core ontology in which we populate the model's related information and multimedia objects data. To specify s…
Automated detection of contextuality proofs with intermediate numbers of observables
2021
<div style=""><font face="arial, helvetica"><span style="font-size: 13px;">Quantum contextuality takes an important place amongst the concepts of quantum computing that bring an advantage over its classical counterpart. For a large class of contextuality </span></font><span style="font-size: 13px; font-family: arial, helvetica;">proofs, aka. observable-based proofs of the Kochen-Specker Theorem, we first formulate the</span></div><div style=""><font face="arial, helvetica"><span style="font-size: 13px;">contextuality property as the absence of solutions to a linear system. Then we explain why </span></font><span style="font-size: 13px; font-family: arial, helvetica…
A Route toward Protein Sequencing using Solid-State Nanopores Assisted by Machine Learning
2022
Solid-State Nanopores made of 2-D materials such as MoS2 have emerged as one of the most versatile sensors for single-biomolecule detection, which is essential for early disease diagnosis (biomarker detection). One of the most promising applications of SSN is DNA and protein sequencing, at a low cost and faster than the current standard methods. The detection principle relies on measuring the relatively small variations of ionic current as charged biomolecules immersed in an electrolyte traverse the nanopore, in response to an external voltage applied across the membrane. The passage of a biomolecule through the pore yields information about its structure and chemical properties, as demonst…
Computer-assisted enumeration and classification of multi-qubit doilies
2022
For N ≥ 2, an N-qubit doily is a doily living in the N-qubit symplectic polar space. These doilies are related to operator-based proofs of quantum contextuality. Following and extending the strategy of [SdBHG21] that focused exclusively on three-qubit doilies, we first bring forth several formulas giving the number of both linear and quadratic doilies for any N > 2. Then we present an effective algorithm for the generation of all N-qubit doilies. Using this algorithm for N = 4 and N = 5, we provide a classification of N-qubit doilies in terms of types of observables they feature and number of negative lines they are endowed with.
Non-commutative Ring Learning with Errors from Cyclic Algebras
2022
AbstractThe Learning with Errors (LWE) problem is the fundamental backbone of modern lattice-based cryptography, allowing one to establish cryptography on the hardness of well-studied computational problems. However, schemes based on LWE are often impractical, so Ring LWE was introduced as a form of ‘structured’ LWE, trading off a hard to quantify loss of security for an increase in efficiency by working over a well-chosen ring. Another popular variant, Module LWE, generalizes this exchange by implementing a module structure over a ring. In this work, we introduce a novel variant of LWE over cyclic algebras (CLWE) to replicate the addition of the ring structure taking LWE to Ring LWE by add…
A novel linear friction welding based approach for sheet-bulk joining
2019
In the last decades, the development of new, flexible manufacturing processes caused the increase of the demands for highly customized complex functional parts in many industrial fields. The peculiar design of these components often overcome conventional sheet metal and bulk metal forming processes capabilities. In order to face this issue, new hybrid techniques, capable of exploit key advantages of different processes, have to be developed. In this paper, a novel approach based on the Linear Friction Welding process is proposed to obtain sheet-bulk joints. The feasibility of the technique on high specific strength alloys is investigated through an experimental campaign.In the last decades,…