Publications Internationales
Permanent URI for this collectionhttps://dspace.univ-boumerdes.dz/handle/123456789/13
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Item A Formalized procedure for database horizontal fragmentation in isabelle/HOL Proof Assistant(Springer, 2018) Cheikh, Salmi; Chaabani, Mohamed; Mezghiche, MohamedWe propose a logical procedure for the horizontal fragmentation problem based on predicate abstraction over the entire domain of database relations. The set of minterm predicates is constructed using rewriting rules similar to the well-known semantic tableau algorithm. The procedure start from an initial set of simple predicates, build the set of minterm predicates until rules are no longer required. To ensure this proposition, we give a formal proof of its correctness namely, it’s soundness, completeness and termination with Isabelle proof assistant. The main contribution of this work are: refining the minterm approach by adding a semantic layer to predicates, minimizing the set of minterm predicates by automatically eliminating contradictory ones, detecting and handling subsumptions between them. This leads to the best construction time of the final partitioning schema. Finally, a source code of the procedure is generated automatically by the Isabelle proof assistant.Item Towards compositional verification of synchronous reactive systems(2021) Chabane, Sarah; Ameur-Boulifa, Rabéa; Mezghiche, MohamedWe present work towards a compositional design approach that will lead designers to develop safe reactive systems. To this end, we extend the theory of I/O-automata that is widely used for modelling reactive systems with composition operator required for dealing with a specific assembly of such systems: systems that consist of a chain of components arranged so that the output of each component is the input of the next, and behave like pipelines. We show that the proposed composition operator ensures semantics preserving of reactive components models. The paper presents a general result on correct-by-construction approach for reactive systems designItem A practical approach for verification of graph transformation with description logic(2020) Chaabani, Mohamed; Mezghiche, MohamedGraphs and visual models play a central role in the modeling and meta-modeling of software systems, these models are specified using a modeling formalism, in a high-level abstraction independent of the platform, in which the focus is on the concepts rather than the implementation. This allows keeping the model, transporting it, and then transforming it into code. Several graph transformation tools have been developed to ensure efficient transformations. This transformation requires a process of verification and validation to guarantee the correction of this transformation process, of which there are different ways to checking that a software system achieves its goal. In computer science, formal methods are techniques that allow rigorous reasoning, using semantic and formal methods, to prove their validity with respect to a certain set of properties. In this sense, description logics are promising candidates for encoding graph structures and reasoning about graph transformations, they are privileged target to operationalize graph transformation tools because they have the mechanisms of reasoning or inferenceItem Exploiting links to improve search in XML documents(Digital Information Research Foundation, 2018) Berchiche-Fellag, Samia; Mezghiche, MohamedThis paper describes an approach that ex-ploits links in XML retrieval. The proposed approach con-sists of reranking the set of documents returned for agiven query by considering three sources of evidencenamely, the relevance scores w.r.t query of a documentneighbours, the text of the anchor links, and the docu-ment title tag. Our approach is evaluated on INEX 2006collection. The results showed significant improvementsof the retrieval performancesItem A new AOMDV lifetime prolonging routing algorithm for Ad-Hoc networks(IGI Global, 2019) Baddari, Ibtihel; Riahla, Mohamed Amine; Mezghiche, MohamedNetwork lifetime is a key design metric in MANETs, it is considered as one of the most important parametersalgorithmstobeusedinadhocnetworks.Eachnetworknodeworkscompletely independently and acts as a router for relaying communications. If some nodes die prematurely because of battery depletion, the network lifetime will be adversely affected, and the network will get disconnected. This article presents AOMDV-LP, a new AOMDV lifetime-prolonging routing algorithm for MANETs. This new algorithm helps to maximize the network lifetime by managing nodesenergy,linkcostandcontrollingthenetworkscongestion.Simulationsquantifytheperformance gains of the authors algorithmItem Hiding a fault enabled virus through code construction(2020) Hamadouche, Samiya; Lanet, Jean-Louis; Mezghiche, MohamedSmart cards are very secure devices designed to execute applica-tions and store confidential data. Therefore, they become the target of manyhardware and software attacks that aim to bypass their embedded securitymechanisms in order to gain access to the sensitive stored data. Recently, anew kind of attacks called combined attacks has appeared. They aim to induceperturbations in the application’s execution environment. Thus, correct andlegitimate application can be dynamically modified to become a hostile one af-ter being loaded in the card using a fault injection. In this paper, we treat theproblem from another angle: how to design an innocent looking code in sucha way that it becomes intentionally hostile after being activated by a fault in-jection? We present an original approach of backward code construction basedon constraints satisfaction and a tree traversal algorithm. After that, we pro-pose a way to optimize the search process by introducing heuristics for a fasterconvergence towards more realistic solutions.We implement this approach inaTrace Generatortool; thereafter evaluate its capacity to generate the re-quired solutions while giving a proof-of-concept of the code desynchronizationtechniqueItem A formal verification of dynamic updating in a Java-based embedded system(Inderscience, 2017) Lounas, Razika; Mezghiche, Mohamed; Lanet, Jean-LouisDynamic software updating (DSU) consists in updating running programs on the fly without any downtime. This feature is interesting in critical applications that must run continuously. Because updates may lead to safety errors and security breaches, the question of their correctness is raised. Formal methods are a rigorous means to ensure the correctness required by applications using DSU. In this paper, we present a formal verification of correctness of DSU in a Java-based embedded system. Our approach is based on three major contributions. First, a formal interpretation of the semantic of update operations to ensure type safety of the update. Secondly, we rely on a functional representation of bytecode, the predicate transformation calculus and a functional model of the update mechanism to ensure the behavioural correctness of the updated programs. It is based on the use of Hoare predicate transformation to derive a specification of an updated bytecode. Thirdly, we use the functional representation to model the safe update point detectionItem A generic Multi-Agent framework for Medical-Image segmentation(2017) Bennai, Mohamed Tahar; Guessoum, Zahia; Mazouzi, Smaine; Cormier, Stéphane; Mezghiche, MohamedItem Reverse engineering Java Card and vulnerability exploitation : a shortcut to ROM(Springer, 2017) Mesbah, Abdelhak; Lanet, Jean-Louis; Mezghiche, MohamedItem Machine learning techniques to predict sensitive patterns to fault attack in the Java Card application(Taylor & Francis, 2017) Yahaoui, Chehrazed; Lanet, Jean-Louis; Mezghiche, Mohamed; Tamine, Karim