Browsing by Author "Lounas, Razika"

Now showing 1 - 11 of 11

Air quality monitoring using IoT : a survey
(IEEE, 2019) Mokrani, Hocine; Lounas, Razika; Bennai, Mohamed Tahar; Salhi, Dhai Eddine; Djerbi, Rachid
The increase in industrial activities and the rapidurbanization of human populations had a terrible effect onglobal air quality. Thousands of factories and billions of vehiclesrelease enormous amounts of pollutants into the air everyday; dangerously affecting human health. Many epidemiologicalstudies pointed out the responsibility of air pollution in manyhealth issues, the reason why monitoring air quality becamean obligation to prevent or limit these issues. Conventionalsystems based on measuring stations are expensive and offerlow data granularity. As a result, researchers are increasinglytargeting IOT-based systems. However, elaborating a new systemfor air quality monitoring requires an awareness of the stateof the art and the mastery of a certain amount of specificknowledge (pollutants, their health effects, the sensing equipment,the IOT possible configuration,...).This paper aims to answerthese necessities by reviewing the existing works on air qualitymonitoring using IOT with the focus on lasted trends andchallenges
An approach for formal verification of updated Java bytecode programs
(CEUR-WS, 2015) Lounas, Razika; Mezghiche, Mohamed; Lanet, J.-L.
This paper deals with formal specification and verification of Java bytecode update. Programs update for Java applications has gained a wide interest since it is used for several purposes: transforming semantics of a program, adding features to a program or performing optimizations. In this paper, we focus on program transformations for Java programs at the bytecode level. Because these transformations may introduce errors, our goal is to provide a formal way to verify the update and establish its correctness. Our approach for formal specification and verification of updated Java bytecode programs is based on four ingredients: a formal interpretation of the semantics of update operations, a functional representation of bytecode, bytecode annotation and predicate transformation calculus.We use the concept of Hoare predicate transformation to derive a specification of an annotated bytecode. Annotations are used to express update operations within the code. A functional representation is used to model annotations and bytecode. The approach derives then a new specification for the annotated bytecode using a weakest precondition calculus defined to deal with update operations. Verification conditions are then generated and proved to establish the correction of the update
A Collaborative System for Machine Learning-Based Final-Year Projects With Enhanced Dataset Accessibility
(IGI Global, 2024) Lounas, Razika; Djerbi, Rachid; Mokrani, Hocine; Bennai, Mohamed Tahar
This chapter explores the transformative impact of information and communication technology (ICT) on pedagogy, specifically focusing on the integration of collaboration tools in final year projects (FYPs). Final year projects (FYPs) represent the ultimate activity in the student's curriculum. They are designed to use, test, and enhance the knowledge students have gained over the years by confronting them with real-world projects. Despite existing systems for FYPs, the chapter identifies gaps, particularly in covering the entire FYP process and in addressing different collaborative aspects. With a focus on the rise of machine learning-based FYPs, this research aims to propose a comprehensive solution based on a proposed collaboration architecture in response to various needs such as communication, coordination, production, and resource sharing. The application is designed for multiple user roles, including students, advisors, and administrative staff, each allocated a personalized workspace. The novelty of the proposed system is its comprehensive coverage of all collaborative aspects mentioned throughout the FYP process, including proposal processing, project assignment, project completion, and evaluation. The research contributes to fostering innovation in machine learning projects by effectively managing and sharing datasets through collaboration tools. The results indicate good scores in improving collaborative aspects with a score of 98% for virtualization in coordination and 96% for communication. The results also showed that surveyed users are positively inclined to use the system as their final year project (FYP) management system, with an attention-to-use score of 90% of advisors and 92.8% of students.
Formal Methods for Internet of Things: a Concise Classification
(Université M’hamed Bougara de Boumerdes : Faculté des Sciences, 2024) Talamali, Ibtissem; Lounas, Razika; Mezghiche, Mohamed
Formal methods in dynamic software updating : a survey
(Inderscience, 2019) Lounas, Razika; Mezghiche, Mohamed; Lanet, Jean Louis
Dymanic software updating DSU consists in updating running programs on-the-fly without any downtime that leads to systems unavailability. The use of DSU in critical applications raises several issues related to update correctness. Indeed, an erroneous dynamic update may introduce safety vulnerabilities and security breaches. In this perspective, the use of formal methods has gained a large interest since they respond to the high need of rigor required by such applications. Several frameworks were developed to first express update correctness which is based on several criteria. Then, the proposed formalisms are used to specify DSU systems, express correctness criteria and establish them. In this paper, we present a review of researches on the application of formal methods to DSU systems. We give a classification of systems according to the paradigms of programming languages and then we explain the correctness criteria and categorise the articles regarding the approaches of formalisation to establish the correctness. This information is useful to help ongoing researches in having an overview on the application of formal methods in DSU
A formal verification of dynamic updating in a Java-based embedded system
(Inderscience, 2017) Lounas, Razika; Mezghiche, Mohamed; Lanet, Jean-Louis
Dynamic 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 detection
A formal verification of safe update point detection in dynamic software updating
(Springer, 2017) Lounas, Razika; Jafri, Nisrine; Legay, Axel; Mezghiche, Mohamed; Lanet, Jean-Louis
Preuve en coq de propriétés de programmes numériques partant du code en C
(2009) Lounas, Razika
L’utilisation des programmes informatiques dans des applications critiques nécessite l’utilisation des méthodes formelles basées sur la rigueur mathématique pour établir leur correction conformément à leurs spécifications. La méthode formelle Why permet de générer, à partir d’un programme C spécifié avec Caduceus, un ensemble d’obligations de preuves qu’il faut prouver à l’aide d’un assistant de preuve pour établir la correction du programme. Le calcul matriciel est intensivement utilisé dans les programmes scientifiques Ceci a engendré le développement de plusieurs librairies dont BLAS (Basic Linear Algebra Subroutines), pour permettre une écriture rapide et efficace des programmes de calcul matriciel. Dans notre travail, nous avons utilisé la méthode Why pour prouver deux programmes issus des BLAS : le produit matriciel et la résolution des systèmes. Nous avons utilisé l’assistant de preuve coq pour décharger les obligations de preuves. Pour mener les preuves, nous avons proposé une nouvelle définition du type matrice qui peut être utilisé pour prouver d’autres programmes
Towards a general framework for formal reasoning about java bytecode transformation
(2013) Lounas, Razika; Mezghiche, Mohamed; Lanet, Jean-Louis
Towards a Smart Data Transmission Strategy for IoT Monitoring Systems: Application to Air Quality Monitoring
(IEEE, 2019) Lounas, Razika; Salhi, Dhai Eddine; Mokrani, Hocine; Djerbi, Rachid
In the modern digital area, Internet of Things (IoT) is increasingly gathering attention for the implementation of applications in several aspects of everyday activities, intending to make our cities smarter and more comfortable. Therefore, the implementation of these IoT applications raises several challenges to overcome. One of these challenges is the efficient use of resources at each stage of the application, such as acquisition, storage, processing, and networking. In smart cities, many IoT monitoring systems continuously generate large amounts of data. These data volumes, before they can be processed and responded, must first be transmitted through the city's networks (Wifi, Bluetooth, LTE). To deal with this considerable amount of continually transmitted data and to reduce the load on networks, we propose an approach based on the efficient use of data compression in IoT systems. This approach uses a data compression smart strategy to reduce the transmitted data during the acquisition process and thus minimize the use of network resources while providing the user with relevant information in real-time using a prioritization mechanism. In order to show the efficiency of our proposal, we conducted experiments on a case study of an air quality monitoring system
Validation des spécifications formelles de la mise à jour dynamique des applications java card
(2018) Lounas, Razika
La mise à jour dynamique des programmes consiste en la modification de ceux-ci sans en arrêter l'exécution. Cette caractéristique est primordiale pour les applications critiques en continuelles évolutions et nécessitant une haute disponibilité. Le but de notre travail est d'effectuer la vérification formelle de la correction de la mise à jour dynamique d'applications Java Card à travers l'étude du système EmbedDSU. Pour ce faire, nous avons premièrement établi la correction de la mise à jour du code en définissant une sémantique formelle des opérations de mise à jour sur le code intermédiaire Java Card en vue d'établir la sûreté de typage des mises à jour. Nous avons ensuite proposé une approche pour vérifier la sémantique du code mis à jour à travers la définition d'une transformation de prédicats. Nous nous sommes ensuite intéressés à la vérification de la correction concernant la détection de points sûrs de la mise à jour. Nous avons utilisé la vérification de modèles. Cette vérification nous a permis de corriger d'abord un problème d'inter blocage dans le système avant d'établir d'autres propriétés de correction: la sûreté d'activation et la garantie de mise à jour. La mise à jour des données est effectuée à travers les fonctions de transfert d'état. Pour cet aspect, nous avons proposé une solution permettant d'appliquer les fonctions de transfert d'état tout en préservant la consistance du tas de la machine virtuelle Java Card et en permettant une forte expressivité dans leurs écritures