Contribution à la modélisation des applications temps réel d'aide à la conduite

Advanced Driver Assistance Systems (ADAS) manage an important volume of data that must be updated regularly. However, ADAS don't store, nor manage efficiently these data. For these reasons, we propose to integrate a real-time (RT) database system into ADAS. The integration of the RT database system allows improving the fault tolerance, reducing the number of transactions and minimizing their response time. The management of a lot of data makes these systems complex, thus, their design is highly difficult. To tackle this problem, we have proposed three patterns based on the pattern development process. This process allows defining the steps to follow in order to determine the functionalities and the requirements of the driver assistance domain on one hand, and defining the unification rules for the generation of the UML class and sequence diagrams, on the other hand. In order to represent these patterns, we have proposed UML-RTDB2 profile, which allows (i) expressing the variability of patterns, (ii) representing the real time constraints and the non functional properties and (iii) identifying the role played by each pattern element in a pattern instance. Once the proposed patterns are created, they can be reused by designers to model a specific application. For this reason, we have proposed a process to assist the applications designers when instantiating the patterns solutions. Finally, we have evaluated these patterns based on two categories of metrics.Les systèmes d'aide à la conduite gèrent un grand volume de données qui doivent être mises à jour régulièrement. Cependant, ces systèmes ne permettent, ni de les stocker, ni de les gérer d'une manière efficace. Pour ces raisons, nous proposons l'intégration d'un système de bases de données temps réel (TR) dans les systèmes d'aide à la conduite. Cela permet d'améliorer la tolérance aux fautes, de réduire le nombre de transactions et de réduire leur temps de réponse. La gestion d'un grand volume de données et leurs contraintes TR rend ces systèmes plus complexes, ce qui rend leur modélisation plus difficile. Pour remédier à cette complexité, nous avons proposé trois patrons de conception en nous basant sur un processus de création de patrons. Ce processus permet de définir les étapes à suivre pour déterminer les fonctionnalités et les exigences du domaine d'aide à la conduite, d'une part, et de définir les règles d'unification pour générer les diagrammes UML de classes et de séquence, d'autre part. Pour représenter ces patrons, nous avons proposé le profil UML-RTDB2, pour tenir compte : (i) de l'expression de la variabilité des patrons, (ii) de la représentation des contraintes TR et des aspects non fonctionnels et (iii) des éléments instanciés à partir des patrons lors de la modélisation d'une application cible. Une fois les patrons créés, ils peuvent être réutilisés par les concepteurs pour modéliser des systèmes spécifiques. Pour cela, nous avons proposé un processus de réutilisation pour guider les concepteurs d'applications lors de la réutilisation des solutions de patrons. Enfin, nous avons procédé à l'évaluation de ces patrons en utilisant deux catégories de métriques

The evolving SARS-CoV-2 epidemic in Africa: Insights from rapidly expanding genomic surveillance

INTRODUCTION Investment in Africa over the past year with regard to severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) sequencing has led to a massive increase in the number of sequences, which, to date, exceeds 100,000 sequences generated to track the pandemic on the continent. These sequences have profoundly affected how public health officials in Africa have navigated the COVID-19 pandemic. RATIONALE We demonstrate how the first 100,000 SARS-CoV-2 sequences from Africa have helped monitor the epidemic on the continent, how genomic surveillance expanded over the course of the pandemic, and how we adapted our sequencing methods to deal with an evolving virus. Finally, we also examine how viral lineages have spread across the continent in a phylogeographic framework to gain insights into the underlying temporal and spatial transmission dynamics for several variants of concern (VOCs). RESULTS Our results indicate that the number of countries in Africa that can sequence the virus within their own borders is growing and that this is coupled with a shorter turnaround time from the time of sampling to sequence submission. Ongoing evolution necessitated the continual updating of primer sets, and, as a result, eight primer sets were designed in tandem with viral evolution and used to ensure effective sequencing of the virus. The pandemic unfolded through multiple waves of infection that were each driven by distinct genetic lineages, with B.1-like ancestral strains associated with the first pandemic wave of infections in 2020. Successive waves on the continent were fueled by different VOCs, with Alpha and Beta cocirculating in distinct spatial patterns during the second wave and Delta and Omicron affecting the whole continent during the third and fourth waves, respectively. Phylogeographic reconstruction points toward distinct differences in viral importation and exportation patterns associated with the Alpha, Beta, Delta, and Omicron variants and subvariants, when considering both Africa versus the rest of the world and viral dissemination within the continent. Our epidemiological and phylogenetic inferences therefore underscore the heterogeneous nature of the pandemic on the continent and highlight key insights and challenges, for instance, recognizing the limitations of low testing proportions. We also highlight the early warning capacity that genomic surveillance in Africa has had for the rest of the world with the detection of new lineages and variants, the most recent being the characterization of various Omicron subvariants. CONCLUSION Sustained investment for diagnostics and genomic surveillance in Africa is needed as the virus continues to evolve. This is important not only to help combat SARS-CoV-2 on the continent but also because it can be used as a platform to help address the many emerging and reemerging infectious disease threats in Africa. In particular, capacity building for local sequencing within countries or within the continent should be prioritized because this is generally associated with shorter turnaround times, providing the most benefit to local public health authorities tasked with pandemic response and mitigation and allowing for the fastest reaction to localized outbreaks. These investments are crucial for pandemic preparedness and response and will serve the health of the continent well into the 21st century

Contribution to the modelling of real time advanced assistance systems

Les systèmes d'aide à la conduite gèrent un grand volume de données qui doivent être mises à jour régulièrement. Cependant, ces systèmes ne permettent, ni de les stocker, ni de les gérer d'une manière efficace. Pour ces raisons, nous proposons l'intégration d'un système de bases de données temps réel (TR) dans les systèmes d'aide à la conduite. Cela permet d'améliorer la tolérance aux fautes, de réduire le nombre de transactions et de réduire leur temps de réponse. La gestion d'un grand volume de données et leurs contraintes TR rend ces systèmes plus complexes, ce qui rend leur modélisation plus difficile. Pour remédier à cette complexité, nous avons proposé trois patrons de conception en nous basant sur un processus de création de patrons. Ce processus permet de définir les étapes à suivre pour déterminer les fonctionnalités et les exigences du domaine d'aide à la conduite, d'une part, et de définir les règles d'unification pour générer les diagrammes UML de classes et de séquence, d'autre part. Pour représenter ces patrons, nous avons proposé le profil UML-RTDB2, pour tenir compte : (i) de l'expression de la variabilité des patrons, (ii) de la représentation des contraintes TR et des aspects non fonctionnels et (iii) des éléments instanciés à partir des patrons lors de la modélisation d'une application cible. Une fois les patrons créés, ils peuvent être réutilisés par les concepteurs pour modéliser des systèmes spécifiques. Pour cela, nous avons proposé un processus de réutilisation pour guider les concepteurs d'applications lors de la réutilisation des solutions de patrons. Enfin, nous avons procédé à l'évaluation de ces patrons en utilisant deux catégories de métriques.Advanced Driver Assistance Systems (ADAS) manage an important volume of data that must be updated regularly. However, ADAS don't store, nor manage efficiently these data. For these reasons, we propose to integrate a real-time (RT) database system into ADAS. The integration of the RT database system allows improving the fault tolerance, reducing the number of transactions and minimizing their response time. The management of a lot of data makes these systems complex, thus, their design is highly difficult. To tackle this problem, we have proposed three patterns based on the pattern development process. This process allows defining the steps to follow in order to determine the functionalities and the requirements of the driver assistance domain on one hand, and defining the unification rules for the generation of the UML class and sequence diagrams, on the other hand. In order to represent these patterns, we have proposed UML-RTDB2 profile, which allows (i) expressing the variability of patterns, (ii) representing the real time constraints and the non functional properties and (iii) identifying the role played by each pattern element in a pattern instance. Once the proposed patterns are created, they can be reused by designers to model a specific application. For this reason, we have proposed a process to assist the applications designers when instantiating the patterns solutions. Finally, we have evaluated these patterns based on two categories of metrics

Definition of Design Patterns for Advanced Driver Assistance Systems

International audienc

A Real-Time Design Pattern for Actuators in Advanced Driver Assistance Systems

International audienc

Defining a UML profile for the consistency of design patterns

International audienc

An UML profile for representing real-time design patterns

International audienc

Definition and Reuse of Analysis Patterns for Real-Time Applications

International audienc

A Real-Time Design Pattern for Actuators in Advanced Driver Assistance Systems

International audienc

Metrics for Measuring Quality of Real-time Design Patterns

International audienc