Gervais Mendy

WebRTC platform proposition as a support to the educational system of universities in a limited Internet connection context

This paper proposes a collaborative system based on WebRTC technology to improve digital universities e-Learning environment. It allows teachers and students, through a web browser, to communicate via chat, audio and camera. It also supports file transfer and screen sharing for computer connected lab equipment. All these features are functional in an IP environment without need for Internet access. For its design and realization, we had to implement a WebRTC signalisation server to manage real-time applications, using the three WebRTC APIs: MediaStream for the acquisition and synchronization of audio and video, Peer Connection for communication between users browsers and RTCDataChannel for file transfer, Chat and Screen Sharing.

Spanning graph for maximizing the influence spread in Social Networks

In this paper, we consider the influence maximization problem in social networks. The aim is to find a subset of k - nodes called seeds, which maximizes the influence spread. We propose a new approach based on the Independent Cascade Model (ICM) which extracts an acyclic spanning graph from the social network. The extraction method used to build the acyclic spanning graph is based on the existing centrality measures to determine the firsts nodes. We implement two extraction algorithms: SCG-algorithm for a connected graph and SDG-algorithm for a digraph. Both proposed algorithms are effective and their complexity is O(nm). So we use the same centrality measures to determine the seeds in the extracted graph. To show the pertinence of our approach, the results showed that the seeds given by the acyclic spanning graph give better results than the seeds given by the initial graph. This seeds will be determined by using the same heuristic like degree heuristic, degree discount heuristic, degree diffusion heuristic. The performances of this approach are very perceptible through the simulation carried out by the R software and the igraph package.

Predictive Assessment of Response Time for Road Traffic Video Surveillance Systems: The Case of Centralized and Distributed Systems

In this paper, we propose mathematical models for predictive assessment of response times of road traffic video surveillance systems. Their performances depend highly on the ability to perceive mobiles within a certain radius of networked sensors, then distinguish their potential trajectory for further decision making. Most QoS measurements and evaluations used within actual literature are hardware based, and do not consider the influence of the technical architecture. We therefore proposed a process based decomposition of video surveillance systems to obtain functions approximating each ones time consumption. The integration of these components guided us to generic mathematical models validated through experimentations. The comparison between them shows a considerably lower response time for a distributed architecture over a centralized.

A quantification model of internal control impact on banking risks using FMECA

In this paper, we propose an optimal assessment of internal control impact on banking risks by making automatic the residual risk estimation step of FMECA which is based on an inductive reasoning to study causes, effects of failures and their criticality. For this we defined three equations based on maturity and type of controls then we have obtain a mathematical model which is applied on 333 risks and 491 controls. This model is a new approach which reduce time for obtaining residuals risks likelihood and severity and decrease estimation error rate of residual criticality by harmonizing the evaluation method. Test results are satisfactory for all banking processes and types of risk.

Proper Hamiltonian Paths in Edge-Colored Multigraphs

Abstract A c -edge-colored multigraph has each edge colored with one of the c available colors and no two parallel edges have the same color. A proper hamiltonian path is a path containing all the vertices of the multigraph such that no two adjacent edges have the same color. In this work we establish sufficient conditions for a multigraph to have a proper hamiltonian path, depending on several parameters such as the number of edges, the rainbow degree, etc.

Modeling the Effect of Security Measures on Electronic Payment Risks

Nowadays Banking is very digitized but electronic payment products are vulnerable to different types of attacks. Banks implement many security measures to manage fraud related to the use of debit, credit or prepaid cards. Also, they assess the impact of implemented security measures using a manual method which has some limits including many work sessions, significant level of expertise and estimation error. In this paper, we propose to quantify the impact of security measures on electronic payment risks by defining a mathematical model which is based on FMECA. For testing, the values obtained with the model were compared to reference values given by assessors during different working sessions and the correlation rate is satisfactory. The findings of the study help to assess maturity of implemented security measures and improve security of electronic payment transactions.

Centralized and Distributed Architectures: Approximation of the Response Time in a Video Surveillance System of Road Traffic by Logarithm, Power and Linear Functions

In this article, we propose mathematical models that result in logarithmic, power and linear functions for the predictive evaluation of the response times of video surveillance systems in smart cities. Most of the QoS measurements and evaluations used in the current literature are hardware based and do not take into account the influence of the technical architecture. We have therefore proposed a decomposition process of video surveillance systems to obtain mathematical approximations of each treatment time. The integration of these components guided us towards generic mathematical models validated by experimentation. The measurements resulting from the experiment were approached with logarithmic, power and linear functions before adopting the most precise model between distributed and centralized architectures. The comparison between these architectures shows a much lower response time for the distributed architecture especially with the determination coefficient \(R^2\) of the functions.

An Approach to Maximize the Influence Spread in the Social Networks

In this paper, we treat the influence maximization problem in social networks. In this work, we attach importance to the initial diffusers called the seeds. The main goal is to find in a given social network an effective subset of kusers which begin the influence maximization. Our approach is to prevent information feedback to seeds while their selection. This prevention is to extract a specific spanning graph before the determination of seeds. At first, we propose two algorithms called SCG v1-algorithm and SCG v2-algorithm. The first algorithm randomly builds the children of the nodes while the second uses the neighborhood for the construction of the children nodes. These two versions take as input data a connected graph. So, we propose a generalization of both versions called SG-algorithm which takes as input data an arbitrary graph. These algorithms are effective and have each one a polynomial complexity. To show the pertinence of our approach, three seeds sets are determined and the one given by our approach gives better results. The performances of this approach are very perceptible through the simulation carried out by the R software and the igraph package.

Quantify the Maturity of Internet Banking Security Measures in WAEMU (West African Economic and Monetary Union) Banks

WAEMU banks should provide more facilities and convenience to theirs customers but they also should take all steps and expensive measures to make online transactions more safe and secure. Several type of controls are proposed to manage different risks related to infiltrations, breaching, stealing data and cyber-attacks. Controls maturity are measured using the actual method which is manual, require time and personal investment and have some estimation error. In this paper, we propose and apply two models on all internet banking controls in order to automatize the quantification of their maturity. The both models allow optimal assessment of security measures and aim to improve security of Ebanking transactions including increase of comfort and time saving for underserved areas. The results of our study also enable economic/social well-being and financial inclusion to people in rural areas who use internet connection for mobile banking transactions.

Multi-diffusion Degree Centrality Measure to Maximize the Influence Spread in the Multilayer Social Networks

In this work, we study the influence maximization in multilayer social networks. This problem is to find a set of k persons, called seeds, that maximizes the information spread in a multilayer social network. In our works, we focus in the determination of the seeds by proposing a centrality measure called Multi-Diffusion Degree (denoted by \(C_{dd}^{MLN}\)) based on Independent Cascade model. We consider the \(top-K\) persons as the most influential. This centrality measure uses firstly, the diffusion probability for each person in each layer. Secondly, it uses the contribution of the first neighbors in the diffusion process. To show the performance of our approach, we compare it with the existing heuristics like multi degree centrality. With software R and igraph package, we show that Multi-Diffusion Degree is more performant than the benchmark heuristic.