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Discrete spread model for COVID-19: the case of Lebanon

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Quantitative Biology 2022年第2期10卷 157-171页

作者： ayman mourad Fatima Mroue Department of Mathematics Faculty of SciencesLebanese UniversityHadat 1500Lebanon Department of Mathematics American University of BeirutBeirut 11072020Lebanon

Background: Mathematical models are essential to predict the likely outcome of an epidemic. Various models have been proposed in the literature for disease spreads. Some are individual based models and others are compartmental models. In this study, discrete mathematical models are developed for the spread of the coronavirus disease 2019 (COVID-19).Methods: The proposed models take into account the known special characteristics of this disease such as the latency and incubation periods, and the different social and infectiousness conditions of infected people. In particular, they include a novel approach that considers the social structure, the fraction of detected cases over the real total infected cases, the influx of undetected infected people from outside the borders, as well as contact-tracing and quarantine period for travelers. The first model is a simplified model and the second is a complete ***: From a numerical point of view, the particular case of Lebanon has been studied and its reported data have been used to estimate the complete discrete model parameters using optimization techniques. Moreover, a parameter analysis and several prediction scenarios are presented in order to better understand the role of the ***: Understanding the role of the parameters involved in the models help policy makers in deciding the appropriate mitigation measures. Also, the proposed approach paves the way for models that take into account societal factors and complex human behavior without an extensive process of data collection.

关键词： discrete stochastic modeling COVID-19 numerical simulation

Energy Decay for the Elastic Wave Equation with A Local Time-dependent Nonlinear Damping

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Acta Mathematica Sinica,English Series 2008年第7期24卷 1175-1192页

作者： mourad BELLASSOUED Faculty of Sciences of Bizerte Department of Mathematics7021 Jarzouna BizerteTunisia

In this paper, we shall investigate the decay property of the solutions to the initial-boundary value problem for the elastic wave equation with a local time-dependent nonlinear damping. We give some decay rate of the energy when the damping term is effective only in a neighborhood of a suitable subset of the boundary. The results obtained in this paper extend, in particular, the known results for the scalar wave equation.

关键词： stabilization energy decay rate elasticity system

Hybrid immunizing solution for job recommender system

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Frontiers of Computer Science 2017年第3期11卷 511-527页

作者： Shaha AL-OTAIBI mourad YKHLEF Department of Information Systems College of Computer and Information Sciences Princess Nourah Bint Abdulrahman University Riyadh 11671 Saudi Arabia Department of Information Systems College of Computer and Information Sciences King Saud University Riyadh 11543 Saudi Arabia

Two traditional recommendation techniques, content-based and collaborative filtering （CF）, have been widely used in a broad range of domain areas. Both meth- ods have their advantages and disadvantages, and some of the defects can be resolved by integrating both techniques in a hybrid model to improve the quality of the recommendation. In this article, we will present a problem-oriented approach to design a hybrid immunizing solution for job recommen- dation problem from applicant＇s perspective. The proposed approach aims to recommend the best chances of opening jobs to the applicant who searches for job. It combines the artificial immune system （AIS）, which has a powerful explo- ration capability in polynomial time, with the collaborative filtering, which can exploit the neighbors＇ interests. We will discuss the design issues, as well as the hybridization process that should be applied to the problem. Finally, experimental studies are conducted and the results show the importance of our approach for solving the job recommendation problem.

关键词： content-based collaborative filtering (CF) hy- bridization computational intelligence (CI) artificial im- mune system (AIS) clonal selection correlation-based simi- larity

Analytical fits to the synchrotron functions

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Research in Astronomy and Astrophysics 2013年第6期13卷 680-686页

作者： mourad Fouka Saad Ouichaoui Research Center in Astronomy Astrophysics and GeophysicsB. P. 63 Algiers ObservatoryBouzaréah Algiers Algeria Université des Sciences et de la Technologie Houari Boumediène (USTHB) Faculté dePhysique Laboratoire SNIRMB.P. 32 El-Alia 16111 Bab Ezzouar Algiers Algeria

Accurate fitting formulae to the synchrotron function, F（x）, and its com- plementary function, G（x）, are performed and presented. The corresponding relative errors are less than 0.26% and 0.035% for F（x） and G（x）, respectively. To this end we have, first, fitted the modified Bessel functions, Ks/3（x） and K2/3（x）. For all the fitted functions, the general fit expression is the same, and is based on the well known asymptotic forms for low and large values of z for each function. It consists of multi- plying each asymptotic form by a function that tends to unity or zero for low and large values of z. Simple formulae are suggested in this paper, depending on adjustable parameters. The latter have been determined by adopting the Levenberg-Marquardt algorithm. The proposed formulae should be of great utility and simplicity for com- puting spectral powers and the degree of polarization for synchrotron radiation, both for laboratory and astrophysical applications.

关键词： radiation processes: non thermal -- methods: analytical

Parametric Estimation of Interconnected Nonlinear Systems Described by Input-output Mathematical Models

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International Journal of Automation and computing 2016年第4期13卷 364-381页

作者： mourad Elloumi Samira Kamoun Laboratory of Sciences and Techniques of Automatic Control & Computer Engineering National Engineering School of Sfax (ENIS) University of Sfax Tunisia B.P. 1173 3038 Sfax Tunisia

In this paper, two types of mathematical models are developed to describe the dynamics of large-scale nonlinear systems, which are composed of several interconnected nonlinear subsystems. Each subsystem can be described by an input-output nonlinear discrete-time mathematical model, with unknown, but constant or slowly time-varying parameters. Then, two recursive estimation methods are used to solve the parametric estimation problem for the considered class of the interconnected nonlinear systems. These methods are based on the recursive least squares techniques and the prediction error method. Convergence analysis is provided using the hyper-stability and positivity method and the differential equation approach. A numerical simulation example of the parametric estimation of a stochastic interconnected nonlinear hydraulic system is treated.

关键词： Large-scale nonlinear systems interconnected nonlinear systems deterministic systems stochastic systems input-outputmathematical models parametric estimation algorithm convergence analysis.

Additive Preservers of Drazin Invertible Operators with Bounded Index

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Acta Mathematica Sinica,English Series 2017年第9期33卷 1225-1241页

作者： mourad OUDGHIRI Khalid SOUILAH Departement Math-Info Labo LAGAFaculte des SciencesUniversite Mohammed Premier60000 OujdaMaroc

Let B（X） be the algebra of all bounded linear operators on an infinite-dimensional complex or real Banach space X. Given an integer n 〉 1, we show that an additive surjective map Ф on B（X） preserves Drazin invertible operators of index non-greater than n in both directions if and only if Ф is either of the form Ф（T） = aATA-1 or of the form Ф（T） = aBT＊B-1 where a is a non-zero scalar, A ： X → X and B ： X＊ → X are two bounded invertible linear or conjugate linear operators.

关键词： Linear preserver problems Drazin inverse ascent descent

A comprehensive simulator for assessing the reliability of a photovoltaic panel peak power tracking system

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Frontiers in Energy 2015年第2期9卷 170-179页

作者： Nabil KAHOUL mourad HOUABES Ammar NECAIBIA Laboratoire d' Electrotechnique d' Annaba Badji Mokhtar-AnnabaUniversity Annaba 23000 Algeria Research Unit of Renewable Energy in Saharan Middle (URER/MS) Adrar 01000 Algeria

When designing a maximum power point tracking （MPPT） algorithm, it is often difficult to correctly predict, before field testing, the behavior of this MPPT under varying solar irradiation on photovoltaic （PV） panels. A solution to this problem is to design a maximum power point trackers simulator of a PV system used to test MPPT algorithms. This simulator must have the same role as the MPPT card of the PV panel and thus will fully emulate the response of a real MPPT card of the PV panel. Therefore, it is a good substitute to help to test the peak power trackers of the PV system in the laboratory. This paper describes a simple peak power trackers simulator of the PV system which has a short response time thus, can be used to test MPPT algorithms under very rapid variation condition. The obtained results and the theoretical operation confirm the reliability and the superior perfor- mance of the proposed model.

关键词： photovoltaicdesign maximum powermicroprocessormodule DC-DC converter,point tracking (MPPT) card,

A Review of Generative Adversarial Networks for Intrusion Detection Systems: Advances, Challenges, and Future Directions

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Computers, Materials & Continua 2024年第11期81卷 2053-2076页

作者： Monirah Al-Ajlan mourad Ykhlef Information Systems Department King Saud UniversityRiyadh11495Saudi Arabia

The ever-growing network traffic threat landscape necessitates adopting accurate and robust intrusion detection systems(IDSs).IDSs have become a research hotspot and have seen remarkable performance *** adversarial networks(GANs)have also garnered increasing research interest recently due to their remarkable ability to generate *** paper investigates the application of(GANs)in(IDS)and explores their current use within this research *** delve into the adoption of GANs within signature-based,anomaly-based,and hybrid IDSs,focusing on their objectives,methodologies,and ***,GANs have been widely employed,mainly focused on solving the class imbalance issue by generating realistic attack *** GANs have shown significant potential in addressing the class imbalance issue,there are still open opportunities and challenges to be *** attention has been paid to their applicability in distributed and decentralized domains,such as IoT *** and scalability have been mostly overlooked,and thus,future works must aim at addressing these gaps.

关键词： Intrusion detection systems network security generative networks deep learning dataset

Firefly-CDDL:A Firefly-Based Algorithm for Cyberbullying Detection Based on Deep Learning

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Computers, Materials & Continua 2023年第4期75卷 19-34页

作者： Monirah Al-Ajlan mourad Ykhlef Department of Information Systems College of Computer and Information SciencesKing Saud UniversityRiyadhKSA

There are several ethical issues that have arisen in recent years due to the ubiquity of the Internet and the popularity of social media and community *** them is cyberbullying,which is defined as any violent intentional action that is repeatedly conducted by individuals or groups using online channels against victims who are not able to react *** alarmingly high percentage of people,especially teenagers,have reported being cyberbullied in recent years.A variety of approaches have been developed to detect cyberbullying,but they require time-consuming feature extraction and selection ***,no approach to date has examined the meanings of words and the semantics involved in *** past work,we proposed an algorithm called Cyberbullying Detection Based on Deep Learning(CDDL)to bridge this *** eliminates the need for feature engineering and generates better predictions than traditional approaches for detecting *** was accomplished by incorporating deep learning—specifically,a convolutional neural network(CNN)—into the detection *** this algorithm shows remarkable improvement in performance over traditional detection mechanisms,one problem with it persists:CDDL requires that many parameters(filters,kernels,pool size,and number of neurons)be set prior to *** parameters play a major role in the quality of predictions,but a method for finding a suitable combination of their values remains *** address this issue,we propose an algorithm called firefly-CDDL that incorporates a firefly optimisation algorithm into CDDL to automate the hitherto-manual trial-and-error hyperparameter *** proposed method does not require features for its predictions and its detection of cyberbullying is fully *** firefly-CDDL outperformed prevalent methods for detecting cyberbullying in experiments and recorded an accuracy of 98%within acceptable polynomial time.

关键词： Firefly optimization convolutional neural network(CNN) cyberbullying cyberbullying detection text classification