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Identification Of An Email Author Using Machine Learning And Natural Language Processing
(2026) ELMEGUENNI Hadjar; MOHAMMED SMAIN Bouchra; BOUCHAKOUR .E
Emails are often used in cybercrime today, so it is important to verify
the identity of the email author. This paper proposes different Machine
Learning models: Naive Bayes (NB), Logistic Regression (LR) and Sup-
port Vector Machine (SVM), to solve the problem of anonymous email
author attribution. The main task is to find the author of an anonymous
email among the many suspected targets, to verify if an email was in fact
written by the sender.
In this project, the models were trained and tested using the same
email dataset where we analyze writing style, vocabulary usage, and tex-
tual patterns, plus date and time information using supervised machine
learning in addition to natural language processing techniques, with the
intention of combining multiple factors to identify the author.
The tests proved that the accuracy varies from one model to another
indicating that some are better than others. In email authorship verifica-
tion experiments, usually the average accuracy reaches 89.9%. while our
model’s accuracy rate to a well distributed dataset is 89,06% for SVM ,
81,77% for Naive Bays and 88.02% for Logistic Regression. And with a
not so well distributed dataset the accuracy rate is 91,40% for SVM model,
76,74% for Naive Bays and for Logistic Regression 92.29%. Proving that
a good identification system relies on two aspects, the model chosen for
the task and the dataset veracity.
Évaluation de la qualité bactériologique et organoleptique des Saucisses type « Merguez » commercialisées au niveau de la ville d’Ain Témouchent.
(2026) DALILE DJAOUAHIR; ATTAR FATIMA ZOHRA; AHMED AMMAR YAMINA
"Merguez" is among the meat products most exposed to microbiological alterations and risk of
contamination by microorganisms of hygienic and sanitary concern. This study mainly aims to evaluate the
bacteriological quality of merguez-type sausages commercialized in the city of Aïn Témouchent. An
organoleptic evaluation of the samples was also performed to assess their sensory characteristics and correlate
them with the bacteriological results. In total, 05 samples were collected from different retail outlets across
the city (local butcher shops). The microbiological analysis focused on the enumeration of hygiene indicator
and pathogenic microorganisms, notably Total Mesophilic Aerobic Flora (FMAT) and fecal coliforms, as well
as the detection of specific pathogens such as Staphylococcus aureus and Salmonella. In parallel, the
organoleptic evaluation was based on the criteria of color, odor, appearance, and texture. The microbiological
results reveal a worrying situation with a variable overall quality ranging between satisfactory (20%),
acceptable (40%), and unsatisfactory (40%), reflecting deficiencies during the grinding, stuffing, or cold chain
maintenance stages, or a high initial microbial load of the raw material. On the organoleptic level, most
samples exhibited an acceptable visual quality despite a high underlying microbial contamination, thereby
highlighting that organoleptic evaluation alone is insufficient to conclude on the hygienic quality of the
product. It must therefore be interpreted in conjunction with microbiological and physicochemical analyses.
This study emphasizes the imperative need to strengthen hygiene measures and intensify official controls.
Influence du degré de broyabilité du clinker sur les propriétés physico- mécaniques du ciment
(2026) Miloud Abid Ahlem; Zenasni Habiba; Serier Mohamed
Cement is a fundamental construction material whose physico-chemical and mechanical
properties directly affect structural durability. This study investigates the influence of clinker
grindability on the performance of Portland cement by analyzing the effect of fineness (45 μm
sieve residue) at different levels. A second part explores the partial substitution of clinker with
natural pozzolan up to 20%. The results demonstrate the maintenance of compliant mechanical
strength while reducing clinker content and CO2 emissions, contributing to a more sustainable and
cost-effective cement.
Existence et unicité des solutions des équations différentielles semi-linéaires d’ordre fractionnaire
(2026) KHELLADI Khedidja Samah; MEKHALFI Kheira
This dissertation studies the existence and uniqueness of mild solutions for semi-
linear fractional differential equations with finite and infinite delay in the framework
of the Riemann–Liouville fractional derivative. Banach’s Fixed Point Theorem is
used to establish uniqueness, while the Leray–Schauder nonlinear alternative pro-
vides existence results. The theory is illustrated by a tumor growth model and an
infinite-memory viscoelastic plate model.
Global Dynamics of a Nonlocal Delayed Viral Infection Model in Heterogeneous Environments
(2026) BELHADRI Mohammed Abdelmalek; BENTOUT Soufiane
This work is devoted to the mathematical analysis of within-host viral infection dynamics,
with particular emphasis on the hepatitis B virus. We first review three classical models
that progressively incorporate spatial structure: the foundational ODE model of Nowak et
al [23], the local diffusion model of Wang and Wang [29], and the nonlocal dispersal frame-
work of Wang et al [30]. We then conduct a rigorous study of the spatially heterogeneous
model proposed by Liu et al [17], which simultaneously incorporates nonlocal diffusion
of free virions governed by a probability kernel J, an intracellular delay τ > 0 reflecting
the latency between viral entry and viral production, and position-dependent biological
parameters. The analysis is carried out in an infinite-dimensional functional framework.
We establish the global well-posedness and positivity of solutions via semigroup theory
and the Banach fixed point theorem, and prove that the semiflow is bounded dissipative.
Asymptotic smoothness of the semiflow and the existence of a compact global attractor
are obtained through a Kuratowski measure argument. Finally, the global asymptotic
stability of the infection-free steady state P0 is established when R0 ≤ 1, via an explicit
Lyapunov functional whose integral kernel is the positive eigenfunction of the linearised
problem around P0.