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Adsorption-desorption of phenolic compounds from olive mills wastewater using Tunisian natural clay

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Chinese Journal of Chemical Engineering 2021年第12期34卷 287-292页

作者： Islem Chaari Atef Touil mounir Medhioub Useful Materials Valorization Laboratory National Center for Research in Materials SciencesSoliman 8027Tunisia Department of Geology Faculty of ScienceSfaxTunisia

Olive mills wastewater(OMW) exhibit substantial contaminated properties due to their content of phenolic constituents and organic substances. The purpose of this work was the investigation of the efficiency of clay materials for the adsorption of phenolic compounds, which are contained in ***, thermal activation of the clay took place in order to improve phenolic compounds uptake and afterwards, desorption process was studied. The adsorbent was characterized using XRD, XRF and BET surface area analyses. The adsorption efficiency of phenolic compounds by raw and calcined clay at 600 °C was 77.61% and 84.21%, respectively at acidic p H. The values of Gibbs free energy indicated that adsorption process is spontaneous and beneficial at higher temperatures. Alkaline medium was propitious for phenolic compounds desorption. The obtained results showed that natural clay could be used as a low-cost adsorbent for OMW treatment.

关键词： Clayey material Adsorption Phenolic compounds Olive mills wastewaters Desorption

Reconstructing urban wind flows for urban air mobility using reduced-order data assimilation

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Theoretical & Applied Mechanics Letters 2023年第4期13卷 291-298页

作者： mounir Chrit Department of Atmospheric Sciences University of North DakotaGrand Forks 58202-9006United States

Advancements in uncrewed aircrafts and communications technologies have led to a wave of interest and investment in unmanned aircraft systems(UASs)and urban air mobility(UAM)vehicles over the past *** support this emerging aviation application,concepts for UAS/UAM traffic management(UTM)systems have been *** characterizing and predicting the microscale weather conditions,winds in particular,will be critical to safe and efficient operations of the small UASs/UAM aircrafts within the *** study implements a reduced order data assimilation approach to reduce discrepancies between the predicted urban wind speed with computational fluid dynamics(CFD)Reynolds-averaged Navier Stokes(RANS)model with real-world,limited and sparse *** developed data assimilation system is *** observations are simulated using a large eddy simulation(LES).The data assimilation approach is based on the time-independent variational framework and uses space reduction to reduce the memory cost of the *** approach leads to error reduction throughout the simulated domain and the reconstructed field is different than the initial guess by ingesting wind speeds at sensor locations and hence taking into account flow unsteadiness in a time when only the mean flow quantities are *** locations where wind sensors can be installed are discussed in terms of their impact on the resulting wind *** is shown that near-wall locations,near turbulence generation areas with high wind speeds have the highest *** the model error with its principal mode provides a better agreement with the truth and the hazardous areas for UAS navigation increases by more than 10%as wind hazards resulting from buildings wakes are better simulated through this process.

关键词： Urban Air Mobility Data Assimilation Computational Fluid Dynamics Principal Component Analysis Model Reduction Variational Data Assimilation

On the sub-mixed fractional Brownian motion

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Applied Mathematics(A Journal of Chinese Universities) 2015年第1期30卷 27-43页

作者： El-Nouty Charles Zili mounir Universite Paris XIII Department of Mathematics Faculty of Sciences of Monastir

Let {S t H, t ≥ 0） be a linear combination of a Brownian motion and an independent sub-fractional Brownian motion with Hurst index 0 〈 H 〈 1. Its main properties are studied. They suggest that SH lies between the sub-fractional Brownian motion and the mixed fractional Brownian motion. We also determine the values of H for which SH is not a semi-martingale.

关键词： mixed Gaussian processes sub-fractional Brownian motion no stationary increments semi-martingales convexity.

Determination and Analysis of Optical Constant of Annealed Sn_2Sb_2S_5 Thin Films

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Acta Metallurgica Sinica(English Letters) 2015年第5期28卷 656-662页

作者： Yousra Fadhli Adel Rabhi mounir Kanzari Laboratoire de Photovoltaque et Matriaux Semi-Conducteurs ENIT BP 37 Le belvdère 1002 Tunis Tunisia

The effects of annealing on structural, optical and electrical properties of Sn2Sb2S5 thin films were studied. Sn2Sb2S5 thin films were deposited on no-heated glass substrates by single source vacuum evaporation method. The as- deposited films were annealed in air for 1 h at 100, 200 and 300 ℃. XRD study shows that annealed films are crystallized according to the preferential orientation （602）. Optical measurements show that the thin films have relatively high absorption coefficients in the range of 10s-106 cm-1 in the energy range of 2-3.25 eV. It is also found that Sn2Sb2S5 exhibit two optical direct transitions. The models of Wemple-DiDomenico and Spitzer-Fan were applied for the analysis of the dispersion of the refractive index and the determination of the optical and dielectric constants. The electrical resistivity measurements are recorded, and two activation energy values are determined. The layers annealed at 200 and 300 ℃ exhibit a resistive hysteresis behavior. The properties reported here offer perspective to Sn2SbES5 for its application in many advanced technologies.

关键词： Sn2Sb2S5 thin films Optical constants Electrical properties

One-dimensional heat equation with discontinuous conductance

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Science China Mathematics 2015年第1期58卷 97-108页

作者： CHEN Zhen-Qing ZILI mounir Department of Mathematics University of Washington Department of Mathematics Faculty of Sciences of MonastirAvenue de l'environnement

We study a second-order parabolic equation with divergence form elliptic operator,having a piecewise constant diffusion coefficient with two points of *** partial differential equations appear in the modelization of diffusion phenomena in medium consisting of three kinds of *** probabilistic methods,we present an explicit expression of the fundamental solution under certain *** also derive small-time asymptotic expansion of the PDE’s solutions in the general *** obtained results are directly usable in applications.

关键词： stochastic differential equation semimartingale local time strong solution skew Brownian mo-tion heat kernel asymptotic expansion

Moments and Pasek's methods for parameter identification of a DC motor

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Journal of Zhejiang University-Science C(Computers and Electronics) 2011年第2期12卷 124-131页

作者： mounir HADEF Mohamed-Rachid MEKIDECHE Université de Jijel Laboratoire LAMEL B.P. 98 Ouled Aissa 18000 Jijel Algérie

Time moments have been introduced in automatic control because of the analogy between the impulse response of a linear system and a probability function. Pasek described a testing procedure for determining the DC parameters from the current response to a step in the armature voltage motor. In this paper, two identification algorithms developed based on the moments and Pasek's methods are introduced and applied to the parameter identification of a DC motor. The simulation and experimental results are presented and compared, showing that the moments method makes the model closer to reality, especially in a transient regime.

关键词： Identification Moments method Pasek’s identification method Separately excited DC motor

Multi-sensor Data Fusion for Wheelchair Position Estimation with Unscented Kalman Filter

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International Journal of Automation and computing 2018年第2期15卷 207-217页

作者： Derradji Nada mounir Bousbia-Salah Maamar Bettayeb LASA laboratory Department of Electronics Faculty of Engineering Badji Mokhtar Annaba University Department of Electrical and Computer Engineering College of Engineering University of Sharjah

This paper investigates the problem of estimation of the wheelchair position in indoor environments with noisy mea- surements. The measuring system is based on two odometers placed on the axis of the wheels combined with a magnetic compass to determine the position and orientation. Determination of displacements is implemented by an accelerometer. Data coming from sensors are combined and used as inputs to unscented Kalman filter （UKF）. Two data fusion architectures： measurement fusion （MF） and state vector fusion （SVF） are proposed to merge the available measurements. Comparative studies of these two architectures show that the MF architecture provides states estimation with relatively less uncertainty compared to SVF. However, odometers measurements determine the position with relatively high uncertainty followed by the accelerometer measurements. Therefore, fusion in the navigation system is needed. The obtained simulation results show the effectiveness of proposed architectures.

关键词： Data fusion unscented Kalman filter (UKF) measurement fusion (MF) navigation state vector fusion (SVF) wheelchair.

Lightweight Direct Acyclic Graph Blockchain for Enhancing Resource-Constrained IoT Environment

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Computers, Materials & Continua 2022年第6期71卷 5271-5291页

作者： Salaheddine Kably mounir Arioua Nabih Alaoui Laboratory of Information and Communication Technologies National School of Applied Abdelmalek Saadi UniversityTangerMorocco Ecole Supe′rieure d’informatique et du Nume′rique TICLab Universite′Internationale de Rabat SalaEl JadidaMorocco

Blockchain technology is regarded as the emergent security solution for many applications related to the Internet of Things(IoT).In concept,blockchain has a linear structure that grows with the number of transactions *** growth in size is the main obstacle to the blockchain,which makes it unsuitable for resource-constrained IoT ***,conventional consensus algorithms such as PoW,PoS are very computationally *** paper solves these problems by introducing a new lightweight blockchain structure and lightweight consensus *** Multi-Zone Direct Acyclic Graph(DAG)Blockchain(Multizone-DAG-Blockchain)framework is proposed for the fog-based IoT *** this context,fog computing technology is integrated with the IoT to offload IoT tasks to the fog nodes,thus preserving the energy consumption of the IoT *** IoT and fog nodes are initially authenticated using a non-cloneable physical function-based validationmechanism(DPUF-VM)inwhichmultiple authentication certificates are verified in the *** transaction is stored in a hash function in the blockchain using the lightweight CubeHash algorithm and signed by the Four-Q-Curve *** the cloud,sensitive data is stored as *** nodes provide data security to avoid the energy consumption and complexity of IoT *** fog node first performs a redundancy analysis using the Jaccard Similarity(JS)measure and sensitivity analysis using the Neutrosophic Neural Intelligent Network(N2IN)algorithm.A lightweight proof-of-authentication(PoAh)algorithm is presented and executed by the optimal consensus node selected by the bi-objective spiral optimization(BoSo)algorithm for transaction *** proposed work is modeled in Network Simulator 3.26(ns-3.26),and the performance is evaluated in terms of energy consumption,storage cost,response time,and throughput.

关键词： Multi zone DAG blockchain dynamic PUF lightweight PoAh consensus BoSo node selection four-q-curve encryption IoT environment

Survey on Segmentation and Classification Techniques of Satellite Images by Deep Learning Algorithm

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Computers, Materials & Continua 2023年第6期75卷 4973-4984页

作者： Atheer Joudah Souheyl Mallat mounir Zrigui Department of Computer Sciences University of MonastirMonastir1001Tunisia Research Laboratory in Algebra Numbers Theory and Intelligent SystemsMonastir1001Tunisia

This survey paper aims to show methods to analyze and classify field satellite images using deep learning and machine learning *** of deep learning-based Convolutional Neural Network(CNN)technology to harvest fields from satellite images or generate zones of interest were among the planned application scenarios(ROI).Using machine learning,the satellite image is placed on the input image,segmented,and then *** contem-porary categorization,field size ratio,Local Binary Pattern(LBP)histograms,and color data are taken into *** satellite image localization has several practical applications,including pest management,scene analysis,and field *** relationship between satellite images in a specific area,or contextual information,is essential to comprehending the field in its whole.

关键词： Identification satellite images classify deep learning machine learning