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NuMDG:A New Tool for Multiway Decision Graphs Construction

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Journal of Computer Science & Technology 2011年第1期26卷 139-152页

作者： Sa'ed Abed Yassine Mokhtari otmane ait-mohamed Sofiene Tahar Department of Computer Engineering Hashemite UniversityZarqaJordan Department of Electrical and Computer Engineering Concordia UniversityMontrealCanada

Multiway Decision Graphs （MDGs） are a canonical representation of a subset of many-sorted first-order logic. This subset generalizes the logic of equality with abstract types and uninterpreted function symbols. The distinction between abstract and concrete sorts mirrors the hardware distinction between data path and control. Here we consider ways to improve MDGs construction. Efficiency is achieved through the use of the Generalized-If-Then-Else （GITE） commonly operator in Binary Decision Diagram packages. Consequently, we review the main algorithms used for MDGs verification techniques. In particular, Relational Product and Pruning by Subsumption are algorithms defined uniformly through this single CITE operator which will lead to a more efficient implementation. Moreover, we provide their correctness proof. This work can be viewed as a way to accommodate the ROBBD algorithms to the realm of abstract sorts and uninterpreted functions. The new tool, called NuMDG, accepts an extended SMV language, supporting abstract data sorts. Finally, we present experimental results demonstrating the efficiency of the NuMDG tool and evaluating its performance using a set of benchmarks from the SMV package.

关键词： infinite state model checking multiway decision graphs uninterpreted functions

Robust Parametric Modeling of Speech in Additive White Gaussian Noise

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Journal of Signal and Information Processing 2015年第2期6卷 99-108页

作者： Abdelaziz Trabelsi otmane ait mohamed Yves Audet Department of Electrical and Computer Engineering Concordia University Montréal Canada Department of Electrical Engineering école Polytechnique de Montréal Montréal Canada

In estimating the linear prediction coefficients for an autoregressive spectral model, the concept of using the Yule-Walker equations is often invoked. In case of additive white Gaussian noise (AWGN), a typical parameter compensation method involves using a minimal set of Yule-Walker equation evaluations and removing a noise variance estimate from the principal diagonal of the autocorrelation matrix. Due to a potential over-subtraction of the noise variance, however, this method may not retain the symmetric Toeplitz structure of the autocorrelation matrix and thereby may not guarantee a positive-definite matrix estimate. As a result, a significant decrease in estimation performance may occur. To counteract this problem, a parametric modelling of speech contaminated by AWGN, assuming that the noise variance can be estimated, is herein presented. It is shown that by combining a suitable noise variance estimator with an efficient iterative scheme, a significant improvement in modelling performance can be achieved. The noise variance is estimated from the least squares analysis of an overdetermined set of p lower-order Yule-Walker equations. Simulation results indicate that the proposed method provides better parameter estimates in comparison to the standard Least Mean Squares (LMS) technique which uses a minimal set of evaluations for determining the spectral parameters.

关键词： ARMA Model Noise Variance Overdetermined Parametric Evaluation Singular Value Representation LMS Technique Yule-Walker Equations

Capparis spinosa L waste activated carbon as an efficient adsorbent for crystal violet toxic dye removal: Modeling, optimization by experimental design, and ecological analysis

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Chinese Journal of Chemical Engineering 2024年第7期71卷 283-302页

作者： Mohammed Benjelloun Youssef Miyah Salma Ssouni Soulaiman Iaich mohamed El-habacha Salek Lagdali Khadija Saka El Mustafa Iboustaten Abdelaziz ait Addi Sanae Lairini Rabia Bouslamti Laboratory of Materials ProcessesCatalysisand EnvironmentHigher School of TechnologySidi Mohamed Ben Abdellah UniversityFez 30070Morocco Ministry of Health and Social Protection Higher Institute of Nursing Professions and Health TechniquesFez/Meknes 30070Morocco Laboratory of Biochemistry Faculty of MedicinePharmacy and DentistrySidi Mohamed Ben Abdellah UniversityFez 30070Morocco Laboratory of Applied Chemistry and Environment Faculty of SciencesIbnou Zohr UniversityAgadir 80322Morocco Research Team of Energy and Sustainable Development Higher School of TechnologyIbnou Zohr UniversityGuelmim 81000Morocco Organic Chemistry and Physical Chemistry Laboratory Faculty of SciencesIbnou Zohr UniversityAgadir 80322Morocco

Textile dyes are dramatic sources of pollution and non-aesthetic disturbance of aquatic life and therefore represent a potential risk of bioaccumulation that can affect living *** is imperative to reduce or eliminate these dyes from liquid effluents with innovative biomaterials and ***,this research aims to highlight the performance of Capparis spinosa L waste-activated carbon(CSLW-AC)adsorbent to remove crystal violet(CV)from an aqueous *** mechanism of CV adsorption on CSLW-AC was evaluated based on the coupling of experimental data and different characterization *** efficiency of the CSLW-AC material reflected by the equilibrium adsorption capacity of CV could reach more than 195.671 mg·g^(–1) when 0.5 g·L^(–1) of CSLW-AC(Particle size≤250μm)is introduced into the CV of initial concentration of 100 mg·L^(–1) at pH 6 and temperature 65℃ and in the presence of potassium ions after 60 min of contact time according to the one parameter at a time *** adsorption behavior of CV on CSLW-AC was found to be consistent with the pseudo-second-order kinetic model and Frumkin's linear isothermal *** thermodynamic aspects indicate that the process is physical,spontaneous,and *** optimization of the process by the Box Behnken design of experiments resulted in an adsorption capacity approaching 183.544 mg·g^(–1)([CV]=100 mg·L^(–1) and[CSLW-AC]=0.5 g·L^(–1) at 35 min).The results of the Lactuca sativa seeds germination in treated CV(70%),adsorbent solvent and thermal regeneration(more than 5 cycles),and process cost analysis(1.0484 USD·L^(–1))tests are encouraging and promising for future exploitations of the CSLW-AC material in different industrial fields.

关键词： Box Behnken Capparis spinosa L waste-activated carbon Cost analysis Isotherm Kinetic Regeneration

Formal proof of integer adders using all-prefix-sums operation

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Science China(Information Sciences) 2012年第9期55卷 1949-1960页

作者： mohamed otmane ait Department of Electrical and Computer Engineering Concordia UniversityMontreal H3G 1M8Canada

Addition of two binary numbers is a fundamental operation in electronic *** integer adder architectures have been *** formal properties are well known,but the proofs are either incomplete or difficult to *** this paper,we present a formal proof for the correctness of prefix *** sequential and parallel algorithms are formalized and *** contrast to previous proofs using higher order functions and rewriting systems,our work is based on first order recursive equations,which are familiar to the computer arithmetic community and are therefore understandable by people working on VLSI circuit *** study sets up a basis for further work on formal proofs of computer arithmetic algorithms.

关键词： semi-group integer adder prefix computation computer arithmetic VLSI

On the gradient tracking problem for a bilinear reaction–diffusion equation excited by distributed bounded controls

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Journal of Control and Decision 2023年第3期10卷 365-373页

作者： El Hassan Zerrik Abderrahman ait Aadi mohamed Ouhafsaa MACS Laboratory Faculty of SciencesMoulay Ismail UniversityMeknesMorocco Department of Sciences Ecole Normale SupérieureMoulay Ismail UniversityMeknesMorocco

This paper addresses a gradient tracking problem of a bilinear reaction–diffusion equation evolvingin a spatial domainΩ ⊂ Rn, n ≤ 3. Such an equation is excited with distributed and boundedcontrols. The problem is formulated by the minimisation of a functional constituted of the deviationbetween the desired gradient and the current one all over a time interval and the energyterm. Then we prove the existence of an optimal control that we characterise by an optimalitysystem. Moreover, we discuss two sets of particular controls: the set of time dependent controlsand the space dependent ones. A computational approach and illustrative simulations are alsogiven.

关键词： Infinite dimensional systems bilinear systems reaction–diffusion equation controllability optimal control

Research on Convolutional Neural Network Model for Brain Tumor Mri Classification

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Research on Convolutional Neural Network Model for Brain Tum...

作者： mohamed ait Amou 河北工业大学

学位级别：硕士

脑肿瘤是当今最具侵袭性的疾病之一,早发现、早诊断和早治疗对患者至关重要。MRI是脑肿瘤诊断中一种重要手段。随着MRI图像的大量采集和存储,面向大数据图像库,手动解释和常用解释方法是无法处理的,且检测准确率不高。因此,需要采用深... 详细信息

脑肿瘤是当今最具侵袭性的疾病之一,早发现、早诊断和早治疗对患者至关重要。MRI是脑肿瘤诊断中一种重要手段。随着MRI图像的大量采集和存储,面向大数据图像库,手动解释和常用解释方法是无法处理的,且检测准确率不高。因此,需要采用深度学习方法来进行脑肿瘤的诊断。卷积神经网络(CNN)在图像分类方面是最成功的一种深度学习方法,然而各种CNN模型繁多,针对实际数据的高维性和复杂性需要优选合适的网络模型,并对模型中的超参数进行优化。为此,本论文主要从迁移学习和贝叶斯理论出发,研究基于卷积神经网络的脑肿瘤MRI分类技术。主要研究工作如下:(1)基于VGG16的一种改进CNN模型研究。为解决VGG16模型的密集层含有大量参数、需要大量计算、占用大量内存而导致其难以在前端实现,以及在使用转移学习时如何缩放图像以适应VGG16模型的输入大小等问题,提出了一类改进的基于VGG16的CNN拓扑结构,包括四个主要改进,以获得更好的性能。其中对VGG16的原始结构做了显著改变,在3064个MRI脑肿瘤图像上建立并测试了许多模型。将最大池层的步长设置为其默认值可以显著提高整体性能。实验结果表明,VGG16-V4是四种改进的VGG16模型(VGG16-V1、VGG16-V2、VGG16-V3和VGG16-V4)中最有效的,准确率为94.93%,精确率为94.18%,召回率为94.32%,F1分数为95.02%。由于使用了随机失活(dropout),同时减少了过滤器和密集层节点的数量,因此具有优异的性能,这表明改进的VGG16拓扑结构是有效和可行的。(2)基于贝叶斯优化的CNN模型超参数优化研究。CNN模型中超参数的选择直接影响模型的准确性,为此提出了一种基于贝叶斯优化的模型,该模型采用改进的VGG16-V4体系结构,包括五个超参数(激活函数、批量大小、随机失活率、密集节点数和优化器)的最优选择。在MRI数据集上,通过将该模型与VGG16、VGG19、Res Net50、Inception V3和Dense Net201模型进行对比分析,实验结果表明,从零开始训练的CNN在脑肿瘤分类方面优于转移学习。优化后的VGG16-V4诊断准确率可达到98.70%,而基本VGG16、VGG19、Res Net50、Inception V3和Dense Net201的诊断准确率分别为97.08%、96.43%、89.29%、92.86%和94.81%。此外,该模型在CE-MRI数据集上的性能优于常用方法,表明基于贝叶斯优化的超参数优化是可行和有效的。

关键词：脑肿瘤MRI分类卷积神经网络迁移学习贝叶斯优化

Interfacial charge transfer and photocatalytic activity in a reverse designed Bi_(2)O_(3)/TiO_(2)core-shell

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Frontiers in Energy 2021年第3期15卷 732-743页

作者： Sabina ait ABDELKADER Zhenpeng CUI Abdelghani LAACHACHI Christophe COLBEAU-JUSTIN mohamed Nawfal GHAZZAL UniversitéParis-Saclay UMR 8000CNRSInstitut de Chimie PhysiqueOrsay 91405France Materials Research and Technology Department(MRT) Luxembourg Institute of Science and Technology(LIST)Käerjeng 4940Luxembourg

In this study,the electronic and photocatalytic properties of core-shell heterojunctions photocatalysts with reversible configuration of TiO_(2)and Bi_(2)O_(3)layers were *** core-shell nanostructure,obtained by efficient control of the sol-gel polymerization and impregnation method of variable precursors of semiconductors,makes it possible to study selectively the role of the interfacial charge transfer in each *** morphological,optical,and chemical composition of the core-shell nanostructures were characterized by high-resolution transmission electron microscopy,UV-visible spectroscopy and X-ray photoelectron *** results show the formation of homogenous TiO_(2)anatase and Bi_(2)O_(3)layers with a thickness of around 10 and 8 nm,*** interfacial charge carrier dynamic was tracked using time resolved microwave conductivity and transition photocurrent *** charge transfer,their density,and lifetime were found to rely on the layout layers in the core-shell *** optimal core-shell design,Bi_(2)O_(3)collects holes from TiO_(2),leaving electrons free to react and increase by 5 times the photocatalytic efficiency toward H2 *** study provides new insight into the importance of the design and elaboration of optimal heterojunction based on the photocatalyst system to improve the photocatalytic activity.

关键词： photocatalysis core-shell heterojunction H2 TiO_(2) Bi_(2)O_(3)

Copper Mineralization in the Lower Cambrian Cover of Jbel N’Zourk (Central Anti Atlas, Morocco): Tectonic-Mineralizations Relationships

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Open Journal of Geology 2023年第11期13卷 1195-1219页

作者： Achraf ait Yazza Ismail Bouskri mohamed Raji Faouziya Haissen Noura Zoraa LGAGE Faculty of Sciences Ben M’Sik Hassan II University Casablanca Morocco SOMIFER Managem Group/Al Mada Casablanca Morocco

The Moroccan Anti-Atlas is a vast geological region composed of a Precambrian basement covered by a late-Neoproterozoic to Paleozoic sedimentary sequences. More than 200 copper occurrences are listed in these sequences. The copper mineralization of the Jbel N’Zourk (Central Anti-Atlas) is observed into the lower Limestones of the lower Cambrian (Adoudou formation), just above the volcanic formations of the Jbel Boho between Bou Azzer El Graara and Zenaga inliers. The region is by an E-W shortening resulting in an overlapping structure with vergence associated with folds. Generally, the mineralization is hosted along the principal fault of Jbel N’Zourk and sometimes in the anticlines hinges. The petrographic study showed that the mineralization can be observed in several aspects, either in the fractures and veins, in small karsts or rarely disseminated in calcite and dolomite minerals. These observations host new arguments who contribute to a later reconcentration of the copper mineralization of Jbel N’Zourk, trapped on faulted and folded structures attributed to Variscan deformation.

关键词： Central Anti-Atlas Lower Cambrian Cover Copper Mineralization Structural

Versatile synthesis of cadalene and iso-cadalene from himachalene mixtures:Evidence and application of unprecedented rearrangements

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Chinese Chemical Letters 2020年第7期31卷 1851-1854页

作者： Mustapha ait El Had Abdelouahd Oukhrib mohamed Zaki Martine Urrutigoity Ahmed Benharref Remi Chauvin Laboratoire de Chimie Biomoleculaire Substances Naturelies et Reactivite(URAC 16)Faculte des Sciences SemlaliaUniversite Cadi AyyadB.P.2390MarrakechMorocco CNRS LCC(Laboratoire de Chimie de Coordination)BP 4409931077Toulouse Cedex 4France INP-ENSIACET 4 allee Emile Monso31030Toulouse CedexFrance Universite de Toulouse UPSICT-FR 259931062Toulouse Cedex 9France

From a mixture of α-,β-and y-himachalenes extracted from waste wood of Atlas cedar(Cedrus atlantica),cadalene(1,6-dimethyl-4-isopropylnaphthalene)and iso-cadalene(1,6-dimethyl-3-isopropylnaphthalene)were produced in two steps with up to 71%±5%yield through the ar-himachalene intermediate using I2 and/or AlCl3 as *** selectivity is shown to sharply depend on the operating conditions:while I2/AlCl3 in dichloromethane promotes the formation of cadalene,the formation of iso-cadalene is favored in the presence of AlCl3 in *** bicyclic aromatic compounds were thus obtained through unique rearrangements involving sequential C—C bond cleavage/fo rmation and hydride transfer *** the absence of AlCl3 or I2,dihydrocurcumene was also found to be formed with up to 70%selectivity.A tentative mechanism is proposed and discussed.

关键词： Aromatic reactivity Cadalenes Dihydrocurcumene Himachalenes Rearrangements