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1-Formyl-3-phenyl-5-(4-isopropylphenyl)-2-pyrazoline: Synthesis, characterization, antimicrobial activity and DFT studies
(2016-05-13) Amel Messai
The structure of 1-formyl-3-phenyl-5-(4-isopropylphenyl)-2-pyrazoline synthesized as single crystal was investigated by FTIR, NMR, XRD. Experimental data were complemented by quantum mechanical calculations. XRD data show that the compound crystallizes in the triclinic system (P 1) via trans isomer (a ¼ 6.4267(4) Å, b ¼ 10.9259(12) Å, c ¼ 12.4628(9) Å and a ¼ 102.894(8) , b ¼ 102.535(6) , g ¼ 101.633(7) ). Anti-microbial screening results indicate that the compound shows promising activity. The theoretically predicted and experimentally obtained parameters reveal further insight into pyrazoline systems
4-Methylanilinium nitrate
(2009) BOUSSEKINE
(4S)-4-Benzyl-N-{[(4S)-4-benzyl-2-oxo-1,3-oxazolidin-3yl]sulfonyl}-2-oxo-1,3-oxazolidine-3-carboxamide
(2010-06-01) Malika Berredjem
The title compound, C 21 H 21 N 3 O S, contains an oxazolidinone ring and a sulfonamide group, both characteristic for biologically and pharrmaceutically active compounds. Both stereogenic centres reveal an S absolute conﬁguration. The two oxazolidinone rings are in an envelope conformation with the methylene carbon ﬂap atoms deviating by 0.428 (1) and 0.364 (2) A 7 ˚ from the best least-square planes formed by the four other ring atoms. An intramolecular N—H O hydrogen bond contributes to the folded conformation of the molecule. In the crystal, weak intermolecular C—H O interactions connect the molecules into helices along the the twofold screw axes.
A Category-theoretic Approach to Organization-based Modeling of Multi Agent Systems on the Basis of Collective Phenomena and Organizations in Human Societies
(2016-06-30) Abderrahim Siam
This paper presents an idea of using category theory for developing organizational multi-agent systems by taking inspiration from collective phenomena and organizations in human societies. Category theory is used for studying and formalizing organizations and collective phenomena in human societies with the aim of capturing their logics into categorical models. Afterward, the captured models are mapped categorically to categorical MAS organizational models. This way of thinking allows studying properties of result MAS organizational models as well as properties of organizations in human societies such as stability and adaptation before taking them as landmarks for developing MAS organizational models.
A comparative study of two novel unsymmetrically substituted triazacyclohexanes
(2017-03-06) Amel Messai
ovel unsymmetrically N-substituted N,N0-R1N00-R2-1,3,5-triazacyclohexanes (1b and 2b; R1 ¼ p-chlorophenyl or p-methoxyphenyl and R2 ¼ butyl or cyclohexyl) have been synthesized in a good yield from condensation reaction by excess amine. Both triazacyclohexane rings have chair conformation. However, 1b adopts diaxial orientation of aryl groups and an equatorial form of alkyl group whereas 2b prefers an axial orientation of the alkyl group and diequatorial forms of aryl groups. 1b is consolidated by weak CH/p interactions. Intra-molecular C-H/O or C-H/N hydrogen bonds and C-H/p may be effective in the stabilization of 2b. Both compounds have showed moderate antimicrobial activity, but 1b exhibits higher activity than 2b. All experimental results are found in good support to theoretical data. Findings of research may be helpful guide for the medicinal chemists and the field is further open for pharmacokinetics studies.
A comparative study of two novel unsymmetrically substituted triazacyclohexanes
(2017-02-27) Hanane Lamraoui
Novel unsymmetrically N-substituted N,N0-R1N00-R2-1,3,5-triazacyclohexanes (1b and 2b; R1 ¼ p-chlorophenyl or p-methoxyphenyl and R2 ¼ butyl or cyclohexyl) have been synthesized in a good yield from condensation reaction by excess amine. Both triazacyclohexane rings have chair conformation. However, 1b adopts diaxial orientation of aryl groups and an equatorial form of alkyl group whereas 2b prefers an axial orientation of the alkyl group and diequatorial forms of aryl groups. 1b is consolidated by weak CH/p interactions. Intra-molecular C-H/O or C-H/N hydrogen bonds and C-H/p may be effective in the stabilization of 2b. Both compounds have showed moderate antimicrobial activity, but 1b exhibits higher activity than 2b. All experimental results are found in good support to theoretical data. Findings of research may be helpful guide for the medicinal chemists and the field is further open for pharmacokinetics studies.
A comparative study of two polymorphs of L-aspartic acid hydrochloride
(2014-06-05) Rim Benali-Cherif; Takouachet Radhwnae; Nourredine Benali-Cherif
A Comparative Theoretical and Spectroscopic Study of Aminomethylbenzoic Acid Derivatives as Potential NLO Candidates †
(2020-12-25) Amani Direm
Three aminomethylbenzoic acid derivatives were theoretically studied at M062X/6-311++G(d,p) level in a vacuum, namely 2-ammonio-5-methylcarboxybenzene perchlorate (1), 4-(ammoniomethyl) carboxybenzene nitrate (2) and 4-(ammoniomethyl)carboxybenze perchlorate (3). The compounds’ structures were fully optimized and compared with the single-crystal X-ray diffraction results, showing a very close agreement with the experimental structural parameters. Their IR, 1H- and 13C-NMR spectra were calculated and examined in detail. Furthermore, the molecular electrostatic potential (MEP) maps of the studied compounds were investigated and the strength of the non-covalent interactions evaluated. In addition to these results, the NLO properties of the three compounds were p
A Discrete Crow Search Algorithm for Mining Quantitative Association Rules
(2021) Abderrahim Siam
Associationrulesarethespecificdataminingmethodsaimingtodiscoverexplicitrelationsbetweenthe differentattributesinalargedataset.However,inreality,severaldatasetsmaycontainbothnumericand categoricalattributes.Recently,manymeta-heuristicalgorithmsthatmimicthenaturearedeveloped forsolvingcontinuousproblems.Thisarticleproposesanewalgorithm,DCSA-QAR,formining quantitativeassociationrulesbasedoncrowsearchalgorithm(CSA).Toaccomplishthis,newoperators aredefinedtoincreasetheabilitytoexplorethesearchingspaceandensurethetransitionfromthe continuoustothediscreteversionofCSA.Moreover,anewdiscretizationalgorithmisadoptedfor numericalattributestakingintoaccountdependenciesprobablythatexistbetweenattributes.Finally, toevaluatetheperformance,DCSA-QARiscomparedwithparticleswarmoptimizationandmono andmulti-objectiveevolutionaryapproachesforminingassociationrules.Theresultsobtainedover real-worlddatasetsshowtheoutstandingperformanceofDCSA-QARintermsofqualitymeasures.
A Low-Cost Platform for Real Time Data Acquisition and Fractional Control with Application to a DC motor
(International Journal of Power Electronics and Drive Systems (IJPEDS), 2023-10-01) Abdel Fettah Berkani, Hemza; Keziz, Bouziane; Lashab, Mohamed; Djouambi, Abdelbaki; Kerrouche, Abdelfateh
This paper presents a low-cost experimental platform for real time data acquisition, identification and fractional order control of some low dynamic systems via Arduino-Simulink interface. As a demonstrative example, a DC motor is considered and modelled as a First Order Plus Time Delay Plant (FOPTD) using data acquisition-based Arduino. Then, simple analytical rules are used to design a robust Fractional Order Controller (FOC) which require a high computing power. Several validation tests of the FOC have been curried out via Arduino–Simulink interface. The experimental results, compared with those obtained with theoretical simulation; confirm that the proposed interface can be used to support research and teaching feedback control systems via experimental investigations on a low-cost laboratory kit.
A Method based on Multi-agent Systems and Passive Replication Technique for Predicting Failures in Cloud Computing
(Bentham Science Publishers, 2023-11-01) Hioual Ouided; Hioual Ouassila; Hemam Sofiane Mounine; Maifi Lyes
Cloud computing refers to the computing capacities of remote computers, where the user has considerable computing power without having to own power units. The probability of failures, which can occur during execution, increases in the number of nodes. Since failures cannot be completely avoided, one solution is to use failure tolerance mechanisms. Predicting failures has become a major task for engineers and software developers, as failure increases resource usage costs. Objectives and Methods: This paper presents a hybrid method of predicting failures in a cloudcomputing environment based on the passive replication technique and multi-agent systems. It detects failures, improves the average response time and minimizes lost time. This method makes it possible to efficiently and transparently guarantee the continuity of cloud computing services in the presence of failures. Results: The results show that the proposed method performs well in the presence of failures, improves the response time and minimizes the additional costs caused by the failures. Conclusion: This paper proposes a hybrid method of predicting failures in cloud-computing based on the passive replication technique and multi-agent systems to detect failures and minimize lost time. The replication technique works by duplicating some system components, which are deployed simultaneously across different resources. This technique aims to make the system robust, increase availability and guarantee the execution of jobs. In addition, it is suitable for long-running tasks.
A Modular Support Vector Machine for Active Learning of Urban Remote Sensing Images Classification in Algeria
(Springer - Journal of the Indian Society of Remote Sensing, 2018) Fouzi Douak
In this work, we present a new strategy of active learning, based on a modular version of support vector machine (MSVM) applied to urban remote sensing images in Algeria. In general, the training set is highly imbalanced, which gives more complex models; this difficulty is solved by dividing the problem at hand into a set of sub-problems, where each sub-model could be simpler to solve. The support vector machine is introduced to solve the problem of classification based on image remote sensing data related to atmospheric conditions and illumination reflectance. The aim of the proposed method is to improve the accuracy in order to understand the correlated elements of urban structures (the site, the built, the parcels, the network, the space), to generate the final classification result. In particular, we propose a new method based on the modular support vector machine (MSVM) adopted to active learning method, using three different clustering methods (i) k-means, (ii) fuzzy c-means (FCM), and (iii) Gustafson–Kessel (GKclust). Experimental results obtained on two QuickBird multispectral images of Se´tif and Batna cities in the eastern of Algeria confirm the capabilities of the proposed methods based on the ensemble of model trained with different task decomposition compared to a traditional model using active learning. This method improves each class presents a main register in urban structure tissues.
A new fractional order controller tuning method based on Bode’s ideal transfer function
(International Journal of Dynamics and Control, 2020-01-23) Bouziane Keziz, Abdelbaki Djouambi & Samir Ladaci
Design of robust controller for multivariable systems is very challenging and their automation is a key concern in control system design. In this paper, a new, simple, and reliable automated fractional-order multivariable Quantitative Feedback Theory (QFT) controllers design methodology is proposed. A fixed structure fractional-order multivariable QFT controller has been synthesized by solving QFT quadratic inequalities of robust stability and tracking specifications. The quadratic inequalities (constraints) are posed as Interval Constraint Satisfaction Problem (ICSP). The constraints are solved by constraint solver-RealPaver. The synthesis problem consists of obtaining a controller that ensures stability and meets a given set of performance specifications, in spite of disturbance and model uncertainties. In addition to perform the above tasks, a MIMO controller also has to perform the difficult task of minimizing interaction between the various control loops. Unlike existing manual or convex optimization based QFT design approaches, the proposed method gives a controller which meets all performance requirements in QFT, without going through the conservative and sequential design stages for each of the multivariable sub-systems. In the design method, we pose the prefilter design problem as an ICSP and solve it using the well-established constraint solver. The designed controllers and prefilters are tested for a quadruple tank process and their efficacy is demonstrated.
A New High Order Theory for Buckling Temperature Analysis of Functionally Graded Sandwich Plates Resting on Elastic Foundations
(CHITOUR mourad, 2022-06-30) CHITOUR mourad
Using a high order theory (HSDT), this work presents a study of thermal buckling of functionally graded (FG) sandwich plates subjected to various temperature rises across their thickness and resting on a twoparameter elastic foundation. The mechanical properties of the FG sandwich plates are supposed to change gradually through the thickness according to a power law (P-FGM). The intermediate layer is homogeneous and made of a purely ceramic material. The principle of virtual works is used to obtain stability equations, and their solutions are obtained based on Navier’s solution technique. The obtained results are compared with other studies in the literature. Then, a parametric study is conducted to investigate the influence of geometric and mechanical characteristics such as the ratios of dimensions (width, length, and thickness), the material index (k), and the effect of the elastic foundation on the critical buckling temperature.
A new pre-whitening transform domain LMS algorithm and its application to speech denoising
(Science Direct, Elsevier Signal Processing, 2016-06-23) CHERGUI Laid; BOUGUEZEL Saad
In this paper, we propose a new pre-whitening transform domain LMS algorithm. The main idea is to introduce a pre-whitening using a simple finite impulse response decorrelation filter of order one before applying the transform to reinforce its decorrelation. The resulting algorithm has the advantage of using any transform even with low decorrelation. This advantage can be exploited to consider transforms having lower computational and structural complexities than those of the classical transforms. For this purpose, we also investigate the use of other transforms, namely the parametric Fourier and Hartley transforms. This investigation is accomplished by studying the eigenvalue spreads obtained by a given parametric transform and then finding the value of the parameter corresponding to the minimum eigenvalue spread, which is equivalent to the best mean square error (MSE) convergence behavior. This approach provides new attractive transforms for the proposed algorithm. Moreover, we consider the adaptive speech denoising as an application to evaluate the performance of the proposed algorithm. The comparisons between the proposed and conventional algorithms for different transforms are performed in terms of the computational complexity, MSE convergence speed, reached steady state level, residual noise in the denoised signal, steady state excess MSE, misadjustment and output SNR.
A new tetranuclear copper(II) complex using a Schiff base ligand: Synthesis, structural, and magnetic studies
(2017-06-01) Amel Messai
This paper reports on the synthesis, X-ray, and magnetic properties of tetranuclear CuII complex [CuL4] with square-like structure. A Schiff base ligand used for synthesis in this work derives from condensation of acetylacetone with DL-valine amino acid. The structure of the synthesized ligand was investigated by FTIR and NMR. Investigation of the crystal packing diagrams demonstrates extensive C–H O interactions of hydrogen bonding, causing to the production of network structures. The complex exhibits exchange interaction among the CuII ions by a bridging carboxylate pathway. Analysis of the magnetic data through spin Hamiltonians of the form H^ ¼ 2Jð^S1^ S4 þ ^S4^S2 þ ^ S2^S3 þ ^S3^ S1Þ 2J0ð^S1^S2 þ ^ S3^S4Þ (J has a positive value for a ferromagnetic interaction and negative value for an antiferromagnetic interaction) lead to the following parameters set of best-fit: J = 3.04 cm 1, J0 = 0 cm 1, g = 2.09, and ZJ = 0.109 cm 1.
A rhodanine derivative as a potential antibacterial and anticancer agent: Crystal structure, spectral characterization, DFT calculations, Hirshfeld surface analysis, in silico molecular docking and ADMET studies
(2023-01-23) Amani Direm
A novel rhodanine derivative, namely 5-(4-dimethylaminobenzylidene) rhodanine “C12H12N2OS2”, was successfully crystallized from condensation route and characterized by NMR, FT-IR, UV–Vis spectral methods as well as single-crystal X-ray diffraction. This rhodanine derivate crystallizes in the monoclinic P21/c space group, with the cell parameters: a = 3.93590(10), b = 11.2480(3), c = 26.6703(7) A˚ and β = 93.8530(10)°. The molecular structure displays intra- (C − S···H) and intermolecular (N − H···O) hydrogen-bonding interactions. Micro-spectroscopy performed on single-crystals of the studied compound revealed the first absorption transition at 2.25 eV, and a well-structured luminescence peaked at 2.01 eV (0.15 eV broad). Density functional theory (DFT) calculations allowed the structure optimization, the electronic properties, the IR-vibrational modes and frequencies as well as the 1H and 13C NMR chemical shifts’ calculation. Furthermore, time-dependent DFT (TD-DFT) calculations were performed for the vertical transition energies. Hirshfeld surface analysis (HSA) showed the presence of non-conventional C–H···H–C, C–H···π and π···lp interactions and π−π stacking. The anti-cancer and anti-bacterial activities of the studied compound towards the Polo-like kinase PLK1 and the Escherichia coli MurB enzymes were in silico evaluated by performing molecular docking simulations. The results suggest that the molecule can significantly inhibit the enzymes’ active sites. Additionally, the physicochemical and pharmacokinetic characteristics of the molecule were evaluated through absorption, distribution, metabolism, excretion and toxicity (ADMET) analysis, and the results ensure its good drug-likeness properties
A rhodanine derivative as a potential antibacterial and anticancer agent: Crystal structure, spectral characterization, DFT calculations, Hirshfeld surface analysis, in silico molecular docking and ADMET studies
(2023-01-23) Amal Guerraoui
A novel rhodanine derivative, namely 5-(4-dimethylaminobenzylidene) rhodanine “C ”, was successfully crystallized from condensation route and characterized by NMR, FT-IR, UV–Vis spectral methods as well as single-crystal X-ray diffraction. This rhodanine derivate crystallizes in the monoclinic P2 1 /c space group, with the cell parameters: a = 3.93590(10), b = 11. 2480( 3) , c = 26.6703(7) ˚ A and β = 93.8530(10)°. The molecular structure displays intra- (C − S···H) and intermolecular (N − H···O) hydrogen-bonding interactions. Micro-spectroscopy performed on single-crystals of the studied compound revealed the ﬁrst absorption transition at 2.25 eV, and a well-structured luminescence peaked at 2.01 eV (0.15 eV broad). Density functional theory (DFT) calculations allowed the structure optimization, the electronic properties, the IR-vibrational modes and frequencies as well as the chemical shifts’ calculation. Furthermore, time-dependent DFT (TD-DFT) calculations were performed for the vertical transition energies. Hirshfeld surface analysis (HSA) showed the presence of non-conventional C–H···H–C, C–H···π and π···lp interactions and π−π stacking. The anti-cancer and anti-bacterial activities of the studied compound towards the Polo-like kinase PLK1 and the Escherichia coli MurB enzymes were in silico evaluated by performing molecular docking simulations. The results suggest that the molecule can signiﬁcantly inhibit the enzymes’ active sites. Additionally, the physicochemical and pharmacokinetic characteristics of the molecule were evaluated through absorption, distribution, metabolism, excretion and toxicity (ADMET) analysis, and the results ensure its good drug-likeness properties. 12 H 1 12 N 2 H and OS 13 2 C NMR
A Robust Fault-Tolerant Predictive Control for Discrete-time Linear Systems Subject to Sensor and Actuator faults
(Sensors, 2021) Sofiane Bououden, Ilyes Boulkaibet, Mohammed Chadli, and Abdelaziz Abboudi
In this paper, a robust fault-tolerant model predictive control (RFTPC) approach is proposed for discrete-time linear systems subject to sensor and actuator faults, disturbances, and input constraints. In this approach, a virtual observer is first considered to improve the observation accuracy as well as reduce fault effects on the system. Then, a real observer is established based on the proposed virtual observer, since the performance of virtual observers is limited due to the presence of unmeasurable information in the system. Based on the estimated information obtained by the observers, a robust fault-tolerant model predictive control is synthesized and used to control discrete-time systems subject to sensor and actuator faults, disturbances, and input constraints. Additionally, an optimized cost function is employed in the RFTPC design to guarantee robust stability as well as the rejection of bounded disturbances for the discrete-time system with sensor and actuator faults. Furthermore, a linear matrix inequality (LMI) approach is used to propose sufficient stability conditions that ensure and guarantee the robust stability of the whole closed-loop system composed of the states and the estimation error of the system dynamics. As a result, the entire control problem is formulated as an LMI problem, and the gains of both observer and robust fault-tolerant model predictive controller are obtained by solving the linear matrix inequalities (LMIs). Finally, the efficiency of the proposed RFTPC controller is tested by simulating a numerical example where the simulation results demonstrate the applicability of the proposed method in dealing with linear systems subject to faults in both actuators and sensors.
A simple synthesis of CuO NPs for photocatalytic applications and theirs structural and optical properties.
(Journal of New Technology and Materials, 2021-10-24) Sabrina Roguai 1; Abdelkader Djelloul 2
In this study, the copper nanoparticles were synthesized by simple co-precipitation method which were obtained by heating at 80°C for photocatalytic application. The microstructural characterization of the nanopowder obtained was performed using X-ray diffraction (XRD), SEM, EDS, and Infrared Spectroscopy (IR). The optical properties of nanoparticles were studied by UV-Visible spectroscopy. XRD studies demonstrated that the formation of CuO monoclinic phase and the average grain size of CuO crystallite were found to be 30 nm. The FTIR spectral analysis showed the characteristics peaks of Cu-O bond. The EDAX result indicated that there were no other elemental impurities present in the prepared CuO nanoparticles. SEM images indicate the morphology as a three-dimensional flower-like structure was successfully prepared for subsequent degradation of methylene blue (MB). With regard to the optical proprieties, the value of the bandgap energy equals 1.34 eV.

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