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Acousto-optically driven lensless single-shot ultrafast optical imaging

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Light(Science & Applications) 2022年第4期11卷 628-643页

作者： Mohamed Touil Said Idlahcen Rezki Becheker Denis Lebrun Claude Roze ammar Hideur Thomas Godin ORIA CNRS UMR6614-University de Rouen Normandie-INSA Rouen76800 Saint Etienne du RouvrayFrance

Driven by many applications in a wide span of scientifc fields,a myriad of advanced ultrafast imaging techniques have emerged in the last decade,featuring record-high imaging speeds above a trllion-frame-per-second with long sequence *** bringing remarkable insights into various ultrafast phenomena,their application out of a laboratory environment is however limited in most cases,either by the cost,complexity of the operation or by heavy data *** then report a versatile single-shot imaging technique combining sequentially timed lloptical mapping photography(STAMP)with acousto-optics programmable dispersive fhItering(AOPDF)and digital in-line holography(DIH).On the one hand,a high degree of simplicity is reached through the AOPDF,which enables full control over the acquisition parameters via an electrically driven phase and amplitude spectro-temporal tailoring of the imaging ***,contrary to most single-shot techniques,the frame rate,exposure time,and frame intensities can be independently adjusted in a wide range of pulse durations and chirp values without resorting to complex shaping stages,making the system remarkably agile and *** the other hand,the use of DIH,which does not require any reference beam,allows to achieve an even higher technical simplicity by allowing its lensless operation but also for reconstructing the object on a wide depth of field,contrary to classical techniques that only provide images in a single *** imaging speed of the system as well as its flexibility are demonstrated by visualizing ultrashort events on both the picosecond and nanosecond *** virtues and limitations as welll as the potential improvements of this on-demand ultrafast imaging method are critically discussed.

关键词： simplicity resort bringing

Uncertainty analysis of hydrological modeling in a tropicalarea using different algorithms

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Frontiers of Earth Science 2018年第4期12卷 661-671页

作者： ammar RAFIEI EMAM Martin KAPPAS Steven FASSNACHT Nguyen Hoang Khanh LINH Department of Cartography GIS and Remote SensingUniversity of Goettingen37077GoettingenGermany Colorado State University Fort CollinsCO 80523-1476USA Faculty of Land Resources and Agricultural Environment (FLRAE) Flue University of Agriculture and Forestry (F1UAF)Hue UniversityHue City 0084Vietnam

Hydrological modeling outputs are subject to uncertainty resulting from different sources of errors (e.g., error in input data, model structure, and model parameters), making quantification of uncertainty in hydrological modeling imperative and meant to improve reliability of modeling results. The uncertainty analysis must solve difficulties in calibration of hydrological models, which further increase in areas with data scarcity. The purpose of this study is to apply four uncertainty analysis algorithms to a semi-distributed hydrological model, quantifying different source of uncertainties (especially parameter uncertainty) and evaluate their performance. In this study, the Soil and Water Assessment Tools (SWAT) eco-hydrological model was implemented for the watershed in the center of Vietnam. The sensitivity of parameters was analyzed, and the model was calibrated. The uncertainty analysis for the hydrological model was conducted based on four algorithms: Generalized Likelihood Uncertainty Estimation (GLUE), Sequential Uncertainty Fitting (SUFI), Parameter Solution method (ParaSol) and Particle Swarm Optimization (PSO). The performance of the algorithms was compared using P-factor and Rfactor, coefficient of determination (R2), the Nash Sutcliffe coefficient of efficiency (NSE) and Percent Bias (PBIAS). The results showed the high performance of SUFI and PSO with P-factor>0.83, R-factor 0.91, NSE>0.89, and 0.18<0.32. Hence, we would suggest to use SUFI-2 initially to set the parameter ranges, and further use PSO for final analysis. Indeed, the uncertainty analysis must be accounted when the outcomes of the model use for policy or management decisions.

关键词： SWAT-CUP GLUE SUFI2 ParaSol PSO Vietnam

Synthesis of Zeolite Imidazolate Frameworks Mateuial and Used as an Efficient Heterogeneous Catalyst for Various Chemical Reactions

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Synthesis of Zeolite Imidazolate Frameworks Mateuial and Use...

作者： Muhammad ammar（阿马尔）北京化工大学

学位级别：硕士

The porous material is a significant segment of the economy, it is in general consideration to develop and design porous material to have versatile properties such as well-defined structure, tunable pore size, high porosity and highly thermal and chemical stability to perform different type of commercial and industrial applications. For last couple of decades, there is lot of effects has been done to discover and explore new porous materials. Metal organic frameworks (MOFs) materials attained much more interest due to their extraordinary structures and properties with their capability for different applications. In his research work, we selected Zeolite Imidazole Frameworks (ZIFs) materials which possess crystal structure like zeolite materials, is a type of MOFs materials. We focused on the synthesis of ZIF-67, heteropoly acid encapsulated into ZIF-67cage and ZIF-8materials and give their applications in the Friedel-Crafts acylation reactions as an efficient heterogeneous catalyst.Initially, this work demonstrated the synthesis of ZIF-67materials which containing cobalt as metal ions and2-methylimidazole as ligand, triethylamine is used as deprotonated the ligand. ZIF-67is synthesized with different metal:ligand:TEA molar ratios along with metal:ligand ratio at room temperature. Various characterization techniques are utilized such as X-ray powder diffraction abbreviated as XRD, Fourier transform infrared spectroscopy abbreviated as FT-IR, Scanning electron microscopy abbreviated as SEM, Nitrogen adsorption-desorption as well as Thermo-gravimetric analysis (TGA) to explore the characteristics of synthesized ZIF-67samples. The catalytic performance of synthesized ZIF-67is investigated in Friedel-Crafts (FC) acylation reaction of anisole by means of benzoyl chloride as acylating agent. The performance of ZIF-67(metal:ligand molar ratio1:8) sample as catalyst is found better as compare to other ZIF-67samples which involve TEA as deprotonated the ligand.45%conversi

关键词： Metal Organic Framework Zeolite ImidazolateFramework (ZIF-8) Zeolite Imidazolate Framework (ZIF-67) Friedel-Crafts acylation Phosphotungstic acid Catalytic performance

Microwave-assisted catalytic oxidative desulfurization of gasoil fuel using synthesized CuO-ZnO nanocomposites

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燃料化学学报 2019年第9期47卷 1075-1082页

作者： Mustafa H.Fadhil Saad H.ammar Marwa F.Abdul Jabbar Chemical Engineering Department Al-Nahrain University

Recently, organosulfur removal from liquid petroleum fuels is very significant aspect of environment protecting and fuel cell requests. Therefore, improved approaches to remove sulfur are still essential. In the present work, a simple catalytic oxidative desulfurization (CODS) system for Iraqi gasoil fraction has been successfully developed using CuO-ZnO nanocomposites as catalysts, and H 2O 2 as oxidant under microwave irradiation. The main reaction parameters influencing sulfur conversion including microwave power, irradiation time, catalyst dosage and H 2O 2 to gasoil volume ratio have been investigated. The CuO-ZnO nanocomposites was synthesized with different weight ratios and characterized by XRD, FE-SEM, AFM and BET surface area methods. The results reveal that, high sulfur conversion (93%) has been achieved under suitable conditions of microwave CODS as follows: microwave power of 540 W, irradiation time of 15 min, catalyst dosage of 8 g/L (0.4 g), and H 2O 2 ∶gasoil volume ratio of 0.3. The catalyst reusability shows that the synthesized catalyst can be reused five times without an important loss in its activity.

关键词： microwave oxidative desulfurization nanocomposites catalyst gasoil

Physics-Based Active Learning for Design Space Exploration and Surrogate Construction for Multiparametric Optimization

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Communications on Applied Mathematics and Computation 2024年第3期6卷 1899-1923页

作者： Sergio Torregrosa Victor Champaney Amine ammar Vincent Herbert Francisco Chinesta PIMM Arts et Metiers Institute of Technology151 Boulevard de l'Hopital75013 ParisFrance STELLANTIS Route de Gisy78140 Velizy-VillacoublayFrance ESI Chair PIMMArts et Metiers Institute of Technology151 Boulevard de l'Hopital75013 ParisFrance ESI Chair LAMPAArts et Metiers Institute of Technology2 Boulevard du Ronceray49035 AngersFrance

The sampling of the training data is a bottleneck in the development of artificial intelligence(AI)models due to the processing of huge amounts of data or to the difficulty of access to the data in industrial *** learning(AL)approaches are useful in such a context since they maximize the performance of the trained model while minimizing the number of training *** smart sampling methodologies iteratively sample the points that should be labeled and added to the training set based on their informativeness and *** judge the relevance of a data instance,query rules are *** this paper,we propose an AL methodology based on a physics-based query *** some industrial objectives from the physical process where the AI model is implied in,the physics-based AL approach iteratively converges to the data instances fulfilling those objectives while sampling training ***,the trained surrogate model is accurate where the potentially interesting data instances from the industrial point of view are,while coarse everywhere else where the data instances are of no interest in the industrial context studied.

关键词： Active learning(AL) Artificial intelligence(AI) Optimization Physics based

Cyberbullying Detection and Recognition with Type Determination Based on Machine Learning

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Computers, Materials & Continua 2023年第6期75卷 5307-5319页

作者： Khalid M.O.Nahar Mohammad Alauthman Saud Yonbawi ammar Almomani Computer Science Department Yarmouk UniversityIrbidJordan Department of Information Security Faculty of Information TechnologyUniversity of PetraAmmanJordan Software Engineering Department University of JeddahJeddahKSA Research and Innovation Department Skyline University CollegeP.O.Box 1797SharjahUAE IT Department-Al-Huson University College Al-Balqa Applied UniversityP.O.Box 50IrbidJordan

Social media networks are becoming essential to our daily activities,and many issues are due to this great involvement in our *** is a social media network issue,a global crisis affecting the victims and society as a *** results from a misunderstanding regarding freedom of *** this work,we proposed a methodology for detecting such behaviors(bullying,harassment,and hate-related texts)using supervised machine learning algo-rithms(SVM,Naïve Bayes,Logistic regression,and random forest)and for predicting a topic associated with these text data using unsupervised natural language processing,such as latent Dirichlet *** addition,we used accuracy,precision,recall,and F1 score to assess prior *** show that the use of logistic regression,support vector machine,random forest model,and Naïve Bayes has 95%,94.97%,94.66%,and 93.1%accuracy,respectively.

关键词： Cyberbullying social media naïve bayes support vector machine natural language processing LDA

Intelligent Transmission Control for Efficient Operations in SDN

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Computers, Materials & Continua 2022年第5期71卷 2807-2825页

作者： Reem Alkanhel Abid Ali Faisal Jamil Muzammil Nawaz Faisal Mehmood ammar Muthanna Department of Information Technology College of Computer and Information SciencesPrincess Nourah Bint Abdulrahman UniversityRiyadhSaudi Arabia Department of Computer Science University of Engineering and TechnologyTaxila47080Pakistan Department of Computer Science Govt.Akhtar Nawaz Khan(Shaheed)Degree College KTSHaripur22620Pakistan Department of Computer Engineering Jeju National UniversityJeju-siJeju Special Self-Governing Province63243Korea School of Information and Communication Engineering Zhengzhou UniversityChina Department of Telecommunication Networks and Data Transmission The Bonch-Bruevich Saint-Petersburg State University of Telecommunications193232Saint PetersburgRussia Peoples Friendship University of Russia(RUDN University)6 Miklukho-Maklaya St Moscow117198Russian Federation

Although the Software-Defined Network(SDN)is a well-controlled and efficient network but the complexity of open flow switches in SDN causes multiple *** solutions have been proposed so far for the prevention of errors and mistakes in it but yet,there is still no smooth transmission of pockets from source to destination specifically when irregular movements follow the destination host in SDN,the errors include packet loss,data compromise *** accuracy of packets received at their desired destination is possible if networks for pockets and hosts are monitored instead of analysis of network snapshot statistically for the state,as these approaches with open flow switches,discover bugs after their *** article proposes a design to achieve the said objective by defining the Intelligent Transmission Control Layer(ITCL)*** monitors all the connections of end hosts at their specific locations and performs necessary settlements when the connection state changes for one or multiple *** layer informs the controller regarding any state change at one period and controller collects information of end nodes reported via ***,updates flow tables accordingly to accommodate a location-change scenario with a routechange *** is organized on prototype-based implementation using the popular POX *** this paper,it has been discovered that ITCL produces efficient performance in the trafficking of packets and controlling different states of SDN for errors and packet loss.

关键词： Software-defined network ITCL POX open flow

A linear quadratic regulator control of a stand-alone PEM fuelcell power plant

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Frontiers in Energy 2014年第1期8卷 62-72页

作者： Amar BENAISSA Boualaga RABHI ammar MOUSSI Dahmani AISSA Department of Electrical Engineering University of Djelfa cit6 ain chih17000 Algeria MSE Laboratory University of Biskra B.P.145 Biskra 07000 Algeria LARHYS Laboratory University of Biskra B.P.145 Biskra 07000Algeria Thermal Power Station of M'sila M'sila 28000 Algeria

This paper introduces a technique based on linear quadratic regulator （LQR） to control the output voltage at the load point versus load variation from a stand- alone proton exchange membrane （PEM） fuel cell power plant （FCPP） for a group housing use. The controller modifies the optimal gains ki by minimizing a cost function, and the phase angle of the AC output voltage to control the active and reactive power output from an FCPP to match the terminal load. The control actions are based on feedback signals from the terminal load, output voltage and fuel cell feedback current. The topology chosen for the simulation consists of a 45 kW proton exchange membrane fuel cell （PEMFC）, boost type DC/ DC converter, a three-phase DC/AC inverter followed by an LC filter. Simulation results show that the proposed control strategy operated at low commutation frequency （2 kHz） offers good performances versus load variations with low total harmonic distortions （THD）, which is very useful for high power applications.

关键词： modeling of proton exchange membrane fuel cell (PEMFC) controlling of PEMFC. linear quadraticregulator (LQR) DC/DC converter DC/AC inverter

Isolation Enhancement in a Compact Four-Element MIMO Antenna for Ultra-Wideband Applications

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Computers, Materials & Continua 2023年第4期75卷 911-925页

作者： Awais Khan Shahid Bashir Salman Ghafoor Hatem Rmili Jawad Mirza ammar Ahmad Department of Electrical Engineering University of Engineering and TechnologyPeshawar25000Pakistan Department of Electrical Engineering University of Science and TechnologyBannu28100Pakistan School of Electrical Engineering and Computer Science(SEECS) National University of Sciences and Technology(NUST)Islamabad44000Pakistan Electrical and Computer Engineering Department Faculty of EngineeringKing Abdulaziz UniversityJeddahSaudi Arabia K.A.CARE Energy Research and Innovation Center King Abdulaziz UniversityJeddah21589Saudi Arabia SEECS Photonic Research Group National University of Sciences and TechnologyIslamabad44000Pakistan

Mutual coupling reduction or isolation enhancement in antenna arrays is an important area of research as it severely affects the performance of an *** this paper,a new type of compact and highly isolated Multiple-Input-Multiple-Output(MIMO)antenna for ultra-wideband(UWB)applications is *** design consists of four radiators that are orthogonally positioned and confined to a compact 40×40×0.8 mm3 *** final antenna design uses an inverted L shape partial ground to produce an acceptable reflection coefficient(S1120 db for majority of the UWB *** antenna was fabricated and tested with the vector network analyzer(VNA)and in an anechoic chamber for scattering parameters and radiation ***,different MIMO diversity performance metrics are also measured to validate the proposed *** simulation results and the experimental results from the constructed model agree quite *** proposed antenna is compared with similar designs in recently published literature for various performance *** of its low envelope correlation coefficient(ECC9.99 dB),peak gain of 4.6 dB,reduced channel capacity loss(CCL<0.4 b/s/Hz),and average radiation efficiency of over 85%,the proposed MIMO antenna is ideally suited for practical UWB applications.

关键词： Multiple input multiple output antennas envelope correlation coefficient defected ground structure ultra wide band diversity gain