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Data-Based Filters for Non-Gaussian Dynamic Systems With Unknown Output Noise Covariance

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IEEE/CAA Journal of Automatica Sinica 2024年第4期11卷 866-877页

作者： elham Javanfar Mehdi Rahmani the Department of Electrical Engineering Imam Khomeini International UniversityQazvin ***Iran

This paper proposes linear and nonlinear filters for a non-Gaussian dynamic system with an unknown nominal covariance of the output *** challenge of designing a suitable filter in the presence of an unknown covariance matrix is addressed by focusing on the output data set of the *** that data generated from a Gaussian distribution exhibit ellipsoidal scattering,we first propose the weighted sum of norms(SON)clustering method that prioritizes nearby points,reduces distant point influence,and lowers computational ***,by introducing the weighted maximum likelihood,we propose a semi-definite program(SDP)to detect outliers and reduce their impacts on each *** these weights paves the way to obtain an appropriate covariance of the output ***,two filtering approaches are presented:a cluster-based robust linear filter using the maximum a posterior(MAP)estimation and a clusterbased robust nonlinear filter assuming that output noise distribution stems from some Gaussian noise resources according to the ellipsoidal *** last,simulation results demonstrate the effectiveness of our proposed filtering approaches.

关键词： Data-based filter maximum likelihood estimation unknown covariance weighted maximum likelihood estimation weighted sum-of-norms clustering

Maximizing the potential applications of plasma electrolytic oxidation coatings produced on Mg-based alloys in anti-corrosion,antibacterial,and photocatalytic targeting through harnessing the LDH/PEO dual structure

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Journal of Magnesium and Alloys 2024年第7期12卷 2674-2694页

作者： elham Nikoomanzari Arash Fattah-alhosseini Department of Materials Engineering Faculty of EngineeringBu-Ali Sina UniversityHamedanIran

There is an increasing interest in the development of Mg alloys,both for industrial and biomedical applications,due to their favorable characteristics such as being lightweight and ***,the inadequate corrosion resistance and lack of antibacterial properties pose significant challenges in the industrial and biomedical applications,necessitating the implementation of advanced coating engineering *** electrolytic oxidation(PEO)has emerged as a preferred coating technique because of its distinctive properties and successful surface modification ***,there is a continuous need for further enhancements to optimize the performance and functionalities of protective surface *** integration of layered double hydroxide(LDH)into PEO coatings on Mg alloys presents a promising approach to bolstering protective *** thorough review delves into the latest developments in integrating LDH into PEO coatings for corrosion-related *** particularly emphasizes the significant improvements in corrosion resistance,antibacterial effectiveness,and photocatalytic performance resulting from the incorporation of LDH into PEO *** two key mechanisms that enhance the corrosion resistance of PEO coatings containing LDH are the anion exchangeability of the LDH structure and the pore-sealing ***,the antibacterial activity of PEO coatings with LDH stemmed from the release of antibacterial agents stored within the LDH structure,alterations in pH levels,and the photothermal conversion ***,by incorporating LDH into PEO coatings,new opportunities emerge for tackling environmental issues through boosted photocatalytic properties,especially in the realm of pollutant degradation.

关键词： Mg alloy PEO LDH Corrosion Antibacterial activity Photocatalytic degradation

Effect of Al substitution on phase evolution in synthesized Mg_(2)Cu nanoparticles

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International Journal of Minerals,Metallurgy and Materials 2023年第1期30卷 63-71页

作者： elham Mohseni-Sohi Farshid Kashani Bozorg School of Metallurgy and Materials Engineering College of EngineeringUniversity of TehranTehranPO Box 11155/4563Iran

The effect of Mg replacement with Al on the discharge capacity of Mg_(2)Cu powder mixture was *** mixture of nano-crystalline powder was prepared via mechanical alloying(MA)technique with a high energy planetary ball *** addition,different moles of Al(0.05,0.1,0.15,0.2,and 0.3 M)were substituted to Mg_(2)Cu powder.X-ray diffraction(XRD),scanning electron microscopy(SEM),and transmission electron microscopy(TEM)were used to analyze changes in structure,morphology,and grain *** obtained powder was utilized as an anode in a nickel-metal hydride battery(Ni-MH).In the specimens with 0.05 M Al content,the orthorhombic structure of Mg_(2)Cu is emerged after 5 h *** results reveal that more than 0.1 M Al substitution leads to an appearance of MgCu_(2) *** substi-tution does not affect microstructure uniformity;however,it causes a decrease in crystalline size and lattice *** selected area diffraction(SAD)pattern elucidates that the electrode with the Mg_(1.9)Al_(0.1)Cu chemical composition and 20 h milling has the maximum discharge capacity.

关键词： Mg_(2)Cu mechanical alloying nanocrystalline discharge capacity

Simplified modeling of frequency behavior in photonic crystal vertical cavity surface emitting laser with tunnel injection quantum dot in active region

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Chinese Physics B 2017年第2期26卷 260-267页

作者： Mehdi Riahinasab Vahid Ahmadi elham Darabi Department of Electrical Engineering Science and Research Branch Islamic Azad University Tehran Iran Department of Electrical Engineering Tarbiat Modares University Tehran Iran Plasma Physics Research Center Science and Research Branch Islamic Azad University Tehran Iran

In this work, the characteristics of the photonic crystal tunneling injection quantum dot vertical cavity surface emitting lasers（Ph C-TIQD-VCSEL） are studied through analyzing a modified modulation transfer function. The function is based on the rate equations describing the carrier dynamics at different energy levels of dot and injector well. Although the frequency modulation response component associated with carrier dynamics in wetting layer（WL） and at excited state（ES） levels of dots limits the total bandwidth in conventional QD-VCSEL, our study shows that it can be compensated for by electron tunneling from the injector well into the dot in TIQD structure. Carrier back tunneling time is one of the most important parameters, and by increment of that, the bias current dependence of the total bandwidth will be insignificant. It is proved that at high bias current, the limitation of the WL-ES level plays an important role in reducing the total bandwidth and results in rollovers on 3-d B bandwidth-I curves. In such a way, for smaller air hole diameter of photonic crystal, the effect of this reduction is stronger.

关键词： modulation transfer function photonic crystal(PhC) tunnel injection quantum dot(TIQD) vertical cavity surface emitting laser(VCSEL)

Identification of time-varying system and energy-based optimization of adaptive control in seismically excited structure

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Earthquake Engineering and Engineering Vibration 2024年第1期23卷 227-240页

作者： elham Aghabarari Fereidoun Amini Pedram Ghaderi Department of Civil Engineering Iran University of Science and TechnologyTehran 16844Iran

The combination of structural health monitoring and vibration control is of great importance to provide components of smart *** synthetic algorithms have been proposed,adaptive control that is compatible with changing conditions still needs to be used,and time-varying systems are required to be simultaneously estimated with the application of adaptive *** this research,the identification of structural time-varying dynamic characteristics and optimized simple adaptive control are ***,reduced variations of physical parameters are estimated online using the multiple forgetting factor recursive least squares(MFRLS)***,the energy from the structural vibration is simultaneously specified to optimize the control force with the identified parameters to be *** is also performed based on the probability density function of the energy under the seismic excitation at any ***,the optimal control force is obtained by the simple adaptive control(SAC)algorithm and energy coefficient.A numerical example and benchmark structure are employed to investigate the efficiency of the proposed *** simulation results revealed the effectiveness of the integrated online identification and optimal adaptive control in systems.

关键词： integrated online identification time-varying systems structural energy multiple forgetting factor recursive least squares optimal simple adaptive control algorithm

Synthesis, Characterization and Electrochemical Study of Graphene Oxide-Multi Walled Carbon Nanotube-Manganese Oxide-Polyaniline Electrode as Supercapacitor

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Journal of Materials Science & Technology 2016年第8期32卷 763-773页

作者： Mir Ghasem Hosseini elham Shahryari Electrochemistry Research Laboratory Department of Physical Chemistry Chemistry Faculty University of Tabriz

The synthesis of graphene oxide-multi walled carbon nanotube-manganese oxide-polyaniline namely （GMMP） nanocomposite for application in supercapacitor devices was investigated. Morphology of the nanocomposites was studied by X-ray diffraction （XRD）, Fourier transform infrared （FT-IR） spectrosco- py, scanning electron microscopy （SEM）, transmission electron microscopy （TEM） and energy dispersive X-ray micmanalysis （EDX）. The electrochemical properties of nanocomposite based electrodes were in- vestigated by cyclic voltammetry （CV）, galvanostatic charge-discharge and electrochemical impedance spectroscopy （EIS） techniques in 0.5 mol/L Na2SO4. The specific capacitances of 173.00, 127.85, 87.50, 58.65 and 12.00 （mF cm^-2） were obtained for GMMP, GMP （GO-MWCNT-PANI）, GMM （GO-MWCNT-MnO2）, GM （GO-MWCNT） and G （GO） at a scan rate of 10 mV s^-1, respectively. Also, GMMP nanocomposite re- tained 90% initial capacitance after 200 cycle of charge-discharge. The good electrochemical response of this nanocomposite is due to the combination of the electrical double layer capacitance of GO and MWCNT and the gradual introduction of pseudo-capacitance through the redox processes of PANI, -COOH, -OH （in MWCNT-COOH, GO-COOH and GO-OH） and MnO2. This revealed the synergistic effect of PANI, MnO2, -OH -COOH on the carbon based support.

关键词： Supercapacitor Graphene oxide In-situ polymerization Electrochemical Impedance Spectroscopy (EIS) Polyaniline

Comparison of deep convolutional neural network classifiers and the effect of scale encoding for automated pavement assessment

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Journal of Traffic and Transportation Engineering(English Edition) 2023年第2期10卷 258-275页

作者： elham Eslami Hae-Bum Yun Department of Civil Environmental and Construction EngineeringUniversity of Central FloridaOrlandoFL 32816USA

Deep learning has received a growing interest in recent years for detecting different types of pavement distresses and automating pavement condition assessment.A proper choice of deep learning models is key for successful pavement assessment *** this study,we first present a comprehensive experimental comparison of state-of-the-art image classification models to evaluate their performances on 11 pavement objects *** experiments are conducted in different dimensions of comparison,including deep classifier architecture,effects of network depth,and computational *** convolutional neural network(CNN)classifiers widely used in transportation applications,including VGG16,VGG19,ResNet50,DenseNet121,and a generic CNN(as the control model),are tested with a comprehensive pixel-level annotated dataset for 11 different distress and non-distress classes(UCF-PAVE 2017).In addition,we investigate a simple yet effective approach of encoding contextual information with multi-scale input tiles to classify highly random pavement objects in size,shape,intensity,texture,and *** comparison results show that the multi-scale approach significantly improves the classification accuracy for all compared deep classifiers at a negligible extra computational ***,we provide recommendations of how to improve the classification performance of deep CNNs for automated pavement condition assessment based on the comparison results.

关键词： Road damage detection Automated pavement condition assessment Convolutional neural networks Deep learning Multi-class classification

Taguchi Analysis for Improving Optimization of Integrated Forward/Reverse Logistics

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Journal of the Operations Research Society of China 2023年第3期11卷 529-552页

作者： elham Behmanesh Jürgen Pannek International Graduate School for Dynamics in Logistics University of BremenBremenGermany Faculty of Production Engineering University of BremenBremenGermany BIBA Bremer Institut für Produktion und Logistik GmbH BremenGermany

The distribution–allocation problem is known as one of the most comprehensive strategic *** real-world cases,it is impossible to solve a distribution–allocation problem completely in acceptable *** forces the researchers to develop efficient heuristic techniques for the large-term operation of the whole supply *** techniques provide near optimal solution and are comparably fast particularly for large-scale test *** paper presents an integrated supply chain model which is flexible in the delivery *** solution methodology,we apply a memetic algorithm with a novelty in population *** identify the optimum operating condition of the proposed memetic algorithm,Taguchi method is *** this study,four factors,namely population size,crossover rate,local search iteration and number of iteration,are *** the best level of the considered parameters is the outlook of this research.

关键词： Integrated logistics network Flexible path Memetic algorithm Taguchi analysis

Design aspect of a novel L-shaped pulsed column for liquid–liquid extraction applications: Energy consumption and the characteristics velocity concept

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Chinese Journal of Chemical Engineering 2018年第4期26卷 723-730页

作者： Pouria Amani elham Mohammadi Sahar Akhgar School of Chemical Engineering College of Engineering University of Tehran Chemical Engineering Department Tarbiat Modares University

This article deals with the evaluation of the consumption of energy for a steady state solvent extraction in a novel L-shaped pulsed sieve-plate column, which is highly required for design and optimization of the periodic flow processes for industrial applications. In this regard, a comprehensive evaluation on the energy consumption in case of a pulsed flow for three different chemical systems is conducted and besides the influence of pulsation intensity, the effect of geometrical parameters including the plate spacing and the plate free area is investigated as well. Moreover, the concept of characteristic velocity models at flooding points is evaluated with respect to the variation of pressure drop along the column at different operational conditions.

关键词： Solvent extraction Pulsed plate column Pressure drop Energy consumption Pulsed flow Characteristic velocity