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Robust Controller Synthesis and Analysis in Inverter-Dominant Droop-Controlled Islanded Microgrids

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IEEE/CAA Journal of Automatica Sinica 2021年第8期8卷 1401-1415页

作者： S.mohsen Azizi School of Applied Engineering and Technology and the Department of Electrical and Computer EngineeringNew Jersey Institute of TechnologyNJ 07102 USA

This work investigates the problem of controller design for the inverters in an islanded ***-synthesis controllers and local droop controllers are designed to regulate the output voltages of inverters and share power among them,*** designed controllers alleviate the need for additional sensors to measure the states of the system by relying only on output *** is shown that the designed-synthesis controller properly damps resonant oscillations,and its performance is robust to the control-loop time delay and parameter *** stability of a droop-controlled islanded microgrid including multiple distributed generation(DG)units is analyzed by linearizing the nonlinear power flow model around the nominal operating point and applying theorems from linear *** is indicated that the droop controller stabilizes the microgrid system with dominantly inductive tie-line impedances for all values of resistive-inductive loads,while for the case of resistive-capacitive loads the stability is conditioned on an upper bound on the load *** robust performance of the designed-synthesis controller is studied analytically,compared with the similar analysis in an control(benchmark)framework,and verified by simulations for a four DG benchmark ***,the robustness of the droop controllers is analyzed by Monte Carlo simulations in the presence of local voltage fluctuations and phase differences among neighboring DGs.

关键词： Droop control inverter microgrid Monte Carlo simulation robust control μ-synthesis

Hydrodynamic and heat transfer properties of magnetic fluid in porous medium considering nanoparticle shapes and magnetic field-dependent viscosity

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Chinese Journal of Chemical Engineering 2020年第2期28卷 329-339页

作者： mohsen Izadi Masoud Javanahram Seyed mohsen Hashem Zadeh Dengwei Jing Mechanical Engineering Department Lorestan UniversityKhorramabadIran Mechanical Engineering Department Islamic Azad UniversityBushehrIran Department of Mechanical Engineering Shahid Chamran University of AhvazIran School of Energy and Power Engineering State Key Lab of Multiphase Flow in Power EngineeringXi'an Jiaotong UniversityXi'an 710049China

The purpose of this paper is to study the characteristics of the combined convection heat transfer and a micropolar nanofluid flow passing through an impermeable stretching sheet in a porous *** nanofluid flow field is affected by a magnetic field perpendicular to the *** dynamic viscosity of the micropolar nanofluid changes under the influence of the magnetic *** continuity,linear momentum,angular momentum,and energy equations are first simplified using the order of magnitude technique that,along with the applied boundary conditions and the definition of the appropriate parameters,are transferred to the similarity space using the similarity *** the resulting equations are solved using the Runge–Kutta *** distinction of the macroscale and microscale flow fields and temperature fields resulting from different nanoparticle shapes was *** the Hartmann number,the vortex viscosity parameter,the magnetic parameter,the nanoparticle volume fraction,and the permeability parameter of the porous media increased the surface friction on the *** the vortex viscosity parameter,the magnetic parameter,and the volume fraction of the nanoparticles increases the Nusselt number.

关键词： MHD-combined convection Porous media Magnetic micropolar nanofluid

Development of Voice Control Algorithm for Robotic Wheelchair Using MIN and LSTM Models

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Computers, Materials & Continua 2022年第11期73卷 2441-2456页

作者： mohsen Bakouri Department of Medical Equipment Technology College of Applied Medical ScienceMajmaah UniversityMajmaah City11952Saudi Arabia Department of Physics College of ArtsFezzan UniversityTraghen71340Libya

In this work,we developed and implemented a voice control algorithm to steer smart robotic wheelchairs(SRW)using the neural network *** technique used a network in network(NIN)and long shortterm memory(LSTM)structure integrated with a built-in voice recognition *** Android Smartphone application was designed and configured with the proposed method.A Wi-Fi hotspot was used to connect the software and hardware components of the system in an offline *** operate and guide SRW,the design technique proposed employing five voice commands(yes,no,left,right,no,and stop)via the Raspberry Pi and DC *** native Arabic speakers trained and validated an English speech corpus to determine the method’s overall *** design method of SRW was evaluated in both indoor and outdoor environments in order to determine its time response and *** results showed that the accuracy rate for the system reached 98.2%for the five-voice commends in classifying voices *** interesting finding from the real-time test was that the root-mean-square deviation(RMSD)for indoor/outdoor maneuvering nodes was 2.2∗10–5(for latitude),while that for longitude coordinates was a whopping 2.4∗10–5(for latitude).

关键词： Network in network long short-term memory voice recognition wheelchair

Programmable structured surfaces can change the future of wireless communications

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Light(Science & Applications) 2022年第7期11卷 1341-1342页

作者： Lei Xu mohsen Rahmani Advanced Optics and Photonics Laboratory Department of EngineeringSchool of Science and TechnologyNottingham Trent UniversityNottingham NG118NSUK

An innovative time-varying metasurface has been reported to realise dual-channel data transmissions for light-to-microwave signal *** a novel technique is a remarkable step forward to realise full-spectrum networks for catering for the growing demand for wireless ***,this technique enriches the functionalities of tunable metasurfaces and stimulates new information-oriented applications.

关键词： wireless tunable surfaces

Organosoluble Aliphatic-Aromatic Poly(ether-amide)s Based on Pyridine Moiety in the Main Chain: Synthesis, Characterization and Thermal Studies

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Chinese Journal of Polymer Science 2014年第6期32卷 758-767页

作者： mohsen Hajibeygi Meisam Shabanian Young Researchers Club Varamin Pishva Branch Islamic Azad University Department of Chemistry Farahan Branch Islamic Azad University

A series organosoluble and heterocyclic poly（ether-amide）s （PEA）s were synthesized from a new diamine containing pyridine moiety and four aliphatic-aromatic dicarboxylic acids by direct polycondensation reactions. Dicarboxilic acids 4a-4d containing ether groups were synthesized in two step reactions. At first, dialdehydes 3a-3d were synthesized from four dibromo alkanes la-ld and 4-hydroxybenzaldehyde 2, then dicarboxilic acids 4a-4d were synthesized from dialdehydes 3a-3d and malonic acid in a solvent free reaction. On the other hand, the new diamine 8 containing pyridine ring was synthesized in two step reactions. The structures of synthesized monomers and polymers were proven by FTIR, NMR spectroscopy and elemental analysis. Also all of the above polymers were fully characterized by inherent viscosity, solubility tests, gel permeation chromatography （GPC）, differential scanning calorimetry （DSC） and thermogravimetric analysis （TGA）. The resulted PEAs have shown good inherent viscosities, solubility and thermal properties.

关键词： Poly(ether-amide) Organosoluble Aliphatic-aromatic Polycondensation Malonic acid.

Flow-injection spectrophotometric determination of vanadium with malachite green oxalate by bromate in acidic and micellar medium

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Rare Metals 2011年第3期30卷 216-221页

作者： mohsen Keyvanfarda Narges Abedib Faculty of Science Majlesi BranchIslamic Azad University Group of Chemistry Shahreza BranchIslamic Azad University

A flow injection method is proposed for determining vanadium（V）. The method is based on its catalytic effect on the oxidation of malachite green oxalate by bromate. The reaction was monitored spectrophotometrically by measuring malachite green oxalate absorbance at λmax = 625 nm. The reagents and manifold variables, which have influences on the sensitivity, were investigated and the optimum conditions were established. The optimized conditions made it possible to determine vanadium in the ranges of 10-140 ng/mL with a detection limit of 5.2 ng/mL and a sample rate of 20 ± 5 samples/h.

关键词： vanadium flow injection analysis malachite green oxalate spectrophotometry micellar medium

OPTICALLY ACTIVE AND FLAME-RETARDANT POLY(AMIDE-IMIDE)S BASED ON PHOSPHINE OXIDE MOIETY AND N,N′-(PYROMELLITOYL)BIS-L-AMINO ACID IN THE MAIN CHAIN:SYNTHESIS AND CHARACTERIZATION

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Chinese Journal of Polymer Science 2010年第4期28卷 517-525页

作者： Khalil Faghihi mohsen Hajibeygi Organic Polymer Chemistry Research Laboratory Department of ChemistryFaculty of ScienceArak UniversityArak 38156Iran

Six new optically active and flame-retardant poly（amide-imide）s PAls 5a-5f containing phosphine oxide moiety as a flame-retardant unit in the main chain were synthesized from direct polycondensation reaction of six chiral N,N＇-（pyromellitoyl）-bis-L-amino acid 3a-3f with bis（3-aminophenyl）phenyl phosphine oxide 4 in a medium consisting of N-methyl-2-pyrrolidone （NMP）, triphenyl phosphite （TPP）, calcium chloride （CaCl2） and pyridine. The polymerization reactions produced a series of optically active poly（amide-imide）s with good yield and good inherent viscosity of 0.34-0.70 dLg^-1. The resulted polymers were fully characterized by means of FTIR and ^1H-NMR spectroscopy, gel permeation chromatography （GPC）, elemental analyses, inherent viscosity and solubility tests. Thermal properties and flameretardant behavior of the PAIs 5a-5f were investigated using thermal gravimetric analysis （TGA and DTG） and limiting oxygen index （LOI）. Data obtained by thermal analysis （TGA and DTG） revealed that these polymers showed good thermal stability. Furthermore, high char yield in TGA and good LOI values indicated that the resulting polymers were capable of exhibiting good flame retardant properties. N,N＇-（pyromellitoyl）-bis-L-amino acids 3a-3f were prepared in quantitative yields by the condensation reaction of pyromellitic dianhydride （1,2,4,5-benzenetetracarboxylicacid-1,2,4,5-dianhydride） 1 with L-alanine 2a, L-valine 2b, L-leucine 2c, L-isoleucine 2d, L-phenyl alanine 2e and L-2-aminobutyric acid 2f in acetic acid solution.

关键词： Optically active Flame-retardant polymers Poly(amide-imide)s Limiting oxygen index

Optimal seismic design of reinforced concrete structures under timehistory earthquake loads using an intelligent hybrid algorithm

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Earthquake Engineering and Engineering Vibration 2015年第1期14卷 97-109页

作者： Sadjad Gharehbaghi mohsen Khatibinia Department of Civil Engineering Behbahan Khatam Alanbia University of Technology Department of Civil Engineering University of Birjand

A reliable seismic-resistant design of structures is achieved in accordance with the seismic design codes by designing structures under seven or more pairs of earthquake records. Based on the recommendations of seismic design codes, the average time-history responses （ATHR） of structure is required. This paper focuses on the optimal seismic design of reinforced concrete （RC） structures against ten earthquake records using a hybrid of particle swarm optimization algorithm and an intelligent regression model （IRM）. In order to reduce the computational time of optimization procedure due to the computational efforts of time-history analyses, IRM is proposed to accurately predict ATHR of structures. The proposed IRM consists of the combination of the subtractive algorithm （SA）, K-means clustering approach and wavelet weighted least squares support vector machine （WWLS-SVM）. To predict ATHR of structures, first, the input-output samples of structures are classified by SA and K-means clustering approach. Then, WWLS-SVM is trained with few samples and high accuracy for each cluster. 9- and 18-storey RC frames are designed optimally to illustrate the effectiveness and practicality of the proposed IRM. The numerical results demonstrate the efficiency and computational advantages of IRM for optimal design of structures subjected to time-history earthquake loads.

关键词： optimal seismic design reinforced concrete frames earthquake loads particle swarm optimization intelligent regression model support vector machine

Reliability analysis of production schedule in multi-element deposits under grade-tonnage uncertainty with multi-destinations for the run of mine material

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International Journal of Mining Science and Technology 2019年第3期29卷 483-489页

作者： mohsen Jamshidi Morteza Osanloo Department of Mining and Metallurgical Engineering Amirkabir University of Technology

Blending contributes to create an opportunity to achieve the target feed material and helps optimize the run of mine(ROM)*** addition,it allows mixing different materials and achieving a wide range of ***,multiple destinations can be considered for *** present study seeks to develop a Mixed Integer Programming(MIP)model for the production scheduling of an iron ore *** on this model,different destinations are considered for mine products with different *** this aim,ten scenarios were considered with a number of different *** results indicated that the maximum NPV in the multiple product scenarios is about 15%more than that of the single product ***,30 realizations were used to evaluate the effect of grade and tonnage *** reliability of the production plan was approximately 61.07%and 62.81%in the first and second period of exploitation,respectively.

关键词： Production Blending Multiple products Reliability Mixed Integer Programming model