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Evaluation of a novel Asymmetric Genetic Algorithm to optimize the structural design of 3D regular and irregular steel frames

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Frontiers of Structural and Civil Engineering 2020年第5期14卷 1110-1130页

作者： Mohammad Sadegh ES-haghi Aydin SHISHEGARAN Timon RABCZUK School of Civil Engineering Khajeh Nasir Toosi University of TechnologyTehran 19697-64499Iran School of Civil Engineering Iran University of Science and TechnologyTehran 13114-16846Iran Division of Computational Mechanics Ton Duc Thang UniversityHo Chi Minh CityVietnam Faculty of Civil Engineering Ton Duc Thang UniversityHo Chi Minh CityVietnam

We propose a new algorithm,named Asymmetric Genetic Algorithm(AGA),for solving optimization problems of steel *** AGA consists of a developed penalty function,which helps to find the best generation of the *** objective function is to minimize the weight of the whole steel structure under the constraint of ultimate loads defined for structural steel buildings by the American Institute of Steel Construction(AISC).Design variables are the cross-sectional areas of elements(beams and columns)that are selected from the sets of side-flange shape steel sections provided by the *** finite element method(FEM)is utilized for analyzing the behavior of steel frames.A 15-storey three-bay steel planar frame is optimized by AGA in this study,which was previously optimized by algorithms such as Particle Swarm Optimization(PSO),Particle Swarm Optimizer with Passive Congregation(PSOPC),Particle Swarm Ant Colony Optimization(HPSACO),Imperialist Competitive Algorithm(ICA),and Charged System Search(CSS).The results of AGA such as total weight of the structure and number of analyses are compared with the results of these *** performs better in comparison to these algorithms with respect to total weight and number of *** addition,five numerical examples are optimized by AGA,Genetic Algorithm(GA),and optimization modules of SAP2000,and the results of them are *** results show that AGA can decrease the time of analyses,the number of analyses,and the total weight of the *** decreases the total weight of regular and irregular steel frame about 11.1%and 26.4%in comparing with the optimized results of SAP2000,respectively.

关键词： optimization steel frame Asymmetric Genetic Algorithm constraints of ultimate load constraints of serviceability limits penalty function

In-situ fabrication of Al(Zn)-Al_2O_3 graded composite using the aluminothermic reaction during hot pressing

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International Journal of Minerals,Metallurgy and Materials 2018年第7期25卷 832-839页

作者： s.m.a.haghi s.a.sajjadi a.babakhani Department of Materials Science and Engineering Engineering facultyFerdowsi University of MashhadMashhadIra

In INs study, the fabrication of multilayer AI（Zn）-A1203 with different volume fractions of A1203 was investigated. A1 and ZnO powders were milled by a plaaetaxy ball mill, after which five-layer functionally graded samples were produced flarough hot pressing at 580~C and 90 MPa pressure for 30 min. Formation of reinforcing A1203 particles occurred in the aluminum matrix via the aluminolkermic reaction. Determination of the ignition temperature of the aluminolkennic reaction was accomplished using differential lkermal and lkermo- gravimelric amlyses. Scaaming electron microscopy, energy dispersive spectroscopy, and X-ray diffractometery amlyses were utilized to characterize the specimens. The lkermal amlysis results showed that the ignition temperatures for the aluminolkennic reaction of layers with the highest and lowest ZnO contents were 667 and 670~C, respectively. Microslxuctural observation and chemical amlysis confirmed the fa- brication of AI（Zn）-A1203 functionally graded materials composites with precipitation of additional Zn in the matrix. Moreover, nearly dense functionally graded samples demonstrated minimum and maximum hacdness values of HV 75 and HV 130, respectively.

关键词： metal-matrix composites functionally graded composites fllermogravimet^ic analysis powder processing sintering

Signal promoting role of a p-type transition metal dichalcogenide used for the detection of ultra-trace amounts of diclofenac via a labeled aptasensor

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Frontiers of Chemical Science and Engineering 2019年第4期13卷 823-831页

作者： Abdolhamid Hatefi-Mehrjardi Amirkhosro Beheshti-Marnani Zarrin Es'haghi Department of Chemisttry Payamc Noor University(PNU)TehranIran

A p-type transition metal dichalcogenide(WS2)was synthesized and hybridized with graphene oxide via a simple hydrothermal *** as-prepared material was used to modify a glassy carbon electrode for the fabrication of a simple,stable,and repeatable methylene blue-labeled“signal-off”aptasensor used for the sensitive determination of very low amounts of sodium diclofenac(DCF).The synthetic material,modification process,and role of WS2 in the current response enhancement were studied by X-ray diffraction,energy-dispersive X-ray spectroscopy,field emission scanning electron microscopy,high resolution transmission electron microscopy,Hall effect,cyclic voltammetry,differential pulse voltammetry,and electrochemical impedance ***,a wide linear range of DCF concentration(0.5-300 nmol/L),very low limit of detection(0.23 nmol/L),and good selectivity were obtained using the differential pulse voltammetry method with the assembled ***,the fabricated aptasensor was successfully developed for physiological real samples with significant recoveries.

关键词： labeled aptasensor transition metal dichalcogenide graphene oxide sodium diclofenac

Characteristic Assessment of Stabilized Polyacrylonitrile Nanowebs for the Production of Activated Carbon Nano-Sorbents

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Chinese Journal of Polymer Science 2014年第4期32卷 449-457页

作者： S.Rafiei B.Noroozi Sh.Arbab A.K.haghi Department of Textile Engineering University of Guilan

Polyacrylonitrile （PAN） nanofibers with average diameter of 300 nm were produced by electro-spinning. The nanofibers were stabilized at different temperatures in the range of 180-270 ℃in several duration times and heating rates. Fourier transforms infrared （FTIR） spectroscopy, differential scanning calorimetry （DSC） and X-ray diffraction （XRD） analyzing techniques were employed to measure the extent of stabilization reaction. By all procedures, the ranges of temperature and duration time recommended were about 250-270 ℃ and 1-2 h, respectively. Increasing the activation temperature from 800 ℃ to 1200 ℃ caused porosity and pore volume development up to 60% and 0.532 cm3/g, respectively. Pore width of all samples was calculated to be about 0.7 nm confirming micro-pore structure of the produced PAN based activated carbon nanofibers. Comparing dye adsorption for different adsorbents including chitin and granular activated carbon （GAC） showed the highest efficiency for the produced activated carbon nanofibers （ACNFs）.

关键词： Polyacrylonitrile Electro-spinning Stabilization Activated carbon nanofibers Adsorbent.

Pulmonoprotective Action of Zataria multiflora Ethanolic Extract on Cyclophosphamide-Induced Oxidative Lung Toxicity in Mice

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Chinese Journal of Integrative Medicine 2020年第10期26卷 754-761页

作者： Emran Habibi Mohammad Shokrzadeh Amirhossein Ahmadi Aroona Chabra Farshad Naghshvar Hamed haghi-AminjarP and Fatemeh Salehi Pharmaceutical Sciences Research Center Faculty of PharmacyMazandaran University of Medical SciencesSari(48175-861)Iran Department of Pharmacognosy Faculty of PharmacyMazandaran University of Medical SciencesSari(48175-861)Iran Department of Toxicology and Pharmacology Faculty of PharmacyMazandaran University of Medical SciencesSari(48175-861)Iran Student Research Committee Faculty of PharmacyMazandaran University of Medical SciencesSari(48175-861)Iran Department of Pathology Faculty of MedicineMazandaran University of Medical SciencesSari(48471-91971)Iran

Objective To evaluate the protective effect of Zataria multiflora extract,an antioxidative medicinal plant,against cyclophosphamide(CP)-induced oxidative lung damage in *** Mice were intraperitoneally pre-treated with various doses of Zataria multiflora extract(50,100,200,and 400 mg/kg)once daily for 7 consecutive *** were then injected with a single 200 mg/kg intraperitoneal dose of CP 1 h after the last administration of ***-four hours later,mice were euthanized,the lungs were immediately removed,and biochemical and histological studies were *** A single dose of CP markedly altered the levels of several biomarkers associated with oxidative stress in lung *** with Zataria multiflora significantly inhibited the elevation of lipid peroxidation level and the depletion in glutathione content,and superoxide dismutase and catalase activities induced by CP in *** addition,Zataria multiflora effectively alleviated CP-induced histopathological abnormality and pulmonary damages in mice lung *** The results reveal that Zataria multiflora protects lung tissues from CP-induced toxicity and suggest a role for oxidative stress in the pathogenesis of lung toxicity produced by CP in *** Zataria multiflora has been extensively used as an additive agent and is regarded as safe,it may be used concomitantly as a good supplement for reducing organ toxicity in patients undergoing chemotherapy,besides their consolidated ethnopharmacological uses.

关键词： pulmonoprotective Zataria multiflora cyclophosphamide lung toxicity oxidative stress antioxidant activity

Measuring Electrospun Nanofibre Diameter： a Novel Approach

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Chinese Physics Letters 2008年第8期25卷 3071-3074页

作者： M. Ziabari V. Mottaghitalab S. T. McGovern A. K. haghi Textile Department University of Guilan PO Box 3756 Rasht Iran Intelligent Polymer Research Institute University of Wollongong Wollongong Australia

A new method based on image analysis for electrospun nanofibre diameter measurement is presented. First, the SEM micrograph of the nanofibre web obtained by electrospinning process is converted to binary image using local thresholding method. In the next step, skeleton and distance transformed image are generated. Then, the intersection points which bring about untrue measurements are identified and removed from the skeleton. Finally, the resulting skeleton and distance transformed image are used to determine fibre diameter. The method is evaluated by a simulated image with known characteristics generated by ？-randomness procedure. The results indicate that this approach is successful in making fast, accurate automated measurements of electrospun fibre diameters.

关键词： NANOFIBERS SIMULATION NONWOVENS

On the origin of the high tensile strength and ductility of additively manufactured 316L stainless steel: Multiscale investigation

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Journal of Materials Science & Technology 2020年第6期41卷 209-218页

作者： Bassem Barkia Pascal Aubry Paul haghi-Ashtiani Thierry Auger Lionel Gosmain Frédéric Schuster Hicham Maskrot DEN-Service d’Etudes Analytiques et de Réactivitédes Surfaces CEAUniversitéParis-Saclay91191France Laboratoire de Mécanique des Sols Structures et MatériauxCentralesupélecUMR CNRS 8579UniversitéParis-Saclay92295France Arts et Métiers ParisTech PIMMUMR CNRS 800675013 ParisFrance CEA Cross-Cutting Program on Materials and Processes Skills 91191Gif-sur-YvetteFrance

We report that 316L austenitic stainless steel fabricated by direct laser deposition(DLD),an additive manufacturing(AM)process,have a higher yield strength than that of conventional 316L while keeping high *** interestingly,no clear anisotropy in tensile properties was observed between the building and the scanning direction of the 3D printed *** examination of the as-built parts shows a heterogeneous solidification cellular *** electron microscopy observations coupled with Energy Dispersive X-ray Spectrometry(EDS)reveal the presence of chemical micro-segregation correlated with high dislocation density at cell boundaries as well as the in-situ formation of well-dispersed oxides and transition-metal-rich *** hierarchical heterogeneous microstructure in the AM parts induces excellent strength of the 316L stainless steel while the low staking fault energy of the as-built 316L promotes the occurrence of abundant deformation twinning,in the origin of the high ductility of the AM *** additional post-process treatments,the AM 316L proves that it can be used as a structural material or component for repair in mechanical construction.

关键词： Additive manufacturing Austenitic stainless steel Dislocation structure Twinning Mechanical behavior Anisotropy

Laguerre reproducing kernel method in Hilbert spaces for unsteady stagnation point ow over a stretching/shrinking sheet

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Applied Mathematics(A Journal of Chinese Universities) 2021年第3期36卷 354-369页

作者： M.R.Foroutan A.S.Gholizadeh Sh.Najafzadeh R.H.haghi Department of Mathematics Payame Noor UniversityP O Box 19395-3697TehranIran

This paper investigates the nonlinear boundary value problem resulting from the exact reduction of the Navier-Stokes equations for unsteady magnetohydrodynamic boundary layer flow over the stretching/shrinking permeable sheet submerged in a moving *** solve this equation,a numerical method is proposed based on a Laguerre functions with reproducing kernel Hilbert space *** the operational matrices of derivative,we reduced the problem to a set of algebraic *** also compare this work with some other numerical results and present a solution that proves to be highly accurate.

关键词： nonlinear boundary value problem Laguerre reproducing kernel method operational matrix of derivative existence and nonexistence of solutions approximate solution

Modelling the probability of presence of Aedes aegypti and Aedes albopictus in Iran until 2070

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Asian Pacific Journal of Tropical Medicine 2023年第1期16卷 16-25页

作者： Mohammad Mehdi Sedaghat Faramarz Bozorg Omid Mohammad Karimi Sajjad haghi Ahmad Ali Hanafi-Bojd Department of Vector Biology&Control School of Public HealthTehran University of Medical SciencesTehranIran Department of GIS Faculty of Geodesy and Geomatics EngineeringK.N.Toosi University of TechnologyTehranIran Zoonoses Research Center Tehran University of Medical SciencesTehranIran

Objective:To determine the suitable ecological habitats of Aedes(Ae.)aegypti and *** in Iran due to climate change by the ***:All data relating to the spatial distribution of *** and *** worldwide,which indicated the geographical coordinates of the collection sites of these mosquitoes,were extracted from online scientific websites and entered into an Excel *** effect of climatic and environmental variables on these mosquitoes was evaluated using the MaxEnt model in the current and future climatic conditions in the 2030s,2050s,and ***:The most suitable areas for the establishment of *** are located in the southern and northern coastal areas of Iran,based on the model *** modelling result for suitable ecological niches of *** shows that in the current climatic conditions,the southern half of Iran from east to west,and parts of the northern coasts are prone to the presence of this *** the future,some regions,such as Gilan and Golestan provinces,will have more potential to exist/establish ***,according to the different climate change scenarios,suitable habitats for this species will gradually change to the northwest and west of the *** temperature of the wettest season of the year(Bio8)and average annual temperature(Bio1)were the most effective factors in predicting the model for *** and ***,***:It is required to focus on entomological studies using different collection methods in the vulnerable areas of *** future modelling results can also be used for long-term planning to prevent the entry and establishment of these invasive Aedes vectors in the country.

关键词： Aedes aegypti Aedes albopictus Dengue fever Chikungunya Ecological Niche Modeling Climate change