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Unconfined compressive strength prediction of soils stabilized using artificial neural networks and support vector machines

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Frontiers of Structural and Civil Engineering 2021年第2期15卷 520-536页

作者： Alireza TABARSA Nima LATIFI abdolreza osouli Younes BAGHERI Depatrment of Civil Engineering Faculty of EngineeringGolestan UniversityGorgan 49138-15759Iran Terr aeon Consultants Inc.NashvilleTN 37211USA Civil Engineering Department Southern Illinois UniversityEdwardsvilleIL 62026-1800USA Faculty of Engineering Mirdamad Institute of Higher EducationGorgan 49166-53989Iran

This study aims to improve the unconfined compressive strength of soils using additives as well as by predicting the strength behavior of stabilized soils using two artificial-intelligence-based *** soils used in this study are stabilized using various combinations of cement,lime,and rice husk *** predict the results of unconfined compressive strength tests conducted on soils,a comprehensive laboratory dataset comprising 137 soil specimens treated with different combinations of cement,lime,and rice husk ash is *** artificial-intelligence-based models including artificial neural networks and support vector machines are used comparatively to predict the strength characteristics of soils treated with cement,lime,and rice husk ash under different *** suggested models predicted the unconfined compressive strength of soils accurately and can be introduced as reliable predictive models in geotechnical *** study demonstrates the better performance of support vector machines in predicting the strength of the investigated soils compared with artificial neural *** type of kernel function used in support vector machine models contributed positively to the performance of the proposed ***,based on sensitivity analysis results,it is discovered that cement and lime contents impose more prominent effects on the unconfined compressive strength values of the investigated soils compared with the other parameters.

关键词： unconfined compressive strength artificial neural network support vector machine predictive models regression

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Modeling and simulation of induction motor drive system to investigate and mitigate of PWM inverter’s adverse effects

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Journal of Harbin Institute of Technology(New Series) 2007年第1期14卷 83-88页

作者： ESMAELI abdolreza 孙力 Dept. of National Radiation Protection Iranian Nuclear Regulatory Authority

Modeling and simulation of induction motor drive system to investigate and mitigate the adverse effects of PWM inverter based on analysis, modeling and simulation are presented. The estimation of conducted disturbances and other adverse effects of PWM inverter by simulation offer a considerable gain from the economic point of view. For an accurate model of the motor drive system including mains, rectifier, inverter, motor and its long cables, the high frequency parasitic current paths are taken into account. The novel model and its parasitic values for three-phase induction motor system are presented. Finally a new solution for suppressing EMI, common mode voltage, leakage current, bearing current and shaft voltages is proposed and the results show the excellent performances of proposed solution including active and passive filters.

关键词： induction motor PWM inverter adverse effects EMC high frequency model

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Conducted EMI Suppression in Plasma Cutting Power Supply

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Plasma Science and Technology 2005年第6期7卷 3170-3173页

作者： abdolreza Esmaeli 孙力赵克 National Radiation Protection Department Iranian Nuclear Regulatory Authority Tehran IranElectrical Engineering and Automation School Harbin Institute of Technology Harbin 150001 China Electrical Engineering and Automation School Harbin Institute of TechnologyHarbin 150001 China

A systematic approach to the design of the conducted electromagnetic interference （EMI） filter of high-density plasma cutting power supply has been developed. Converter components have been accurately modeled, with parasitic elements extracted to reveal their impacts on the EMI noises. Circuit simulations have been used to analyze and minimize the EMI noises. Conducted EMI noise measurement and filter design of this power supply have been achieved which successfully satisfy the FCC class B limits in the frequency range from 150 kHz to 30 MHz. The analyses and experimental results show that the designed filter guarantees that the required attenuation will be achieved.

关键词： conducted electromagnetic interference (EMI) plasma cutting power supply electromagnetic compatibility (EMC) saber designer filter design

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The mathematical weighting of GNSS observations based on different types of receivers/antennas and environmental conditions

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Geodesy and Geodynamics 2023年第5期14卷 521-540页

作者： Kamal Parvazi Saeed Farzaneh abdolreza Safari School of Surveying and Geospatial Engineering College of EngineeringUniversity of TehranNorth Kargar Street***TehranIran

Stochastic models play an important role in achieving high accuracy in positioning,the ideal estimator in the least-squares(LS)can be obtained only by using the suitable stochastic *** study investigates the role of variance component estimation(VCE)in the LS method for Precise Point Positioning(PPP).This estimation is performed by considering the ionospheric-free(IF)functional model for code and the phase observation of Global Positioning System(GPS).The strategy for estimating the accuracy of these observations was evaluated to check the effect of the stochastic model in four modes:a)antenna type,b)receiver type,c)the tropospheric effect,and d)the ionosphere *** results show that using empirical variance for code and phase observations in some cases caused erroneous estimation of unknown components in the PPP *** is because a constant empirical variance may not be suitable for various receivers and antennas under different *** were compared in two cases using the stochastic model of nominal weight and weight estimated by *** position error difference for the east-west,north-south,and height components was 1.5 cm,4 mm,and 1.8 cm,***,weight estimation with LS-VCE can provide more appropriate ***,the convergence time based on four elevation-dependent models was evaluated using nominal weight and LS-VCE *** to the results,the LS-VCE has a higher convergence rate than the nominal *** weight estimation using LS-VCE improves the convergence time in four elevation-dependent models by 11,13,12,and 9 min,respectively.

关键词： Stochastic model Global positioning system Variance component estimation Least-squares Precise point positioning Elevation-dependent model

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TiO2 nanoparticles in aquatic environments:impact on heavy metals distribution in sediments and overlying water

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Acta Geochimica 2022年第6期41卷 968-981页

作者： Ali Marefat abdolreza Karbassi Behzad Aghabarari School of Environment College of EngineeringUniversity of TehranTehranIran Research Department of Nano-technology and Advanced Materials TehranIran

The extensive application of TiO_(2)nanoparticles(NPs)highlights the importance of investigating their influence on aquatic *** this work,the effect of TiO_(2)NPs on heavy metals speciation was studied on a lab *** this goal,a series of aquaria containing water,sediment,and TiO_(2)NPs with various concentrations were set *** study results revealed that TiO_(2)NPs caused(copper)Cu,(mercury)Hg,(titanium)Ti,and(zinc)Zn to be adsorbed by sediments in the forms of exchangeable and Fe-Mn *** to measurements,30μg/L of TiO_(2)NPs made Cu,Hg,Ti and Zn concentration in the water column decreased from 33,1.14,20,and 32 to 4,0.58,3,and 22.3μg/L,***(Mn)was also adsorbed by sediment,and in all experiments,its concentration in the water column reduced from 44 to about 20μg/*** to the photocatalytic capacity of TiO_(2)NPs,arsenic(As)concentration in the water column increased from 0 to 8.7μg/L with the introduction of30μg/L of TiO_(2)*** sequential extraction results showed that in all experiments,concentrations of lead(Pb),nickel(Ni),and cobalt(Co)remained constant in different chemical species of sediment,which meant conservative behavior of them in presence of TiO_(2)*** addition,a remarkable change was observed in water quality parameters such as ORP,TDS,TOC,BOD,NO3’and PO_(4)after the introduction of TiO_(2)NPs to *** reason behind these changes could be related to the decomposition of sediment organic content by TiO_(2)NPs.

关键词： TiO2 nanoparticles Heavy metal speciation Redox potential Chemical extraction Cluster analysis

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Heavy metals in sediments and their bioaccumulation in Phragmites australis in the Anzali wetland of Iran

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Chinese Journal of Oceanology and Limnology 2016年第4期34卷 810-820页

作者： Marjan ESMAEILZADEH abdolreza KARBASSI Faramarz MOATTAR Department of Environmental Science Faculty of Environment and Energy Tehran Science and Research Branch Islamic Azad University Department of Environmental Engineering Graduate Faculty of Environment University of Tehran

Accumulation of metals in both sediments and Phragmites australis organs was studied. Samples were collected from seven stations located in Anzali wetland, Iran. The samples were analyzed by inductively coupled plasma mass spectrometry(ICP-MS). The results showed that concentration of the studied metals(except As and Cd) were higher in sediments than in *** organs. Metal accumulation was found to be signifi cantly(P <0.05) higher in roots than in above-ground organs of ***. The bioaccumulation factor(BAF) and the transfer factor(TF) also verifi ed the highest rate of metal accumulation in roots and their reduced mobility from roots to the above-ground organs. Pearson correlation coeffi cient showed signifi cant relationships between metal concentrations in sediments and those in plant organs. It should be pointed out that sediment and plant samples exhibited higher metal concentrations in eastern and central parts than in western and southern parts of the wetland. The mean concentrations of all studied elements(except for Fe, V and Al) were higher in these sediment samples than in the Earth's crust and shale. High accumulation of metals in P. australis organs(roots and shoots) is indicative of their high bioavailability in sediments of the wetland. The correlation between metal concentrations in sediments and in P. australis indicates that plant organs are good bioindicators of metal pollution in sediments of Anzali wetland.

关键词： transfer factor bioaccumulation factor aquatic plant phytotoxic level trace elements

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Folded Radiolarite Unit as a Kinematic Indicator of the Zagros Collision Processes, Southwestern Iran

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Journal of Earth Science 2018年第1期29卷 210-222页

作者： abdolreza Partabian Ahmad Nourbakhsh Khalil Sarkarinejad Department of Geology College of Science University of Sistan and Baluchestan Department of Earth Sciences College of Sciences Shiraz University

Radiolarites have an important role in the reconstruction of the paleogeography, bathymetry and their coexistence with ophiolites gives an opportunity to determine the tectonic his- tory of collisional zones. The radiolarite units of the southwestern Neyriz are part of the Zagros ac- cretionary prism and positioned beneath the thick bedded carbonate sediments of Tarbur Forma- tion. The existing various structural elements within this unit give a unique fortunate for investiga- tion on the deformation history and studying of the kinematics of the Zagros collision zone. The nu- merous evidence show that this unit has experienced different deformation conditions during ongo- ing evolution, including ductile, brittle-ductile and brittle deformation conditions. The main strike of E-W for axial planes of folds, eastward trend and plunge of fold axes, boudins＇ neck axes and Type III of the fold interference patterns are indicators of formation and evolution of folds during tran- spressional deformation. Structural evolution of the study area has been affected by an NE-dipping subduction zone of Neo-Tethyan oceanic lithosphere below the Iranian microcontinents. These structural elements suggest that high mechanical anisotropy and two successive generations of fold- ing simultaneously with thrusting and extrusion of this unit had led to formation and evolution of this highly asymmetrical folded unit on top of the subducted oceanic crust.

关键词： Iran Zagros suture zone kinematic indicator transpression deformation conditions.

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Assessment of metal pollution in the Anzali Wetland sediments using chemical partitioning method and pollution indices

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Acta Oceanologica Sinica 2016年第10期35卷 28-36页

作者： ESMAEILZADEH Marjan KARBASSI abdolreza MOATTAR Faramarz Department of Environmental Science Faculty of Environment and Energy Tehran Science and Research BranchIslamic Azad University Department of Environmental Engineering Graduate Faculty of Environment University of Tehran

Metal pollution in aquatic ecosystems is of immense importance. Under various environment circumstances, the metal contents of sediments can enter into the overlying water body leading to severe toxicity. This study aims to determine metal concentrations in sediments of Anzali International Wetland in Iran. Chemical partitioning method is used to determine the portion of anthropogenic pollution and the mobility potential of each metal. The intensity of metal pollution in sediments of the wetland is assessed using three reliable indices. The results of chemical partitioning reveal that cadmium bear the highest risk of being released into the aquatic environment and high amount of manganese in sulfide bond phase implies the initiation of redox state in aquatic environment of the Anzali Wetland. The results of chemical partitioning studies show that Pb, Cd, Mn and As have the highest anthropogenic portion. Cluster analysis also confirms the results of chemical partitioning and indicates that the mentioned metals can be originated from anthropogenic sources. Sediment pollution indices, including, Igeo,IPOLL, and m-ERM-Q reveal that metals are in the range of low to moderate pollution and also show that the highest metal pollution is in the eastern and central parts of the wetland. This can be ascribed to rivers which are the recipient of industrial, agricultural and municipal wastewaters and flow into these parts of the wetland.

关键词： pollution environment sediment metal geochemistry

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The Maastrichtian-Danian in the SW Zagros Fold-Thrust Belt(S. Iran):An Integration of Planktonic Foraminiferal Biostratigraphy and Gamma-Ray Spectrometry

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Acta Geologica Sinica(English Edition) 2020年第5期94卷 1339-1363页

作者： abdolreza MOGHADDASI Hossein VAZIRI-MOGHADDAM Ali SEYRAFIAN Department of Geology Faculty of SciencesUniversity of IsfahanIsfahanIran

In this study, the Maastrichtian-Danian boundary was measured and sampled in two stratigraphic sections, the north and south flanks of the Dehnow anticline in Coastal Fars, Southern Iran. This boundary was also investigated in the drilled exploratory well-1 in the same region. The lithology of the Maastrichtian-Danian deposits consists of glauconitic, phosphatic argillaceous limestones and marlstones. 30 genera and 77 species of planktonic foraminifera have been determined. The recognized biozones are the Gansserina gansseri Interval Zone, and the Contusotruncana contusa Interval Zone, which indicates latest Campanian to middle Maastrichtian age for the upper part of the Gurpi Formation. In addition, the Eoglobigerina edita(P1) Partial Range Zone, Praemurica uncinata(P2) Lowest Occurrence Zone, Morozovella angulata(P3) Lowest Occurrence Zone and Globanomalina psudomenardii(P4) Taxon Range Zone represent a Danian to Thanetian age for the lower part of the Pabdeh Formation. From the absence of the Abathomphalus mayaroensis Interval Zone, Pseudoguembelina hariaensis Interval Zone, Pseudotextularia elegans Interval Zone, Plummerita hantkeninoides Interval Zone, Guembelitria cretacea(P0) Partial Range Zone and Parvularugoglobigerina eugubina(Pα) Total Range Zone, it can be deduced that there is a paraconformity across the Maastrichtian–Danian boundary in the studied area, this hiatus encompassing the late Maastrichtian and the earliest Danian. Danian deposits from the study area contain reworked glauconitized macrofossils, planktonic and benthic foraminifera of the Cretaceous. The obtained surface gamma-ray spectrometry logs resemble the exploratory well-1 gamma-ray wireline log.

关键词： biostratigraphy planktonic foraminifera gamma-ray spectrometry Maastrichtian-Danian Zagros Iran

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Probabilistic safety assessment of self-centering steel braced frame

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Frontiers of Structural and Civil Engineering 2018年第1期12卷 163-182页

作者： Navid RAHGOZAR Nima RAHGOZAR abdolreza S. MOGHADAM Department of Structural Engineering Science and Research Branch Islamic Azad University Tehran Iran Structural Engineering Research Center International Institute of Earthquake Engineering and Seismology (IIEES) Tehran Iran

The main drawback of conventional braced frames is implicitly accepting structural damage under the design earthquake load, which leads to considerable economic losses. Controlled rocking self-centering system as a modem low-damage system is capable of minimizing the drawbacks of conventional braced frames. This paper quantifies main limit states and investigates the seismic performance of self-centering braced frame using a Probabilistic Safety Assessment procedure. Margin of safety, confidence level, and mean annual frequency of the self-centering archetypes for their main limit states, including PT yield, fuse fracture, and global collapse, are established and are compared with their acceptance criteria. Considering incorporating aleatory examined. Results of the investigation indicate that the provide the adequate margin of safety against exceeding and epistemic uncertainties, the efficiency of the system is design of low- and mid-rise self-centering archetypes could the undesirable limit-states.

关键词： self-centering steel braced frame mean annual frequency safety assessment confidence level margin of safety

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