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Homomorphisms in Quasi-Banach Algebras Associated with a Pexiderized Cauchy-Jensen Functional Equation

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Acta Mathematica Sinica,English Series 2009年第9期25卷 1529-1542页

作者： abbas NAJATI Department of Mathematics Faculty of Sciences University of Mohaghegh Ardabili

In this paper, we prove the generalized Hyers-Ulam stability of homomorphisms in quasi- Banach algebras associated with the following Pexiderized Jensen functional equation f（x＋y/2＋z）-g（x-y/2＋z）=h（y）.This is applied to investigating homomorphisms between quasi-Banach algebras. The concept of the generalized Hyers-Ulam stability originated from Rassias＇ stability theorem that appeared in his paper： On the stability of the linear mapping in Banach spaces, Proc. Amer. Math. Soc., 72, 297-300 （1978）.

关键词： Cauchy additive mapping Jensen additive mapping homomorphisms in quasi-Banach algebras generalized Hyers-Ulam stability p-Banach algebra

Assessing the seismic behavior of steel moment frames equipped by elliptical brace through incremental dynamic analysis(IDA)

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Earthquake Engineering and Engineering Vibration 2020年第2期19卷 435-449页

作者： Ghasemi Jouneghani abbas Haghollahi Department of Civil Engineering Shahid Rajaee Teacher Training UniversityTehranIran

Incremental dynamic analysis and nonlinear static pushover analysis are carried out on a performance-based design to determine the seismic demands and capacities of an elliptic braced moment resisting frame(ELBRF).The objective is to assess ductility,overstrength and response modification factors in a modern steel-braced structural system based on incremental dynamic *** integrated system is connected to a beam and column with an appropriate length while providing enough architectural space to allow for an opening without having the common problems associated with architectural spaces in braced *** different classes of buildings are considered on soil type *** dynamic analysis,nonlinear static pushover analysis and incremental nonlinear dynamic analysis related to 12 records from past earthquakes are carried out using OpenSees *** factors of ductility,overstrength and response modification are calculated for this *** values of 9.5 and 6.5 are found and suggested only for the response modification factor for ELBRF systems in allowable stress and ultimate limit state methods,*** fragility curves are plotted for the first time for this type of bracing,which contributes to the assessment of building seismic damage.

关键词： elliptic brace response modification factor overstrength factor ductility factor incremental dynamic analysis,fragility curve

Non-Uniformity of Heavy-Ion Beam Irradiation on a Direct-Driven Pellet in Inertial Confinement Fusion

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Plasma Science and Technology 2011年第1期13卷 44-49页

作者： Leila GHOLAMZADEH abbas GHASEMIZAD Physics Department Faculty of ScienceUniversity of Guilan

Heavy-ion-driven fusion （HIF） is a scheme to achieve inertial confinement fusion （ICF）. Investigation of the non-uniformity of heavy-ion beam （HIB） irradiation is one of the key issues for ICF driven by powerful heavy-ion beams. Ions in HIB impinge on the pellet surface and deposit their energy in a relatively deep and wide area. Therefore, the non-uniformity of HIB irradiation should be evaluated in the volume of the deposition area in the absorber layer. By using the OK1 code with some corrections, the non-uniformity of heavy-ion beam irradiation for the different ion beams on two kinds of targets were evaluated in 12-beam, 20-beam, 60-beam and 120-beam irradiation schemes. The root-mean-square （RMS） non-uniformity value becomes aRMS = 8.39% in an aluminum mono-layer pellet structure and aRMS = 6.53% in a lead-aluminum layer target for the 12-uranium-beam system. The RMS non-uniformity for the lead-aluminum layer target was lower than that for the mono-layer target. The RMS and peak-to-valley （PTV） non-uniformities are reduced with the increase in beam number, and low at the Bragg peak layer.

关键词： heavy ion beam deposition energy irradiation non-uniformity inertial con- finement fusion Bragg peak layer

Macro- and micromechanical evaluation of cyclic simple shear test by discrete element method

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Particuology 2017年第2期15卷 129-139页

作者： Mozhgan Asadzadeh abbas Soroush Department of Civil and Environmental Engineering Amirkabir University of Technology Tehran Iran

Direct simple shear tests are considered to be simple laboratory tests that are capable of imposing a cyclic loading that is analogous to that induced by earthquakes. A realistic evaluation of the test results demands a profound micromechanical investigation of specimens. Three-dimensional discrete element method models of a stacked-ring simple shear test were constructed, in which monotonic and cyclic loadings were applied under constant-volume conditions, and good agreement between the monotonic and cyclic macromechanical behaviors was noted. Micromechanical properties of specimens that were subjected to a cyclic loading are discussed in terms of lateral and intermediate principal stress development, fabric anisotropy, and principal stress rotation. The stress and strain states inside the specimen were investigated and it was shown that despite the uniform stress distribution inside the specimen, the volumetric strain distributes non-uniformly during loading and the non-uniformity grows with cycling, which leads to localized zones of dilative and contractive behavior.

关键词： Discrete element method Direct shear test Simple shear test Cyclic loading

Prediction of bed load sediments using different artificial neural network models

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Frontiers of Structural and Civil Engineering 2020年第2期14卷 374-386页

作者： Reza ASHEGHI Seyed abbas HOSSEINI Department of Civil Engineering Science and Research BranchIslamic Azad UniversityTehranIran

Modeling and prediction of bed loads is an important but difficult issue in river *** introduced empirical equations due to restricted applicability even in similar conditions provide different accuracies with each other and measured *** this paper,three different artificial neural networks(ANNs)including multilayer percepterons,radial based function(RBF),and generalized feed forward neural network using five dominant parameters of bed load transport formulas for the Main Fork Red River in Idaho-USA were *** optimum models were found through 102 data sets of flow discharge,flow velocity,water surface slopes,flow depth,and mean grain *** deficiency of empirical equations for this river by conducted comparison between measured and predicted values was approved where the ANN models presented more consistence and closer estimation to observed *** coefficient of determination between measured and predicted values for empirical equations varied from 0.10 to 0.21 against the 0.93 to 0.98 in ANN *** accuracy performance of all models was evaluated and interpreted using different statistical error criteria,analytical graphs and confusion *** the ANN models predicted compatible outputs but the RBF with 79%correct classification rate corresponding to 0.191 nctwork error was outperform than others.

关键词： bed load prediction artificial neural network modeling empirical equations

A rapid and efficient method for the synthesis of 14H-dibenzo[α.j]xanthenes,aryl-5H-dibenzo[b.i]xanthene-5,7,12,14-(13H)-tetraone and 1,8-dioxooctahydroxanthenes by acidic ionic liquid

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Chinese Chemical Letters 2010年第7期21卷 761-764页

作者： abbas Rahmati Department of Chemistry University of IsfahanP.O.Box 81746-7344IsfahanIran

Various xanthenes have been synthesized by the condensation ofβ-naphthol,2-hydroxynaphthalene-1,4-dione or dimedone with various aldehydes in the presence of trifluoroacetic acid as catalyst in 1,1,3,3-N,N,N′,N′-te... 详细信息

关键词： Ionic liquid 14H-Dibenzo[α.j]xanthenes β-Naphthol 2-Hydroxynaphthalene-1 4-dione Dimedone

Use of probabilistic and deterministic measures to identify unfavorable earthquake records

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Journal of Zhejiang University-Science A(Applied Physics & Engineering) 2009年第5期10卷 619-634页

作者： abbas MOUSTAFA Izuru TAKEWAKI Department of Urban and Environmental Engineering Graduate School of Engineering Kyoto UniversityNishikyo-ku 615-8540 Japan Department of Civil Engineering School of Engineering Minia UniversityMinia 61111 Egypt

This study introduces measures to identify resonant (concentration of energy in a single or a few frequencies) or unfavorable earthquake ground motions. Probabilistic measures based on the entropy rate and the geometric properties of the power spectral density function (PSDF) of the ground acceleration are developed first. Subsequently, deterministic measures for the frequency content of the ground acceleration are also developed. These measures are then used for identifying resonance and criticality in stochastic earthquake models and 110 acceleration records measured at rock, stiff, medium and soft soil sites. The unfavorable earthquake record for a given structure is defined as the record having a narrow frequency content and dominant frequency close to the structure fundamental natural frequency. Accordingly, the measures developed in this study may provide a basis for selecting records that are capable of producing the highest structural response. Numerical verifications are provided on damage caused to structures by identified resonant records.

关键词： Entropy rate Dispersion index Power spectral density function (PSDF) Frequency content Unfavorable groundmotion Resonant acceleration Critical accelerogram Energy Damage index

Simultaneous removal of copper and zinc ions by low cost natural snail shell/hydroxyapatite/chitosan composite

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Chinese Journal of Chemical Engineering 2021年第5期34卷 221-230页

作者： abbas Bambaeero Reza Bazargan-Lari Department of Materials Science&Engineering Marvdasht BranchIslamic Azad UniversityMarvdashtIran

In this work,the snail shell/hydroxyapatite/chitosan composite was prepared as *** adsorption potential of the composite was studied for simultaneous sorption behavior of Zn(Ⅱ)and Cu(Ⅱ)ions in a batch *** and hydroxyapatite(HAP)were extracted from shrimp shell and bone ash,respectively,so this is a low cost natural *** prepare the composite,chitosan was dissolved in acetic acid,then HAP and snail shell powders were added to the chitosan *** morphology and characterization of the composite was studied by SEM and EDX *** adsorption was used to measure the amount of the *** parameters were optimized with Design Expert Software and five parameters such as the concentration of ions,pH,adsorbent amount and contact time were studied at room *** value for the parameters of Zn(Ⅱ)and Cu(Ⅱ)concentrations,pH,adsorbent dose,and contact time were 3.01 mg·L^(-1),5.5,0.02 g and 95 min,*** adsorption isotherms for Zn(Ⅱ)and Cu(Ⅱ)showed Langmuir and Tempkin,*** and equilibrium studies showed the experimental data of Zn(Ⅱ)and Cu(Ⅱ)ions were best described by the pseudo-second-order *** on thermodynamic show the adsorption process were physical and spontaneous.

关键词： Hydroxyapatite Chitosan Composite Adsorbent

Effects of rotational components of earthquake on seismic response of arch concrete dams

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Earthquake Engineering and Engineering Vibration 2020年第2期19卷 349-362页

作者： Amir Javad Moradloo abbas Naiji Department of Civil Engineering School of EngineeringUniversity of ZanjanZanjan 38791-45371Iran

The present study deals with dynamic analysis of arch concrete dams,taking rotational components of earthquakes into account.A modified methodology was used to evaluate the rotational components of the *** translational components of the earthquake have been used in to obtain the rotational components of the earthquake,based on the intersecting isotropic elastic wave *** rotational components of Taft,Tabas and San-Fernando earthquakes are evaluated based on the translational components of the earthquakes and considering frequency dependencies of incident angle and wave ***,dynamic analyses of Morrow Point Dam are presented to evaluate the effects of combined translational and rotational components on the seismic response of the *** conditions of reservoirs,including full and empty state,are considered in the ***–structure interaction was completely taken into *** was realized that incorporating rotational components increased the maximum compressive and tensile stresses in both empty and full reservoir *** of maximum tensile stresses is very sensitive to the rotational components of the ***,it can be concluded that the segregated effect of the rocking component on the response of concrete dams is more effective than the sole effect of the torsional component.

关键词： rotational components earthquake arch concrete dam seismic analysis fluid-structure interaction