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Journal of Zhejiang University-Science C(Computers and Electronics) 2010年第8期11卷 645-653页

作者： alireza REZAZADEH Mostafa SEDIGHIZADEH Ahmad HASANINIA Faculty of Electrical and Computer Engineering Shahid Beheshti University Faculty of Engineering and Technology Imam Khomeini International University

This paper develops a modified optimization procedure for coordination of a power system stabilizer (PSS) and a thyristor controlled series compensator (TCSC) controller to enhance the power system small signal *** new approach employs eigenvalue-based and time-domain simulation based objective functions simultaneously to improve the optimization convergence rate.A modified particle swarm optimization (MPSO) algorithm is used as the optimization *** results of simulations and eigenvalue analysis for a single machine infinite bus (SMIB) system equipped with the proposed PSS and TCSC controllers confirm that the new approach is effective in enhancing the system stability.

关键词： Coordination Particle swarm optimization (PSO) Power system stabilizer (PSS) Small signal stability Thyristor controlled series compensator (TCSC) controller

Circulation cells topology and their effect on migration pattern of different multi-bend meandering rivers

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International Journal of Sediment Research 2020年第6期35卷 636-650页

作者： Fariba Sadat Esfahani alireza Keshavarzi Water Engineering Department Shiraz University Centre for Infrastructure Engineering School of EngineeringWestern Sydney University

In meandering rivers,a cross-stream flow,referred to as a secondary current,has important effects on broad spectra of hydraulic/environmental characteristics,running the gamut from river hydrodynamics and geomorphology to stream *** transport equation for vorticity and kinetic energy transfer should be analyzed to specify terms involved in generation of secondary ***,there is limited research on scrutinizing these terms in meandering *** the other hand,while rivers are mostly multi-bend,previous studies have been limited to single *** the current paper,three physical multi-bend channels representing a strongly curved bend,a mild bend and an elongated symmetrical meander loop are designed in order to unravel mechanisms responsible for forming circulation cells in cross *** are carried out in the middle bend of these *** turbulence anisotropy considerably strengthens almost all near bank ***,contrary to single sharp bends,multi bend effects hinder the transfer of the kinetic energy in both directions in the entrance section of the strongly curved bend.

关键词： Circulation cells Multi bend channels Vorticity equation Kinetic energy transfer

Investigation of Binding Energy and Potential in Mesons

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Communications in Theoretical Physics 2019年第7期71卷 813-818页

作者： alireza Khalaghi Majid Monemzadeh Narges Tazimi Department of Physics University of Kashan

Truly by looking through the analytical model of constituent quarks and further the importance of the effects of relativity on quark dynamics in studying the interior structure of mesons,in this research we have strived to have a much more precise modeling for quark interior *** by observing the constituent model of quarks,at first we consider the mesons as two-body system,then we place the considered calculated Potential,which is a function of location and spin,in Schr¨odinger’s *** we will solve the mentioned equation in analytical *** on this solution,we will import the spin and isospin interactions as perturbation in our problem,and finally by using these solutions we can obtain both binding energy and wave function for bound state and excited states of ***,by applying these calculations in the next and last step we will compare our data about meson’s binding energy and masses with others results.

关键词： mesons binding energy spin and isospin interactions Schrodinger's equation exact solution

Experimental and modelling study of the solubility of CO_2 in various CaCl_2 solutions at different temperatures and pressures

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Petroleum Science 2014年第4期11卷 569-577页

作者： alireza Bastami Mohammad Allahgholi Peyman Pourafshary Institute of Petroleum Engineering School of Chemical Engineering Faculty of Engineering University of Tehran Institute of Petroleum Engineering School of Chemical Engineering Faculty of Engineering University of Tehran (Now with Department of Petroleum and Chemical Engineering Sultan Qaboos University)

Study of the thermodynamic behaviour of CaCl2-H2O-CO2 systems is important in different scientific areas in the chemical and petroleum engineering fields. For example, a system including salt- H20-CO2 is a common system in CO2 geological storage. During carbonate matrix acidizing, this mixture also appears as the spent acid. Hence, study of the behaviour of this system and the solubility of CO2 in CaCl2 brine in different thermodynamic conditions is critical. In this study, CO2 solubility in 0, 1.90 and 4.80 mol/L CaCl2 solutions at 328.15 to 375.15 K and 68.9 to 206.8 bar were measured. These values are normal for oil reservoirs. A popular thermodynamic model is available in the literature for estimating the CO2 solubility in pure water and NaC1 solutions. In this paper, the available model was modified by experimental work to be applicable for CaCl2 as well. Based on the measured data, the component interaction parameters in the base model were adjusted for a CaCl2-H2O-CO2 system. The developed model could predict CO2 solubility in different conditions with remarkable accuracy, particularly for high concentration solutions and at high pressures. This improvement is up to 65% better than in the base model. This model can be used in Darcy scale models for predicting wormhole propagation during carbonate matrix acidizing.

关键词： Solubility of CO2-CaCl2 carbonate acidizing spent acid wormhole propagation modelling,solubility measurement

Solving Multi-period Interdiction via Generalized Bender's Decomposition

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Acta Mathematicae Applicatae Sinica 2017年第3期33卷 633-644页

作者： Maryam SOLEIMANI-ALYAR alireza GHAFFARI-HADIGHEH Department of Applied Mathematics Azarbaijan Shahid Madani UniversityTabrizIran

This paper considers a novel formulation of the multi-period network interdiction problem. In this model, delivery of the maximum flow as well as the act of interdiction happens over several periods, while the budget of resource for interdiction is limit. It is assumed that when an edge is interdicted in a period, the evader considers a rate of risk of detection at consequent periods. Application of the generalized Benders decomposition algorithm considers solving the resulting mixed-integer nonlinear programming problem. Computational experiences denote reasonable consistency with expectations.

关键词： Bi-level programming network interdiction mixed-integer nonlinear programming generalized benders decomposition

A narrative overview of utilizing biomaterials to recapitulate the salient regenerative features of dental-derived mesenchymal stem cells

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International Journal of Oral Science 2021年第2期13卷 117-128页

作者： Sevda Pouraghaei Sevari Sahar Ansari alireza Moshaverinia Weintraub Center for Reconstructive Biotechnology Division of Advanced ProsthodonticsSchool of DentistryUniversity of CaliforniaLos AngelesLos AngelesCAUSA California NanoSystems Institute University of CaliforniaLos AngelesLos AngelesCAUSA

Tissue engineering approaches have emerged recently to circumvent many limitations associated with current clinical *** elegant approach utilizes a natural/synthetic biomaterial with optimized physiomechanical properties to serve as a vehicle for delivery of exogenous stem cells and bioactive factors or induce local recruitment of endogenous cells for in situ tissue *** by the natural microenvironment,biomaterials could act as a biomimetic three-dimensional(3D)structure to help the cells establish their natural *** a strategy should not only employ a biocompatible biomaterial to induce new tissue formation but also benefit from an easily accessible and abundant source of stem cells with potent tissue regenerative *** human teeth and oral cavity harbor various populations of mesenchymal stem cells(MSCs)with self-renewing and multilineage differentiation *** the current review article,we seek to highlight recent progress and future opportunities in dental MSC-mediated therapeutic strategies for tissue regeneration using two possible approaches,cell transplantation and cell ***,this paper develops a general picture of current innovative strategies to employ dental-derived MSCs combined with biomaterials and bioactive factors for regenerating the lost or defective tissues and offers information regarding the available scientific data and possible applications.

关键词： biomaterials utilizing utilize

An analytical model for estimating rock strength parameters from small-scale drilling data

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Journal of Rock Mechanics and Geotechnical Engineering 2019年第1期11卷 135-145页

作者： Sajjad Kalantari alireza Baghbanan Hamid Hashemalhosseini Department of Mining Engineering Isfahan University of Technology

The small-scale drilling technique can be a fast and reliable method to estimate rock strength parameters. It needs to link the operational drilling parameters and strength properties of rock. The parameters such as bit geometry, bit movement, contact frictions and crushed zone affect the estimated *** analytical model considering operational drilling data and effective parameters can be used for these purposes. In this research, an analytical model was developed based on limit equilibrium of forces in a Tshaped drag bit considering the effective parameters such as bit geometry, crushed zone and contact frictions in drilling process. Based on the model, a method was used to estimate rock strength parameters such as cohesion, internal friction angle and uniaxial compressive strength of different rock types from operational drilling data. Some drilling tests were conducted by a portable and powerful drilling machine which was developed for this work. The obtained results for strength properties of different rock types from the drilling experiments based on the proposed model are in good agreement with the results of standard tests. Experimental results show that the contact friction between the cutting face and rock is close to that between bit end wearing face and rock due to the same bit material. In this case,the strength parameters, especially internal friction angle and cohesion, are estimated only by using a blunt bit drilling data and the bit bluntness does not affect the estimated results.

关键词： Analytical model Rock strength parameters Small-scale drilling data

Fabrication and Characterization of Poly Lactic Acid Scaffolds by Fused Deposition Modeling for Bone Tissue Engineering

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Journal of Wuhan University of Technology(Materials Science) 2020年第1期35卷 248-251页

作者： Mohammad Khodaei Kamran Amini alireza Valanezhad Department of Materials Science and Engineering Golpayegan University of TechnologyGolpayeganIran Department of Materials Engineering Tiran BranchIslamic Azad UniversityIsfahanIran Center for Advanced Engineering Research Majlesi BranchIslamic Azad UniversityIsfahanIran Department of Dental and Biomedical Materials Science Nagasaki UniversityNagasakiJapan

Three-dimensional porous poly-lactic acid(PLA) scaffold was fabricated using fused deposition modeling(FDM) method including 30%, 50% and 70% nominal porosity. Study of phases in initial polymeric material and printed scaffolds was done by X-ray diffraction(XRD), and no significant phase difference was observed due to the manufacturing process, and the poly-lactic acid retains its crystalline properties. The results of the mechanical properties evaluation by the compression test show that the mechanical properties of the scaffold have decreased significantly with increasing the porosity of scaffold. The microstructure of scaffolds were studied by scanning electron microscope(SEM), showing that the pores had a regular arrangement and their morphology changed with porosity change. The mechanical properties of the poly-lactic acid scaffolds printed using fused deposition modeling, can be adapted to the surrounding tissue, by porosity change.

关键词： 3D porous scaffold fused deposition modeling poly-lactic acid biodegradable polymer

Experimental investigation of surfactant adsorption during EOR and soil pollution control processes:Influence of surfactant concentration,water salinity,and clay type

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Petroleum 2024年第3期10卷 527-538页

作者： Arian Pishkoo Behnam Sedaee alireza Bahramian Institute of Petroleum Engineering Chemical Engineering DepartmentCollege of EngineeringUniversity of TehranTehranIran

Surfactant injection is a well-established method of chemical EOR *** adsorption into clay layers can prevent their proper performance and thus reduce the oil recovery *** the other hand,this adsorption property of clay materials can be used to prevent surface and underground water pollution and reduce soil *** this experimental study,the effect of surfactant concentration,electrolyte type(NaCl and MgCl_(2)),and the solution salinity on fluid adsorption into the interlayer space of different clay types(bentonite and kaolinite)was *** analysis was conducted on two relevant clay samples,and immersion and Washburn tests were performed on the desired samples with the Sigma 700 ***,according to the clay type,the most optimal conditions were introduced for the surfactant solution used in the two areas of EOR and environmental processes related to reducing soil *** the EOR processes,the optimal condition for the lowest adsorption amount is C(with 1 CMC concentration and salinity of 100,000 ppm for NaCl salt).This fluid works better in kaolinite *** the environmental field related to the reduction of soil pollution,if the pollutants we are looking for are R and S(with alkyl benzene sulfonic acid as the dominant agent),bentonite has a better performance than kaolinite in terms of adsorption and subsequently pollution *** the polluting fluid contains MgCl_(2) ions in the exact salinity values,the adsorption amount and soil pollution control will be higher for both adsorbent clays than if our fluid has NaCl *** study's findings have a wide range of applications in surfactant flooding designs,surfactant adsorption optimization,and can be generalized to other detergent types.

关键词： EOR Adsorption Clay Bentonite Kaolinite Soil pollution Surfactant Immersion test Washburn test Salinity

EFFECTS OF VISCOUS DISSIPATION ON THERMALLY DEVELOPING FORCED CONVECTION IN A POROUS SATURATED CIRCULAR TUBE WITH AN ISOFLUX WALL

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Applied Mathematics and Mechanics(English Edition) 2006年第5期27卷 617-626页

作者： Kamel Hooman alireza Pourshaghaghy Arash Ejlali Mechanical Engineering Department Bushehr Engineering FacultyPersian Gulf UniversityBushehrIran Mechanical Engineering Department Faculty of EngineeringUniversity of TehranTehranIran Legal and Contracts Petropars Co.TehranIran

The viscous dissipation effect on forced convection in a porous saturated circular tube with an isoflux wall is investigated on the basis of the Brinkman flow model. For the thermally developing region, a numerical study is reported while a perturbation analysis is presented to find expressions for the temperature profile and the Nusselt number for the fully developed region. The fully developed Nusselt number found by numerical solution for the developing region is compared with that of asymptotic analysis and a good degree of agreement is observed.

关键词： forced convection viscous dissipation Brinkman model Darcy number Nusselt number