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Frontiers of Structural and Civil Engineering 2017年第1期11卷 90-99页

作者： Faezehossadat KHADEMI mahmoud akbari Sayed Mohammadmehdi JAMAL Mehdi NIKOO Department of Civil Architectural and Environmental Engineering Illinois Institute of Technology Chicago IL 60616 USA Civil Engineering Department University of Kashan Kashan *** Iran Department of Civil Engineering University of Hormozgan Bandar Abbas 3995 IRAN Ahvaz Branch Islamic Azad University Ahvaz *** IRAN

Evaluating the in situ concrete compressive strength by means of cores cut from hardened concrete is acknowledged as the most ordinary method, however, it is very difficult to predict the compressive strength of concrete since it is affected by many factors such as different mix designs, methods of mixing, curing conditions, compaction, etc. In this paper, considering the experimental results, three different models of multiple linear regression model （MLR）, artificial neural network （ANN）, and adaptive neuro-fuzzy inference system （ANFIS） are established, trained, and tested within the Matlab programming environment for predicting the 28 days compressive strength of concrete with 173 different mix designs. Finally, these three models are compared with each other and resulted in the fact that ANN and ANFIS models enables us to reliably evaluate the compressive strength of concrete with different mix designs, however, multiple linear regression model is not feasible enough in this area because of nonlinear relationship between the concrete mix parameters. Finally, the sensitivity analysis （SA） for two different sets of parameters on the concrete compressive strength prediction are carried out.

关键词： concrete 28 days compressive strength multiple linear regression artificial neural network ANFIS sensitivity analysis (SA)

Determination of water equivalent ratio for some dosimetric materials in proton therapy using MNCPX simulation tool

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Nuclear Science and Techniques 2019年第2期30卷 19-28页

作者： Reza Bagheri Alireza Khorrami Moghaddam Bakhtiar Azadbakht mahmoud Reza akbari Seyed Pezhman Shirmardi Radiation Application Research School Nuclear Science and Technology Research Institute Radiology Department Allied FacultyMazandaran University of Medical Sciences (MazUMS) Department of Medical Engineering Borujerd BranchIslamic Azad University Therapy Level Laboratory Secondary Standard Dosimetry Laboratory

The water equivalent ratio(WER) was calculated for polypropylene(PP), paraffin, polyethylene(PE), polystyrene(PS), polymethyl methacrylate(PMMA), and polycarbonate materials with potential applications in dosimetry and medical physics. This was performed using the Monte Carlo simulation code, MCNPX, at different proton energies. The calculated WER values were compared with National Institute of Standards and Technology(NIST) data, available experimental and analytical results,as well as the FLUKA, SRIM, and SEICS codes. PP and PMMA were associated with the minimum and maximum WER values, respectively. Good agreement was observed between the MCNPX and NIST data. The biggest difference was 0.71% for PS at 150 MeV proton energy. In addition, a relatively large positive correlation between the WER values and the electron density of the dosimetric materials was observed. Finally, it was noted that PE presented the most analogous Depth Dose Characteristics to liquid water.

关键词： Water equivalent ratio Proton therapy Dosimetric materials MCNPX code

Effect of copper slag recovery on hydrometallurgical cut-off grades considering environmental aspects

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Journal of Central South University 2016年第4期23卷 798-807页

作者： AFSHIN akbari ESMAEIL RAHIMI Department of Mining Engineering Islamic Azad University-Central Tehran Branch Department of Mining Engineering Islamic Azad University-South Tehran Branch

Determining the hydrometallurgical cut-off grades specifies the destination of low grade materials and this is subjected to more benefits in mining. Copper production rate is considered as one of the fundamental issues in hydrometallurgical cut-off grades determination. Slags are remarked as one of the main sources of copper. It is not only regarded as a waste but also identified as another resource extracting base metals. Slags are characterized by copper high grade. Thus, slag copper recovery can be led to different cut-off grades and net present value(NPV). The current research scrutinizes the effect of slag recovery by both flotation and hydrometallurgical methods on the hydrometallurgical cut-off grades. For this purpose, the optimum cut-off grade algorithms of hydrometallurgical methods are developed by considering associated environmental parameters, incomes and also the costs. Then, their optimum amounts are calculated with NPV maximization as an objective function. The results indicate that considering slag copper recovery in the hydrometallurgical cut-off grade algorithms reduces the environmental costs caused by slag dumping and leads to more NPV by 9%.

关键词： hydrometallurgy cut-off grades low grade materials waste floatation slag copper recovery environmental parameters slag dumping NPV maximization

Cellulose-based composite scaffolds for bone tissue engineering and localized drug delivery

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Bioactive Materials 2023年第2期20卷 137-163页

作者： Mahsa Janmohammadi Zahra Nazemi Amin Orash mahmoud Salehi Amir Seyfoori Johnson V.John Mohammad Sadegh Nourbakhsh Mohsen akbari Faculty of New Sciences and Technologies Semnan UniversitySemnanP.O.Box:19111-35131Iran Laboratory for Innovations in Micro Engineering(LiME) Department of Mechanical EngineeringUniversity of Victori1Victori1BCV8P 5C2Canada Terasaki Institute for Biomedical Innovations Los AngelesCA90050USA Biotechnology Center Silesian University of TechnologyAkademicka 2A44-100GliwicePoland Faculty of Materials and Metallurgical Engineering Semnan UniversitySemnanP.O.Box:19111-35131Iran

Natural bone constitutes a complex and organized structure of organic and inorganic components with limited ability to regenerate and restore injured tissues,especially in large bone *** improve the reconstruction of the damaged bones,tissue engineering has been introduced as a promising alternative approach to the conventional therapeutic methods including surgical interventions using allograft and autograft *** composite scaffolds consisting of multifunctional biomaterials in combination with the cells and bioactive therapeutic agents have great promise for bone repair and *** and its derivatives are renewable and biodegradable natural polymers that have shown promising potential in bone tissue engineering ***-based scaffolds possess numerous advantages attributed to their excellent properties of non-toxicity,biocompatibility,biodegradability,availability through renewable resources,and the low cost of preparation and ***,cellulose and its derivatives have been extensively used for delivering growth factors and antibiotics directly to the site of the impaired bone tissue to promote tissue *** review focuses on the various classifications of cellulose-based composite scaffolds utilized in localized bone drug delivery systems and bone regeneration,including cellulose-organic composites,cellulose-inorganic composites,cellulose-organic/inorganic *** will also highlight the physicochemical,mechanical,and biological properties of the different cellulose-based scaffolds for bone tissue engineering applications.

关键词： Cellulose Cellulose derivatives Bone tissue engineering Drug delivery system

QUOTIENT SPACE OF LMC-COMPACTIFICATION AS A SPACE OF z-FILTERS

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Acta Mathematica Scientia 2012年第5期32卷 2010-2020页

作者： Mohammad akbari Tootkaboni Department of Mathematics Faculty of ScienceShahed University18151-159TehranIran

The left multiplicative continuous compactification is the universal semigroup compactification of a semitopological *** this paper an internal construction of a quotient space of the left multiplicative continuous co... 详细信息

关键词： LMC-compactification z-filters quotient space

Data driven models for compressive strength prediction of concrete at high temperatures

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Frontiers of Structural and Civil Engineering 2020年第2期14卷 311-321页

作者： Mahmood akbari Vahid JAFARI DELIGANI Department of Civil Engineering Faculty of EngineeringUniversity of KashanKashan ***Iran

The use of data driven models has been shown to be useful for simulating complex engineering processes,when the only information available consists of the data of the *** this study,four data-driven models,namely multiple linear regression,artificial neural network,adaptive neural fuzzy inference system,and K nearest neighbor models based on collection of 207 laboratory tests,are investigated for compressive strength prediction of concrete at high *** addition for each model,two different sets of input variables are examined:a complete set and a parsimonious set of involved *** results obtained are compared with each other and also to the equations of NIST Technical Note standard and demonstrate the suitability of using the data driven models to predict the compressive strength at high *** addition,the results show employing the parsimonious set of input variables is sufficient for the data driven models to make satisfactory results.

关键词： data driven model compressive strength oncrete high temperature

A New Peer-to-Peer Topology for Video Streaming Based on Complex Network Theory

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Journal of Systems Science & Complexity 2015年第1期28卷 16-29页

作者： MARZA Venus DEHGHAN Mehdi akbari Behzad Department of Computer Engineering Science and Research BranchIslamic Azad University Department of Computer Engineering and Information Technology Amirkabir University of Technology Department of Electrical and Computer Engineering Tarbiat Modares University

A new wave of networks labeled Peer-to-Peer(P2P) networks attracts more researchers and rapidly becomes one of the most popular *** order to matching P2 P logical overlay network with physical topology,the position-based topology has been *** proposed topology not only focuses on non-functional characteristics such as scalability,reliability,fault-tolerance,selforganization,decentralization and fairness,but also functional characteristics are addressed as *** experimental results show that the hybrid complex topology achieves better characteristics than other complex networks' models like small-world and scale-free models;since most of the real-life networks are both scale-free and small-world networks,it may perform well in mimicking the ***,it reveals that the authors improve average distance,diameter and clustering coefficient versus Chord and CAN ***,the authors show that the proposed topology is the most robust model,against failures and attacks for nodes and edges,versus small-world and scale-free networks.

关键词： Complex network's metrics complex network models peer-to-peer topology site and bond percolation video streaming.

Gas–liquid flow mass transfer in a T-shape microreactor stimulated with 1.7 MHz ultrasound waves

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Chinese Journal of Chemical Engineering 2017年第9期25卷 1143-1152页

作者： Mona akbari Masoud Rahimi Mahboubeh Faryadi CFD Research Center Chemical Engineering Department Razi University

This paper describes the application of ultrasound waves on hydrodynamics and mass transfer characteristics in the gas–liquid flow in a T-shape microreactor with a diameter of 800 μm. A 1.7 MHz piezoelectric transducer(PZT) was employed to induce the vibration in this microreactor. Liquid side volumetric mass transfer coefficients were measured by physical and chemical methods of CO_2 absorption into water and Na OH solution. The approach of absorption of CO_2 into a 1 mol·L^(-1) Na OH solution was used for analysis of interfacial areas. With the help of a photography system, the fluid flow patterns inside the microreactor were analyzed. The effects of superficial liquid velocity, initial concentration of Na OH, superficial CO_2 gas velocity and length of microreactor on the mass transfer rate were investigated. The comparison between sonicated and plain microreactors(microreactor with and without ultrasound) shows that the ultrasound wave irradiation has a significant effect on kLa and interfacial area at various operational conditions. For the microreactor length of 12 cm, ultrasound waves improved kLa and interfacial area about 21% and 22%, respectively. From this study, it can be concluded that ultrasound wave irradiation in microreactor has a great effect on the mass transfer rate. This study suggests a new enhancement technique to establish high interfacial area and kLa in microreactors.

关键词： Ultrasound waves Microreactor Gas–liquid flow Mass transfer Absorption

Numerical investigation of flow pattern and components of three-dimensional velocity around a submerged T-shaped spur dike in a 90° bend

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Journal of Central South University 2016年第11期23卷 2984-2998页

作者： Mohammad Vaghefi Yaser Safarpoor Maryam akbari Department of Civil Engineering Persian Gulf University

Spur dike is one of the river training structures. This work presented a numerical simulation of flow field and three-dimensional velocity around a T-shaped spur dike located in bend using SSIIM model. The main objective of this work is to investigate the three-dimensional velocities and streamlines at transverse and longitudinal sections and plan views around the T-shaped spur dike in different submergence ratios(0, 5%, 15%, 25% and 50%). It is concluded that by increasing the submergence ratio from 5% to 50%, the maximum of scour is reduced; the maximum of longitudinal velocity increases by 7.7% and occurs at the water surface in spur dike axis. Near the bed, the maximum of vertical velocity occurs at the end of spur wing. By analyzing the streamlines at transverse sections, the followings were deduced for different submergence ratios: different dimensions and different positions of vortices around the spur dike.

关键词： T-shaped spur dike flow pattern submergence ratio SSIIM model

On braced trapezoidal corrugated steel shear panels: An experimental and numerical study

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Frontiers of Structural and Civil Engineering 2023年第3期17卷 396-410页

作者： Vahid AMIRI Arash akbari HAMED Karim ABEDI Faculty of Civil Engineering Sahand University of TechnologyTabriz ***Iran

In this study,a new system consisting of a combination of braces and steel infill panels called the braced corrugated steel shear panel(BCSSP)is *** obtain the hysteretic behavior of the proposed system,the quasistatic cyclic performances of two experimental specimens were first *** finite element modeling method was then verified based on the obtained experimental *** numerical evaluations were carried out to investigate the effects of different parameters on the ***,a relationship was established to estimate the buckling shear strength of the system without considering residual *** results obtained from the parametric study indicate that the corrugated steel shear panel(CSSP)with the specifications of a=30 mm,t=2 mm,andθ=90°had the highest energy dissipation capacity and ultimate strength while the CSSP with the specifications of a=30 mm,t=2 mm,andθ=30°had the highest initial *** can thus be concluded that the latter CSSP has the best structural performance and that increasing the number of corrugations,corrugation angle,and plate thickness and decreasing the sub-panel width generally enhance the performance of CSSPs in terms of the stability of their hysteretic behaviors.

关键词： trapezoidal corrugated plate steel shear panel braced steel shear panel experimental study buckling resistance