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Weak gravitational lensing of quantum perturbed lukewarm black holes and cosmological constant effect

Research in Astronomy and Astrophysics 2017年第6期17卷 17-36页

作者： Hossein Ghaffarnejad mojtaba amir mojahedi Faculty of Physics Semnan University Semnan 35131-19111 Iran

The aim of the paper is to study weak gravitational lensing of quantum （perturbed） and classical lukewarm black holes （QLBHs and CLBHs respectively） in the presence of cosmological parameter A. We apply a numerical method to evaluate the deflection angle of bending light rays, image locations θ of sample sourceβ = π- 4, and corresponding magnifications μ. There are no obtained real values for Einstein ring locations θE（β = 0） for CLBHs but we calculate them for QLBHs. As an experimental test of our calculations, we choose mass M of 60 types of the most massive observed galactic black holes acting as a gravitational lens and study quantum matter field effects on the angle of bending light rays in the presence of cosmological constant effects. We calculate locations of non-relativistic images and corresponding magnifications. Numerical diagrams show that the quantum matter effects cause absolute values of the quantum deflection angle to be reduced with respect to the classical ones. The sign of the quantum deflection angle is changed with respect to the classical values in the presence of the cosmological constant. This means dominance of the anti-gravity counterpart of the cosmological horizon on the angle of bending light rays with respect to absorbing effects of 60 local types of the most massive observed black holes. Variations of the image positions and magnifications are negligible when increasing dimensionless cosmological constant ∈ = 16AM2 /2The deflection angle takes positive （negative） values for CLBHs （QLBHs） and they decrease very fast （slowly） by increasing the closest distance x0 of bending light ray and/or dimensionless cosmological parameter for sample giant black holes with 0.001 〈 ∈ 〈 0.01.

关键词： gravitational lensing weak - strong - micro - stars black holes

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Predication of discharge coefficient of cylindrical weir- gate using adaptive neuro fuzzy inference systems （ANFIS）

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Frontiers of Structural and Civil Engineering 2017年第1期11卷 111-122页

作者： Abbas PARSAIE amir Hamzeh HAGHIABI mojtaba SANEIE Hasan TORABI Department of Water Engineering Lorestan University Khorramabad Iran Soil Conservation and Watershed Management Research Institute Tehran Iran

Settlement of sediments behind weirs and accumulation of materials floating on water behind gates decreases the performance of these structures. Weir-gate is a combination of weir and gate structures which solves them Infirmities. Proposing a circular shape for crest of weirs to improve their performance, investigators have proposed cylindrical shape to improve the performance of weir-gate structure and call it cylindrical weir-gate. In this research, discharge coefficient of weir-gate was predicated using adaptive neuro fuzzy inference systems （ANFIS）. To compare the performance of ANFIS with other types of soft computing techniques, multilayer perceptron neural network （MLP） was prepared as well. Results of MLP and ANFIS showed that both models have high ability for modeling and predicting discharge coefficient; however, ANFIS is a bit more accurate. The sensitivity analysis of MLP and ANFIS showed that Froude number of flow at upstream of weir and ratio of gate opening height to the diameter of weir are the most effective parameters on discharge coefficient.

关键词： weir-gate soft computing crest geometry circular crest weir cylindrical shape

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Polyurethane-SAPO-34 mixed matrix membrane for CO_2/CH_4 and CO_2/N_2 separation

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Chinese Journal of Chemical Engineering 2019年第2期27卷 322-334页

作者： Gholamhossein Sodeifian mojtaba Raji Morteza Asghari Mashallah Rezakazemi amir Dashti Department of Chemical Engineering Faculty of Engineering University of Kashan Faculty of Chemical and Materials Engineering Shahrood University of Technology

SAPO-34 nanocrystals(inorganic filler) were incorporated in polyurethane membranes and the permeation properties of CO_2, CH_4,and N_2 gases were explored. In this regard, the synthesized PU-SAPO-34 mixed matrix membranes(MMMs) were characterized via SEM, AFM, TGA, XRD and FTIR analyses. Gas permeation properties of PU-SAPO-34 MMMs with SAPO-34 contents of 5 wt%, 10 wt% and 20 wt% were investigated. The permeation results revealed that the presence of 20 wt% SAPO-34 resulted in 4.45%, 18.24% and 40.2% reductions in permeability of CO_2,CH_4,and N_2, respectively, as compared to the permeability of neat polyurethane membrane. Also,the findings showed that at the pressure of 1.2 MPa, the incorporation of 20 wt% SAPO-34 into the polyurethane membranes enhanced the selectivity of CO_2/CH_4 and CO_2/N_2, 14.43 and 37.46%, respectively. In this research, PU containing 20 wt% SAPO-34 showed the best separation performance. For the first time, polynomial regression(PR) as a simple yet accurate tool yielded a mathematical equation for the prediction of permeabilities with high accuracy(R^2>99%).

关键词： Membrane Polyurethane Gas separation Permeability Selectivity Mathematical model

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Geyser Inspired Algorithm:A New Geological-inspired Meta-heuristic for Real-parameter and Constrained Engineering Optimization

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Journal of Bionic Engineering 2024年第1期21卷 374-408页

作者： mojtaba Ghasemi Mohsen Zare amir Zahedi Mohammad-Amin Akbari Seyedali Mirjalili Laith Abualigah Department of Electronics and Electrical Engineering Shiraz University of TechnologyShirazIran Department of Electrical Engineering Faculty of EngineeringJahrom UniversityJahromFrasIran Department of Electrical and Computer Engineering Tarbiat Modares UniversityTehranIran Department of Electrical and Computer Engineering University ofCyprusNicosiaCyprus Centre for Artificial Intelligence Research and Optimisation Torrens University AustraliaBrisbaneQLD 4006Australia University Research and Innovation Center Obuda University1034 BudapestHungary Department of Electrical and Computer Engineering Lebanese American UniversityByblos 13-5053Lebanon Hourani Center for Applied Scientific Research Al-Ahliyya Amman UniversityAmman 19328Jordan MEU Research Unit Middle East UniversityAmman 11831Jordan Applied Science Research Center Applied Science Private UniversityAmman 11931Jordan

Over the past years,many efforts have been accomplished to achieve fast and accurate meta-heuristic algorithms to optimize a variety of real-world *** study presents a new optimization method based on an unusual geological phenomenon in nature,named Geyser inspired Algorithm(GEA).The mathematical modeling of this geological phenomenon is carried out to have a better understanding of the optimization *** efficiency and accuracy of GEA are verified using statistical examination and convergence rate comparison on numerous CEC 2005,CEC 2014,CEC 2017,and real-parameter benchmark ***,GEA has been applied to several real-parameter engineering optimization problems to evaluate its *** addition,to demonstrate the applicability and robustness of GEA,a comprehensive investigation is performed for a fair comparison with other standard optimization *** results demonstrate that GEA is noticeably prosperous in reaching the optimal solutions with a high convergence rate in comparison with other well-known nature-inspired algorithms,including ABC,BBO,PSO,and *** that the source code of the GEA is publicly available at https://***/projects/gea.

关键词： Nature-inspired algorithms Real-world and engineering optimization Mathematical modeling Geyser algorithm(GEA)

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Case study of hydraulic fracturing in an offshore carbonate oil reservoir

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Petroleum Research 2022年第4期7卷 419-429页

作者： Mohammad Azad mojtaba Ghaedi amir Farasat Hadi Parvizi Hamed Aghaei Department of Petroleum Engineering School of Chemical and Petroleum EngineeringShiraz UniversityIran Iranian Offshore Oil Company TehranIran Petroxin Ltd LondonUnited Kingdom

Maximizing petroleum production while efficiently managing the operational costs is the oil and gas industry's primary goal which requires innovative engineering approaches and production-enhancing treatments such as hydraulic fracturing(HF).During the HF process,the injected fluid mixed with sands or proppants will create permanent fluid channels to drain more of the reservoir *** level of complexity and various constraints involved in real field treatments have made HF even more chal-lenging in layered carbonate reservoirs with the water drive mechanism.A prominent concern is the downward fracture growth to the oil/water contact zone that may cause unfavorable water cut *** fracture height confinement criterion necessitates optimization of fracture dimension *** height development is mainly a function of in-situ stress conditions and stress magnitude differences between geologic *** cases with a water table at the proximity of the wellbore,fracture height directly affects the operational *** paper demonstrates a practical step-by-step approach towards the design of hydraulic fracturing treatment in an offshore carbonate oil *** modeling process involves optimization of the location,number,and conductivity of the proposed ***-jection of high viscosity fluid causes a bi-wing vertical planar fracture to propagate perpendicular to the direction of minimum horizontal stress in the strike-slip faulting *** of the induced hydraulic fractures are also impacted by the amount and type of ***,as with this case study,the magnitude of vertical stress is in the same range as the maximum horizontal stress;the fracture height growth is the limiting *** LGR method is used to define fractures in the dynamic reservoir model which has been built based on a complete set of data ranging from the analyses of logs,core samples,and seismic details,to perform production forecasts and economic ev

关键词： Hydraulic fracture design Carbonate reservoirs Proppant selection Economic analysis Reservoir modeling

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A Global Best-guided Firefly Algorithm for Engineering Problems

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Journal of Bionic Engineering 2023年第5期20卷 2359-2388页

作者： Mohsen Zare mojtaba Ghasemi amir Zahedi Keyvan Golalipour Soleiman Kadkhoda Mohammadi Seyedali Mirjalili Laith Abualigah Department of Electrical Engineering Faculty of EngineeringJahrom UniversityJahrom***FrasIran Department of Electronics and Electrical Engineering Shiraz University of TechnologyShiraz***Iran Department of Electrical and Computer Engineering Tarbiat Modares UniversityTehran***Iran Department of Computer Engineering Sari BranchIslamic Azad UniversitySari***Iran Department of Electrical Engineering Urmia BranchIslamic Azad UniversityUrmia571696896Iran Centre for Artificial Intelligence Research and Optimisation Torrens University AustraliaBrisbaneQLD4006Australia Yonsei Frontier Lab Yonsei UniversitySeoul03722South Korea Computer Science Department Prince Hussein Bin Abdullah Faculty for Information TechnologyAl Al-Bayt UniversityMafraq25113Jordan Hourani Center for Applied Scientific Research Al-Ahliyya Amman UniversityAmman19328Jordan Faculty of Information Technology Middle East UniversityAmman11831Jordan School of Computer Sciences Universiti Sains Malaysia11800George TownPulau PinangMalaysia University Research and Innovation Center Obuda University1034BudapestHungary School of Engineering and Technology Sunway University MalaysiaPetaling Jaya27500Malaysia Applied science research center Applied science private universityAmman11931Jordan

The Firefly Algorithm(FA)is a highly efficient population-based optimization technique developed by mimicking the flashing behavior of fireflies when *** article proposes a method based on Differential Evolution(DE)/current-to-best/1 for enhancing the FA's movement *** proposed modification increases the global search ability and the convergence rates while maintaining a balance between exploration and exploitation by deploying the global best ***,employing the best solution can lead to premature algorithm convergence,but this study handles this issue using a loop adjacent to the algorithm's main ***,the suggested algorithm’s sensitivity to the alpha parameter is reduced compared to the original *** GbFA surpasses both the original and five-version of enhanced FAs in finding the optimal solution to 30 CEC2014 real parameter benchmark problems with all selected alpha ***,the CEC 2017 benchmark functions and the eight engineering optimization challenges are also utilized to evaluate GbFA’s efficacy and robustness on real-world problems against several enhanced *** all cases,GbFA provides the optimal result compared to other *** that the source code of the GbFA algorithm is publicly available at https://***/projects/gbfa.

关键词： Firefly algorithm New movement vector Global best-guided firefly algorithm Global optimization Engineering design

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On the Wear Behavior of Cyanoacrylate in Presence of Nano-Sized SiO<sub>2</sub>

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Engineering（科研） 2012年第5期4卷 245-251页

作者： amir Yaghmaei Seyed mojtaba Zebarjad Mehrdad Kashefi Department of Materials Science and Metallurgical Engineering Faculty of Engineering Ferdowsi University of Mashhad Mashhad Iran

Cyanoacrylate adhesive and its composites have been widely used in industry and dentistry. According to literature survey done by the authors, there are few papers concentrated on role of nano-sized particles on wear behavior of cyanoacrylate glue. Thus the main goal of current research focused on clarifying the role of nano-sized SiO2 on wear behavior of cyanoacrylate. Pin-on-disk wear test, SEM imaging and microhardness test was utilized to investigate wear performance of cyanoacrylate and its nanocomposites with SiO2. The results indicated that SiO2 nano powders can reduce wear rate of cyanoacrylate and change its wear mechanism. It was also shown that surface hardness of cyanoacrylate is increased by addition of nano-sized SiO2.

关键词： Cyanoacrylate SiO2 Nano Powders Wear Behavior SEM Microhardness

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Effects of Heat Treatment on Microhardness of Some Al-Cu Alloy Prepared by Vacuum Coating

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Materials Sciences and Applications 2014年第8期5卷 491-495页

作者： Safdar Habibi Babak Jaleh amir Namdarmanesh mojtaba Shamlo Physics Department Bu Ali Sina University Hamedan Iran Physics Department Payam Nour University Tehran Iran

In this paper binary alloy of Al-Cu with composition Al(100-x)Cux, (x = 10, 15, 20) is prepared by thermal evaporation method. The prepared samples are annealed at different temperatures and investigated by XRD and microhardness method. XRD has been used to show amorphous state of structures and microhrdness tester show the increase in hardness due to the increase in amount of Al in the alloy. SEM and AFM were also used to show information about the surface of the specimen, resulting some densification and relaxation in these specimens.

关键词： Al Alloy Amorphous Materials Microhardness Heat Treatment

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