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Second-Order Finite Difference/Spectral Element Formulation for Solving the Fractional Advection-Diffusion Equation

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Communications on Applied Mathematics and Computation 2020年第4期2卷 653-669页

作者： mostafa Abbaszadeh Hanieh Amjadian Department of Applied Mathematics Faculty of Mathematics and Computer SciencesAmirkabir University of TechnologyNo.424Hafez Ave.Tehran 15914Iran

The main aim of this paper is to analyze the numerical method based upon the spectral element technique for the numerical solution of the fractional advection-diffusion *** time variable has been discretized by a second-order finite difference *** stability and the convergence of the semi-discrete formula have been ***,the spatial variable of the main PDEs is approximated by the spectral element *** convergence order of the fully discrete scheme is *** basis functions of the spectral element method are based upon a class of Legendre *** numerical experiments confirm the theoretical results.

关键词： Spectral method Finite diference method Fractional advection-difusion equation Galerkin weak form Unconditional stability

Experimental investigation of flow and distortion mitigation by mechanical vortex generators in a coupled serpentine inlet-turbofan engine system

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Chinese Journal of Aeronautics 2020年第5期33卷 1375-1391页

作者： Iman MAGHSOUDI Mohammad Ali VAZIRY mostafa MAHMOODI Department of Aerospace Malek-Ashtar University of TechnologyTehran 158751774Iran Department of Aerospace Malek-Ashtar University of TechnologyIsfahanShahinshahr 115/83145Iran

The performance of compact,aggressive ducts in advanced propulsion systems is limited by the internal flow separation coupled with the formation of secondary counter-rotating vortices that give rise to intensive flow distortions at the duct *** experimental investigation was conducted to study the flow field and passive suppression of flow separation and Aerodynamic Interface Plane (AIP) distortion in a serpentine air inlet *** were performed by a turbofan engine at several Engine Operating Points (EOPs) from 56%(idle) to 100%(max).A large total pressure deficit region arose at the upper part of the AIP,which was associated with the upper surface flow *** the new mechanical S-type vortex generators in two longitudinal positions (VGl and VG2),separation and loss were diminished at the upper part of the duct and *** VG2 arrangement attained the maximum reductions in distortion coefficients which were 73.72%,60.7% and 37.8% in DC(90°),DC(60°) and△P_C/P metrics,*** the next step of the study,some unsteady aspects of the flow field were analyzed inside the *** separation onset and reattachment points were determined by the standard deviation of static pressure on the upper *** AIP spectral distribution showed that the boundary of low pressure and high pressure recovery regions was dominated by the maximum ***,the PSD diagram of several probes at AIP revealed the vortex shedding frequency and its higher harmonics at separation *** energy content of distinct unsteady spectral features in the bare configuration was significantly reduced using VGs,which showed the improvement of flow at the duct exit.

关键词： Distortion coefficient Power spectral density Serpentine inlet Total pressure Vortex generators

Partially decoupling and collar bonding of the encapsulated rebar rockbolts to improve their performance in seismic prone deep underground excavations

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International Journal of Mining Science and Technology 2019年第3期29卷 409-418页

作者： Reza Masoudi mostafa Sharifzadeh Masoud Ghorbani Department of Mining & Metallurgical Engineering Curtin UniversityWestern Australian School of Mines (WASM)Australia Department of Mining Metallurgy and Petroleum EngineeringAmirkabir University of Technology (Tehran Polytechnic)TehranIran

Rockbolt is widely employed all over the world as an effective ground reinforcement element in order to secure the underground *** encapsulated rebar or rebar rockbolt is most popular and commonly used as reinforcement in a ground support system because of its accessibility,cost effectiveness and easy *** elements in a seismic condition such as rock burst have to dissipate the energy release of the dynamic impact via their deformation and ultimate load capacity,knowing that the former is more *** other words,achieving early stiff behaviour along with large deformation capacity in rockbolts are the goals for new development in rock *** rockbolts are expensive while some of them have large deformation capability with low ultimate load *** this paper,modifications were made on encapsulation of rebar rockbolts to utilise it effectively as a yielding reinforcement in seismic *** a sufficient decoupled length in the shank of rebar rockbolts which industry has regularly been using to control the bulking of the stress fractured ground,improves the deformation capacity of the ***,leaving a collar bonding underneath of the bearing pad and plate removes the weaknesses of the head anchorage of *** the dynamic performance of the bolt is improved by these easily applicable *** behaviour and performance of encapsulated rockbolts have been discussed first,then the effects of modifications are *** proposed modification of the rebars is not only cost effective but also easy to apply in the field and improves the performance of reinforcements in seismic prone zones.

关键词： Rockbolt Tunnel support Collar bonding Seismic rock support Tunnelling

A New Kind of Generalized Pythagorean Fuzzy Soft Set and Its Application in Decision-Making

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Computer Modeling in Engineering & Sciences 2023年第9期136卷 2861-2871页

作者： Xiaoyan Wang Ahmed mostafa Khalil College of BigData Huanghai UniversityQingdaoChina Department of Mathematics Faculty of ScienceAl-Azhar UniversityAssiut71524Egypt

The aim of this paper is to introduce the concept of a generalized Pythagorean fuzzy soft set(GPFSS),which is a combination of the generalized fuzzy soft sets and Pythagorean fuzzy *** of important operations of GPFSS including complement,restricted union,and extended intersection are *** basic properties of GPFSS are ***,an algorithm of GPFSSs is given to solve the fuzzy soft ***,a comparative analysis between the GPFSS approach and some existing approaches is provided to show their reliability over them.

关键词： Pythagorean fuzzy set generalized Pythagorean fuzzy soft set algorithm decision making

Performance and characterization of iron-nickel catalysts for light olefin production

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Journal of Natural Gas Chemistry 2010年第4期19卷 422-430页

作者： mostafa Feyzi Ali Akbar Mirzaei Department of Chemistry Faculty of SciencesUniversity of Sistan & Baluchestan

A series of x （Fe,Ni）/Al2O3 catalysts （x = 2-12 wt%） were prepared using incipient wetness method and studied for the conversion of synthesis gas to light olefins.6 wt%（Fe,Ni）/Al2O3 catalyst was found to be the optimal catalyst for the production of C2-C4 *** effects of calcination behaviors and operational conditions on the catalytic performance of the optimal catalyst were *** best operational conditions were molar feed ratio H2/CO = 2/1,T = 260 ℃,gas hourly space velocity （GHSV） = 2600 h^-1 and the pressure of 3 ***-izations of both precursors and catalysts were carried out using X-ray diffraction （XRD）,temperature-programmed reduction （TPR）,scanning electron microscopy （SEM）,N2-adsorption-desorption measurement,thermal gravimetric analysis （TGA） and differential scanning calorimetry （DSC）.

关键词： calcination behaviors operational conditions catalytic performance characterization

Gorenstein n-X-Injective and n-X-Flat Modules with Respect to a Special Finitely Presented Module

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Algebra Colloquium 2021年第4期28卷 673-688页

作者： mostafa Amini Arij Benkhadra Driss Bennis Department of Mathematics Faculty of Sciences Payame Noor UniversityTehranIran Department of Mathematics Faculty of Sciences Mohammed V University in RabatRabatMorocco

Let R be a ring,X a class of R-modules and n≥1 an *** intro-duce the concepts of Gorenstein n-X-injective and n-X-flat modules via special finitely presented ***,we obtain some equivalent properties of these modules on n-X-coherent *** we investigate the relations among Gorenstein n-X-injective,n-X-flat,injective and fiat modules on X-FC-rings(i.e.,self n-X-injective and n-X-coherent rings).Several known results are generalized to this new context.

关键词： n-X-coherent ring Gorenstein n-X-injective module Gorenstein module

Study of parameters affecting infection risk from contaminated injectable products using multiple spot contamination model: a case study of insulin vials

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Journal of Chinese Pharmaceutical Sciences 2016年第11期25卷 832-837页

作者： mostafa Essam Eissa Hikma Pharma for Pharmaceutical Industry 2nd Industrial Zone

Infections of patients from consumption of contaminated pharmaceutical products constituted major health risk problems. Medicinal products are liable to microbial intrusion during in-use application. The current study focused on repeated contamination with constant level of microbiological burden by two bacteria viz. Staphylococcus aureus and Pseudomonas aeruginosa were used as dose-response models for infection through two different routes of administration. Nine different forms of insulin vials were subjected to this type of simulation study at constant assumed level of contaminations, preservative efficacy test(PET) and dose potency. Multi-spot contamination imitation study showed that initial fast rise in contamination, followed shortly by longer but steeper slope which finally turned into higher rate of contamination during the few last doses of the unit dosage forms, where the volume of the product became increasingly and progressively very small. When the probability of infection curves was constructed, both S. aureus and P. aeruginosa showed same pattern, with notably higher risk from septicemia route of the latter rather than subcutaneous route of the former. The present simulation study showed that continuous use of the same contaminated syringe progressively increased the risk of infection, especially at final few doses(between 3th and 10 th last doses depending on the dosage form sizes in the vials and the administration volumes) of the product. Small volume parenterals(SVP) are especially products at higher risk than the larger volume ones.

关键词： Insulin vials Staphylococcus aureus Pseudomonas aeruginosa Multi-spot contamination PET Simulation study

Hybrid Dynamic Neural Network and PID Control of Pneumatic Artificial Muscle Using the PSO Algorithm

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International Journal of Automation and computing 2020年第3期17卷 428-438页

作者： Mahdi Chavoshian mostafa Taghizadeh Mahmood Mazare School of Mechanical Engineering Sh.Beheshti UniversityTehran 16589-53571Iran

Pneumatic artificial muscles(PAM)have been recently considered as a prominent challenge regarding pneumatic actuators specifically for rehabilitation and medical *** accomplishing accurate control of the PAM is comparatively complicated due to time-varying behavior,elasticity and ambiguous characteristics,a high performance and efficient control approach should be *** of the mentioned challenges,limited course length is another predicament with the PAM *** this regard,this paper proposes a new hybrid dynamic neural network(DNN)and proportional integral derivative(PID)controller for the position of the *** order to enhance the proficiency of the controller,the problem under study is designed in the form of an optimization *** the potential of particle swarm optimization,it has been applied to optimally tune the PID-DNN *** verify the performance of the proposed controller,it has been implemented on a real-time system and compared to a conventional sliding mode *** and experimental results show the effectiveness of the proposed controller in tracking the reference signals in the entire course of the PAM.

关键词： Dynamic neural network(DNN)control hybrid control pneumatic muscle particle swarm optimization sliding mode control

Correlation between microstructural features and tensile strength for friction welded joints of AA-7005 aluminum alloy

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Journal of Central South University 2016年第8期23卷 1839-1846页

作者： Seyyed mostafa Tahsini Ayyub Halvaee Hamed Khosravi School of Metallurgy and Materials Engineering College of Engineering University of Tehran Department of Materials Engineering Faculty of Engineering University of Sistan and Baluchestan

Similar friction welded joints of AA-7005 aluminum rods were fabricated using different combinations of process parameters such as friction pressure(1.0, 1.5 and 2.0 MPa) and friction time(10, 15 and 20 s). Interfacial microstructure and formation of intermetallic compounds at the joint interface were evaluated via scanning electron microscopy(SEM) equipped with energy dispersive spectrum(EDS), and optical microscopy(OM). Microstructural observations reveal the formation of intermetallic phases during the welding process which cannot be extruded from the interface. Theses phases influence the tensile strength of the resultant joints. From the tensile characteristics viewpoint, the greatest tensile strength value of 365 MPa is obtained at 1.5 MPa and 15 s. Finally, the role of microstructural features on tensile strength of resultant joints is discussed.

关键词： friction welding AA-7005 aluminum alloy microstructure intermetallics tensile strength