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A new framework for selection of representative samples for special core analysis

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Petroleum Research 2020年第3期5卷 210-226页

作者： Abouzar Mirzaei-Paiaman seyed reza asadolahpour Hadi Saboorian-Jooybari Zhangxin Chen Mehdi Ostadhassan National Iranian South Oil Company(NISOC) Department of Petroleum EngineeringAhvazIran Now at State University of Campinas(UNICAMP) CampinasSPBrazil Department of Chemical and Petroleum Engineering Schulich School of EngineeringUniversity of CalgaryCanada Key Laboratory of Continental Shale Hydrocarbon Accumulation and Efficient Development Ministry of EducationNortheast Petroleum University

Special core analysis(SCAL)measurements play a noteworthy role in reservoir *** to the time-consuming and costly character of these measurements,routine core analysis(RCAL)data should be inspected thoroughly to select a representative subset of samples for *** are no comprehensive guidelines on how representative samples should be *** this study,a new framework is presented for selection of representative samples for *** foundation of this framework is using methods of PSRTI,FZI*(FZI-star)and TEM-function for the early estimation of petrophysical static,dynamic,and pseudo-static rock types at RCAL *** global hydraulic element(GHE)approach is benefitted and a FZI*-based GHE method(i.e.,GHE*)is presented for partitioning *** framework takes into consideration different laboratory,reservoir engineering,geological,petrophysical and statistical factors.A carbonate reservoir case is presented to support our *** also show that the current forms of Lorenz and Stratigraphic Modified Lorenz Plots in reservoir engineering are not appropriate,and present new forms of them.

关键词： RCAL SCAL Sample selection Rock typing TEM-Function

New insights on the role of chondroitin sulfate proteoglycans in neural stem cell–mediated repair in spinal cord injury

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Neural Regeneration Research 2025年第6期20卷 1699-1700页

作者： seyed Mojtaba Hosseini Soheila Karimi-Abdolrezaee Department of Physiology and Pathophysiology Spinal Cord Research CentreRady Faculty of Health SciencesUniversity of ManitobaWinnipegMBCanada Manitoba Multiple Sclerosis Research Center WinnipegMBCanada Children Hospital Research Institute of Manitoba WinnipegMBCanada

Extensive neurodegeneration is a hallmark of traumatic spinal cord injury (SCI) that underlies permanent sensorimotor and autonomic impairments (Alizadeh et al.,2019).Following the primary impact,the spinal cord undergoes a cascade of secondary injury mechanisms that are driven by disruption of the blood-spinal cord ba rrier,vascula r inju ry,glial reactivity,neu roinfla mmation,oxidative stress,lipid peroxidation,and glutamate excitotoxicity that culminate in neuronal and oligodendroglial cell death,demyelination,and axonal damage(Alizadeh et al.,2019).To achieve a meaningful functional recovery after SCI,regeneration of new neurons and oligodendrocytes and their successful growth and integration within the neural network are critical steps for reconstructing the damaged spinal cord tissue (Fischer et al.,2020).

关键词： peroxidation Fischer injury

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

Numerical and Performance Analysis of one row Transonic Rotor with Sweep and Lean angle

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Journal of Thermal Science 2014年第5期23卷 438-445页

作者： seyed reza Razavi Masoud Boroom Aerospace Engineering Department AmirKabir University of Technology

In this study,aerodynamic behaviors of swept and leaned blades were *** and tangential blade curvatures impacts on compressor's operating parameters were analyzed separately.A commercial CFD program which solves the Reynolds-averaged Navier-Stokes equations was used to find out the mentioned impact and the complicated flow field of transonic *** CFD method that was used for solving flow field's equation was validated by experimental data of NASA Rotor *** results showed that the compressor with curved rotors had higher efficiency,rotor pressure ratio and stable operating range compared to the compressor with un-curved *** curved rotors mostly had higher impact on the overall stable operating range compared to the other operating *** range involves choking point and stall point that were changed separately by using of bended *** finding the detailed impact of sweep and lean angle on transonic blades,various forms of lean and sweep angles were exerted to basic *** was found that sweep angles increased overall operating range up to 30%,efficiency up to 2%and pressure ratio up to 1%.Leaning the blades increased the safe operating range,the pressure ratio and efficiency by 14%,4%and 2%respectively.

关键词： compressor performance efficiency stable operational range surge improvement swept Rotor leaned rotor

On the Nonorientable Genus of the Generalized Unit and Unitary Cayley Graphs of a Commutative Ring

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Algebra Colloquium 2022年第1期29卷 167-180页

作者： Mahdi reza Khorsandi seyed reza Musawi Faculty of Mathematical Sciences Shahrood University of Technology P.O.Box 36199-95161ShahroodIran

Let R be a commutative ring and U(R)the multiplicative group of unit elements of *** 2012,Khashyarmanesh et *** the generalized unit and unitary Cayley graph,T(R,G,S),corresponding to a multiplicative subgroup G of U(R)and a nonempty subset S of G with S^(-1)={s^(-1)|s∈S}■S,asthegraphwithvertexsetR and two distinct vertices x and y being adjacent if and only if there exists s∈S such that x+sy∈*** this paper,we characterize all Artinian rings R for which T(R,U(R),S)is *** leads us to determine all Artinian rings whose unit graphs,unitary Cayley graphs and co-maximal graphs are *** addition,we prove that for an Artinian ring R for which T(R,U(R),S)has finite nonorientable genus,R must be a finite ***,it is proved that for a given positive integer k,the number of finite rings R for which T(R,U(R),S)has nonorientable genus k is finite.

关键词： unit graph unitary Cayley graph co-maximal graph projective graph nonorientable genus

New approach to solving master equations of density operator for the Jaynes Cummings model with cavity damping

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Chinese Physics B 2014年第9期23卷 65-70页

作者： seyed Mahmoud Ashrafi Mohammad reza Bazrafkan Physics Department Faculty of ScienceI.K.I.University

By introducing thermo-entangled state representation Ⅰη〉, which can map master equations of density operator in quantum statistics as state-vector evolution equations, and using ＂dissipative interaction picture＂ we solve the master equation of Jaynes-Cummings model with cavity damping. In addition we derive the Wigner function for density operator when the atom is initially in the up state Ⅰ↑〉 and the cavity mode is in coherent state.

关键词： Jaynes-Cummings model entangled state representation master equations

Multidisciplinary design optimization of a dual-spin guided vehicle

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Defence Technology（防务技术） 2024年第7期37卷 133-148页

作者： Jalal Karimi Mohammad reza Rajabi seyed Hossein Sadati seyed Mahid Hosseini Department of Aerospace Engineering Malek Ashtar University of TechnologyTehranIran

In this research,a Multidisciplinary Design Optimization approach is proposed for the dual-spin guided flying projectile design considering external and internal parts of the body as design *** this way,a parametric formulation is *** related disciplines,including structure,aerodynamics,guidance,and control are *** total mass,maximum aerodynamic control effectiveness,minimum miss distance,maximum yield stress in all subsystems,controllability and gyroscopic stability constraints are some of objectives/constraints taken into *** problem is formulated in All-At-Ones Multidisciplinary Design Optimization approach structure and solved by Simulated Annealing and minimax *** optimal configurations are evaluated in various *** resulted optimal configurations have met all design objectives and constraints.

关键词： Flying projectile optimal design All-at-ones multidisciplinary optimization Structure discipline Guidance and control discipline Aerodynamic discipline

A novel control strategy based on a look-up table for optimal operation of MTDC systems in post-contingency conditions

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Protection and Control of Modern Power Systems 2022年第1期7卷 40-50页

作者： seyed Mohsen Alavi reza Ghazi Department of Electrical Engineering Ferdowsi University of MashhadMashhadIran

Multi terminal VSC-HVDC systems are a promising solution to the problem of connecting offshore wind farms to AC *** power sharing and appropriate control of DC-link voltages are essential and must be maintained dur-ing the operation of VSC-MTDC systems,particularly in post-contingency *** traditional droop control methods cannot satisfy these requirements,and accordingly,this paper proposes a novel centralized control strategy based on a look-up table to ensure optimal power sharing and minimum DC voltage deviation immediately during post-contingency conditions by considering converter *** also reduces destructive effects(e.g.,frequency devia-tion)on onshore AC grids and guarantees the stable operation of the entire MTDC *** proposed look-up table is an array of data that relates operating conditions to optimal droop coefficients and is determined according to N-1 contingency analysis and a linearized system *** constraints and contingencies such as wind power changes,converter outage,and DC line disconnection are considered in its formation *** performed on a 4-terminal VSC-MTDC system in the MATLAB-Simulink environment validate the effectiveness and superiority of the proposed control strategy.

关键词： Optimal power sharing DC voltage deviation Adaptive droop control Multi-terminal HVDC(MTDC) Voltage source converter(VSC)

Fault ride-through capability improvement in a DFIG-based wind turbine using modified ADRC

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Protection and Control of Modern Power Systems 2022年第1期7卷 751-787页

作者： seyed reza Mosayyebi seyed Hamid Shahalami Hamed Mojallali Electrical Engineering Department Faculty of EngineeringUniversity of GuilanRashtIran

In this paper,an overview of several strategies for fault ride-through(FRT)capability improvement of a doubly-fed induction generator(DFIG)-based wind turbine is *** and parameter variations have adverse effects on the performance of these *** is desirable to use a control method that is robust to such *** disturbance rejection control(ADRC)is one of the most common methods for eliminating the effects of *** improve the performance of the conventional ADRC,a modified ADRC is introduced that is more robust to disturbances and offers better *** non-derivability of the fal function used in the conventional ADRC degrades its efficiency,so the modified ADRC uses alternative functions that are derivable at all points,i.e.,the odd trigonometric and hyperbolic functions(arcsinh,arctan,and tanh).To improve the effciency of the proposed ADRC,fuzzy logic and fractional-order functions are used *** fuzzy fractional-order ADRC(FFOADRC),all disturbances are evaluated using a nonlinear fractional-order extended state observer(NFESO).The performance of the suggested structure is investigated in MATLAB/*** simulation results show that during disturbances such as network voltage sag/swell,using the modified ADRCs leads to smaller fluctuations in stator flux amplitude and DC-link voltage,lower variations in DFIG velocity,and lower total harmonic distortion(THD)of the stator *** demonstrates the superiority over conventional ADRC and a proportional-integral(PI)***,by chang-ing the crowbar resistance and using the modified ADRCs,the peak values of the waveforms(torque and currents)can be controlled at the moment of fault occurrence with no significant distortion.

关键词： Doubly-fed induction generator(DFIG) Auto disturbance rejection control(ADRC) Fault ride-through(FRT) Wind turbine Nonlinear fractional-order extended state observer(NFESO)