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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

Three-dimensional heat transfer in a particulate bed in a rotary drum studied via the discrete element method

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Particuology 2020年第4期18卷 155-162页

作者： Esmaeil Yazdani seyed hassan Hashemabadi Computational Fluid Dynamics(CFD)Research Laboratory School of ChemicalPetroleum and Gas EngineeringIran University of Science and Technology(IUST)16846-13114 TehranIran

We simulated three-dimensional heat transfer inside a horizontal rotating drum using the discrete element method and a thermal conduction *** aim was to determine the effect of end-wall heating on thermal behavior of a granular *** simulation showed that the end-wall heating significantly affects the axial temperature profile of the bed,particularly when the length-to-diameter ratio is *** near the wall heated faster and became more thermally uniform than those in the center of the *** region affected by the end heating gradually increased over *** the rotation speed enhanced the heat conduction rate,and increasing the fill level reduced the mean temperature and thermal uniformity of the granular *** transfer was also simulated for drums with different length-to-diameter ratios.

关键词： Discrete element method Three-dimensional heat transfer Rotary drum Numerical simulation Axial temperature Particulate bed

Simulation of quantum-well slipping effect on optical bandwidth in transistor laser

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Chinese Optics Letters 2009年第5期7卷 435-436页

作者： hassan Kaatuzian seyed Iman Taghavi Photonics Research Laboratory Electrical Engineering DepartmentAmirkabir University of Technology

An optical bandwidth analysis of a quantum-well （16 nm） transistor laser with 150-μm cavity length using a charge control model is reported in order to modify the quantum-well location through the base region. At constant bias current, the simulation shows significant enhancement in optical bandwidth due to moving the quantum well in the direction of collector-base junction. No remarkable resonance peak, limiting factor in laser diodes, is observed during this modification in transistor laser structure. The method can be utilized for transistor laser structure design.

关键词： well Simulation of quantum-well slipping effect on optical bandwidth in transistor laser

Application of computational fluid dynamics in design of viscous dampers-CFD modeling and full-scale dynamic testing

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Earthquake Engineering and Engineering Vibration 2023年第4期22卷 1065-1080页

作者： hassan Lak seyed Mehdi Zahrai seyed Mohammad Mirhosseini Ehsanollah Zeighami Department of Civil Engineering Collage of EngineeringArak BranchIslamic Azad UniversityArak ***Iran School of Civil Engineering College of EngineeringUniversity of TehranTehran ***Iran

Computational fluid dynamics(CFD)provides a powerful tool for investigating complicated fluid *** paper aims to study the applicability of CFD in the preliminary design of linear and nonlinear fluid viscous *** fluid viscous dampers were designed based on CFD *** first device was a linear viscous damper with straight *** second was a nonlinear viscous damper containing a one-way pressure-responsive valve inside its *** dampers were detailed based on CFD simulations,and their internal fluid flows were ***-scale specimens of both dampers were manufactured and tested under dynamic *** to the tests results,both dampers demonstrate stable cyclic behaviors,and as expected,the nonlinear damper generally tends to dissipate more energy compared to its linear *** compatibility was achieved between the experimentally measured damper force-velocity curves and those estimated from CFD *** a thermography camera,a rise in temperature of the dampers was measured during the *** was found that output force of the manufactured devices was virtually independent of temperature even during long duration ***,temperature dependence can be ignored in CFD models,because a reliable temperature compensator mechanism was used(or intended to be used)by the damper manufacturer.

关键词： fluid viscous damper passive control dynamic testing energy dissipation device computational fluid dynamic thermography

Design of Second Order Sliding Mode and Sliding Mode Algorithms:A Practical Insight to DC-DC Buck Converter

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IEEE/CAA Journal of Automatica Sinica 2017年第3期4卷 483-497页

作者： seyed Mehdi RakhtAla Monazzahalsadat Yasoubi hassan HosseinNia Department of Electrical Engineering Golestan University Department of Electrical and Computer Engineering Concordia University Department of Precision and Microsystem Engineering Delft University of Technology

This paper presents a simple and systematic approach to design second order sliding mode controller for buck *** second order sliding mode control(SOSMC)based on twisting algorithm has been implemented to control buck switch mode *** idea behind this strategy is to suppress chattering and maintain robustness and finite time convergence properties of the output voltage error to the equilibrium point under the load variations and parametric *** addition,the influence of the twisting algorithm on the performance of closed-loop system is investigated and compared with other algorithms of first order sliding mode control such as adaptive sliding mode control(ASMC),nonsingular terminal sliding mode control(NTSMC).In comparative evaluation,the transient response of the output voltage with the step change in the load and the start-up response of the output voltage with the step change in the input voltage of buck converter were *** results were obtained from a hardware setup constructed in ***,for all of the surveyed control methods,the theoretical considerations,numerical simulations,and experimental measurements from a laboratory prototype are compared for different operating *** is shown that the proposed twisting method presents an improvement in steady state error and settling time of output voltage during load changes.

关键词： DC-DC buck converter non-singular-terminal sliding mode second order sliding mode twisting algorithm

A model-driven approach to semi-structured database design

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Frontiers of Computer Science 2015年第2期9卷 237-252页

作者： Amir JAHANGARD-RAFSANJANI seyed-hassan MIRIAN-HOSSEINABADI Department of Computer Engineering Sharif University of Technology Tehran 11365-11155 Iran

Recently XML has become a standard for data representation and the preferred method of encoding struc- tured data for exchange over the Internet. Moreover it is fre- quently used as a logical format to store structured and semi- structured data in databases. We propose a model-driven and configurable approach for modeling hierarchical XML data using object role modeling （ORM） as a flat conceptual model. First a non-hierarchical conceptual schema of the problem domain is built using ORM and then different hierarchical views of the conceptual schema or parts of it are specified by the designer using transformation rules. A hierarchical mod- eling notation called H-ORM is proposed to show these hier- archical views and model more complex semi-structured data constructs and constraints. We also propose an algorithm to map hierarchical H-ORM views to XML schema language.

关键词： semi-structured database design object rolemodeling model driven approach

A novel technology for control of variable speed pumped storage power plant

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Journal of Central South University 2016年第8期23卷 2008-2023页

作者： seyed Mohammad hassan Hosseini Mohammad Reza Semsar Department of Electrical Engineering Islamic Azad University

Variable speed pumped storage machines are used extensively in wind power plant and pumped storage power plant. This paper presents direct torque and flux control(DTFC) of a variable speed pumped storage power plant(VSPSP). By this method both torque and flux have been applied to control the VSPSP. The comparison between VSPSP's control strategies is studied. At the first, a wind turbine with the capacity 2.2 k W and DTFC control strategies simulated then a 250 MW VSPSP is simulated with all of its parts(including electrical, mechanical, hydraulic and its control system) by MATLAB software. In all of simulations, both converters including two-level voltage source converter(2LVSC) and three-level voltage source converter(3LVSC) are applied. The results of applying 2LVSC and 3LVSC are the rapid dynamic responses with better efficiency, reducing the total harmonic distortion(THD) and ripple of rotor torque and flux.

关键词： direct torque and flux control(DTFC) two-level & three-level voltage source converter(2LVSC&3LVSC) variable speed pumped storage power plant(VSPSP)

A Feature Model Based Framework for Refactoring Software Product Line Architecture

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Journal of Computer Science & Technology 2016年第5期31卷 951-986页

作者： Mohammad Tanhaei Jafar Habibi seyed-hassan Mirian-Hosseinabadi Department of Computer Engineering Sharif University of Technology Tehran 11155-9517 Iran

Software product line （SPL） is an approach used to develop a range of software products with a high degree of similarity. In this approach, a feature model is usually used to keep track of similarities and differences. Over time, as modifications are made to the SPL, inconsistencies with the feature model could arise. The first approach to dealing with these inconsistencies is refactoring. Refactoring consists of small steps which, when accumulated, may lead to large-scale changes in the SPL, resulting in features being added to or eliminated from the SPL. In this paper, we propose a framework for refactoring SPLs, which helps keep SPLs consistent with the feature model. After some introductory remarks, we describe a formal model for representing the feature model. We express various refactoring patterns applicable to the feature model and the SPL formally, and then introduce an algorithm for finding them in the SPL. In the end, we use a real-world case study of an SPL to illustrate the applicability of the framework introduced in the paper.

关键词： software product line feature model refactoring software architecture

An extended discrete particle swarm optimization algorithm for the dynamic facility layout problem

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Journal of Zhejiang University-Science A(Applied Physics & Engineering) 2009年第4期10卷 520-529页

作者： hassan REZAZADEH Mehdi GHAZANFARI Mohammad SAIDI-MEHRABAD seyed JAFAR SADJADI Department of Industrial Engineering Iran University of Science and TechnologyNarmak Tehran Iran

We extended an improved version of the discrete particle swarm optimization (DPSO) algorithm proposed by Liao et al.(2007) to solve the dynamic facility layout problem (DFLP). A computational study was performed with the existing heuristic algorithms, including the dynamic programming (DP), genetic algorithm (GA), simulated annealing (SA), hybrid ant system (HAS), hybrid simulated annealing (SA-EG), hybrid genetic algorithms (NLGA and CONGA). The proposed DPSO algorithm, SA, HAS, GA, DP, SA-EG, NLGA, and CONGA obtained the best solutions for 33, 24, 20, 10, 12, 20, 5, and 2 of the 48 problems from (Balakrishnan and Cheng, 2000), respectively. These results show that the DPSO is very effective in dealing with the DFLP. The extended DPSO also has very good computational efficiency when the problem size increases.

关键词： Dynamic facility layout problem (DFLP) Particle swarm optimization (PSO) Optimization Heuristic method