Fa
  • Ph.D. (1991)

    Mechanical Engineering, Bath,

  • M.Sc. (1987)

    mechanical engineering

    , Birmingham, England

  • B.Sc. (1980)

    mechanical engineering

    , Sharif University of Technology,

  • Study of dynamic systems and determination of their sustainability range
  • Stability of micro electromechanical systems
  • Ball bearing case waviness effect on system stability
  • Bladed Disk Dynamic Stability
  • Performance and Stability Analysis of Drill-string
  • Dynamic

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I have got BSc. in 1980 from Sharif University of Technology. Then I was working in industry about 4 years. I have got MSc. in 1986 from Birmingham university. I have graduated from my Phd. in 1990 from Bath University. I have started my work as a faculty member in Tarbiat Modares University. I had cooperation with other universities including Amir Kabir, Khajeh Naseer , Shahid Abaspour, Malek Ashtar. I have got Associate Professor degree in 2010. I became full Professor in 2021. I have published about 85 papers and two books. My Research interest is systems dynamic stability. I have researches in drill string, bladed disks, rotor dynamics ,wagon stability and Coriolis flow meter and mechanisms with clearance.

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Curriculum Vitae (CV)

L-carnitine versus Propranolol for pediatric migraine prophylaxis.

Laya Amini, Omid Yaghini, Mohammadreza Ghazavi, Nahid Aslani
Journal PaperIranian Journal of Child Neurology , Volume 15 , Issue 2, 2021 April 1, {Pages }

Abstract

Objective Carnitine plays a significant role in fatty acid transportation in mitochondria and has been shown to have a prophylactic effect on adult migraine. The aim of this randomized controlled trial was to compare and evaluate the effects of L-carnitine supplementation versus propranolol in the prevention of pediatric migraine. Materials & Methods A total of 60 pediatric patients with episodic migraine were randomly allocated to 2 independent groups to receive either 50 mg/kg/day L-carnitine or 1 mg/kg/day propranolol as a prophylactic drug. Frequency, severity, and duration of migraine attacks and headache disability based on the Pediatric Migraine Disability Assessment Score (PedMIDAS) were studied at the baseline and after 2, 4, and 1

Parametric investigation of dynamics of beams made of FG material with longitudinal and whirling movements exposed to axial forces

Ali Forooghi, Mohammad Reza Ghazavi
Journal PaperJournal of Science and Technology of Composites , Volume 7 , Issue 4, 2021 February 19, {Pages 1177-1188 }

Abstract

To improve the performance of the bi-gyroscopic systems, vibration and stability of an axially graded beam with both axial and rotational motion subjected to axial load have been studied. In addition, a detailed parametric study was performed to explain the effect of various key factors such as range of axial graded of materials, type of material distribution, viscosity coefficient, rotation and axial motion on the dynamic of the system. It was assumed that the material properties of the system change linearly or exponentially in the longitudinal direction. The critical axial and rotational speeds of the system were obtained by using the Galerkin discretization technique and eigenvalue analysis. An analytical method was used to identify sys

Vibration and stability analysis of drivelines with self-excitation of non-constant velocity couplings

M SoltanRezaee, MR Ghazavi, A Najafi, WH Liao
Journal Paper , , {Pages }

Abstract

Efficacy of levetiracetam in treatment of childhood stuttering

Mohammadreza Ghazavi, Fateme Rastgu, Jafar Nasiri, Omid Yaghini
Journal PaperInternational Journal of Preventive Medicine , Volume 11 , 2020 January , {Pages }

Abstract

Background:Stuttering is a kind of speech disorder that affects about 1% of total population. As the origin of this disorder is not obviously diagnosed yet, various remedies have been practiced and among them different medicines have been studied, but unfortunately no significant effective drugs have been recognized yet. As stuttering imposes a great social and mental costs to the patients and their families, finding an effective medicine will help significantly. In this study we have focused on the effects of levetiracetam (LEV) treatment on children suffering from stuttering.Methods:In this clinical trial study, 30 children aged> 3 years (median 3.8 years) with stuttering and abnormal sleep electroencephalogram (EEG) were treated by LEV a

A comparative study on the efficacy of levetiracetam and carbamazepine in the treatment of rolandic seizures in children: An open-label randomized controlled trial

Parisa Ahadi, Jafar Nasiri, Mohammad Reza Ghazavi, Toktam Mosavian, Vahid Mansouri
Journal PaperJournal of Research in Pharmacy Practice , Volume 9 , Issue 2, 2020 April 1, {Pages 68 }

Abstract

Objective: This study was performed to investigate whether levetiracetam should be preferred to carbamazepine as a treatment choice for benign childhood epilepsy with centro Temporal spikes (BCECTS), the most common partial epilepsy of childhood. Methods: This randomized clinical trial study included 92 children with rolandic epilepsy aged 4–12 years referred to the Pediatric Neurology Clinic at Imam Hossein Hospital, Isfahan, Iran, from April 2019 to January 2020. Patients were selected consecutively and randomly assigned to two study groups (levetiracetam and carbamazepine groups). Patients were followed and revisited every 2 months for 6 months after starting the medication. The frequency and duration of seizure attacks and drug side e

On the dynamics of a novel energy harvester to convert the energy of the magnetic noise into electrical power

Ali Ghodsi, Hamid Jafari, Saber Azizi, Mohammad Reza Ghazavi
Journal PaperEnergy , Volume 207 , 2020 September 15, {Pages 118268 }

Abstract

Magnetic and mechanical noise in the frequency range of MHz are available in the environment and could be harvested for human convenience. This manuscript focuses on the dynamical behavior of hybrid magneto-mechano-electric (MME) energy harvesters to convert the energy of the magnetic noise and mechanical noise to electrical power using a composite energy scavenging structure. The proposed apparatus is composed of a piezoelectric (PZT-5A) layered beam on which a magnetostrictive material (Metglas-2605SC) is deposited. Once the device is exposed to external magnetic noise, Metglas-2605SC undergoes mechanical strain, and as a result, the mechanical strain is converted to electrical potential difference throughout the PZT-5A layer. In the pres

Herbal supplement use and herb–drug interactions among patients with kidney disease

Soroush Mohammadi, Gholamreza Asghari, Afsoon Emami-Naini, Marjan Mansourian, Shirinsadat Badri
Journal PaperJournal of Research in Pharmacy Practice , Volume 9 , Issue 2, 2020 April 1, {Pages 61 }

Abstract

Objective: The prevalence of herb–drug interactions and herb's adverse effects may be serious in susceptible population such as patients with chronic kidney disease (CKD). In this study, we planned to determine the usage prevalence of herbal products and herb–drug interactions in CKD patients. Methods: A cross-sectional prospective study was conducted on CKD and posttransplant patients with a history of using herbal supplements in Isfahan, Iran. The patients were subjected to a validated checklist, containing demographic and clinical information. The knowledge of herbal use, side effects, and herb–drug interactions was assessed based on patients' responses. Data were reported as prevalence (percent) of the occurrence. Findings: The pr

Size-dependent modal interactions of a piezoelectrically laminated microarch resonator with 3: 1 internal resonance

A Nikpourian, MR Ghazavi, S Azizi
Journal PaperApplied Mathematics and Mechanics , Volume 41 , Issue 10, 2020 October , {Pages 1517-1538 }

Abstract

The nonlinear interactions of a microarch resonator with 3: 1 internal resonance are studied. The microarch is subjected to a combination of direct current (DC) and alternating current (AC) electric voltages. Thin piezoelectric layers are thoroughly bonded on the top and bottom surfaces of the microarch. The piezoelectric actuation is not only used to modulate the stiffness and resonance frequency of the resonator but also to provide the suitable linear frequency ratio for the activation of the internal resonance. The size effect is incorporated by using the so-called modified strain gradient theory. The system is highly nonlinear due to the co-existence of the initial curvature, the mid-plane stretching resulting from clamped anchors, and

Comparing sedative effect of dexmedetomidine versus midazolam for sedation of children while undergoing computerized tomography imaging

Reza Azizkhani, Farhad Heydari, Mohammadreza Ghazavi, Maryam Riahinezhad, Mohammadreza Habibzadeh, Ali Bigdeli, Keihan Golshani, Saeid Majidinejad, Abolfazl Mohammadbeigi
Journal PaperJournal of Pediatric Neurosciences , Volume 15 , Issue 3, 2020 July 1, {Pages 245 }

Abstract

Background: Pediatric anxiety and restlessness may create issues and difficulties in performing accurate diagnostic studies even noninvasive ones, such as radiological imaging. There are some agents that will help to get this goal. This study aimed to compare the intranasal effect of dexmedetomidine (DEX) and midazolam (MID) for sedation parameters of children undergoing computerized tomography (CT) imaging. Materials and Methods: A double-blind clinical trial was conducted on 162 eligible children who underwent CT imaging. These patients were divided into two groups including MID (n= 81) with dose of 0.3 mg. kg and DEX (n= 81) with dose of 3 μg. kg, which was consumed intranasally. The mean blood pressure (MBP), respiratory rate (RR), hea

Vibro-acoustic and sound transmission loss analysis of truncated conical shell subjected to incident sound wave

Afshin Tebyanian, Mohammad Reza Ghazavi
Journal PaperJournal of Vibration and Control , Volume 25 , Issue 2, 2019 January , {Pages 435-444 }

Abstract

A combination of analytical method for shell vibration, boundary element method (BEM) for acoustic media of shell outer space, and finite element method (FEM) for shell inner space was used to study the vibro-acoustic behavior and extract sound transmission loss factor (STL) of a coupled vibro-acoustic system. The equation of motion of the shell is extracted based on the Donnell–Mushtari hypothesis and using Hamilton principles. The acoustic pressure on the outer and inner space is obtained using BEM on the defined nodes on the surface and these localized nodal pressures are converted to nodal concentrated forces. Finally, vibration of the coupled vibro-acoustic model is solved in frequency domain and vibration response of shell and acous

Size-dependent secondary resonance of a piezoelectrically laminated bistable MEMS arch resonator

Alireza Nikpourian, Mohammad Reza Ghazavi, Saber Azizi
Journal PaperComposites Part B: Engineering , Volume 173 , 2019 September 15, {Pages 106850 }

Abstract

This paper deals with the size-dependent nonlinear dynamics of a bistable fully clamped resonant shallow microarch under subharmonic resonance of order 1/2. The microarch is laminated between thin piezoelectric layers and subjected to a combination of piezoelectric and electrostatic actuations. Nonlinearities associated with clamped ends, curvature and electrostatic actuation are taken into account in the formulation of the problem. Size effect is considered using the so-called strain gradient theory, and the result is compared with the classical theory. The frequency response is numerically obtained using the shooting technique and in some cases analytically using multiple time scales method. The effect of piezoelectric actuation and the i

Size-dependent nonlinear behavior of a piezoelectrically actuated capacitive bistable microstructure

Alireza Nikpourian, Mohammad Reza Ghazavi, Saber Azizi
Journal PaperInternational Journal of Non-Linear Mechanics , Volume 114 , 2019 August 1, {Pages 49-61 }

Abstract

Size-dependent behavior of a bistable microelectromechanical system subjected to electrostatic and piezoelectric actuations is investigated. The system is comprised of an Euler–Bernoulli slightly curved capacitive microbeam which is laminated between piezoelectric layers. Applying DC voltage to piezoelectric layers induces axial force in the beam and modulates its stiffness and consequently, its frequencies. Hamilton’s principle is used to derive the governing equation of motion and the size effect is introduced into the formulation through the so-called strain gradient theory. The proposed model accounts for nonlinearities due to mid-plane stretching, curvature, and the electrostatic loading. The reduced order model is obtained via uti

Nonlinear Size-Dependent Analysis of an Initially Curved Microbeam

A Nikpourian, MR Ghazavi
Journal PaperModares Mechanical Engineering , Volume 19 , Issue 2, 2019 February 15, {Pages 247-258 }

Abstract

Nonlinear behavior of an initially curved fully clamped microbeam is investigated in this paper. The microbeam is laminated between two thin piezoelectric layers along its length. Applying voltage to the piezoelectric layers induces a lengthwise force in the microbeam which, in turn, changes the initial rise and the bending stiffness of the microbeam. This feature is used to tune the frequency and the bistability band of the initially curved microbeam for the first time in this paper. The microbeam is electrostatically actuated as well. The governing equation of motion is obtained, using the Hamilton’s principle and the size effect is considered in the formulation of the problem utilizing the strain gradient theory. Static response of the

Risk Factors of Idiopathic Language Development Disorders in Children

JAFAR NASIRI, MOHAMADREZA GHAZAVI, OMID YAGHINI, Sobhan Poormasjedi, KEYVAN GHADIMI, Mohammad Farid Masaeli
Journal Paper , Volume 5 , Issue 217, 2019 January 1, {Pages 66-72 }

Abstract

Background: Language Development Disorders (LDD) is a common idiopathic impairment in children. Numerous risk factors play a role in the emergence of this disorder. Objectives: The present study aimed to examine risk factors of LDD in children aged two to five years. Materials & Methods: In this case-control study, 98 children (aged two to five years) with LDD and 98 children without LDD were selected as case and control groups, respectively. Research population comprised children with language development disorder diagnosed by a pediatric neurologist, and the control group consisted of children without this disorder. Risk factors affecting LDD were examined in both groups, and the two groups were compared using Chi-squared and independent

The efficacy and safety of levetiracetam in the prophylaxis of migraine headaches in children–a randomised trial

Mohammadreza Ghazavi, Gholamreza Jelodar, Omid Yaghini, Jafar Nasiri, Saeid Sadeghian, Reza Azizi Malamiri
Journal PaperPediatria Polska-Polish Journal of Paediatrics , Volume 94 , Issue 3, 2019 January , {Pages 145-150 }

Abstract

ResultsWe enrolled 66 children with migraine, and 60 of them completed the study (30 in each arm). Ninety per cent (27/30) of children in each arm showed more than 50% reduction in monthly headache frequency. Duration and severity of headaches were also significantly decreased at the end of the trial. In addition, the safety profile of medications was acceptable, and headache disability score was significantly improved at the end of the trial.ConclusionsThese results indicate that levetiracetam might be effective and safe in the prophylaxis of migraine headaches in children. It deserves to be considered in the prophylaxis of migraine headaches in children.

On the numerical investigation of size and surface effects on nonlinear dynamics of a nanoresonator under electrostatic actuation

Sasan Rahmanian, Mohammad-Reza Ghazavi, Shahrokh Hosseini-Hashemi
Journal PaperJournal of the Brazilian Society of Mechanical Sciences and Engineering , Volume 41 , Issue 1, 2019 January 1, {Pages 16 }

Abstract

This study aims to investigate the influences of nanostructure parameter and surface elasticity parameters on the nonlinear vibration of a nanoelectromechanical system under double-sided electrostatic actuation. For this, the effects of size dependency and surface energy are modeled through applying the consistent couple-stress theory together with the Gurtin–Murdoch elasticity theory. Taking into account the midplane stretching effect for doubly clamped boundary conditions, the nonlinear strain–displacement relationship is considered based on the Euler–Bernoulli beam assumption. Hamilton’s principle is utilized in order to establish the governing differential motion’s equation, and reduced-order model is obtained t

Therapeutic Effects of Single and Divided Doses of Piracetam for Children with Severe Breath Holding Spells

Jafar Nasiri, Akbar Azimi, Mohammadreza Ghazavi, Mortaza Sadinejad
Journal PaperJournal of Comprehensive Pediatrics , Volume 10 , Issue 4, 2019 November 30, {Pages }

Abstract

Objectives: Breath-holding spells (BHS) are common in infancy and childhood. The severe episodes are frightening events for the families. The aim of this study was to evaluate therapeutic effects of piracetam in single daily dose and twice-daily dose of 40 mg/kg/day for treatment of severe spells.Methods: In this prospective clinical trial, 50 children with severe BHS referred to our outpatient university clinics of pediatric neurology and were randomized to single-dose and divided-dose groups. The single-dose group received a single daily dose of 40 mg/kg/day piracetam in the morning, and the divided-dose group received 20 mg/kg/dose of piracetam twice daily. Patients were followed for four months. The number of severe attacks/month before

Modeling and Analysis of Rotary Mechanical Systems Linked Through a U-joint

Masoud SoltanRezaee, Mohammad-Reza Ghazavi, Asghar Najafi, Wei-Hsin Liao
Journal PaperInternational Journal of Mechanical Engineering and Robotics Research , Volume 8 , Issue 3, 2019 May , {Pages }

Abstract

Utilizing the U-joint is the most usual and familiar way to connect rotating shafts, which are at an angle with each other. Although, this mechanical coupling has various advantages, converts a constant input velocity to a fluctuating output one. Consequently, this produces resonance conditions in the power transmission system of vehicles. In this study, the vibrations of drivetrains are considered to examine the system torsional behaviors. Here, the derived mathematical model is investigated by means of Floquet theory. Furthermore, the acquired results are validated analytically by applying the frequency analysis. In order to examine the influence of different parameters on the vibrations, the unstable zones are identified and analyzed. In

Risk Factors of Idiopathic Language Development Disorders in Children

Jafar Nasiri, Mohammadreza Ghazavi, Omid Yaghini, Sobhan Poormasjedi, Keyvan Ghadimi, Mohammad Farid Masaeli
Journal PaperCaspian Journal of Neurological Sciences , Volume 5 , Issue 2, 2019 May 10, {Pages 66-72 }

Abstract

Background: Language Development Disorders (LDD) is a common idiopathic impairment in children. Numerous risk factors play a role in the emergence of this disorder.Objectives: The present study aimed to examine risk factors of LDD in children aged two to five years.Materials & Methods: In this case-control study, 98 children (aged two to five years) with LDD and 98 children without LDD were selected as case and control groups, respectively. Research population comprised children with language development disorder diagnosed by a pediatric neurologist, and the control group consisted of children without this disorder. Risk factors affecting LDD were examined in both groups, and the two groups were compared using Chi-squared and independent sa

Stability of a multi-body driveshaft system excited through U-joints

Masoud SoltanRezaee, Mohammad-Reza Ghazavi, Asghar Najafi, Sasan Rahmanian
Journal PaperMeccanica , Volume 53 , Issue 05-Apr, 2018 March 1, {Pages 1167-1183 }

Abstract

The disk-shaft system is a power transmission system with several industrial applications. The shafts, depending on the mechanism application, can be connected by U-joints through different rotating axes. In spite of the many advantages, these joints transform a constant rotating speed into a variable output one. Therefore, the multi-body system is self-excited that lead to dynamic instability. Here, a driveline system including three elastic shafts, which carry three disks, is considered. The oscillating behavior and resonance phenomenon of this fluctuating mechanism are investigated qualitatively and quantitatively. The angle of joints, damping and stiffness effects are the major topics of the present contribution. Eventual

Current Teaching

  • MS.c.

    Metal Cutting

  • MS.c.

    Design of Advanced Mechanisms

Teaching History

  • MS.c.

    Advanced Dynamics

  • MS.c.

    Basic Topics in Mechanical Engineering

  • 2014
    Mohammadi, Hamid reza
    Dynamic analysis of single row ball bearings under the surface wavines
  • 2018
    Najafi Norozmahalle, Pezhman
  • 2019
    Mohammadi Alashti, Shayan
  • 2019
    Motaei, Somayeh
  • 2016
    Vesal, Mohammad Amin
    Stability analysis of a nonlinear blade disc system with imbalance mass by numerical and approximate methods

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