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Muscle synergies based on a biomechanical biaxial isometric shoulder model minimizing fatigue
, Article ASME 2010 10th Biennial Conference on Engineering Systems Design and Analysis, ESDA2010, 12 July 2010 through 14 July 2010 ; Volume 1 , 2010 , Pages 797-804 ; 9780791849156 (ISBN) ; Aminian, K ; Asghari, M ; Parnianpour, M ; Sharif University of Technology
2010
Abstract
In this study we utilize the concept of synergy formation as a simplifying control strategy to manage the high number of degrees of freedom presented in the maintenance of the posture of the shoulder joint. We address how to find the muscle synergy recruitment map to the biomechanical demands (biaxial external torque) during an isometric shoulder task. We use a numerical optimization based shoulder model to obtain muscle activation levels when a biaxial external isometric torque is exposed at the shoulder glenohumeral joint. In the numerical simulations, different shoulder torque vectors parallel to the horizontal plane are considered. For each selected direction for the torque, the...
A Biomechanical Model for Evaluation of Shoulder Function: Detecting the
Relationship Between Muscles Activation Patterns and Shoulder Joint Torques Using Synergy Concept
,
M.Sc. Thesis
Sharif University of Technology
;
Parnianpour, Mohamad
(Supervisor)
;
Asghari, Mohsen
(Supervisor)
Abstract
The effects of combined task demands on the way muscles are recruited to balance external loads during posture and movement is of great importance in quantitative analysis of upper arm function. Pain and disability of shoulder joint is becoming more important as population spends more often interacting with computers in seated position and carrying repetitive tasks using upper extremities. Shoulder joint that is more dependent on the muscles for its normal function than other joints such as hip due to its small articular surface and large range motion has been used here to study its coordination during isometric exertions. Since, the numbers of tasks that could be performed are enormous. In...
How does the central nervous system address the kinetic redundancy in the lumbar spine? Three-dimensional isometric exertions with 18 Hill-model-based muscle fascicles at the L4-L5 level
, Article Proceedings of the Institution of Mechanical Engineers, Part H: Journal of Engineering in Medicine ; Volume 224, Issue 3 , 2010 , Pages 487-501 ; 09544119 (ISSN) ; Khalaf, K ; Nassajian, M. R ; Nasseroleslami, B ; Parnianpour, M ; Sharif University of Technology
2010
Abstract
The human motor system is organized for execution of various motor tasks in a different and flexible manner. The kinetic redundancy in the human musculoskeletal system is a significant property by which the central nervous system achieves many complementary goals. An equilibrium-based biomechanical model of isometric three-dimensional exertions of trunk muscles has been developed. Following the definition and role of the uncontrolled manifold, the kinetic redundancy concept is explored in mathematical terms. The null space of the kinetically redundant system when a certain joint moment and/or stiffness are needed is derived and discussed. The aforementioned concepts have been illustrated,...
Ezafe Recognition Using Dependency Parsing
, M.Sc. Thesis Sharif University of Technology ; Bahrani, Mohammad (Supervisor) ; Shojaei, Razieh (Co-Supervisor)
Abstract
Ezafe is regarded as one of the most controversial and challenging issues in different Persian Language Processing (NLP) fields. It is recognized and pronounced but usually not written. So, this results in a high degree of ambiguity in Persian texts. Dependency grammar plays a significant role in optimization problems. So, to recognize the position of Ezafe in a sentence, this grammar is used in this current study. This method helps speed up computer operations and use low memory. Within this framework, first we take a close look at Ezafe distribution in Persian text. We use Uppsala Persian Dependency Corpus (2015) to analyze parsed sentences. The Ezafe constructions under study include...
A novel cyber-secure algorithm in cooperative vehicles platoon
, Article 2023 9th International Conference on Control, Instrumentation and Automation, ICCIA 2023 ; 2023 ; 979-835036601-3 (ISBN) ; Haeri, M ; Sharif University of Technology
Institute of Electrical and Electronics Engineers Inc
2023
Abstract
This paper studies the problem of secure and resilient distributed cooperative control for autonomous vehicles under false data injection attacks on the vehicular communication net-work. We propose a model-based scheme to detect unknown data falsification attacks using the predicted traj ectory in a distributed nonlinear model predictive control problem. First, as a local agent, each autonomous vehicle stores the information received from its neighboring vehicles to clarify anomalies. The recorded data is investigated over a temporal moving observation window which contains different prediction sequences of the distributed nonlinear model predictive control problem in the previous times. In...
Rotary magnetohydrodynamic micropump based on slug trapping valve
, Article Journal of Microelectromechanical Systems ; Volume 20, Issue 1 , December , 2011 , Pages 260-269 ; 10577157 (ISSN) ; Shafii, M. B ; Sharif University of Technology
2011
Abstract
A novel rotary magnetohydrodynamic (MHD) (RMHD) micropump is presented in this paper in order to both benefit exclusive advantages from the MHD micropumps and eliminate the current obstacles in their implementation. Lorentz force, which is the actuation mechanism in RMHD, is used to propel a mercury slug in a circular microchannel in order to suck the working fluid from the inlet and pump it to the outlet. This idea is integrated with a valve which prevents the working fluid from passing through, while allowing the mercury slug to pass, during each pumping loop. The performance of a fabricated RMHD is evaluated, considering parameters such as pressure difference, running duration, electric...
Dynamic lane changing control of vehicle platoon
, Article 2023 31st International Conference on Electrical Engineering, ICEE 2023 ; 2023 , Pages 432-436 ; 979-835031256-0 (ISBN) ; Haeri, M ; Sharif University of Technology
Institute of Electrical and Electronics Engineers Inc
2023
Abstract
In this paper, a cooperative approach for control heterogeneous connected and autonomous vehicles (CAVs) platoon considering lane-change maneuvers is proposed. In complex dynamic traffic environment, the speed of the surrounding vehicles of CAVs changes dynamically. Thus, the lane changing vehicle requires considering velocity fluctuations to achieve safe driving. The aim of this study is to combine dynamic path planning based on a cubic curve and model predictive control (MPC) with collision avoidance constraint to track an optimally generated path. The proposed control performs as a maneuver switching model including the vehicle's continuous states and discrete maneuver transition rule for...
How well do the muscular synergies extracted via non-negative matrix factorisation explain the variation of torque at shoulder joint?
, Article Computer Methods in Biomechanics and Biomedical Engineering ; Volume 16, Issue 3 , 2013 , Pages 291-301 ; 10255842 (ISSN) ; Aminian, K ; Asghari, M ; Parnianpour, M ; Sharif University of Technology
2013
Abstract
The way central nervous system manages the excess degrees of freedom to solve kinetic redundancy of musculoskeletal system remains an open question. In this study, we utilise the concept of synergy formation as a simplifying control strategy to find the muscle recruitment based on summation of identified muscle synergies to balance the biomechanical demands (biaxial external torque) during an isometric shoulder task. A numerical optimisation-based shoulder model was used to obtain muscle activation levels when a biaxial external isometric torque is imposed at the shoulder glenohumeral joint. In the numerical simulations, 12 different shoulder torque vectors in the transverse plane are...
Acidic derivatives of melamine as template in copolymerization of aniline and metanilic acid
, Article Polymer - Plastics Technology and Engineering ; 2017 , Pages 1-10 ; 03602559 (ISSN) ; Najafi Moghadam, P ; Hashemi, M. M ; Sharif University of Technology
2017
Abstract
In this paper, new polymer composites were synthesized by template copolymerization of aniline and metanilic acid in the presence of prepared melamine triacetic acid and poly(melamine-co-citric acid) as polyacids and dopants. The properties of the poly(aniline-co-metanilic acid) composites were studied by Fourier transform infrared, X-ray diffraction, scanning electron microscope, CV, and differential scanning calorimeter analysis. The four-point probe technique was used for evaluating the electrical conductivity of the composites. The scanning electron micrographs disclosed that the products had the morphology with agglomerated distorted spherical shapes with the average size of 40–50 nm....
Acidic derivatives of melamine as template in copolymerization of aniline and metanilic acid
, Article Polymer - Plastics Technology and Engineering ; Volume 57, Issue 10 , 2018 , Pages 965-974 ; 03602559 (ISSN) ; Najafi Moghadam, P ; Hashemi, M. M ; Sharif University of Technology
Taylor and Francis Inc
2018
Abstract
In this paper, new polymer composites were synthesized by template copolymerization of aniline and metanilic acid in the presence of prepared melamine triacetic acid and poly(melamine-co-citric acid) as polyacids and dopants. The properties of the poly(aniline-co-metanilic acid) composites were studied by Fourier transform infrared, X-ray diffraction, scanning electron microscope, CV, and differential scanning calorimeter analysis. The four-point probe technique was used for evaluating the electrical conductivity of the composites. The scanning electron micrographs disclosed that the products had the morphology with agglomerated distorted spherical shapes with the average size of 40–50 nm....
Sensorless control of PMSMs with tolerance for delays and stator resistance uncertainties
, Article IEEE Transactions on Power Electronics ; Volume 28, Issue 3 , 2013 , Pages 1391-1399 ; 08858993 (ISSN) ; Tahami, F ; Sharif University of Technology
2013
Abstract
Position sensorless control of ac machines at zero and low speed is possible using high-frequency carrier injection methods. These methods utilize anisotropic properties of rotor. Therefore, they may lose their efficiency for nonsalient machines or machines with small rotor saliency. In these machines, measurement noise and offset, existing delays, as well as model uncertainties may lead to inaccurate estimation of rotor position. Stator resistance which is usually neglected in these methods may also lead to a considerable error especially in machines with small rotor saliency. In this paper, a new position estimation method is presented, and it is shown that in comparison to conventional...
Evaluation of PR steel frame connection with torsional plate and its optimal placement
, Article Scientia Iranica ; Volume 25, Issue 3A , 2018 , Pages 1025-1038 ; 10263098 (ISSN) ; Estekanchi, H.E ; Yekrangnia, M ; Sharif University of Technology
Sharif University of Technology
2018
Abstract
Characteristics of connections in steel moment-resisting frames are of utmost importance in determining the seismic performance of these structural systems. The results of several previous experimental studies have indicated that Partially Restrained (PR) connections possess excellent properties, which make them a reliable substitution for Fully Restrained (FR) connections. These properties include needing less base shear, being more economic, and, in many cases, being able to absorb more energy. In this study, the behavior of two proposed PR connections with torsional plate is studied through finite element simulations. The results of the numerical studies regarding initial stiffness and...
Catalyst-Free and Green Synthesis of Some Novel Benzamide Derivatives
, Article Journal of Heterocyclic Chemistry ; Volume 52, Issue 6 , November , 2015 , Pages 1848-1857 ; 0022152X (ISSN) ; Rostami, M ; Mirkhani, V ; Moghadam, M ; Mohammadpoor Baltork, I ; Tangestaninejad, S ; Jamali Moghadam, A ; Kia, R ; Sharif University of Technology
HeteroCorporation
2015
Abstract
In the present work, a simple, green, rapid, and catalyst-free procedure for the synthesis of benzamide derivatives by ring opening of azlactones with diamines such as ethylene diamine and 1,3-propylenediamine is described. The present method offers several advantages such as short reaction times, easy work-up, and mild reaction conditions in the absence of catalyst and any toxic solvent and material. In addition, the structure obtained by X-ray crystallography was compared with the theoretical results obtained by density functional theory using the B3LYP functional and cc-pVDZ basis sets
Bistatic ambiguity function and DOA estimation for PCL radar
, Article APCCAS 2006 - 2006 IEEE Asia Pacific Conference on Circuits and Systems, 4 December 2006 through 6 December 2006 ; 2006 , Pages 840-843 ; 1424403871 (ISBN); 9781424403875 (ISBN) ; Jafargholi, A ; Emadi, M ; Nayebi, M. M ; Sharif University of Technology
2006
Abstract
in this paper detection and the accuracy of measurement of range, velocity and DOA in PCL radar for optimized parameters is considered. It is shown that, in order to measure the bistatic characteristics of a target, we can process the monostatic ambiguity function and extract the bistatic factors by proposed Algorithm. ©2006 IEEE
Towards greater mechanical, thermal and chemical stability in solid-phase microextraction
, Article TrAC - Trends in Analytical Chemistry ; Volume 34 , 2012 , Pages 126-138 ; 01659936 (ISSN) ; Piri-Moghadam, H ; Naderi, M ; Sharif University of Technology
2012
Abstract
Solid-phase microextraction (SPME) is a fast, solvent-free technique, which, since its introduction in the 1990s, has been increasingly applied to sample preparation in analytical chemistry. Conventional SPME fibers are fabricated by making a physical bond between the usual silica substrate and the polymeric coatings. However, some applications are limited, as the lifetime and the stability of conventional SPME fibers cannot meet the demands of analyzing relatively non-volatile compounds with more polar moieties. There have been attempts to analyze less volatile compounds by increasing the thermal, physical and chemical stability of the fibers. In this review, we present some new...
Timetable optimization for maximum usage of regenerative energy of braking in electrical railway systems
, Article SPEEDAM 2010 - International Symposium on Power Electronics, Electrical Drives, Automation and Motion, 14 June 2010 through 16 June 2010 ; June , 2010 , Pages 1218-1221 ; 9781424449873 (ISBN) ; Fekri Moghadam, M ; Mokhtari, H ; Sharif University of Technology
2010
Abstract
Research projects in urban transportation systems require proper simulation softwares. Such softwares are the basic requirements of any kind of study in electrical transportation systems. Due to high energy consumption of these systems, studies for its optimization are challenging and necessary. In this paper an optimized timetable of trains? movement is proposed in order to completely utilize the regenerative energy of trains? braking in stations. A sample subway system is simulated and Genetic algorithm is used as an optimization method. The effect of headway and reserve times on the amount of energy consumption is studied and an optimized reserve time set is found for the sample system....
A robust simulation optimization algorithm using kriging and particle swarm optimization: application to surgery room optimization
, Article Communications in Statistics: Simulation and Computation ; 2019 ; 03610918 (ISSN) ; Seifi, F ; Moghadam, S ; Sharif University of Technology
Taylor and Francis Inc
2019
Abstract
Simulation optimization is an endeavor to determine the best combination of inputs that result in the best system performance criterion without evaluating all possible combinations. Since simulation optimization applies to many problems, it is extensively studied in the literature with different methods. However, most of these methods ignore the uncertainty of the systems’ parameters, which may lead to a solution that is not robustly optimal in reality. Motivated by this uncertainty, we propose a robust simulation optimization algorithm that follows the well-known Taguchi standpoint but replaces its statistical technique with a minimax method based on the kriging (Gaussian process)...
Self-powered wearable piezoelectric sensors based on polymer nanofiber-metal-organic framework nanoparticle composites for arterial pulse monitoring
, Article ACS Applied Nano Materials ; Volume 3, Issue 9 , August , 2020 , Pages 8742-8752 ; Hasanzadeh, M ; Simchi, A ; Sharif University of Technology
American Chemical Society
2020
Abstract
High-performance wearable electronic devices with the capability of converting mechanical force into electrical energy have been gaining increasing attention for biomedical monitoring applications. We present a novel wearable piezoelectric sensor based on a poly(vinylidene fluoride) (PVDF) nanofibrous membrane containing microporous zirconium-based metal-organic frameworks (MOFs) for arterial pulse monitoring. It is shown that the incorporation of 5 wt % of MOF greatly enhances the piezoelectric constant of the polymer fibrous mat by 3.4-fold without significant loss in its flexibility. The nanofibrous composite exhibits a peak-to-peak voltage of 600 mV under an applied force of 5 N, which...
A robust simulation optimization algorithm using kriging and particle swarm optimization: Application to surgery room optimization
, Article Communications in Statistics: Simulation and Computation ; 2019 ; 03610918 (ISSN) ; Seifi, F ; Moghadam, S ; Sharif University of Technology
Taylor and Francis Inc
2019
Abstract
Simulation optimization is an endeavor to determine the best combination of inputs that result in the best system performance criterion without evaluating all possible combinations. Since simulation optimization applies to many problems, it is extensively studied in the literature with different methods. However, most of these methods ignore the uncertainty of the systems’ parameters, which may lead to a solution that is not robustly optimal in reality. Motivated by this uncertainty, we propose a robust simulation optimization algorithm that follows the well-known Taguchi standpoint but replaces its statistical technique with a minimax method based on the kriging (Gaussian process)...
Deriving an analytical model for hydro-magnetic micro flow controller
, Article 6th International Conference on Nanochannels, Microchannels, and Minichannels, ICNMM2008, Darmstadt, 23 June 2008 through 25 June 2008 ; Issue PART B , June , 2008 , Pages 1139-1146 ; 0791848345 (ISBN); 9780791848340 (ISBN) ; Shafii, M. B ; ASME ; Sharif University of Technology
2008
Abstract
Fluid control, namely pumping and valving, is a critical factor in the performance of micro-fluidic systems. In recent years a variety of micro-fluidic systems are developed for the purpose of miniaturizing fluid handling, and chemical analysis to develop Lab On a Chip (LOC) technology. The mentioned facts resulted in design and fabrication of a novel hydromagnetic flow controller. The idea behind this device is that magnetic particles, mixed and dispersed in a carrier liquid, can be accumulated in the form of a piston. Depending upon dragging speed of these pistons, which itself is a function of switching time, this device can be used to either increase (pumping) or decrease (valving) the...