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    Comment on S. Ahmed, H. Wang, and Y. Tian, “Robust adaptive fractional-order terminal sliding mode control for lower-limb exoskeleton,” Asian J. Control, vol. 21, no. 1, pp. 1–10 (2019)

    , Article Asian Journal of Control ; 2022 ; 15618625 (ISSN) Samaei, M. H ; Sheikh Ahmadi, S ; Naderi Soorki, M ; Amini, S. S ; Sharif University of Technology
    John Wiley and Sons Inc  2022
    Abstract
    In this comment, it is shown that there are some non-negligible big mistakes in the analyses and stability proof of the proposed controller in the quoted paper, which makes the main results of this paper to be incorrect. The main unavoidable mistakes in the stability analysis of the main theorem (Theorem 1) are stated and some remarks are also mentioned to fix some of them. © 2022 Chinese Automatic Control Society and John Wiley & Sons Australia, Ltd  

    Graphene-based nanomaterials in fighting the most challenging viruses and immunogenic disorders

    , Article ACS Biomaterials Science and Engineering ; Volume 8, Issue 1 , 2022 , Pages 54-81 ; 23739878 (ISSN) Ebrahimi, M ; Asadi, M ; Akhavan, O ; Sharif University of Technology
    American Chemical Society  2022
    Abstract
    Viral diseases have long been among the biggest challenges for healthcare systems around the world. The recent Coronavirus Disease 2019 (COVID-19) pandemic is an example of how complicated the situation can get if we are not prepared to combat a viral outbreak in time, which brings up the need for quick and affordable biosensing platforms and vast knowledge of potential antiviral effects and drug/gene delivery opportunities. The same challenges have also existed for nonviral immunogenic disorders. Nanomedicine is considered a novel candidate for effectively overcoming these worldwide challenges. Among the versatile nanomaterials commonly used in biomedical applications, graphene has recently... 

    Conformation- and phosphorylation-dependent electron tunnelling across self-assembled monolayers of tau peptides

    , Article Journal of Colloid and Interface Science ; Volume 606 , 2022 , Pages 2038-2050 ; 00219797 (ISSN) Ashkarran, A. A ; Hosseini, A ; Loloee, R ; Perry, G ; Lee, K. B ; Lund, M ; Ejtehadi, M. R ; Mahmoudi, M ; Sharif University of Technology
    Academic Press Inc  2022
    Abstract
    We report on charge transport across self-assembled monolayers (SAMs) of short tau peptides by probing the electron tunneling rates and quantum mechanical simulation. We measured the electron tunneling rates across SAMs of carboxyl-terminated linker molecules (C6H12O2S) and short cis-tau (CT) and trans-tau (TT) peptides, supported on template-stripped gold (AuTS) bottom electrode, with Eutectic Gallium-Indium (EGaIn)(EGaIn) top electrode. Measurements of the current density across thousands of AuTS/linker/tau//Ga2O3/EGaIn single-molecule junctions show that the tunneling current across CT peptide is one order of magnitude lower than that of TT peptide. Quantum mechanical simulation... 

    Effect of the heteroatom presence in different positions of the model asphaltene structure on the self-aggregation: MD and DFT study

    , Article Journal of Molecular Liquids ; Volume 334 , 2021 ; 01677322 (ISSN) Ekramipooya, A ; Mirzaee Valadi, F ; Farisabadi, A ; Gholami, M. R ; Sharif University of Technology
    Elsevier B.V  2021
    Abstract
    In this study, a series of heteroatoms including nitrogen, oxygen, and sulfur were added to different positions of the model asphaltene structure to study the effect of the heteroatom presence in the self-aggregation of the model asphaltenes. Molecular Dynamics was used to calculate Solubility Parameters, Radial Distribution Function, and Relative Solubility Parameters. Additionally, Reactivity Parameters, Electrostatic Potential, Reduced Density Gradient, and Independent Gradient Model were calculated using the Density Functional Theory to further investigate the Molecular Dynamics results. This study indicated that heteroatoms' diversity and their positions in the model asphaltene... 

    PBN-Based time-optimal terminal air traffic control using cellular automata

    , Article IEEE Transactions on Aerospace and Electronic Systems ; Volume 57, Issue 3 , 2021 , Pages 1513-1523 ; 00189251 (ISSN) Enayatollahi, F ; Amiri Atashgah, M. A ; Malaek, S. M. B ; Thulasiraman, P ; Sharif University of Technology
    Institute of Electrical and Electronics Engineers Inc  2021
    Abstract
    Over the last decade, there has been an increase in air transportation, which has raised awareness to provide necessary procedures to respond to air transportation demands and reduce delay costs. One such procedure, 'performance-based navigation (PBN),' currently studied, is expected to increase the airspace capacity based on aircraft's individual performances. This research describes an efficient and expandable model for allocating standard terminal arrival route during continuous descent approach (CDA) that effectively uses PBN requirements. As a case study, we have considered the 'Atlanta International Airport' and verified the model's accuracy using real-time traffic data. The model is... 

    Design of a continuous fractional-order nonsingular terminal sliding mode control with time delay estimation for fes control of human knee joint

    , Article 7th International Conference on Control, Instrumentation and Automation, ICCIA 2021, 23 February 2021 through 24 February 2021 ; 2021 ; 9780738124056 (ISBN) Karami, M ; Abbasi, M ; Vossoughi, G ; Sharif University of Technology
    Institute of Electrical and Electronics Engineers Inc  2021
    Abstract
    The design of a novel Continuous Fractional-Order Nonsingular Terminal Sliding Mode controller is the focus of this study. Time Delay Estimation technique is incorporated into the controller. The proposed method is responsible for controlling the human knee joint neuromusculoskeletal model via Functional Electrical Stimulation. A second-order nonlinear model with time-varying coefficients is used for characterizing the FES-stimulated neuromusculoskeletal model. The presence of time-varying coefficients often complicates precise control of knee joint through FES and impairs the performance of conventional methods. To this end, the TDECFONTSM has been proposed consisting of three components, a... 

    ST-CAC: a low-cost crosstalk avoidance coding mechanism based on three-valued numerical system

    , Article Journal of Supercomputing ; Volume 77, Issue 7 , 2021 , Pages 6692-6713 ; 09208542 (ISSN) Shirmohammadi, Z ; Khorami, A ; Omana, M. E ; Sharif University of Technology
    Springer  2021
    Abstract
    Appearances of specific transition patterns during data transfer in bus lines of modern high-performance computing systems, such as communicating structures of accelerators for deep convolutional neural networks, commercial Network on Chips, and memories, can lead to crosstalk faults. With the shrinkage of technology size, crosstalk faults occurrence boosts and leads to degradation of reliability and performance, as well as the increasing power consumption of lines. One effective way to alleviate crosstalk faults is to avoid the appearance of these specific transition patterns by using numerical-based crosstalk avoidance codes (CACs). However, a serious problem with numerical-based CACs is... 

    Nonsingular terminal sliding mode control with ultra-local model and single input interval type-2 fuzzy logic control for pitch control of wind turbines

    , Article IEEE/CAA Journal of Automatica Sinica ; Volume 8, Issue 3 , 2021 , Pages 690-700 ; 23299266 (ISSN) Abrazeh, S ; Parvaresh, A ; Mohseni, S. R ; Jahanshahi Zeitouni, M ; Gheisarnejad, M ; Khooban, M. H ; Sharif University of Technology
    Institute of Electrical and Electronics Engineers Inc  2021
    Abstract
    As wind energy is becoming one of the fastest-growing renewable energy resources, controlling large-scale wind turbines remains a challenging task due to its system model nonlinearities and high external uncertainties. The main goal of the current work is to propose an intelligent control of the wind turbine system without the need for model identification. For this purpose, a novel model-independent nonsingular terminal sliding-mode control (MINTSMC) using the basic principles of the ultra-local model (ULM) and combined with the single input interval type-2 fuzzy logic control (SIT2-FLC) is developed for non-linear wind turbine pitch angle control. In the suggested control framework, the... 

    Nonsingular terminal sliding mode control with ultra-local model and single input interval type-2 fuzzy logic control for pitch control of wind turbines

    , Article IEEE/CAA Journal of Automatica Sinica ; Volume 8, Issue 3 , 2021 , Pages 690-700 ; 23299266 (ISSN) Abrazeh, S ; Parvaresh, A ; Mohseni, S. R ; Zeitouni, M. J ; Gheisarnejad, M ; Khooban, M. H ; Sharif University of Technology
    Institute of Electrical and Electronics Engineers Inc  2021
    Abstract
    As wind energy is becoming one of the fastest-growing renewable energy resources, controlling large-scale wind turbines remains a challenging task due to its system model nonlinearities and high external uncertainties. The main goal of the current work is to propose an intelligent control of the wind turbine system without the need for model identification. For this purpose, a novel model-independent nonsingular terminal sliding-mode control (MINTSMC) using the basic principles of the ultra-local model (ULM) and combined with the single input interval type-2 fuzzy logic control (SIT2-FLC) is developed for non-linear wind turbine pitch angle control. In the suggested control framework, the... 

    A novel copper-catalyzed synthesis of n-monosubstituted 2-alkynimi-damides from 1-alkynes and trichloroacetamidines

    , Article Letters in Organic Chemistry ; Volume 17, Issue 9 , 2020 , Pages 704-708 Fasihi Dastjerdi, H ; Nematpour, M ; Rezaee, E ; Jahani, M ; Tabatabai, S. A ; Sharif University of Technology
    Bentham Science Publishers  2020
    Abstract
    A one-pot Cu-catalyzed synthesis of functionalized alkynyl imidamide by terminal alkynes, trichloroacetonitrile and aniline or benzyl amine is reported. The compounds were produced via coupling reaction of terminal alkynes with trichloroacetamidine. This method was performed under mild, ligand-free conditions and easy work-up method. © 2020, Bentham Science Publishers. All rights reserved  

    Distributed voting in beep model

    , Article Signal Processing ; Volume 177 , 2020 Ghojogh, B ; Salehkaleybar, S ; Sharif University of Technology
    Elsevier B.V  2020
    Abstract
    We consider the problem of distributed multi-choice voting in a setting that each node can communicate with its neighbors merely by sending beep signals. Given its simplicity, the beep communication model is of practical importance in different applications such as system biology and wireless sensor networks. Yet, the distributed majority voting has not been resolved in this setting. In this paper, we propose two algorithms, named Distributed Voting with Beeps, to resolve this problem. In the first proposed algorithm, the adjacent nodes having the same value form a set called spot. Afterwards, the spots with majority value try to corrode the spots with non-majority values. The second... 

    Design of peptide-based inhibitor agent against amyloid-β aggregation: Molecular docking, synthesis and in vitro evaluation

    , Article Bioorganic Chemistry ; Volume 102 , September , 2020 Jokar, S ; Erfani, M ; Bavi, O ; Khazaei, S ; Sharifzadeh, M ; Hajiramezanali, M ; Beiki, D ; Shamloo, A ; Sharif University of Technology
    Academic Press Inc  2020
    Abstract
    Formation of the amyloid beta (Aβ) peptide aggregations represents an indispensable role in appearing and progression of Alzheimer disease. β-sheet breaker peptides can be designed and modified with different amino acids in order to improve biological properties and binding affinity to the amyloid beta peptide. In the present study, three peptide sequences were designed based on the hopeful results of LIAIMA peptide and molecular docking studies were carried out onto the monomer and fibril structure of amyloid beta peptide using AutoDock Vina software. According to the obtained interactions and binding energy from docking, the best-designed peptide (D-GABA-FPLIAIMA) was chosen and... 

    Closed-loop powered-coast-powered predictive guidance for spacecraft rendezvous with non-singular terminal sliding mode steering

    , Article Acta Astronautica ; Volume 166 , 2020 , Pages 507-523 Kasaeian, S. A ; Ebrahimi, M ; Assadian, N ; Sharif University of Technology
    Elsevier Ltd  2020
    Abstract
    The present study aims to present a guidance algorithm based on the relative motion prediction for orbital rendezvous, in which a coast phase is allowed between two powered phases. In both powered phases, the solution of the Hill-Clohessy-Wiltshire equations is used to find the required state variables at each time instant. To track the required trajectory and compensate for any orbital perturbations and uncertainties, a non-singular terminal sliding mode method is utilized as the steering law. Then, the finite time convergence of the state variables is mathematically proved. In addition, the starting time of the second powered phase is adapted to perturbations and uncertainties by another... 

    A 3D path planning algorithm based on PSO for autonomous UAVs navigation

    , Article 9th International Conference on Bioinspired Optimization Methods and Their Applications, BIOMA 2020, 19 November 2020 through 20 November 2020 ; Volume 12438 LNCS , 2020 , Pages 268-280 Mirshamsi, A ; Godio, S ; Nobakhti, A ; Primatesta, S ; Dovis, F ; Guglieri, G ; Sharif University of Technology
    Springer Science and Business Media Deutschland GmbH  2020
    Abstract
    In this paper, a new three-dimensional path planning approach with obstacle avoidance for UAVs is proposed. The aim is to provide a computationally-fast on-board sub-optimal solution for collision-free path planning in static environments. The optimal 3D path is an NP (non-deterministic polynomial-time) hard problem which may be solved numerically by global optimization algorithms such as the Particle Swarm Optimization (PSO). Application of PSO to the 3D path planning class of problems faces typical challenges such slow convergence rate. It is shown that the performance may be improved markedly by implementing a novel parallel approach and incorporation of new termination conditions.... 

    Identification of a novel multifunctional ligand for simultaneous inhibition of amyloid-beta (aβ42) and chelation of zinc metal ion

    , Article ACS Chemical Neuroscience ; Volume 10, Issue 11 , 2019 , Pages 4619-4632 ; 19487193 (ISSN) Asadbegi, M ; Shamloo, A ; Sharif University of Technology
    American Chemical Society  2019
    Abstract
    Zinc binding to β-amyloid structure could promote amyloid-β aggregation, as well as reactive oxygen species (ROS) production, as suggested in many experimental and theoretical studies. Therefore, the introduction of multifunctional drugs capable of chelating zinc metal ion and inhibiting Aβ aggregation is a promising strategy in the development of AD treatment. The present study has evaluated the efficacy of a new bifunctional peptide drug using molecular docking and molecular dynamics (MD) simulations. This drug comprises two different domains, an inhibitor domain, obtained from the C-terminal hydrophobic region of Aβ, and a Zn2+ chelating domain, derived from rapeseed meal, merge with a... 

    An MP-based approximation algorithm on reliability evaluation of multistate flow networks

    , Article Reliability Engineering and System Safety ; Volume 191 , 2019 ; 09518320 (ISSN) Forghani Elahabad, M ; Kagan, N ; Mahdavi Amiri, N ; Sharif University of Technology
    Elsevier Ltd  2019
    Abstract
    In recent decades, multistate two-terminal reliability problem has attracted several researchers, and accordingly many exact and approximation approaches have been proposed in the literature in terms of minimal cuts (MCs) or minimal paths (MPs) to address this problem. Here, an MP-based approximation approach is developed based on exact algorithms. With all the MPs at hand, the approach rearranges the MPs ascendingly with respect to their lengths and then sets the flow on some MPs to be zero which turns to reduce the computing cost in solving the problem. We provide the complexity results, and by employing some benchmarks and one thousand randomly generated networks illustrate that not only... 

    A terminal guidance algorithm based on ant colony optimization

    , Article Computers and Electrical Engineering ; Volume 77 , 2019 , Pages 128-146 ; 00457906 (ISSN) Nobahari, H ; Nasrollahi, S ; Sharif University of Technology
    Elsevier Ltd  2019
    Abstract
    In this paper, terminal engagement of a maneuvering target and a pursuer is investigated. A heuristic nonlinear model predictive guidance algorithm is presented. Nonlinear kinematics of the pursuer and the target is utilized to formulate the guidance problem. Also, the target maneuver is assumed to be unknown. The proposed heuristic guidance algorithm uses an ant-based optimization algorithm to estimate simultaneously the states of the pursuer, the maneuver of the target, and the optimal guidance commands. Performance of the new guidance algorithm against maneuvering and non-maneuvering targets is evaluated using numerical simulations. Also, the results of the guidance algorithm are compared... 

    Investigation of the impact of synthesized hydrophobic magnetite nanoparticles on mass transfer and hydrodynamics of stagnant and stirred liquid–liquid extraction systems

    , Article Chemical Engineering Research and Design ; Volume 147 , 2019 , Pages 305-318 ; 02638762 (ISSN) Hatami, A ; Azizi, Z ; Bastani, D ; Sharif University of Technology
    Institution of Chemical Engineers  2019
    Abstract
    The impact of modified magnetite nanoparticles (MMNPs)on hydrodynamics and mass transfer in liquid–liquid extraction process was assessed using a ternary chemical system of toluene-acetic acid–water. The organic phase which contained toluene and acetic acid was dispersed through water, and the mass transfer of acetic acid between two phases was investigated. The hydrophobic modified magnetite nanoparticles (MMNPs)prepared through an optimized in-situ method were added to the dispersed phase at different concentrations (0.001−0.005 wt%). Two separate conditions were provided in the experiments, i.e. stagnant and stirred continuous phase. The latter case was provided by a rotor at two... 

    Dynamic Gossip

    , Article Bulletin of the Iranian Mathematical Society ; Volume 45, Issue 3 , 2019 , Pages 701-728 ; 10186301 (ISSN) van Ditmarsch, H ; van Eijck, J ; Pardo, P ; Ramezanian, R ; Schwarzentruber, F ; Sharif University of Technology
    Springer International Publishing  2019
    Abstract
    A gossip protocol is a procedure for spreading secrets among a group of agents, using a connection graph. The goal is for all agents to get to know all secrets, in which case we call the execution of the protocol successful. We consider distributed and dynamic gossip protocols. In distributed gossip, the agents themselves instead of a global scheduler determine whom to call. In dynamic gossip, not only secrets are exchanged but also telephone numbers (agent identities). This results in increased graph connectivity. We define six such distributed dynamic gossip protocols, and we characterize them in terms of the topology of the graphs on which they are successful, wherein we distinguish... 

    A reliable and fast response buck converter based on interleaved converter

    , Article 27th Iranian Conference on Electrical Engineering, ICEE 2019, 30 April 2019 through 2 May 2019 ; 2019 , Pages 804-807 ; 9781728115085 (ISBN) Keshtkar Teeula, A ; Kaboli, S ; Sharif University of Technology
    Institute of Electrical and Electronics Engineers Inc  2019
    Abstract
    Power Distribution Unit (PDU) is a power supply unit that supplies various DC voltage levels for electric equipment. Reliability of PDU is very important in electrical systems. Buck converter is frequently used in PDU to provide the lower voltage levels than the source voltage level. The output capacitor of the buck converter is the main factor of failure. In this paper, we present a method to design a buck converter with almost no inductor current ripple. If the inductor current ripple is eliminated, the output capacitor can be removed from the converter. By removing the capacitor, the reliability and transient response of the converter can be improved considerably. The proposed method is...