A method for automatic tuning the memristance of memristive devices with the capacity of applying to memristive memories

, Article 2012 International Conference on Computer Systems and Industrial Informatics, ICCSII 2012, 18 December 2012 through 20 December 2012 ; December , 2012 ; 9781467351577 (ISBN) Merrikh Bayat, F ; Merrikh Bayat, F ; Mirebrahimi, N ; Sharif University of Technology

2012

Abstract

Memristor is the fourth fundamental passive circuit element which has potential applications in development of analog memristive memories, neuroscience, and brain simulation. In all of these applications the memristance of the device should be adjusted to the desired value, which is currently performed by trial and error. The aim of this paper is to propose a new method and develop a circuit for automatic adjustment of the memristance of memristive devices. The proposed method is based on the sliding mode control and numerical simulations show that it can be used for tuning the memristance of such devices with a high accuracy

The neuro-fuzzy computing system with the capacity of implementation on a memristor crossbar and optimization-free hardware training

, Article IEEE Transactions on Fuzzy Systems ; Vol. 22, Issue. 5 , 2014 , Pages 1272-1287 ; ISSN: 10636706 Merrikh-Bayat, F ; Merrikh-Bayat, F ; Shouraki, S. B ; Sharif University of Technology

2014

Abstract

In this paper, first we present a new explanation for the relationship between logical circuits and artificial neural networks, logical circuits and fuzzy logic, and artificial neural networks and fuzzy inference systems. This shows us that neural networks are working in the same way as logical circuits when the connection between them is through the fuzzy logic. However, themain difference between them is that logical circuits can be constructed without using any kind of optimization-based learning methods. Based on these results, we propose a new neuro-fuzzy computing system. As verified by simulation results, it can effectively be implemented on the memristor crossbar structure and...

Memristive fuzzy edge detector

, Article Journal of Real-Time Image Processing ; Vol. 9, issue. 3 , September , 2014 , pp. 479-489 ; Online ISSN: 1861-8219 Merrikh-Bayat, F ; Bagheri Shouraki, S ; Merrikh-Bayat, F ; Sharif University of Technology

2014

Abstract

Fuzzy inference systems always suffer from the lack of efficient structures or platforms for their hardware implementation. In this paper, we tried to overcome this difficulty by proposing a new method for the implementation of the fuzzy rule-based inference systems. To achieve this goal, we have designed a multi-layer neuro-fuzzy computing system based on the memristor crossbar structure by introducing a new concept called the fuzzy minterm. Although many applications can be realized through the use of our proposed system, in this study we only show how the fuzzy XOR function can be constructed and how it can be used to extract edges from grayscale images. One main advantage of our...

Memristor crossbar-based hardware implementation of fuzzy membership functions

, Article Proceedings - 2011 8th International Conference on Fuzzy Systems and Knowledge Discovery, FSKD 2011, 26 July 2011 through 28 July 2011 ; Volume 1 , July , 2011 , Pages 645-649 ; 9781612841816 (ISBN) Merrikh Bayat, F ; Shouraki, S. B ; Merrikh Bayat, F ; Sharif University of Technology

2011

Abstract

In May 1, 2008, researchers at Hewlett Packard (HP) announced the first physical realization of a fundamental circuit element called memristor that attracted so much interest worldwide. This newly found element can easily be combined with crossbar interconnect technology which this new structure has opened a new field in designing configurable or programmable electronic systems. These systems in return can have applications in signal processing and artificial intelligence. In this paper, based on the simple memristor crossbar structure, we propose new and simple circuits for hardware implementation of fuzzy membership functions. In our proposed circuits, these fuzzy membership functions can...

Experimental Study of Drying and Calcination of Simulated High-Level Waste (HLW)

, M.Sc. Thesis Sharif University of Technology Farahzadi, Zahra (Author) ; Samadfam, Mohammad (Supervisor) ; Zahakifar, Fazel (Supervisor) ; Zaheri, Parisa (Co-Supervisor)

Abstract

One of the novel methods of stabilization of nuclear waste is the use of vitrification technology. In order to stabilize high level wastes (HLLW) in glass, it is required that the elements are in their oxide form. Therefore, it is necessary to evaporate the waste and turn it into a solid form so that the elements can be converted into oxide form in the calcination furnace. Hence, one of the challenges of stabilization is the optimization of evaporation and calcination conditions. In this research, the parameters affecting evaporation were first investigated. Using laboratory measurements of application: temperature (110 to 180 °C), presence of nitric acid (0.5 to 4 mol/L), ratio of zirconium...

The Study of Effective Parameters on Thorium Extraction by Cyanex 272 in an Emulsion Liquid Membrane System

, M.Sc. Thesis Sharif University of Technology Ehyaie, Darya (Author) ; Samadfam, Mohammad (Supervisor) ; Zaheri, Parisa (Supervisor) ; Zahakifar, Fazel (Co-Supervisor)

Abstract

This study used the emulsion liquid membrane method to investigate the extraction and separation of thorium from nitrate solution. According to the results obtained from the studies, Cyanex 272 was a suitable option for selectively extracting thorium. For simultaneous extraction and stripping of thorium from dilute aqueous solutions, an emulsion liquid membrane system consisting of Cyanex 272 as an extractant, Span 80 as a surfactant and sulfuric acid solution as a receiving phase (internal phase) was used. Emulsion liquid membrane method has high mass transfer flux due to high surface to volume ratio, which causes high extraction efficiency and fast transfer of thorium ions from its low...

Fabrication Patient-Specific Drill Guide Templates for Cervical Pedicle Screw Placement

, M.Sc. Thesis Sharif University of Technology Safahieh, Amir Hossein (Author) ; Arjmand, Navid (Supervisor) ; Parnianpour, Mohammad (Supervisor) ; Azimi, Parisa (Co-Supervisor)

Abstract

One of the most common spinal surgeries involves spinal fusion or vertebral fixation, which is used to treat various conditions such as intervertebral disc disease, scoliosis (lateral deviation of the spinal column), fractures, infections, or the presence of tumors in the spinal column. In this surgical procedure, the use of pedicle screws and titanium rods prevents motion and friction between two vertebrae. Screws may enter the vertebrae in the wrong position and angle, causing bone weakening, rupture of nerve roots or blood vessels, weakness or lack of sensation in some parts of the body, spinal cord injury, and in severe cases, paralysis of the patient. For this reason, fusion surgery is...

Investigation of Mass Transfer Coefficients in Lithium Liquid-Liquid Extraction Process in Batch and Continuous Modes (Microchannel)

, M.Sc. Thesis Sharif University of Technology Bahadri, Mohammad Mehdi (Author) ; Otokesh, Mohammad (Supervisor) ; Amari Allahyari, Sareh (Supervisor) ; Zaheri, Parisa (Co-Supervisor)

Abstract

Lithium is a soft, silvery-white alkali metal that is recognized as the lightest metal and the least dense solid element. The increasing demand for lithium, driven by the global shift towards electrification and sustainable energy solutions, has transformed this material into a crucial resource in the modern economy. Lithium has applications in various industries, including the nuclear industry. 6Li is used for the production of tritium, and 7Li, in the form of 7LiOH, is used to adjust the pH in light water reactors and as an anti-corrosion compound in fission reactors. In this study, the extraction of lithium from the aqueous phase using a Y-shaped microchannel was carried out, and the mass...

Investigation of the scavenging mechanism of tyrosyl radical by hydroxybenzohydroxamic acid derivatives: A DFT study

, Article Computational and Theoretical Chemistry ; Volume 1018 , 2013 , Pages 35-44 ; 2210271X (ISSN) Bayat, A ; Fattahi, A ; Sharif University of Technology

2013

Abstract

The free radical scavenging activity of a series of hydroxybenzohydroxamic acid derivatives have been studied in gas phase, water and benzene environments, using the density functional theory. Different mechanisms of reactions have been considered: single electron transfer (SET), hydrogen atom transfer (HAT). Rate constants were determined to know if the radical scavenging activity of these compounds proceeds via an H-atom or an electron-transfer mechanism. Calculations showed that the presence of the adjacent hydroxyl groups on phenyl ring increases the radical stability through intramolecular hydrogen bonds. The calculated bond dissociation enthalpy (BDE) values for hydroxyl groups on...

A quantum chemical study on the OH radical quenching by natural antioxidant fisetin

, Article Journal of Physical Organic Chemistry ; Volume 30, Issue 11 , 2017 ; 08943230 (ISSN) Bayat, A ; Fattahi, A ; Sharif University of Technology

2017

Abstract

In this work, the antioxidant ability of fisetin was explored toward hydroxyl (•OH) radical in aqueous and lipid solution using density functional level of theory. Different reaction mechanisms have been studied: hydrogen atom transfer, single electron transfer followed by proton transfer, and radical adduct formation, and sequential proton loss electron transfer. Rate constants for all possible reaction sites have been calculated using conventional transition state theory in conjunction with the Collins-Kimball theory. Branching ratios for the different channels of reaction are reported for the first time. Results show that the reactivity of fisetin toward hydroxyl (•OH) radical takes place...

Influence of remote intramolecular hydrogen bonding on the acidity of hydroxy-1,4-benzoquinonederivatives: A DFT study

, Article Journal of Physical Organic Chemistry ; Volume 32, Issue 4 , 2019 ; 08943230 (ISSN) Bayat, A ; Fattahi, A ; Sharif University of Technology

John Wiley and Sons Ltd 2019

Abstract

In this study, the effects of the remote intramolecular hydrogen bonding on the acidity of hydroxy-1,4-benzoquinone derivatives have been investigated ab initio by employing density functional theory (DFT) methods. The computational studies were performed for both gas and solution (H 2 O, DMSO, and MeCN solutions) phases. Our results indicated that remote hydrogen bonding could play an important role in increasing the acidity of hydroxy-1,4-benzoquinone. Noncovalent interaction reduced density gradient (NCI-RDG) methods were used to visualize the attractive and repulsive interactions in the studied acids and their conjugate bases. Natural bond orbital (NBO) analysis was performed to confirm...

An optimal hybrid nuclear norm regularization for matrix sensing with subspace prior information

, Article IEEE Access ; Volume 8 , 2020 , Pages 130937-130946 Bayat, S ; Daei, S ; Sharif University of Technology

Institute of Electrical and Electronics Engineers Inc 2020

Abstract

Matrix sensing refers to recovering a low-rank matrix from a few linear combinations of its entries. This problem naturally arises in many applications including recommendation systems, collaborative filtering, seismic data interpolation and wireless sensor networks. Recently, in these applications, it has been noted that exploiting additional subspace information might yield significant improvements in practical scenarios. This information is reflected by two subspaces forming angles with column and row spaces of the ground-truth matrix. Despite the importance of exploiting this information, there is limited theoretical guarantee for this feature. In this work, we aim to address this issue...

The free radical scavenging activity of lespedezacoumestan toward ˙OH radical: a quantum chemical and computational kinetics study

, Article Journal of Physical Organic Chemistry ; Volume 31, Issue 2 , February , 2018 ; 08943230 (ISSN) Bayat, A ; Fattahi, A ; Sharif University of Technology

John Wiley and Sons Ltd 2018

Abstract

The free radical activity of lespedezacoumestan was investigated toward hydroxyl (˙OH) radical in polar and nonpolar media using density functional theory. Four reaction mechanisms including radical adduct formation, hydrogen atom transfer, sequential single electron-proton transfer (SET-PT), and sequential proton loss electron transfer were considered. The rate constants and branching ratio for all possible sites of reaction were calculated and reported for the first time. According to the obtained results, lespedezacoumestan reacts faster with ˙OH radical in aqueous solution than in nonpolar media. Also, lespedezacoumestan is an excellent ˙OH radical scavenger regardless of the environment...

Transfer of d -level quantum states through spin chains by random swapping

, Article Physical Review A - Atomic, Molecular, and Optical Physics ; Volume 75, Issue 2 , 2007 ; 10502947 (ISSN) Bayat, A ; Karimipour, V ; Sharif University of Technology

2007

Abstract

We generalize an already proposed protocol for quantum state transfer to spin chains of arbitrary spin. An arbitrary unknown d -level state is transferred through a chain with rather good fidelity by the natural dynamics of the chain. We compare the performance of this protocol for various values of d. A by-product of our study is a much simpler method for picking up the state at the destination as compared with the one proposed previously. We also discuss entanglement distribution through such chains and show that the quality of entanglement transition increases with the number of levels d. © 2007 The American Physical Society

Separating radar signals from impulsive noise using atomic norm minimization

, Article IEEE Transactions on Circuits and Systems II: Express Briefs ; Volume 68, Issue 6 , 2021 , Pages 2212-2216 ; 15497747 (ISSN) Bayat, S ; Daei, S ; Sharif University of Technology

Institute of Electrical and Electronics Engineers Inc 2021

Abstract

We consider the problem of corrupted radar super-resolution, a generalization of compressed radar super-resolution in which one aims to recover the continuous-valued delay-Doppler pairs of moving objects from a collection of corrupted and noisy measurements. The received signal in this type consists of contributions from objects, outlier and noise. While this problem is ill-posed in general, tractable recovery is possible when both the number of objects and corrupted measurements are limited. In this brief, we propose an atomic norm optimization in order to find the delay-Doppler pairs and the outlier signal. The objective function of our optimization problem encourages both sparsity in the...

Thermal effects on quantum communication through spin chains

, Article Physical Review A - Atomic, Molecular, and Optical Physics ; Volume 71, Issue 4 , 2005 ; 10502947 (ISSN) Bayat, A ; Karimipour, V ; Sharif University of Technology

2005

Abstract

We study the effect of thermal fluctuations in a recently proposed protocol for transmission of unknown quantum states through quantum spin chains. We develop a low-temperature expansion for general spin chains. We then apply this formalism to study exactly thermal effects on short spin chains of four spins. We show that optimal times for extraction of output states are almost independent of the temperature, which lowers only the fidelity of the channel. Moreover we show that thermal effects are smaller in the antiferromagnetic chains than the ferromagnetic ones. © 2005 The American Physical Society

Advances in UAV-assisted localization: joint source and UAV parameter estimation

, Article IEEE Transactions on Vehicular Technology ; Volume 72, Issue 11 , 2023 , Pages 14268-14278 ; 00189545 (ISSN) Bayat, S ; Amiri, R ; Sharif University of Technology

Institute of Electrical and Electronics Engineers Inc 2023

Abstract

This paper presents efficient estimators to address the problem of source localization aided by unmanned aerial vehicles (UAVs) with unknown location parameters. Leveraging semidefinite relaxation technique and successive weighted least squares estimation, the source and UAV parameters are simultaneously estimated in both mixed line-of-sight/non-line-of-sight (NLOS) and NLOS scenarios. The proposed estimators are shown to approximately achieve the Cramer-Rao bound (CRB) under mild Gaussian noise conditions when the measurement noises are small compared to the associated ranges. Numerical simulations demonstrate that localization without prior UAV location information is still possible with a...

Application of Diazonium Salts for Grafting the Sol-gel Based Sorbents: A New Approach Towards Unbreakable SPME

, M.Sc. Thesis Sharif University of Technology Bayat, Parisa (Author) ; Bagheri, Habib (Supervisor)

Abstract

A novel application of diazonium salts for grafting the sol-gel based sorbents was sucessfully introduced. Preparation of unbrekable sorbents has been on highly demand and sough after by many researches for several years. However, there are a few achivements in this regard, but it still remains as a big challenge.Regarding to this issue, diazonium salts were sucessfully applied for functionalizing the different substrates, in which there is no limitation in selection of substrates. Different substrates, metallic and non metallic, such as copper, brass, stailess steel and PTFE were chosen to be functionalized by chemical or electrochemical reduction of 4-Amino phenyl acetic acid. Then,...

A Locality Aware P2P Overlay Architecture for Video Streaming

, M.Sc. Thesis Sharif University of Technology Bayat, Navid (Author) ; Akbari, Behzad (Supervisor)

Abstract

Internet video networks have already attracted millions of Internet users, and Internet video is one of the fast growing Internet services. The peer-to-peer (P2P) network is an efficient solution to supporting large scale video streaming on the Internet. P2P networks can deliver live multimedia content to millions of users with low cost at any time, and at anywhere they want. In this thesis, we investigate solutions to enhancing the performance of the unstructured mesh-based. Locality awareness or network proximity is one of the essential characteristics of P2P networks. In live P2P video streaming we face to some challenges like bandwidth heterogeneity of peers, and peer churn. In the P2P...

Voltammetric Determination of Tryptophan and 5-Hydroxytryptophan Using Graphite Electrode Modified with a Thin Film of Graphite/Diamond Nano-mixture And Determination of omeprazole Using Graphite Electrode

, M.Sc. Thesis Sharif University of Technology Bayat, Maryam (Author) ; Shahrokhian, Saeed (Supervisor)

Abstract

At the first part of this thesis, a pyrolitic graphite electrode (PGE) modified with graphite/nanodiamond film (GND) was applied as a sensitive electrochemical sensor for determination and study of electrochemical behavior of tryptophan (Trp) and 5-hydroxytryptophan (5-HTP) in aqueous solutions. The results showed that GND caused a remarkable increase in the peak currents so the GND/PGE electrode surface was more sensitive to the concentration of Trp and 5-HTP than the PGE surface. The determination of Trp and 5-HTP were investigated by stripping voltammetry. Experimental parameters such as scan rate, pH, accumulation conditions and amount of the modifier used on the PGE surface were...