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Low-Frequency model for hand-calculations in circuit design with TMDC-based transistors
, Article IEEE Transactions on Electron Devices ; Volume 66, Issue 11 , 2019 , Pages 5011-5018 ; 00189383 (ISSN) ; Safarian, A ; Pourfath, M ; Sharif University of Technology
Institute of Electrical and Electronics Engineers Inc
2019
Abstract
This article presents an applicable intuitive current-voltage model for long-channel transistors based on 2-D materials. This model carefully predicts the transistor behavior in the saturation and triode regions, which are important for analog and digital applications. Moreover, the effect of mobility degradation on the characteristics of the transistor is probed. As a case study, the developed model has been applied to a transistor with mono-layer MoS2 as the channel material. The excellent agreement with experimental data verifies the accuracy of the model. Finally, the introduced model has been utilized to design an amplifier, a differential pair, and a low-frequency common source mixer...
Low-frequency Model for Long-channel Monolayer Transistors
, Ph.D. Dissertation Sharif University of Technology ; Safarian, Amin Ghasem (Supervisor) ; Pourfath, Mahdi (Co-Supervisor)
Abstract
Transistors’ miniaturization and advent of short-channel effects causes searching for another devices with least adverse characteristics in short channels. Among all the considered devices, monolayer transistors attracted the attention. Although most of the papers in literature focused on the physical phenomenon of the device, circuit design of these transistors have been overlooked. Most of the papers related to monolayer transistors did not explain the design methodology of their circuits and they confined their work just to the report of the circuits constructed with 2D-based transistors. In order to take advantage of 2D materials in electronic circuits, simple modelling for...
Chemometrics-assisted isotope ratio fingerprinting based on gas chromatography/combustion/isotope ratio mass spectrometry for saffron authentication
, Article Journal of Chromatography A ; Volume 1657 , 2021 ; 00219673 (ISSN) ; Parastar, H ; Sharif University of Technology
Elsevier B.V
2021
Abstract
In the present contribution, the capability of isotopic ratio mass spectrometry (IRMS) for saffron authentication and detection of four common plant-derived adulterants (marigold flower, safflower, rubia, and saffron style) was investigated. For this purpose, 62 authentic saffron samples were analyzed by elemental analyzer-IRMS (EA-IRMS) and gas chromatography-combustion-IRMS (GC-C-IRMS). In this regard, EA-IRMS and GC-C-IRMS isotope fingerprints of carbon-13 and nitrogen-15 isotopes of saffron components were provided and then analyzed by chemometric methods. Principal component analysis (PCA) showed two different behaviors regarding two main regions. Then, a representative saffron sample...
Throughput-memory footprint trade-off in synthesis of streaming software on embedded multiprocessors
, Article Transactions on Embedded Computing Systems ; Volume 13, Issue 3 , December , 2013 ; 15399087 (ISSN) ; Foroozannejad, M. H ; Ghiasi, S ; Sharif University of Technology
2013
Abstract
We study the trade-off between throughput and memory footprint of embedded software that is synthesized from acyclic static dataflow (task graph) specifications targeting distributed memory multiprocessors. We identify iteration overlapping as a knob in the synthesis process by which one can trade application throughput for its memory requirement. Given an initial processor assignment and non-overlapped task schedule, we formally present underlying properties of the problem, such as constraints on a valid iteration overlapping, maximum possible throughput, and minimum memory footprint. Moreover, we develop an effective algorithm for generation of a rich set of design points that provide a...
Formless: scalable utilization of embedded manycores in streaming applications
, Article Proceedings of the ACM SIGPLAN Conference on Languages, Compilers, and Tools for Embedded Systems (LCTES) ; 2012 , Pages 71-78 ; 9781450312127 (ISBN) ; Foroozannejad, M. H ; Ghiasi, S ; Etzel, C ; Sharif University of Technology
2012
Abstract
Variants of dataflow specification models are widely used to synthesize streaming applications for distributed-memory parallel processors. We argue that current practice of specifying streaming applications using rigid dataflow models, implicitly prohibits a number of platform oriented optimizations and hence limits portability and scalability with respect to number of processors. We motivate Functionally-cOnsistent stRucturally-MalLEabe Streaming Specification, dubbed FORMLESS, which refers to raising the abstraction level beyond fixed-structure dataflow to address its portability and scalability limitations. To demonstrate the potential of the idea, we develop a design space exploration...
Inclusion of Pediococcus acidilactici as probiotic candidate in diets for beluga (Huso huso) modifies biochemical parameters and improves immune functions
, Article Fish Physiology and Biochemistry ; Volume 44, Issue 4 , 2018 , Pages 1099-1107 ; 09201742 (ISSN) ; Binaii, M ; Naghavi, A ; Khoshbavar Rostami, H ; Nori, H ; Amerizadeh, A ; Sharif University of Technology
Springer Netherlands
2018
Abstract
Administration of probiotic candidates in fish has generally been shown as a useful strategy to improve growth performance, survival, digestive enzyme activity, and gut microbiota. Unfortunately, the sero-immunological responses of different fish to different probiotic candidates are poorly understood. The present study assessed the effect of Pediococcus acidilactici as a probiotic on the biochemical and immunological parameters of beluga. Fish (248.32 ± 10.21 g) were fed a control diet (without P. acidilactici(and three different doses of P. acidilactici-supplemented diets (107, 108, and 109 CFUg−1 diets) for 8 weeks. On week 8, blood and serum were sampled. Dose-dependent increase of...
CNNdroid: GPU-accelerated execution of trained deep convolutional neural networks on android
, Article 24th ACM Multimedia Conference, MM 2016, 15 October 2016 through 19 October 2016 ; 2016 , Pages 1201-1205 ; 9781450336031 (ISBN) ; Golestani, H ; Hashemi, M ; Ghiasi, S ; Sharif University of Technology
Association for Computing Machinery, Inc
2016
Abstract
Many mobile applications running on smartphones and wear- able devices would potentially benefit from the accuracy and scalability of deep CNN-based machine learning algorithms. However, performance and energy consumption limitations make the execution of such computationally intensive algorithms on mobile devices prohibitive. We present a GPU- accelerated library, dubbed CNNdroid [1], for execution of trained deep CNNs on Android-based mobile devices. Empirical evaluations show that CNNdroid achieves up to 60X speedup and 130X energy saving on current mobile devices. The CNNdroid open source library is available for download at https://github.com/ENCP/CNNdroid
Conformational study of a strained tolanophane by dynamic 1H NMR spectroscopy and computational methods
, Article Monatshefte fur Chemie ; Volume 139, Issue 10 , 2008 , Pages 1185-1189 ; 00269247 (ISSN) ; Azimzadeh Arani, M ; Tafazzoli, M ; Ghiasi, M ; Sharif University of Technology
2008
Abstract
The existence of a short C-H⋯π (alkyl-alkyne) interaction in the structure of a strained and relatively rigid tolanophane is expected to hinder the rotation about the C-C sp3 single bond. Variable-temperature NMR experiments (performed in three solvents, CDCl3, THF-d8, and acetone-d6) and ab initio density functional calculations were carried out to investigate its dynamic nature. An energy barrier of 48.6 kJ/mol is determined at coalescence (210 K) with acetone-d6 which is in good agreement with calculation result (54 kJ/mol). © 2008 Springer-Verlag
An Integrated Land-Use and Transportation Model for the Evaluation of Urban Development Decisions
, M.Sc. Thesis Sharif University of Technology ; Poorzahedy, Hossain (Supervisor)
Abstract
Land-use and transportation are inter-related, such that land-use may be used to control transportation. This study aims to design a suitable combination of the residential and service land-use on one side, and the transportation system on the other side. The model presented in this study has two external and internal levels, and its objective is to minimize the cost of residence, receiving goods and services, and transportation. The performance of any combination of spatial allocation of population and employment, as well as transportation, is evaluated by the internal level of the model which determines the interaction between population, employment, and transportation. This is done by a...
Cramér’s Model for Random Primes
, M.Sc. Thesis Sharif University of Technology ; Alishahi, Kasra (Supervisor)
Abstract
With Cramer’s model we have a probability measure on the power set of N. This probability measure is concentrated on the set that its elements are that subsets of N which number of their elements up to a certain natural number is asymptotically equal with the number of primes up to the same number. Let Pc be a sample obtained from this probability measure and consider 8n 2 N, an counts the number of ways that ncan be represented as a multiplication of some elements of Pc, such that changing the arrangement of factors in a representation does not introduce a new one. In this thesis, we prove that limn!1 a1++an n almost surely exists and is positive
Study & Analysis of Delays Causes of Gas Projects in Tehran Gas Company & presenting Optimized Solutions by Applying Project Management Principles
, M.Sc. Thesis Sharif University of Technology ; Mostafavi, Mostafa (Supervisor)
Abstract
To deliver gas in time to different consumers like as industrial, commercial and domestic users is one of the most important parts in gas industry. So it is very important to utilize these projects in the specified time. There are huge harms for client, contractors and consumers when there is a delay in project utilization. To identify effective parameters on delays to remove them in future is an essential factor. In this research, all delay causes for TPGC (Tehran Province Gas Company) projects are analyzed and some solutions to remove these delays are presented. 10 hypotheses in relation of gas delivery have been assumed as delay causes. Then some questions have been discussed in relation...
Experimental investigation of the effect of using thermosyphon heat pipes and vacuum glass on the performance of solar still
, Article Energy ; Volume 75 , 2014 , pp. 501–507 ; ISSN: 03605442 ; Gholami Derami, H ; Ghiasi, M ; Shafii, M. B ; Shiee, Z ; Sharif University of Technology
2014
Abstract
A desalination system consumes energy for production of freshwater. Since the solar energy is a low-cost, environmentally clean, and available energy throughout the world, it could be the best source of energy for such systems. In this work, a modified desalination system is presented which uses advantages of thermosyphon heat pipes as a fast and high performance thermal conducting device, and at the same time, employs the advantages of evacuated tube collectors (ETCs) which are flexible and have high performance in adverse weather conditions. Results show considerable increase in the production rate of desalinated water and system efficiency with a maximum production rate of 1.02 kg/(m2 h)...
Dynamic stereochemistry of rutin (vitamin P) in solution: Theoretical approaches and experimental validation
, Article Carbohydrate Research ; Volume 345, Issue 12 , 2010 , Pages 1760-1766 ; 00086215 (ISSN) ; Taheri, S ; Tafazzoli, M ; Sharif University of Technology
2010
Abstract
The 3D structure of vitamin P, an important bioflavonoid, has been studied in solution by 2D NMR spectroscopy and QM calculations. Rutin, vitamin P, was extracted from Salvia macrosiphon and identified by 1H, 13C, 1H-1H COSY, HMQC, and HMBC spectroscopy. In parallel, density functional theory (DFT) using B3LYP functional and split-valance 6-311G basis set has been used to optimize the structures and conformers of rutin. Also experimental and theoretical methods have been used to correlate the dependencies of 1J, 2J, and 3J involving 1H and 13C on the C5″-C6″ (ω), C6″-O6″ (θ), and C1‴-O6″ () torsion angles in the glycosidic moiety. New Karplus equations are proposed to assist in the...
Chrysin/β-cyclodextrin supramolecular system: a quantum mechanical investigation
, Article Journal of the Iranian Chemical Society ; Volume 15, Issue 10 , 2018 , Pages 2401-2410 ; 1735207X (ISSN) ; Gerayeli, N ; Tafazzoli, M ; Sharif University of Technology
2018
Abstract
Chrysin is a bioflavonoid which possesses a wide range of important biological activities. In present study, we used a quantum mechanical approach to shed light on the antioxidant ability and antioxidant mechanism of chrysin to scavenge hydroxyl radical (˙OH) in solution phase. The analysis of the theoretical bond dissociation enthalpy (BDE) values and spin density of the radicals to determine the delocalization possibilities at B3LYP/6-311++G** level clearly shows the importance of the A-ring and the 7-OH group in antioxidant reactivity. In the next step, the inclusion of chrysin with β-CD has been investigated extensively using theoretical methods. Density functional theory (M05-2X)...
The Control of an exoskeleton and the reduction of interaction force using human intent detection by EMG signals and torque estimation
, Article Proceedings of the 6th RSI International Conference on Robotics and Mechatronics, IcRoM 2018, 23 October 2018 through 25 October 2018 ; 2019 , Pages 536-541 ; 9781728101279 (ISBN) ; Vossoughi, G. R ; Sharif University of Technology
Institute of Electrical and Electronics Engineers Inc
2019
Abstract
Disability and motor disorders are some of the problems that people may face due to some factors such as accident, spinal cord injuries, brain damage, and the presence of a problem in neurological commands due to stroke. One of the proposed methods for solving the problems of these people is the use of exoskeletons to generate movement. The main goal of this paper is the control of Sharif Exoskeleton Robot and the reduction of interaction force between user and robot by using human intent detection. This goal is done by estimating the knee torque of one degree of freedom in a swing phase using Hill model based on the EMG data from the thigh muscles. Accordingly, the calibration algorithm is...
Role of axial ligand on the electronic structures of active intermediates in cytochrome P-450, peroxidase and catalase
, Article Journal of Molecular Structure: THEOCHEM ; Volume 820, Issue 1-3 , 2007 , Pages 18-25 ; 01661280 (ISSN) ; Tafazzoli, M ; Safari, N ; Sharif University of Technology
2007
Abstract
DFT method (B3LYP) with 6-31G* basis set was utilized in the computation of a fully optimized structure, net atomic charges and spin densities of the intermediate of cytochrome P-450-oxoiron(IV) porphyrin cation radical, compound I - in the presence of axial ligand such as thiolate (SMe-) imidazole (IM), phenoxide (OPh-), methoxide (OMe-) and chloride (Cl-). The results show doublet states in compound I are about 2-4 kcal/mol more stable than quartet states for all aforementioned ligands, and the doublet state is the ground state in all cases. However, electron donor ability of the ligands are in the order of SMe- > IM > OMe- > OPh- > Cl-. Also the active oxidant intermediate of cytochrome...
Knee Joint Torque Estimation using EMG Signals for Sharif Exoskeleton Control Applications
, M.Sc. Thesis Sharif University of Technology ; Vossoughi, Gholamreza (Supervisor)
Abstract
The human body has more than 600 muscles that cause movement. Disability and motor disorders are some of the problems that people may face due to some factors such as accident, spinal cord injuries, disorders and brain damage, and the presence of a problem in neurological commands due to stroke. One of the proposed methods for solving the problems of people with motor disorder is the use of exoskeletons to generate stimulus. Exoskeletones are electromechanical devices designed to assist human movement, and patients are used to correct their movements using specific motor patterns. Exoskeletones can also be used as an auxiliary device for carrying heavy loads. Many studies have been conducted...
Development of Chemometric Methods Combined with Isotope Ratio Mass Spectrometry (IRMS) for Isotope Pattern Recognition and Adulteration Detection in Foods
, M.Sc. Thesis Sharif University of Technology ; Parastar Shahri, Hadi (Supervisor)
Abstract
The purpose of this study was to investigate the capability of Isotopic Ratio Mass Spectrometry (IRMS) in the detection of four common natural plant frauds in saffron, namely Marigold flower, Safflower, Rubia and Saffron Style. For this purpose, first natural saffron isotopes were analyzed and used to investigate fingerprints of carbon-13 and nitrogen-15 isotopes by Elemental Analyzer Isotopic Ratio Mass Spectrometry (EA-IRMS) and carbon-13 isotopic ratio of saffron components by Gas Chromatography Isotopic Ratio Mass Spectrometry (GC-C-IRMS). Then, according to the isotopic behavior of the original saffron, they were sampled to form a mixture of saffron that is representative of the...
Cross-sectional area of human trunk paraspinal muscles before and after posterior lumbar surgery using magnetic resonance imaging
, Article European Spine Journal ; Volume 25, Issue 3 , 2016 , Pages 774-782 ; 09406719 (ISSN) ; Arjmand, N ; Shirazi Adl, A ; Farahmand, F ; Hashemi, H ; Bagheri, S ; Valizadeh, M ; Sharif University of Technology
Springer Verlag
2016
Abstract
Atrogenic injuries to paraspinal muscles during the posterior lumbar surgery (PLS) cause a reduction in their cross-sectional areas (CSAs) and contractile densities over time post-surgery. This study aims to quantify such alterations. Method: Pre- and postoperative CSAs (~6 months interval) of all paraspinal muscles were measured in six patients undergoing PLS using a 3-T magnetic resonance (MR) scanner to quantify the alterations in geometrical and tissue effective contractile (non-fatty) CSAs of these muscles at all lumbar levels. To examine the presence of any confounding effects on recorded changes within ~7-month period, measurements were also carried out on ten healthy volunteers....
A new model reference adaptive control structure for uncertain switched systems with unmodeled input dynamics
, Article Transactions of the Institute of Measurement and Control ; Volume 37, Issue 10 , 2015 , Pages 1171-1180 ; 01423312 (ISSN) ; Rikhtehgar Ghiasi, A ; Karimi Fazli, A ; Sharif University of Technology
SAGE Publications Ltd
2015
Abstract
In this paper, a new model reference adaptive controller (MRAC) for uncertain switched linear systems is developed. A class of uncertain switched linear systems with parametric mismatched and input matched uncertainties, control input effectiveness and unmodeled dynamics is studied in this paper. The difference in input matrix for different switching modes which means the input channel degradation is investigated through this paper. By using common Lyapunov function method and developing new linear matrix inequality based sufficient conditions, uniform ultimate boundedness of the reference tracking error is guaranteed by switched MRAC and by using a novel nonlinear controller term, the size...