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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...
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...
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
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...
Implementation-aware model analysis: The case of buffer-throughput tradeoff in streaming applications
, Article Proceedings of the ACM SIGPLAN Conference on Languages, Compilers, and Tools for Embedded Systems (LCTES), 18 June 2015 through 19 June 2015 ; Volume 2015-June , 2015 , Pages 108-117 ; 9781450332576 (ISBN) ; Hashemi, M ; Khibin, V ; Ghiasi, S ; Sharif University of Technology
Association for Computing Machinery
2015
Abstract
Models of computation abstract away a number of implementation details in favor of well-defined semantics. While this has unquestionable benefits, we argue that analysis of models solely based on operational semantics (implementation oblivious analysis) is unfit to drive implementation design space exploration. Specifically, we study the tradeoff between buffer size and streaming throughput in applications modeled as synchronous data flow (SDF) graphs. We demonstrate the inherent inaccuracy of implementation-oblivious approach, which only considers SDF operational semantic. We propose a rigorous transformation, which equips the state of the art buffer-throughput tradeoff analysis technique...
Implementation-aware model analysis: The case of buffer-throughput tradeoff in streaming applications
, Article ACM SIGPLAN Notices ; Volume 50, Issue 5 , May , 2015 , Pages 103-112 ; 15232867 (ISSN) ; Hashemi, M ; Khibin, V ; Ghiasi, S ; Sharif University of Technology
Association for Computing Machinery
2015
Abstract
Models of computation abstract away a number of implementation details in favor of well-defined semantics. While this has unquestionable benefits, we argue that analysis of models solely based on operational semantics (implementationoblivious analysis) is unfit to drive implementation design space exploration. Specifically, we study the tradeoff between buffer size and streaming throughput in applications modeled as synchronous data flow (SDF) graphs. We demonstrate the inherent inaccuracy of implementationoblivious approach, which only considers SDF operational semantic. We propose a rigorous transformation, which equips the state of the art buffer-throughput tradeoff analysis technique...
Increasing the antioxidant activity of green tea polyphenols in the presence of iron for the reduction of graphene oxide
, Article Carbon ; Volume 50, Issue 8 , 2012 , Pages 3015-3025 ; 00086223 (ISSN) ; Kalaee, M ; Alavi, Z. S ; Ghiasi, S. M. A ; Esfandiar, A ; Sharif University of Technology
2012
Abstract
An easy method for green and low-temperature (40 °C) reduction of graphene oxide (GO) by increasing the antioxidant activity of green tea polyphenols (GTPs) in the presence of iron was developed. The reduction level (obtained by X-ray photoelectron spectroscopy) and electrical conductivity (obtained by current-voltage measurement) of the GO sheets reduced by GTPs in the presence of iron were comparable to those of hydrazine-reduced GO and much better than those of the GO reduced by only GTPs (in the absence of iron) at reduction temperatures of 40-80 °C. Raman spectroscopy indicated that application of GTPs in the presence of iron, in contrast to hydrazine, resulted in better recovering of...
Effect of two steps annealing on the microstructure and dynamic strain aging behavior of Al-6Mg alloy
, Article Materials Science and Engineering A ; Volume 798 , 2020 ; Khani Moghanaki, S ; Kazeminezhad, M ; Goodarzi, M ; Ghiasi Afjeh, S. M. B ; Sharif University of Technology
Elsevier Ltd
2020
Abstract
The microstructure of cold rolled Al–6Mg alloy is investigated after two steps annealing at different coupled temperatures of 250–320 °C and 320–400 °C for various times. Dynamic strain aging behavior in terms of serrated flow and strain rate sensitivity is investigated. The effect of three microstructural features, cell structure, recovered and recrystallized microstructures, on the strain rate sensitivity is elucidated. Two steps annealing process is utilized to capture the effect of recovery and precipitation phenomena on recrystallization and dynamic strain aging behaviors. The results show that the negative strain rate sensitivity of cold rolled specimen increases to positive values in...
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...
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
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...
Time-scalable mapping for circuit-switched GALS chip multiprocessor platforms
, Article IEEE Transactions on Computer-Aided Design of Integrated Circuits and Systems ; Vol. 33, issue. 5 , May , 2014 , p. 752-762 ; Hashemi, M ; Mahini, A ; Baas, B. M ; Ghiasi, S ; Sharif University of Technology
2014
Abstract
We study the problem of mapping concurrent tasks of an application to cores of a chip multiprocessor that utilize circuit-switched interconnect and global asynchronous local synchronous (GALS) clocking domains. We develop a configurable algorithm that naturally handles a number of practical requirements, such as architectural features of the target platform, core failures, and hardware accelerators, and in addition, is scalable to a large number of tasks and cores. Experiments with several real life applications show that our algorithm outperforms manual mapping, integer linear programming-based mapping after ten days of solver run time, and a recent packet-switched network on chip-based...
A novel stability and kinematics-driven trunk biomechanical model to estimate muscle and spinal forces
, Article Medical Engineering and Physics ; Vol. 36, issue. 10 , 2014 , p. 1296-1304 ; Arjmand, N ; Shirazi-Adl, A ; Farahmand, F ; Ghiasi, M. S ; Sharif University of Technology
2014
Abstract
An anatomically detailed eighteen-rotational-degrees-of-freedom model of the human spine using optimization constrained to equilibrium and stability requirements is developed and used to simulate several symmetric tasks in upright and flexed standing postures. Predictions of this stability and kinematics-driven (S. +. KD) model for trunk muscle forces and spine compressive/shear loads are compared to those of our existing kinematics-driven (KD) model where both translational and rotational degrees-of-freedom are included but redundancy is resolved using equilibrium conditions alone. Unlike the KD model, the S. +. KD model predicted abdominal co-contractions that, in agreement with...
Graphene oxide strongly inhibits amyloid beta fibrillation
, Article Nanoscale ; Volume 4, Issue 23 , 2012 , Pages 7322-7325 ; 20403364 (ISSN) ; Akhavan, O ; Ghavami, M ; Rezaee, F ; Ghiasi, S. M. A ; Sharif University of Technology
2012
Abstract
Since amyloid beta fibrillation (AβF) plays an important role in the development of neurodegenerative diseases, we investigated the effect of graphene oxide (GO) and their protein-coated surfaces on the kinetics of Aβ fibrillation in the aqueous solution. We showed that GO and their protein-covered surfaces delay the AβF process via adsorption of amyloid monomers. Also, the large available surface of GO sheets can delay the AβF process by adsorption of amyloid monomers. The inhibitory effect of the GO sheet was increased when we increase the concentration from 10% (in vitro; stimulated media) to 100% (in vivo; stimulated media). Conclusion: our results revealed that GO and their surface...
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...
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...
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...
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...