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A comparative study of energy/power consumption in parallel decimal multipliers
, Article Microelectronics Journal ; Vol. 45, Issue 6 , June , 2014 , pp. 775-780 ; Ejlali, A ; Gorgin, S ; Sharif University of Technology
2014
Abstract
Decimal multiplication is a frequent operation with inherent complexity in implementation. Commercial and financial applications require working with decimal numbers while it has been shown that if we convert decimal number to binary ones, this will negatively influence the preciseness required for these applications. Existing research works on parallel decimal multipliers have mainly focused on latency and area as two major factors to be improved. However, energy/power consumption is another prominent issue in today's digital systems. While the energy consumption of parallel decimal multipliers has not been addressed in previous works, in this paper we present a comparative study of...
Improving the energy/power consumption of parallel decimal multipliers
, Article Indian Journal of Science and Technology ; Vol. 7, issue. 3 , 2014 , p. 276-281 ; Ejlali, A ; Sharif University of Technology
2014
Abstract
Decimal arithmetic has gained intensive attention in the last decade. Most commercial, financial, scientific, and internet-based applications need their data to be precise, while binary number system loses preciseness in some cases. The latency and area are two major factors in existing research works on decimal multiplication. However, energy/power consumption is another important factor in today's digital systems. Hence, in this paper we proposed a new low power decimal adder based on prediction technique for decreasing the energy/power consumption of parallel decimal multiplication and show its impacts on one of the well-known parallel decimal multipliers architecture. Our observations...
Effects of geometry aspects on the simulation of superplasticity in MMC composites
, Article 25th Congress of the International Council of the Aeronautical Sciences 2006, Hamburg, 3 September 2006 through 8 September 2006 ; Volume 3 , 2006 , Pages 1915-1923 ; Barakati, A ; Malekpour, A ; Sharif University of Technology
Curran Associates Inc
2006
Abstract
In aerospace applications, the weight of structures is considered as a major performance parameter. One of the most effective ways for weight reduction is superplastic forming. By this technique, not only the weight, but also the stress concentration, the cost, and the time of manufacturing are noticeably reduced. Additionally, the components with complicated shapes could be formed in a single manufacturing step. Due to the wide demand for whiskers reinforced metal matrix composites (MMC's) in aerospace applications, many research works have been designed to extend the boarders of superplastic forming of metals to the area of MMC manufacturing. In the present study, the FEM modeling of...
Analysis of bioactive constituents of saffron using ultrasonic assisted emulsification microextraction combined with high-performance liquid chromatography with diode array detector: A chemometric study
, Article RSC Advances ; Volume 5, Issue 33 , 2015 , Pages 26246-26254 ; 20462069 (ISSN) ; Parastar, H ; Malekpour, A ; Sharif University of Technology
Royal Society of Chemistry
2015
Abstract
In recent years, there has been an increasing interest in the analysis of the major active components of saffron owing to their significant role in various industries, such as food, medicine and perfume. In other words, analysis of the major active components of saffron can give complete information about its chemical composition, which can be used as a reliable index for the quality control of different saffron samples (i.e., natural and commercial). The aim of the present work was to develop a simple, low cost, efficient and comprehensive strategy for the extraction and analysis of the bioactive components of saffron. In this regard, ultrasonic-assisted solvent extraction (UASE) combined...
Smart Water Injection to the Oil Fields for Enhancing the Recovery Factor
, M.Sc. Thesis Sharif University of Technology ; Farhadi, Alireza (Supervisor)
Abstract
The objective of this MSc. thesis is to study the impact of the reactive method and the enhanced reactive method on enhancing the exploitation efficiency of Iran's offshore oil reservoir. This is achieved by enhancing production and the recovery factor of the reactive methods with respect to the currently used proactive method. Unlike the currently used proactive method that implements a fixed rate injection strategy, in this MSc. thesis water is injected to reservoir with multi-rate for the pressure stabilization of the reservoir. In order to scale up this strategy, the ensemble Kalman filter is used to frequently update the reservoir mathematical model using the available measurements from...
Electrochemical performance and elevated temperature properties of the TiO2-Coated Li[Ni0.8Co0.1Mn0.1]O2 cathode material for high-safety li-ion batteries
, Article ACS Applied Energy Materials ; Volume 4, Issue 5 , 2021 , Pages 5304-5315 ; 25740962 (ISSN) ; Azar, M. K ; Esmaeili, M ; Malekpour, N ; Hosseini Hosseinabad, S. M ; Moakhar, R. S ; Dolati, A ; Ramakrishna, S ; Sharif University of Technology
American Chemical Society
2021
Abstract
Nowadays, the LiNi0.8Co0.1Mn0.1O2 (NCM811) cathode material has attracted great research interest due to its high energy density and less usage of costly raw materials. However, the high nickel content of NCM811 brings about an extremely unstable interface between the electrode and electrolyte and therefore inferior cyclic stability. Herein, we have proposed a straightforward method to deliver 1, 2, and 4 wt % of TiO2 nanoparticles (NPs) on the surface of the NCM811 cathode material and to improve its properties at room and high temperatures. Based on scanning electron microscopy and transmission electron microscopy observations, the coating thickness varies from 10 to 35 nm and the 2 wt %...
Low-power Design of Decimal Multipliers
, M.Sc. Thesis Sharif University of Technology ; Ejlali, Ali Reza (Supervisor)
Abstract
Decimal multiplication is a frequent operation with inherent complexity in implementation. Commercial and financial applications require their data to be precise while binary number system cannot ensure precision. Existing research works on parallel decimal multipliers have mainly focused on latency and area as two major factors to be improved. However, energy/power consumption is another prominent issue in today’s digital systems. Hence, in this thesis we present a comparative study of parallel decimal multipliers, considering energy/power consumption (leakage and dynamic power consumption), latency and area. Furthermore, we present two novel techniques to reduce energy/power consumption of...
Modeling the probability distribution of the bacterial burst size via a game-theoretic approach
, Article Journal of Bioinformatics and Computational Biology ; Volume 16, Issue 4 , 2018 ; 02197200 (ISSN) ; Pakzad, P ; Foroughmand Araabi, M. H ; Goliaei, S ; Tusserkani, R ; Goliaei, B ; Sadeghi, M ; Sharif University of Technology
World Scientific Publishing Co. Pte Ltd
2018
Abstract
Based on previous studies, empirical distribution of the bacterial burst size varies even in a population of isogenic bacteria. Since bacteriophage progenies increase linearly with time, it is the lysis time variation that results in the bacterial burst size variations. Here, the burst size variation is computationally modeled by considering the lysis time decisions as a game. Each player in the game is a bacteriophage that has initially infected and lysed its host bacterium. Also, the payoff of each burst size strategy is the average number of bacteria that are solely infected by the bacteriophage progenies after lysis. For calculating the payoffs, a new version of ball and bin model with...
A Novel Service Composition Model for Sustainable Cloud Supply Chain Using Stochastic Programming Approach
, M.Sc. Thesis Sharif University of Technology ; Fatahi Valilai, Omid (Supervisor)
Abstract
Along with globalization of competition and economy, and development of Internet and Ethernet infrastructures, IoT, artificial intelligence, etc., to modify the impact of changes and volatility, active organizations and product chains have faced with an advanced service-oriented manufacturing model based on complicated networks of operation and logistics service providers. On the other hand, appearing of individualized and customized orders have leaded to more complicated manufacturing procedure and manufacturing industries have been more restricted to satisfy varied demands. In the context of physical products and cyberspace convergence, the novel generation of advanced manufacturing...
Mathematical study of probe arrangement and nanoparticle injection effects on heat transfer during cryosurgery
, Article Computers in Biology and Medicine ; Volume 66 , Nov , 2015 , Pages 113-119 ; 00104825 (ISSN) ; Ramazani S. A. A ; Nazemidashtarjandi, S ; Sharif University of Technology
Elsevier Ltd
2015
Abstract
Blood vessels, especially large vessels have a greater thermal effect on freezing tissue during cryosurgery. Vascular networks act as heat sources in tissue, and cause failure in cryosurgery and reappearance of cancer. The aim of this study is to numerically simulate the effect of probe location and multiprobe on heat transfer distribution. Furthermore, the effect of nanoparticles injection is studied. It is shown that the small probes location near large blood vessels could help to reduce the necessary time for tissue freezing. Nanoparticles injection shows that the thermal effect of blood vessel in tissue is improved. Using Au, Ag and diamond nanoparticles have the most growth of ice ball...
Mechanical, rheological and oxygen barrier properties of ethylene vinyl acetate/diamond nanocomposites for packaging applications
, Article Diamond and Related Materials ; Volume 99 , 2019 ; 09259635 (ISSN) ; Ramazani S. A., A ; Haddadi, S. A ; Kheradmand, A ; Sharif University of Technology
Elsevier Ltd
2019
Abstract
In this work, the effects of the surface-modified nanodiamond particles (NDs) on the barrier, rheological, mechanical and thermal properties of ethylene vinyl acetate (EVA) composites for the packaging applications were investigated. Fourier transform infrared spectroscopy, as well as thermal gravimetric analysis were employed to study the grafting of vinyltriethoxy silane (VTS) on the surface of NDs. Afterwards, EVA samples containing 0, 0.1, 0.5, 1, 1.5 and 2 wt% of surface-modified NDs were prepared by a two-stage process including the solution and injection processes. In order to evaluate the physicochemical, rheological, mechanical and thermal properties of the EVA/NDs samples, field...
Effect of bonding parameters on microstructure development during TGTLP bonding of Al7075 alloy
, Article Philosophical Magazine ; Vol. 94, issue. 11 , Mar , 2014 , pp. 1166-1176 ; ISSN: 14786435 ; Ekrami, A ; Farahany, S ; Jahangiri, A ; Sharif University of Technology
2014
Abstract
The effect of temperature, pressure and bonding time on microstructure of temperature gradient transient liquid phase (TGTLP) diffusion bonded Al7075 alloy using liquid gallium interlayer was investigated. The selected bonding method relies on using the minimum amount of liquid gallium on faying surfaces, using a very fast heating rate to reach the joining temperature and imposing a temperature gradient across the bond region. The microstructure of the diffusion bonded joints was evaluated by light optical microscopy, scanning electron microscopy and energy dispersive spectroscopy (EDS). Results show that by increasing the temperature, pressure and time of joining, a more uniform...
Kalman filter based packet loss replacement in presence of additive noise
, Article 2012 25th IEEE Canadian Conference on Electrical and Computer Engineering: Vision for a Greener Future, CCECE 2012 ; 2012 ; 9781467314336 (ISBN) ; Ghorshi, S ; Tahaei, A
2012
Abstract
A major problem in real-time packet-based communication systems, is misrouted or delayed packets which results in degraded perceived voice quality. If packets are not available on time, the packets are considered as lost. The easiest solution in a network terminal receiver is to replace silence for the duration of lost speech segments. In a high quality communication system, to avoid degradation in speech quality due to packet loss, a suitable method or algorithm is needed to replace the missing segments of speech. In this paper, we introduce an adaptive filter for replacement of lost speech segment. In this method Kalman filter as a state-space based method will be used to predict the...
Effect of reactive diluent on gas separation behavior of photocurable acrylated polyurethane composite membranes
, Article Journal of Applied Polymer Science ; Volume 137, Issue 3 , 15 January , 2020 ; Shojaei, A ; Mousavi, S. A ; Ahmadi, S. A ; Sharif University of Technology
John Wiley and Sons Inc
2020
Abstract
In this study, the effects of the type and content of reactive diluents on the permeation/separation of carbon dioxide/nitrogen (CO2/N2) through acrylate-terminated polyurethane (APU)-acrylate/acrylic diluent (APUA) composite membranes was investigated. A series of APUs based on poly(ethylene glycol) (PEG)-1000 g mol−1, toluene diisocyanate, and 2-hydroxyethyl methacrylate was synthesized and then diluted with several reactive diluents. The results obtained from differential scanning calorimetry (DSC) and Fourier transform infrared analyses showed that the microphase interference of hard and soft segments increased with increasing reactive diluent content. Furthermore, with increasing alkene...
Study of thermal behavior of α-PbO2, using TG and DSC
, Article Journal of Thermal Analysis and Calorimetry ; Volume 92, Issue 3 , 2008 , Pages 917-920 ; 13886150 (ISSN) ; Alamolhoda, A. A ; Hashemian, S. J ; Sharif University of Technology
2008
Abstract
Using two techniques of thermogravimetry and differential scanning calorimetry under O2 gas atmosphere from 25 to 600°C, the thermal behavior of laboratory-produced compound lead(IV) oxide α-PbO2 was investigated. The identity of products at different stages were confirmed by XRD technique. Both techniques produced similar results supporting the same decomposition stages for the compound. Three distinct energy changes were observed, namely, two endothermic and one exothermic in DSC. The amount of ΔH for each peak is also reported. © 2008 Springer Science+Business Media, LLC
Thermal behavior of alkaline lead acetate, a study of thermogravimetry and differential scanning calorimetry
, Article Scientia Iranica ; Volume 15, Issue 4 , 2008 , Pages 435-439 ; 10263098 (ISSN) ; Alamolhoda, A. A ; Hashemian, S. J ; Sharif University of Technology
Sharif University of Technology
2008
Abstract
The compound, alkaline lead acetate, Pb(CH3COO)2·PbO·H2O (ALA), was purchased from the Fluka Company. The X-ray diffraction film and SEM electron microgaph of this compound were obtained and reported in this paper for the first time. The thermal behavior of alkaline lead acetate (ALA) was studied using thermogravimetery (TGA) and Differential Scanning Calorimetery (DSC) techniques under an O2 gas atmosphere from 25 to 600°C. Four distinct energy changes associated with weight changes were observed, all of them being exothermic in the DSC results. The amount of ΔH for each peak is reported. © Sharif University of Technology
An investigation into the structure and thermal properties of lead hydroxide
, Article Scientia Iranica ; Volume 14, Issue 2 , 2007 , Pages 169-173 ; 10263098 (ISSN) ; Alamolhoda, A. A ; Hashemian, S. J ; Sharif University of Technology
Sharif University of Technology
2007
Abstract
The compound, lead hydroxide Pb6O4(OH)4, was prepared by a method used for the first time in the authors laboratory. The compound was identified by XRD and it's purity was determined by analytical methods (100%). The thermal characteristics of this compound were investigated by using a thermogravimetry (TGA). This compound was found to be stable at room temperature and at 160°C will decompose completely to produce lead (II) oxide. © Sharif University of Technology, April 2007
Mechanical and piezoelectric characterizations of electrospun PVDF-nanosilica fibrous scaffolds for biomedical applications
, Article 2017 INN International Conference/Workshop on Nanotechnology and Nanomedicine, NTNM 2017, 2 May 2017 through 3 May 2017 ; Volume 5, Issue 7 , 2018 , Pages 15710-15716 ; 22147853 (ISSN) ; Ghaderi, S ; Amini, M ; Ramazani, S. A. A ; Sharif University of Technology
Elsevier Ltd
2018
Abstract
The effects of hydrophilic and hydrophobic nanosilica (SiO2) on the morphology, mean diameter distribution of fibers, mechanical and piezoelectric properties of poly (vinylidene fluoride) (PVDF) nanofibers were studies. We prepared Nanofibers by the electrospinning of PVDF solutions containing 1.5 wt.% both hydrophilic and hydrophobic nano-SiO2 loadings. Morphology and diameter distribution of the electrospun nanofibers were studied using field emission scanning electron microscopy (FE-SEM) analysis. Tensile test was used to study the effect of both types of nanosilica on the tensile strength, young's modulus and strain at break. Piezoelectric characterization of the electrospun fibers were...
Determining of the optimized dimensions of the Marinelli beaker containing source with inhomogeneous emission rate by using genetic algorithm coupled with MCNP and determining distribution type by neural networks
, Article Applied Radiation and Isotopes ; Volume 157 , 2020 ; Hosseini, S. A ; Feghhi, S. A ; Samadfam, M ; Sharif University of Technology
Elsevier Ltd
2020
Abstract
In order to determine the activity of C137s in soil resulting from nuclear accidents or fallouts, the best choice is to use HPGe detectors due to their best energy resolutions. In this regard, in order to enhance the detection efficiency, the Marinelli beakers have been used to increase the radiation interaction with the sensitive volume of the detector. In previous works, to optimize the dimension of Marinelli beakers, the assumption was that the emission rate of the source is homogeneous in beaker volume. In the present study, to investigate the effect of the inhomogeneous emission rate of the source on the optimum dimensions of the beaker, in a simple case, the beaker was divided into two...
Fabrication and characterization of a polysulfone-graphene oxide nanocomposite membrane for arsenate rejection from water
, Article Journal of Environmental Health Science and Engineering ; Volume 13, Issue 1 , 2015 ; 2052336X (ISSN) ; Nasseri, S ; Mahvi, A. H ; Nabizadeh, R ; Mousavi, S. A ; Rashidi, A ; Jafari, A ; Nazmara, S ; Sharif University of Technology
BioMed Central Ltd
2015
Abstract
Background: Nowadays, study and application of modified membranes for water treatment have been considered significantly. The aim of this study was to prepare and characterize a polysulfone (PSF)/graphene oxide (GO) nanocomposite membrane and to evaluate for arsenate rejection from water. Materials and methods: The nanocomposite PSF/GO membrane was fabricated using wet phase inversion method. The effect of GO on the synthesized membrane morphology and hydrophilicity was studied by using FE-SEM, AFM, contact angle, zeta potential, porosity and pore size tests. The membrane performance was also evaluated in terms of pure water flux and arsenate rejection. Results: ATR-FTIR confirmed the...