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    Intravenous laser wavelength irradiation effect on interleukins: Il-1α, il-1β, IL6 in diabetic rats

    , Article Laser Therapy ; Volume 28, Issue 4 , 2019 , Pages 267-273 ; 08985901 (ISSN) Amjadi, A ; Mirmiranpor, H ; Khandani, S ; Sobhani, S. O ; Shafaee, Y ; Sharif University of Technology
    Japan Medical Laser Laboratory  2019
    Abstract
    Background and aims: The main purpose of this investigation in Low-Level Laser Therapy (LLLT) on diabetic rats is laser wavelength effect on interleukins: IL-1α, IL-1β, IL6. Materials (Subjects) and Methods: At first, diabetes was induced in Wistar rats by streptozotocin (STZ) injection. Then, by intravenous laser therapy, the rats were irradiated by four continuous wave lasers: IR (λ = 808 nm), Red (λ = 638 nm), Green (λ = 532 nm) and Blue (λ = 450 nm) to compare the related laser wavelength effect on different interleukins. The inflammatory parameters were measured 2,6 and 24 hours after laser therapy from blood samples and plotted for different laser wavelengths. Results: The results show... 

    Sustainable Analysis of Unions Uses Axiomatic Design Theory with Focus on European Union

    , M.Sc. Thesis Sharif University of Technology Torbati, Mostafa (Author) ; Malaek, S. M (Supervisor)
    Abstract
    In this project, we examine the stability or sustainability issue in unions, in other words we want to know whether integration in European Union is stable? Countries have positive attitude toward unions and being member in unions is at special priorities. The main reason for countires is improve economy and national Security.
    The main question in this research is modeling European Union with Axiomatic Design Theory and analysis of sustainability based on this theory. This study has attempted to push Axiomatic Design Theroy in the new field of Systems Engineering and also it gives a new and differnet approach to stability.
     

    Reliable and energy efficient MLC STT-RAM buffer for CNN accelerators

    , Article Computers and Electrical Engineering ; Volume 86 , 2020 Jasemi, M ; Hessabi, S ; Bagherzadeh, N ; Sharif University of Technology
    Elsevier Ltd  2020
    Abstract
    We propose a lightweight scheme where the formation of a data block is changed in such a way that it can tolerate soft errors significantly better than the baseline. The key insight behind our work is that CNN weights are normalized between -1 and 1 after each convolutional layer, and this leaves one bit unused in half-precision floating-point representation. By taking advantage of the unused bit, we create a backup for the most significant bit to protect it against the soft errors. Also, considering the fact that in MLC STT-RAMs the cost of memory operations (read and write), and reliability of a cell are content-dependent (some patterns take larger current and longer time, while they are... 

    Design and Fabrication of an Optimized Wake Equalizing Duct in Order to Improve Propulsion System Operation

    , M.Sc. Thesis Sharif University of Technology Ali Mirzazadeh, Siamak (Author) ; Seif, Mohammad S (Supervisor) ; Rad, Manouchehr ($item.subfieldsMap.e)
    Abstract
    Special geometrical sections, known as “duct”, which can be installed on merchant vessels stern in order to improve propulsion system and propeller performance, today have evolved considerably. The force which produces by the propeller depends on efficiency of propulsion system. In the way of improving the efficiency of propulsion systems, by using these special geometrical sections, to much research have been done from the mid-twentieth century. The Wake Equalizing Ducts (WEDs) in addition to conduct the more uniform fluid flow to the propeller disk (which causes to improve the propeller operation), affect on flow separation in ship stern zone and will decrease the separated flow zone.... 

    Constrained single period problem under demand uncertainty

    , Article Scientia Iranica ; Volume 18, Issue 6 , December , 2011 , Pages 1553-1563 ; 10263098 (ISSN) Taleizadeh, A. A ; Shavandi, H ; Haji, R ; Sharif University of Technology
    2011
    Abstract
    In this paper, we develop the multi-product, multi-constraint, Single Period Problem (SPP) with uncertain demands, considering an incremental discount situation. Three new models are presented for multi-product, multi-constraint SPP in fuzzy, stochastic and rough environments. We consider constraints, such as service rate, restriction on order quantity and restrictions on warehouse space and budget. We also consider that the order quantity is a multiplier of predefined batch size. Furthermore, three kinds of solution algorithm, (1) harmony search, (2) hybrid intelligent based on harmony search and fuzzy simulation and (3) hybrid intelligent based on harmony search and rough simulation, are... 

    Characteristics of early repolarization pattern in the Iranian population

    , Article Iranian Red Crescent Medical Journal ; Volume 19, Issue 3 , 2017 ; 20741804 (ISSN) Mollazadeh, R ; Sehhati, F ; Eslami, M ; Nemati, F ; Monfarednasab, M ; Sefidbakht, S ; Sharif University of Technology
    Kowsar Medical Publishing Company  2017
    Abstract
    Background: The early repolarization pattern (ERP) has been considered a normal variant in electrocardiography (ECG) for a long time. Nevertheless, increasing evidence has demonstrated its association with adverse outcomes. Objectives: The present study aimed to evaluate the prevalence of ERP in the Iranian general population and demonstrate its clinical and ECG correlates. Methods: A cross sectional study, comprising 1424 consecutive healthy adult individuals, was conducted at two university based hospitals in Tehran, Iran in 2012-2013. The ERP prevalence, clinical characteristics and ECG morphology were investigated in volunteers. Results: ERP was present in 136 out of 1,424 people (9.6%).... 

    On the thermal efficiency of power cycles in finite time thermodynamics

    , Article European Journal of Physics ; Volume 37, Issue 5 , 2016 ; 01430807 (ISSN) Momeni, F ; Morad, M. R ; Mahmoudi, A ; Sharif University of Technology
    Institute of Physics Publishing  2016
    Abstract
    The Carnot, Diesel, Otto, and Brayton power cycles are reconsidered endoreversibly in finite time thermodynamics (FTT). In particular, the thermal efficiency of these standard power cycles is compared to the well-known results in classical thermodynamics. The present analysis based on FTT modelling shows that a reduction in both the maximum and minimum temperatures of the cycle causes the thermal efficiency to increase. This is antithetical to the existing trend in the classical references. Under the assumption of endoreversibility, the relation between the efficiencies is also changed to ηCarnot > ηBrayton > ηDiesel > ηOtto, which is again very different from the corresponding classical... 

    On the Flutter of Swept Taper Wing in Subsonic Compressible Flow Considering Effect of Fuel Sloshing in External Stores

    , M.Sc. Thesis Sharif University of Technology Beheshtinia, Farshad (Author) ; Dehghani Firoozabadi, R (Supervisor)
    Abstract
    In the present work, the aeroelastic stability analysis for the swept taper wing and external fuel tank combination system in subsonic compressible flow are represented. The wing structure is modeled by using the Euler-Bernoulli beam theory. Fuel sloshing is modeled by using an equivalent mechanical mass-spring-damper model. Modal analysis technique is used to drive the structural equations of motion of the system. Aeorodynamic of wing is modeled by using index aerodynamic that has been dived by Marzocca and a slender body aerodynamic theory for the external fuel tank are used. For stability analysis, k-method redrived for a case that structural damping there is. The effects of the external... 

    Nano Structure TiO2 Films by Hybrid PEO-Hydrothermal Method for Dye Sensitised Solar Cell Applications

    , M.Sc. Thesis Sharif University of Technology Shakoorian, Sheida (Author) ; Faghihi-Sani, Mohammad Ali (Supervisor) ; Mohammadpour, R (Co-Advisor)
    Abstract
    This thesis demonstrate a new hybrid Plasma Electrolytic Oxidation (PEO)-Hydrothermal method to produce a nano-structured TiO2 layer over a titanium substrate. Microstructural characterization was carried out by using a FE-SEM to explore nano scale structural changes due to hydrothermal treatment. More over EDS was used to analyse elements of the coating. The FE-SEM images confirmed formation of a 3D network consisting “nano flakes+nano fibers”after 6 or 12 hours and a ”sea urchin like nanostructure+nano fibers” after 24 hour. To improve the performance of nano-structured photoelectrodes, different electrolytes were studied to achieve maximum amount of anatase phase. the best results was... 

    On the equivalency of reliability and security metrics for wireline networks

    , Article Scientia Iranica ; Volume 26, Issue 3 D , 2019 , Pages 1749-1761 ; 10263098 (ISSN) Mojahedian, M. M ; Aref, M. R ; Gohari, A ; Sharif University of Technology
    Sharif University of Technology  2019
    Abstract
    This study considers a secure network coding problem in which some secret keys are shared among legitimate nodes, and there exists an eavesdropper that is able to hear a subset of links. We show the equivalency of secure network coding under weak and strong secrecy conditions. For linear network coding, we show a stronger result: equivalency of "perfect secrecy and zero-error constraints" to "weak secrecy and ϵ-error constraints". This is a secure version of the result obtained by Langberg and Effiros on the equivalence of zero-error and ϵ-error regions in the network coding problem with co-located sources. Jalali and Ho exploited extractor functions to prove the weak and strong rate region... 

    Large-scale changes of the cloud coverage in the ϵ Indi Ba and Bb system

    , Article Monthly Notices of the Royal Astronomical Society ; Volume 495, Issue 4 , May , 2021 , Pages 3881-3899 ; 00358711 (ISSN) Hitchcock, J. A ; Helling, Ch ; Scholz, A ; Hodosan, G ; Dominik, M ; Hundertmark, M ; Jørgensen, U. G ; Longa Peña, P ; Sajadian, S ; Skottfelt, J ; Snodgrass, C ; Bozza, V ; Burgdorf, M. J ; Campbell White, J ; Jaimes, R. F ; Fujii, Y. I ; Haikala, L. K ; Henning, T ; Hinse, T. C ; Lowry, S ; Mancini, L ; Rahvar, S ; Rabus, M ; Southworth, J ; Von Essen, C ; The MiNDSTEp Collaboration ; Sharif University of Technology
    Oxford University Press  2021
    Abstract
    We present the results of 14 nights of I-band photometric monitoring of the nearby brown dwarf binary, ϵ Indi Ba and Bb. Observations were acquired over 2 months, with a total of close to 42 h of coverage at a typically high cadence of 1.4 min. At a separation of just 0.7 arcsec, we do not resolve the individual components, and so effectively treat the binary as if it were a single object. However, ϵ Indi Ba (spectral type T1) is the brightest known T-type brown dwarf, and is expected to dominate the photometric signal. We typically find no strong variability associated with the target during each individual night of observing, but see significant changes in mean brightness – by as much as... 

    Porous eco–friendly fibers for on–line micro solid–phase extraction of nonsteroidal anti–inflammatory drugs from urine and plasma samples

    , Article Journal of Chromatography A ; Volume 1574 , 2018 , Pages 18-26 ; 00219673 (ISSN) Golzari Aqda, T ; Behkami, S ; Bagheri, H ; Sharif University of Technology
    Elsevier B.V  2018
    Abstract
    In this study, cellulose acetate (CA) fibers were prepared using different solvent systems in electrospinning. The recorded scanning electron microscopy micrographs indicated that the morphology of the prepared fibers is closely associated with the type of electrospinning solvents. The prepared CA fibers were used as an extractive phase for on–line micro–solid phase extraction (μ-SPE) of nonsteroidal–inflammatory drugs (NSAIDs) in biological samples pursued by HPLC–UV determination. Work conducted on this research ascertained that the use of dichloromethane:acetone (3:1, v/v) solvent system in the CA dissolution for electrospinning, leads to the formation of porous ribbon–like fibers and... 

    On the existence of 3 -way k-homogeneous Latin trades

    , Article Discrete Mathematics ; Volume 312, Issue 24 , December , 2012 , Pages 3473-3481 ; 0012365X (ISSN) Bagheri Gh., B ; Donovan, D ; Mahmoodian, E. S ; Sharif University of Technology
    2012
    Abstract
    A μ-way Latin trade of volume s is a collection of μ partial Latin squares T1, T2,⋯, Tμ, containing exactly the same s filled cells, such that, if cell (i,j) is filled, it contains a different entry in each of the μ partial Latin squares, and such that row i in each of the μ partial Latin squares contains, set-wise, the same symbols, and column j likewise. It is called a μ-wayk-homogeneous Latin trade if, in each row and each column, Tr, for 1≤r≤μ, contains exactly k elements, and each element appears in Tr exactly k times. It is also denoted as a (μ,k,m) Latin trade, where m is the size of the partial Latin squares. We introduce some general constructions for μ-way k-homogeneous Latin... 

    Core-shell electrospun polybutylene terephthalate/polypyrrole hollow nanofibers for micro-solid phase extraction

    , Article Journal of Chromatography A ; Volume 1434 , 2016 , Pages 19-28 ; 00219673 (ISSN) Bagheri, H ; Rezvani, O ; Banihashemi, S ; Sharif University of Technology
    Elsevier B.V  2016
    Abstract
    In the present work, a new micro-solid phase extraction (μ-SPE) sorbent as an extracting medium based on core-shell nanofibers was synthesized by electrospinning. The core-shell nanofibers of polyvinylpyrrolidone-Polybutylene terephthalate/polypyrrole (PVP-PBT/PPy) were electrospun and subsequently, modified hollow nanofibers were prepared by removing the central PVP moiety. Moreover, conventional PBT/PPy was also prepared for the comparison purposes. The homogeneity and the porous surface structure of the core-shell nanofibers were confirmed by scanning electron microscopy (SEM). The applicability of the fabricated nanofibers-coating was examined by immersed μ-SPE of some selected triazine... 

    Simple fractional order model structures and their applications in control system design

    , Article European Journal of Control ; Volume 16, Issue 6 , 2010 , Pages 680-694 ; 09473580 (ISSN) Tavakoli Kakhki, M ; Haeri, M ; Tavazoei , M. S ; Sharif University of Technology
    2010
    Abstract
    In this paper, firstly a four-parameter fractional order model structure is introduced to approximate processes having S-shaped step responses. Three different strategies are presented in order to determine the parameters of the proposed model. In a special case where the proposed model is not satisfactory, another fractional order model structure with five free parameters is introduced to improve the model approximation. Also in this case, a procedure is provided to estimate the parameters of the introduced five-parameter model. Then, some common classical integer order control design approaches are modified or extended to their fractional order counterparts in order to incorporate the... 

    A constant factor approximation for minimum λ-edge-connected k-subgraph with metric costs

    , Article SIAM Journal on Discrete Mathematics ; Volume 25, Issue 3 , 2011 , Pages 1089-1102 ; 08954801 (ISSN) Safari, M ; Salavatipour, M. R ; Sharif University of Technology
    2011
    Abstract
    In the (k, λ)-subgraph problem, we are given an undirected graph G = (V,E) with edge costs and two positive integers k and λ, and the goal is to find a minimum cost simple λ-edge-connected subgraph of G with at least k nodes. This generalizes several classical problems, such as the minimum cost k-spanning tree problem, or k-MST (which is a (k, 1)-subgraph), and the minimum cost λ-edge-connected spanning subgraph (which is a (|V(G)|, λ)-subgraph). The only previously known results on this problem [L. C. Lau, J. S. Naor, M. R. Salavatipour, and M. Singh, SIAM J. Comput., 39 (2009), pp. 1062-1087], [C. Chekuri and N. Korula, in Proceedings of the IARCS Annual Conference on Foundations of... 

    3-D simulation of mold filling with κ-ε turbulence modeling

    , Article Proceedings of the 14th IASTED International Conference on Applied Simulation and Modelling, Benalmadena, 15 June 2005 through 17 June 2005 ; 2005 , Pages 437-442 ; 0889864691 (ISBN) Shahinfar, S ; Babaei, R ; Asgary, K ; Davami, P ; Hamza M. H ; Sharif University of Technology
    2005
    Abstract
    In this work the SOLA-VOF method was used to solve the Navier-Stokes equations and track the free surface. For modeling the turbulence phenomena in the mold filling κ-ε model was used. In this method solving domain was discreted to three regions includes: laminar sub layer, boundary layer and internal region. The simulation results were shown to be in a good agreement with the experimental results  

    Effect of η phase on mechanical properties of the iron-based superalloy using shear punch testing

    , Article ISIJ International ; Volume 53, Issue 2 , 2013 , Pages 311-316 ; 09151559 (ISSN) Seifollahi, M ; Kheirandish, S ; Razavi, S. H ; Abbasi, S. M ; Sahrapour, P ; Sharif University of Technology
    2013
    Abstract
    In this paper, the shear deformation behavior of A286 Iron-based superalloy was studied with an emphasis on the influence of η phase on shear strength. The η (Ni3Ti phase precipitates at high temperature heat treatment or during services at the expense of gamma prime phase. According to the microstructural features, no evidences of η phase were found at 650 and 720°C. η phase precipitated at 780 and 840°C and the amount of it increased with an increase the time and temperature. Because of using the alloy as fasteners, investigation of shear properties and the influence of η phase on it are indispensable. The shear strength of the alloy with different volume fractions of η was examined. It... 

    The influence of thermal exposure on the γ′ precipitates characteristics and tensile behavior of superalloy IN-738LC

    , Article Journal of Materials Processing Technology ; Volume 147, Issue 3 , 2004 , Pages 343-350 ; 09240136 (ISSN) Sharghi Moshtaghin, R ; Asgari, S ; Sharif University of Technology
    2004
    Abstract
    The effects of long term aging on γ′ size and distribution and its influence on tensile behavior of superalloy IN-738LC at room and in elevated temperatures were investigated. Samples were aged isothermally at 850 °C for different times up to 3000 h and tensile tests were performed on samples in both standard heat treatment (SHT) and aged conditions. For samples in SHT condition yield stress (σy) was independent of tensile temperature up to 550 °C, after which it decreased slightly and then reached a maximum at 650 °C. Also minimum ductility was observed in this temperature. For aged samples, results showed an initial decrease of σy up to 550 °C, followed by a subsequent increase in σy... 

    Evolution of microstructure of nickel base superalloy at high temperatures

    , Article Materials Science and Technology ; Volume 22, Issue 8 , 2006 , Pages 888-898 ; 02670836 (ISSN) Safari, J ; Nategh, S ; McLean, M ; Sharif University of Technology
    2006
    Abstract
    The evolution of primary and secondary γ′ precipitates in the high γ′ volume fraction Rene 80 Ni based superalloy has been examined during aging at elevated temperatures for periods up to 1750 h. While the increase in average dimension of particles followed the cube rate Lifshitz, Slypzof and Wagner (LSW) law, rt-3-r0 -3=kt, there were significant discrepancies between the experimental and theoretical particle size distributions (PSDs) and inconsistency with the kinetic constants associated with the two populations of particles. These differences are attributed to the influence of elastic coherency strains which have not been considered in conventional capillarity driven coarsening models....