Loading...
Search for: roustaei--r
0.108 seconds

    Simulation of low density lipoprotein (LDL) permeation into multilayer coronary arterial wall: interactive effects of wall shear stress and fluid-structure interaction in hypertension

    , Article Journal of Biomechanics ; 2017 ; 00219290 (ISSN) Roustaei, M ; Nikmaneshi, M. R ; Firoozabadi, B ; Sharif University of Technology
    2017
    Abstract
    Due to increased atherosclerosis-caused mortality, identification of its genesis and development is of great importance. Although, key factors of the origin of the disease is still unknown, it is widely believed that cholesterol particle penetration and accumulation in arterial wall is mainly responsible for further wall thickening and decreased rate of blood flow during a gradual progression. To date, various effective components are recognized whose simultaneous consideration would lead to a more accurate approximation of Low Density Lipoprotein (LDL) distribution within the wall. In this research, a multilayer Fluid-Structure Interaction (FSI) model is studied to simulate the penetration... 

    Simulation of low density lipoprotein (LDL) permeation into multilayer coronary arterial wall: interactive effects of wall shear stress and fluid-structure interaction in hypertension

    , Article Journal of Biomechanics ; Volume 67 , 2018 , Pages 114-122 ; 00219290 (ISSN) Roustaei, M ; Nikmaneshi, M. R ; Firoozabadi, B ; Sharif University of Technology
    Elsevier Ltd  2018
    Abstract
    Due to increased atherosclerosis-caused mortality, identification of its genesis and development is of great importance. Although, key factors of the origin of the disease is still unknown, it is widely believed that cholesterol particle penetration and accumulation in arterial wall is mainly responsible for further wall thickening and decreased rate of blood flow during a gradual progression. To date, various effective components are recognized whose simultaneous consideration would lead to a more accurate approximation of Low Density Lipoprotein (LDL) distribution within the wall. In this research, a multilayer Fluid-Structure Interaction (FSI) model is studied to simulate the penetration... 

    Optimization and Scheduling Smart Energy Hub under Uncertainty of Distributed Energy Resources

    , M.Sc. Thesis Sharif University of Technology Roustaei, Mahmoud (Author) ;
    Abstract
    Besides increasing the installation of distributed generation plants, investigating multi-carrier energy systems leads recent studies to focus on Smart Energy Hub (S.E.Hub) systems. S.E.Hub systems incorporate several modules which optimal size and operation of each have already attracted a great deal of research. Uncertainty in the modelling of these modules is an imperative factor that has not been associated in S.E.Hub models properly. To build up a more precise framework for S.E.Hubs, here we present a stochastic model for electricity and natural-gas prices, electricity and heat demands, and emission costs. In this paper, S.E.Hub operates based on minimizing weighted sum function which... 

    Simulation of LDL Permeation into Multilayer Coronary Arterial Wall: Interactive Effects of Wall Shear Stress and Fluid-Structure Interaction in Hypertension

    , M.Sc. Thesis Sharif University of Technology Roustaei, Mehrdad (Author) ; Dehghan Firoozabadi, Bahar (Supervisor)
    Abstract
    Due to increased atherosclerosis-caused mortality, identification of its genesis and development is of great importance. Although, key factors of the origin of the disease is still unknown, it is widely believed that cholesterol particle penetration and accumulation in arterial wall is mainly responsible for further wall thickening and decreased rate of blood flow during a gradual progression. To date, various effective components are recognized whose simultaneous consideration would lead to a more accurate approximation of Low Density Lipoprotein (LDL) distribution within the wall. In this research, a multilayer Fluid-Structure Interaction (FSI) model is studied to simulate the penetration... 

    Parallel Simulation of Generalized Newtonian Flows Using Smoothed Particle Hydrodynamics

    , M.Sc. Thesis Sharif University of Technology Roustaei, Ali (Author) ; Taghizade Manzari, Mehrdad (Supervisor)
    Abstract
    Smoothed Particle Hydrodynamics(SPH) is the oldest Lagrangian method for solving fluid equations. Fluid is approximated with particles that represent a control mass and carry physical properties su as mass, temprature and . . . Simpler formulation relative to other methods like finite volume and finite element, no need for surface traing and ease of adding new physics are benefits of this method. In this method it is necessary to find neighboring particles that are closer than smoothing lenght (h) for ea particle. is is a time consuming operation causing SPH to be a computationaly expensive method. First simulation of Power-law fluids is considered. It has been observed that using of... 

    The addition of data aggregation to SPEED routing algorithm while keeping the functionality of available techniques

    , Article 2nd International Conference on Future Networks, ICFN 2010, 22 January 2010 through 24 January 2010 ; January , 2010 , Pages 349-353 ; 9780769539409 (ISBN) Roustaei, R ; Yousefi Fakhr, F ; Movaghar, A ; Sharif University of Technology
    2010
    Abstract
    Data aggregation is a technique that is used to decrease extra and repetitive data in cluster based routing protocols. As we know SPEED routing algorithm is based on service quality and dose not perform data aggregation. In this article, we try to add an data aggregation technique to the available techniques without interfering with the functions of previous ones. The idea involves virtual configuration of sensors and specification of an individual ID to the created data by the sensors in each region, then data aggregation in relay node is done by this ID, resulting in less energy consumption, lower traffic and repeated data, an increase in network lifetime and better quality of service  

    A new approach to improve quality of service in SPEED routing protocol in wireless sensor network through data aggregation

    , Article 2nd International Conference on Environmental and Computer Science, ICECS 2009, 28 December 2009 through 30 December 2009 ; 2009 , Pages 393-397 ; 9780769539379 (ISBN) Roustaei, R ; Zohrevandi, E ; Hassani, K ; Movaghar, A ; Sharif University of Technology
    2009
    Abstract
    SPEED routing algorithm is a service quality based algorithm in which data aggregation dose not happen. In this article, data aggregation has been added to the conventional technique in SPEED algorithm. The idea involves virtual configuration of sensors and specification of an individual ID to the created data by the sensors in each region, then data aggregation in relay node is done by this ID, resulting in less energy consumption, lower traffic and repeated data, an increase in network lifetime and better quality of service. © 2009 IEEE  

    Perfromnce Invetigation of Eefa Ceram’s Factroty Suppy Chain via SCOR Model

    , M.Sc. Thesis Sharif University of Technology Roustaei Sadrabadi, Ali (Author) ; Eshraghniaye Jahromi, Abdolhamid (Supervisor)
    Abstract
    Tile and ceramic industries plays a vital role in Iran’s economic due to significant added value and to be indigenous concerns. Therefore, in recent years huge investments have been performed by non-governmental agencies in this industry. In spite of high value of investment in this industry, efficient and updated management requires to reach the maximum output of the industry’s potentials. However, in recent years, supply has been exceeded of the demand in national markets. Moreover, the existence of the well-known abroad brands in the international markets has leaded to sever competition’s environment of this industry. In this circumstances, tile and ceramic companies to take the... 

    Preparation and evaluation of various banana-based biochars together with ultra-high performance liquid chromatography-tandem mass spectrometry for determination of diverse pesticides in fruiting vegetables

    , Article Food Chemistry ; Volume 360 , 2021 ; 03088146 (ISSN) Keikavousi Behbahan, A ; Mahdavi, V ; Roustaei, Z ; Bagheri, H ; Sharif University of Technology
    Elsevier Ltd  2021
    Abstract
    Biomass, originates from plant- or animal-based materials with a huge potential to be reused. Here we report a simple, rapid and inexpensive method for preparation of modified biochars derived from the banana peel followed by their applications in pipette-tip micro solid-phase extraction (PT-µSPE). Due to the contribution of various effective parameters on modification of banana peel biochars (BPBs), Taguchi design was used to optimize activation temperature, activation repetition, treatment material and impregnation ratio. Efficiency of the prepared BPBs were studied by extraction of twelve various pesticides, as model analytes with an extended range of log P values (1.4–5.7), followed by... 

    Network vulnerability analysis through vulnerability take-grant model (VTG)

    , Article 7th International Conference on Information and Communications Security, ICICS 2005, Beijing, 10 December 2005 through 13 December 2005 ; Volume 3783 LNCS , 2005 , Pages 256-268 ; 03029743 (ISSN); 3540309349 (ISBN); 9783540309345 (ISBN) Shahriari, H. R ; Sadoddin, R ; Jalili, R ; Zakeri, R ; Omidian, A. R ; Sharif University of Technology
    2005
    Abstract
    Modeling and analysis of information system vulnerabilities helps us to predict possible attacks to networks using the network configuration and vulnerabilities information. As a fact, exploiting most of vulnerabilities result in access rights alteration. In this paper, we propose a new vulnerability analysis method based on the Take-Grant protection model. We extend the initial Take-Grant model to address the notion of vulnerabilities and introduce the vulnerabilities rewriting rules to specify how the protection state of the system can be changed by exploiting vulnerabilities. Our analysis is based on a bounded polynomial algorithm, which generates the closure of the Take-Grant graph... 

    First passage time distribution of chaperone driven polymer translocation through a nanopore: Homopolymer and heteropolymer cases

    , Article Journal of Chemical Physics ; Volume 135, Issue 24 , 2011 ; 00219606 (ISSN) Abdolvahab, R. H ; Metzler, R ; Ejtehadi, M. R ; Sharif University of Technology
    2011
    Abstract
    Combining the advection-diffusion equation approach with Monte Carlo simulations we study chaperone driven polymer translocation of a stiff polymer through a nanopore. We demonstrate that the probability density function of first passage times across the pore depends solely on the Péclet number, a dimensionless parameter comparing drift strength and diffusivity. Moreover it is shown that the characteristic exponent in the power-law dependence of the translocation time on the chain length, a function of the chaperone-polymer binding energy, the chaperone concentration, and the chain length, is also effectively determined by the Péclet number. We investigate the effect of the chaperone size on... 

    Sequence dependence of the binding energy in chaperone-driven polymer translocation through a nanopore

    , Article Physical Review E - Statistical, Nonlinear, and Soft Matter Physics ; Volume 83, Issue 1 , January , 2011 ; 15393755 (ISSN) Abdolvahab, R. H ; Ejtehadi, M. R ; Metzler, R ; Sharif University of Technology
    2011
    Abstract
    We study the translocation of stiff polymers through a nanopore, driven by the chemical-potential gradient exerted by binding proteins (chaperones) on the trans side of the pore. Bound chaperones prevent backsliding through the pore and, therefore, partially rectify the polymer passage. We show that the sequence of chain monomers with different binding affinity for the chaperones significantly affects the translocation dynamics. In particular, we investigate the effect of the nearest-neighbor adjacency probability of the two monomer types. Depending on the magnitude of the involved binding energies, the translocation speed may either increase or decrease with the adjacency probability. We... 

    Reply: Abedpour, asgari, and tabar

    , Article Physical Review Letters ; Volume 106, Issue 20 , 2011 ; 00319007 (ISSN) Abedpour, N ; Asgari, R ; Tabar, M. R. R ; Sharif University of Technology
    2011

    Irreversibility in response to forces acting on graphene sheets

    , Article Physical Review Letters ; Volume 104, Issue 19 , May , 2010 ; 00319007 (ISSN) Abedpour, N ; Asgari, R ; Tabar, M. R. R ; Sharif University of Technology
    2010
    Abstract
    The amount of rippling in graphene sheets is related to the interactions with the substrate or with the suspending structure. Here, we report on an irreversibility in the response to forces that act on suspended graphene sheets. This may explain why one always observes a ripple structure on suspended graphene. We show that a compression-relaxation mechanism produces static ripples on graphene sheets and determine a peculiar temperature Tc, such that for T

    Analysis of design goals of cryptography algorithms based on different components

    , Article Indonesian Journal of Electrical Engineering and Computer Science ; Volume 23, Issue 1 , 2021 , Pages 540-548 ; 25024752 (ISSN) Molk, A.M.N.G ; Aref, M. R ; Khorshiddoust, R. R ; Sharif University of Technology
    Institute of Advanced Engineering and Science  2021
    Abstract
    Cryptography algorithms are a fundamental part of a cryptographic system that is designed and implemented to increase information security. They are the center of attention of experts in the information technology domains. Although the cryptography algorithms are implemented to attain the goals such as confidentially, integrity, and authenticity of designing, but other matters that must be noticed by designers include speed, resource consumption, reliability, flexibility, usage type, and so on. For the useful allocation of hardware, software, and human resources, it is important to identify the role of each of the factors influencing the design of cryptographic algorithms to invest in the... 

    Conservation of statistical results under the reduction of pair-contact interactions to solvation interactions

    , Article Physical Review E - Statistical, Nonlinear, and Soft Matter Physics ; Volume 72, Issue 6 , 2005 ; 15393755 (ISSN) Radja, N.H ; Farzami, R. R ; Ejtehadi, M. R ; Sharif University of Technology
    2005
    Abstract
    We show that the hydrophobicity of sequences is the leading term in Miyazawa-Jernigan interactions. Being the source of additive (solvation) terms in pair-contact interactions, they were used to reduce the energy parameters while resulting in a clear vector manipulation of energy. The reduced (additive) potential performs considerably successful in predicting the statistical properties of arbitrary structures. The evaluated designabilities of the structures by both models are highly correlated. Suggesting geometrically nondegenerate vectors (structures) as proteinlike structures, the additive model is a powerful tool for protein design. Moreover, a crossing point in the log-linear diagram of... 

    Multifunctional hyperelastic structured surface for tunable and switchable transparency

    , Article Applied Sciences (Switzerland) ; Volume 11, Issue 5 , 2021 , Pages 1-11 ; 20763417 (ISSN) Mahabadi, R. K ; Goudarzi, T ; Fleury, R ; Naghdabadi, R ; Sharif University of Technology
    MDPI AG  2021
    Abstract
    We leverage the crucial hyperelastic properties of a multifunctional structured surface to optimize the reconfigurability of the electromagnetic transmission under large nonlinear mechanical deformations. This multiphysics, multifunctional, hyperelastic structured surface (HSS) offers two simultaneous intriguing functionalities; tunability and switchability. It is made of copper reso-nators and a Polydimethylsiloxane (PDMS) substrate, which is one of the most favorable deformable substrates due to its hyperelastic behavior. The proposed HSS is fabricated via an original cost-effective technique and the multiphysics functionalities are captured in both experimental tests and numerical... 

    MaxHiC: A robust background correction model to identify biologically relevant chromatin interactions in Hi-C and capture Hi-C experiments

    , Article PLoS Computational Biology ; Volume 18, Issue 6 , 2022 ; 1553734X (ISSN) Alinejad Rokny, H ; Modegh, R. G ; Rabiee, H. R ; Sarbandi, E. R ; Rezaie, N ; Tam, K. T ; Forrest, A. R. R ; Sharif University of Technology
    Public Library of Science  2022
    Abstract
    Hi-C is a genome-wide chromosome conformation capture technology that detects interactions between pairs of genomic regions and exploits higher order chromatin structures. Conceptually Hi-C data counts interaction frequencies between every position in the genome and every other position. Biologically functional interactions are expected to occur more frequently than transient background and artefactual interactions. To identify biologically relevant interactions, several background models that take biases such as distance, GC content and mappability into account have been proposed. Here we introduce MaxHiC, a background correction tool that deals with these complex biases and robustly... 

    SER of M-PSK modulation in incremental-selective decode-and-forward cooperative communications over Rayleigh fading channels

    , Article International Conference on Advanced Communication Technology, ICACT, 13 February 2011 through 16 February 2011 ; February , 2011 , Pages 432-437 ; 17389445 (ISSN) ; 9788955191554 (ISBN) Renani, R. A ; Saadat, R ; Aref, M. R ; Mirjalily, G ; Sharif University of Technology
    2011
    Abstract
    In this paper we consider a cooperative communication systems over Rayleigh fading channels. The system utilizes a combination of incremental and selective decode-and-forward (ISDF) relaying protocols. The symbol error rate (SER) of M-PSK modulation for the ISDF protocol is derived. Using an approximation of the SER expression, the optimal power allocation is investigated. In order to reduce the complexity of the receiver, we used a modified version of the ISDF protocol which does not use the storage or retransmission of the first phase signal. We also derived optimal power allocation coefficient for modified ISDF. It has been noted that for the optimal power allocation in the ISDF protocol,... 

    Power allocation for incremental-selective decode-and-forward cooperative communications over Rician fading channels

    , Article International Conference on Advanced Communication Technology, ICACT, 13 February 2011 through 16 February 2011 ; February , 2011 , Pages 730-734 ; 17389445 (ISSN) ; 9788955191554 (ISBN) Renani, R. A ; Saadat, R ; Aref, M. R ; Mirjalily, G ; Sharif University of Technology
    2011
    Abstract
    In this paper we consider a relaying communication system over Rician fading channels. In this system we assume simple Incremental-Selective Decode-and-Forward (ISDF) protocol, which is jointly combining incremental and selective DF relaying protocols. In this protocol, storage or retransmission of the first phase signal are not allowed. We analyze the symbol error rate (SER) performance of the recommended protocol with M-PSK modulation. We evaluate the performance of the protocol in the frequency nonselective slow Rician fading channels. Using the approximation of the SER expression, the optimal power allocation is investigated. Our results show that at least 50% of total power must be used...