Loading...
Search for: farhat--pooneh
0.048 seconds

    Towards blind detection of low-rate spatial embedding in image steganalysis

    , Article IET Image Processing ; Volume 9, Issue 1 , 2015 , Pages 31-42 ; 17519659 (ISSN) Farhat, F ; Ghaemmaghami, S ; Sharif University of Technology
    Institution of Engineering and Technology  2015
    Abstract
    Steganalysis of least significant bit (LSB) embedded images in spatial domain has been investigated extensively over the past decade and most well-known LSB steganography methods have been shown to be detectable. However, according to the latest findings in the area, two major issues of very low-rate (VLR) embedding and content-adaptive steganography have remained hard to resolve. The problem of VLR embedding is indeed a generic problem to any steganalyser, while the issue of adaptive embedding specifically depends on the hiding algorithm employed. The latter challenge has recently been brought up again to the area of LSB steganalysis by highly undetectable stego image steganography that... 

    Fabrication of low friction bronze-graphite nano-composite coatings

    , Article Materials and Design ; Volume 32, Issue 6 , 2011 , Pages 3548-3553 ; 02641275 (ISSN) Nickchi, T ; Ghorbani, M ; Alfantazi, A ; Farhat, Z ; Sharif University of Technology
    2011
    Abstract
    This paper addresses the fabrication of bronze-nano-graphite coatings containing 30. nm sized graphite particles. Addition of Poly Vinyl Pyrrolidone (PVP) and dispersing the suspension by ultrasound was utilized to stabilize the electroplating solution. Pulsed current electrodeposition was used and the deposits were characterized in terms of graphite content, particle dispersion in coating and morphology. The wear behavior of the coating was compared to bronze-micro-graphite coatings prepared with the same experimental conditions. The present coating showed improved wear resistance in comparison to bronze-micro-graphite coatings at the same graphite content  

    Elasto-plastic finite element simulation of asymmetrical plate rolling using an ALE approach

    , Article Journal of Materials Processing Technology ; Volume 177, Issue 1-3 , 2006 , Pages 525-529 ; 09240136 (ISSN) Farhat-Nia, F ; Salimi, M ; Movahhedy, M. R ; Sharif University of Technology
    2006
    Abstract
    Asymmetric sheet rolling is simulated by using an elastic-plastic arbitrary Lagrangian-Eulerian (ALE) finite element method. The ALE finite element approach easily predicts the curvature development due to inequality in work roll/plate surface finish (interface friction) and speed mismatch. An isotropic work hardening material is assumed. Reasonable agreements were found between the numerical method and the experimental results. © 2006 Elsevier B.V. All rights reserved  

    Effect of Doping of La in Pr Site and Cu/Fe in Ni site on Crystal Structure, Oxygen Non-stoichiometry level and Electrical Conductivity of Pr2NiO4 as Intermediate Temperature Solid Oxide Fuel Cell Cathode

    , M.Sc. Thesis Sharif University of Technology Farhat, Pooneh (Author) ; Faghihi Sani, Mohammad Ali (Supervisor)
    Abstract
    Nowadays, one of the most important research goals is to develop intermediate-temperature solid oxide fuel cells (IT-SOFC) operated at 500–800 °C. However, the large cathode polarization resistance caused by the reduced temperature is a major barrier against such an urgent demand for commercialization. In this regard, it is necessary to select a proper material as a cathode working efficiently at reduced temperatures without losing its desired performance. Various mixed ionic electron conductors (MIECs), especially Ruddlesden–Popper-type oxides, are used to improve the cathode performance at intermediate temperatures. Among these layered oxides, Pr2NiO4 has been reported to possess the... 

    Multi-dimensional correlation steganalysis

    , Article MMSP 2011 - IEEE International Workshop on Multimedia Signal Processing ; 2011 ; 9781457714337 (ISBN) Farhat, F ; Diyanat, A ; Ghaemmaghami, S ; Aref, M. R ; Sharif University of Technology
    2011
    Abstract
    Multi-dimensional spatial analysis of image pixels have not been much investigated for the steganalysis of the LSB Steganographic methods. Pixel distribution based steganalysis methods could be thwarted by intelligently compensating statistical characteristics of image pixels, as reported in several papers. Simple LSB replacement methods have been improved by introducing smarter LSB embedding approaches, e.g. LSB matching and LSB+ methods, but they are basically the same in the sense of the LSB alteration. A new analytical method to detect LSB stego images is proposed in this paper. Our approach is based on the relative locations of image pixels that are essentially changed in an LSB... 

    Locally multipath adaptive routing protocol resilient to selfishness and wormholes

    , Article Lecture Notes in Computer Science (including subseries Lecture Notes in Artificial Intelligence and Lecture Notes in Bioinformatics), 12 May 2010 through 13 May 2010 ; Volume 6047 LNCS , May , 2010 , Pages 187-200 ; 03029743 (ISSN) ; 9783642128264 (ISBN) Farhat, F ; Pakravan, M. R ; Salmasizadeh, M ; Aref, M. R ; Sharif University of Technology
    2010
    Abstract
    Locally multipath adaptive routing (LMAR) protocol, classified as a new reactive distance vector routing protocol for MANETs is proposed in this paper. LMAR can find an ad-hoc path without selfish nodes and wormholes using a random search algorithm in polynomial-time. Also when the primary path fails, it discovers an alternative safe path if network graph remains connected after eliminating selfish/malicious nodes. The main feature of LMAR to seek safe route free of selfish and malicious nodes in polynomial time is its searching algorithm and flooding stage that its generated traffic is equiloaded compared to single-path routing protocols but its ability to bypass the attacks is much better... 

    Image Steganalysis of Low Rate Embedding in Spatial Domain

    , Ph.D. Dissertation Sharif University of Technology Farhat, Farshid (Author) ; Ghaemmaghami, Shahrokh (Supervisor) ; Aref, Mohammad Reza (Co-Advisor)
    Abstract
    LSB embedding in spatial domain with very low rate can be easily performed and its detection in spite of many researches is very hard, while BOSS competition has been held to break an adaptive embedding algorithm with low rate. Thus, proposing powerful steganalyzer of very low rate in spatial domain is highly requested. In this thesis it has been tried to present some algorithms to detect secret message with very low rate in spatial domain using eigenvalues analysis and relative auto-correlation of image.First approach is based on the analysis of the eigenvalues of the cover correlation matrix that we used for the first time. Image partitioning, correlation function computation,...