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An Intrusion Detection System for Wormhole Attack Detection in MANETs
, M.Sc. Thesis Sharif University of Technology ; Movaghar, Ali (Supervisor)
Abstract
Mobile ad hoc networks (MANETs) have been attracting the attention of the researchers in the duration of last years. Because of lack of infrastructure in such networks, all network operations such as routing are done by the nodes themselves. On the other hand, standard MANETs' routing protocols suppose that all nodes are trusted. Thus, these protocols are prone to serious security attack. Wormhole attack is one of the attacks which abuse distributed routing in MANETs. This attack is held between two malicious nodes which are far away from each other. Mentioned nodes introduce themselves as one-hop neighbor of each other. Therefore, they deceive normal nodes and disturb the routing mechanism....
Emerging OCDMA communication systems and data networks [electronic resource]
, Article Journal of Optical Networking ; Volume 6, Issue 9, 1 September 2007, Pages 1138-1178 ; Sharif University Of Technology
Abstract
I present an in-depth review of the trends and the directions taken by researchers worldwide in optical code-division multiple-access (OCDMA) systems. I highlight those trends and features that I believe are essential to the successful introduction of various OCDMA techniques in communication systems and data networks in the near future. In particular I begin by giving a comprehensive review of the construction of optical orthogonal codes (OOCs). Specifically I discuss the recently developed algorithms that are based on matrix algebra, which simplify and enhance the efficiencies of algorithms in OOC generation. In communication systems studies I first focus on and discuss various OCDMA...
A hybrid micro grid islanding detection method
, Article 2013 13th International Conference on Environment and Electrical Engineering, EEEIC 2013 - Conference Proceedings, Wroclaw ; Pages 342-347 , 2013 ; 9781479928026 (ISBN) ; Mahmoodzadeh, Z ; Vakilian, M ; Sharif University of Technology
2013
Abstract
Islanding detection is a great challenge in connecting distributed generation (DG) in electrical power systems. Islanding detection methods are categorized into three groups, i.e., communication based methods, active, and passive methods. Communication based methods are established upon communication between utilities and DGs and have the inconvenience of being expensive and are limited in use. Active methods perturb the system with a disturbance and the system response to the disturbance is analyzed. Although, these methods have small Non Detection Zone, (NDZ) they degrade the power quality. Passive methods monitor one of the grid variables. Their implementation is easy but their NDZ is...
Neuro-fuzzy islanding detection in distributed generation
, Article 2012 IEEE Innovative Smart Grid Technologies - Asia, ISGT Asia 2012, 21 May 2012 through 24 May 2012 ; May , 2012 ; 9781467312219 (ISBN) ; Sheikholeslamzadeh, M ; Ranjbar, A. M ; Mozafari, B ; Sharif University of Technology
2012
Abstract
Islanding detection methods are divided into three main groups as remote, active and passive. Although passive schemes have larger Non Detection Zones (NDZ) relative to other schemes, they are more used in utilities due to their low costs and less PQ problems than other schemes. Passive Schemes are based on the measurements of passive system parameters. These parameters are measured at the point of common coupling (PCC). A new approach in passive techniques is the use of data-mining to classify the system parameters. In this paper, massive indices are collected by simulation of a practical distribution system in PSCAD/EMTP environment. These indices include voltage, frequency, current,...
Low cost concurrent error detection for on-chip memory based embedded processors
, Article Proceedings - 2011 IFIP 9th International Conference on Embedded and Ubiquitous Computing, EUC 2011, 24 October 2011 through 26 October 2011 ; October , 2011 , Pages 114-119 ; 9780769545523 (ISBN) ; Farbeh, H ; Fazeli, M ; Miremadi, S. G ; Sharif University of Technology
Abstract
This paper proposes an efficient concurrent error detection method using control flow checking for embedded processors. The proposed method is based on the co-operation of two hardware modules: 1) an on-chip hardware component to detect branch instructions and generate signatures for the running program, and 2) an external watchdog processor to compare runtime signatures and branch addresses with the information extracted offline. The proposed method is implemented on an embedded processor core and is evaluated by a simulation based statistical fault injection approach where faults are injected into cache and main memory. Experimental results show that the proposed method detects more than...
Determination of antioxidant component and activity of rice bran extract
, Article Scientia Iranica ; Volume 18, Issue 6 , December , 2011 , Pages 1402-1406 ; 10263098 (ISSN) ; Alemzadeh, I ; Maghsoudi, V ; Sharif University of Technology
2011
Abstract
Rice bran is one of the most important co-products in the rice milling. In this research, antioxidant activity of two Iranian rice bran varieties, Fajr and Tarem, extracted by three different solvents (methanol, ethanol and ethyl acetate) was evaluated. The order of antioxidant activity was evaluated by measurement of total phenolic content, antioxidant activity in linoleic acid system, reducing power and scavenging capacity by DPPH radical. The methanolic extract of Fajr rice bran showed a total phenolic content of 3.31 mg Gallic acid/gr rice bran and a DPPH free radical-scavenging activity of 93.91%, achieved at 50 mg/ml concentration, and a percent inhibition of linoleic acid peroxidation...
New drift detection method for data streams
, Article Lecture Notes in Computer Science (including subseries Lecture Notes in Artificial Intelligence and Lecture Notes in Bioinformatics) ; Volume 6943 LNAI , 2011 , Pages 88-97 ; 03029743 (ISSN) ; 9783642238567 (ISBN) ; Beigy, H ; Sharif University of Technology
Abstract
Correctly detecting the position where a concept begins to drift is important in mining data streams. In this paper, we propose a new method for detecting concept drift. The proposed method, which can detect different types of drift, is based on processing data chunk by chunk and measuring differences between two consecutive batches, as drift indicator. In order to evaluate the proposed method we measure its performance on a set of artificial datasets with different levels of severity and speed of drift. The experimental results show that the proposed method is capable to detect drifts and can approximately find concept drift locations
Selected mapping algorithm for PAPR reduction of space-frequency coded OFDM systems without side information
, Article IEEE Transactions on Vehicular Technology ; Volume 60, Issue 3 , 2011 , Pages 1211-1216 ; 00189545 (ISSN) ; Marvasti, F ; Sharif University of Technology
Abstract
Selected mapping (SLM) is a well-known technique for peak-to-average-power ratio (PAPR) reduction of orthogonal frequency-division multiplexing (OFDM) systems. In this technique, different representations of OFDM symbols are generated by rotation of the original OFDM frame by different phase sequences, and the signal with minimum PAPR is selected and transmitted. To compensate for the effect of the phase rotation at the receiver, it is necessary to transmit the index of the selected phase sequence as side information (SI). In this paper, an SLM technique is introduced for the PAPR reduction of space-frequency-block-coded OFDM systems with Alamouti coding scheme. Additionally, a suboptimum...
Bifurcation structure of two coupled FHN neurons with delay
, Article Mathematical Biosciences ; Volume 270 , 2015 , Pages 41-56 ; 00255564 (ISSN) ; Razvan, M ; Sharif University of Technology
Elsevier Inc
2015
Abstract
This paper presents an investigation of the dynamics of two coupled non-identical FitzHugh-Nagumo neurons with delayed synaptic connection. We consider coupling strength and time delay as bifurcation parameters, and try to classify all possible dynamics which is fairly rich. The neural system exhibits a unique rest point or three ones for the different values of coupling strength by employing the pitchfork bifurcation of non-trivial rest point. The asymptotic stability and possible Hopf bifurcations of the trivial rest point are studied by analyzing the corresponding characteristic equation. Homoclinic, fold, and pitchfork bifurcations of limit cycles are found. The delay-dependent stability...
Marker-free detection of instruments in laparoscopic images to control a cameraman robot
, Article Proceedings of the ASME Design Engineering Technical Conference, 15 August 2010 through 18 August 2010 ; Volume 3, Issue PARTS A AND B , 2010 , Pages 477-482 ; 9780791844113 (ISBN) ; Mirbagheri, A ; Farahmand, F ; Bagheri, S ; Sharif University of Technology
Abstract
Assistant robots are widely used in laparoscopic surgery to facilitate the camera holding and manipulation task. A variety of a hands-free operator interfaces have been implemented for user control of the robots, including voice commands, foot pedals, and eye and head motion tracking systems. This paper proposes a novel user control interface, based on processing of the laparoscopic images, that enables the robot to automatically adjust the view of the laparoscopic camera without disturbing the surgeon's concentration. An effective marker-free detection method was investigated to track the instrument position in the laparoscopic images in real time so that the robot could center the...
Health monitoring of structures using few frequency response measurements
, Article Scientia Iranica ; Volume 17, Issue 6 A , NOVEMBER-DECEMBER , 2010 , Pages 493-500 ; 10263098 (ISSN) ; Kianian, M ; Ghodrati, E ; Sharif University of Technology
2010
Abstract
The development of damage detection techniques for offshore jacket structures is vital for preventing catastrophic events. This paper applies a frequency response based method for the purpose of structural health monitoring. In this approach, the concept of a minimum rank perturbation theory is used. The feasibility of using a finite number of sensors and its effect on damage detection capabilities is investigated. In addition, the performance of the proposed method is evaluated in the case of multiple damages. The aforementioned points are illustrated using the numerical study of a two dimensional jacket platform
Joint multi-user interference and clipping noise cancellation in uplink MC-CDMA system
, Article AEU - International Journal of Electronics and Communications ; Volume 64, Issue 5 , 2010 , Pages 425-432 ; 14348411 (ISSN) ; Azmi, P ; Marvasti, F ; Sharif University of Technology
Abstract
In this paper, an iterative method is proposed to jointly cancel multi-user interference and clipping noise in uplink Multi-Carrier Code Division Multiple Access (MC-CDMA) systems. Clipping is the simplest method to overcome high peak-to-average power ratio of multi-carrier signals but it makes the signals distorted. Reconstruction methods use non-distorted samples to reconstruct distorted samples in the receiver but multi-user interference causes the methods do not work properly because all the received samples are distorted due to clipping and interference and so there is no undistorted samples to be used in recovering clipped samples. On the other hand, multi-user interference...
AdaBoost-based face detection in color images with low false alarm
, Article ICCMS 2010 - 2010 International Conference on Computer Modeling and Simulation, 22 January 2010 through 24 January 2010, Sanya ; Volume 2 , 2010 , Pages 107-111 ; 9780769539416 (ISBN) ; Kasaei, S ; Sharif University of Technology
2010
Abstract
In this paper, we have proposed a new face detection method which combines the AdaBoost algorithm with skin color information and support vector machine (SVM). First, a cascade classifier based on AdaBoost is used to detect faces in images. Due to noise and illumination changes some nonfaces might be detected too, therefore we have used a skin color model in the YCbCr color space to remove some of the detected nonfaces. Finally, we have utilized SVM to detect faces more accurately. Experimental results show that the performance of the proposed method is higher than the basic AdaBoost in the sense of detecting fewer nonfaces
XABA: A zero-knowledge anomaly-based behavioral analysis method to detect insider threats
, Article 13th International ISC Conference on Information Security and Cryptology, 7 September 2016 through 8 September 2016 ; 2016 , Pages 26-31 ; 9781509039494 (ISBN) ; Nowroozi, A. R ; Jalili, R ; Sharif University of Technology
Institute of Electrical and Electronics Engineers Inc
Abstract
Insider threat is a significant security risk for organizations and hard to detect. Most introduced detection methods need contextual data entries about users, or preprocessed user activity logs to detect insider threats which it is costly and time-consuming. In this paper, we introduce a behavior analysis method that learns its context and detects multiple types of insider threats from raw logs and network traffic in real-time. This method, named XABA, learns user roles and exclusive behaviors, through analyzing raw logs related to each network session of the user. Then it checks for some abnormal patterns, and if so, triggers the appropriate alert. XABA is implemented on the big-stream...
Fast fault detection method for modular multilevel converter semiconductor power switches
, Article IET Power Electronics ; Volume 9, Issue 2 , 2016 , Pages 165-174 ; 17554535 (ISSN) ; Khodabandeh, M ; Zolghadri, M. R ; Sharif University of Technology
Institution of Engineering and Technology
2016
Abstract
This study proposes a new fault detection method for modular multilevel converter (MMC) semiconductor power switches. While in common MMCs, the cells capacitor voltages are measured directly for control purposes, in this study voltage measurement point changes to the cell output terminal improving fault diagnosis ability. Based on this measurement reconfiguration, a novel fault detection algorithm is designed for MMCs semiconductor power switches. The open circuit and short circuit faults are detected based on unconformity between modules output voltage and switching signals. Simulation and experimental results confirm accurate and fast operation of the proposed method in faulty cell...
Union of low-rank subspaces detector
, Article IET Signal Processing ; Volume 10, Issue 1 , 2016 , Pages 55-62 ; 17519675 (ISSN) ; Ahmadi, P ; Sadeghi, M ; Rahnavard, N ; Sharif University of Technology
Institution of Engineering and Technology
Abstract
The problem of signal detection using a flexible and general model is considered. Owing to applicability and flexibility of sparse signal representation and approximation, it has attracted a lot of attention in many signal processing areas. In this study, the authors propose a new detection method based on sparse decomposition in a union of subspaces model. Their proposed detector uses a dictionary that can be interpreted as a bank of matched subspaces. This improves the performance of signal detection, as it is a generalisation for detectors. Low-rank assumption for the desired signals implies that the representations of these signals in terms of some proper bases would be sparse. Their...
Trojan counteraction in hardware: A survey and new taxonomy
, Article Indian Journal of Science and Technology ; Volume 9, Issue 18 , 2016 ; 09746846 (ISSN) ; Manzuri Shalmani, M. T ; Hemmatyar, A. M. A ; Sharif University of Technology
Indian Society for Education and Environment
2016
Abstract
The widespread expansion of the semiconductor industry and various production phases have led to the increased importance of fabricating highly secure chips. Both in factories manufacturing and later at actual operation, digital integrated circuits (IC) might encounter a variety of hardware attacks, one type of which involves Hardware Trojans (HT). Due to their diversity, it has become a major hardware security challenge to prevent, detect and track down HTs. In this regard, the first step is to understand the taxonomy of Trojans and the current ways in which they can be encountered. For that purpose, certain classifications are required. With their downsized dimensions, the Trojans have...
Power quality comparison of active islanding detection methods in a single phase PV grid connected inverter
, Article IEEE International Symposium on Industrial Electronics, 5 July 2009 through 8 July 2009 ; 2009 , Pages 1852-1857 ; 9781424443499 (ISBN) ; Mokhtari, H ; Sharif University of Technology
Abstract
In this paper, the power quality of a single-phase photovoltaic grid connected inverter when uses active islanding detection methods is investigated. Two main groups of these methods are analyzed in this paper. The main focus is on the output power quality of PV sources for these methods. Also the variation of output current THD, while the output power changes, is explored. The variation of output current THD is measured when the parameters of active islanding detection method are changed, and the limitation of these parameters for complying power quality standards in the nominal output power is detected. ©2009 IEEE
Moiré deflectometry-based position detection for optical tweezers
, Article Optics Letters ; Volume 42, Issue 17 , 2017 , Pages 3506-3509 ; 01469592 (ISSN) ; Nader, S ; Reihani, S ; Tavassoly, M. T ; Sharif University of Technology
Abstract
Optical tweezers have proven to be indispensable tools for pico-Newton range force spectroscopy. A quadrant photodiode (QPD) positioned at the back focal plane of an optical tweezers’ condenser is commonly used for locating the trapped object. In this Letter, for the first time, to the best of our knowledge, we introduce a moiré pattern-based detection method for optical tweezers. We show, both theoretically and experimentally, that this detection method could provide considerably better position sensitivity compared to the commonly used detection systems. For instance, position sensitivity for a trapped 2.17 μm polystyrene bead is shown to be 71% better than the commonly used QPD-based...
Hardware trojan detection based on logical testing
, Article Journal of Electronic Testing: Theory and Applications (JETTA) ; Volume 33, Issue 4 , 2017 , Pages 381-395 ; 09238174 (ISSN) ; Manzuri Shalmani, M. T ; Hemmatyar, A. M. A ; Sharif University of Technology
Springer New York LLC
2017
Abstract
In recent years, hardware Trojans (HTs) have become one of the main challenging concerns within the chain of manufacturing digital integrated circuit chips. Because of their diversity in chips, HTs are difficult to detect and locate. This paper attempted to propose a new improved method for detection and localization of HTs based on the real-time logical values of nodes. The algorithm extracts the nodes with special attributes. At the next stage, the nodes with the greatest similarity in terms of logical value are selected as targets. Depending on the size of the circuit, the extraction continues until a sufficient number of similar nodes has been selected. The logical relationship between...