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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....
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...
Weakly compressible SPH simulation of cnoidal waves with strong plunging breakers
, Article Ocean Dynamics ; Volume 69, Issue 6 , 2019 , Pages 657-678 ; 16167341 (ISSN) ; Pak, A ; Sharif University of Technology
Springer Verlag
2019
Abstract
Hydrodynamics of highly nonlinear cnoidal waves and their subsequent strong plunging breakers are among the least understood and most significant issues in coastal engineering. In this work, a weakly compressible smoothed particle hydrodynamics (SPH) formulation is used for the study of the generation and propagation of cnoidal waves and investigation of the characteristics of the induced strong plunging breakers. Numerical results show the capability of the SPH scheme for properly simulating the cnoidal waves. For the case of strong plunging breakers, dynamic and kinematic features of the flow are computed and compared with certain implementations of other numerical techniques. SPH is shown...
Water repellent room temperature vulcanized silicone for enhancing the long-term stability of perovskite solar cells
, Article Solar Energy ; Volume 218 , 2021 , Pages 28-34 ; 0038092X (ISSN) ; Heydari, M ; Mohammadi, M ; Parand, P ; Taghavinia, N ; Sharif University of Technology
Elsevier Ltd
2021
Abstract
A key direction toward enhancing the long term and outdoor stability of the perovskite solar cells is encapsulation. As a result, a suitable encapsulation package is required to prevent moisture and oxygen penetration toward the perovskite solar cells. In this work, a low-cost commercially available bilayer structure of poly (methyl methacrylate)/ room-temperature vulcanizing silicone rubber (RTV) encapsulation package for enhancing the long term stability of the perovskite solar cells has been investigated. Encapsulated cells retained more than 80% of the initial efficiency at the environmental condition of 50% moisture, and room temperature after 1000 h, however reference cell efficiency...
Wardrop's first principle: Extension for capacitated networks
, Article Scientia Iranica ; Volume 28, Issue 1 , 2021 , Pages 175-191 ; 10263098 (ISSN) ; Poorzahedy, H ; Nourinejad, M ; Sharif University of Technology
Sharif University of Technology
2021
Abstract
In transportation literature, User Equilibrium (UE) has been widely studied since early 1950's, many studies of which define equilibrium flow of traffic for uncapacitated networks based on Wardrop's first principle, implying also a Nash Equilibrium (NE). Although, in general, the two equilibria (UE and NE) are not explicitly the same, they are shown to be equivalent under special conditions for uncapacitated UE, when volume delay functions are separable, continuous, non-decreasing and non-negative. A good deal of research is devoted to explain UE in capacitated networks based on Wardrop's first principle and the concept of generalized costs. However, UE for capacitated networks, even under...
Wardrop's first principle: Extension for capacitated networks
, Article Scientia Iranica ; Volume 28, Issue 1 , 2021 , Pages 175-191 ; 10263098 (ISSN) ; Poorzahedy, H ; Nourinejad, M ; Sharif University of Technology
Sharif University of Technology
2021
Abstract
In transportation literature, User Equilibrium (UE) has been widely studied since early 1950's, many studies of which define equilibrium flow of traffic for uncapacitated networks based on Wardrop's first principle, implying also a Nash Equilibrium (NE). Although, in general, the two equilibria (UE and NE) are not explicitly the same, they are shown to be equivalent under special conditions for uncapacitated UE, when volume delay functions are separable, continuous, non-decreasing and non-negative. A good deal of research is devoted to explain UE in capacitated networks based on Wardrop's first principle and the concept of generalized costs. However, UE for capacitated networks, even under...
Utilizing the moiré deflectometry-based detection method improves the detection sensitivity for gold nanoparticles trapped by optical tweezers
, Article Journal of the Optical Society of America B: Optical Physics ; Volume 38, Issue 7 , 2021 , Pages 2135-2140 ; 07403224 (ISSN) ; Khorshad, A. A ; Sharif University of Technology
The Optical Society
2021
Abstract
Gold nanoparticles (GNPs) are very often used as handles for nanotechnological micromanipulation. In this regard, optical trapping of GNPs is of great importance, in which locating the trapped GNP within the focal spot with nanometer precision is crucial. Very recently, we have introduced a new position detection system for optical tweezers based on moiré deflectometry (MD). Here we show, both theoretically and experimentally, that an MD detection system could provide significantly larger detection sensitivity for a trapped GNP compared to that provided by conventional back focal plane (BFP) detection systems. For instance, for a trapped 200 nm GNP, the detection sensitivity provided by the...
Use of a hybrid wind—solar—diesel—battery energy system to power buildings in remote areas: A case study
, Article Sustainability (Switzerland) ; Volume 13, Issue 16 , 2021 ; 20711050 (ISSN) ; Hosseini Dehshiri, S. S ; Hosseini Dehshiri, S. J ; Mostafaeipour, A ; Issakhov, A ; Techato, K ; Sharif University of Technology
MDPI
2021
Abstract
The emerging environmental consequences of overdependence on fossil fuels have pushed many countries to invest in clean and renewable sources of power. Countries like Iran where these sources can be found in abundance can take advantage of this potential to reduce their dependence on fossil fuels. This study investigated the feasibility of the standalone use of a hybrid renewable energy system (HRES) to power buildings in the Bostegan village in the Hormozgan province of Iran. Technical, economic, and environmental assessments were performed with the help of the Hybrid Optimization of Multiple Energy Resources (HOMER) software, and the optimal configuration for the system components was...
Use of a hybrid wind—solar—diesel—battery energy system to power buildings in remote areas: a case study
, Article Sustainability (Switzerland) ; Volume 13, Issue 16 , 2021 ; 20711050 (ISSN) ; Hosseini Dehshiri, S ; Hosseini Dehshiri, J ; Mostafaeipour, A ; Issakhov, A ; Techato, K ; Sharif University of Technology
MDPI
2021
Abstract
The emerging environmental consequences of overdependence on fossil fuels have pushed many countries to invest in clean and renewable sources of power. Countries like Iran where these sources can be found in abundance can take advantage of this potential to reduce their dependence on fossil fuels. This study investigated the feasibility of the standalone use of a hybrid renewable energy system (HRES) to power buildings in the Bostegan village in the Hormozgan province of Iran. Technical, economic, and environmental assessments were performed with the help of the Hybrid Optimization of Multiple Energy Resources (HOMER) software, and the optimal configuration for the system components was...
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...
Turn-off chelation-enhanced fluorescence sensing of carbon dot-metallic deep eutectic solvent by imidazole-based small molecules
, Article Sensors and Actuators B: Chemical ; Volume 344 , 2021 ; 09254005 (ISSN) ; Bagheri, H ; Es-haghi, A ; Sharif University of Technology
Elsevier B.V
2021
Abstract
Low accuracy, requirement of expensive instruments, derivatization and multi-step sample preparation, inconsistencies during the fabrication process, time-consuming procedures and utilization of eco-unfriendly chemicals are some limitations of various developed methods for detection of 4-methylimidazol (4-MeI). Herein, a rapid and miniaturized fluorescent probe based on the ultrasound‒assisted formation of carbon dots (CDs) in a metallic deep eutectic solvent (MDES) was developed and conveniently implemented to detect 4-MeI in commercial dark soft drinks. In-situ synthesis of CDs-chelated metals in the presence of the target analyte facilitates a kinetically fluorescence emission with no...
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...
Trichloroethylene degradation by PVA-coated calcium peroxide nanoparticles in Fe(II)-based catalytic systems: enhanced performance by citric acid and nanoscale iron sulfide
, Article Environmental Science and Pollution Research ; Volume 28, Issue 3 , 2021 , Pages 3121-3135 ; 09441344 (ISSN) ; Shan, A ; Sun, Y ; Gu, X ; Lyu, S ; Zhou, Y ; Sharif University of Technology
Springer Science and Business Media Deutschland GmbH
2021
Abstract
In this study, the enhanced trichloroethylene (TCE) degradation performance was investigated by polyvinyl alcohol coated calcium peroxide nanoparticles (PVA@nCP) as an oxidant in Fe(II)-based catalytic systems. The nanoscale iron sulfide (nFeS), having an average particle size of 115.4 nm, was synthesized in the laboratory and characterized by SEM, TEM, HR-TEM along with EDS elemental mapping, XRD, FTIR, ICP-OES, and XPS techniques. In only ferrous iron catalyzed system (PVA@nCP/Fe(II)), TCE degradation was recorded at 58.9% in 6 h. In comparison, this value was increased to 97.5% or 99.7% with the addition of citric acid (CA) or nFeS in PVA@nCP/Fe(II) system, respectively. A comparative...
Trichloroethylene degradation by PVA-coated calcium peroxide nanoparticles in Fe(II)-based catalytic systems: enhanced performance by citric acid and nanoscale iron sulfide
, Article Environmental Science and Pollution Research ; Volume 28, Issue 3 , 2021 , Pages 3121-3135 ; 09441344 (ISSN) ; Shan, A ; Sun, Y ; Gu, X ; Lyu, S ; Zhou, Y ; Sharif University of Technology
Springer Science and Business Media Deutschland GmbH
2021
Abstract
In this study, the enhanced trichloroethylene (TCE) degradation performance was investigated by polyvinyl alcohol coated calcium peroxide nanoparticles (PVA@nCP) as an oxidant in Fe(II)-based catalytic systems. The nanoscale iron sulfide (nFeS), having an average particle size of 115.4 nm, was synthesized in the laboratory and characterized by SEM, TEM, HR-TEM along with EDS elemental mapping, XRD, FTIR, ICP-OES, and XPS techniques. In only ferrous iron catalyzed system (PVA@nCP/Fe(II)), TCE degradation was recorded at 58.9% in 6 h. In comparison, this value was increased to 97.5% or 99.7% with the addition of citric acid (CA) or nFeS in PVA@nCP/Fe(II) system, respectively. A comparative...
SVNN: an efficient PacBio-specific pipeline for structural variations calling using neural networks
, Article BMC Bioinformatics ; Volume 22, Issue 1 , 2021 ; 14712105 (ISSN) ; Hadadian Nejad Yousefi, M ; Goudarzi, M ; Sharif University of Technology
BioMed Central Ltd
2021
Abstract
Background: Once aligned, long-reads can be a useful source of information to identify the type and position of structural variations. However, due to the high sequencing error of long reads, long-read structural variation detection methods are far from precise in low-coverage cases. To be accurate, they need to use high-coverage data, which in turn, results in an extremely time-consuming pipeline, especially in the alignment phase. Therefore, it is of utmost importance to have a structural variation calling pipeline which is both fast and precise for low-coverage data. Results: In this paper, we present SVNN, a fast yet accurate, structural variation calling pipeline for PacBio long-reads...
SVNN: an efficient PacBio-specific pipeline for structural variations calling using neural networks
, Article BMC Bioinformatics ; Volume 22, Issue 1 , 2021 ; 14712105 (ISSN) ; Hadadian Nejad Yousefi, M ; Goudarzi, M ; Sharif University of Technology
BioMed Central Ltd
2021
Abstract
Background: Once aligned, long-reads can be a useful source of information to identify the type and position of structural variations. However, due to the high sequencing error of long reads, long-read structural variation detection methods are far from precise in low-coverage cases. To be accurate, they need to use high-coverage data, which in turn, results in an extremely time-consuming pipeline, especially in the alignment phase. Therefore, it is of utmost importance to have a structural variation calling pipeline which is both fast and precise for low-coverage data. Results: In this paper, we present SVNN, a fast yet accurate, structural variation calling pipeline for PacBio long-reads...
Simultaneous determination of gas–water relative permeability and capillary pressure from steady-state corefloods
, Article Journal of Hydrology ; Volume 598 , 2021 ; 00221694 (ISSN) ; Hemmati, N ; Behr, A ; Genolet, L ; Mahani, H ; Zeinijahromi, A ; Bedrikovetsky, P ; Sharif University of Technology
Elsevier B.V
2021
Abstract
For traditional calculations of relative phase permeability (Kr) from coreflood Steady-State Test (SST), the capillary pressure (Pc) is required. Usually, Pc is determined from a separate test, using a centrifuge or porous-plate methods. However, during SSTs, water cut and pressure drop are measured during the transition period between two sequential fractional-flow steps. We developed a novel method for simultaneous determination of Kr and Pc from SST by using both steady-state and transient data. In the proposed method, the transition data on the pressure drop across the core are used instead of the traditionally utilised Pc-curve. The main idea is that the stabilisation period during each...
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...
Sb2S3 and Cu3SbS4 nanocrystals as inorganic hole transporting materials in perovskite solar cells
, Article Solar Energy ; Volume 223 , 2021 , Pages 106-112 ; 0038092X (ISSN) ; Heidariramsheh, M ; Javadpour, S ; Ghavaminia, E ; Mahdavi, S. M ; Taghavinia, N ; Sharif University of Technology
Elsevier Ltd
2021
Abstract
One of the key parts of perovskite solar cells which has great influence on their performance and stability is hole transporting layer. Spiro-OMeTAD is extensively used as organic hole transporting material in perovskite solar cells. However, Spiro-OMeTAD is expensive and has low chemical stability. In this study, the solution processed Sb2S3 and Cu3SbS4 nanocrystals have been synthesized and then the n-i-p mesoscopic perovskite solar cells have been fabricated using Spiro-OMeTAD, Sb2S3 and Cu3SbS4 nanocrystals as hole transporting layer at ambient air condition. It is shown that the conduction and valence band levels of the synthesized Sb2S3 and Cu3SbS4 nanocrystals are in the proper...
Sagittal range of motion of the thoracic spine using standing digital radiography: A throughout comparison with non-radiographic data reviewed from the literature
, Article Scientia Iranica ; Volume 26, Issue 3B , 2019 , Pages 1307-1315 ; 10263098 (ISSN) ; Arjmand, N ; Sharif University of Technology
Sharif University of Technology
2019
Abstract
Previous studies have measured thoracic Range of Motion (RoM) using either skin-mounted devices or supine CT-imaging and have reported on quite different RoMs. Given the inherent shortcomings of measurements of vertebrae movements from the overlying skin, the present study aims to measure normal RoM of the thoracic spine in the sagittal plane using the upright digital radiography. Lateral radiographs of the thoracic spine were obtained from eight asymptomatic male subjects in upright standing and full forward flexion using a mobile U-arm digital radiographic system. Total (T1-T12), upper (T1-T6), and lower (T6-T12) thoracic RoMs were measured. A throughout comparison of available skin-based...