Loading...
Search for:
detection-method
0.017 seconds
Total 90 records
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....
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...
Non-Destructive estimation of physicochemical properties and detection of ripeness level of apples using machine vision
, Article International Journal of Fruit Science ; Volume 22, Issue 1 , 2022 , Pages 628-645 ; 15538362 (ISSN) ; Nadimi, M ; Abbaspour Gilandeh, Y ; Paliwal, J ; Sharif University of Technology
Taylor and Francis Ltd
2022
Abstract
Nondestructive estimation of physicochemical properties, post-harvest physiology, and level of ripeness of fruits is essential to their automated harvesting, sorting, and handling. Recent research efforts have identified machine vision systems as a promising noninvasive nondestructive tool for exploring the relationship between physicochemical and appearance characteristics of fruits at various ripening levels. In this regard, the purpose of the current study is to provide an intelligent algorithm for estimating two physical properties including firmness, and soluble solid content (SSC), three chemical properties viz. starch, acidity, and titratable acidity (TA), as well as detection of the...
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...
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...
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...
Fast detection of open-switch fault in cascaded H-bridge multilevel converter
, Article Scientia Iranica ; Volume 25, Issue 3D , 2018 , Pages 1561-1570 ; 10263098 (ISSN) ; Zolghadri, M. R ; Khodabandeh, M ; Ouni, S ; Sharif University of Technology
Sharif University of Technology
2018
Abstract
Cascaded H-bridge converter has been utilized recently in different high-power applications due to its modular and simple structure. In order to have a balanced operation after a fault occurrence in this converter, it is necessary to detect the switch fault and its location. In this paper, a fast power-switch fault detection method is presented to identify a fault and its location. Only one voltage measurement per phase is required by this method, and the fault detection is faster compared to the existing methods. Moreover, it is suitable for implementation on an FPGA device due to the use of simple math, relational, and state machine blocks. The proposed method is verified by computer...
Analysis of nonlinear acoustic wave propagation in HIFU treatment using westervelt equation
, Article Scientia Iranica ; Volume 25, Issue 4 , 2018 , Pages 2087-2097 ; 10263098 (ISSN) ; Ahmadian, M. T ; Sharif University of Technology
Sharif University of Technology
2018
Abstract
Currently, the HIFU (High-Intensity Focused Ultrasound) therapy method is known as one of the most advanced surgical techniques of tumor ablation therapy. Simulation of the non-linear acoustic wave and tissue interaction is essential in HIFU planning to improve the usefulness and efficiency of treatment. In this paper, linear, thermoviscous, and nonlinear equations are applied using two different media: liver and water. Transducer power of 8.3-134 Watts with the frequency of 1.1 MHz is considered as the range of study to analyze the interaction of wave and tissue. Results indicate that the maximum focal pressure of about 0.5-4.3 MPa can be achieved for transducer power rates of 8.3 to 134 W....
Localizing exception faults in Android applications
, Article Scientia Iranica ; Volume 26, Issue 3 D , 2019 , Pages 1567-1588 ; 10263098 (ISSN) ; Heydarnoori, A ; Sharif University of Technology
Sharif University of Technology
2019
Abstract
In software programs, most of the time, there is a chance for occurrence of faults in general, and exception faults in particular. Localizing those pieces of code that are responsible for a particular fault is one of the most complicated tasks, and it can produce incorrect results if done manually. Semi-automated and fully-automated techniques have been introduced to overcome this issue. However, despite recent advances in fault localization techniques, they are not necessarily applicable to Android applications because of their special characteristics such as context-awareness, use of sensors, being executable on various mobile devices, limited hardware resources, etc. To this aim, in this...
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...
An efficient hardware implementation for a motor imagery brain computer interface system
, Article Scientia Iranica ; Volume 26, Issue 1 , 2019 , Pages 72-94 ; 10263098 (ISSN) ; Mohammadzade, H ; Chamanzar, A. R ; Shabany, M ; Ghojogh, B ; Sharif University of Technology
Sharif University of Technology
2019
Abstract
Brain Computer Interface (BCI) systems, which are based on motor imagery, enable humans to command artificial peripherals by merely thinking about the task. There is a tremendous interest in implementing BCIs on portable platforms, such as Field Programmable Gate Arrays (FPGAS) due to their low-cost, low-power and portability characteristics. This article presents the design and implementation of a Brain Computer Interface (BCI) system based on motor imagery on a Virtex-6 FPGA. In order to design an accurate algorithm, the proposed method avails statistical learning methods such as Mutual Information (MI), Linear Discriminant Analysis (LDA), and Support Vector Machine (SVM). It also uses...
Online nonlinear structural damage detection using hilbert Huang transform and artificial neural networks
, Article Scientia Iranica ; Volume 26, Issue 3A , 2019 , Pages 1266-1279 ; 10263098 (ISSN) ; Bakhshi, A ; Bahar, O ; Sharif University of Technology
Sharif University of Technology
2019
Abstract
In order to implement a damage detection strategy and assess the condition of a structure, Structural Health Monitoring (SHM) as a process plays a key role in structural reliability. This paper aims to present a methodology for online detection of damages that may occur during a strong ground excitation. In this regard, Empirical Mode Decomposition (EMD) is superseded by Ensemble Empirical Mode Decomposition (EEMD) in the Hilbert Huang Transformation (HHT). Although analogous with EMD, EEMD brings about more appropriate Intrinsic Mode Functions (IMFs). IMFs are employed to assess the first-mode frequency and mode shape. Afterwards, Artificial Neural Network (ANN) is applied to predict story...
Localizing exception faults in Android applications
, Article Scientia Iranica ; Volume 26, Issue 3 D , 2019 , Pages 1567-1588 ; 10263098 (ISSN) ; Heydarnoori, A ; Sharif University of Technology
Sharif University of Technology
2019
Abstract
In software programs, most of the time, there is a chance for occurrence of faults in general, and exception faults in particular. Localizing those pieces of code that are responsible for a particular fault is one of the most complicated tasks, and it can produce incorrect results if done manually. Semi-automated and fully-automated techniques have been introduced to overcome this issue. However, despite recent advances in fault localization techniques, they are not necessarily applicable to Android applications because of their special characteristics such as context-awareness, use of sensors, being executable on various mobile devices, limited hardware resources, etc. To this aim, in this...
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...
An efficient hardware implementation for a motor imagery brain computer interface system
, Article Scientia Iranica ; Volume 26, Issue 1 , 2019 , Pages 72-94 ; 10263098 (ISSN) ; Mohammadzade, H ; Chamanzar, A ; Shabany, M ; Ghojogh, B ; Sharif University of Technology
Sharif University of Technology
2019
Abstract
Brain Computer Interface (BCI) systems, which are based on motor imagery, enable humans to command artificial peripherals by merely thinking about the task. There is a tremendous interest in implementing BCIs on portable platforms, such as Field Programmable Gate Arrays (FPGAS) due to their low-cost, low-power and portability characteristics. This article presents the design and implementation of a Brain Computer Interface (BCI) system based on motor imagery on a Virtex-6 FPGA. In order to design an accurate algorithm, the proposed method avails statistical learning methods such as Mutual Information (MI), Linear Discriminant Analysis (LDA), and Support Vector Machine (SVM). It also uses...
Online nonlinear structural damage detection using hilbert huang transform and artificial neural networks
, Article Scientia Iranica ; Volume 26, Issue 3A , 2019 , Pages 1266-1279 ; 10263098 (ISSN) ; Bakhshi, A ; Bahar, O ; Sharif University of Technology
Sharif University of Technology
2019
Abstract
In order to implement a damage detection strategy and assess the condition of a structure, Structural Health Monitoring (SHM) as a process plays a key role in structural reliability. This paper aims to present a methodology for online detection of damages that may occur during a strong ground excitation. In this regard, Empirical Mode Decomposition (EMD) is superseded by Ensemble Empirical Mode Decomposition (EEMD) in the Hilbert Huang Transformation (HHT). Although analogous with EMD, EEMD brings about more appropriate Intrinsic Mode Functions (IMFs). IMFs are employed to assess the first-mode frequency and mode shape. Afterwards, Artificial Neural Network (ANN) is applied to predict story...
Direct introduction of semicon layers in a cable model
, Article Scientia Iranica ; Volume 15, Issue 2 , 2008 , Pages 203-210 ; 10263098 (ISSN) ; Vakilian, M ; Sharif University of Technology
Sharif University of Technology
2008
Abstract
The detection and location of any Partial Discharge (PD) signal requires an accurate frequency dependent cable model to correctly simulate the PD signal attenuation during its propagation in the cable. This model should be capable of simulating the semiconducting layers, which have significant effects on PD signal attenuation and its propagation velocity. There is a substantial need for improvements in the flexibility of the transient cable model through direct introduction of the two semiconducting layers in the cable model. This can be employed in the next step to develop a 3-phase cable model for ATP. This paper has derived an impedance formula for the semiconducting layers. The...
GLR detector for coded signals in noise and interference
, Article Scientia Iranica ; Volume 15, Issue 2 , 2008 , Pages 170-174 ; 10263098 (ISSN) ; Derakhtian, M ; Nayebi, M. M ; Aref, M. R ; Sharif University of Technology
Sharif University of Technology
2008
Abstract
In this paper, the detection of a coded signal in additive white Gaussian noise and the interference is studied, where there is no knowledge about the correlation between the received symbols and about the noise and interference parameters. The Maximum Likelihood (ML) estimates of the unknown parameters are found, they are substituted in the probability density functions of the observation and the Generalized Likelihood Ratio (GLR) detector is derived. This detector can also be used for the activity detection of a signal in unknown Inter-Symbol Interference (ISI). In this case, the interference is modeled as the unknown correlation between the received symbols. Simulation examples are...
Detection of a band-limited signal using an orthonormal, fully-decimated filter-bank
, Article Scientia Iranica ; Volume 14, Issue 6 , 2007 , Pages 555-565 ; 10263098 (ISSN) ; Tadaion, A. A ; Nayebi, M. M ; Aref, M. R ; Sharif University of Technology
Sharif University of Technology
2007
Abstract
In this paper, two methods are proposed for the detection of a band-limited signal in unknown variance white Gaussian noise. The complex amplitude and the frequency of the signal and the noise variance are assumed as unknown parameters. Using wavelet concepts, an orthonormal, fully-decimated filter-bank is employed to decompose the signal into its subband components. It is shown that, in this process, the noise is also decomposed into orthonormal zero-mean components. In the output, if a band-limited target signal is present, the respective single subband component (or two components in marginal cases) containing the target signal presents a non-zero mean. The presence of a non-zero mean...