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Full-Text Articles in Computer Engineering

Increasing Key Space At Little Extra Cost In Rfid Authentications, Gökhan Dalkiliç, Mehmet Hi̇lal Özcanhan, Hafi̇ze Şen Çakir Jan 2014

Increasing Key Space At Little Extra Cost In Rfid Authentications, Gökhan Dalkiliç, Mehmet Hi̇lal Özcanhan, Hafi̇ze Şen Çakir

Turkish Journal of Electrical Engineering and Computer Sciences

Traditional authentication and key establishment protocols utilize nonce parameters as a means for message freshness, recent aliveness, and key derivation. Improving identity verification, increasing key space, or making secret updates more complex through nonces are not goals. Generating random numbers as nonces and not making the most out of them can be considered as a loss in resource stricken radio frequency identification (RFID) tags. By increasing the shared secrets slightly, a new functionality for the nonces is introduced, which makes the authentication and key establishment protocols of RFID systems more secure, in general. The proposed method contributes to the security …


A Low-Memory Intensive Decoding Architecture For Double-Binary Convolutional Turbo Code, Ming Zhan, Liang Zhou, Jun Wu Jan 2014

A Low-Memory Intensive Decoding Architecture For Double-Binary Convolutional Turbo Code, Ming Zhan, Liang Zhou, Jun Wu

Turkish Journal of Electrical Engineering and Computer Sciences

Memory accesses take a large part of the power consumption in the iterative decoding of double-binary convolutional turbo code (DB-CTC). To deal with this, a low-memory intensive decoding architecture is proposed for DB-CTC in this paper. The new scheme is based on an improved maximum a posteriori probability algorithm, where instead of storing all of the state metrics, only a part of these state metrics is stored in the state metrics cache (SMC), and the memory size of the SMC is thus reduced by 25%. Owing to a compare-select--recalculate processing (CSRP) module in the proposed decoding architecture, the unstored state …


Spatiotemporal Realization Of An Artificial Retina Model And Performance Evaluation Through Isi- And Spike Count-Based Image Reconstruction Methods, İrfan Karagöz, Mustafa Özden Jan 2014

Spatiotemporal Realization Of An Artificial Retina Model And Performance Evaluation Through Isi- And Spike Count-Based Image Reconstruction Methods, İrfan Karagöz, Mustafa Özden

Turkish Journal of Electrical Engineering and Computer Sciences

Development of an artificial retina model that can mimic the biologic retina is a highly challenging task and this task is an important step in the development of a visual prosthesis. The receptive field structure of the retina layer is usually modeled as a 2D difference of Gaussian (DOG) filter profile. In the present study, as a different approach, a retina model including a 3D 2-stage DOG filter (3D-ADOG) that has an adaptively changing bandwidth with respect to the local image statistic is developed. Using this modeling, the adaptive image processing of the retina can be realized. The contribution of …


A Penalty Function Method For Designing Efficient Robust Classifiers With Input Space Optimal Separating Surfaces, Ayşegül Uçar, Yakup Demi̇r, Cüneyt Güzeli̇ş Jan 2014

A Penalty Function Method For Designing Efficient Robust Classifiers With Input Space Optimal Separating Surfaces, Ayşegül Uçar, Yakup Demi̇r, Cüneyt Güzeli̇ş

Turkish Journal of Electrical Engineering and Computer Sciences

This paper considers robust classification as a constrained optimization problem. Where the constraints are nonlinear, inequalities defining separating surfaces, whose half spaces include or exclude the data depending on their classes and the cost, are used for attaining robustness and providing the minimum volume regions specified by the half spaces of the surfaces. The constraints are added to the cost using penalty functions to get an unconstrained problem for which the gradient descent method can be used. The separating surfaces, which are aimed to be found in this way, are optimal in the input data space in contrast to the …


Applications Of Wavelets And Neural Networks For Classification Of Power System Dynamics Events, Samir Avdakovic, Amir Nuhanovic, Mirza Kusljugic, Elvisa Becirovic Jan 2014

Applications Of Wavelets And Neural Networks For Classification Of Power System Dynamics Events, Samir Avdakovic, Amir Nuhanovic, Mirza Kusljugic, Elvisa Becirovic

Turkish Journal of Electrical Engineering and Computer Sciences

This paper investigates the possibility of classifying power system dynamics events using discrete wavelet transform (DWT) and a neural network (NN) by analyzing one variable at a single network bus. Following a disturbance in the power system, it will propagate through the system in the form of low-frequency electromechanical oscillations (LFEOs) in a frequency range of up to 5 Hz. DWT allows the identification of components of the LFEO, their frequencies, and magnitudes. After determining the energy components' share of the analyzed signal using DWT and Parseval's theorem, the input data for the classification process using a NN are obtained. …


Design, Optimization, And Realization Of A Wire Antenna With A 25:1 Bandwidth Ratio For Terrestrial Communications, Korkut Yeği̇n Jan 2014

Design, Optimization, And Realization Of A Wire Antenna With A 25:1 Bandwidth Ratio For Terrestrial Communications, Korkut Yeği̇n

Turkish Journal of Electrical Engineering and Computer Sciences

Wire antennas can be made wideband if the antenna is loaded with passive elements and connected to a lossless matching network. However, realization of the load component values and matching network can easily become impractical. In this study, using only a surface mount and standard component values, antenna loads and a matching network are optimized using genetic algorithms. The optimized design achieves a 25:1 bandwidth ratio, from 20 MHz to 500 MHz, with a maximum voltage standing wave ratio (VSWR) of 3.5 and minimum system gain of --5 dBi. The antenna system gain at azimuth is taken as the objective …


A New Method For Extraction Of Speech Features Using Spectral Delta Characteristics And Invariant Integration, Hassan Farsi, Samana Kuhimoghadam Jan 2014

A New Method For Extraction Of Speech Features Using Spectral Delta Characteristics And Invariant Integration, Hassan Farsi, Samana Kuhimoghadam

Turkish Journal of Electrical Engineering and Computer Sciences

We propose a new feature extraction algorithm that is robust against noise. Nonlinear filtering and temporal masking are used for the proposed algorithm. Since the current automatic speech recognition systems use invariant-integration and delta-delta techniques for speech feature extraction, the proposed algorithm improves speech recognition accuracy appropriately using a delta-spectral feature instead of invariant integration. One of the nonenvironmental factors that reduce recognition accuracy is the vocal tract length (VTL), leading to a mismatch between the training and testing data. We can use the invariant-integration feature idea for decreasing the VTL effects. The aim of this paper is to provide …


Continuity Of Currents Across Neighboring Cells In Pmm Analysis Of Thin-Wire Grids, Sena Esen Bayer Keski̇n, Ahmet Ari̇f Ergi̇n Jan 2014

Continuity Of Currents Across Neighboring Cells In Pmm Analysis Of Thin-Wire Grids, Sena Esen Bayer Keski̇n, Ahmet Ari̇f Ergi̇n

Turkish Journal of Electrical Engineering and Computer Sciences

This article presents a new approach for the analysis of electromagnetic scattering from a rectangular wire mesh. In this sense, a basis function that considers the flow of a current from one cell to the next is proposed in light of Floquet's theorem. The proposed basis function enables the use of periodic method of moments in frequency-selective surfaces composed of thin wires in the case of a system having a connection with neighboring cells, such as thin-wire grids. The validity of the proposed solution approach is tested in 2 distinct cases (with and without a neighbor connection) for scattered fields. …


Neuro-Fuzzy Network Approach For Modeling Submicron Mosfets: Application To Mosfet Subcircuit Simulation, Amirhossein Abdollahinohoji, Fardad Farokhi, Majid Zamani Jan 2014

Neuro-Fuzzy Network Approach For Modeling Submicron Mosfets: Application To Mosfet Subcircuit Simulation, Amirhossein Abdollahinohoji, Fardad Farokhi, Majid Zamani

Turkish Journal of Electrical Engineering and Computer Sciences

A neuro-fuzzy network approach is developed to model the nonlinear behavior of submicron metal-oxide semiconductor field-effect transistors (MOSFETs). The proposed model is trained and implemented as a MOSFET in a software environment. The training data are obtained through various simulations of a MOSFET Berkeley short channel insulated-gate field-effect transistor model 3 (BSIM3) in HSPICE, and the trained model is utilized to simulate the MOSFET device. The obtained result shows good and noticeable agreement between the numerical result of the original model in HSPICE and the neuro-fuzzy approach in the device and subcircuit modeling.


Simultaneous Identification And Correction Of Measurement And Branch Parameter Errors, Mehdi Ahmadi Jirdehi, Mehrdad Tarafdar Hagh, Kazem Zare Jan 2014

Simultaneous Identification And Correction Of Measurement And Branch Parameter Errors, Mehdi Ahmadi Jirdehi, Mehrdad Tarafdar Hagh, Kazem Zare

Turkish Journal of Electrical Engineering and Computer Sciences

The performance of the state estimation (SE) depends on the accuracy of the received measured data, as well as the parameter data of the power system. In this paper, a new algorithm is proposed for the simultaneous identification and correction of measurement and branch parameter errors (series and shunt admittances) in the power system SE problem. The proposed method uses Lagrange multipliers for the identification and correction of branch parameter errors without the need for a-priori specification of suspect parameter vectors. Erroneous measurements and branch parameter values can be corrected using the proposed method to estimate the measurement and branch …


Fuzzy Impedance And Force Control Of A Stewart Platform, Selçuk Ki̇zi̇r, Zafer Bi̇ngül Jan 2014

Fuzzy Impedance And Force Control Of A Stewart Platform, Selçuk Ki̇zi̇r, Zafer Bi̇ngül

Turkish Journal of Electrical Engineering and Computer Sciences

A new, simple, and effective control method is proposed for the position-based impedance and force control of a Stewart platform (SP). The control approach can be divided into 3 parts, namely position control in free space, impedance control in contact, and force control. An impedance filter is developed to achieve the desired behavior between the position and force. The gain of the filter is modified by a fuzzy logic proportional-integral-derivative controller. Kinematic and dynamic models of the SP are simulated in a MATLAB/Simulink environment. Several real-time experiments are conducted with the SP developed in our laboratory. The results of the …


Fuzzy Logic Approach To Henry Factor For Distributed Feedback Laser Case, Abdullah Çavuşoğlu Jan 2014

Fuzzy Logic Approach To Henry Factor For Distributed Feedback Laser Case, Abdullah Çavuşoğlu

Turkish Journal of Electrical Engineering and Computer Sciences

In this study, a simple approach for intelligent modeling of the Henry factor (\alpha-alpha parameter, antiguiding factor, phase-amplitude coupling factor) or the so-called linewidth enhancement factor, which is an actual analysis and design parameter for semiconductor laser diodes and optical communication systems, is proposed based on the fuzzy logic (FL) phenomenon. The proposed FL-based model easily computes the Henry factor in terms of different wavelengths and injection current levels (i.e. the inputs of the model). The experimental data belong to a distributed feedback laser, obtained from amplified spontaneous emission spectra, which is among the techniques required for the characterization of …


New Throughput-Based Antenna Selection Scheme, Mohammad Lari, Abbas Mohammadi, Abdolali Abdipour Jan 2014

New Throughput-Based Antenna Selection Scheme, Mohammad Lari, Abbas Mohammadi, Abdolali Abdipour

Turkish Journal of Electrical Engineering and Computer Sciences

In this paper, a new throughput-based transmit antenna selection (AS) scheme is evaluated. First, a closed-form solution for the throughput rate of a multiple-input multiple-output (MIMO) system, with a truncated selective repeat automatic repeat request (TSR-ARQ) or selective repeat plus go-back-N automatic repeat request (SR+GBN-ARQ) protocol at the data link layer, is proposed. In addition, a throughput-based AS technique with adaptive modulation is also investigated. For this purpose, the throughput and packet error rates of a MIMO system with a transmit AS and TSR-ARQ protocol at the data link layer are analyzed. This study is conducted in 2 different cases. …


A Novel Hybrid Recurrent Wavelet Neural Network Control Of Permanent Magnet Synchronous Motor Drive For Electric Scooter, Chih Hong Lin Jan 2014

A Novel Hybrid Recurrent Wavelet Neural Network Control Of Permanent Magnet Synchronous Motor Drive For Electric Scooter, Chih Hong Lin

Turkish Journal of Electrical Engineering and Computer Sciences

Due to the electric scooter with nonlinear uncertainties, e.g., nonlinear friction force of the transmission belt, the linear controller was made to disable speed tracking control. In order to overcome this problem, a novel hybrid recurrent wavelet neural network (NHRWNN) control system is proposed to control for a permanent-magnet synchronous motor-driven electric scooter in this study. The NHRWNN control system consists of a supervised control, a recurrent wavelet neural network (RWNN), and a compensated control with adaptive law. According to the Lyapunov stability theorem and the gradient descent method, the on-line parameter training methodology of the RWNN can be derived …


An Artificial Neural Network Approach For Sensorless Speed Estimation Via Rotor Slot Harmonics, Hayri̇ Arabaci Jan 2014

An Artificial Neural Network Approach For Sensorless Speed Estimation Via Rotor Slot Harmonics, Hayri̇ Arabaci

Turkish Journal of Electrical Engineering and Computer Sciences

In this paper, a sensorless speed estimation method with an artificial neural network for squirrel cage induction motors is presented. Motor current is generally used for sensorless speed estimation. Rotor slot harmonics are available in the frequency spectrum of the current. The frequency components of these determined harmonics are used to estimate the speed of the motor in which the number of rotor slots is given. In the literature, individual algorithms have been used to calculate the speed from the slot harmonics. Unlike the literature, in the proposed method, an artificial neural network is used to extract the speed from …


New Approach Using Structure-Based Modeling For The Simulation Of Real Power/Frequency Dynamics In Deregulated Power Systems, Mostafa Eidiani, Hossein Zeynal Jan 2014

New Approach Using Structure-Based Modeling For The Simulation Of Real Power/Frequency Dynamics In Deregulated Power Systems, Mostafa Eidiani, Hossein Zeynal

Turkish Journal of Electrical Engineering and Computer Sciences

Load frequency control (LFC) is one of the significant ancillary services in the electricity markets. The major concerns with LFC models have long been their dynamic response and complexity, as well as market price sensitivity. To cater to the complexity of the dynamic model that is introduced by the LFC and algebraic constraints by the transmission network, the differential-algebraic equation is transformed into a set of ordinary differential equations. This is done by differentiating the network constraints under a certain assumption that can be held throughout the system. To make the model suitable in a market environment, the real power …


Design And Realization Of A Welding Oscillator, Muci̇z Özcan Jan 2014

Design And Realization Of A Welding Oscillator, Muci̇z Özcan

Turkish Journal of Electrical Engineering and Computer Sciences

Welding is one of the most popular methods to combine metal pieces in manufacturing processes. Arc welding, among all welding techniques, is the most commonly used in manufacturing due to its cost and flexibility. During the manufacturing process, arc welding is either performed by an operator or by automatic tools such as welding oscillators. Using automatic tools has advantages over manual use, as the process will be faster, cheaper, and have less welding flaws. In this paper, a homemade welding oscillator and the method to manufacture it are presented. The presented welding oscillator can be manufactured for a very low …


Comparison Of Ais And Fuzzy C-Means Clustering Methods On The Classification Of Breast Cancer And Diabetes Datasets, Seral Özşen, Rahi̇me Ceylan Jan 2014

Comparison Of Ais And Fuzzy C-Means Clustering Methods On The Classification Of Breast Cancer And Diabetes Datasets, Seral Özşen, Rahi̇me Ceylan

Turkish Journal of Electrical Engineering and Computer Sciences

Data reduction is an indispensable part of pattern classification processes in many cases. If the number of samples is excessive, sample reduction or data reduction algorithms can be used for an effective processing time and reliable successive results. Many methods have been used for data reduction. Fuzzy c-means is one of these methods and it is widely used in such applications as clustering algorithms. In this study, we applied a different clustering algorithm, an artificial immune system (AIS), for the data reduction process. We realized the performance evaluation experiments on the standard Chainlink and Iris datasets, while the main application …


Horizontal Dilution Of Precision-Based Ultra-Wideband Positioning Technique For Indoor Environments, Kerem Küçük Jan 2014

Horizontal Dilution Of Precision-Based Ultra-Wideband Positioning Technique For Indoor Environments, Kerem Küçük

Turkish Journal of Electrical Engineering and Computer Sciences

Ultra-wideband (UWB) technology provides considerable performance in many indoor localization problems thanks to its very wide spectrum and high-resolution characteristics. In this paper, we propose using the horizontal dilution of precision (HDOP) to decrease the localization error in indoor environments for UWB localization systems. To achieve this aim, first we determine the positioning accuracy of a commercially available UWB positioning system using laboratory experiments. Next, the results of the position estimations obtained by the HDOP are compared with the experimental results acquired by the UWB positioning system. Finally, we investigate a detailed comparison with the least squares (LS), nonlinear regression …


A New Approach Of Nonblind Watermarking Methods Based On Dwt And Svd Via Lu Decomposition, Onur Jane, Ersi̇n Elbaşi Jan 2014

A New Approach Of Nonblind Watermarking Methods Based On Dwt And Svd Via Lu Decomposition, Onur Jane, Ersi̇n Elbaşi

Turkish Journal of Electrical Engineering and Computer Sciences

Multimedia security has been the focal point of considerable research activity in the last decade, mainly because of its wide application area. Watermarking, in particular, is identified as a major technology to achieve copyright protection and multimedia security. Therefore, recent studies in the literature include some evident approaches for embedding data into a multimedia element. Because of its useful frequency component separation, the discrete wavelet transform (DWT) is commonly used in watermarking schemes. Moreover, singular value decomposition (SVD) and lower-and-upper (LU) decomposition have little effect on the perception of the watermark. Therefore, in this study, a combination of DWT and …


Implementation Of Neural Network-Based Maximum Power Tracking Control For Wind Turbine Generators, Abdulhaki̇m Karakaya, Ercüment Karakaş Jan 2014

Implementation Of Neural Network-Based Maximum Power Tracking Control For Wind Turbine Generators, Abdulhaki̇m Karakaya, Ercüment Karakaş

Turkish Journal of Electrical Engineering and Computer Sciences

In this study, the maximum power point tracking (MPPT) of a permanent magnet synchronous generator used in a wind generator system is realized by a prototype installed in a laboratory environment. The installed prototype is modeled in a MATLAB/Simulink environment. The MPPT is realized by an artificial neural network (ANN). The obtained simulation and experimental results are compared. The maximum power estimation at various windmill speeds (rpm) of the trained ANN in determined reference speeds is analyzed. The zero crossing points of the phases are determined by a digital signal peripheral interface controller and the system is operated according to …


Design And Implementation Of A Microcontroller Based Wind Energy Conversion System, Mehmet Demi̇rtaş, Şeri̇f Şerefoğlu Jan 2014

Design And Implementation Of A Microcontroller Based Wind Energy Conversion System, Mehmet Demi̇rtaş, Şeri̇f Şerefoğlu

Turkish Journal of Electrical Engineering and Computer Sciences

In this study, a dsPIC-controlled DC/DC boost converter and a wind turbine control system that tracks the maximum power point are designed and implemented. In practice, the energy generated by a permanent magnet synchronous wind turbine is applied to the load using a circuit that consists of a rectifier, boost converter, and protective load. The converter operates in the designed mode 35% more efficiently than in the normal operation mode. In addition, the wind turbine is protected from overvoltages in strong windy weather using the protective circuit. Experimental results show that the ripple value on the direct current belonging to …


Optimization Of Job Shop Scheduling Problems Using Modified Clonal Selection Algorithm, Yilmaz Atay, Hali̇fe Kodaz Jan 2014

Optimization Of Job Shop Scheduling Problems Using Modified Clonal Selection Algorithm, Yilmaz Atay, Hali̇fe Kodaz

Turkish Journal of Electrical Engineering and Computer Sciences

Artificial immune systems (AISs) are one of the artificial intelligence techniques studied a lot in recent years. AISs are based on the principles and mechanisms of the natural immune system. In this study, the clonal selection algorithm, which is used commonly in AISs, is modified. This algorithm is applied to job shop scheduling problems, which are one of the most difficult optimization problems. For applying application results to the optimum solution, parameter values giving the optimum solution are determined by analyzing the parameters in the algorithm. The obtained results are given in detail in the tables and figures. The best …


Study On Interior Permanent Magnet Synchronous Motors For Hybrid Electric Vehicle Traction Drive Application Considering Permanent Magnet Type And Temperature, Javad Soleimani, Abolfazl Vahedi, Abdolhossein Ejlali, Mohammadhossein Barzegari Bafghi Jan 2014

Study On Interior Permanent Magnet Synchronous Motors For Hybrid Electric Vehicle Traction Drive Application Considering Permanent Magnet Type And Temperature, Javad Soleimani, Abolfazl Vahedi, Abdolhossein Ejlali, Mohammadhossein Barzegari Bafghi

Turkish Journal of Electrical Engineering and Computer Sciences

Recently, interior permanent magnet synchronous motors (Interior-PMSMs) have become known as a good candidate for hybrid electric vehicle (HEV) traction drive application due to their unique merits. However, the dynamic and steady-state behaviors of these motors are quite dependent on the permanent magnet (PM) type, configuration, and volume in rotor structures. This paper uses a novel structure of Interior-PMSMs for traction applications with fragmental buried rotor magnets in order to achieve low torque ripple, iron losses, and cogging torque. In this paper, first, the effect of the PM type on a d-q equivalent circuit model is examined. Next, the design …


A New Psfb Converter-Based Inverter Arc Welding Machine With High Power Density And High Efficiency, İsmai̇l Aksoy Jan 2014

A New Psfb Converter-Based Inverter Arc Welding Machine With High Power Density And High Efficiency, İsmai̇l Aksoy

Turkish Journal of Electrical Engineering and Computer Sciences

In this study, a high-performance single-phase inverter arc welding machine is presented. Power control of the developed welding machine is realized with a high-frequency, phase-shifted full bridge (PSFB) pulse-width modulation (PWM) converter. The PSFB PWM converter operates with soft switching at no load and full load. There is no need to use a passive snubber in the converter. Welding machine control is implemented with a digital signal processor (DSP) and phase-shift PWM IC. By means of the DSP, advanced arc welding functions and protection features such as short-circuit, over-current, and temperature protection are achieved. The current and voltage waveforms given …


A Proof-Theoretic Semantic Analysis Of Dynamic Epistemic Logic, Sabine Frittella, Giuseppe Greco, Alexander Kurz, Alessandra Palmigiano, Vlasta Sikimić Jan 2014

A Proof-Theoretic Semantic Analysis Of Dynamic Epistemic Logic, Sabine Frittella, Giuseppe Greco, Alexander Kurz, Alessandra Palmigiano, Vlasta Sikimić

Engineering Faculty Articles and Research

The present paper provides an analysis of the existing proof systems for dynamic epistemic logic from the viewpoint of proof-theoretic semantics. Dynamic epistemic logic is one of the best known members of a family of logical systems which have been successfully applied to diverse scientific disciplines, but the proof theoretic treatment of which presents many difficulties. After an illustration of the proof-theoretic semantic principles most relevant to the treatment of logical connectives, we turn to illustrating the main features of display calculi, a proof-theoretic paradigm which has been successfully employed to give a proof-theoretic semantic account of modal and substructural …


Book Review: The Basics Of Digital Forensics: The Primer For Getting Started In Digital Forensics, Stephen Larson Jan 2014

Book Review: The Basics Of Digital Forensics: The Primer For Getting Started In Digital Forensics, Stephen Larson

Journal of Digital Forensics, Security and Law

The Basics of Digital Forensics: The Primer for Getting Started in Digital Forensics is well-named–it really is very basic. And it should be, as the book’s intended audience includes entry-level digital forensics professionals and complimentary fields such as law enforcement, legal, and general information security. Though the copyright is 2012, some of the data is from 2009, and there is mention of estimates for 2010.


“Time For Some Traffic Problems”: Enhancing E-Discovery And Big Data Processing Tools With Linguistic Methods For Deception Detection, Erin S. Crabb Jan 2014

“Time For Some Traffic Problems”: Enhancing E-Discovery And Big Data Processing Tools With Linguistic Methods For Deception Detection, Erin S. Crabb

Journal of Digital Forensics, Security and Law

Linguistic deception theory provides methods to discover potentially deceptive texts to make them accessible to clerical review. This paper proposes the integration of these linguistic methods with traditional e-discovery techniques to identify deceptive texts within a given author’s larger body of written work, such as their sent email box. First, a set of linguistic features associated with deception are identified and a prototype classifier is constructed to analyze texts and describe the features’ distributions, while avoiding topic-specific features to improve recall of relevant documents. The tool is then applied to a portion of the Enron Email Dataset to illustrate how …


Hot Zone Identification: Analyzing Effects Of Data Sampling On Spam Clustering, Rasib Khan, Mainul Mizan, Ragib Hasan, Alan Sprague Jan 2014

Hot Zone Identification: Analyzing Effects Of Data Sampling On Spam Clustering, Rasib Khan, Mainul Mizan, Ragib Hasan, Alan Sprague

Journal of Digital Forensics, Security and Law

Email is the most common and comparatively the most efficient means of exchanging information in today's world. However, given the widespread use of emails in all sectors, they have been the target of spammers since the beginning. Filtering spam emails has now led to critical actions such as forensic activities based on mining spam email. The data mine for spam emails at the University of Alabama at Birmingham is considered to be one of the most prominent resources for mining and identifying spam sources. It is a widely researched repository used by researchers from different global organizations. The usual process …


Accurate Modeling Of The Siemens S7 Scada Protocol For Intrusion Detection And Digital Forensics, Amit Kleinmann, Avishai Wool Jan 2014

Accurate Modeling Of The Siemens S7 Scada Protocol For Intrusion Detection And Digital Forensics, Amit Kleinmann, Avishai Wool

Journal of Digital Forensics, Security and Law

The Siemens S7 protocol is commonly used in SCADA systems for communications between a Human Machine Interface (HMI) and the Programmable Logic Controllers (PLCs). This paper presents a model-based Intrusion Detection Systems (IDS) designed for S7 networks. The approach is based on the key observation that S7 traffic to and from a specific PLC is highly periodic; as a result, each HMI-PLC channel can be modeled using its own unique Deterministic Finite Automaton (DFA). The resulting DFA-based IDS is very sensitive and is able to flag anomalies such as a message appearing out of its position in the normal sequence …