Open Access. Powered by Scholars. Published by Universities.®
Physical Sciences and Mathematics Commons™
Open Access. Powered by Scholars. Published by Universities.®
- Keyword
-
- HF radar (4)
- HFSWR (3)
- Adaptive control (2)
- Artificial neural network (2)
- Chaos (2)
-
- High Frequency Surface Wave Radar (2)
- Induction machine (2)
- Nonlinear systems (2)
- OTH radar (2)
- Particle swarm optimization (2)
- Privacy (2)
- RCS (2)
- Radar (2)
- State estimation (2)
- Tracking (2)
- AIA (1)
- ANFIS (1)
- AR model (1)
- Accuracy enhancement (1)
- Accuracy. (1)
- Active appearance (1)
- Actuator design (1)
- Adaptive neuro-fuzzy inference system (1)
- Adaptive systems (1)
- Alignment (1)
- All-pass filter (1)
- Analyzer; data acquisition; harmonics; microcontroller; PQ monitoring; MSP; power quality. (1)
- Anonymity; Wireless Sensor Networks; Data Privacy. (1)
- Ant colony optimization (1)
- Autonomous (1)
Articles 1 - 30 of 75
Full-Text Articles in Physical Sciences and Mathematics
Remote Sensing Applications Of Hf Skywave Radar: The Australian Experience, Stuart Anderson
Remote Sensing Applications Of Hf Skywave Radar: The Australian Experience, Stuart Anderson
Turkish Journal of Electrical Engineering and Computer Sciences
Australia has conducted research into over-the-horizon radar (OTHR) for almost sixty years. Early programs focused exclusively on military capabilities, such as the detection of aircraft, missiles and ships, but in 1974 a team was formed to design a new OTHR for which a remote sensing mission was proposed. Oceanic wind mapping experiments in 1977-78 yielded promising results so remote sensing became a recognised mission assigned to the new radar, known as Jindalee Stage B. This capability was progressively expanded over the period 1982-87 to include mapping of wave height and other oceanographic variables. A real-time data link to the Australian …
Improved Analytical Modulation Transfer Function For Image Intensified Charge Coupled Devices*, Nebi̇ Gül, Murat Efe
Improved Analytical Modulation Transfer Function For Image Intensified Charge Coupled Devices*, Nebi̇ Gül, Murat Efe
Turkish Journal of Electrical Engineering and Computer Sciences
The basic problem of simulation and modeling of Image Intensified Charge Coupled Device (ICCD) is the difference between the analytical Modulation Transfer Function (MTF) formulation used in the model and the experimentally obtained MTF. An investigation into the MTF of ICCD sub-components reveal that the MTF of the Image Intensifier Tube (IIT) is the main factor in this deviation. In this study, a regulation factor for the MTF of 3^{rd} generation IITs has been developed. A commonly used MTF formulation for IITs has been modified to include a regulation factor which has helped produce more precise MTF values for the …
P2p Collaborative Filtering With Privacy, Ci̇han Kaleli̇, Hüseyi̇n Polat
P2p Collaborative Filtering With Privacy, Ci̇han Kaleli̇, Hüseyi̇n Polat
Turkish Journal of Electrical Engineering and Computer Sciences
With the evolution of the Internet and e-commerce, collaborative filtering (CF) and privacy-preserving collaborative filtering (PPCF) have become popular. The goal in CF is to generate predictions with decent accuracy, efficiently. The main issue in PPCF, however, is achieving such a goal while preserving users' privacy. Many implementations of CF and PPCF techniques proposed so far are centralized. In centralized systems, data is collected and stored by a central server for CF purposes. Centralized storage poses several hazards to users because the central server controls users' data. In this work, we investigate how to produce naïve Bayesian classifier (NBC)-based recommendations …
Dual-Use Of Compact Hf Radars For The Detection Of Mid- And Large-Size Vessels, Hugh Roarty, Don Barrick, Josh Kohut, Scott Glenn
Dual-Use Of Compact Hf Radars For The Detection Of Mid- And Large-Size Vessels, Hugh Roarty, Don Barrick, Josh Kohut, Scott Glenn
Turkish Journal of Electrical Engineering and Computer Sciences
This paper describes the development of the SeaSonde High Frequency Radar system into a dual-use application for the mapping of ocean surface currents and detection of ships at sea. This development entailed the creation of a new radar waveform that would permit this dual-use as well as a detection algorithm to identify the ships in the radar spectra. The detection algorithm utilizes two methods for calculating a background signal level: an infinite impulse response (IIR) filter and a two-dimensional median filter. These two methods are employed simultaneously with multiple length averaging times to maximize the number of detections. The initial …
Antenna Systems With Beam Forming And Beam Steering Capabilities For Hf Skywave Radars, Çağatay Uluişik
Antenna Systems With Beam Forming And Beam Steering Capabilities For Hf Skywave Radars, Çağatay Uluişik
Turkish Journal of Electrical Engineering and Computer Sciences
Radiation characteristics of linearly phased, periodic, planar dipole arrays, which can be used as transmitting/receiving antenna systems for HF skywave radars, are investigated. Rectangular, triangular and trapezoidal arrays are proposed in obtaining different beam shapes in the desired directions. Beam steering is achieved by adjusting the inter-element phase increments coherently. The effects of vertical array-tilt with a desired take-off angle (TOA) \alpha are presented by a number of radiation pattern examples. The ground effect is investigated using the image theory by assuming the Earth's surface as perfectly electric conductor (PEC). Radiated fields are obtained using Floquet wave representations plus the …
Hierarchical Fuzzy Controller Applied To Multi-Input Power System Stabilizer, Ebrahim Rasooli Anarmarzi, Mohammad Reza Feyzi, Mehrdad Tarafdar Hagh
Hierarchical Fuzzy Controller Applied To Multi-Input Power System Stabilizer, Ebrahim Rasooli Anarmarzi, Mohammad Reza Feyzi, Mehrdad Tarafdar Hagh
Turkish Journal of Electrical Engineering and Computer Sciences
This paper proposes the application of a hierarchical fuzzy system (HFS) based on multi-input power system stabilizer (MPSS) in multi-machine environment. The number of rules increases exponentially with the number of variables in a standard fuzzy system. This problem is solved in the proposed HFS method. In this method, the total number of rules increases only linearly with the number of input variables. HFS consists of a number of low-dimensional fuzzy systems in a hierarchical form. In the MPSS, the deviation of reactive power \Delta Q is added to a \Delta P+ \Delta \omega input type Power System Stabilizer (PSS) …
Washout Filter Based Control For The Hodgkin-Huxley Nerve Cell Dynamics, Reşat Özgür Doruk
Washout Filter Based Control For The Hodgkin-Huxley Nerve Cell Dynamics, Reşat Özgür Doruk
Turkish Journal of Electrical Engineering and Computer Sciences
In this work we present a washout filter based control approach for stabilizing the oscillations in Hodgkin-Huxley type neurons. The oscillations occur due to the bifurcations that arise from the potassium and sodium channel conductance deviations. The MATCONT toolbox software environment was used for analysis of the bifurcation points in conjunction with MATLAB. The simulations of the Hodgkin-Huxley (HH) model at those points are provided to validate the results obtained from the MATCONT software. Then a washout filter is proposed to stabilize the oscillations occur at the Hopf bifurcation points where the external current injection is used to provide the …
Active Illumination And Appearance Model For Face Alignment, Muhi̇tti̇n Gökmen, Fati̇h Kahraman, Sune Darkner, Rasmus Larsen
Active Illumination And Appearance Model For Face Alignment, Muhi̇tti̇n Gökmen, Fati̇h Kahraman, Sune Darkner, Rasmus Larsen
Turkish Journal of Electrical Engineering and Computer Sciences
Illumination conditions have an explicit effect on the performance of face recognition systems. In particular, varying the illumination upon the face imposes such complex effects that the identification often fails to provide a stable performance level. In this paper, we propose an approach integrating face identity and illumination models in order to reach acceptable and stable face recognition rates. For this purpose, Active Appearance Model (AAM) and illumination model of faces are combined in order to obtain an illumination invariant face localization. The proposed method is an integrated Active Illumination and Appearance Model (AIA) which combines identity, illumination and shape …
Sdre Optimal Control Of Drug Administration In Cancer Treatment, Mehmet İti̇k, Meti̇n Uymaz Salamci̇, Stephen Paul Banks
Sdre Optimal Control Of Drug Administration In Cancer Treatment, Mehmet İti̇k, Meti̇n Uymaz Salamci̇, Stephen Paul Banks
Turkish Journal of Electrical Engineering and Computer Sciences
In this study, we apply State Dependent Riccati Equation (SDRE) based optimal control technique to a nonlinear tumor growth model. The model consists of three biological cells which are normal tissue, tumor and immune cells. The effect of chemotherapy treatment is also included in the model. Chemotherapy administration is considered as a control input to the nonlinear cancer dynamics and the amount of administered drug is determined by using SDRE optimal control. The optimal control is applied to the model in order not only to drive the tumor cells to the healthy equilibrium state but also to minimize the amount …
Analysis And Estimation Of Motion Transmission Errors Of A Timing Belt Drive, Ergi̇n Kiliç, Meli̇k Dölen, Ahmet Buğra Koku
Analysis And Estimation Of Motion Transmission Errors Of A Timing Belt Drive, Ergi̇n Kiliç, Meli̇k Dölen, Ahmet Buğra Koku
Turkish Journal of Electrical Engineering and Computer Sciences
This paper focuses on viable position estimation schemes for timing belt drives where the position of the carriage (load) is to be determined via reference models receiving input from a position sensor attached to the actuator of the timing belt. A detailed analysis of the transmission error sources is presented, and a number of relevant mathematical models are developed using a priori knowledge of the process. This paper demonstrates that such schemes are very effective when the drive system is not subjected to external loads and operating conditions do not change considerably i.e. ambient temperature, belt tension.
Optimal Feature Selection For 3d Facial Expression Recognition Using Coarse-To-Fine Classification, Hamit Soyel, Hasan Demirel
Optimal Feature Selection For 3d Facial Expression Recognition Using Coarse-To-Fine Classification, Hamit Soyel, Hasan Demirel
Turkish Journal of Electrical Engineering and Computer Sciences
Automatic facial expression recognition for novel individuals from 3D face data is a challenging task in pattern analysis. This paper describes a feature selection process for pose-invariant 3D facial expression recognition. The process provides a lower dimensional subspace representation, which is optimized to improve the classification accuracy, retrieved from geometrical localization of facial feature points to classify facial expressions. Fisher criterion-based approach is adopted to provide a basis for the optimal selection of features. Two-stage probabilistic neural network architecture is employed as a classifier to recognize the facial expressions. In the first stage, which can be regarded as the coarse …
A Second Order Approximation To Reduce The Complexity Of Ldpc Decoders Based On Gallager's Approach, Aykut Kalaycioğlu, Oktay Üreten, H. Gökhan İlk
A Second Order Approximation To Reduce The Complexity Of Ldpc Decoders Based On Gallager's Approach, Aykut Kalaycioğlu, Oktay Üreten, H. Gökhan İlk
Turkish Journal of Electrical Engineering and Computer Sciences
A piece-wise second order approximation to the f (x) = -log [tanh (x/2)] function is proposed to reduce the computational complexity of LDPC decoder's utilizing Log-Likelihood Ratio Belief Propagation (LLR-BP) algorithm based on Gallager's approach. Simulation results show that the proposed low complexity approximation doesn't cause BER performance degradation.
Adaptive Neuro-Fuzzy Inference System To Improve The Power Quality Of Variable-Speed Wind Power Generation System, Yüksel Oğuz, Kami̇l Ri̇fat İrfan Güney
Adaptive Neuro-Fuzzy Inference System To Improve The Power Quality Of Variable-Speed Wind Power Generation System, Yüksel Oğuz, Kami̇l Ri̇fat İrfan Güney
Turkish Journal of Electrical Engineering and Computer Sciences
In this study, an adaptive neuro-fuzzy inference system is designed for output voltage and frequency control of a variable-speed wind power generation system. Variable-speed wind power generation systems (VSWPGS) provide the opportunity to capture more power than fixed speed turbines. On the other hand, the variable-speed wind turbine output can be variable voltage and variable frequency for fluctuating wind speeds. The quality of output power can be improved if adequate controls are incorporated in the system. To bring the output voltage and frequency of system by means of control of blade pitch angle of wind turbine to a desirable value, …
A New Chaotic Attractor From General Lorenz System Family And Its Electronic Experimental Implementation, İhsan Pehli̇van, Yilmaz Uyaroğlu
A New Chaotic Attractor From General Lorenz System Family And Its Electronic Experimental Implementation, İhsan Pehli̇van, Yilmaz Uyaroğlu
Turkish Journal of Electrical Engineering and Computer Sciences
This article introduces a novel three-dimensional continuous autonomous chaotic system with six terms and two quadratic nonlinearities. The new system contains two variational parameters and exhibits Lorenz-like attractors in numerical simulations and experimental measurements. The basic dynamical properties of the new system are analyzed by means of equilibrium points, eigenvalue structures, and Lyapunov exponents. The new system examined in Matlab-Simulink^{\textregistered} and Orcad-PSpice^{\textregistered}. An electronic circuit realization of the proposed system is presented using analog electronic elements such as capacitors, resistors, operational amplifiers and multipliers. The behaviour of the realized system is evaluated with computer simulations.
Oceanography Radar System Wera: Features, Accuracy, Reliability And Limitations, Thomas Helzel, Matthias Kniephoff, Leif Petersen
Oceanography Radar System Wera: Features, Accuracy, Reliability And Limitations, Thomas Helzel, Matthias Kniephoff, Leif Petersen
Turkish Journal of Electrical Engineering and Computer Sciences
The WERA system (WavE RAdar) is a shore based remote sensing system to monitor ocean surface currents, waves and wind direction. This long range, high resolution monitoring system based on short radio wave radar technology. The vertical polarised electromagnetic wave is coupled to the conductive ocean surface and follows the curvature of the earth. This over the horizon oceanography radar can pick up back-scattered signals from the rough ocean surface (Bragg effect) from ranges of up to 200 km. The physical background, technical concept and environmental boundary conditions are explained. Results for various installations from all over the world demonstrates …
Corrective Action Planning Considering Facts Allocation And Optimal Load Shedding Using Bacterial Foraging Oriented By Particle Swarm Optimization Algorithm, Rahmat Allah Hooshmand, Mostafa Ezatabadi
Corrective Action Planning Considering Facts Allocation And Optimal Load Shedding Using Bacterial Foraging Oriented By Particle Swarm Optimization Algorithm, Rahmat Allah Hooshmand, Mostafa Ezatabadi
Turkish Journal of Electrical Engineering and Computer Sciences
Reactive power planning (RPP) involves optimal allocation and determination of the type and size of new reactive power (VAR) supplies to satisfy voltage constraints during normal and contingency states. The RPP issue is in fact an optimization of large scale mixed integer nonlinear programming problem, so it is proper to use an evolutionary algorithm to solve the problem. In this paper, in order to solve the RPP problem for corrective action of power systems, the bacterial foraging (BF) oriented by particle swarm optimization (PSO) algorithm (BF-PSO) is proposed. In the algorithm, the VAR control has been carried out by using …
Formation Control Of Nonholonomic Mobile Robots Using Implicit Polynomials And Elliptic Fourier Descriptors, Yeşi̇m Hümay Esi̇n, Mustafa Ünel
Formation Control Of Nonholonomic Mobile Robots Using Implicit Polynomials And Elliptic Fourier Descriptors, Yeşi̇m Hümay Esi̇n, Mustafa Ünel
Turkish Journal of Electrical Engineering and Computer Sciences
This paper presents a novel method for the formation control of a group of nonholonomic mobile robots using implicit and parametric descriptions of the desired formation shape. The formation control strategy employs implicit polynomial (IP) representations to generate potential fields for achieving the desired formation and the elliptical Fourier descriptors (EFD) to maintain the formation once achieved. Coordination of the robots is modeled by linear springs between each robot and its two nearest neighbors. Advantages of this new method are increased flexibility in the formation shape, scalability to different swarm sizes and easy implementation. The shape formation control is first …
Precise Position Control Using Shape Memory Alloy Wires, Burcu Dönmez, Bülent Özkan, Fevzi̇ Suat Kadioğlu
Precise Position Control Using Shape Memory Alloy Wires, Burcu Dönmez, Bülent Özkan, Fevzi̇ Suat Kadioğlu
Turkish Journal of Electrical Engineering and Computer Sciences
Shape memory alloys (SMAs) are active metallic ``smart'' materials used as actuators and sensors in high technology smart systems [1]. The term shape memory refers to ability of certain materials to ``remember'' a shape, even after rather severe deformations: once deformed at low temperatures, these materials will stay deformed until heated, whereupon they will return to their original, pre-deformed ``learned'' shape [2]. This property can be used to generate motion and/or force in electromechanical devices and micro-machines. However, the accuracy of SMA actuators is severely limited by their highly nonlinear stimulus-response characteristics. In this work, modeling, simulation, and experimental efforts …
Design Of Optimal Sampling Times For Pharmacokinetic Trials Via Spline Approximation, Musa Hakan Asyali
Design Of Optimal Sampling Times For Pharmacokinetic Trials Via Spline Approximation, Musa Hakan Asyali
Turkish Journal of Electrical Engineering and Computer Sciences
Understanding and comparison of different drug delivery formulations are based on pharmacokinetic parameters (PKP) such as area under curve, maximum concentration, and time to reach maximum concentration. Accurate estimation of PKP is of critical importance in capturing drug absorption and elimination characteristics and in reaching bioequivalence decisions. Since PKP are estimated from a limited number of samples, the timing of the samples directly influences the accuracy of estimation. Optimization of the sampling times may not only increase the accuracy of PKP estimation, but also reduce the number of samples to be drawn, which in turn lessens the inconvenience to the …
Artificial Neural Network Based Chaotic Generator For Cryptology, İlker Dalkiran, Kenan Danişman
Artificial Neural Network Based Chaotic Generator For Cryptology, İlker Dalkiran, Kenan Danişman
Turkish Journal of Electrical Engineering and Computer Sciences
Chaotic systems are sensitive to initial conditions, system parameters and topological transitivity and these properties are also remarkable for cryptanalysts. Noise like behavior of chaotic systems is the main reason of using these systems in cryptology. However some properties of chaotic systems such as synchronization, fewness of parameters etc. cause serious problems for cryptology. In this paper, to overcome disadvantages of chaotic systems, the dynamics of Chua's circuit namely x, y and z were modeled using Artificial Neural Network (ANN). ANNs have some distinctive capabilities like learning from experiences, generalizing from a few data and nonlinear relationship between inputs and …
Radar Cross-Section (Rcs) Analysis Of High Frequency Surface Wave Radar Targets, Gonca Çakir, Levent Sevgi̇
Radar Cross-Section (Rcs) Analysis Of High Frequency Surface Wave Radar Targets, Gonca Çakir, Levent Sevgi̇
Turkish Journal of Electrical Engineering and Computer Sciences
Realistic high frequency surface wave radar (HFSWR) targets are investigated numerically in terms of electromagnetic wave -- target interactions. Radar cross sections (RCS) of these targets are simulated via both the finite-difference time-domain (FDTD) method and the Method of Moments (MoM). The virtual RCS prediction tool that was introduced in previous work is used for these investigations. The virtual tool automatically creates the discrete FDTD model of the target under investigation and performs the FDTD RCS analysis. It also automatically constructs a MoM wire grid model of the target; therefore, it is also possible to compare FDTD results against the …
Direct Discrete-Time Control Of Port Controlled Hamiltonian Systems, Yaprak Yalçin, Leyla Gören Sümer
Direct Discrete-Time Control Of Port Controlled Hamiltonian Systems, Yaprak Yalçin, Leyla Gören Sümer
Turkish Journal of Electrical Engineering and Computer Sciences
The direct discrete time control of Port Controlled Hamiltonian Systems (PCHS) in the sense of energy shaping and damping injection is considered. In order to give a direct discrete time design method for PCHS, firstly an appropriate discrete gradient is proposed, which enables the derivation of a discrete time equation corresponding to the discrete time counterpart of Hamiltonian Systems. Using this proposed discrete-time model, the discrete-time counterpart of Passivity Based Control (PBC) technique is developed for n-degrees-of-freedom mechanical systems. The discrete-time control rules which correspond to the energy shaping and damping assignment are obtained directly using the discrete time model …
State Variable Distributed-Parameter Representation Of Transmission Line For Transient Simulations, Mehmet Sali̇h Mami̇ş, Asim Kaygusuz, Muhammet Köksal
State Variable Distributed-Parameter Representation Of Transmission Line For Transient Simulations, Mehmet Sali̇h Mami̇ş, Asim Kaygusuz, Muhammet Köksal
Turkish Journal of Electrical Engineering and Computer Sciences
In this paper, a distributed-parameter state variable approach is used to calculate transients on transmission lines based on the concept of travelling waves. The method of characteristics for lossless line is used and the state equations are derived for the system. These equations are converted to a set of difference equations using the trapezoidal rule of integration and solved in time domain using LU decomposition. Single- and multi-phase transmission lines with various linear and non-linear terminations are considered in the illustrative examples. State-space modeling of transposed lines using modal decomposition is introduced and the effects caused by lumped parameter approximation …
Adaptive Hysteresis Band Control For Constant Switching Frequency In Dtc Induction Machine Drives, H. İbrahi̇m Okumuş, Mustafa Aktaş
Adaptive Hysteresis Band Control For Constant Switching Frequency In Dtc Induction Machine Drives, H. İbrahi̇m Okumuş, Mustafa Aktaş
Turkish Journal of Electrical Engineering and Computer Sciences
It is fairly well known that direct torque control (DTC) exhibits fast dynamic torque response, a property that originates in the fact that torque and flux is directly controlled by instantaneous space voltage vector, unlike field-oriented control. For this reason direct torque control gradually has been used in the field, eliciting quick response and high efficiency since its introduction in the mid-1980s. Conventional fixed band hysteresis control has several problems. One of these is variable switching frequency, which causes serious problems in DTC. In this paper, an adaptive hysteresis band control strategy is proposed, where the hysteresis band is controlled …
Comparison Of Daubechies Wavelets For Hurst Parameter Estimation, Cebrai̇l Çi̇ftli̇kli̇, Ali̇ Gezer
Comparison Of Daubechies Wavelets For Hurst Parameter Estimation, Cebrai̇l Çi̇ftli̇kli̇, Ali̇ Gezer
Turkish Journal of Electrical Engineering and Computer Sciences
Time scale dependence on the working nature of wavelet analysis makes it a valuable tool for Hurst parameter estimation. Similar to other wavelet-based signal processing applications, the selection of a particular wavelet type and vanishing moment in wavelet based Hurst estimation is a challenging problem. In this paper, we investigate the best Daubechies wavelet in wavelet based Hurst estimation for an exact self similar process, fractional Gaussian noise and how Daubechies vanishing moment affects the Hurst estimation accuracy. Daubechies wavelets are preferred in analysis because increasing vanishing moment does not cause excessive increase of time support of Daubechies wavelets. Thus, …
Experimental Studies Of A Scaled-Down Tsr-Based Svc And Tcr-Based Svc Prototype For Voltage Regulation And Compensation, Ayetül Gelen, Tankut Yalçinöz
Experimental Studies Of A Scaled-Down Tsr-Based Svc And Tcr-Based Svc Prototype For Voltage Regulation And Compensation, Ayetül Gelen, Tankut Yalçinöz
Turkish Journal of Electrical Engineering and Computer Sciences
In this paper, prototypes of two shunt flexible AC transmission system (FACTS) devices, a thyristor switched reactor (TSR)-based static VAr compensator (SVC) and a thyristor controlled reactor (TCR)-based static VAr compensator- have been developed. The design and testing of both a TSR-based SVC and a TCR-based SVC are accomplished in the Power Systems Research Laboratory of Nigde University. The TSR-based SVC and TCR-based SVC devices are studied in three-bus and single machine infinite bus systems for three-phase static load conditions. The effects of TSR-based SVC and TCR-based SVC devices on load voltages are also analyzed. Experimental results show that significant …
Robust Multimedia Watermarking: Hidden Markov Model Approach For Video Sequences, Ersi̇n Elbaşi
Robust Multimedia Watermarking: Hidden Markov Model Approach For Video Sequences, Ersi̇n Elbaşi
Turkish Journal of Electrical Engineering and Computer Sciences
Because of the large amount of frames, similarity between frames and temporal attacks (frame dropping, frame averaging, frame swapping etc.), the process for video watermarking is more difficult than that for image watermarking. Current image watermarking methods are limited to solve all these difficulties. We propose a novel video watermarking system based on the Hidden Markov Model (HMM). This novel watermarking scheme splits the video sequences into a Group of Pictures (GOP) with HMM. Portions of the binary watermark are embedded into each GOP with a wavelet domain watermarking algorithm. The embedding process is the standard additive algorithm [1] in …
The Effect Of Heat On The Metallurgical Structure And B-H Characteristic Of (Stator) Armature With Iron-Silicon Alloy In Electric Machines, Fevzi̇ Kentli̇, Ümi̇t Kemaletti̇n Terzi̇
The Effect Of Heat On The Metallurgical Structure And B-H Characteristic Of (Stator) Armature With Iron-Silicon Alloy In Electric Machines, Fevzi̇ Kentli̇, Ümi̇t Kemaletti̇n Terzi̇
Turkish Journal of Electrical Engineering and Computer Sciences
Coils in electric machines are varnished for insulation after winding. These varnished coils are formed in stiff construction in slots. Under heavy-duty operating conditions, all or part of some coils may be burnt or broken. Thermal method is one of several ways to remove the defective coils. In this method, current is passed through the defective coils by an autotransformer (variac) until all the varnish of the coils is burned. If all the coils are out of order, the varnish is burned by replacing the stator or armature in a burning room. Consequently, defective coils in the stator (armature) slots …
Implementation Of Method For Operating Multiple High Frequency Surface Wave Radars On A Common Carrier Frequency, Ryan Riddolls
Implementation Of Method For Operating Multiple High Frequency Surface Wave Radars On A Common Carrier Frequency, Ryan Riddolls
Turkish Journal of Electrical Engineering and Computer Sciences
The increasing use of High Frequency Surface Wave Radar (HFSWR) for the surveillance of coastal regions is faced with the problem of limited channel availability in the electromagnetic spectrum. Thus, there is a need for multiple radars to share a common frequency channel. Proof-of-concept work is presented here for a method to operate multiple radar systems on a common carrier frequency. A review is provided of an existing concept where a common waveform is modulated by tones varying by a few hertz across the different radars. The signals from the different radars are separated by either pulse-domain filtering or Doppler …
A New Multi-Tier Adaptive Military Manet Security Protocol Using Hybrid Cryptography And Signcryption, Atti̇la A. Yavuz, Fati̇h Alagöz, Emi̇n Anarim
A New Multi-Tier Adaptive Military Manet Security Protocol Using Hybrid Cryptography And Signcryption, Atti̇la A. Yavuz, Fati̇h Alagöz, Emi̇n Anarim
Turkish Journal of Electrical Engineering and Computer Sciences
Mobile Ad-hoc NETworks (MANETs) are expected to play an important role in tactical military networks by providing infrastructureless communication. However, maintaining secure and instant information sharing is a difficult task especially for highly dynamic military MANETs. To address this requirement, we propose a new multi-tier adaptive military MANET security protocol using hybrid cryptography and signcryption. In our protocol, we bring novelties to secure military MANET communication for three main points: Cryptographic methods used in MANETs, hybrid key management protocols and structural organization of the military MANETs. As a new approach, we use hybrid cryptography mechanisms and Elliptic Curve Pintsov-Vanstone Signature …