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- ANFIS (1)
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- Adaptive control (1)
- Artificial Neural Network (ANN) model (1)
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- Background model initialization and maintenance (1)
- Beam forming (1)
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- Cellular Neural Networks (1)
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- Distributed generation (1)
- Dominant colors (1)
- Earthquake forecast (1)
- Electric field measurement (1)
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- Fast Fourier Transform (FFT) (1)
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Articles 1 - 24 of 24
Full-Text Articles in Physical Sciences and Mathematics
A Robustness Analysis Procedure For Realistic Missiles, Reşat Özgür Doruk, Erol Kocaoğlan
A Robustness Analysis Procedure For Realistic Missiles, Reşat Özgür Doruk, Erol Kocaoğlan
Turkish Journal of Electrical Engineering and Computer Sciences
This paper presents a robustness analysis procedure for short range realistic missile autopilots. The sensitivity of the autopilots to the aerodynamic parameter uncertainties is investigated through the structured singular value theory where the results are verified through nonlinear simulations. Different types of perturbations are implemented in order to measure the complete performance of the missile.
Control Charts Approach For Scenario Recognition In Video Sequences, Ersi̇n Elbaşi, Long Zuo, Kishan Mehrotra, Chilukuri Mohan, Pramod Varshney
Control Charts Approach For Scenario Recognition In Video Sequences, Ersi̇n Elbaşi, Long Zuo, Kishan Mehrotra, Chilukuri Mohan, Pramod Varshney
Turkish Journal of Electrical Engineering and Computer Sciences
A new approach, based on control charts, is presented for the task of recognition of events and scenarios in video image sequences. For each image in the sequence, low level image processing and feature extraction steps result in feature descriptors for objects of interest detected in the images. Control charts analysis is then explored to classify the nature of the activity depicted by the temporal changes in these features over the image sequence. Scenario recognition with higher accuracy is achieved using this simple approach.
A New Cmos Differential Otra Design For The Low Voltage Power Supplies In The Sub-Micron Technologies, Alper Duruk, Hakan Kuntman
A New Cmos Differential Otra Design For The Low Voltage Power Supplies In The Sub-Micron Technologies, Alper Duruk, Hakan Kuntman
Turkish Journal of Electrical Engineering and Computer Sciences
In this study, a new CMOS differential OTRA topology is proposed. This topology can operate with a very low voltage power supply as \pm 0.6V. In this design, CMOS 0.13 \mu m STMicroelectronics technology transistor models are used for the simulations. The designed CMOS OTRA has a transresistance gain (Rm) of 7478 V/I with a 28.1 MHz bandwidth (-3 dB) and a transresistance unity-gain bandwidth of 2 GHz. To demonstrate the performance of the OTRA, designed low pass, high pass and band pass filters employing a single CMOS differential OTRA and passive elements are tested with SPICE simulation program to …
A Realization Of Sc-Cnn-Based Circuit Using Ftfn, Eni̇s Günay, Esma Uzunhi̇sarcikli, Recai̇ Kiliç, Mustafa Alçi
A Realization Of Sc-Cnn-Based Circuit Using Ftfn, Eni̇s Günay, Esma Uzunhi̇sarcikli, Recai̇ Kiliç, Mustafa Alçi
Turkish Journal of Electrical Engineering and Computer Sciences
In this paper, a realization of the State Controlled Cellular Neural Network (SC-CNN)-based circuit using Four Terminal Floating Nullor (FTFN) as active element is presented. In this realization, a new version of autonomous Chua's circuit has been considered using FTFN realization of SC-CNN-based circuit. The performance of the proposed SC-CNN-based circuit is demonstrated by PSpice simulations.
Sigma-Delta Voltage To Frequency Converter With Phase Modulation Possibility, Milan Stork
Sigma-Delta Voltage To Frequency Converter With Phase Modulation Possibility, Milan Stork
Turkish Journal of Electrical Engineering and Computer Sciences
Voltage to frequency converter (VFC) is an oscillator whose frequency is linearly proportional to control voltage. There are two common VFC architectures: the current steering multivibrator and the charge-balance VFC. For higher linearity, the charge-balancing method is preferred. The charge balanced VFC may be made in asynchronous or synchronous (clocked) forms. The synchronous charge balanced VFC or "sigma delta" (\Sigma-\Delta) VFC is used when output pulses are synchronized to a clock. The charge balance VFC is more complex, more demanding in its supply voltage and current requirements, and more accurate. It is capable of 16 to18 bit linearity. In this …
An Algorithm For Image Clustering And Compression, Meti̇n Kaya
An Algorithm For Image Clustering And Compression, Meti̇n Kaya
Turkish Journal of Electrical Engineering and Computer Sciences
This paper presents a new approach to image compression based on fuzzy clustering. This new approach includes pre-filtering, and fuzzy logic image enhancing to reduce undesirable noise effects on segmentation result; separation of image into 4x4 blocks and two dimensional discrete cosine transform; obtaining of peak values of cosine membership functions by combining of performing the zig-zag method with discrete cosine transform coefficients; obtaining of membership values and cluster centroids; and finally, creation of segmented image and compression. After applying the new method on sample images at different number of clusters, better compression ratio, performing time and good validity measure …
Impacts Of Distributed Generators On The Oscillatory Stability Of Interconnected Power Systems, İstemi̇han Genç, Ömer Usta
Impacts Of Distributed Generators On The Oscillatory Stability Of Interconnected Power Systems, İstemi̇han Genç, Ömer Usta
Turkish Journal of Electrical Engineering and Computer Sciences
Integration of distributed generation is continually and gradually affecting the stability of interconnected power systems. In this paper, the impacts of distributed synchronous generators on oscillatory stability are studied. In various parameter sub-spaces of interest, feasibility regions can be calculated to determine the conditions to sustain the stable operation of an interconnected power system. Through computations of the feasibility boundaries corresponding to Hopf bifurcations of electromechanical oscillatory modes, we determine the operating limits for a stable operation of the system under small and continual disturbances such as predictable changes in loading conditions of generators. Thus, with the case studies given …
Fault Tolerant Control With Re-Configuring Sliding-Mode Schemes, Ufuk Demi̇rci̇, Feza Kerestecioğlu
Fault Tolerant Control With Re-Configuring Sliding-Mode Schemes, Ufuk Demi̇rci̇, Feza Kerestecioğlu
Turkish Journal of Electrical Engineering and Computer Sciences
In this paper, a controller design method for linear MIMO systems is presented which a sliding mode controller is reconfigured in case of system faults. Faults are detected with the residual vector generated from a standard linear observer. Once a fault has been detected the fault distribution matrix can be obtained and used to update the corrective or equivalent control parts of the sliding mode controller. As a result, fault tolerant adaptive controllers keep the system performance within acceptable limits or at least avoids the system to wind-up.
Turbo Codes: The Issue Of Average Union Upper Bound Under Imperfect Channel State Information In Rayleigh Fading Channels, Erhan A. İnce, Syed Amjad Ali
Turbo Codes: The Issue Of Average Union Upper Bound Under Imperfect Channel State Information In Rayleigh Fading Channels, Erhan A. İnce, Syed Amjad Ali
Turkish Journal of Electrical Engineering and Computer Sciences
The potential of turbo codes to demonstrate excellent performance in the region of low signal to noise ratio is now a familiar fact. The idea of turbo codes was first introduced by Berrou and was based on the clever utilization of the existing decoding mechanism of BCJR with a change in the encoder by introducing feedback and an interleaver in the overall scheme. Since then, these powerful forward error correcting codes have attained a significant attention and have either replaced or have become a sturdy candidate for many applications in this era of modern communication systems. So far, a lot …
Silhouette Based Human Motion Detection And Analysis For Real-Time Automated Video Surveillance, Murat Eki̇nci̇, Eyüp Gedi̇kli̇
Silhouette Based Human Motion Detection And Analysis For Real-Time Automated Video Surveillance, Murat Eki̇nci̇, Eyüp Gedi̇kli̇
Turkish Journal of Electrical Engineering and Computer Sciences
In this paper, a real-time background modeling and maintenance based human motion detection and analysis in an indoor and an outdoor environments for visual surveillance system is described. The system operates on monocular gray scale video imagery from a static CCD camera. In order to detect foreground objects, first, background scene model is statistically learned using the redundancy of the pixel intensities in a training stage, even the background is not completely stationary. This redundancy information of the each pixel is separately stored in an history map shows how the pixel intensity values changes till now. Then the highest ratio …
Performance Analysis Of A Fuzzy Logic Based Rotor Resistance Estimator Of An Indirect Vector Controlled Induction Motor Drive, Y. Miloud, Azeddine Draou
Performance Analysis Of A Fuzzy Logic Based Rotor Resistance Estimator Of An Indirect Vector Controlled Induction Motor Drive, Y. Miloud, Azeddine Draou
Turkish Journal of Electrical Engineering and Computer Sciences
This paper presents a simple method for estimating rotor resistance in an indirect vector-controlled induction motor drive. This is important in vector control, if high-performance torque control is needed. For this purpose, a rotor resistance estimator using fuzzy logic technique is used and analysis, design, and digital simulations are carried out to demonstrate the effectiveness of the proposed estimator.
A Model For User Profiling Systems With Interacting Agents, Sanem Sariel, Tevfi̇k Akgün
A Model For User Profiling Systems With Interacting Agents, Sanem Sariel, Tevfi̇k Akgün
Turkish Journal of Electrical Engineering and Computer Sciences
Service systems according to users' personal demands and preferences are on their way to provide required services in many application domains. Emulation of interactive model of human societies produces valuable outcomes for such systems. In this work, a system model with interactive agents for multi user service systems is proposed. A novel social interactive agent model using different interaction forms is also included in this proposal. In this model, agents decide how to serve to their users by considering their users' profiles and information from other agents. User clusters are formed by clustering techniques. The Q-learning algorithm is used for …
Ultra Wide-Band : State Of The Art; Implementation Of A Performance-Controllable Low-Noise Amplifier, Serigne Dia, Balwant Godora, Frederic Alicalapa, Alain Fabre
Ultra Wide-Band : State Of The Art; Implementation Of A Performance-Controllable Low-Noise Amplifier, Serigne Dia, Balwant Godora, Frederic Alicalapa, Alain Fabre
Turkish Journal of Electrical Engineering and Computer Sciences
Ultra Wide-Band (UWB) transmissions exhibit performances vastly superior to existing wireless systems - superlative data-rate capacity, high security, low cost, low power consumption - and are emerging as the hottest topic of research for upcoming wireless generations. This communication protocol is studied in detail, with mention of the history and estimates for the near future; the present and possible applications are mentioned; the advantages and unresolved issues are detailed; a typical UWB transceiver architecture is studied; the modulation and coding schemes are enumerated; and the possibility of long-range communication is touched upon. Finally, a new performance-controllable low-noise amplifier (LNA) destined …
Prior Knowledge Input Method In Device Modeling, Serdar Heki̇mhan, Serdar Menekay, N. Serap Şengör
Prior Knowledge Input Method In Device Modeling, Serdar Heki̇mhan, Serdar Menekay, N. Serap Şengör
Turkish Journal of Electrical Engineering and Computer Sciences
The artificial neural networks are being used in modelling electronic elements and devices especially at microwave frequencies where non-linearity and dependence on frequency cannot be neglected. In this paper, instead of using artificial neural networks as a unique modelling device prior knowledge input method based on feed-forward artificial neural network structures as multi-layer perceptrons and wavelet-based neural networks is investigated. The benefits of prior knowledge input method over plain usage of artificial neural networks in modelling BJT is explored by comparing models obtained with and without prior knowledge input. The novelty of the paper is utilizing wavelet-based neural networks as …
Design, Simulation And Tests Of A Low-Cost Microstrip Patch Antenna Arrays For The Wireless Communication, Gonca Çakir, Levent Sevgi̇
Design, Simulation And Tests Of A Low-Cost Microstrip Patch Antenna Arrays For The Wireless Communication, Gonca Çakir, Levent Sevgi̇
Turkish Journal of Electrical Engineering and Computer Sciences
Typical low-cost, low-weight microstrip base station antenna arrays with beam-scanning capabilities are taken into account. In downtowns of large cities like New York, Chicago, and in historical cities like Istanbul, where high buildings are separated by narrow but densely occupied streets, antenna arrays with approximately 20°-35° beam-widths are required to complete the cellular communication coverage. To meet this requirement, new antenna arrays are designed with 35° beam-widths and 60° electronic scanning capabilities. Their characteristics are investigated both numerically and experimentally. An FDTD-based antenna simulation package (M-PATCH) is prepared, tested on canonical structures and against the literature first, for verification and …
Computation Of Association Probabilities For Single Target Tracking With The Use Of Adaptive Neuro-Fuzzy Inference System, İlke Türkmen, Keri̇m Güney
Computation Of Association Probabilities For Single Target Tracking With The Use Of Adaptive Neuro-Fuzzy Inference System, İlke Türkmen, Keri̇m Güney
Turkish Journal of Electrical Engineering and Computer Sciences
In this study, a simple method based on the adaptive neuro-fuzzy inference system (ANFIS) is presented for computing the association probabilities. The computed association probabilities are used to track the single manoeuvring target in the cluttered environment. A hybrid learning algorithm, which combines the least square method and the backpropagation algorithm, is used to identify the parameters of ANFIS. The tracks estimated by using the method proposed in this study are in very good agreement with the true tracks. Better accuracy with respect to the well known nearest neighbour Kalman filter and probabilistic data association algorithms is obtained.
Transformer Protection Using The Wavelet Transform, Okan Özgönenel, Güven Önbi̇lgi̇n, Çağri Kocaman
Transformer Protection Using The Wavelet Transform, Okan Özgönenel, Güven Önbi̇lgi̇n, Çağri Kocaman
Turkish Journal of Electrical Engineering and Computer Sciences
This paper introduces a novel approach for power transformer protection algorithm. Power system signals such as current and voltage have traditionally been analysed by the Fast Fourier Transform. This paper aims to prove that the Wavelet Transform is a reliable and computationally efficient tool for distinguishing between the inrush currents and fault currents. The simulated results presented clearly show that the proposed technique for power transformer protection facilitates the accurate discrimination between magnetizing inrush and fault currents in transformer protection.
Multilayer Capacitor Model Of The Earth's Upper Crust, Berk Üstündağ, Özcan Kalenderli̇, Haluk Eyi̇doğan
Multilayer Capacitor Model Of The Earth's Upper Crust, Berk Üstündağ, Özcan Kalenderli̇, Haluk Eyi̇doğan
Turkish Journal of Electrical Engineering and Computer Sciences
In this study, an equivalent electric circuit model of Earth's upper crust is proposed to explain the behavior of measurement patterns acquired from network of the earthquake forecast project. A multi-layer capacitor model having active components that couples with the monopolar probe close to the surface is used to determine earthquake precursory patterns due to structural changes in time. Equivalent circuit model was developed for a) dilatency process that is assumed to be a stress weakening reason and b) external force source that increases shear stress over the fault until sudden decrement before the earthquake. A data acquisition system consisting …
Two-Variable Scattering Formulas To Describe Some Classes Of Lossles Two-Ports With Mixed, Lumped Elements And Commensurate Stubs, Ahmet Sertbaş
Two-Variable Scattering Formulas To Describe Some Classes Of Lossles Two-Ports With Mixed, Lumped Elements And Commensurate Stubs, Ahmet Sertbaş
Turkish Journal of Electrical Engineering and Computer Sciences
Using the semi-analytic method based on the construction of two-variable scattering functions, which describe lossless two-ports with two kinds of elements, for some classes of ladder networks formed with lumped elements and commensurate stubs, the explicit descriptive formulas are produced up to six mixed-elements. To exhibit the efficiency of the explicit descriptive equations in the design of the broadband microwave circuits, a single matching design problem (UHF antenna matching) is solved by using the obtained two-variable scattering formulas.
A Survey On The H.264/Avc Standard, Nükhet Özbek, Turhan Tunali
A Survey On The H.264/Avc Standard, Nükhet Özbek, Turhan Tunali
Turkish Journal of Electrical Engineering and Computer Sciences
H.264/AVC is a recently completed video compression standard jointly developed by ITU-T VCEG and ISO/IEC MPEG standards committees. The standard is becoming more popular as it promises much higher compression than that possible with earlier standards. The standard provides flexibilities in coding and organization of data which enable efficient error resilience. The increased coding efficiency offers new application areas and business opportunities. As might be expected, the increases in compression efficiency and flexibility come at the expense of increase in complexity, which is a fact that must be overcome. This paper provides an overview of the technical features of H.264 …
Color Image Profiling Using Fuzzy Sets, Amine Ait Younes, Isis Truck, Herman Akdag
Color Image Profiling Using Fuzzy Sets, Amine Ait Younes, Isis Truck, Herman Akdag
Turkish Journal of Electrical Engineering and Computer Sciences
In this article, a software for image indexing and retrieval is presented. The classification proposed here is based on the dominant color(s) of the images. The process consists in assigning a colorimetric profile to the image in HLS space (Hue, Lightness, Saturation). First, the definition of hue is done thanks to a fuzzy representation to take into account the non-uniformity of colors distribution. And then, lightness and saturation are represented through linguistic qualifiers also defined in a fuzzy way. Finally, the profile is built through fuzzy functions representing the membership degree of the image to different classes. In order to …
Implementation Of A New Self-Tuning Fuzzy Pid Controller On Plc, Onur Karasakal, Engi̇n Yeşi̇l, Müjde Güzelkaya, İbrahi̇m Eksi̇n
Implementation Of A New Self-Tuning Fuzzy Pid Controller On Plc, Onur Karasakal, Engi̇n Yeşi̇l, Müjde Güzelkaya, İbrahi̇m Eksi̇n
Turkish Journal of Electrical Engineering and Computer Sciences
In this study, the self-tuning method for fuzzy PID controllers that has been developed in a previous study of the authors is implemented on PLC in order to control some standard processes formed on FEEDBACK PCS 327 Process Control Simulator. In this tuning method, the input scaling factor corresponding to the derivative coefficient and the output scaling factor corresponding to the integral coefficient of the fuzzy PID controller are adjusted using a fuzzy inference mechanism with a new input called ``normalized acceleration''. The results of the implementation have been compared with those of the classical fuzzy PID controller without a …
Soft Computing Methods In Microwave Active Device Modeling, Yavuz Cengi̇z, Fi̇li̇z Güneş, Mehmet Fati̇h Çağlar
Soft Computing Methods In Microwave Active Device Modeling, Yavuz Cengi̇z, Fi̇li̇z Güneş, Mehmet Fati̇h Çağlar
Turkish Journal of Electrical Engineering and Computer Sciences
In this work, the signal and noise behaviors of a microwave transistor within its operation domain (CT,V_{DS}, I_{DS}, f) are modeled by the Artificial Neural Network (ANN) and Fuzzy Logic System (FLS) without using any information on the microwave circuit theory . A worked example is presented where the same data is employed for both models selected from the manufacturer's data sheets. Performances of the FLS and ANN models are compared and conclusions are drawn.
A Content-Based Fuzzy Image Database Based On The Fuzzy Artmap Architecture, M. Uysal, Fatoş Tünay Yarman Vural
A Content-Based Fuzzy Image Database Based On The Fuzzy Artmap Architecture, M. Uysal, Fatoş Tünay Yarman Vural
Turkish Journal of Electrical Engineering and Computer Sciences
A major design issue in content-based image retrieval system is the selection of the feature set. This study attacks the problem of finding a discriminative feature for each class, which is optimal in some sense. Fuzzy ARTMAP architecture is used to find this discriminative feature set. For this purpose, initially, a large variety of features are extracted from the regions of the pre-segmented images. Then, the feature set of each object class is learned using the Fuzzy Art Map Architecture, by identifying the weights of each feature for each object class. In the querying phase, trained set of feature weights …