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Full-Text Articles in Physical Sciences and Mathematics

Experimental Analysis Of The Temperature Dependence Of The Brillouin Gain Spectrum In Short-Length Single-Mode Fiber, Murat Yücel, Hali̇m Haldun Göktaş, Murat Yücel, Nai̇l Ferhat Öztürk, Abdullah Erkam Gündüz Jan 2017

Experimental Analysis Of The Temperature Dependence Of The Brillouin Gain Spectrum In Short-Length Single-Mode Fiber, Murat Yücel, Hali̇m Haldun Göktaş, Murat Yücel, Nai̇l Ferhat Öztürk, Abdullah Erkam Gündüz

Turkish Journal of Electrical Engineering and Computer Sciences

The Brillouin backscattered wave was examined in a short-length single-mode fiber at different ambient temperatures using a 1553-nm wavelength laser source. To obtain Brillouin scattering depending on the temperature change in a 95-m long single-mode fiber cable, the Brillouin optical time domain reflectometry (BOTDR) technique was used. In this technique, a 1553 nm wavelength signal was sent from one side of the test fiber. The FC/APC connector was attached to the other end of the test fiber. The temperature parameters of the single-mode fiber cables of different brands and types can be obtained using Brillouin scattering. The Brillouin frequency shift …


Concurrent Optimal Design Of Tcsc And Pss Using Symbiotic Organisms Search Algorithm, Muwaffaq Alomoush Jan 2017

Concurrent Optimal Design Of Tcsc And Pss Using Symbiotic Organisms Search Algorithm, Muwaffaq Alomoush

Turkish Journal of Electrical Engineering and Computer Sciences

The symbiotic organisms search (SOS), which has been recently introduced, is a robust powerful metaheuristic global optimizer. This nature-inspired algorithm imitates the symbiotic interaction strategies in an ecosystem exercised by organisms involved in interrelationships to survive and reproduce. One of the main beneficial features of the SOS in contrast to many other competent metaheuristic algorithms is that the algorithm does not need any specific algorithm parameters or tuning process. This paper applies the SOS algorithm to simultaneously design optimal controllers of a power system equipped with both a power system stabilizer (PSS) and a thyristor-controlled series compensator (TCSC). The algorithm …


Inverse Kinematics Of A 7-Dof Redundant Robot Manipulator Using The Active Set Approach Under Joint Physical Limits, Modjtaba Rouhani, Sima Ebrahimabadi Jan 2017

Inverse Kinematics Of A 7-Dof Redundant Robot Manipulator Using The Active Set Approach Under Joint Physical Limits, Modjtaba Rouhani, Sima Ebrahimabadi

Turkish Journal of Electrical Engineering and Computer Sciences

This paper presents a new approach for an online solution of the inverse kinematics problem based on nonlinear optimization for robots with joint physical constraints. The inverse kinematics problem is stated as a constrained nonlinear optimization problem and is solved using Kuhn--Tucker conditions analysis. The nonlinear multivariable optimization problem is locally converted into independent local linear constrained subproblems and each subproblem is analytically solved. For each joint, position limits and velocity limits are considered as physical constraints. The proposed structure benefits from a very low complexity design. The proposed method is fast and requires few calculations. The convergence of the …


A Model Of Optimal Burst Assembly For Delay Reduction At Ingress Obs Nodes, Viet Minh Nhat Vo, Van Hoa Le, Hoang Son Nguyen Jan 2017

A Model Of Optimal Burst Assembly For Delay Reduction At Ingress Obs Nodes, Viet Minh Nhat Vo, Van Hoa Le, Hoang Son Nguyen

Turkish Journal of Electrical Engineering and Computer Sciences

Burst assembly plays an important role in reducing the end-to-end delay of packets transported through optical burst switching (OBS) networks. Several methods have been proposed to reduce the delay of the packets buffered at ingress OBS nodes. However, these have created significant estimation errors, which result in wasting the reserved bandwidth or increasing the delay of excess packets. In this paper, we propose a model of optimal burst assembly for delay reduction, which minimizes the estimation error, eliminates the excess packets, and decreases the blocking probability of scheduling.


Low-Frequency Exposure Analysis Using Electric And Magnetic Field Measurements And Predictions In The Proximity Of Power Transmission Lines In Urban Areas, Hamza Feza Carlak, Şükrü Özen, Süleyman Bi̇lgi̇n Jan 2017

Low-Frequency Exposure Analysis Using Electric And Magnetic Field Measurements And Predictions In The Proximity Of Power Transmission Lines In Urban Areas, Hamza Feza Carlak, Şükrü Özen, Süleyman Bi̇lgi̇n

Turkish Journal of Electrical Engineering and Computer Sciences

In recent years, increasing energy demand has resulted in more loading in power transmission lines and correspondingly more electric and magnetic field occurrence. In this paper, electric and magnetic field levels around high voltage power transmission lines are measured and then calculated analytically by simulating the realistic case. Moreover, the field levels around these power lines have been predicted using multilayer perceptron artificial neural network (ANN) and generalized regression neural network models. Typical 154 kV power transmission line facilities of Turkey have been studied. Electric and magnetic field levels in the proximity of power transmission lines have been predicted with …


Design Of A Sharp Response Microstrip Lowpass Filter Using Taper Loaded And Radial Stub Resonators, Sohrab Majidifar, Mohsen Hayati Jan 2017

Design Of A Sharp Response Microstrip Lowpass Filter Using Taper Loaded And Radial Stub Resonators, Sohrab Majidifar, Mohsen Hayati

Turkish Journal of Electrical Engineering and Computer Sciences

This paper proposes a compact microstrip lowpass filter with a wide stopband and a very sharp roll-off. This structure consists of two dual taper-loaded resonators that are connected to the radial stubs. The resonators are described using an LC model, and its Z- and S-parameters are extracted as a function of the LC component. In the proposed filter, cut-off frequency is placed at 1.76 GHz, roll-off rate is higher than 142 dB/GHz, insertion loss is less than 0.42 dB from DC to 1.5 GHz, and rejection is greater than -24 dB from 1.88 to 15.2 GHz. The proposed filter is …


A Low Power Memoryless Rom Design Architecture For A Direct Digital Frequency Synthesizer, Salah Alkurwy, Sawal Ali, Md.Shabiul Islam, Md. Faizul Idros Jan 2017

A Low Power Memoryless Rom Design Architecture For A Direct Digital Frequency Synthesizer, Salah Alkurwy, Sawal Ali, Md.Shabiul Islam, Md. Faizul Idros

Turkish Journal of Electrical Engineering and Computer Sciences

This paper presents a novel, memoryless, read-only memory (ROM) design architecture for a direct digital frequency synthesizer (DDFS). A pipelining technique is proposed to increase the phase accumulator (PA) throughput. However, this technique increases the number of registers as the pipeline stages increase. The shifted clocking technique is used to reduce the pipelined PA registers. The wave symmetry technique is applied to store (0: $\pi $/2) of the sine wave. The ROM is partitioned into three four-bit sub-ROMs based on the angular decomposition technique and trigonometric identity. A novel approach of memoryless ROM design technique is proposed and implemented in …


Broadband High Power Stripline Compact Multisection Coupled-Line Coupler For Vhf And Uhf Applications, Mehdi Taherkhani, Arash Ahmadi Jan 2017

Broadband High Power Stripline Compact Multisection Coupled-Line Coupler For Vhf And Uhf Applications, Mehdi Taherkhani, Arash Ahmadi

Turkish Journal of Electrical Engineering and Computer Sciences

In this study, a broadband stripline multisection coupled-line coupler is designed and fabricated. The coupler has 50 dB coupling in the frequency range of 30 to 1000 MHz. The coupler is designed by cascading several unit section couplers consisting of two unequal length coupled line sections connected by different length uncoupled transmission lines. The unequal length coupled line sections with different coupling coefficients introduce a degree of freedom for bandwidth improvement and can help to reduce the overall dimensions of the multisection coupler. A lumped-element compensating circuit is used in series with the coupling port of the coupler to flatten …


Multiresponse Optimization To Improve The Torque Behavior Of An Outer-Rotor Permanent-Magnet Machine Using Gray Relational Analysis Based On The Taguchi Method, Yusuf Özoğlu Jan 2017

Multiresponse Optimization To Improve The Torque Behavior Of An Outer-Rotor Permanent-Magnet Machine Using Gray Relational Analysis Based On The Taguchi Method, Yusuf Özoğlu

Turkish Journal of Electrical Engineering and Computer Sciences

The torque behavior of an outer-rotor surface-mounted permanent-magnet machine is improved by identifying seven pertinent design variables, including rotor height. The optimal design variables are revealed by analyzing 18 experiments determined by the Taguchi method for the minimum torque ripple, minimum total harmonic distortion of the induced voltage, and maximum average torque. In addition, the optimal design variables are obtained very quickly by using gray relational analysis based on the Taguchi method with the single response of the gray relational grade instead of multiple responses. A considerable amount of multiresponse improvement is achieved according to the results of the two …


Study And Analysis Of New Pulsed Electric Field Treatment Chamber Configurations For Food Extraction, Yassine Bellebna, Hamza Bermmaki, Abedelkader Semmak, Abdelkader Chaker, Amar Tilmatine Jan 2017

Study And Analysis Of New Pulsed Electric Field Treatment Chamber Configurations For Food Extraction, Yassine Bellebna, Hamza Bermmaki, Abedelkader Semmak, Abdelkader Chaker, Amar Tilmatine

Turkish Journal of Electrical Engineering and Computer Sciences

In all treatment chamber (TC) models used in industry and in research laboratories, the product to be treated is placed in one volume unit delimited between two electrodes energized by a pulsed voltage and the electric field lines are monoaxial and perpendicular to the electrodes. The objective of this paper is to perform an experimental analysis, based on the pulsed electric field-treated beet juice extraction efficiency, of two TC new configurations. The first model is constituted of one, two, or three parallel PEF units comprising several alternate ground-HV electrodes. The treatment chambers made of Plexiglas have a square parallelepipedic shape, …


Multiobjective Distributed Model Predictive Control Method For Facility Environment Control Based On Cooperative Game Theory, Huanliang Xu, Zhaoyu Zhai, Ke Wang, Shougang Ren, Haoyun Wang Jan 2017

Multiobjective Distributed Model Predictive Control Method For Facility Environment Control Based On Cooperative Game Theory, Huanliang Xu, Zhaoyu Zhai, Ke Wang, Shougang Ren, Haoyun Wang

Turkish Journal of Electrical Engineering and Computer Sciences

In order to achieve better control performance within the facility environment, this paper proposes a distributed model predictive control method, aiming at increasing the control precision of actuators, reducing energy consumption and equipment loss at the same time. Regarding optimizing this facility environment model, it could be treated as a multiobjective optimization problem. Referring to the cooperative game theory, each objective is regarded as a gamer. Each gamer considers both its own interests and other gamers' interests to achieve a balanced result when cooperation is achieved. The simulation experiments illustrate that the proposed control method is able to adjust the …


Developing A Model And Software For Energy Efficiency Optimization In The Building Design Process: A Case Study In Turkey, Özgür Bayata, İzzetti̇n Temi̇z Jan 2017

Developing A Model And Software For Energy Efficiency Optimization In The Building Design Process: A Case Study In Turkey, Özgür Bayata, İzzetti̇n Temi̇z

Turkish Journal of Electrical Engineering and Computer Sciences

Buildings are responsible for 40% of the primary energy consumption in the world. Recent studies have revealed that the energy efficiency and environmental impact of buildings are two very important criteria to consider during the process of building design for the future of our world. By considering the initial investment cost and its importance for investors, a problem with three objective functions has emerged with 16 building energy systems and 24 construction material alternatives. The aim of this work is to develop a methodology and software to solve multiobjective building optimization problems. Thus, two different software tools have been developed …


Modeling And Control Of A Permanent-Magnet Brushless Dc Motor Drive Using A Fractional Order Proportional-Integral-Derivative Controller, Swapnil Khubalkar, Anjali Junghare, Mohan Aware, Shantanu Das Jan 2017

Modeling And Control Of A Permanent-Magnet Brushless Dc Motor Drive Using A Fractional Order Proportional-Integral-Derivative Controller, Swapnil Khubalkar, Anjali Junghare, Mohan Aware, Shantanu Das

Turkish Journal of Electrical Engineering and Computer Sciences

This paper deals with the speed control of a permanent-magnet brushless direct current (PMBLDC) motor. A fractional order PID (FOPID) controller is used in place of the conventional PID controller. The FOPID controller is a generalized form of the PID controller in which the order of integration and differentiation is any real number. It is shown that the proposed controller provides a powerful framework to control the PMBLDC motor. Parameters of the controller are found by using a novel dynamic particle swarm optimization (dPSO) method. The frequency domain pole-zero (p-z) interlacing method is used to approximate the fractional order operator. …


Sphere Decoding Algorithm For Multiuser Detection In A Distributed Antenna System, Fahad Khawaja, Alam Zaib, Shahid Khattak Jan 2017

Sphere Decoding Algorithm For Multiuser Detection In A Distributed Antenna System, Fahad Khawaja, Alam Zaib, Shahid Khattak

Turkish Journal of Electrical Engineering and Computer Sciences

In this paper, the impact of initial search radius on the complexity and performance of a sphere decoding algorithm is investigated for different user positions within a distributed antenna system. In a distributed antenna system, users can take up random positions within the cell clusters. The channel matrix can therefore take up infinitely different forms. In the presented work, a distributed antenna system with three different user positions in the cooperating cells is considered by employing different channel matrices. The effect on the complexity and performance of the sphere decoder due to the choice of the initial sphere radius is …


Effect Of Uniform And Dolph-Chebyshev Excitations On The Performance Of Circular Array Antennas, Mohan Kachalai Narasimman, Yogesh Kumar Choukiker, Srinivasa Rao Zinka, Kannadassan Dhanaraj Jan 2017

Effect Of Uniform And Dolph-Chebyshev Excitations On The Performance Of Circular Array Antennas, Mohan Kachalai Narasimman, Yogesh Kumar Choukiker, Srinivasa Rao Zinka, Kannadassan Dhanaraj

Turkish Journal of Electrical Engineering and Computer Sciences

This paper presents the design and simulation of microstrip circular antenna arrays and studies the effect of excitation with uniform and Dolph--Chebyshev distribution. With side lobe level of 20 dB and 8 microstrip circular patches, the circular array has been demonstrated with minimum grating lobes. The effects of patch and antenna array length on directivity, radiation patterns, and side lobe are also studied in detail. It is found that these antenna arrays are suitable for radar application.


Planar Inverted-F Antenna For Universal Serial Bus Dongle Applications, Hassan Tariq Chattha, Muhammad Nasir, Qamar Hussain Abbasi, Yi Huang, Saqer Saleh Aljaafreh Jan 2017

Planar Inverted-F Antenna For Universal Serial Bus Dongle Applications, Hassan Tariq Chattha, Muhammad Nasir, Qamar Hussain Abbasi, Yi Huang, Saqer Saleh Aljaafreh

Turkish Journal of Electrical Engineering and Computer Sciences

A simple planar inverted-f antenna for universal serial bus dongles covering the frequency from 1.6 GHz to more than 3.6 GHz in a single band is presented in this paper. The height of the planar inverted-f antenna is only 3 mm and the dimensions of the ground plane are set equal to the usual size of a universal serial bus dongle (20 mm $\times $ 55 mm). For further enhancement in impedance bandwidth, a rectangular strip is etched on the ground plane. The frequency bands covered by this antenna include LTE / AWS / UMTS (1700), DCS (1800), PCS / …


Cavitation Detection In Centrifugal Pumps Using Pressure Time-Domain Features, Pouya Samanipour, Javad Poshtan, Hamed Sadeghi Jan 2017

Cavitation Detection In Centrifugal Pumps Using Pressure Time-Domain Features, Pouya Samanipour, Javad Poshtan, Hamed Sadeghi

Turkish Journal of Electrical Engineering and Computer Sciences

Condition monitoring of centrifugal pumps is vital due to their crucial role in industries. One of the most prevalent faults in pumps is cavitation, which can cause mechanical faults or even failure in the pump. In this paper, an approach is suggested to detect cavitation in a centrifugal pump using time-domain analysis of the pressure signal residual. First, pressure and torque signals are obtained using a model of the electro-pump, and then pressure deviation from the pump performance curve is defined as a residual. The residual time-domain features are extracted and applied as inputs to a self-organizing map (SOM) neural …


Fractional-Order Controller Design In Frequency Domain Using An Improved Nonlinear Adaptive Seeker Optimization Algorithm, Mano Ranjan Kumar, Vishwa Deepak, Subhojit Ghosh Jan 2017

Fractional-Order Controller Design In Frequency Domain Using An Improved Nonlinear Adaptive Seeker Optimization Algorithm, Mano Ranjan Kumar, Vishwa Deepak, Subhojit Ghosh

Turkish Journal of Electrical Engineering and Computer Sciences

Two nonlinear adaptive versions of the conventional seeker optimization algorithm (SOA) have been proposed for the design of fractional-order controllers using frequency domain specifications. The highly nonlinear and undetermined nature of equations resulting from controller design specifications rules out obtaining a closed-form solution. In this regard, the controller design task has been formulated as an optimization problem and solved using modified variants of the SOA. With the nonlinear adaptation of tuning parameters, the proposed variants of the SOA increase the probability of finding global optima along with improved convergence speed. This has been achieved by incorporating exponential weighting and chaotic …


Regularized Estimation Of Hammerstein Systems Using A Decomposition-Based Iterative Instrumental Variable Method, Vikram Saini, Lillie Dewan Jan 2017

Regularized Estimation Of Hammerstein Systems Using A Decomposition-Based Iterative Instrumental Variable Method, Vikram Saini, Lillie Dewan

Turkish Journal of Electrical Engineering and Computer Sciences

This paper presents a two-step instrumental variable (IV) method to obtain the regularized and consistent parameter estimates of the Hammerstein ARMAX model based on the bilinear parameterized form. The two-step identification method consists of estimating the bilinear parameters in the first step, followed by parameter reduction in the second step. An iterative identification method is proposed, based on the idea of separating the bilinear form in the two separable forms with partial parameters and solving the decomposed model forms iteratively. The IV-based estimation is integrated into the formulated decomposed structure by introducing the instruments constructed from the estimated auxiliary model …


Investigation Of The Computational Speed Of Laguerre Network-Based Mpc In The Thermal Control Of Energy-Efficient Buildings, Ercan Atam Jan 2017

Investigation Of The Computational Speed Of Laguerre Network-Based Mpc In The Thermal Control Of Energy-Efficient Buildings, Ercan Atam

Turkish Journal of Electrical Engineering and Computer Sciences

The design of computationally efficient model predictive control (MPC) systems for the thermal control of buildings is a challenging task since long prediction horizons may be needed, which can take a significant computational time, especially when multizone buildings are considered. In this paper, we investigate the computational performance of a potential approach for this purpose, Laguerre network-based MPC (LN-MPC), for thermal control of buildings, where parameterization of control input over the prediction horizon is used to reduce the number of decision variables. The computational performance of the suggested framework with comparison to the classical MPC framework is investigated through a …


Design Of Adjustable T-Shaped And Y-Shaped Photonic Crystal Power Splitters For Tm And Te Polarizations, Mohammad Danaie, Ruhllah Nasirifar, Abbas Dideban Jan 2017

Design Of Adjustable T-Shaped And Y-Shaped Photonic Crystal Power Splitters For Tm And Te Polarizations, Mohammad Danaie, Ruhllah Nasirifar, Abbas Dideban

Turkish Journal of Electrical Engineering and Computer Sciences

In this paper, new topologies for realization of photonic crystal optical power splitters for TE and TM modes are proposed. The presented structures can be used for dividing input power with a desired ratio to output ports. The central input wavelength is designed for 1550 nm. To obtain wide-bandwidth power splitters for TE and TM modes, modified Y-shaped and T-shaped photonic crystal junctions are used. A triangular lattice of air holes and a square lattice of rods are used for Y-shaped and T-shaped platforms, respectively. For analyzing these structures, plane wave expansion and finite difference time domain methods are used. …


Power Oscillation Damping Control By Pss And Dfig Wind Turbine Under Multiple Operating Conditions, Korakot Thanpisit, Issarachai Ngamroo Jan 2017

Power Oscillation Damping Control By Pss And Dfig Wind Turbine Under Multiple Operating Conditions, Korakot Thanpisit, Issarachai Ngamroo

Turkish Journal of Electrical Engineering and Computer Sciences

Multiple operating conditions in power systems including wind power sources significantly affect the damping of low frequency oscillation modes due to diverse generating and loading conditions, random wind speeds, line outage contingencies, etc. To cope with multiple operating conditions, this paper proposes the new parameter optimization technique of the power system stabilizer (PSS) and the doubly-fed induction generator (DFIG) wind turbine with the power oscillation damper (POD) based on the probability method. Different operating conditions are randomly generated by Monte Carlo simulation. Under the generated operating points, the particle swarm optimization of PSS and POD parameters is carried out to …


A Simple Approach To Extract The Unknown Parameters Of Pv Modules, Ahmed Hussein Jan 2017

A Simple Approach To Extract The Unknown Parameters Of Pv Modules, Ahmed Hussein

Turkish Journal of Electrical Engineering and Computer Sciences

A simple and accurate technique to compute essential parameters needed for electrical characterization of photovoltaic (PV) modules is proposed. A single-diode model of PV modules, including those with series and shunt resistances, is considered accurate and simple. However, PV module datasheets provided by manufacturers provide current-voltage ($I$-$V)$ characteristics as well as the values of selected parameters at standard test conditions (STC), i.e. solar radiation of 1000 W/m$^{2}$, air temperature of 25 $^{\circ}$C, and air mass AM = 1.5. Consequently, important parameters such as series resistance ($R_{s})$, shunt resistance ($R_{sh})$, photocurrent ($I_{ph})$, and diode reverse-saturation current ($I_{o})$ are not provided by …


A Novel Microstrip Diplexer Design With Tunable Bandwidths And Switchable Channels For 4.5g Applications, Ali̇ Kürşad Görür, Pinar Öztürk Özdemi̇r, Eli̇f Güntürkün Şahi̇n, Ceyhun Karpuz Jan 2017

A Novel Microstrip Diplexer Design With Tunable Bandwidths And Switchable Channels For 4.5g Applications, Ali̇ Kürşad Görür, Pinar Öztürk Özdemi̇r, Eli̇f Güntürkün Şahi̇n, Ceyhun Karpuz

Turkish Journal of Electrical Engineering and Computer Sciences

In this paper, a novel microstrip diplexer with tunable bandwidths and switchable channels is presented by using dual-mode square loop resonators (DMSLRs). Two resonators at different electrical lengths are coupled to input and output ports with lumped capacitors, and the isolation between the output ports is optimized by means of these capacitors. In order to obtain tunable bandwidth in each channel, varactor diodes are located at the orthogonal corners of the proposed resonators. In addition, the proposed resonators have reference patch elements at the lateral arms to provide convenience of varactor diode capacitances, such as perturbation elements. Depending on the …


A Novel And Realistic Hybrid Downlink-Uplink Coupled/Decoupled Access Scheme For 5g Hetnets, Nadeem Sial, Junaid Ahmed Jan 2017

A Novel And Realistic Hybrid Downlink-Uplink Coupled/Decoupled Access Scheme For 5g Hetnets, Nadeem Sial, Junaid Ahmed

Turkish Journal of Electrical Engineering and Computer Sciences

Cell association in present day heterogeneous networks (HetNets) is still based on the technique used by homogeneous cellular networks despite power and coverage area disparities of network nodes. In ongoing policy, both uplink (UL) and downlink (DL) associations are coupled based on DL characteristics, which introduces UL-DL asymmetry and cell load imbalances. Recently, decoupled cell association, also known as downlink-uplink decoupling (DUDe), has been introduced in 3rd Generation Partnership Project (3GPP) Release 12 to improve uplink performance, load balancing, and cell capacity. In DUDe, characteristics of both DL and UL channels can be considered. By using this concept, various theoretical …


Analysis And Design Of An Invisibility Cloak Based On Transformation Optics At Microwave Frequencies, Maryam Bayati, Masood Omoomi Jan 2017

Analysis And Design Of An Invisibility Cloak Based On Transformation Optics At Microwave Frequencies, Maryam Bayati, Masood Omoomi

Turkish Journal of Electrical Engineering and Computer Sciences

Invisibility cloaks can be constructed with electromagnetic metamaterials. In this paper, structural metamaterials are used to design an invisibility cloak. To this end, transformation optics is used to design electromagnetic parameters. These parameters are selected so that when we excite the cloak its presence does not perturb radiated fields. Therefore, we formulate the electric field both at the inner and outer parts of the cloak, when the excitation source is placed both inside and outside, and we show that the scattered fields will be suppressed due to its presence. Finally, simulation results verify that the invisibility cloak is well designed …


Development And Experimental Evaluation Of A 3d Ultra-Wideband Localization System, Ali Muqaibel Jan 2017

Development And Experimental Evaluation Of A 3d Ultra-Wideband Localization System, Ali Muqaibel

Turkish Journal of Electrical Engineering and Computer Sciences

In this paper, an ultra-wideband (UWB) synthetic aperture radar system that can perform 3D localization of objects is implemented. The system consists of a moving platform that positions two UWB horn antennas. The 3D image construction is performed using the delay-sum beamforming algorithm. Experiments were performed using two data acquisition techniques, namely, background measurements technique and change detection. The former can be used for imaging stationary targets while the latter is applicable for moving objects. At different distances and orientations from the antennas, various targets were imaged. Through-wall imaging was also considered. The system is augmented with a graphical user …


An Adaptive Clustering Segmentation Algorithm Based On Fcm, Jun Yang, Yun-Sheng Ke, Mao-Zheng Wang Jan 2017

An Adaptive Clustering Segmentation Algorithm Based On Fcm, Jun Yang, Yun-Sheng Ke, Mao-Zheng Wang

Turkish Journal of Electrical Engineering and Computer Sciences

The cluster number and the initial clustering centers must be reasonably set before the analysis of clustering in most cases. Traditional clustering segmentation algorithms have many shortcomings, such as high reliance on the specially established initial clustering center, tendency to fall into the local maximum point, and poor performance with multithreshold values. To overcome these defects, an adaptive fuzzy C-means segmentation algorithm based on a histogram (AFCMH), which synthesizes both main peaks of the histogram and optimized Otsu criterion, is proposed. First, the main peaks of the histogram are chosen by operations like histogram smoothing, merging of adjacent peaks, and …


Two-Bit Transform Using Local Binary Pattern Method For Low-Complexity Block Motion Estimation, Aysun Taşyapi Çelebi̇ Jan 2017

Two-Bit Transform Using Local Binary Pattern Method For Low-Complexity Block Motion Estimation, Aysun Taşyapi Çelebi̇

Turkish Journal of Electrical Engineering and Computer Sciences

Low bit-depth representation-based motion estimation approaches have been drawing considerable attention recently, mainly because of their small hardware footprint. In this paper, a new two-bit transform using a local binary pattern (LBP) for low-complexity motion estimation is proposed. The proposed approach utilizes the LBP method to obtain two-bit representations of video frames in the binarization process. Video frames are transformed into their low bit-depth representations by the LBP and then a motion estimation process is carried out using these binary frames. A Boolean exclusive-OR operation is used to calculate the number of nonmatching points metric instead of the conventional sum …


Lifetime Maximization Of Wireless Sensor Networks With Sink Costs, Muhammed Emre Keski̇n Jan 2017

Lifetime Maximization Of Wireless Sensor Networks With Sink Costs, Muhammed Emre Keski̇n

Turkish Journal of Electrical Engineering and Computer Sciences

Balanced distribution of the energy load of the sensors is important for the elongation of wireless sensor network (WSN) lifetimes. There are four main WSN design issues affecting the energy distribution among the sensors: sensor locations, sensor activity schedules, mobile sink routes, and data flow routes. Many studies try to make energy usage more efficient through optimal determination of these design issues. However, only very few studies handle these four design issues in a combined manner. Additionally, the cost of the sinks is neglected in all studies. In this study, a mixed integer linear program is first proposed, in which …