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Full-Text Articles in Physical Sciences and Mathematics

One Pot Synthesis Of Pyridophenanthroline And Pyrrolophenanthroline Derivatives By Regioselective Reaction Between 1,7-Phenanthroline And Dialkyl Acetylenedicarboxylate: New Fused Heterocyclic Compounds, Malek Taher Maghsoodlou, Reza Heydari, Sayyed Mostafa Habibi Khorassani, Batool Tahami Pour, Ghasem Marandi, Farhad Maghfuri Jan 2011

One Pot Synthesis Of Pyridophenanthroline And Pyrrolophenanthroline Derivatives By Regioselective Reaction Between 1,7-Phenanthroline And Dialkyl Acetylenedicarboxylate: New Fused Heterocyclic Compounds, Malek Taher Maghsoodlou, Reza Heydari, Sayyed Mostafa Habibi Khorassani, Batool Tahami Pour, Ghasem Marandi, Farhad Maghfuri

Turkish Journal of Chemistry

1,7-Phenanthroline reacts with dialkyl acetylenedicarboxylate in a regioselective manner to give new macromolecules such as tetramethyl- 6aH-pyrido[1,2-i][1,7]phenanthroline-7,8,9,10-tetracarboxylate and trialkyl pyrrolo[1,2-i][1,7]phenanthroline-7,8,9-tricarboxylate derivatives.


Synthesis And Characterization Of New Symmetrical 3,6-Bis[(25,26,27- Tripropoxy-28-(3-(4-Iodophenyl) Propoxy)-P-Tert-Butyl Calix[4]Arene Ethynyl]-9h- Fluoren-9-One By Sonogashira Coupling As A Novel Precursor For Synthesis Of Quinodimethane (Qdm), Karim Akbari Dilmaghani, Fazel Nasuhi Pur Jan 2011

Synthesis And Characterization Of New Symmetrical 3,6-Bis[(25,26,27- Tripropoxy-28-(3-(4-Iodophenyl) Propoxy)-P-Tert-Butyl Calix[4]Arene Ethynyl]-9h- Fluoren-9-One By Sonogashira Coupling As A Novel Precursor For Synthesis Of Quinodimethane (Qdm), Karim Akbari Dilmaghani, Fazel Nasuhi Pur

Turkish Journal of Chemistry

Novel symmetrical 3,6-bis[(25,26,27-tripropoxy-28-(3-(4-iodophenyl)propoxy)-p-tert-butyl calix[4]arene ethynyl]-9H-fluoren-9-one with a cone conformation was synthesized by palladium-catalyzed coupling of (25,26,27-tripropoxy- 28-(3-(4-iodophenyl)propoxy)-p-tert-butyl calix[4]arene and 3,6-diethynyl-9H-fluoren-9-one. Its structure was confirmed by FT-IR, ^1H-NMR, and ^{13}C-NMR spectroscopy, and elemental analysis and positive ion FAB mass spectrometry.


A Near-Infrared Fluorescent Sensor For H^+ In Aqueous Solution And Living Cells, Aibin Wu, Liping Duan Jan 2011

A Near-Infrared Fluorescent Sensor For H^+ In Aqueous Solution And Living Cells, Aibin Wu, Liping Duan

Turkish Journal of Chemistry

A heptamethine cyanine-based sensor (1) was designed and synthesized by incorporating heptamethine cyanine fluorophore and methylpiperazine. Sensor 1 exhibited good response to the change of pH levels, and a large Stokes shift (>100 nm) was obtained. Fluorescent image experiments in living cells further demonstrated its potential applications in biological systems.


Electrochemical Impedance Spectroscopy Study On Intercalation And Anomalous Diffusion Of Alcl_4^- Ions Into Graphite In Basic Molten Salt, Ali Ehsani, Mohammad Ghasem Mahjani, Majid Jafarian Jan 2011

Electrochemical Impedance Spectroscopy Study On Intercalation And Anomalous Diffusion Of Alcl_4^- Ions Into Graphite In Basic Molten Salt, Ali Ehsani, Mohammad Ghasem Mahjani, Majid Jafarian

Turkish Journal of Chemistry

Electrochemical impedance spectroscopy (EIS) was employed to investigate diffusion of AlCl_4^- ions in basic (AlCl_3-NaCl-KCl) molten salt. Nyquist plots in different DC offset potentials showed finite and restricted aluminum ion diffusion due to insertion and blocking in the graphite electrode. The general Warburg, open Warburg, and short Warburg impedance in the complex Nyquist plot of this system showed the anomalous diffusion behavior of the ions in the graphite electrode. The diffusion coefficient of the AlCl_4^- ions was calculated from the slope of the Warburg line in a totally blocking film in the graphite electrode and was found to be 2.8 …


New Data On The Dasycladales From The Lower Eocene Of Seyitgazi Region, Eskişehir, Central Turkey, Rajka Radoicic, Nazi̇re Erdem Jan 2011

New Data On The Dasycladales From The Lower Eocene Of Seyitgazi Region, Eskişehir, Central Turkey, Rajka Radoicic, Nazi̇re Erdem

Turkish Journal of Earth Sciences

An association of Dasycladalean algae is identified from the Lower Eocene (Ilerdian-Cuisian) of the Seyitgazi area, Western Anatolia. The association consists mostly of the genus Belzungia Morellet and Anatolia n. gen. This is the first discovery of such a rich and diversified dasycladalean flora with Belzungia in the Eocene of Central Tethys. The genus Belzungia is represented by four species: Belzungia terquemi Morellet, B. silvestrii (Pfender), B. bella (Ju Ying) Radoicic and B. pfenderae n. sp. Belzungia articles consist of whorls characterized by an assemblage of laterals, in the transversal section of which, the primary laterals are distally enlarged (sub-triangular …


Late-Medieval Plagioclase-Titanaugite-Bearing Iron Slags Of The Yapraklı Area (Çankırı), Turkey, W. E. Sharp, Steven K. Mittwede Jan 2011

Late-Medieval Plagioclase-Titanaugite-Bearing Iron Slags Of The Yapraklı Area (Çankırı), Turkey, W. E. Sharp, Steven K. Mittwede

Turkish Journal of Earth Sciences

A mineralogical, mineral-geochemical and ^1^4C geochronological study of slags, previously identified as copper slags, in the Yapraklı area (Çankırı Province) of central Anatolia, has demonstrated that these are late-medieval iron slags consisting mainly of fayalite, glass, plagioclase, titanaugite, ulvöspinel and metallic iron. Because of the high lime content, relative to other medieval and Roman slags, these slags are quite anomalous in their lack of both modal and normative wüstite. Further study of these sites could shed light on the mining history and smelting methods of central Anatolia during a relatively obscure period of major socio-ethnic transition.


Geological And Palaeoseismological Evidence For Late Pleistocene−Holocene Activity On The Manisa Fault Zone, Western Anatolia, Çağlar Özkaymak, Hasan Sözbi̇li̇r, Bora Uzel, Hüsnü Serdar Akyüz Jan 2011

Geological And Palaeoseismological Evidence For Late Pleistocene−Holocene Activity On The Manisa Fault Zone, Western Anatolia, Çağlar Özkaymak, Hasan Sözbi̇li̇r, Bora Uzel, Hüsnü Serdar Akyüz

Turkish Journal of Earth Sciences

In West Anatolia near the cities of İzmir and Manisa, the historical occurrence of large earthquakes suggests the presence of important seismogenic faults. However, these faults have yet to be investigated in detail. The Manisa Fault Zone (MFZ) is an active large-scale normal fault system in this area, and thus field observations and palaeoseismological studies of this zone are important for predicting future earthquakes. Hence we sought to document geological and palaeoseismological evidence for Holocene activity on the MFZ. We performed trenching to determine the magnitude and timing of past surface-faulting events using detailed fault-trace mapping, measurements of Upper Pleistocene-Lower …


Pre-Jurassic Basement Of The Greater Caucasus: Brief Overview, Mark L. Somin Jan 2011

Pre-Jurassic Basement Of The Greater Caucasus: Brief Overview, Mark L. Somin

Turkish Journal of Earth Sciences

The main units of the Greater Caucasus pre-Jurassic basement are represented by Svanetian and North-Caucasian domains brought together tectonically. The former includes continuous Devonian to Upper Triassic marine sequence devoid of any manifestation of Variscan orogenic activity. In contrast, within the limits of the North-Caucasian domain the Variscan events are expressed in classical form. This domain is very heterogeneous and contains both metamorphosed and unmetamorphosed formations. Till recently the former was considered by most authors to be mainly Proterozoic. New geochronological data indicate that the predominant part of these complexes is Palaeozoic in their protolith age. Lithology, P/T conditions of …


New Late Ypresian (Cuisian) Rotaliids (Foraminiferida) From Central And Southern Italy And Their Biostratigraphic Potential, Andrea Benedetti, Massimo Di Carlo, Johannes Pignatti Jan 2011

New Late Ypresian (Cuisian) Rotaliids (Foraminiferida) From Central And Southern Italy And Their Biostratigraphic Potential, Andrea Benedetti, Massimo Di Carlo, Johannes Pignatti

Turkish Journal of Earth Sciences

Two new rotaliid genera and three new species are described from the Upper Ypresian of Sicily and Central Italy: Ornatorotalia spinosa n. gen. n. sp., Ornatorotalia granum n. sp. and Granorotalia sublobata n. gen. n. sp. The new taxa are all dated as SBZ 11 (middle Upper Ypresian, i.e., middle Cuisian) by the presence of Cuvillierina vallensis and alveolinid biostratigraphical markers such as Alveolina cremae, A. decastroi and A. distefanoi. The systematic position of these distinctive new taxa within the family Rotaliidae Ehrenberg, 1839 and their biostratigraphic potential are discussed.


Integrated Biostratigraphy Of Eocene Deposits In The Gubs Section (Northern Caucasus) With Special Attention To The Ypresian/Lutetian Boundary And To The Peritethyan-Tethyan Correlation, Elena Zakrevskaya, Vladimir Beniamovsky, György Less, Mária Báldi-Beke Jan 2011

Integrated Biostratigraphy Of Eocene Deposits In The Gubs Section (Northern Caucasus) With Special Attention To The Ypresian/Lutetian Boundary And To The Peritethyan-Tethyan Correlation, Elena Zakrevskaya, Vladimir Beniamovsky, György Less, Mária Báldi-Beke

Turkish Journal of Earth Sciences

The Ypresian to Priabonian Gubs river section, in the Adygean high of the northern slope of the Caucasus, is a rare locality, in whichYpresian-Lutetian representative larger benthic foraminifera coexist with planktonic Foraminifera and calcareous nannoplankton. This provides a good opportunity to apply and refine the zonal Ypresian-Lutetian scheme of the Crimean-Caucasus region, to correlate the zonal subdivision of the three most important Palaeogene groups of microfossils and to give a new insight on the position of the Ypresian/Lutetian boundary. About 50 species and subspecies of larger foraminifera, represented by orthophragmines (Discocyclina, Nemkovella, Orbitoclypeus and Asterocyclina) and nummulitids (Nummulites and Operculina) …


The Role Of The Palaeogene Adriatic Carbonate Platform In The Spatial Distribution Of Alveolinids, Katica Drobne, Vlasta Cosovic, Alan Moro, Damir Buckovic Jan 2011

The Role Of The Palaeogene Adriatic Carbonate Platform In The Spatial Distribution Of Alveolinids, Katica Drobne, Vlasta Cosovic, Alan Moro, Damir Buckovic

Turkish Journal of Earth Sciences

Sediments of the Palaeogene Adriatic carbonate platform, a distinctive palaeogeographic unit, are today exposed along the eastern Adriatic coast for a distance of 800 km and a width of 100-130 km. The large number of identified alveolinid species (69) from the Early Ypresian (Ilerdian) to the Bartonian record the dynamics of their evolution, with emphasis on the following: (1) great species diversity and great abundance in the middle Ilerdian (SBZ 7-8) followed by a sharp decline in occurrences at the Ilerdian/Cuisian transition; (2) a diversity boom in the late Ypresian (late Cuisian, SBZ 11-12) and (3) an abrupt decrease in …


Stratigraphy, Sedimentology And Palynology Of The Neogene-Pleistocene(?) Rocks Around Akçaşehir- Tire-İzmir (Küçük Menderes Graben, Western Anatolia), Tahi̇r Emre, Meti̇n Tavlan, Mehmet Serkan Akki̇raz, İsmai̇l İşi̇ntek Jan 2011

Stratigraphy, Sedimentology And Palynology Of The Neogene-Pleistocene(?) Rocks Around Akçaşehir- Tire-İzmir (Küçük Menderes Graben, Western Anatolia), Tahi̇r Emre, Meti̇n Tavlan, Mehmet Serkan Akki̇raz, İsmai̇l İşi̇ntek

Turkish Journal of Earth Sciences

The basement rocks located in the central part of the southern edge of the Küçük Menderes Graben, around Akçaşehir-Tire are composed of marbles, schists, gneisses and metagabbros of the Ödemiş-Kiraz submassif of the Menderes Massif, and schists, marbles and meta-olistostromes of the Cycladic Complex. The basement is unconformably overlain by Neogene-Quaternary continental sediments. These continental basin fills are comprised of the Ayaklıkırı Formation, the Aydoğdu Formation and alluvium that unconformably overlies them. The Lower-Upper Miocene Ayaklıkırı Formation consists of lacustrine and fluvial deposits. The Plio-Pleistocene (?) Aydoğdu Formation is made up of alluvial fan deposits. Vast plains of alluvium cover …


The Gümüldür Fire Opal: Mode Of Occurrence And Mineralogical Aspects, Zeki̇ye Karacik, Şengül Can Genç, Recep Fahri̇ Esenli̇, Gülteki̇n Göller Jan 2011

The Gümüldür Fire Opal: Mode Of Occurrence And Mineralogical Aspects, Zeki̇ye Karacik, Şengül Can Genç, Recep Fahri̇ Esenli̇, Gülteki̇n Göller

Turkish Journal of Earth Sciences

Five types of silica polymorphs have been identified in dacitic volcanics from the Gümüldür region of western Anatolia, Turkey. Two of them are micro-quartz and disordered cristobalite (opal-C) that occur within the groundmass of the dacitic volcanic rocks. The others are pore-filling opal nodules including mainly massy opal-CT (opal-CTM) and rarely lussatite (opal-CTL) and amorphous opal (opal-A). Red and orange opal nodules are very similar to the gemologically well-known fire opals. Results of structural, chemical and thermal studies of the Gümüldür opals reveal their origin and mode of occurrence. Opal-CTM has gel-like or nano-grain texture and opal-CTL has a fibrous, …


Geochemical And Sr-Nd Isotopic Characteristics Of Post-Collisional Calc-Alkaline Volcanics In The Eastern Pontides (Ne Turkey), Abdullah Kaygusuz, Mehmet Arslan, Wolfgang Siebel, Cüneyt Şen Jan 2011

Geochemical And Sr-Nd Isotopic Characteristics Of Post-Collisional Calc-Alkaline Volcanics In The Eastern Pontides (Ne Turkey), Abdullah Kaygusuz, Mehmet Arslan, Wolfgang Siebel, Cüneyt Şen

Turkish Journal of Earth Sciences

Major, trace element, K-Ar age and Sr-Nd isotopic data are presented for the Eocene Torul volcanics in the eastern Pontide orogenic belt (NE Turkey). The studied rocks are composed of basaltic andesitic, andesitic, trachyandesitic, and minor trachydacitic lavas associated with their pyroclastics. These rocks contain plagioclase (An2-44), hornblende (Mg#= 0.78-0.98), clinopyroxene (Wo43-46 En41-43 Fs10-15), biotite, quartz, and minor sanidine phenocrysts. K-Ar ages on hornblendes ages range from 43.99 (±2.59) to 33.45 (±2.32) Ma, within the Middle to Late Eocene. The volcanic rocks show calc-alkaline affinities and have medium to high K contents. They are enriched in large ion lithophile (LILE) …


Design And Evaluation Of A Query-Based Jamming Detection Algorithm For Wireless Sensor Networks, Murat Çakiroğlu, Ahmet Turan Özceri̇t Jan 2011

Design And Evaluation Of A Query-Based Jamming Detection Algorithm For Wireless Sensor Networks, Murat Çakiroğlu, Ahmet Turan Özceri̇t

Turkish Journal of Electrical Engineering and Computer Sciences

Jamming attacks, which are the main cause of data corruption and network blockages in wireless sensor networks (WSNs), are one of the most serious threats for WSNs. This type of attack not only blocks the ongoing communication in the network, but also causes the wireless nodes to exhaust their energy much earlier than expected. A countermeasure must be deployed against jamming attacks, especially in military and medical applications in which security breaches cannot be tolerated. In this paper, we have designed a new query-based jamming detection algorithm (QUJDA) to detect jamming attacks occurring in WSNs. QUJDA is an attack detection …


Line Detection With Adaptive Random Samples, Ali̇ Cafer Gürbüz Jan 2011

Line Detection With Adaptive Random Samples, Ali̇ Cafer Gürbüz

Turkish Journal of Electrical Engineering and Computer Sciences

This paper examines the detection of parameterized shapes in multidimensional noisy grayscale images. A novel shape detection algorithm utilizing random sample theory is presented. Although the method can be generalized, line detection is detailed. Each line in the image corresponds to a point in the line parameter space. The method creates hypothesis lines by randomly selecting parameter space points and tests the surrounding regions for acceptable linear features. The information obtained from each randomly selected line is used to update the parameter distribution, which reducesi the required number of random trials. The selected lines are re-estimated within a smaller search …


Design And Implementation Of A Voice-Controlled Prosthetic Hand, Musa Hakan Asyali, Mustafa Yilmaz, Mahmut Tokmakçi, Kanber Sedef, Beki̇r Hakan Aksebzeci̇, Rohin Mittal Jan 2011

Design And Implementation Of A Voice-Controlled Prosthetic Hand, Musa Hakan Asyali, Mustafa Yilmaz, Mahmut Tokmakçi, Kanber Sedef, Beki̇r Hakan Aksebzeci̇, Rohin Mittal

Turkish Journal of Electrical Engineering and Computer Sciences

Current hand prostheses are mostly driven by electromyography (EMG) signal, and existing experiments have proved that multichannel EMG signal controls are not suitable due to early fatigue problems and high effort requirements to perform even simple activities. Therefore, in this study we present a new voice-controlled active hand prosthesis to perform several basic tasks. We first designed a novel multifingered prosthetic hand with the ability of picking up and releasing objects. The prosthetic hand employs 3 DC motors and gears to transfer motion to the linked iparts of the fingers. We used flexible thin-film resistive force sensors at the fingertips …


Analysis Of Frequency Characteristics Of Electrical Arcs On The Insulating Sheath Of The Adss Fiber Optic Cables, Cengi̇z Polat Uzunoğlu, İbrahi̇m Güneş, Mukden Uğur Jan 2011

Analysis Of Frequency Characteristics Of Electrical Arcs On The Insulating Sheath Of The Adss Fiber Optic Cables, Cengi̇z Polat Uzunoğlu, İbrahi̇m Güneş, Mukden Uğur

Turkish Journal of Electrical Engineering and Computer Sciences

The insulating outer-sheath of ADSS (All dielectric self supporting) cables used on high voltage transmission lines are often subjected to various environmental effects. The ageing process of cable sheath can be investigated by using the dry-band arcing test method under laboratory conditions. Dry-band arcing is the most common technique to determine the ageing period of insulating materials. Environmental effects such as rain, humidity, dew and ice produce various amounts of wet regions on the cable surface. Electrical arcs and hence degradations are occurred on the cable surface due to the enhanced electrical field with formation of wet regions. In this …


Adaptive Wiener-Turbo Systems With Jpeg & Bit Plane Compressions In Image Transmission, Ersi̇n Göse Jan 2011

Adaptive Wiener-Turbo Systems With Jpeg & Bit Plane Compressions In Image Transmission, Ersi̇n Göse

Turkish Journal of Electrical Engineering and Computer Sciences

In recent years, for transmission of 2D colored images over the fading channels, a new scheme has been denoted as ``adaptive Wiener-turbo systems with JPEG & bit plane compressions'' (AW-TSwJBC). In this paper, the performance of AW-TSwJBC is introduced over Rician and Rayleigh fading channels. We benefited from the neighborhood relation of pixels for each color plane by using a new iterative block, the ``adaptive Wiener-turbo'' scheme, which employs a turbo decoder, JPEG encoder/decoders, and adaptive Wiener filtering. In our approach, we could also alter compression ratios due to the importance of the image to be transferred. Based on the …


A Novel And Efficient Algorithm For Adaptive Filtering: Artificial Bee Colony Algorithm, Nurhan Karaboğa, Mehmet Bahadir Çeti̇nkaya Jan 2011

A Novel And Efficient Algorithm For Adaptive Filtering: Artificial Bee Colony Algorithm, Nurhan Karaboğa, Mehmet Bahadir Çeti̇nkaya

Turkish Journal of Electrical Engineering and Computer Sciences

The uni-modal error surfaces and intrinsic stable behaviors of adaptive finite impulse response (FIR) filters make gradient based algorithms very effective in the design of these filters. Gradient based design methods are well developed for the design of adaptive FIR filters and widely applied to the distinct areas such as noise cancellation, system identification and channel equalization. However, the studies on adaptive infinite impulse response (IIR) filters are not as common as adaptive FIR filters since the stability during the adaptation process may not be ensured in some applications, and the convergence to the optimal design is not always guaranteed …


New Srco With Explicit Current-Mode Output Using Two Ccs And Grounded Capacitors, D R. Bhaskar, Kasim K. Abdalla, Raj Senani Jan 2011

New Srco With Explicit Current-Mode Output Using Two Ccs And Grounded Capacitors, D R. Bhaskar, Kasim K. Abdalla, Raj Senani

Turkish Journal of Electrical Engineering and Computer Sciences

A new Grounded-Capacitor Single Resistance Controlled Sinusoidal Oscillator (SRCO) with explicit current output using two Current Conveyors (CCs) and five passive elements is presented. The proposed circuit offers (i) independent control of condition of oscillation and frequency of oscillation, (ii) low active and passive sensitivities, (iii) use of both the grounded capacitors (suitable for IC implementation) and (iv) reasonably good frequency stability. The workability of the proposed configuration has been confirmed by the PSPICE simulations.


Online Speed Control Of A Brushless Ac Servomotor Based On Artificial Neural Networks, Si̇bel Partal, İbrahi̇m Şenol, Ahmet Faruk Bakan, Kamuran Nur Beki̇roğlu Jan 2011

Online Speed Control Of A Brushless Ac Servomotor Based On Artificial Neural Networks, Si̇bel Partal, İbrahi̇m Şenol, Ahmet Faruk Bakan, Kamuran Nur Beki̇roğlu

Turkish Journal of Electrical Engineering and Computer Sciences

In this paper, an alternative approach to speed estimation of brushless AC servomotors is presented. Speed control is realized in the following steps. First, the servomotor was mathematically modelled; the driver system was designed and speed control of the servomotor was accomplished with feedback. Next, a network structure representing the electrical and mechanical properties of the servomotor was built via Artificial Neural Network (ANN) and trained with the results of the first step. The weights obtained from the neural nwork training were inserted into the control algorithm in accordance with the ANN. Finally, speed estimation was achieved based on the …


Obtaining The Secondary Impedance Of Single-Sided Linear Induction Motor With A Double Layer Reaction Rail: A New Approach, Ali̇ Suat Gerçek, Vedat Mehmet Karsli Jan 2011

Obtaining The Secondary Impedance Of Single-Sided Linear Induction Motor With A Double Layer Reaction Rail: A New Approach, Ali̇ Suat Gerçek, Vedat Mehmet Karsli

Turkish Journal of Electrical Engineering and Computer Sciences

In the performance calculations of single-sided linear induction motor (SLIM),the equivalent circuit technique (ECT) is used. In this paper, a new approach is proposed for obtaining the secondary impedance of single-sided linear induction motor (SLIM) with a double layer reaction rail by using the layered secondary model. The proposed method improves the ECT technique by considering the saturation effect and the non-linear complex equivalent relative permeability. This study also examines the contributions of other electromagnetic effects, such as longitudinal end effect and transverse edge effect as well. Our method is applied to the SLIM and computed results of the method …


Electromagnetic Scattering From Layered Strip Geometries: The Method Of Moments Study With The Sinc Basis, Taner Oğuzer, Fadil Kuyucuoğlu, İbrahi̇m Avgin Jan 2011

Electromagnetic Scattering From Layered Strip Geometries: The Method Of Moments Study With The Sinc Basis, Taner Oğuzer, Fadil Kuyucuoğlu, İbrahi̇m Avgin

Turkish Journal of Electrical Engineering and Computer Sciences

Electromagnetic scattering from strips of layers is analyzed using the method of moments (MoM) for both polarizations in spatial domain with the sinc-type orthogonal sets as basis and testing functions. We exploited the sinc function's properties of exponential convergence, the orthogonality, easy convolution and better handling of singular kernels in MoM procedure resulting in fast performance and reasonable accuracy even in ordinary MoM treatment. We transferred the integral of the Hankel function multiplied by sinc functions to Hankel function introducing a slight error with large band width. We proved that this relative error during the generation of the main matrix …


An Effective Real Coded Ga Based Fuzzy Controller For Speed Control Of A Bldc Motor Without Speed Sensor, Ömer Aydoğdu, Ramazan Akkaya Jan 2011

An Effective Real Coded Ga Based Fuzzy Controller For Speed Control Of A Bldc Motor Without Speed Sensor, Ömer Aydoğdu, Ramazan Akkaya

Turkish Journal of Electrical Engineering and Computer Sciences

In this study, an effective Real Coded Genetic Algorithm (GA) based optimal fuzzy controller is proposed. The fuzzy controller is used for sensorless speed control of a Brushless DC (BLDC) motor in DSP based application system. The advantages of adopting a real coded GA for the design and optimization of fuzzy controllers, which have a great deal of design and optimization parameters, are analyzed. Having accomplished optimization of developed fuzzy control system, a multi-objective performance index has been defined and it has been used as an objective function to be minimized in the real coded GA. Thus, the system can …


Low-Complexity Parameters Estimator For Multiple 2d Domain Incoherently Distributed Sources, Xiansheng Guo, Qun Wan, Xiaofeng Shen, Heng Dou Jan 2011

Low-Complexity Parameters Estimator For Multiple 2d Domain Incoherently Distributed Sources, Xiansheng Guo, Qun Wan, Xiaofeng Shen, Heng Dou

Turkish Journal of Electrical Engineering and Computer Sciences

A new low-complexity parameters estimator for multiple two-dimensional (2D) domain incoherently distributed (ID) sources is presented. One 2D domain ID source is parameterized with four parameters, the central azimuth direction-of-arrival (DOA), azimuth angular spread, central elevation DOA and elevation angular spread. Based on the eigenstructure between the steering matrix and signal subspace, an average total least-squares via rotational invariance technique (TLS-ESPRIT) is used to estimate the central elevation DOA, and then a generalized multiple signal classification (GMUSIC) algorithm is derived to estimate the central azimuth DOA. Utilizing preliminary estimates obtained at a pre-processing stage, the angular spread parameters can be …


On The Existence Of Common Lyapunov Functions For Consensus Algorithms Based On Averaging, Mehmet Akar, Robert Shorten Jan 2011

On The Existence Of Common Lyapunov Functions For Consensus Algorithms Based On Averaging, Mehmet Akar, Robert Shorten

Turkish Journal of Electrical Engineering and Computer Sciences

This paper addresses distributed deterministic consensus algorithms based on averaging. We relate the conditions for achieving consensus to the existence of a common norm for a set of row-stochastic matrices associated with the original set of averaging matrices. For a system to achieve consensus, it is shown that this associated set of matrices should have a Common Lyapunov Function, even if the original set might not have one.


Ecg Denoising On Bivariate Shrinkage Function Exploiting Interscale Dependency Of Wavelet Coefficients, Sema Kayhan, Ergun Erçelebi̇ Jan 2011

Ecg Denoising On Bivariate Shrinkage Function Exploiting Interscale Dependency Of Wavelet Coefficients, Sema Kayhan, Ergun Erçelebi̇

Turkish Journal of Electrical Engineering and Computer Sciences

This paper presents a new method for electrocardiogram (ECG) denoising based on bivariate shrinkage functions exploiting the interscale dependency of wavelet coefficients. Most nonlinear thresholding methods based on wavelet transform denoising assume that the wavelet coefficients are independent. However, wavelet coefficients of ECG signals have significant dependencies. In this paper, we proposed a new method by considering the dependencies between the coefficients and their parents in detail on a bivariate shrinkage function for denoising of an ECG signal corrupted by different types of noises, such as muscle artifact noise, electrode motion, and white noise. In real-time applications, reduction of computational …


Decentralized Robust Load-Frequency Control Of Power System Based On Quantitative Feedback Theory, Aidin Sakhavati, Gevork Gharehpetian, Seyed Hossein Hosseini Jan 2011

Decentralized Robust Load-Frequency Control Of Power System Based On Quantitative Feedback Theory, Aidin Sakhavati, Gevork Gharehpetian, Seyed Hossein Hosseini

Turkish Journal of Electrical Engineering and Computer Sciences

This paper aims at investigating the problem of Load Frequency Control (LFC) in interconnected power systems in order to obtain robustness against uncertainties. A design method for a robust controller, based on Quantitative Feedback Theory (QFT), has been presented in this paper. For a two-area power system, the simulation results show that the system response with the proposed QFT controller exhibits transient response beyond PI controllers. It is also shown that the transient response of the tie line power can also be improved.


A Unified Series-Parallel Active Filter System For Nonperiodic Disturbances, Mehmet Uçar, Şule Özdemi̇r, Engi̇n Özdemi̇r Jan 2011

A Unified Series-Parallel Active Filter System For Nonperiodic Disturbances, Mehmet Uçar, Şule Özdemi̇r, Engi̇n Özdemi̇r

Turkish Journal of Electrical Engineering and Computer Sciences

This paper presents a 3-phase, 4-wire unified series-parallel active filter (USPAF) system for periodic and nonperiodic disturbance compensation using a generalized nonactive power theory. The USPAF system consists of a series active filter (AF), parallel AF, and split DC-link capacitors with the midpoint of the DC-link connected to the neutral wire. The generalized nonactive power theory is applicable to single-phase or multiphase, sinusoidal or nonsinusoidal, periodic or nonperiodic, and balanced or unbalanced electrical systems. The theory was implemented previously in a parallel AF. In this study, the USPAF system is proposed to compensate for the nonsinusoidal and nonperiodic currents and …