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A Novel Expression For Resonant Length Obtained By Using Artificial Bee Colony Algorithm In Calculating Resonant Frequency Of C-Shaped Compact Microstrip Antennas, Ali̇ Akdağli, Mustafa Berkan Bi̇çer, Seda Ermi̇ş Jan 2011

A Novel Expression For Resonant Length Obtained By Using Artificial Bee Colony Algorithm In Calculating Resonant Frequency Of C-Shaped Compact Microstrip Antennas, Ali̇ Akdağli, Mustafa Berkan Bi̇çer, Seda Ermi̇ş

Turkish Journal of Electrical Engineering and Computer Sciences

This paper presents a novel and simple expression for resonant length to calculate the resonant frequency of C-shaped compact microstrip antennas operating on UHF band applications. C-shaped compact microstrip antennas with different physical dimensions and electrical parameters were simulated by means of a software package that employs the method of finite difference time domain. With the aid of the artificial bee colony algorithm, an expression for the resonant length depending on physical dimensions was constructed by using simulation data. The resonant length expression provided less than 1.6% error on average over the simulated 144 antennas. A comparison between the results …


Ellipsoid Based L_2 Controller Design For Lpv Systems With Saturating Actuators, İbrahi̇m Beklan Küçükdemi̇ral, Levent Ucun, Yavuz Eren, Haluk Görgün, Gali̇p Cansever Jan 2011

Ellipsoid Based L_2 Controller Design For Lpv Systems With Saturating Actuators, İbrahi̇m Beklan Küçükdemi̇ral, Levent Ucun, Yavuz Eren, Haluk Görgün, Gali̇p Cansever

Turkish Journal of Electrical Engineering and Computer Sciences

This paper addresses the L_2 gain control problem for disturbance attenuation in Linear Parameter Varying (LPV) Systems having saturating actuators when the system is subjected to L_2 disturbances. In the presented method, saturating actuator is expressed analytically with a convex hull of some linear feedback which let us construct L_2 control problem via Linear Matrix Inequalities (LMIs) which are obtained by some ellipsoids. It is shown that the stability and disturbance rejection capabilities of the control system are all measured by means of these nested ellipsoids where the inner ellipsoid covers the initial conditions for states whereas the outer ellipsoid …


Model Predictive Controller Design Of Hydrocracker Reactors, Di̇la Gökçe Jan 2011

Model Predictive Controller Design Of Hydrocracker Reactors, Di̇la Gökçe

Turkish Journal of Electrical Engineering and Computer Sciences

This study summarizes the design of a Model Predictive Controller (MPC) in Tüpraş, İzmit Refinery Hydrocracker Unit Reactors. Hydrocracking process, in which heavy vacuum gasoil is converted into lighter and valuable products at high temperature and pressure is described briefly. Controller design description, identification and modeling studies are examined and the model variables are presented. WABT (Weighted Average Bed Temperature) equalization and conversion increase are simulated, results are discussed.


Cover And Contents Jan 2011

Cover And Contents

Turkish Journal of Electrical Engineering and Computer Sciences

No abstract provided.


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 …


Papr Reduction Using Artificial Bee Colony Algorithm In Ofdm Systems, Necmi̇ Taşpinar, Dervi̇ş Karaboğa, Mahmut Yildirim, Bahri̇ye Akay Jan 2011

Papr Reduction Using Artificial Bee Colony Algorithm In Ofdm Systems, Necmi̇ Taşpinar, Dervi̇ş Karaboğa, Mahmut Yildirim, Bahri̇ye Akay

Turkish Journal of Electrical Engineering and Computer Sciences

Partial transmit sequence (PTS) is an attractive scheme for peak-to-average power ratio (PAPR) reduction in orthogonal frequency division multiplexing (OFDM) systems, but its high computational complexity to find optimum phase factors is the main drawback. In this paper, we propose PTS based on an artificial bee colony (ABC) algorithm (ABC-PTS) for reducing the computational complexity of the PTS in the OFDM system. The ABC-PTS was compared to conventional PTS using a random search strategy (RS-PTS) and optimum PTS. In addition, the bit error rate (BER) performance of the ABC-PTS was shown when a high power amplifier (HPA) was used for …


Stray Magnetic Field Distributed Around A Pmsm, Ali̇ Ahmed Adam, Kayhan Gülez, Seli̇m Köroğlu Jan 2011

Stray Magnetic Field Distributed Around A Pmsm, Ali̇ Ahmed Adam, Kayhan Gülez, Seli̇m Köroğlu

Turkish Journal of Electrical Engineering and Computer Sciences

In this work, the low frequency electromagnetic emission from permanent magnet synchronous motors is studied. The main objective is to provide a safety region for humans in the vicinity of these motors, especially as these motors are now being used widely in inhabited areas, where high flux densities are expected. In this study, a new proposed equivalent magnetic circuit is used to estimate the stray fields at the surface of the motor. The analysis showed that the emission of the stray field in the radial direction depends on the permeability of the stator body. Low values of permeability may result …


Cover And Contents Jan 2011

Cover And Contents

Turkish Journal of Electrical Engineering and Computer Sciences

No abstract provided.


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.


Imitation Of Basic Hand Preshapes By Fluid Based Method: Fluidics Formation Control, Umut Ti̇lki̇, İsmet Erkmen, Aydan Müşerref Erkmen Jan 2011

Imitation Of Basic Hand Preshapes By Fluid Based Method: Fluidics Formation Control, Umut Ti̇lki̇, İsmet Erkmen, Aydan Müşerref Erkmen

Turkish Journal of Electrical Engineering and Computer Sciences

In this paper, a new approach is developed, avoiding the correspondence problem caused by the difference in embodiment between imitator and demonstrator in imitation learning. In our work, the imitator is a fluidic system of dynamics totally different than the imitatee, which is a human performing hand gestures. The fluidic system is composed of fluid particles, which are used for the discretization of the problem domain. In this work, we demonstrate the fluidics formation control so as to imitate by observation basic hand preshaping features. Our fluidic formation control is based on setting suitable parameters of Smoothed Particle Hydrodynamics (SPH), …


Four Quadrant Fgmos Analog Multiplier, Si̇nem Keleş, Hulusi̇ Hakan Kuntman Jan 2011

Four Quadrant Fgmos Analog Multiplier, Si̇nem Keleş, Hulusi̇ Hakan Kuntman

Turkish Journal of Electrical Engineering and Computer Sciences

A novel four-quadrant analog multiplier using floating gate MOS (FGMOS) transistors operating in the saturation region is presented. The drain current is proportional to the square of the weighted sum of the input signals. This square law characteristic of the FGMOS transistor is used to implement the quarter square identity by utilizing only six FGMOS transistors. The main features of this remarkably simple multiplier circuit configuration are the large input signal range equal to 100% of the supply voltage, nonlinearity of 0.0081%, bandwidth of 1.4--1.5 Ghz and THD of maximum 2.67% (while the inputs are at their maximum values).


Cover And Contents Jan 2011

Cover And Contents

Turkish Journal of Electrical Engineering and Computer Sciences

No abstract provided.


Reaction Dynamics Of Br + Hd: Quantum Wave Packet On Three Potential Energy Surfaces, Qing Song, Wei-Long Quan, Tian-Jun Feng Jan 2011

Reaction Dynamics Of Br + Hd: Quantum Wave Packet On Three Potential Energy Surfaces, Qing Song, Wei-Long Quan, Tian-Jun Feng

Turkish Journal of Chemistry

The initial state-resolved reaction probabilities, reaction cross-sections, and rate constants of the reaction Br + HD are computed on 3 potential energy surfaces (denoted as e-LEPS, MB2, and MB3, respectively) by carrying out quantum time-dependent wave packet calculations. The results show that the reactivity of Br + HD on MB3 is much stronger than that on e-LEPS and somewhat weaker than that on MB2. Both of the vibrational and the rotational excitation of reagent HD enhance the reaction, which depends on the PESs and the strongest enhancement effects are on e-LEPS.


Exotic Localized Structures Based On The Symmetrical Lucas Function Of The (2+1)-Dimensional Generalized Nizhnik-Novikov-Veselov System, Emad A-B. Abdel-Salam, Zeid I. A. Al-Muhiameed Jan 2011

Exotic Localized Structures Based On The Symmetrical Lucas Function Of The (2+1)-Dimensional Generalized Nizhnik-Novikov-Veselov System, Emad A-B. Abdel-Salam, Zeid I. A. Al-Muhiameed

Turkish Journal of Physics

Based on the Lucas Riccati method and a linear variable separation method, new variable separation solutions of the (2+1)-dimensional generalized Nizhnik-Novikov-Veselov system are derived. Then, we give a positive answer for the following question: Are there any localized excitations derived by the use of another functions? For this purpose, some attention will be paid to dromion, peakon, multi dromion-solitoff excitations, regular fractal dromions, stochastic fractal dromion structure and combined structures including bell-like compactons, peakon-like compactons and compacton-like semi-foldons based on the golden main. With the help of the modified Weierstrass function, we discuss the stochastic fractal dromion structure both analytically …


Cover And Contents Jan 2011

Cover And Contents

Turkish Journal of Biology

No abstract provided.


Left Main Coronary Calcification Mimicking Dissection: Multislice Computed Tomography Saves The Patient From Emergent Surgery, Tahi̇r Durmaz, Telat Keleş, Ni̇hal Akar Bayram, Meli̇ke Ruşen Meti̇n, Hüseyi̇n Ayhan, Engi̇n Bozkurt Jan 2011

Left Main Coronary Calcification Mimicking Dissection: Multislice Computed Tomography Saves The Patient From Emergent Surgery, Tahi̇r Durmaz, Telat Keleş, Ni̇hal Akar Bayram, Meli̇ke Ruşen Meti̇n, Hüseyi̇n Ayhan, Engi̇n Bozkurt

Turkish Journal of Medical Sciences

Diagnosis of coronary artery dissection using multislice computed tomography (MSCT), particularly of the left main coronary artery (LMCA), has been rarely reported. Coronary anatomy and calcification can be evaluated with MSCT. Herein, we present a case with acute coronary syndrome and coronary artery calcification mimicking the LMCA dissection detected by MSCT.


Cover And Contents Jan 2011

Cover And Contents

Turkish Journal of Medical Sciences

No abstract provided.


Effects Of Plasma Lipids And Smoking On Cognitive Function, Oğuz Teki̇n, Adem Özkara, Burcu Yanik, M. Ramazan Yi̇ği̇toğlu, Ati̇lla İlhan, Erkan Kibrisli, İrfan Şencan, Meti̇n Canbal Jan 2011

Effects Of Plasma Lipids And Smoking On Cognitive Function, Oğuz Teki̇n, Adem Özkara, Burcu Yanik, M. Ramazan Yi̇ği̇toğlu, Ati̇lla İlhan, Erkan Kibrisli, İrfan Şencan, Meti̇n Canbal

Turkish Journal of Medical Sciences

To research the relations between plasma lipids and smoking as they affect cognitive functions. Some studies have suggested a relationship between plasma cholesterol concentration, smoking, and the frequency of cognitive disturbances. Our hypothesis was that plasma lipids and smoking are related to cognitive impairment. Materials and methods: The plasma lipid profiles and cognitive functions of the subjects were measured and the relations among plasma lipid levels, smoking, and cognitive functions were observed. The study was performed on subjects with no history of chronic disease. Mental status was evaluated by the mini-mental state examination (MMSE) in patients over 40 years of …


Cover And Contents Jan 2011

Cover And Contents

Turkish Journal of Medical Sciences

No abstract provided.


Development And Validation Of The Turkish Version Of The Mnread Visual Acuity Charts, Şefay Aysun İdi̇l, Deni̇z Çalişkan, Namik Bariş İdi̇l Jan 2011

Development And Validation Of The Turkish Version Of The Mnread Visual Acuity Charts, Şefay Aysun İdi̇l, Deni̇z Çalişkan, Namik Bariş İdi̇l

Turkish Journal of Medical Sciences

To design and validate a Turkish version of the MNREAD acuity charts. Materials and methods: A vocabulary was created using high-frequency words that appear in Turkish schoolbooks used by 8-year-old children in the third grade. In total, 125 sentences were generated. The sentences were read by 2 groups (20 adults and 20 primary school students), and reading time and verbal mistakes were recorded. Thereafter, persistent verbal mistakes and sentences with extreme high and low mean reading speeds were excluded. Finally, the validity of the participants' reading speed as measured with the MNREAD Turkish version was determined by comparing it to …


Can Obstructive Apnea And Hypopnea During Sleep Be Differentiated By Using Electroencephalographic Frequency Bands? Statistical Analysis Of Receiver-Operator Curve Characteristics, Erdem Uçar, Necdet Süt, Tevfi̇k Gülyaşar, İlhan Umut, Levent Öztürk Jan 2011

Can Obstructive Apnea And Hypopnea During Sleep Be Differentiated By Using Electroencephalographic Frequency Bands? Statistical Analysis Of Receiver-Operator Curve Characteristics, Erdem Uçar, Necdet Süt, Tevfi̇k Gülyaşar, İlhan Umut, Levent Öztürk

Turkish Journal of Medical Sciences

To investigate whether electroencephalographic (EEG) frequency bands are applicable in distinguishing abnormal respiratory events such as obstructive apnea and hypopnea in patients with sleep apnea. Materials and methods: The polysomnographic recordings of 20 patients were examined retrospectively. EEG record segments were taken from C4-A1 and C3-A2 channels and were analyzed with software that uses digital signal processing methods, developed by the study team. Percentage values of delta, theta, alpha, and beta frequency bands were evaluated through discriminant and receiver-operator curve (ROC) analysis to distinguish between apneas and hypopneas. Results: For the C4-A1 channel, delta (%) provided the highest discriminative value …


An Efficient Method For Stable Transfection Of Mouse Myogenic C2c12 Cell Line Using A Nonviral Transfection Approach, Mehmet Deni̇z Akyüz, Burcu Hayta, Pervi̇n Ruki̇ye Di̇nçer Jan 2011

An Efficient Method For Stable Transfection Of Mouse Myogenic C2c12 Cell Line Using A Nonviral Transfection Approach, Mehmet Deni̇z Akyüz, Burcu Hayta, Pervi̇n Ruki̇ye Di̇nçer

Turkish Journal of Medical Sciences

To describe in detail the use of the T-REx^{TM} System (a tetracycline-regulated mammalian expression system; Invitrogen) for rapid, easy, and effective generation of stable C2C12 cell clones. Tetracycline-inducible stable cell lines are useful tools to study the function of various genes in different types of mammalian cells. However, the generation of stable cell lines is a time-consuming, technically difficult, and expensive process. Materials and methods: Generation of a stable C2C12 cell line was performed by stable transfection of the cells with the pcDNA6/TR plasmid vector, which contains the tetracycline repressor and the blasticidin drug resistance genes. The establishment of the …


Effects Of Dietary Fish Oil Replacement By Cottonseed Oil On Growth Performance And Fatty Acid Composition Of Rainbow Trout (Oncorhynchus Mykiss), Müjde Güler, Mustafa Yildiz Jan 2011

Effects Of Dietary Fish Oil Replacement By Cottonseed Oil On Growth Performance And Fatty Acid Composition Of Rainbow Trout (Oncorhynchus Mykiss), Müjde Güler, Mustafa Yildiz

Turkish Journal of Veterinary & Animal Sciences

The aim of the present study was to determine the effects of replacing fish oil (FO) with cottonseed oil (CSO), as an alternative plant lipid source in diets for rainbow trout (89.3 ± 1.1 g mean individual weight), on the growth and fatty acid composition of fish. As a control diet, 5 experimental diets were formulated with pure FO and with partial or complete (25%, 50%, 75%, or 100% CSO, respectively) replacement of FO with CSO. The fish were fed 2% of their body weight per day for 60 days at an average water temperature of 10.2 °C. At the …


Distribution And Allometry Of The Knobby Swimcrab,Macropipus Tuberculatus (Roux, 1830) (Brachyura, Portunidae) In The Strait Of Sicily (Mediterranean Sea), Giandomenico Nardone, Sergio Ragonese Jan 2011

Distribution And Allometry Of The Knobby Swimcrab,Macropipus Tuberculatus (Roux, 1830) (Brachyura, Portunidae) In The Strait Of Sicily (Mediterranean Sea), Giandomenico Nardone, Sergio Ragonese

Turkish Journal of Zoology

Distribution and biometric information for Macropipus tuberculatus of the Strait of Sicily were obtained via an experimental bottom trawl survey carried out in 2000. The species occurred with low frequency (20%) and abundance (365 specimens), showing a scattered spatial distribution, split in 2 preferential depth levels (90-160 m and 230-460 m). Males were larger and more abundant than females. The carapace length width relationship was allometric positive (b > 1), and the carapace length weight relationship was isometric (b = 3).


Cover And Contents Jan 2011

Cover And Contents

Turkish Journal of Zoology

No abstract provided.


Length-Weight Relationships Of Ten Fish Species From The Bulgarian Black Sea Waters, Maria Yankova, Danail Pavlov, Violin Raykov, Veselina Mihneva, Georghe Radu Jan 2011

Length-Weight Relationships Of Ten Fish Species From The Bulgarian Black Sea Waters, Maria Yankova, Danail Pavlov, Violin Raykov, Veselina Mihneva, Georghe Radu

Turkish Journal of Zoology

Length-weight relationships (LWRs) of 16,842 specimens of fish caught in the Bulgarian Black Sea waters, covering 9 families, 10 genera, and 10 species, were studied. Spiny dogfish (Squalus acanthias L.), thornback ray (Raja clavata L.), sprat (Sprattus sprattus L.), pontic shad (Alosa immaculata Eichwald), anchovy (Engraulis encrasicolus L.), whiting (Merlangius merlangus euxinus Pallas), horse mackerel (Trachurus mediterraneus Aleev), bonito (Sarda sarda Bloch), round goby (Neogobius melanostomus Pallas), and turbot (Psetta maxima L.) were collected from May 2006 to December 2008. The fishes were caught by different fishing techniques, such as gill net, trawl net, and trap nets. The slope or …


Biological Characteristics Of The Common Pandora, Pagellus Erythrinus (Linnaeus, 1758), In The Central Aegean Sea, Gülnur Meti̇n, Akin Türker İlkyaz, Ozan Soykan, Hasan Tuncay Kinacigi̇l Jan 2011

Biological Characteristics Of The Common Pandora, Pagellus Erythrinus (Linnaeus, 1758), In The Central Aegean Sea, Gülnur Meti̇n, Akin Türker İlkyaz, Ozan Soykan, Hasan Tuncay Kinacigi̇l

Turkish Journal of Zoology

We investigated the length distribution, sex ratio, sex inversion length, length-weight relationship, age, growth, spawning period, age and length at first maturity of the common pandora inhabiting İzmir Bay. A total of 2654 common pandora were collected by trawl hauls of İzmir Bay (Turkey) between January 2002 and June 2007. The size of the samples ranged from 4.1 cm (0.95 g, February) to 27.8 cm (207.30 g, April) in total length. The samples were composed of 64.7% females, 5.1% males, 0.3% hermaphrodites, and 29.9% immature individuals, with a female to male ratio of 1:0.08. The age composition of the samples …


Cover And Contents Jan 2011

Cover And Contents

Turkish Journal of Zoology

No abstract provided.


Some Small Mammal Fossils Of Üçağızlı Cave (Hatay, Turkey), Fadi̇me Suata Alpaslan Jan 2011

Some Small Mammal Fossils Of Üçağızlı Cave (Hatay, Turkey), Fadi̇me Suata Alpaslan

Turkish Journal of Zoology

Small mammal assemblages of Üçağızlı Cave, 2 from the early Upper Paleolithic and 1 from the Epipaleolithic, spanning a period from 41 to 17 kya, are described. The remains are referred to as Chionomys nivalis, Microtus guentheri, Apodemus mystacinus, Apodemus flavicollis, Apodemus witherbyi, Mus macedonicus, Mesocricetus brandti, Glirulus sp., Crocidura sp., Pipistrellus cf. kuhlii, and Myotis sp. The rodent fauna of Üçağızlı suggests the dominance of open country and rocky ground with a woodland component. There does not seem to have been any essential environmental changes during the deposition of these layers. However, the poor sample of the Epipaleolithic hampers …


Micropropagation Of The Apricot (Prunus Armeniaca L.) Cv. Hacıhaliloğlu By Means Of Single Node Culture, Hakan Yildirim, Ahmet Onay, Engi̇n Ti̇lkat, Zafer Aktürk Jan 2011

Micropropagation Of The Apricot (Prunus Armeniaca L.) Cv. Hacıhaliloğlu By Means Of Single Node Culture, Hakan Yildirim, Ahmet Onay, Engi̇n Ti̇lkat, Zafer Aktürk

Turkish Journal of Agriculture and Forestry

Hacıhaliloğlu is one of the most widely cultivated apricot (Prunus armeniaca L.) cultivars in Turkey. It produces fruit of excellent quality and is consumed both fresh and dried. In this study several factors affecting in vitro culture, rapid proliferation, rooting, and acclimatization of the apricot cultivar Hacıhaliloğlu were examined. During this study significant differences in harvesting dates were observed, with the month of May being noted as the best time to examine the in vitro culture of Hacıhaliloğlu. The effects of the cytokinin 6-benzylaminopurine (BA), kinetin (Kin), and thidiazuron (TDZ) were evaluated individually, and different concentrations of BA were also …