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Full-Text Articles in Physical Sciences and Mathematics

Kernel Operators On The Upper Half-Space: Boundedness And Compactness Criteria, Usman Ashraf, Muhammad Asif, Alexander Meskhi Jan 2014

Kernel Operators On The Upper Half-Space: Boundedness And Compactness Criteria, Usman Ashraf, Muhammad Asif, Alexander Meskhi

Turkish Journal of Mathematics

We establish necessary and sufficient conditions on a weight v governing the trace inequality \hat{K}f _{L^q_v(\hat{E})} \leq C f _{L^p(E)}, where E is a cone on a homogeneous group, \hat{E}: = E \times R_+ and \hat{K} is a positive kernel operator defined on \hat{E}. Compactness criteria for this operator are also established.


On Kakutani--Krein And Maeda--Ogasawara Spaces, Zafer Ercan, Neşet Özkan Tan Jan 2014

On Kakutani--Krein And Maeda--Ogasawara Spaces, Zafer Ercan, Neşet Özkan Tan

Turkish Journal of Mathematics

Let E be an Archimedean Riesz space. It is shown that the Kakutani--Krein space of the center of the Dedekind completion of E and the Maeda--Ogasawara space of E are homeomorphic. By applying this, we can reprove a Banach Stone type theorem for C^{\infty}(S) spaces, where S is a Stonean space.


A Characterization Of Certain Geodesic Hyperspheres In Complex Projective Space, Juan De Dios Perez, Y Oung Jin Suh Jan 2014

A Characterization Of Certain Geodesic Hyperspheres In Complex Projective Space, Juan De Dios Perez, Y Oung Jin Suh

Turkish Journal of Mathematics

We characterize geodesic hyperspheres of radius r such that cot^2(r)=\frac{1}{2} as the unique real hypersurfaces in complex projective space whose structure Jacobi operator satisfies a pair of conditions.


Adapted Basic Connections To A Certain Subfoliation On The Tangent Manifold Of A Finsler Space, Adelina Manea, Cristian Ida Jan 2014

Adapted Basic Connections To A Certain Subfoliation On The Tangent Manifold Of A Finsler Space, Adelina Manea, Cristian Ida

Turkish Journal of Mathematics

On the slit tangent manifold TM^0 of a Finsler space (M,F) there are given some natural foliations as vertical foliation and some other fundamental foliations produced by the vertical and horizontal Liouville vector fields, see [A. Bejancu, H. R. Farran, Finsler Geometry and Natural Foliations on the Tangent Bundle, Rep. Math. Physics 58, No. 1 (2006), 131--146]. In this paper we consider a (n,2n-1)-codimensional subfoliation (F_V,F_{\Gamma}) on TM^0 given by vertical foliation F_V and the line foliation spanned by vertical Liouville vector field \Gamma and we give a triplet of basic connections adapted to this subfoliation.


Characteristic Classes On Grassmannians, Jin Shi, Jianwei Zhou Jan 2014

Characteristic Classes On Grassmannians, Jin Shi, Jianwei Zhou

Turkish Journal of Mathematics

In this paper, we study the geometry and topology on the oriented Grassmann manifolds. In particular, we use characteristic classes and the Poincaré duality to study the homology groups of Grassmann manifolds. We show that for k=2 or n \leq 8, the cohomology groups H^*(G(k,n), R) are generated by the first Pontrjagin class, the Euler classes of the canonical vector bundles. In these cases, the Poincaré duality: H^q(G(k,n), R) \to H_{k(n-k)-q}(G(k,n), R) can be expressed explicitly.


Comparative Learning Global Particle Swarm Optimization For Optimal Distributed Generations' Output, Jasrul Jamani Jamian, Hazlie Mokhlis, Mohd Wazir Mustafa, Mohd Noor Abdullah, Muhammad Ariff Baharuddin Jan 2014

Comparative Learning Global Particle Swarm Optimization For Optimal Distributed Generations' Output, Jasrul Jamani Jamian, Hazlie Mokhlis, Mohd Wazir Mustafa, Mohd Noor Abdullah, Muhammad Ariff Baharuddin

Turkish Journal of Electrical Engineering and Computer Sciences

The appropriate output of distributed generation (DG) in a distribution network is important for maximizing the benefit of the DG installation in the network. Therefore, most researchers have concentrated on the optimization technique to compute the optimal DG value. In this paper, the comparative learning in global particle swarm optimization (CLGPSO) method is introduced. The implementation of individual cognitive and social acceleration coefficient values for each particle and a new fourth term in the velocity formula make the process of convergence faster. This new algorithm is tested on 6 standard mathematical test functions and a 33-bus distribution system. The performance …


Real-Time Control Of An Automated Guided Vehicle Using A Continuous Mode Of Sliding Mode Control, Bi̇rol Soysal Jan 2014

Real-Time Control Of An Automated Guided Vehicle Using A Continuous Mode Of Sliding Mode Control, Bi̇rol Soysal

Turkish Journal of Electrical Engineering and Computer Sciences

This paper proposes a tracking control method for a certain type of differential-drive wheeled mobile robot, called automated guided vehicles (AGVs), using a continuous mode approach of sliding mode control (SMC). The SMC applied produces a continuous signal in between the U and -U control signals instead of discrete ones. The controller is applied to control the velocity and direction angle of the vehicle in order to keep it on a desired path. The obtained algorithm is applied to the experimental system under load and disturbance to show its robustness. The experimental results are satisfactory and verify the performance of …


Solving A New Bi-Objective Joint Replenishment Inventory Model With Modified Rand And Genetic Algorithms, Ommolbanin Yousefi, Seyed Jafar Sadjadi Jan 2014

Solving A New Bi-Objective Joint Replenishment Inventory Model With Modified Rand And Genetic Algorithms, Ommolbanin Yousefi, Seyed Jafar Sadjadi

Turkish Journal of Electrical Engineering and Computer Sciences

There are many cases in real inventory systems where more than one objective must be optimized. The main purpose of this research is to develop a multiobjective joint replenishment problem (JRP), where one objective is the minimization of the total inventory investment and another is the minimization of the total inventory ordering and holding costs. To solve the suggested model, 3 algorithms are proposed. In the first algorithm, the existing RAND method, called the best heuristic for solving the JRP, is modified and a new heuristic algorithm is developed to be applicable to the JRP with 2 objectives. The second …


New Design Of Intelligent Load Shedding Algorithm Based On Critical Line Overloads To Reduce Network Cascading Failure Risks, Mehrdad Majidi, Mohammad-Reza Aghamohammadi, Moein Manbachi Jan 2014

New Design Of Intelligent Load Shedding Algorithm Based On Critical Line Overloads To Reduce Network Cascading Failure Risks, Mehrdad Majidi, Mohammad-Reza Aghamohammadi, Moein Manbachi

Turkish Journal of Electrical Engineering and Computer Sciences

This paper presents a new algorithm for intelligent load shedding based on critical line overloads. This method can increase the efficiency for determining critical lines and sensitive loads. Hence, when critical lines expose an overload, the system will run an intelligent load shedding, which considerably curtails the sensitive loads of critical transmission lines. This can fully reduce the harmful risks of power system cascading failures that impose extensive losses to the economy of a country. For testing the accuracy and applicability of this technique, the IEEE 39-bus test system is applied as a standard case study.


Face Recognition Across Pose Variation And The 3s Problem, Jamal Hussain Shah, Muhammad Sharif, Mudassar Raza, Aisha Azeem Jan 2014

Face Recognition Across Pose Variation And The 3s Problem, Jamal Hussain Shah, Muhammad Sharif, Mudassar Raza, Aisha Azeem

Turkish Journal of Electrical Engineering and Computer Sciences

Most face recognition methods are based on linear and nonlinear subspace features extraction and classification tasks. These classification methods are used for global and local facial features for person identification. Both local and global features play different roles for recognition and classification. There are a number of face recognition methods that have been proposed up until now, and they produce good results. However, when small sample size (3S) and pose variation problems are taken into consideration, face recognition becomes more complex and does not produce good results. In this paper, 3S and pose variation problems are dealt with. First, linear …


The Design Of An Embedded Spinal Cord Stimulator, Fi̇kret Yalçinkaya, Ali̇ Erbaş Jan 2014

The Design Of An Embedded Spinal Cord Stimulator, Fi̇kret Yalçinkaya, Ali̇ Erbaş

Turkish Journal of Electrical Engineering and Computer Sciences

Spinal cord stimulation is a physical therapy methodology utilizing electrical impulses, pulses, or a combination of various standard electrical waveforms to block pain. However, standard forms are not functioning effectively for each illness due to the unique conditions of the patient. Therefore, patient-specific waveforms (or user-defined waveforms) integrated with nondestructive, complete, or partially noninvasive and effective medical instruments to help relieve pain are required. In the literature, 2 different designs have been discussed: the bedside/portable and the implantable/surgical types. This work is introducing a new hybrid type: a portable touch-screen multichannel embedded spinal cord stimulator. This work is made of …


Multiuser Detection Using Soft Particle Swarm Optimization Along With Radial Basis Function, Muhammad Zubair, Muhammad Aamer Saleem Choudhry, Ijaz Mansoor Qureshi Jan 2014

Multiuser Detection Using Soft Particle Swarm Optimization Along With Radial Basis Function, Muhammad Zubair, Muhammad Aamer Saleem Choudhry, Ijaz Mansoor Qureshi

Turkish Journal of Electrical Engineering and Computer Sciences

The multiuser detection (MUD) problem was addressed as a pattern classification problem. Due to their strength in solving nonlinear separable problems, radial basis functions, aided by soft particle swarm optimization, were proposed to perform MUD for a synchronous direct sequence code division multiple access system. The proposed solution was shown to exhibit performance better than a number of other suboptimum detectors including the genetic algorithm and the classical particle swarm optimization algorithm.


Online Feature Selection And Classification With Incomplete Data, Habi̇l Kalkan Jan 2014

Online Feature Selection And Classification With Incomplete Data, Habi̇l Kalkan

Turkish Journal of Electrical Engineering and Computer Sciences

This paper presents a classification system in which learning, feature selection, and classification for incomplete data are simultaneously carried out in an online manner. Learning is conducted on a predefined model including the class-dependent mean vectors and correlation coefficients, which are obtained by incrementally processing the incoming observations with missing features. A nearest neighbor with a Gaussian mixture model, whose parameters are also estimated from the trained model, is used for classification. When a testing observation is received, the algorithm discards the missing attributes on the observation and ranks the available features by performing feature selection on the model that …


Deposition And Characterization Of Pbo--Pbs Multilayer Thin Films By Solution Growth Technique, Dominic Eya Jan 2014

Deposition And Characterization Of Pbo--Pbs Multilayer Thin Films By Solution Growth Technique, Dominic Eya

Turkish Journal of Physics

PbO-PbS thin films were deposited on glass substrates using the chemical bath deposition (CBD) technique. PbO thin films were deposited from the solution of lead nitrate (Pb(NO_3)_2) and sodium hydroxide (NaOH). Ethylenediaminetetraacetate (EDTA) served as the complexing agent. Some of the PbO films were used as substrate for the deposition of PbS. The PbS was deposited from alkaline solution of lead nitrate and thioacetamide. Triethanolamine was used as the complexing agent. Some of the films were subjected to thermal treatment after deposition. Energy dispersive X-ray fluorescence analysis confirmed the presence of Pb and S in the PbS thin films, while …


Quantum Chemical Calculations Of The Polymorphic Phase Transition Temperatures Of Zns, Znse, And Znte Crystals, Raşi̇t Ahiska, Dmytro Freik, Taras Parashchuk, Igor Gorichok Jan 2014

Quantum Chemical Calculations Of The Polymorphic Phase Transition Temperatures Of Zns, Znse, And Znte Crystals, Raşi̇t Ahiska, Dmytro Freik, Taras Parashchuk, Igor Gorichok

Turkish Journal of Physics

Molecular models of polymorphs modifications of zinc chalcogenides have been designed. Based on the results of ab initio quantum chemical calculations of the crystal structure of clusters the temperature dependences of the Gibbs energy of sphalerite and of wurtzite have been found. Phase transformations \"sphalerite-wurtzite\" temperatures have been evaluated.


Synthesis And Gas Sensor Applications Of Nanostructured Zno Grown At Low Temperatures, Oleg Lupan, Thierry Pauporte, Lee Chow Jan 2014

Synthesis And Gas Sensor Applications Of Nanostructured Zno Grown At Low Temperatures, Oleg Lupan, Thierry Pauporte, Lee Chow

Turkish Journal of Physics

ZnO nanoarchitecture-based nano- and microdevices came into the focus due to their multifunctional operation. In this work, we summarize cost-effective procedures to grow ZnO nano- and microstructures, namely hydrothermal growth and electrochemical deposition. These techniques allow the controllable growth of ZnO nano- and microarchitectures at relatively low temperatures, below 100 °C, and do not require sophisticated equipment. We report on technological details for synthesis of ZnO and its characterization and applications in different novel devices such as gas sensors. Nanosensors and microsensors were fabricated using a focused ion beam and by metal welding an individual nano- and microstructure to form …


Amorphous And Micromorph Si Solar Cells: Current Status And Outlook, Vitaliy Avrutin, Natalia Izyumskaya, Hadis Morkoç Jan 2014

Amorphous And Micromorph Si Solar Cells: Current Status And Outlook, Vitaliy Avrutin, Natalia Izyumskaya, Hadis Morkoç

Turkish Journal of Physics

An overview of the current status and prospects of thin-film Si photovoltaics, including both hydrogenated amorphous and microcrystalline Si as well their combination known as micromorph solar cells, with a major focus on the technological development is given. Although thin-film Si solar cells have been one of the first commercially successful photovoltaic devices, today they face a tremendous challenge from variety of bulk Si technologies (mono- and multicrystalline Si) and compound-semiconductor thin-film solar cells, both of which have managed to substantially reduce the production cost and improve power conversion efficiency. Thin-film Si photovoltaics benefiting from the mighty mainstream Si industry …


Electron Field Emission From Nanostructured Semiconductors Under Photo Illumination, Oktay Yilmazoglu, Anatoli Evtukh, Shihab Al-Daffaie, Jens-Peter Biethan, Dimitris Pavlidis, Vladimir Litovchenko, Hans L. Hartnagel Jan 2014

Electron Field Emission From Nanostructured Semiconductors Under Photo Illumination, Oktay Yilmazoglu, Anatoli Evtukh, Shihab Al-Daffaie, Jens-Peter Biethan, Dimitris Pavlidis, Vladimir Litovchenko, Hans L. Hartnagel

Turkish Journal of Physics

New device concepts and materials for the fabrication of compact high-frequency vacuum sources and micro-nano-integrated X-ray sources are of particular interest for broadband communication, security screening of packages and chemical materials, biomedical examination, and other applications. This article integrates results on GaN- and ZnO-based nano and self-assembled structures. They were used as field emitter tips for cold electron emission at high local electric fields as well as for photoassisted field emitters to generate bunched electrons directly from the emitter tip. The results on functional field emitters as cold electron sources will be presented. They are key elements for building, among …


Calixcephems: Clustered Cephalosporins Analogous To Calixpenams As Novel Potential Anti-Mrsa Agents, Fazel Nasuhi Pur, Karim Akbari Dilmaghani Jan 2014

Calixcephems: Clustered Cephalosporins Analogous To Calixpenams As Novel Potential Anti-Mrsa Agents, Fazel Nasuhi Pur, Karim Akbari Dilmaghani

Turkish Journal of Chemistry

Two novel clusters of cephalosporin based on calixarene were synthesized directly or by ring expansion of the penicillin arms of calixpenams to the corresponding cephem arms via sulfoxide intermediates. Antibiotic tests showed that calixcephems have a noteworthy increase in antibacterial activity against methicillin-resistant strains of Staphylococcus aureus (MRSA) with respect to parent calixpenams and their corresponding single cephems.


Geological, Petrological, And Geodynamical Characteristics Of The Karacaali Magmatic Complex (Kırıkkale) In The Central Anatolian Crystalline Complex, Turkey, Ömer Eli̇tok, Şenel Özdamar, Gürkan Bacak, Bektaş Uz Jan 2014

Geological, Petrological, And Geodynamical Characteristics Of The Karacaali Magmatic Complex (Kırıkkale) In The Central Anatolian Crystalline Complex, Turkey, Ömer Eli̇tok, Şenel Özdamar, Gürkan Bacak, Bektaş Uz

Turkish Journal of Earth Sciences

Mafic and felsic igneous rocks in the Karacaali Magmatic Complex (KMC) in the northwestern margin of the Central Anatolian Crystalline Complex (CACC) are classified into 4 groups: i) granitoid pluton including granite, granodiorite, and monzonite; ii) a few meter-scale porphyritic microgranite enclaves within the hybrid rocks; iii) hybrid rocks formed by mixing/mingling of mafic lavas (basaltic/diabasic/lamprophyric), anorthositic, and/or rhyolitic lavas; iv) diabasic dykes/veins within the granitoid pluton. Major element composition of the granitoid pluton and porphyritic microgranite enclaves within the hybrid rocks indicate subalkaline, calc-alkaline, and mostly I-type characteristics. These rocks are mainly peraluminous with aluminum saturation index > 1, but …


Nanosphere Lithography - Exploiting Self-Assembly On The Nanoscale For Sophisticated Nanostructure Fabrication, Eser Metin Akinoglu, Anthony John Morfa, Michael Giersig Jan 2014

Nanosphere Lithography - Exploiting Self-Assembly On The Nanoscale For Sophisticated Nanostructure Fabrication, Eser Metin Akinoglu, Anthony John Morfa, Michael Giersig

Turkish Journal of Physics

We demonstrate the fabrication of sophisticated nanostructures using nanosphere lithography (NSL). These include periodic triangular and pyramidal islands as well as periodically perforated thin films and cavities on the nano- and microscale. Furthermore, periodic arrays of vertically standing multiwalled carbon nanotubes are grown by plasma enhanced chemical vapor deposition from catalyst islands that were prepatterned by NSL. Moreover, we discuss the applicability of NSL to rough surfaces and show that the ratio between nanosphere size and roughness is determinant of the resulting nanostructure produced. Excellent, limited, and bad applicability of NSL are shown for smooth, rough, and very rough surfaces, …


Deriving The Snel-Descartes Law For A Single Photon, Randy Wayne Jan 2014

Deriving The Snel-Descartes Law For A Single Photon, Randy Wayne

Turkish Journal of Physics

The laws of reflection and refraction are typically derived using a dispersion relation that assumes that the angular frequency stays the same across a vacuum--dielectric interface and that the angular wave number increases. At the single photon level, this means that the total energy of the photon is conserved but the linear momentum is not. Here I derive the laws of reflection and refraction for a single photon using a dispersion relation that is consistent with the conservation of both total energy and linear momentum. To ensure that both conservation laws are upheld, the optical path length must be considered …


Synthesis Of New Pyrazole And Antibacterial Pyrazolopyrimidine Derivatives, Ameur Rahmouni, Anis Romdhane, Abderrahim Ben Said, Kaouther Majouli, Hichem Ben Jannet Jan 2014

Synthesis Of New Pyrazole And Antibacterial Pyrazolopyrimidine Derivatives, Ameur Rahmouni, Anis Romdhane, Abderrahim Ben Said, Kaouther Majouli, Hichem Ben Jannet

Turkish Journal of Chemistry

3-Substituted-1-phenyl-1H-pyrazolo[3,4-d]pyrimidin-4-amines 2a--c were synthesized by treating 5-aminopyrazole-4-carbonitriles 1a--c with formamide. The reactivity of compounds 1a--c towards some cyclic anhydrides was studied. The condensation of 5-aminopyrazole-4-carbonitrile 1b with triethylorthoformate gives imidate 7b, which reacts with a series of primary amines and leads to pyrazolo[3,4-d]pyrimidine-4-amines 9 and 10. The reaction of imidate 7b with ammonia and hydroxylamine afforded pyrazolopyrimidine 2b and pyrazolo[3,4-d]pyrimidin-5-(4H)-ol 11, respectively. The synthesized compounds were completely characterized by ^1H NMR, ^{13}C NMR, IR, and HRMS. The antibacterial activity of some new synthesized compounds was evaluated and appeared to be significant.


On A Tower Of Garcia And Stichtenoth, Seher Tutdere Jan 2014

On A Tower Of Garcia And Stichtenoth, Seher Tutdere

Turkish Journal of Mathematics

In 2003, Garcia and Stichtenoth constructed a recursive tower F = (F_n)_{n \geq 0} of algebraic function fields over the finite field F_q, where q = l^r with r \geq 1 and l > 2 is a power of the characteristic of F_q. They also gave a lower bound for the limit of this tower. In this paper, we compute the exact value of the genus of the algebraic function field F_n/F_q for each n \geq 0. Moreover, we prove that when q = 2^k, with k \geq 2, the limit of the tower F attains the lower bound given by …


Norden Structures Of Hessian Type, Arif Salimov, Aydin Gezer Jan 2014

Norden Structures Of Hessian Type, Arif Salimov, Aydin Gezer

Turkish Journal of Mathematics

In this paper, we show that Kähler (para-Kähler) manifolds admit a Norden--Hessian metric h = \nabla^2f if the function f is holomorphic (para-holomorphic), and we further consider the existence condition of para-Kähler structures for Norden--Hessian metrics.


Equivariant Structure Constants For Hamiltonian-T-Spaces, Ho Hon Leung Jan 2014

Equivariant Structure Constants For Hamiltonian-T-Spaces, Ho Hon Leung

Turkish Journal of Mathematics

If there exists a set of canonical classes on a compact Hamiltonian-T-space in the sense of R Goldin and S Tolman, we derive some formulas for certain equivariant structure constants in terms of other equivariant structure constants and the values of canonical classes restricted to some fixed points. These formulas can be regarded as a generalization of Tymoczko's results.


Moment Equalities For Sums Of Random Variables Via Integer Partitions And Faà Di Bruno's Formula, Dietmar Ferger Jan 2014

Moment Equalities For Sums Of Random Variables Via Integer Partitions And Faà Di Bruno's Formula, Dietmar Ferger

Turkish Journal of Mathematics

We give moment equalities for sums of independent and identically distributed random variables including, in particular, centered and specifically symmetric summands. Two different types of proofs, combinatorial and analytical, lead to 2 different types of formulas. Furthermore, the combinatorial method allows us to find the optimal lower and upper constants in the Marcinkiewicz--Zygmund inequalities in the case of even moment-orders. Our results are applied to give elementary proofs of the classical central limit theorem (CLT) and of the CLT for the empirical bootstrap. Moreover, we derive moment and exponential inequalities for self-normalized sums.


Effects Of A Current Transformer's Magnetizing Current On The Driving Voltage In Self-Oscillating Converters, Güngör Bal, Seli̇m Öncü Jan 2014

Effects Of A Current Transformer's Magnetizing Current On The Driving Voltage In Self-Oscillating Converters, Güngör Bal, Seli̇m Öncü

Turkish Journal of Electrical Engineering and Computer Sciences

Magnetizing inductance is one of the parameters that affect the phase and amplitude error of the output current of current transformers (CTs). In this study, the linear circuit model of a CT is developed to be used for driving purposes in power electronics applications. A simulation of the CT and its linear model is achieved. In the model circuit, the effect of the magnetizing inductance on the driving voltage can be examined. The equivalent circuit simulation results and the linear model simulation results along with the calculated results show agreement with each other. These results are compared with experimental results.


Passive Ac Network Supplying The Integration Of Ccc-Hvdc And Vsc-Hvdc Systems, Ali Bidadfar, Mehrdad Abedi, Mehdi Karrari, Gevorg .Babamalek Gharehpetian, Sanaz Namayan Tavana Jan 2014

Passive Ac Network Supplying The Integration Of Ccc-Hvdc And Vsc-Hvdc Systems, Ali Bidadfar, Mehrdad Abedi, Mehdi Karrari, Gevorg .Babamalek Gharehpetian, Sanaz Namayan Tavana

Turkish Journal of Electrical Engineering and Computer Sciences

The integration of a capacitor-commutated converter (CCC) high-voltage direct current (HVDC) (CCC-HVDC) and voltage source converter (VSC) HVDC (VSC-HVDC) is proposed in this paper to supply entirely passive AC networks. The key point of this integration is the flat characteristic of the DC voltage of the CCC-HVDC, which provides the condition for the VSC to connect to the CCC DC link via a current regulator. The advantages of the proposed combined infeeding system are the requirement of only one DC line, and better dynamic responses. The structure of the proposed infeeding system, as well as its control system, is studied. …


Design, Optimization, And Realization Of A Wire Antenna With A 25:1 Bandwidth Ratio For Terrestrial Communications, Korkut Yeği̇n Jan 2014

Design, Optimization, And Realization Of A Wire Antenna With A 25:1 Bandwidth Ratio For Terrestrial Communications, Korkut Yeği̇n

Turkish Journal of Electrical Engineering and Computer Sciences

Wire antennas can be made wideband if the antenna is loaded with passive elements and connected to a lossless matching network. However, realization of the load component values and matching network can easily become impractical. In this study, using only a surface mount and standard component values, antenna loads and a matching network are optimized using genetic algorithms. The optimized design achieves a 25:1 bandwidth ratio, from 20 MHz to 500 MHz, with a maximum voltage standing wave ratio (VSWR) of 3.5 and minimum system gain of --5 dBi. The antenna system gain at azimuth is taken as the objective …