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Full-Text Articles in Physical Sciences and Mathematics

A Simple Formula Obtained Using Tabu Search Algorithm For The Radiation Efficiency Of A Resonant Rectangular Microstrip Antenna, Dervi̇ş Karaboğa, Keri̇m Güney Jan 1999

A Simple Formula Obtained Using Tabu Search Algorithm For The Radiation Efficiency Of A Resonant Rectangular Microstrip Antenna, Dervi̇ş Karaboğa, Keri̇m Güney

Turkish Journal of Electrical Engineering and Computer Sciences

A new simple formula for the radiation efficiency of a resonant rectangular microstrip patch antenna is presented. The formula is obtained by using a tabu search algorithm, which is a quite new optimization technique based on the principles of intelligent problem solving. The formula is valid for substrates with relative permittivities between 1 and 12.8 and for the complete range of thicknesses normally used. The results obtained by using this new simple formula are in conformity with those reported elsewhere. The formula can also be used in the calculation of the radiation efficiency of dipoles.


A Fake Cusp And A Fishtail, Selman Akbulut Jan 1999

A Fake Cusp And A Fishtail, Selman Akbulut

Turkish Journal of Mathematics

No abstract provided.


Canonical Framings For 3 -Manifolds, Rob Kirby, Paul Melvin Jan 1999

Canonical Framings For 3 -Manifolds, Rob Kirby, Paul Melvin

Turkish Journal of Mathematics

No abstract provided.


Univalent Harmonic Mappings Onto Half Planes, Meti̇n Öztürk Jan 1999

Univalent Harmonic Mappings Onto Half Planes, Meti̇n Öztürk

Turkish Journal of Mathematics

We consider the class S_H(D,\Omega ) of complex functions f which are univalent, harmonic, sense preserving on a simple connected domain D\neq {\Bbb C} \ containing the origin, satisfy f(0)=a_0, f_{\bar z}(0)=0a,\ a\in {\Bbb R}\}. In particularly, we describe the closure \overline{S_H(D,\Omega )} of S_H(D,\Omega ) and characterize its extreme points, as well as sharp estimates for coefficients and distortion theorems.


Augmented Noetherian Graded Modules, Mashhoor Refai̇ Jan 1999

Augmented Noetherian Graded Modules, Mashhoor Refai̇

Turkish Journal of Mathematics

Let $G$ be a multiplicative group with identity $e$, and let $R$ be an associative $G$-graded ring with unity 1. In this paper we study the augmented graded Noetherian modules and try to give some relationships between the Noetherian modules in the category $R-Agr$ and the Noetherian modules in the category $R_e-gr$.


The Isometries Of The Bochner Space L^P(\Mu,H), Bahatti̇n Cengi̇z Jan 1999

The Isometries Of The Bochner Space L^P(\Mu,H), Bahatti̇n Cengi̇z

Turkish Journal of Mathematics

In this article, the known characterization of the surjective linear isometries of the Bochner space $L^p(\mu, H)$, for a $\sigma$-finite measure $\mu$ and an arbitrary Hilbert space $H$, in terms of regular set isomorphisms of the $\sigma$-algebra involved and strongly measurable families of surjective isometries of $H$, is extended to arbitrary measures.


Two Lemmas On Formal Power Series, Kazim İlhan İkeda, Masatoshi İkeda Jan 1999

Two Lemmas On Formal Power Series, Kazim İlhan İkeda, Masatoshi İkeda

Turkish Journal of Mathematics

Let $L$ be a local field and $\tilde{L}$ the completion of the maximal unramified extension of $L$. In this short note, we prove \noindent (I) the sequences \noindent (1$^{\prime\prime}$) $0\rightarrow {\cal O}_L$[[$X_1,\ldots,X_n$]]$\rightarrow{\cal O}_{\tilde{L}}$[[$X_1,\ldots,X_n$]] $\stackrel{\phi_L-1}{\ra}{\cal O}_{\tilde{L}}$[[$X_1,\ldots,X_n$]]$\rightarrow 0$ \noindent and \noindent (2$^{\prime\prime}$) $1\rightarrow {\cal O}_L$[[$X_1,\ldots,X_n$]]$^x\rightarrow{\cal O}_{\tilde{L}}$[[$X_1,\ldots,X_n$]] $^x\stackrel{\phi_L-1}{\ra}{\cal O}_{\tilde{L}}$[[$X_1,\ldots,X_n$]]$\rightarrow 1$ \noindent are exact, where $\theta_L$ is the Frobenius automorphism over $L$ applied on the coefficients of ${\cal O}_{\tilde{L}}$[[$X_1,\ldots, X_n$]], and $\theta_L-1$ respectively denotes the mapping $\alpha\mapsto\alpha^{\theta L}-\alpha$ for \noindent (1$^{\prime\prime}$) and $\epsilon\mapsto\frac{\epsilon^{\phi}L}{\epsilon}$ for (2$^{\prime\prime}$); \noindent (II) ${\cal C}^{\circ}(\tilde{L},h)$ being the group the Coleman power series of degree 0, the sequence $$ 1\rightarrow {\cal …


Seiberg-Witten Invariants Of Mapping Tori,Symplectic Fixed Points, And Lefschetz Numbers, Dietmar A. Salamon Jan 1999

Seiberg-Witten Invariants Of Mapping Tori,Symplectic Fixed Points, And Lefschetz Numbers, Dietmar A. Salamon

Turkish Journal of Mathematics

No abstract provided.


Virtual Neighborhoods And Pseudo-Holomorphic Curves, Yongbin Ruan Jan 1999

Virtual Neighborhoods And Pseudo-Holomorphic Curves, Yongbin Ruan

Turkish Journal of Mathematics

No abstract provided.


Countable Dense Homogeneous Bıtopologıcal Spaces, Abdalla Tallafha, Adnan Al-Bsoul, Ali̇ Ahmad Fora Jan 1999

Countable Dense Homogeneous Bıtopologıcal Spaces, Abdalla Tallafha, Adnan Al-Bsoul, Ali̇ Ahmad Fora

Turkish Journal of Mathematics

In this paper we shall introduce the concept of being countable dense homogeneous bitopological spaces and define several kinds of this concept. We shall give some results concerning these bitopological spaces and their relations. Also, we shall prove that all of these bitopological spaces satisfying the axioms p-T_0 and p-T_1.


A Stone's Representation Theorem And Some Applications, Eissa D. Habil Jan 1999

A Stone's Representation Theorem And Some Applications, Eissa D. Habil

Turkish Journal of Mathematics

In this paper, we prove the following form of Stone's representation theorem: Let \sum be a \sigma-algebra of subsets of a set X. Then there exists a totally disconnected compact Hausdorff space {\cal K} for which (\sum, \cup, \cap) and ({\cal C}({\cal K}), \cup ,\cap), where {\cal C}({\cal K}) denotes the set of all clopen subsets of {\cal K}, are isomorphic as Boolean algebras. Furthermore, by defining appropriate joins and meets of countable families in {\cal C}({\cal K}), we show that such an isomorphism preserves \sigma-completeness. Then, as a consequence of this result, we obtain the result that if ba(X,\sum) …


Tyurina Components And Rational Cycles For Rational Singularities, Meral Tosun Jan 1999

Tyurina Components And Rational Cycles For Rational Singularities, Meral Tosun

Turkish Journal of Mathematics

In this paper, we give a geometric proof of Pinkham's theorem on the positive cycles supported on the exceptional divisor of a rational singularity. In order to do this, we give several properties of the Tyurina components of the exceptional divisor and of the points of blowing-up surface of a rational singularity.


A Survey On Drinfeld Modular Forms, Ernst-Ulrich Gekeler Jan 1999

A Survey On Drinfeld Modular Forms, Ernst-Ulrich Gekeler

Turkish Journal of Mathematics

No abstract provided.


On The Global Stabilization Of Nonlinear Systems Via Switching Manifolds, Stephen P. Banks, Meti̇n U. Salamci, M. Kemal Özgören Jan 1999

On The Global Stabilization Of Nonlinear Systems Via Switching Manifolds, Stephen P. Banks, Meti̇n U. Salamci, M. Kemal Özgören

Turkish Journal of Electrical Engineering and Computer Sciences

The global stabilization of nonlinear systems is investigated by using switching surfaces. The nonlinear system is forced to a lower order switching manifold, which is designed to be stable by construction. Thus, the stability of the reduced-order system is guaranteed and parameter selection for the switching surface is avoided. The method is extended to a class of uncertain nonlinear systems and exemplified with some fictitious dynamic models.


Effects Of Parasitic Elements On Oscillation Frequency Of Ota-C Sinusoidal Oscillators, Ari̇f Nacaroğlu, Ergun Erçelebi̇ Jan 1999

Effects Of Parasitic Elements On Oscillation Frequency Of Ota-C Sinusoidal Oscillators, Ari̇f Nacaroğlu, Ergun Erçelebi̇

Turkish Journal of Electrical Engineering and Computer Sciences

An oscillator circuit which incorporates Operational Transconductance Amplifiers is presented. The circuit is designed using three OTAs and two grounded capacitors. The frequency of oscillation is tunable over a wide frequency range. The effects of the parasitic elements on the oscillation frequency and the oscillation condition are studied. The theoretical results are compared with the experimental results for a practical oscillator circuit.


Differentiating Type Of Muscle Movement Via Ar Modeling And Neural Network Classification, Beki̇r Karlik Jan 1999

Differentiating Type Of Muscle Movement Via Ar Modeling And Neural Network Classification, Beki̇r Karlik

Turkish Journal of Electrical Engineering and Computer Sciences

The aim of this study is to classify electromyogram (EMG) signals for controlling multifunction proshetic devices. An artificial neural network (ANN) implementation was used for this purpose. Autoregressive (AR) parameters of $a_1, a_2, a_3, a_4$ and their signal power obtained from different arm muscle motions were applied to the input of ANN, which is a multilayer perceptron. At the output layer, for 5000 iterations, six movements were distinguished at a high accuracy of 97.6%.


The Norm In Taxicab Geometry, Cumali̇ Eki̇ci̇, I. Kocayusufoğlu, Z. Akça Jan 1998

The Norm In Taxicab Geometry, Cumali̇ Eki̇ci̇, I. Kocayusufoğlu, Z. Akça

Turkish Journal of Mathematics

In this paper, we will define the inner-product and the norm in taxicab geometry and then we will discuss this inner-product geometrically.


The Dual Of The Bochner Space L^P(\Mu,E) For Arbitrary \Mu, Bahatti̇n Cengi̇z Jan 1998

The Dual Of The Bochner Space L^P(\Mu,E) For Arbitrary \Mu, Bahatti̇n Cengi̇z

Turkish Journal of Mathematics

Let $\mu$ be a finite measure, $E$ a Banach space, and $1\leq p


On A Certain Subclass Of Analytic Functions With Negative Cefficients, M. K. Aouf, Nak Eun Cho Jan 1998

On A Certain Subclass Of Analytic Functions With Negative Cefficients, M. K. Aouf, Nak Eun Cho

Turkish Journal of Mathematics

The object of the present paper is to derive several interesting properties of the class $T_n\lam$ consisting of analytic and univalent functions with negative coefficients. Coefficient inequalities, distortion theorems and closure theorems of functions in the class $T_n\lam$ are determined. Also radii of close-to-convexity, starlikeness and convexity are determined. Furthermore, integral operators and modified Hadamard products of several functions belonging to the class $Tn\lam$ are studied here.


The Non Uniform Bounds Of Remainder Term In Clt For The Sum Of Functions Of Uniform Spacings, S. Mirakhmedov, U. Kalandarov Jan 1998

The Non Uniform Bounds Of Remainder Term In Clt For The Sum Of Functions Of Uniform Spacings, S. Mirakhmedov, U. Kalandarov

Turkish Journal of Mathematics

The non uniform bound of the remainder in the central limit theorem for the sums of functions of uniform spacings is established. The bound depend on the moments of functions of the standard exponential random variables.


Petrogenesis Of The Çiçekdağ Igneous Complex, N Of Kırşehir, Centralanatolia, Turkey, Sabah Yilmaz Şahi̇n, Durmuş Boztuğ Jan 1998

Petrogenesis Of The Çiçekdağ Igneous Complex, N Of Kırşehir, Centralanatolia, Turkey, Sabah Yilmaz Şahi̇n, Durmuş Boztuğ

Turkish Journal of Earth Sciences

Central Anatolia typically represents well-preserved geological features of a collision zone. This collision zone is characterized by some geological events occurred in the Anatolide passive margin of the Anatolide-Pontide collision along the Ankara Erzincan suture zone. This suture zone is commonly known to be formed by the pre-Maastrichtian northward subduction of the northern branch of Neo-Tethys beneath the Pontides which was constituting the southernmost tip of Eurasiain plate at that time. These geological occurrences are inverted metamorphism; ophiolitic slabs derived from main suture zone; syn-collisional and S/C ST type magmatism; post-collisional, high-K calcalkaline, hybrid and I/H LO type magmatism; post-collisional, …


Evidence For Damaging Historical Earthquakes At Priene, Western Turkey, Erhan Altunel Jan 1998

Evidence For Damaging Historical Earthquakes At Priene, Western Turkey, Erhan Altunel

Turkish Journal of Earth Sciences

The ancient cilty of Priene was one of the earliest Ionian settlements within the western part of the Büyük Menderes valley (the ancient Maeander River) and was first founded about 8 km in the east of the present site. The old Priene was probably destroyed by a destructive earthquake in the 350s BC and the city was shifted to the existing place in 350 BC. The new city contains an abundance of evidence related to earthquakes. The following evidence indicates that damaging earthquakes, occurred in the Büyük Menderes graben, caused great damage to the new Priene. (1) Part of the …


Petrology Of The Post-Collisional, Within-Plate Yıldızdağ Gabbroic Pluton, Yıldızeli-Sivas Region, Central Anatolia, Turkey, Durmuş Boztuğ, Mustafa Yağmur, Nazmi Otlu, Sibel Tatar, Akif Yeşi̇ltaş Jan 1998

Petrology Of The Post-Collisional, Within-Plate Yıldızdağ Gabbroic Pluton, Yıldızeli-Sivas Region, Central Anatolia, Turkey, Durmuş Boztuğ, Mustafa Yağmur, Nazmi Otlu, Sibel Tatar, Akif Yeşi̇ltaş

Turkish Journal of Earth Sciences

The Yildizdag gabbroic pluton intrudes the Paleocene-Eocene Yakupoğlan formation which is imbricated with the ophiolitic melange of the northern branch of the Neo-Tethyan ocean, and the crustal metasediments of Kırsehir block or Central Anatolian Crystalline Complex. It is subdivided into some mapable subunits such as gabbroic main body, dioritic marginal facies and microdioritic dykes. Mineralogical-geochemical (major, some trace and REE) data reveal that the magnetite + olivine + augite + calcic plagioclase, and hornblende + biotite + intermediate (or sodic) plagioclase fractionation/accumulation has formed the gabbroic main body and dioritic rocks, respectively, during the solidification of a single mafic magma …


Geochemistry And Origin Of The Oligocene Binkılıç Manganese Deposit;Thrace Basin, Turkey, Ali Haydar Gülteki̇n Jan 1998

Geochemistry And Origin Of The Oligocene Binkılıç Manganese Deposit;Thrace Basin, Turkey, Ali Haydar Gülteki̇n

Turkish Journal of Earth Sciences

Many Oligocene Manganese deposits are found in the Trace basin, a Tertiary collisional-collapse type basin in the northwestern part of Turkey. All the mineralizations are originally sedimentary type. The most economically important deposits are around Çatalça; of these, the Binkılıç manganese ore occurs conformably within the Oligocene fossiliferous formations, as a stratiform type manganese deposit. The manganese ores at Binkiliç show a continuity along strike and consists of micro-to Cryptocrystalline pyrolusite, psilomelane, radial manganite, cryptomelane, wad, rhodochrosite and dispersed organic matter, calcite, feldspar, clay minerals, and quartz but generally only minor quantities of limonite and goethite. Mn oxides with variable …


The Origin Of Clay Minerals In Salina Playa-Mudflat Facies,Yeniçubuk Formation (Lower-Middle Miocene), Gemerek, Sivas, Türkiye, İbrahim Türkmen, Cemal Bölücek Jan 1998

The Origin Of Clay Minerals In Salina Playa-Mudflat Facies,Yeniçubuk Formation (Lower-Middle Miocene), Gemerek, Sivas, Türkiye, İbrahim Türkmen, Cemal Bölücek

Turkish Journal of Earth Sciences

The playa-mudflat facies under investigation are found in the Gemerek Basin (Sivas, Türkiye). This Miocene basin is bordered by the Akdağ Metamorphics (Paleozoic) to the N-NW, the Elmalıdağ Volcanic Rocks (Thanetian) to the E and clastic rocks and evaporites of the Cevizcik Formation (Oligocene) to the S-SW. Illite, palygorskite, smectites (montmorillonite, saponite and sauconite), chlorite (clinochlore) and serpentines had been studied using XRD analysis of mudstone samples. Illites and chlorites were found to have originated from marble, schists, granitic rocks, dioritic rocks and syenitic rocks of Akdağ Massif to the north. Palygorskite were formed in evaporitic basins by chemical sedimantation. …


Dimensionality And Energy Levels Of Quantum Mechanical Systems, Harry A. Mavromatis Jan 1998

Dimensionality And Energy Levels Of Quantum Mechanical Systems, Harry A. Mavromatis

Turkish Journal of Physics

The $N$-dimensional Schrödinger equation involving a general, central potential $V_N(r)$, is decomposed into a 3-dimensional component plus a term that may be treated as a dimension-dependent perturbation. This allows discussion of the general $N$-dimensional system from a 3-dimensional perspective.


Structural Defects And Electrical Properties Of Extruded Samples Of Bi_{85}Sb_{15} Solid Solutions, Farkhad Samedov, Mail Tagiev Jan 1998

Structural Defects And Electrical Properties Of Extruded Samples Of Bi_{85}Sb_{15} Solid Solutions, Farkhad Samedov, Mail Tagiev

Turkish Journal of Physics

The effect of 5 hours annealing in vacuum $\sim 10^{-3} Pa$ at $503 K$ on the electroconductivity $(\sigma)$, the coefficient of thermoelectric power $(\alpha)$ and the Hall coefficient $(R_x)$ for extruded samples of $Bi_{85}Sb_{15}$ has been investigated in the temperature range from $\sim 77 K$ up to $\sim 300 K$. The samples were taken with a different concentration of $Pb$ (lead) up to $\sim 0.1 a.w \%$. The anisotropy of electrical properties of these samples was also studied in the temperature range between $77 K$ and $300 K$ and in the presence of magnetic field up to $\sim 74 \times …


Theoretical Analysis Of The Crystallography For Do_3 --> M18r Martensitic Transformation, Seyfettin Çakmak, Ekrem Artunç Jan 1998

Theoretical Analysis Of The Crystallography For Do_3 --> M18r Martensitic Transformation, Seyfettin Çakmak, Ekrem Artunç

Turkish Journal of Physics

A mathematical approach of the phenomenological theory has been applied to the martensitic transformation of DO$_3 \rightarrow$ M18R close-packed structure. The crystallography of DO$_3 \rightarrow$ M18R martensitic transformation in Fe-25.8 wt\%Mn-7.4wt\%Al-0.11wt\%C alloy was studied using single crystals. Martensitic crystallographic parameters such as habit plane, magnitude of lattice invariant shear, shape deformation direction and orientation relationships are calculated with new mathematical approach. Phenomenological theoretical calculations were compared with predictions of the phenomenological crystallographic CRAB theory and with experimental observations.


Effect Of Neutron Irradiation On Carriers Removel Rates In N-Si, M.S. Yunusov, M. Karimov, B.L. Oksengendler, M.A. Zhalelov Jan 1998

Effect Of Neutron Irradiation On Carriers Removel Rates In N-Si, M.S. Yunusov, M. Karimov, B.L. Oksengendler, M.A. Zhalelov

Turkish Journal of Physics

Carrier removal rate in $n-Si \langle P, Rh \rangle$ with different doping rhodium concentrations were investigated under fast neutrons irradiation. It is shown that the rate of carrier removal increases with phosphorus atom concentration but decreases with rhodium atom concentration. Theoretical analysis on the base of kinetic equations has shown that standard scheme of quasichemical reactions taking into account the interaction between rhodium atoms, vacancies and self interstitial atoms could not explain the results of experiment. Therefore a new model based on the use of radiation to increase the barrier between regions of fluctuating impurity concentration has been proposed.


An Analysis Of The Variation In Calculated Confined-State Energies Using Different Envelope-Function Models, Beşire Gönül Jan 1998

An Analysis Of The Variation In Calculated Confined-State Energies Using Different Envelope-Function Models, Beşire Gönül

Turkish Journal of Physics

We investigate different formulations of the envelope-function method and show that the accuracy of the calculated zone-centre confinement energies can be calculated by means of bulk band structure. We show how coupling to the conduction and spin-split-off bands can decrease the light-hole zone-centre confinement energies and lead to significant differences in the calculated subband dispersion.