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Mohr-Circle-Based Rotational Invariants Of A Magnetotelluric Data Set From The Thrace Region Of Turkey: Geological Implications, Murat Bayrak, Aysan Gürer, Ö. Feyzi̇ Gürer, O. Meti̇n İlkişik, Ahmet T. Başokur Jan 2006

Mohr-Circle-Based Rotational Invariants Of A Magnetotelluric Data Set From The Thrace Region Of Turkey: Geological Implications, Murat Bayrak, Aysan Gürer, Ö. Feyzi̇ Gürer, O. Meti̇n İlkişik, Ahmet T. Başokur

Turkish Journal of Earth Sciences

In the summer of 1995, magnetotelluric data were acquired at forty sites along a southwest-northeast profile crossing northwestern Turkey in continental Europe. The traverse, 204 km in length, crossed the boundary between a metamorphic mass called the Istranca Massif and a large Tertiary sedimentary basin called the Thrace Basin. The pseudosections of Mohr-circle-based rotational invariant characteristics of the magnetotelluric data such as central impedance (d3), anisotropy angle (l) and phase of central impedance (fd3) were prepared with classical magnetotelluric parameters (apparent resistivity and impedance phase), and detailed Mohr-circle displays were shown for selected stations as a function of the Bostick …


Comment On “Petrography And Petrology Of The Calc-Alkaline Sarıhan Granitoid (Ne Turkey): An Example Of Magma Mingling And Mixing”, Gülteki̇n Topuz, Aral İ. Okay Jan 2006

Comment On “Petrography And Petrology Of The Calc-Alkaline Sarıhan Granitoid (Ne Turkey): An Example Of Magma Mingling And Mixing”, Gülteki̇n Topuz, Aral İ. Okay

Turkish Journal of Earth Sciences

No abstract provided.


A Fractal Example Of A Continuous Monotone Function With Vanishing Derivatives On A Dense Set And Infinite Derivatives On Another Dense Set, Bünyami̇n Demi̇r, Vakif Dzhafarov, Şahi̇n Koçak, Mehmet Üreyen Jan 2006

A Fractal Example Of A Continuous Monotone Function With Vanishing Derivatives On A Dense Set And Infinite Derivatives On Another Dense Set, Bünyami̇n Demi̇r, Vakif Dzhafarov, Şahi̇n Koçak, Mehmet Üreyen

Turkish Journal of Mathematics

Inspired by the theory of analysis on fractals, we construct an example of a continuous, monotone function on an interval, which has vanishing derivatives on a dense set and infinite derivatives on another dense set. Although such examples could be constructed by classical means of probability and measure theory, this one is more elementary and emerges naturally as a byproduct of some new fractal constructions.


Second-Order Nonlinear Three Point Boundary-Value Problems On Time Scales, S. Gülşan Topal Jan 2006

Second-Order Nonlinear Three Point Boundary-Value Problems On Time Scales, S. Gülşan Topal

Turkish Journal of Mathematics

We consider a second order three point boundary value problem for dynamic equations on time scales and establish criteria for the existence of at least two positive solutions of an eigenvalue problem by an application of a fixed point theorem in cones. Existence result for non-eigenvalue problem is also given by the monotone method.


Existence Of Periodic Solutions For Second Order Rayleigh Equations With Piecewise Constant Argument, Gen-Qiang Wang, Sui Sun Cheng Jan 2006

Existence Of Periodic Solutions For Second Order Rayleigh Equations With Piecewise Constant Argument, Gen-Qiang Wang, Sui Sun Cheng

Turkish Journal of Mathematics

Based on a continuation theorem of Mawhin, periodic solutions are found for the second-order Rayleigh equation with piecewise constant argument.


A Connected Sum Of Knots And Fintushel-Stern Knot Surgery On 4-Manifolds, Manabu Akaho Jan 2006

A Connected Sum Of Knots And Fintushel-Stern Knot Surgery On 4-Manifolds, Manabu Akaho

Turkish Journal of Mathematics

We give some new examples of smooth 4-manifolds which are diffeomorphic although they are obtained by Fintushel-Stern knot surgeries on a smooth 4-manifold with different knots; the first such examples are given by Akbulut [1]. In the proof we essentially use the monodromy of a cusp.


On Cauchy's Bound For Zeros Of A Polynomial, V. K. Jain Jan 2006

On Cauchy's Bound For Zeros Of A Polynomial, V. K. Jain

Turkish Journal of Mathematics

In this note, we improve upon Cauchy's classical bound, and upon some recent bounds for the moduli of the zeros of a polynomial.


Computational Sciences: At The Intersection Of Science And Engineering--Case Study For Academic And Research Programs, Menas Kafatos, Peter Becker, Zafer Boybeyi̇ Jan 2006

Computational Sciences: At The Intersection Of Science And Engineering--Case Study For Academic And Research Programs, Menas Kafatos, Peter Becker, Zafer Boybeyi̇

Turkish Journal of Electrical Engineering and Computer Sciences

No abstract provided.


Infusing Technical Communication And Teamwork Within The Ece Curriculum, By April Kedrowicz, Sundy Watanabe, Damon Hall, Cynthia Furse Jan 2006

Infusing Technical Communication And Teamwork Within The Ece Curriculum, By April Kedrowicz, Sundy Watanabe, Damon Hall, Cynthia Furse

Turkish Journal of Electrical Engineering and Computer Sciences

This paper highlights a unique approach to infusing formal training and practice in oral and written communication and teamwork development in the Department of Electrical and Computer Engineering (ECE) at the University of Utah. Faculty and graduate (Ph.D.) students from the College of Humanities have teamed up with faculty from engineering to develop communication and teamwork instruction that is integrated into the existing engineering curriculum. These skills are used as a vehicle to provide better understanding of engineering concepts and their applications.


Introducing Students To Communications Concepts Using Optical And Low-Power Wireless Devices, James M. Conrad, Ivan Howitt Jan 2006

Introducing Students To Communications Concepts Using Optical And Low-Power Wireless Devices, James M. Conrad, Ivan Howitt

Turkish Journal of Electrical Engineering and Computer Sciences

Wireless communication has become an important feature for commercial products and a popular research topic within the last ten years. There are now more mobile phone subscriptions than wired-line subscriptions. Lately, one area of commercial interest has been low-cost, low-power, and short-distance wireless communication used for "personal wireless networks." Technology advancements are providing smaller and more cost effective devices for integrating computational processing, wireless communication, and a host of other functionalities. These embedded communications devices will be integrated into applications ranging from homeland security to industry automation and monitoring. They will also enable custom tailored engineering solutions, creating a revolutionary …


Readjusting The Current Trend In Electrical Power Engineering, Johan Smit, Peter Morshuis, Edward Gulski Jan 2006

Readjusting The Current Trend In Electrical Power Engineering, Johan Smit, Peter Morshuis, Edward Gulski

Turkish Journal of Electrical Engineering and Computer Sciences

In this paper the electrical power education curriculum is analyzed from the viewpoint of the electrical power industry and from the viewpoint of young people that contemplate their future academic study. From the perspective of young people in industrialized countries contemplating their future and the possibilities of an academic study, the current curriculum in (power) engineering lacks attraction. The number of freshmen still shows a decreasing trend. This paper is aimed to be a contribution towards readjusting this trend


Complex Analysis Of The Lossy-Transmission Line Theory: A Generalized Smith Chart, E. Gago-Ribas, C. Dehesa-Martinez, M. J. Gonzalez-Morales Jan 2006

Complex Analysis Of The Lossy-Transmission Line Theory: A Generalized Smith Chart, E. Gago-Ribas, C. Dehesa-Martinez, M. J. Gonzalez-Morales

Turkish Journal of Electrical Engineering and Computer Sciences

It has been very usual in the specialized literature to skip the detailed study of the lossy transmission line theory by reducing it to the low-loss approximation. Although this is valid in the most common practical cases, the study of the general lossy case becomes very important due to the fact that it makes possible a better and deeper understanding of the physical effects associated to general losses, as well as the low-loss frequency-dependent regime. Besides, the analysis of the general case provides important results that may be extended to the analysis of real waveguiding systems, facilitating the understanding and …


Secure Digital Communication Using Chaotic Symbolic Dynamics, Ajeesh P. Kurian, Sadasivan Puthusserypady Jan 2006

Secure Digital Communication Using Chaotic Symbolic Dynamics, Ajeesh P. Kurian, Sadasivan Puthusserypady

Turkish Journal of Electrical Engineering and Computer Sciences

One of the major hurdles in implementing chaotic communication schemes is the synchronization of chaotic systems. For the last two decades, numerous contributions of varying successes have been made by researchers from different disciplines for the synchronization of chaotic systems. Symbolic dynamics based synchronization method is shown to be capable of providing high quality synchronization (HQS), which is essential for reliable communication. In this work, using this method, a secure digital communication system is proposed. The well known piece-wise linear 1-D map such as tent map and Bernoulli shift map are used for this study. Since the information is dynamically …


A Corpus-Based Concatenative Speech Synthesis System For Turkish, Haşi̇m Sak, Tunga Güngör, Yaşar Safkan Jan 2006

A Corpus-Based Concatenative Speech Synthesis System For Turkish, Haşi̇m Sak, Tunga Güngör, Yaşar Safkan

Turkish Journal of Electrical Engineering and Computer Sciences

Speech synthesis is the process of converting written text into machine-generated synthetic speech. Concatenative speech synthesis systems form utterances by concatenating pre-recorded speech units. Corpus-based methods use a large inventory to select the units to be concatenated. In this paper, we design and develop an intelligible and natural sounding corpus-based concatenative speech synthesis system for the Turkish language. The implemented system contains a front-end comprised of text analysis, phonetic analysis, and optional use of transplanted prosody. The unit selection algorithm is based on commonly used Viterbi decoding algorithm of the best-path in the network of the speech units using spectral …


Speech Pre-Processing For Pitch And Pitch-Cylce Evolutions Smoothing, Hassan Farsi Jan 2006

Speech Pre-Processing For Pitch And Pitch-Cylce Evolutions Smoothing, Hassan Farsi

Turkish Journal of Electrical Engineering and Computer Sciences

In low bit rate speech coders, pitch is usually transmitted once per frame and, when needed, the intermediate pitch values are obtained by interpolation between 2 adjacent pitch values. Although pitch usually evolves slowly, sometimes it has irregular variations and the estimated pitch differs from the real one. In addition, some speech coders, e.g., waveform interpolation coders, rely on smooth pitch-cycle evolutions to extract speech model parameters in the analysis stage. However, non-stationary characteristics of speech may lead to inaccurate estimation of the parameters. This affects the synthesised speech quality. We propose a pre-processor, which modifies the residual speech signal …


A Pi Controller Based On Gain-Scheduling For Synchronous Generator, Alireza Sedaghati Jan 2006

A Pi Controller Based On Gain-Scheduling For Synchronous Generator, Alireza Sedaghati

Turkish Journal of Electrical Engineering and Computer Sciences

In this paper a gain- scheduling scheme of a proportional integral (GSPI) controller is proposed for a synchronous generator. In presented scheme, both proportional and integral gains are allowed to vary within a predetermined range. In order to validate the effectiveness of GSPI controller, simulation studies for a single-machine infinite bus power system are used .The results verify improved performance of GSPI controller comparing to conventional AVR under various operating conditions.


Adaptive 3d Visual Servo Control Of Robot Manipulators Via Composite Camera Inputs, Türker Şahi̇n, Erkan Zergeroğlu Jan 2006

Adaptive 3d Visual Servo Control Of Robot Manipulators Via Composite Camera Inputs, Türker Şahi̇n, Erkan Zergeroğlu

Turkish Journal of Electrical Engineering and Computer Sciences

This paper considers the problem of position control of robot manipulators via visual servoing in the presence of uncertainty associated with the robot dynamics and the vision system. Specifically, an adaptive controller is designed to compensate for the uncertainties associated with the mechanical parameters of the robot manipulator and the intrinsic parameters of the cameras. The 3D visual information is obtained from the composite inputs of two separate cameras placed in the robot work space. Despite the uncertainties associated with the camera system and robot dynamics the proposed adaptive controller achieves asymptotic end effector position tracking. A Lyapunov based approach …


Human Identification Using Gait, Murat Eki̇nci̇ Jan 2006

Human Identification Using Gait, Murat Eki̇nci̇

Turkish Journal of Electrical Engineering and Computer Sciences

Gait refers to the style of walking of an individual. This paper presents a view-invariant approach for human identification at a distance, using gait recognition. Recognition of a person from their gait is a biometric of increasing interest. Based on principal component analysis (PCA), this paper describes a simple, but efficient approach to gait recognition. Binarized silhouettes of a motion object are represented by 1-D signals, which are the basic image features called distance vectors. The distance vectors are differences between the bounding box and silhouette, and are extracted using 4 projections of the silhouette. Based on normalized correlation of …


Sturm-Liouville Equation: The Bridge Between Eigenvalue And Green's Function Problems, Levent Sevgi̇ Jan 2006

Sturm-Liouville Equation: The Bridge Between Eigenvalue And Green's Function Problems, Levent Sevgi̇

Turkish Journal of Electrical Engineering and Computer Sciences

This article is intended as an educational aid and discusses guided wave propagation problems that are modeled via the Sturm-Liouville equation in electromagnetics. The bridge between source-free (eigenvalue) and source-driven (Green's function) problems that are represented by the same Sturm-Liouville equation is emphasized. The presentation focuses on representation of an arbitrary source from the features (eigenfunctions) of the problem geometry and extraction of the eigenvalues of a problem from propagation characteristics (Green's function) on a canonical problem; a homogeneously filled parallel plate waveguide with non-penetrable boundaries


Agents For Integrating Distributed Data For Complex Computations, Ahmed M. Khedr, Raj Bhatnagar Jan 2006

Agents For Integrating Distributed Data For Complex Computations, Ahmed M. Khedr, Raj Bhatnagar

Turkish Journal of Electrical Engineering and Computer Sciences

Algorithms for many complex computations assume that all the relevant data are available on a single node of a computer network. In the emerging distributed and networked knowledge environments, databases relevant for computations may reside on a number of nodes connected by a communication network. These data resources cannot be moved to other network sites due to privacy, security, and size considerations. The desired global computation must be decomposed into local computations to match the distribution of data across the network. The capability to decompose computations must be general enough to handle different distributions of data and different participating nodes …


An Ann Based Approach To Improve The Distance Relaying Algorithm, Hassan Khorashadi Zadeh, Zuyi Li Jan 2006

An Ann Based Approach To Improve The Distance Relaying Algorithm, Hassan Khorashadi Zadeh, Zuyi Li

Turkish Journal of Electrical Engineering and Computer Sciences

This paper presents an artificial neural network- (ANN) based approach to improve the performance of the distance relaying algorithm. The proposed distance relay uses magnitudes of voltages and currents as input signals to find fault locations. In this approach, an ANN has been included in the protection algorithm as an extension of the existing methods, which improves the reliability of the protection operation. The design procedure of the proposed relay is presented in detail. Simulation studies are performed and the influence of changing system parameters, such as fault resistance and source impedance, is studied. Performance studies show that the proposed …


Finite Groups All Of Whose Abelian Subgroups Of Equal Order Are Conjugate, Sezgi̇n Sezer, Robert W. Van Der Waall Jan 2006

Finite Groups All Of Whose Abelian Subgroups Of Equal Order Are Conjugate, Sezgi̇n Sezer, Robert W. Van Der Waall

Turkish Journal of Mathematics

In this paper we classify the finite groups whose abelian subgroups of equal order (B^*-groups) are conjugate. The classification has been achieved by means of a lot of general structure properties of B^*-groups, provided in the course of the paper.


On Certain Modified Meyer-König And Zeller Operators, Lucyna Rempulska, Karolina Tomczak Jan 2006

On Certain Modified Meyer-König And Zeller Operators, Lucyna Rempulska, Karolina Tomczak

Turkish Journal of Mathematics

We introduce certain modified Meyer-König and Zeller operators and we study their approximation properties. The similar results for modified Bernstein polynomials were given in [6].


On Lifts Of Paracomplex Structures, Mehmet Tekkoyun Jan 2006

On Lifts Of Paracomplex Structures, Mehmet Tekkoyun

Turkish Journal of Mathematics

In this paper, we obtain vertical, complete and horizontal lifts of paracomplex geometric structures on paracomplex manifolds to its tangent bundle. Also, we obtain integrability on paracomplex tangent bundle.


Decompositions Of Continuity, Talal Al-Hawary, Ahmad Al-Omari Jan 2006

Decompositions Of Continuity, Talal Al-Hawary, Ahmad Al-Omari

Turkish Journal of Mathematics

In 2004, Al-Hawary and Al-Omari introduced and explored the class of \omega^o-open sets which is strictly stronger than the class of \omega-open sets and weaker than that of open sets. In this paper, we introduce what we call \omega^o-continuity and \omega_X^o-continuity and we give several characterizations and two decompositions of \omega ^o-continuity. Finally, new decompositions of continuity are provided.


Connectedness In Isotonic Spaces, Eissa D. Habil, Khalid A. Elzenati Jan 2006

Connectedness In Isotonic Spaces, Eissa D. Habil, Khalid A. Elzenati

Turkish Journal of Mathematics

An isotonic space (X,cl) is a set X with isotonic operator cl:P(X) \to P(X) which satisfies cl(\emptyset) = \emptyset and cl(A)\subseteq cl(B) whenever A\subseteq B\subseteq X. Many properties which hold in topological spaces hold in isotonic spaces as well. The notion of connectedness that is familiar from topological spaces generalizes to isotonic spaces. We further extend the notions of Z-connectedness and strong connectedness to isotonic spaces, and we indicate the intimate relationship between these notions.


The Restriction And The Continuity Properties Of Potentials Depending On \Lambda-Distance, M. Zeki̇ Sarikaya, Hüseyi̇n Yildirim Jan 2006

The Restriction And The Continuity Properties Of Potentials Depending On \Lambda-Distance, M. Zeki̇ Sarikaya, Hüseyi̇n Yildirim

Turkish Journal of Mathematics

In this study we establish theorems on the restriction and continuity of the generalized Riesz potentials with the non-isotropic kernels depending on \lambda-distance.


On Reduced And Semicommutative Modules, Muhi̇tti̇n Başer, Nazim Agayev Jan 2006

On Reduced And Semicommutative Modules, Muhi̇tti̇n Başer, Nazim Agayev

Turkish Journal of Mathematics

In this paper, various results of reduced and semicommutative rings are extended to reduced and semicommutative modules. In particular, we show: (1) For a principally quasi-Baer module, M_R is semicommutative if and only if M_R is reduced. (2) If M_R is a p.p.-module then M_R is nonsingular.


Two-Weight Norm Inequalities For Some Anisotropic Sublinear Operators, Yusuf Zeren, V. S. Guliyev Jan 2006

Two-Weight Norm Inequalities For Some Anisotropic Sublinear Operators, Yusuf Zeren, V. S. Guliyev

Turkish Journal of Mathematics

In this paper, we establish several general theorems for the boundedness of the anisotropic sublinear operators on a weighted Lebesgue space. Conditions of these theorems are satisfied by many important operators in analysis. We also give some applications the boundedness of the parabolic singular integral operators, and the maximal operators associated with them from one weighted Lebesgue space to another one. Using this results, we prove weighted embedding theorems for the anisotropic Sobolev spaces W_{\omega_0,\omega_1,...,\omega_n}^{l_1,...,l_n}(\Rn).


On Graded Weakly Prime Ideals, Shahabaddin Ebrahimi Atani Jan 2006

On Graded Weakly Prime Ideals, Shahabaddin Ebrahimi Atani

Turkish Journal of Mathematics

Let G be an arbitrary group with identity e, and let R be a G-graded commutative ring. Weakly prime ideals in a commutative ring with non-zero identity have been introduced and studied in [1]. Here we study the graded weakly prime ideals of a G-graded commutative ring. A number of results concerning graded weakly prime ideals are given. For example, we give some characterizations of graded weakly prime ideals and their homogeneous components.