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Power Quality Enhancement In Hybrid Pv-Bes System Based On Ann-Mppt, Heli̇n Bozkurt, Özgür Çeli̇k, Ahmet Teke Sep 2024

Power Quality Enhancement In Hybrid Pv-Bes System Based On Ann-Mppt, Heli̇n Bozkurt, Özgür Çeli̇k, Ahmet Teke

Turkish Journal of Electrical Engineering and Computer Sciences

Battery energy systems (BESs) assisted photovoltaic (PV) plants are among the popular hybrid power systems in terms of energy efficiency, energy management, uninterrupted power supply, grid-connected and off-grid availability. The primary objective of this study is to enhance the power quality of a grid-tied PV-BES hybrid system by developing an operation strategy based on Artificial Neural Network (ANN) based maximum power point tracking (MPPT) method. A test system comprising a 10-kWh BES and a 12.4 kW PV plant is structured and simulated on the MATLAB/Simulink platform. The hybrid system is validated with three different cases: constant radiation, rapid changing radiation, …


A Single Operational Amplifier-Based Grounded Meminductor Mutators And Their Applications, Shalini Gupta, Kunwar Singh, Shireesh Kumar Rai Sep 2024

A Single Operational Amplifier-Based Grounded Meminductor Mutators And Their Applications, Shalini Gupta, Kunwar Singh, Shireesh Kumar Rai

Turkish Journal of Electrical Engineering and Computer Sciences

In this work, three simple configurations of meminductor mutator are presented. The first two configurations of meminductor mutator have been implemented utilizing one CMOS-based operational amplifier, one memristor, one capacitor, and five resistors, while the third configuration of meminductor mutator is implemented utilizing one CMOS based operational amplifier, two memristors, one capacitor, and four resistors. The implementation and simulation of the proposed configurations are done by using LTspice tool. The viability of the proposed circuits is demonstrated by utilizing TSMC 180 nm CMOS technology parameters. The proposed circuits of the meminductor have a simple structure in contrast to many of …


Cover And Contents Sep 2024

Cover And Contents

Turkish Journal of Electrical Engineering and Computer Sciences

No abstract provided.


Mention Detection In Turkish Coreference Resolution, Şeni̇z Demi̇r, Hani̇fi̇ İbrahi̇m Akdağ Sep 2024

Mention Detection In Turkish Coreference Resolution, Şeni̇z Demi̇r, Hani̇fi̇ İbrahi̇m Akdağ

Turkish Journal of Electrical Engineering and Computer Sciences

A crucial step in understanding natural language is detecting mentions that refer to real-world entities in a text and correctly identifying their boundaries. Mention detection is commonly considered a preprocessing step in coreference resolution which is shown to be helpful in several language processing applications such as machine translation and text summarization. Despite recent efforts on Turkish coreference resolution, no standalone neural solution to mention detection has been proposed yet. In this article, we present two models designed for detecting Turkish mentions by using feed-forward neural networks. Both models extract all spans up to a fixed length from input text …


Finger Movement Recognition Using Machine Learning Algorithms With Tree-Seed Algorithm, Muhammed Sami̇ Karakul, Ahmet Gökçen Sep 2024

Finger Movement Recognition Using Machine Learning Algorithms With Tree-Seed Algorithm, Muhammed Sami̇ Karakul, Ahmet Gökçen

Turkish Journal of Electrical Engineering and Computer Sciences

Electromyography (EMG) signals have been used to recognize various actions of hand movements, finger movements, and hand gestures. This paper aims to improve the classification accuracy of EMG signals while decreasing the number of features using the Tree-Seed Algorithm. The dataset containing EMG signals utilized in this investigation is derived from a publicly accessible source. The rationale for selecting the Tree-Seed Algorithm centers on its ability to enhance classification accuracy while minimizing the dimensionality of feature sets. The object function and Tree-Seed Algorithm's nature avoids the results to have low accuracy with fewer features. The aim is not just to …


Enhancing Dtc Control Of Im Using Fuzzy Logic And Three-Level Inverter: A Comparative Study, Siham Mencou, Majid Benyakhlef, Elbachir Tazi Sep 2024

Enhancing Dtc Control Of Im Using Fuzzy Logic And Three-Level Inverter: A Comparative Study, Siham Mencou, Majid Benyakhlef, Elbachir Tazi

Turkish Journal of Electrical Engineering and Computer Sciences

Direct torque control is the most appropriate strategy for induction motor drive systems, due to its considerable ability to reduce the impact of of machine parameter variations, while offering fast dynamic response and simplified control implementation. However, persistent problems associated with high torque ripple and variable switching frequencies prevent its widespread adoption. To overcome these limitations, several techniques have been developed, in particular the use of multi-level inverters and fuzzy logic algorithms. This article proposes an in-depth evaluation of these techniques in a MATALB/Simulink environment, under various operational conditions. The main objective is to provide a detailed performance analysis of …


The Heat Kernel On A Finite Graph In Different Time-Scales, Yang Chen, Jay Jorgenson, Luis Lopez, Lejla Smajlovic Sep 2024

The Heat Kernel On A Finite Graph In Different Time-Scales, Yang Chen, Jay Jorgenson, Luis Lopez, Lejla Smajlovic

Turkish Journal of Mathematics

Let G be a finite, weighted graph, and let [[EQUATION]] be a Time-scale with a fixed point [[EQUATION]] such that sup[[EQUATION]]. In this paper we construct the heat kernel on G in Time-scale [[EQUATION]] in terms of a certain convolution series involving he heat operator acting on a parametrix, which is a fairly general function depending on the vertex set of G and the time variable [[EQUATION]]. We develop some applications by choosing different parametrices and various Time-scales. The results we obtain here do extend, in part, aspects of the recent articles in that the Time-scale considered in this paper …


Φ−Pluriharmonicity And Φ−Invariance Of Pointwise Bislant Riemanniansubmersions, Grayson Light, Cem Sayar, Mehmet Aki̇f Akyol Sep 2024

Φ−Pluriharmonicity And Φ−Invariance Of Pointwise Bislant Riemanniansubmersions, Grayson Light, Cem Sayar, Mehmet Aki̇f Akyol

Turkish Journal of Mathematics

In this research, we investigate the intriguing realm of pointwise bislant Riemannian submersions, a generalizationof many previous submersions, such as antiinvariant, slant, semislant, pointwise slant, pointwise semislant,and bislant submersions, within the framework of almost product manifolds. After giving an original example, wedelve into the submersion’s integrability conditions and geodesics. We explore the concept of φ−pluriharmonicity andφ−invariance within this context. The study sheds light on the profound interplay between pointwise bislant submersions’fibers and their being either geodesic or mixed geodesic, offering valuable insights into these intriguing mappings’geometric properties.


Ideals In Semigroups Of Partial Transformations With Invariant Set, Jitsupa Srisawat, Yanisa Chaiya Sep 2024

Ideals In Semigroups Of Partial Transformations With Invariant Set, Jitsupa Srisawat, Yanisa Chaiya

Turkish Journal of Mathematics

This paper explores the ideals and their structural properties in two generalizations of the partial transformationsemigroup. Furthermore, principal, maximal, and minimal ideals within these semigroups are elucidated.


Transmission Eigenvalues Problem Of A Schrödinger Equation, Emel Yildirim, Elgiz Bairamov Sep 2024

Transmission Eigenvalues Problem Of A Schrödinger Equation, Emel Yildirim, Elgiz Bairamov

Turkish Journal of Mathematics

In this paper, transmission eigenvalues of a Schrödinger equation have been studied by constructing a new inner product and using Weyl theory. Necessary conditions for these eigenvalues to be negative, real and finite have been examined. This method has provided a new framework related to transmission eigenvalue problems and investigation of their properties. The conclusions has been verified for special case of the problem.


Comprehensive Computational Study On Transient Heat Transfer In Functionally Graded Longitudinal Fins Under Time-Varying Laser Heating, Hüseyi̇n Demi̇r, İnci̇ Çi̇li̇ngi̇r Süngü, İbrahi̇m Keleş Sep 2024

Comprehensive Computational Study On Transient Heat Transfer In Functionally Graded Longitudinal Fins Under Time-Varying Laser Heating, Hüseyi̇n Demi̇r, İnci̇ Çi̇li̇ngi̇r Süngü, İbrahi̇m Keleş

Turkish Journal of Mathematics

The present study assumes that the material properties of the fin vary by a force rule in the axial direction, with the exception of the thermal relaxation coefficient, which is assumed to be constant. The temperature distribution in the longitudinal fin with homogeneous cross-section exposed to the laser heat source is numerically investigated. This is because these constraints lead to a linear differential equation with partial solutions that can't be analytically resolved using conventional methods, except for a few elementary order functions. Consequently, a linear or non-linear system of equations as a function of time is obtained by transforming a …


A Short Note On Generalized Robertson Walker Spacetimes, Uday Chand De, Aydin Gezer Sep 2024

A Short Note On Generalized Robertson Walker Spacetimes, Uday Chand De, Aydin Gezer

Turkish Journal of Mathematics

In this article, generalized Robertson Walker spacetimes are investigated in light of perfect fluid spacetimes. First, we establish that a perfect fluid spacetime with non-vanishing vorticity whose associated scalars are constant along the velocity vector field becomes a generalized Robertson Walker spacetime. Among others, it is also shown that a Ricci parallel perfect fluid spacetime is either a generalized Robertson Walker spacetime or a static spacetime. Finally, we acquire that in a conformally semi-symmetric generalized Robertson Walker spacetime of dimension $4$, the scalar curvature vanishes and the spacetime is locally isometric to the Minkowski spacetime, provided the electric part of …


Individual Stability Of Representations Of Abelian Semigroups, Heybetkulu Mustafayev Sep 2024

Individual Stability Of Representations Of Abelian Semigroups, Heybetkulu Mustafayev

Turkish Journal of Mathematics

Let S be a suitable subsemigroup of a locally compact abelian group and let T={T(s)}s(-S be a bounded and strongly continuous trepresentation of S on a Banach space X. In this note, we study the spectral conditions on T and the ergodic conditios on x in X which will imply that T(s)x-->0 strongly as s--> infinity through S.


A Non-Newtonian Conics In Multiplicative Analytic Geometry, Aykut Has, Beyhan Yilmaz Sep 2024

A Non-Newtonian Conics In Multiplicative Analytic Geometry, Aykut Has, Beyhan Yilmaz

Turkish Journal of Mathematics

In this study, conics (circle, ellipse, hyperbola) are characterized by taking into account basic multiplicationoperations in multiplicative space. For this purpose, firstly multiplicative axes and regions are introduced. Additionally,the multiplicative cone definition is given and visualized on the figure. General definitions and theorems of non-Newtonianconics are given. Additionally, examples were given and drawings were made to make the resulting characterizations andtheorems more memorable.


On The Connection Between Σϵ(A1 ⊗ A2) And Σϵ(A1), Σϵ(A2) For Certain Specialoperators, Fati̇h Yilmaz Sep 2024

On The Connection Between Σϵ(A1 ⊗ A2) And Σϵ(A1), Σϵ(A2) For Certain Specialoperators, Fati̇h Yilmaz

Turkish Journal of Mathematics

In this paper, the connection between the ϵ -pseudospectrum of the tensor product operator A1 ⊗ A2 andthe ϵ -pseudospectrums of operators A1 and A2 has been investigated and some results are given about this connectionunder certain conditions.


Rings And Finite Fields Whose Elements Are Sums Or Differences Of Tripotents And Potents, Adel Abyzov, Stephen Cohen, Peter Danchev, Daniel Tapkin Sep 2024

Rings And Finite Fields Whose Elements Are Sums Or Differences Of Tripotents And Potents, Adel Abyzov, Stephen Cohen, Peter Danchev, Daniel Tapkin

Turkish Journal of Mathematics

We significantly strengthen results on the structure of matrix rings over finite fields and applythem to describe the structure of the so-called weakly n-torsion clean rings. Specifically, we establish that, forany field F with either exactly seven or strictly more than nine elements, each matrix over F is presentableas a sum of of a tripotent matrix and a q-potent matrix if and only if each element in F is presentable as asum of a tripotent and a q-potent, whenever q > 1 is an odd integer. In addition, if Q is a power of an oddprime and F is a field …


Spherical Product Hypersurfaces In Euclidean Spaces, Sezgi̇n Büyükkütük, Günay Öztürk Sep 2024

Spherical Product Hypersurfaces In Euclidean Spaces, Sezgi̇n Büyükkütük, Günay Öztürk

Turkish Journal of Mathematics

Spherical product surfaces are obtained with the help of a special product by considering two curves inn−dimensional space. One of their special cases is rotational surface. The reason why the present study is significantthat the spherical product is used to construct hypersurfaces. (n−1)−curves are needed during this construction. Firstly,the spherical product hypersurfaces are defined in E4 , Gaussian and mean curvature are yielded and then conditionsbeing flat or minimal are examined. Moreover, superquadrics, which are associated with spherical product, are handledfor the first time in hypersurface form and give some examples. Finally, spherical product hypersurfaces are generalizedto n−dimensional Euclidean space …


A Sufficient Condition For The Wildness Of An Automorphism Of A Free Leibnizalgebra, Zeynep Özkurt Sep 2024

A Sufficient Condition For The Wildness Of An Automorphism Of A Free Leibnizalgebra, Zeynep Özkurt

Turkish Journal of Mathematics

In this paper, we apply the criterion of Mikhalev and Umirbaev for the invertibility of an endomorphismof a finitely generated free Leibniz algebra via its Jacobian matrix to determine whether a given endomorphism is anautomorphism. Moreover, it is shown that the invertibility of the determinant of the Jacobian matrix of an automorphismimplies its wildness.


A Note On The Hull And Linear Complementary Pair Of Cyclic Codes, Zohreh Aliabadi, Tekgül Kalayci Sep 2024

A Note On The Hull And Linear Complementary Pair Of Cyclic Codes, Zohreh Aliabadi, Tekgül Kalayci

Turkish Journal of Mathematics

The Euclidean hull of a linear code C is defined as C ∩ C⊥ , where C⊥ denotes the dual of C underthe Euclidean inner product. A linear code with the trivial hull is called a linear complementary dual (LCD) code. Apair (C,D) of linear codes of length n over the finite field Fq is called a linear complementary pair (LCP) of codes ifC ⊕ D = Fnq. More generally, a pair (C,D) of linear codes of the same length over Fq is called a linear ℓ -intersectionpair of codes if C ∩D has dimension ℓ as a vector space …


Cover And Contents Sep 2024

Cover And Contents

Turkish Journal of Mathematics

No abstract provided.


Cover And Contents Sep 2024

Cover And Contents

Turkish Journal of Zoology

No abstract provided.


Biosorption Of Ni (Ii), Pb (Ii) And Cu (Ii) Metal Ions On The Chitin Isolated From Spider Species Of Drassodes Lapidosus, Albulene Emini, Osman Seyyar, Yavuz Sürme Sep 2024

Biosorption Of Ni (Ii), Pb (Ii) And Cu (Ii) Metal Ions On The Chitin Isolated From Spider Species Of Drassodes Lapidosus, Albulene Emini, Osman Seyyar, Yavuz Sürme

Turkish Journal of Zoology

This study evaluates the biosorption ability of chitin derived from a specific spider species namely Drassodes lapidosus (Walckenaer, 1802) belongs to Gnaphosidae family. The obtained chitin was characterized by fourier transform infrared spectroscopy (FT-IR), thermogravimetric analysis (TGA), X-ray diffraction (XRD), and scanning electron microscopy (SEM) analysis. In the alpha form of the obtained chitin, its thermal stability was observed to be 356.9 ℃ and, the Crl value was 69.16%. In addition, this chitin was used as a bioadsorbent to remove heavy metal ions such as Ni (II), Cu (II) and Pb (II) from the aqueous medium by solid phase extraction …


Summer Daily Activity Patterns Of Mountain Rock Lizards Of The Balkan Peninsula (Dinarolacerta Spp.), Katarina Ljubisavljević, Nataša Tomašević Kolarov, Aleksandar Urošević, Lidija Leković, Snežana Vuksanović, Tanja D. Vukov Sep 2024

Summer Daily Activity Patterns Of Mountain Rock Lizards Of The Balkan Peninsula (Dinarolacerta Spp.), Katarina Ljubisavljević, Nataša Tomašević Kolarov, Aleksandar Urošević, Lidija Leković, Snežana Vuksanović, Tanja D. Vukov

Turkish Journal of Zoology

We studied the daily activity patterns of Dinarolacerta rock lizards, endemic to the Dinaric mountains of the Western Balkans, during the summer season. The study was conducted in Montenegro at four sites for D. mosorensis and three sites for D. montenegrina. The air temperature at which the lizards were observed varied significantly both within and between species and decreased with altitude, while the temperature of the rocky ground was more stable and higher than air temperature at each study site. Males and females of both species displayed similar activity patterns, while immatures tended to be active at the time when …


Green Turtle Nesting Activity On Yeniyurt Beach, Hatay, Türkiye: Six-Year Results (2017–2022), Bektaş Sönmez Sep 2024

Green Turtle Nesting Activity On Yeniyurt Beach, Hatay, Türkiye: Six-Year Results (2017–2022), Bektaş Sönmez

Turkish Journal of Zoology

Conducting long-term conservation and monitoring activities for sea turtles provides a more precise depiction of their population status compared to studies conducted across a single year. The frequency of the nesting activity may fluctuate dramatically over time, depending on the environmental conditions. This study aimed to examine the nest count, female abundance, and reproductive output of green turtles on Yeniyurt beach in the eastern Mediterranean between 2017 and 2022. The beach was surveyed annual monitoring at consistent intervals. Temporal variations in the number of nests and the abundance of females were analyzed using the Mann-Kendall and Sen Slope tests. A …


Effects Of Microplastics On Aquatic Organisms: A Comprehensive Review, Sedat Gündoğdu, İrem Nur Yeşi̇lyurt, Zohaib Abbas, Makbule Baylan Sep 2024

Effects Of Microplastics On Aquatic Organisms: A Comprehensive Review, Sedat Gündoğdu, İrem Nur Yeşi̇lyurt, Zohaib Abbas, Makbule Baylan

Turkish Journal of Zoology

Microplastics (MPs) are pervasive pollutants that pose significant threats to marine ecosystems. This review examines the impact of MPs on marine organisms, highlighting key areas of concern and knowledge gaps.The aim of this paper is to synthesize recent findings on the occurrence and biological impacts of MPs in marine environments. For this purpose a total of 171 studies conducted in different geographical regions were examined in order to ascertain the interaction of numerous vertebrate and invertebrate taxonomic groups with microplastic. Based on this analysis the pathways through which MPs enter marine ecosystems and their interactions with marine organisms were examined. …


Study Of Avian Migration Patterns Using Stable Isotope Analysis In The Galite Archipelago, Tunisia, Hsan Ben Jemaa, Said Nouira, François Fourel, Ilham Bentaleb Sep 2024

Study Of Avian Migration Patterns Using Stable Isotope Analysis In The Galite Archipelago, Tunisia, Hsan Ben Jemaa, Said Nouira, François Fourel, Ilham Bentaleb

Turkish Journal of Zoology

This research employed stable isotope analysis to investigate the migratory patterns and geographic origins of the Eleonora's falcon (Falco eleonorae) and its associated prey species within the Galite Archipelago, Tunisia. Feathers collected from both juvenile and adult falcons, along with their prey, were analysed for deuterium isotopic composition using the "Isorix" package in R, which facilitated the geographic assignment based on stable isotope ratios. The results demonstrated no significant difference in deuterium values (δ2H) between adult and juvenile falcons, indicating a lack of geographical variation in moulting locations among the different age groups. However, the isotopic data for adult falcons …


Morphometric And Meristic Differentiation Among Five Populations Of Delminichthys Ghetaldii (Actinopterygii, Cyprinidae) From Five Karst Fields In Eastern Herzegovina, Dušanka Berak Čihorić, Ana Marić, Danilo Mrdak, Predrag Simonović Sep 2024

Morphometric And Meristic Differentiation Among Five Populations Of Delminichthys Ghetaldii (Actinopterygii, Cyprinidae) From Five Karst Fields In Eastern Herzegovina, Dušanka Berak Čihorić, Ana Marić, Danilo Mrdak, Predrag Simonović

Turkish Journal of Zoology

The primary objectives of this study were to advance our understanding of the morphological intricacies exhibited by the endemic fish species, Delminichthys ghetaldii, commonly known as the Trebinje minnow, and to determine intraspecific morphological variability. The study involved the examination of 76 mature specimens collected from five distinct karst fields located within the Dinaric region of Eastern Herzegovina, Bosnia and Herzegovina, since the year 2018. A comprehensive analysis of 22 morphometric and 8 meristic characters was conducted to unravel the underlying patterns of variation. Discriminant Function Analysis was employed for the thorough investigation of morphometric traits, whereas Canonical Correspondence Analysis …


Dietary Observations Of Adult Pleurodema Nebulosum (Anura: Leptodactylidae) From Argentina, Gabriel Natalio Castillo, Cynthia J. González- Rivas Sep 2024

Dietary Observations Of Adult Pleurodema Nebulosum (Anura: Leptodactylidae) From Argentina, Gabriel Natalio Castillo, Cynthia J. González- Rivas

Turkish Journal of Zoology

This study is the first to examine the diet composition of adult Pleurodema nebulosum specimens based on an analysis of the gastrointestinal contents of 78 individuals. Analyzed herein were 40 specimens from a site disturbed due to anthropogenic action and 38 from a protected area in Argentina. Differences were found in the trophic consumption at both sites. In the protected area, P. nebulosum presented an active foraging mode, with a diet specialized in prey items from the Formicidae family. At the disturbed site, this amphibian showed a sit-and-wait foraging mode, with a generalist diet where it consumes Hemiptera and Coleoptera. …


Investigation Of The Status Of Immune Checkpoint Molecules (Pd-L1 And Pd-1) In Meningiomas By Immunohistochemistry, İsmai̇l Saygin, Emel Çakir, Seher Nazli Kazaz, Ali̇ Riza Güverci̇n, İlker Eyüpoğlu, Müşerref Müge Ustaoğlu Aug 2024

Investigation Of The Status Of Immune Checkpoint Molecules (Pd-L1 And Pd-1) In Meningiomas By Immunohistochemistry, İsmai̇l Saygin, Emel Çakir, Seher Nazli Kazaz, Ali̇ Riza Güverci̇n, İlker Eyüpoğlu, Müşerref Müge Ustaoğlu

Turkish Journal of Medical Sciences

Background/aim : Meningiomas are the most common primary brain tumors of the central nervous system. Immunotherapy is a promising treatment method applied in many types of cancer. There is no standard and effective medical treatment to reduce recurrence and mortality in cases of incomplete resection of meningiomas and in high-grade cases. In order to investigate medical treatments in addition to surgery and radiotherapy, in this study, the status of immune checkpoint molecules (PD-L1/PD-1), which are the target of immunotherapy, in meningiomas was investigated.Materials and Methods: Four hundred two cases of meningioma diagnosed between 2007 and 2020 in our institution were …


Targeted Temperature Management In Obstetrics For Prevention Perinatal Encephalopathy, Aleksandr L. Urakov, Natalya A. Urakova Aug 2024

Targeted Temperature Management In Obstetrics For Prevention Perinatal Encephalopathy, Aleksandr L. Urakov, Natalya A. Urakova

Turkish Journal of Medical Sciences

No abstract provided.