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Full-Text Articles in Physical Sciences and Mathematics

Investigation Of The Enzyme-Inhibitory, Antibacterial, And Anticancer Properties Of Metal Phthalocyanines, Meryem Topal, Fevzi̇ Topal, Firat Yilmaz, Esra Bulut Atalay, Ümi̇t Muhammet Koçyi̇ği̇t, Emre Güzel Apr 2026

Investigation Of The Enzyme-Inhibitory, Antibacterial, And Anticancer Properties Of Metal Phthalocyanines, Meryem Topal, Fevzi̇ Topal, Firat Yilmaz, Esra Bulut Atalay, Ümi̇t Muhammet Koçyi̇ği̇t, Emre Güzel

Turkish Journal of Chemistry

In this study, the enzyme inhibitory, antibacterial, and anticancer activities of a phthalonitrile derivative and its metal phthalocyanines (Pcs; indium, zinc, copper, cobalt, and manganese; 1–6) were investigated. The cobalt and manganese Pcs were synthesized for the first time in this study. The inhibitory activities of the symmetric Pcs, which were expected to interact with acetylcholinesterase (AChE) and butyrylcholinesterase (BChE) via their 4-(isopropylbenzyl)oxy substituents through host–guest interactions, were investigated. More selective inhibition of AChE than BChE was observed for these compounds. For AChE, CoPc was identified as the most potent inhibitor (IC50 = 14.81 nM), whereas for BChE, InPc was …


Templating Effect Of Neutral Dithiane Ligands On The Self-Assembly Of Cationic Au(I)-Phosphine Units, Farzane Osanlou, Abdollah Neshat, Mohammad Reza Yousefshahi, Vaclav Eigner, Michal Dusek, Shahram Seidi Apr 2026

Templating Effect Of Neutral Dithiane Ligands On The Self-Assembly Of Cationic Au(I)-Phosphine Units, Farzane Osanlou, Abdollah Neshat, Mohammad Reza Yousefshahi, Vaclav Eigner, Michal Dusek, Shahram Seidi

Turkish Journal of Chemistry

The interactions between the dinuclear Au(I) precursor (dppm)Au2Cl2 and neutral sulfur-containing dithianes (specifically 1,3- and 1,4-dithiane) were examined in the presence of NH₄PF₆. Although these sulfur-based ligands were initially employed to facilitate the formation of mixed phosphine/sulfur Au(I) complexes, single-crystal X-ray diffraction analysis revealed the unexpected generation of multinuclear Au(I) assemblies exclusively coordinated by phosphine ligands. When 1,3-dithiane was present, a trinuclear Au(I) complex was isolated, characterized by a central four-coordinate Au(I) center exhibiting a distorted see-saw geometry, flanked by two terminal Au(I) centers with T-shaped coordination environments. Importantly, the dithiane ligand did not coordinate directly to the gold centers …


Nucleophilic Cyclization Of N-Propargylated Pyrazole-5-Carboxylates: Synthesis Of Pyrazolo[1,5-A]Pyrazin-4(5h)-One Derivatives, Meli̇k Firat Mengeş, Meltem Tan Uygun Apr 2026

Nucleophilic Cyclization Of N-Propargylated Pyrazole-5-Carboxylates: Synthesis Of Pyrazolo[1,5-A]Pyrazin-4(5h)-One Derivatives, Meli̇k Firat Mengeş, Meltem Tan Uygun

Turkish Journal of Chemistry

Cyclization reactions are among the most important and widely used methods for synthesizing biologically active fused heterocyclic compounds. In the present study, pyrazolopyrazinone derivatives (10a–i) were synthesized from N-propargylated pyrazoles via nucleophilic cyclization with hydrazine hydrate under a nitrogen atmosphere. Nuclear magnetic resonance (NMR) spectral analyses confirmed that ring closure proceeded in a manner consistent with the formation of a six-membered pyrazinone moiety. In addition, the pyrazolotriazepinone derivative 15c was synthesized using an alternative approach. In this method, substitution with chloroacetone was first carried out, followed by ring closure with hydrazine hydrate, affording a seven-membered triazepinone system. Comparison of the …


From Stability To Spintronics: A Comprehensive High-Throughput Investigation Of 2d Mf4 Lieb Lattices, Uğur Yorulmaz Apr 2026

From Stability To Spintronics: A Comprehensive High-Throughput Investigation Of 2d Mf4 Lieb Lattices, Uğur Yorulmaz

Turkish Journal of Physics

The research on two-dimensional (2D) materials which have intrinsic magnetism and exotic electronic struc tures is an important quest in condensed matter physics. The Lieb lattice offers a unique platform for studying strongly correlated electron phenomena. In this work, we systematically investigated the structural, dynamical, mechanical, electronic, and magnetic properties of monolayer transition metal tetrafluorides (MF4, where M = Ag, Cd, Cr, Cu, Fe, Hf, Mn, Mo, Nb, Ni, Pd, Pt, Rh, Ru, Sc, Ta, Ti, V, W, and Y) arranged in a 2D Lieb lattice, using first-principles calculations based on density functional theory (DFT) with Hubbard (U) corrections. Our …


Two-Dimensional Inverse Scattering Solution Using Nurbs Expansion And A Deep Learning Method, Meisam Shafaee Apr 2026

Two-Dimensional Inverse Scattering Solution Using Nurbs Expansion And A Deep Learning Method, Meisam Shafaee

Turkish Journal of Physics

This paper presents a novel framework for solving two-dimensional (2D) inverse scattering problems by integrating nonuniform rational B-spline (NURBS) parameterization with convolutional neural networks (CNNs). Tra ditional pixel/voxel-based deep learning methods often suffer from high dimensionality and discretization artifacts, while purely geometric approaches lack robust inversion mechanisms. To address these limitations, we propose a hybrid frame work where the relative permittivity profile of an unknown scatterer is compactly represented as a NURBS surface, parameterized by a sparse set of control points and weights. This approach reduces the problem dimensionality over 16 times. On the other hand, using NURBS expansion ensures …


Analytical Solution Of The Green’S Functions For The Poisson Problem Outside A Disk, Mohammad Khorrami Apr 2026

Analytical Solution Of The Green’S Functions For The Poisson Problem Outside A Disk, Mohammad Khorrami

Turkish Journal of Physics

The Poisson problem in the space outside of a disk is investigated. Specifically, the Green’s function corresponding to the problem is calculated. The Green’s function equation is separable in terms of (oblate) ellipsoidal coordinates. Therefore, these coordinates are used to obtain a series expression for the Green’s function. This is done for both the Dirichlet and Neumann problems. The result is used to calculate the electric potential for some examples, with specific boundary conditions on a disk.


Long-Term Measurements Of Global Solar Radiation In Osmaniye, Türkiye (2014–2023), Muhi̇tti̇n Şahan, Hali̇de Şahan, Ramazan Kaya Apr 2026

Long-Term Measurements Of Global Solar Radiation In Osmaniye, Türkiye (2014–2023), Muhi̇tti̇n Şahan, Hali̇de Şahan, Ramazan Kaya

Turkish Journal of Physics

This paper presents the horizontal solar radiation data for Osmaniye (37◦04′N, 36◦22′E), located in Mediterranean region of Türkiye, over the period 2014–2023. Solar radiation variability, recorded at 1-min intervals, was evaluated in terms of hourly, daily, monthly, seasonal, and annual averages. Over the 10-year periods, the mean daily total and daily average global radiations received on a horizontal surface were 1,360,000 W/m2 and 371.47 W/m2, respectively. The monthly averaged daily global radiation (averaged over the 10-year period) ranged from 202.94 W/m2 in December to 496.86 W/m2 in July. The seasonal average values of solar radiations were 452.14 W/m2 in summer, …


Neotectonics Of The Malatya Basin, Se Türkiye; Implications Of The Reactivations Of The Faults Of The Basin During 6 February 2023 Earthquakes Of The East Anatolian Fault System, Yaşar Ergun Gökten, Doğan Kalafat Mar 2026

Neotectonics Of The Malatya Basin, Se Türkiye; Implications Of The Reactivations Of The Faults Of The Basin During 6 February 2023 Earthquakes Of The East Anatolian Fault System, Yaşar Ergun Gökten, Doğan Kalafat

Turkish Journal of Earth Sciences

The Malatya Basin (MB) is a fault-controlled superimposed sedimentary basin situated in the SE of Anatolia, near and to the north of the East Anatolian Fault System (EAFS). The rock units ranging from the Permo–Carboniferous to the Upper Miocene form the basin’s basement. The thickening of the Upper Cretaceous–Upper Miocene sequence toward the Malatya Fault (MF), the basin’s northwestern boundary, indicates a dip-slip-dominated character for the MF and its control on the first-step sedimentation of the basin. The MF changes its character from dip-slip normal to the strike-slip in the Late Pliocene, and today presents a 1700-m left lateral offset, …


Geochemistry Of The Upper Jurassic–Lower Cretaceous Limestone Of The Bilecik Formation In The Dümrek Area (Eskişehir, Western Central Anatolia): Implications For Depositional Environment And Paleotemperature, Asuman Kahya, Meti̇n Bağci Mar 2026

Geochemistry Of The Upper Jurassic–Lower Cretaceous Limestone Of The Bilecik Formation In The Dümrek Area (Eskişehir, Western Central Anatolia): Implications For Depositional Environment And Paleotemperature, Asuman Kahya, Meti̇n Bağci

Turkish Journal of Earth Sciences

Upper Jurassic–Lower Cretaceous limestones of the Bilecik Formation are exposed near the village of Dümrek (Eskişehir Province) within the Sakarya Zone. Mineralogical analyses reveal that these limestones are predominantly composed of calcite and include intraclasts, fossil shell fragments, ooids, and peloids, cemented by sparry and micritic calcite. The U/Th, Ni/Co, V/(V+Ni), V/Cr, and Ce/Ce* ratios indicate that these carbonates were deposited in an oxic environment. Furthermore, the Mn/Sr ratios imply no diagenetic alteration, indicating preservation of the original geochemical signature. The PAAS-normalized REE+Y patterns of these limestones display depletion in light rare earth elements, a pronounced positive La anomaly (La/La* …


Burdigalian–Langhian Flora Of The Çan–Etili (Çanakkale) Basin, Compared With Those Of Western Türkiye, Sari̇ye Duygu Durak, Mehmet Serkan Akki̇raz Mar 2026

Burdigalian–Langhian Flora Of The Çan–Etili (Çanakkale) Basin, Compared With Those Of Western Türkiye, Sari̇ye Duygu Durak, Mehmet Serkan Akki̇raz

Turkish Journal of Earth Sciences

A palaeofloristic study was carried out on Lower–Middle Miocene deposits of western Türkiye (Çan–Etili Basin). The sediments of the Çan–Etili Basin, which were obtained from measured sections, were deposited in a continental environment. The palaeovegetation of the Çan–Etili Basin (Kazım Oğlak and Keçiağılı successions) during the Early–Middle Miocene was mainly made up of evergreen and deciduous mixed forests (Castanea–Castanopsis, Cyrillaceae–Clethraceae, Engelhardia, Quercus evergreen-type, Quercus deciduous-type), riparian vegetation with high quantities of Alnus and conifers such as Pinus haploxylon-type, Pinus diploxylon-type, and undifferentiated Pinaceae. The reconstructed palaeoclimate data from the palaeoflora (pollen and leaves) imply a warm and temperate climate, with …


Integrated Dinsar And Hvsr Microtremor Analysis For Understanding Ground Deformation And Site Effects: Case Study Of The Bawean Earthquake (M6.5), Joshua Purba, Muhammad Fikri Hayqal Hiola, Ramadhan Priadi, Riska Yulinda, Iham Ilham, Rosa Amelia Mar 2026

Integrated Dinsar And Hvsr Microtremor Analysis For Understanding Ground Deformation And Site Effects: Case Study Of The Bawean Earthquake (M6.5), Joshua Purba, Muhammad Fikri Hayqal Hiola, Ramadhan Priadi, Riska Yulinda, Iham Ilham, Rosa Amelia

Turkish Journal of Earth Sciences

This study investigates the seismic hazards of Bawean Island following a recent M6.5 earthquake using an integrated approach combining differential interferometric synthetic aperture radar (DInSAR) and horizontal-to-vertical spectral ratio (HVSR) methodologies. The DInSAR analysis revealed ground deformation characterized by subsidence up to 10 cm and uplift up to 8 cm, correlating with the region’s strike-slip fault dynamics. HVSR analysis provided insights into site amplification effects, identifying zones with low Vs30 values (153.77–454.72 m/s), high amplification factors (A0), and elevated seismic vulnerability index values (Kg). The dominant frequency (f0) on Bawean Island ranges from 0.64 to 17.76 Hz, with most areas …


Numerical Study Of Porosity Effects On Temperature And Fluid Flow In Black Sea Gas Hydrates, Bahar Güvem, Doğa Doğan Mar 2026

Numerical Study Of Porosity Effects On Temperature And Fluid Flow In Black Sea Gas Hydrates, Bahar Güvem, Doğa Doğan

Turkish Journal of Earth Sciences

Numerical temperature and fluid flow simulations were conducted using ANSYS Fluent to investigate the influence of porosity variations on the temperature distribution within the gas hydrate layer. The study was carried out in the Black Sea region, where the gas hydrate deposits are of particular interest due to their potential for energy resources. The simulations explored various porosity levels within the hydrate layer to observe their effect on thermal behavior and fluid dynamics. The results revealed that porosity plays a significant role in modulating the temperature distribution within the gas hydrate layer, with lower porosity models exhibiting higher temperatures compared …


Effects Of Seismic Filters On Pretrained Cnn Models For Fault Detection: Application To The Delft 3d Seismic Volume, The Netherlands, Süleyman Alemdar, Ertan Pekşen Mar 2026

Effects Of Seismic Filters On Pretrained Cnn Models For Fault Detection: Application To The Delft 3d Seismic Volume, The Netherlands, Süleyman Alemdar, Ertan Pekşen

Turkish Journal of Earth Sciences

Accurate mapping of faults from 3D seismic volumes is critical for identifying structural traps, assessing reservoir compartmentalization, and guiding drilling decisions. This study evaluates how common seismic conditioning filters affect both the visual quality of a production Delft 3D poststack time-migrated volume and the outputs of two pretrained 3D CNN fault detectors: UNet3D and FaultNet. Seven filters were applied independently—AJAX, DeSmile, SimpleDenoise, Dip-Steered Median Filter (DSMF), Edge-Preserving Smoother (EPS), Fault Enhancement, and Ridge Enhancement—and results were inspected across inline, crossline, time-slice, and full-cube perspectives. The analysis is image-driven, supported by high-resolution comparison figures and view-specific interpretations.Filters that suppress incoherent noise …


Cover And Contents Mar 2026

Cover And Contents

Turkish Journal of Electrical Engineering and Computer Sciences

No abstract provided.


Sentisec: Combining Keyword Heuristics And Sentiment Modeling For Ai-Powered Threat Detection, Ridho Surya Kusuma, Erum Ashraf, Selvakumar Manickam, Shankar Karuppayah Mar 2026

Sentisec: Combining Keyword Heuristics And Sentiment Modeling For Ai-Powered Threat Detection, Ridho Surya Kusuma, Erum Ashraf, Selvakumar Manickam, Shankar Karuppayah

Turkish Journal of Electrical Engineering and Computer Sciences

This work presents SENTISEC, a hybrid LLM-based threat detection framework designed to classify security logs by integrating keyword heuristics, domain-adapted sentiment scoring, and Retrieval-Augmented Generation (RAG). The system achieves an overall accuracy of 93.67%, with 91.46% macro recall, 89.07% macro F1, and 95.15% threat recall, while maintaining a low false-positive rate of 1.68%. Its methodology incorporates strict keyword and IOC matching, a domain-tuned DistilBERT sentiment module, hybrid BM25–MiniLM retrieval enhanced with BGE reranking, adaptive quantile-based threshold calibration, and SHAP-based explainability. Comparative evaluations against keyword-only, sentiment-only, classical machine-learning models, and DistilBERT-only baselines show that SENTISEC consistently improves both true-positive and true-negative …


Sgsc-Kko-Lstm: A Deeplearning Classifier Model For Smart Grid, Dushmanta Kumar Das, Samaniba Imchen Mar 2026

Sgsc-Kko-Lstm: A Deeplearning Classifier Model For Smart Grid, Dushmanta Kumar Das, Samaniba Imchen

Turkish Journal of Electrical Engineering and Computer Sciences

Maintaining smart grid stability is crucial for the reliable operation of decentralized electricity networks, especially as the energy sector becomes more complex. The process of ensuring grid stability begins with collecting consumer data and comparing it to power supply requirements. Ultimately, consumers receive a report showing their energy use and pricing details. However, this process is time-consuming and can be improved by leveraging artificial intelligence to predict smart grid stability more efficiently. Specifically, an optimized Long Short-Term Memory (LSTM) network is proposed to predict smart grid stability, addressing the challenges associated with traditional data collection and evaluation methods. Simulations from …


A Joint Optimization-Based Novel Attack For Genomic Beacon Reconstruction, Kousar Saleem, Si̇nem Sav Mar 2026

A Joint Optimization-Based Novel Attack For Genomic Beacon Reconstruction, Kousar Saleem, Si̇nem Sav

Turkish Journal of Electrical Engineering and Computer Sciences

Genomic data sharing has become an essential component of biomedical research, enabling large-scale collaborations and accelerating discoveries in human genetics. To balance the need for accessibility with privacy concerns, several controlled-access mechanisms have been proposed, including genomic beacons. Genomic beacons answer simple presence/absence queries about specific genetic variants. However, prior work has demonstrated that beacons remain vulnerable to genome reconstruction attacks, where an adversary can recover large portions of participants’ genomes using summary statistics. Building on insights from prior reconstruction attacks, we introduce an approach that unifies SNP correlation and allele frequency alignment objectives within a single-stage joint optimization framework. …


Automated Software Size Measurement Using Multilingual Domain-Adapted Language Models, Samet Tenekeci̇, Hüseyi̇n Ünlü, Burak Keçeci̇, Muhammed Efe İnci̇r, Onur Demi̇rörs Mar 2026

Automated Software Size Measurement Using Multilingual Domain-Adapted Language Models, Samet Tenekeci̇, Hüseyi̇n Ünlü, Burak Keçeci̇, Muhammed Efe İnci̇r, Onur Demi̇rörs

Turkish Journal of Electrical Engineering and Computer Sciences

Software Size Measurement (SSM) is crucial for estimating required project effort as well as budget and schedule. However, many small and medium-sized companies struggle to apply objective SSM due to limited resources and lack of expertise. This often leads to inaccurate estimates and project overruns. There is a need for practical, low-resource solutions that support these tasks without requiring expert involvement. Motivated by this challenge, this study proposes an automated software size measurement approach that formulates the measurement task as supervised regression over natural language requirements, using domain-adapted transformer models. We construct large-scale Turkish and English software engineering corpora to …


Reducing Complexity In Versatile Video Coding Intra-Coding Through Machine Learning-Based Optimization Of Partitioning And Prediction, Amina Kessentini, Amna Maraoui, Imen Werda, Fatma Ezahra Sayadi Mar 2026

Reducing Complexity In Versatile Video Coding Intra-Coding Through Machine Learning-Based Optimization Of Partitioning And Prediction, Amina Kessentini, Amna Maraoui, Imen Werda, Fatma Ezahra Sayadi

Turkish Journal of Electrical Engineering and Computer Sciences

The escalating demand for high-resolution multimedia content has necessitated more efficient video compression solutions. The Versatile Video Coding (VVC) standard, despite achieving remarkable compression gains, introduces significant computational complexity, primarily due to its exhaustive Rate-Distortion Optimization (RDO) process. To address this, we propose an intelligent approach leveraging supervised machine learning techniques to streamline the VVC encoding process. Specifically, we introduce a Lightweight Neural Network (LNN) for efficient coding unit partitioning decisions and a Decision Tree (DT) classifier for optimizing the intra prediction process. This dual-method framework, tailored for All Intra coding configuration, significantly reduces encoder complexity while maintaining compression performance …


Designing Risk-Aware Mixed-Mode Evacuation Strategies For Tsunamis: Insights From İstanbul, Vedat Bayram, Doruk Ergez, Ada Arikanoğlu Mar 2026

Designing Risk-Aware Mixed-Mode Evacuation Strategies For Tsunamis: Insights From İstanbul, Vedat Bayram, Doruk Ergez, Ada Arikanoğlu

Turkish Journal of Electrical Engineering and Computer Sciences

​Tsunamis pose severe and time-critical risks to densely populated coastal cities, where limited warning times and infrastructure constraints demand carefully coordinated evacuation strategies. This study develops an integrated, risk-aware optimization framework that jointly considers vertical and horizontal sheltering options together with mixed pedestrian-vehicular evacuation dynamics. The proposed mixed-integer second-order cone programming (MISOCP) model simultaneously determines vertical shelter location, evacuee assignment, road-use designation for pedestrians and vehicles, and route selection under congestion, capacity, and budget constraints. Vehicle travel times incorporate congestion effects through a convex flow-dependent function, while pedestrian routing ensures convergent and conflict free evacuation paths. A risk-minimization objective accounts …


Optimal Network Reconfiguration Based On Discrete Metaheuristic Techniques For Reduction Of Power Loss And Carbon Emission In Distribution Networks, Asad Ali, Hazlie Mokhlis, Nurulafiqah Nadzirah Mansor, Hussain Shareef, Hasmaini Mohamad, Munir Azam Muhammad Mar 2026

Optimal Network Reconfiguration Based On Discrete Metaheuristic Techniques For Reduction Of Power Loss And Carbon Emission In Distribution Networks, Asad Ali, Hazlie Mokhlis, Nurulafiqah Nadzirah Mansor, Hussain Shareef, Hasmaini Mohamad, Munir Azam Muhammad

Turkish Journal of Electrical Engineering and Computer Sciences

Power distribution systems play a crucial role in transmitting electrical power from generation sources to end users. During transmission, significant power losses occur in the form of heat as the current flowing along the lines/cables has resistance. To minimize power losses, distribution network reconfiguration (DNR) has been widely adopted. This paper proposes optimal DNR based on metaheuristic techniques with discrete mutation feature targeting active power loss reduction, which subsequently lowers carbon emissions and operational costs. Through the discrete mutation feature, computational time to find optimal solution has been reduced significantly with fewer iterations compared to conventional mutation techniques. The proposed …


Enhanced Antenna Selection Techniques For Energy-Efficient Code Index Modulation Aided Spatial Modulated Wireless Communication Systems, Fati̇h Çögen, Burak Ahmet Özden, Erdoğan Aydin Mar 2026

Enhanced Antenna Selection Techniques For Energy-Efficient Code Index Modulation Aided Spatial Modulated Wireless Communication Systems, Fati̇h Çögen, Burak Ahmet Özden, Erdoğan Aydin

Turkish Journal of Electrical Engineering and Computer Sciences

This study proposes an integrated multiple-input multiple-output (MIMO) transceiver framework, termed CIM-HQAM-SM, which combines code index modulation (CIM) and spatial modulation (SM) with energy-efficient hexagonal quadrature amplitude modulation (HQAM). In the proposed bit mapping, the information bits jointly select (i) the active transmit-antenna index, (ii) the Walsh–Hadamard spreading-code indices for the in-phase and quadrature branches, and (iii) an HQAM symbol. Hence, the payload is conveyed through the constellation symbol as well as through antenna and code indices. For the considered Rayleigh-fading scenarios and matched spectral-efficiency settings, the proposed framework offers BER improvements over conventional SM and quadrature SM (QSM), while …


An Ensembled Two-Phase Deep Learning Approach For A Psychiatric Disorder Detection, Prajna Paramita Debata, Midhun Chakkaravarthy, Brojo Kishore Mishra Mar 2026

An Ensembled Two-Phase Deep Learning Approach For A Psychiatric Disorder Detection, Prajna Paramita Debata, Midhun Chakkaravarthy, Brojo Kishore Mishra

Turkish Journal of Electrical Engineering and Computer Sciences

Computational Psychiatry represents a burgeoning realm within scientific inquiry, delving into the intricate interplay of neurobiology within the brain. The escalating prevalence of mental illness underscores the urgency to confront this challenge. Among the prevalent disorders, Schizophrenia and Bipolar Disorder loom large, affecting a significant portion of the population at some point in their lives. However, pinpointing psychiatric disorders poses a formidable challenge. Genetic predispositions significantly influence the development of mental illnesses, with intriguing overlaps observed among certain disorders. This convergence complicates accurate diagnosis. Here, a deep learning approach is considered for significant gene biomarker identification and classification of Schizophrenia …


The Degree Of Nondensifiability In Hausdorff Locally Convex Topological Vector Spaces And Applications, Gonzalo Garcia Mar 2026

The Degree Of Nondensifiability In Hausdorff Locally Convex Topological Vector Spaces And Applications, Gonzalo Garcia

Turkish Journal of Mathematics

The so called degree of nondensifiability, DND, has been studied in Banach spaces through several studies, and some fixed point results using the DND have been proved. In the present paper, we extend the concept of DND to a Hausdorff locally convex topological vector space (LCTVS). Its main properties, as well as the differences between the DND in Banach spaces and the DND in a LCTVS, are analyzed. Furthermore, under suitable conditions, we provide some fixed point results in a LCTVS by using the DND, and as an application, we prove the existence of solutions of certain Volterra integral equations.


Existence Of Positive Periodic Solutions For A First-Order Semilinear Functional Differential Equation With An Iterative Source Term, Ahlème Bouakkaz, Rabah Khemis Mar 2026

Existence Of Positive Periodic Solutions For A First-Order Semilinear Functional Differential Equation With An Iterative Source Term, Ahlème Bouakkaz, Rabah Khemis

Turkish Journal of Mathematics

In this paper, we will establish the existence of positive periodic solutions for a class of first order iterative functional differential equations by using a powerful and effective technique based on the Krasnoselskii fixed point theorem together with some useful properties of a Green's function. The obtained results that complement some previous works, are illustrated with an example.


Simplicity In Le-Semigroups Via Partitions Of Full Words, And Its Applications To Regularity Conditions Induced By Linear Inequalities, Nareupanat Lekkoksung Mar 2026

Simplicity In Le-Semigroups Via Partitions Of Full Words, And Its Applications To Regularity Conditions Induced By Linear Inequalities, Nareupanat Lekkoksung

Turkish Journal of Mathematics

The concept of simplicity in le-semigroups has been used to characterize the coincidence of ideal elements and to study Khayopulu–Green’s relations. Several types of simplicities are known, including two-sided simplicity, left simplicity, right simplicity, bisimplicity, quasisimplicity, and biinterior simplicity. A natural question arises: are there further notions of simplicity for le-semigroups? If so, how are they related? By employing the notion of partition ideal elements, we observe that several potential simplicities have not yet been explored. In this paper, we introduce new forms of simplicity in le-semigroups defined via partitions of full words, and we investigate the …


On The Semigroups Of Order-Preserving And Orientation-Preserving Full Contraction Mappings On A Finite Chain, Gonca Ayik, Hayrullah Ayik Mar 2026

On The Semigroups Of Order-Preserving And Orientation-Preserving Full Contraction Mappings On A Finite Chain, Gonca Ayik, Hayrullah Ayik

Turkish Journal of Mathematics

Let OPCTn (OCTn) denote the semigroup consisting of all orientation-preserving (order-preserving) full contraction mappings on the finite chain Xn = {1 < ··· < n}, and let OPDCTn (ODCTn) denote the subsemigroup of OPCTn (OCTn) consisting of all order-decreasing transformations. The purpose of this paper is to determine the cardinalities of OPCTn, OPDCTn, N(ODCTn), and N(OPDCTn), and to identify generating sets of minimal size, thereby determining their ranks. Moreover, the number of idempotents of OPDCTn is determined.


A Geometric Property Characterizing The 3d-Generalized Clothoids, Pascual Lucas, José-Antonio Ortega-Yagües Mar 2026

A Geometric Property Characterizing The 3d-Generalized Clothoids, Pascual Lucas, José-Antonio Ortega-Yagües

Turkish Journal of Mathematics

In this paper, we study 3D-generalized clothoids, defined as curves for which there exists another distinct curve, with proportional arclength parameter, such that the Darboux lines of both curves at corresponding points are the same. We prove that these curves are those for which the ratio of torsion and curvature τ/κ is a linear rational function of the arclength. We also show that any 3D-generalized clothoid can be constructed from a rectifying curve, which is of constant curvature in the case of a 3D-clothoid.


Multiplicative Lorentz Matrix Multiplication And The Motion On Multiplicative Lorentz Plane, Osman Keçi̇li̇oğlu, İlayda Durmaz, Hali̇t Gündoğan Mar 2026

Multiplicative Lorentz Matrix Multiplication And The Motion On Multiplicative Lorentz Plane, Osman Keçi̇li̇oğlu, İlayda Durmaz, Hali̇t Gündoğan

Turkish Journal of Mathematics

In this paper, we define the multiplicative determinant for general n×n matrices, extending previous studies that were limited to lower-dimensional cases. Additionally, we introduce a novel matrix multiplication operation based on the multiplicative Lorentz inner product and conduct a thorough investigation of its algebraic properties. Furthermore, we explore rotational and reflectional transformations in the two-dimensional multiplicative Lorentz space L*2, supported by illustrative examples of these geometric motions.


Investigation Of The Behavior Of Biparametric Potentials Associated With The Laplace-Bessel Differential Operator In Weighted Lebesgue Spaces, Çağla Seki̇n Mar 2026

Investigation Of The Behavior Of Biparametric Potentials Associated With The Laplace-Bessel Differential Operator In Weighted Lebesgue Spaces, Çağla Seki̇n

Turkish Journal of Mathematics

In this article, we investigate the mapping properties of potential-type operators of the form Jαβ = (E + (−Δν)β/2)−α/β, (β, α > 0), where Δν is the Laplace-Bessel differential operator. We establish norm inequalities that describe the boundedness of the operator Jαβ from Lp,ν to Lq,ν under suitable conditions on α, β, p and q. The results extend and unify the known estimates for classical potential operators. In particular, the cases β = 1 and β = 2 correspond to the modified Flett and Bessel potentials, respectively.