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Articles 1 - 30 of 10694
Full-Text Articles in Physical Sciences and Mathematics
On Families Of Finsler Metrics, İsmai̇l Sağlam, Ken'ichi Ohshika, Athanase Papadopoulos
On Families Of Finsler Metrics, İsmai̇l Sağlam, Ken'ichi Ohshika, Athanase Papadopoulos
Turkish Journal of Mathematics
In this paper, we answer some natural questions concerning symmetrisation and more general combinations of Finsler metrics, with a view to applications to Funk and Hilbert geometries and metrics on Teichmüller spaces. The metrics on Teichmüller space that we consider are the Thurston metric and the earthquake metric, both introduced by Thurston. The first metric has been thoroughly studied over the last couple of decades, and the second over the last few years. The Funk metric and its symmetrisation, the Hilbert metric, are classical metrics that have been investigated in the contexts of hyperbolic geometry and geometric function theory and, …
On The Monoid Of Partial Order-Preserving Transformations Of A Finite Chain Whose Domains And Ranges Are Intervals, Hayrullah Ayik, Vítor H. Fernandes, Emrah H. Korkmaz
On The Monoid Of Partial Order-Preserving Transformations Of A Finite Chain Whose Domains And Ranges Are Intervals, Hayrullah Ayik, Vítor H. Fernandes, Emrah H. Korkmaz
Turkish Journal of Mathematics
In this paper, we consider the monoid PIOn of all partial order-preserving transformations on a chain with n elements whose domains and ranges are intervals, along with its submonoid PIOn− of order-decreasing transformations. Our main aim is to give presentations for PIOn− and PIOn. Moreover, for both monoids, we describe regular elements and determine their ranks, cardinalities and the numbers of idempotents and nilpotents.
Stochastic Control Of Inventory And Scheduling Decisions In An Open Network Of Repairables, Erhun Özkan
Stochastic Control Of Inventory And Scheduling Decisions In An Open Network Of Repairables, Erhun Özkan
Turkish Journal of Mathematics
We study maintenance operations for capital goods with repairable components. Because the downtime of a capital good is costly, the maintenance provider keeps an inventory of spare parts to quickly replace broken parts of the capital goods. After the replacement, the broken part is added to the repair facility’s repair queue. Upon a part breakdown, if there is no spare part in the inventory, then the maintenance provider has two options: (i) it can backorder the spare part demand, (ii) it can execute an emergency repair, which is done immediately and quickly, and is followed by a quick installation of …
A Full-Scale Watertight Workflow Numerical Study For A Triangular Fin And Tube Heat Exchanger, Hamdi̇ Selçuk Çeli̇k, Bahadir Doğan, Lati̇fe Berri̇n Erbay
A Full-Scale Watertight Workflow Numerical Study For A Triangular Fin And Tube Heat Exchanger, Hamdi̇ Selçuk Çeli̇k, Bahadir Doğan, Lati̇fe Berri̇n Erbay
Turkish Journal of Mathematics
In this study, the thermo-hydraulic characteristics of an air-cooled triangular finned tube heat exchanger were analyzed numerically. The full-scale heat exchanger was modeled using Ansys Fluent watertight workflow, considering water as the primer fluid to precisely investigate the effects of geometrical factors. The effects of fin height, fin width, and fin spacing of the triangular fins on the performance of the heat exchanger were examined using k-ω turbulence model. A basic finned-tube heat exchanger model, which was manufactured as a monolithic structure without tube-fin contact resistance by milling from aluminum 5083 material, was tested in an air tunnel to verify …
Characterizations Of Bi-Riordan Arrays, Nai̇m Tuğlu, Fatma Yeşi̇l Baran
Characterizations Of Bi-Riordan Arrays, Nai̇m Tuğlu, Fatma Yeşi̇l Baran
Turkish Journal of Mathematics
In this study, we introduce the concept of a bi-Riordan array. As part of this construction, we define new composition and power operations. We then establish an analogue of the well-known fundamental theorem of Riordan arrays (FTRA), which we call the fundamental theorem of bi-Riordan arrays. Next, we show that the product of two bi-Riordan matrices is again a bi-Riordan matrix. Using this product structure, we prove that the set of bi-Riordan matrices forms a monoid.
Compact And Am-Compact Orthogonally Additive Operators, Bahri̇ Turan, Bi̇rol Altin
Compact And Am-Compact Orthogonally Additive Operators, Bahri̇ Turan, Bi̇rol Altin
Turkish Journal of Mathematics
We show that compactness of orthogonally additive operators between Banach lattices is not preserved under taking the modulus by providing a nonlinear analogue of Krengel’s example. In contrast, for operators acting from a Banach lattice into an AM-space, AM-compactness is stable under lattice operations. Moreover, the space of absolutely norm bounded AM-compactorthogonally additive operators from a Banach lattice into an AM-space is a Banach lattice, and on such AM-spaces with the weak Fatou property, norm boundedness coincides with absolute norm boundedness.
Generalized Spectral Bound For Quasi-Twisted Codes, Buket Özkaya
Generalized Spectral Bound For Quasi-Twisted Codes, Buket Özkaya
Turkish Journal of Mathematics
Minimum distance bounds play a central role in the analysis of algebraic codes. For cyclic and constacyclic codes, several bounds based on their zero set have been developed. However, analogous results for quasi-twisted (QT) codes are comparatively limited. In this paper, we further investigate the spectral theory of QT codes and derive a general spectral bound on their minimum distance. Our bound unifies and generalizes previously known spectral bounds for quasi-cyclic (QC) and QT codes, and contains them as special cases. We present a new proof technique and show that the bound can be formulated with respect to an arbitrary …
A Novel Iterative Algorithm For Approximating Common Fixed Points Of Generalized Α-Nonexpansive Multivalued Mappings In Kohlenbach Hyperbolic Spaces, Makbule Kaplan Özekes
A Novel Iterative Algorithm For Approximating Common Fixed Points Of Generalized Α-Nonexpansive Multivalued Mappings In Kohlenbach Hyperbolic Spaces, Makbule Kaplan Özekes
Turkish Journal of Mathematics
In this paper, we propose a new iterative scheme involving three multivalued mappings in Kohlenbach hyperbolic spaces. Strong and ∆-convergence theorems are established for approximating common fixed points of nonexpansive multivalued mappings under suitable conditions. A numerical example is also presented to illustrate the efficiency and faster convergence of the proposed method. The results obtained extend and unify several related contributions in the existing literature.
On The Generalized Cesàro Sequence Spaces And Some Of Their Properties, Uğur Gönüllü, Faruk Polat, Martin Richard Weber
On The Generalized Cesàro Sequence Spaces And Some Of Their Properties, Uğur Gönüllü, Faruk Polat, Martin Richard Weber
Turkish Journal of Mathematics
Let Ct = (cnm)n,m∈ℕ denote the generalized Cesàro matrix defined by cnm = tn−m/n for m ≤ n and t ∈ [0, 1], and cnm = 0 otherwise. For each q ∈ [1, ∞), the associated generalized Cesàro sequence spaces cesqt are introduced. These spaces form Banach lattices under the coordinatewise order, equipped with a naturally defined order continuous norm. We prove that cesqt = cesq0 for all t ∈ [0, 1) and q ∈ [1, ∞), implying that the space …
Exponential Stability For A Strongly Damped Wave Equation With Distributed Internal Delay, Manal Alotaibi, Nasser-Eddine Tatar, Waled Al-Khulaif
Exponential Stability For A Strongly Damped Wave Equation With Distributed Internal Delay, Manal Alotaibi, Nasser-Eddine Tatar, Waled Al-Khulaif
Turkish Journal of Mathematics
This paper investigates the exponential stability of a strongly damped wave equation subject to an internal distributed time delay. Two distinct analytical frameworks are developed: the first employs a modified energy method based on auxiliary functionals, while the second introduces a transformation that rewrites the delay term as the derivative of a convolution integral. Both approaches yield explicit decay conditions and establish exponential convergence of the energy under weaker assumptions on the damping coefficient and the delay kernel. Notably, the transformation method allows for a wider class of admissible delay weights than those permitted by classical techniques. Numerical simulations based …
Clairaut Conformal Submersions From Ricci Solitons, Murat Polat
Clairaut Conformal Submersions From Ricci Solitons, Murat Polat
Turkish Journal of Mathematics
In this study, we investigate Clairaut conformal submersions in the context of total manifolds that support a Ricci soliton structure. We begin by deriving the scalar curvature and Ricci tensor expressions associated with these manifolds, and we establish criteria under which the fibres can be characterized as almost Ricci solitons or Einstein manifolds. Additionally, we identify the conditions required for the base manifold to admit Ricci soliton and Einstein structures. We also determine the necessary conditions for a vector field ζ to be conformal or Killing. Moreover, we demonstrate that when the potential vector field of the Ricci soliton is …
A Delayed Siamr Prostate Cancer Model With Vertical Transmission And Treatment: Stability Analysis And Numerical Simulation, Hüseyi̇n Demir, İnci̇ Çi̇li̇ngi̇r Süngü, İbrahi̇m Keles
A Delayed Siamr Prostate Cancer Model With Vertical Transmission And Treatment: Stability Analysis And Numerical Simulation, Hüseyi̇n Demir, İnci̇ Çi̇li̇ngi̇r Süngü, İbrahi̇m Keles
Turkish Journal of Mathematics
In this paper, we propose and analyse a delayed-compartmental mathematical model of prostate cancer dynamics that incorporates vertical transmission and therapeutic intervention. The population is stratified into five compartments: susceptible (S), infected/virally activated (I), asymptomatic infectious under treatment (A), malignant untreated (M), and recovered (R). A discrete time delay τ > 0 is introduced in the force-of-infection term to model the age-dependent onset of susceptibility in middle-aged adult males. Vertical transmission of viral etiology at a rate qΛ ensures that a fraction of newborns enter the infected compartment directly, rendering the disease persistent regardless of the basic reproduction number R₀. We …
Hyers-Ulam And Hyers-Ulam Rassias Stability Of Caputo Fractional Hahn Difference Equations, Karima Mohamed Oraby, Alaa E. Hamza, Afrah Al-Bossly
Hyers-Ulam And Hyers-Ulam Rassias Stability Of Caputo Fractional Hahn Difference Equations, Karima Mohamed Oraby, Alaa E. Hamza, Afrah Al-Bossly
Turkish Journal of Mathematics
In this paper, we investigate Hyers–Ulam and Hyers–Ulam–Rassias stability for fractional linear Hahn difference equations of Caputo Type. To the best of our knowledge, this is the first work concerning Hyers–Ulam type stability in the framework of Caputo fractional Hahn difference equations, thereby filling a significant gap in the literature on fractional stability theory. Our approach is based on establishing an equivalence between the fractional Hahn difference initial value problem and a corresponding fractional integral equation, via the Caputo–Hahn inversion formula. These results lay a strong groundwork for analyzing the stability of Hahn fractional systems, which could be useful in …
A Note On The Periodic Orbits Of Wolbachia Spread Dynamics In Mosquito Populations In Periodic Environments, Jose S. Cánovas
A Note On The Periodic Orbits Of Wolbachia Spread Dynamics In Mosquito Populations In Periodic Environments, Jose S. Cánovas
Turkish Journal of Mathematics
We consider the periodic model introduced by B. Zheng and J. Yu, and disprove the conjectures on the number of periodic orbits the model can have. We rebuild the conjecture to prove that for periodic sequences of maps of any period, the number of nonzero periodic trajectories is bounded by two.
Folic Acid-Targeted Polymeric Complex Imprinted With Doxorubicin And Quercetin For Controlled Drug Delivery In Cancer Therapy, Ceren Türkcan, Emi̇rhan İşeri̇
Folic Acid-Targeted Polymeric Complex Imprinted With Doxorubicin And Quercetin For Controlled Drug Delivery In Cancer Therapy, Ceren Türkcan, Emi̇rhan İşeri̇
Turkish Journal of Chemistry
Cancer therapy is often limited by the systemic toxicity and dose-dependent adverse effects of conventional chemotherapeutic agents such as doxorubicin (DOX). In this study, a folic acid-functionalized molecularly imprinted polymeric complex based on poly(HEMA) crosslinked with ethylene glycol dimethacrylate was synthesized for the controlled release of DOX in combination with quercetin (QUE), a flavonoid known for its antioxidant and chemosensitizing properties. The aim of this work was to develop and physicochemically characterize a preliminary targeted drug delivery platform at a material-design level. The polymeric complex was synthesized via free-radical polymerization following a DOX–QUE precomplex formation step. Structural characterization was performed …
A Poly-L-Lysine-Functionalized Electrochemical Immunosensor Enables Highly Sensitive Detection Of Tumor Necrosis Factor Receptor-Associated Protein 1, Berfi̇n Vural, Mustafa Kemal Sezgi̇ntürk
A Poly-L-Lysine-Functionalized Electrochemical Immunosensor Enables Highly Sensitive Detection Of Tumor Necrosis Factor Receptor-Associated Protein 1, Berfi̇n Vural, Mustafa Kemal Sezgi̇ntürk
Turkish Journal of Chemistry
Tumor necrosis factor receptor-associated protein 1 (TRAP-1), a member of the mitochondrial heat shock protein family (HSP90), is essential for protein homeostasis, stress response, and cell cycle. TRAP-1 not only optimizes cellular energy production but also prevents cell death, thereby supporting the survival and proliferation of tumor cells. In addition to cancer, TRAP-1 has been associated with Parkinson’s disease, certain autoimmune disorders, and abnormalities in the kidney and urinary tract. In this study, a unique and useful indium tin oxide-polyethylene terephthalate (ITO–PET)-based electrochemical biosensor is described for detecting the biomarker TRAP-1. The ITO–PET electrode, selected as the working electrode, is …
Aptamer–Gold Nanoparticle-Based Lab-In-A-Tube Colorimetric Detection Of Malathion: Evaluation With Classical And Digital Readout Techniques, Emi̇ne Güler Çeli̇k
Aptamer–Gold Nanoparticle-Based Lab-In-A-Tube Colorimetric Detection Of Malathion: Evaluation With Classical And Digital Readout Techniques, Emi̇ne Güler Çeli̇k
Turkish Journal of Chemistry
Colorimetric biosensing devices represent an important class of point-of-care (POC) diagnostics due to their ability to provide visible test outputs, their ease of integration with smartphone-based sensing, and their portability for field testing. In the context of agrifood safety, there is a growing need for portable, robust, and cost-effective detection devices. Pesticide residues can be present in a wide range of environmental and food samples, from water resources to fruits and vegetables, resulting in an increasing global demand for on-site testing. Colorimetric assays, when combined with smartphone-based sensing, can effectively address these needs. In this work, the aggregation-induced color change …
Sensitive Electrochemical Sensor For Simultaneous Determination Of Epinephrine And Norepinephrine By Sio2np@Mwcnt-Cooh Nanoparticle-Modified Spces, Merve Yilmaz Çilçar, Meli̇ke Bi̇lgi̇ Kamaç, Ayşenur Yilmaz Kabaca, Şahi̇n Toparli, Faruk Terzi̇oğlu, Emi̇r Ateş
Sensitive Electrochemical Sensor For Simultaneous Determination Of Epinephrine And Norepinephrine By Sio2np@Mwcnt-Cooh Nanoparticle-Modified Spces, Merve Yilmaz Çilçar, Meli̇ke Bi̇lgi̇ Kamaç, Ayşenur Yilmaz Kabaca, Şahi̇n Toparli, Faruk Terzi̇oğlu, Emi̇r Ateş
Turkish Journal of Chemistry
Epinephrine (EP) and norepinephrine (NEP), both neurotransmitters, are two important biomolecules that play critical roles in the body, from the central nervous system to metabolic processes. They are also important biomarkers for clinical diagnosis and monitoring. In this study, a novel, fast, practical, and high-performance electrochemical sensor based on a SiO2NP@MWCNT-COOH nanocomposite was developed for the simultaneous determination of EP and NEP. The nanocomposite was modified onto the surface of screen-printed electrodes (SPCEs) and its characterization was performed (SEM-EDX, XRD, FTIR, CV, DPV, and EIS). The individual and simultaneous determinations of EP and NEP were performed using square-wave voltammetry, yielding …
Acetylcholinesterase Immobilization On A Natural Thin Membrane For Stable Biocatalyst Design, Si̇nem Öztürk, Ceyhun Işik, Mustafa Teke
Acetylcholinesterase Immobilization On A Natural Thin Membrane For Stable Biocatalyst Design, Si̇nem Öztürk, Ceyhun Işik, Mustafa Teke
Turkish Journal of Chemistry
This study involved the immobilization of acetylcholinesterase (AChE) onto a natural thin membrane extracted from the inner epidermal layer of Allium cepa, with the aim of enhancing the enzyme’s stability, activity, and reusability for potential biotechnological applications. The membrane, composed of biocompatible polymers and naturally occurring functional groups, was used as a sustainable support in a combined strategy involving adsorption followed by glutaraldehyde-mediated cross-linking. Immobilization conditions were optimized by evaluating key factors such as enzyme concentration, membrane quantity, cross-linker dosage, and contact time to achieve maximal catalytic efficiency. Structural and morphological changes on the membrane surface were assessed via scanning …
Antifungal Activity Of Isolated Compounds From Centaurea Salicifolia Var. Salicifolia Against Candida Species, Including Multidrug-Resistant C. Auris, C. Inconspicua, And C. Dubliniensis, Seli̇n Tufan, Di̇lek Şatana, Nur Tan
Antifungal Activity Of Isolated Compounds From Centaurea Salicifolia Var. Salicifolia Against Candida Species, Including Multidrug-Resistant C. Auris, C. Inconspicua, And C. Dubliniensis, Seli̇n Tufan, Di̇lek Şatana, Nur Tan
Turkish Journal of Chemistry
Natural compounds obtained from plants have always held great potential for drug discovery and, as such, have drawn the attention of researchers as novel antifungal molecules that can be effective against fungal resistance. The antifungal activity of sesquiterpene lactones has been extensively investigated against various fungal strains, but there is limited data on their antifungal activity against Candida species. Sesquiterpene lactones are abundant in the Asteraceae family, and 90% of identified sesquiterpene lactones have been isolated from members of this family. Three extracts obtained from the aerial parts of Centaurea salicifolia var. salicifolia, which had not been investigated prior to …
Electrochemical Determination Of Terbutaline Using A Sno2 Nanoparticle-Modified Carbon Paste Electrode, Rauf Gulamov, Şenol Alpat, Si̇bel Kilinç Alpat
Electrochemical Determination Of Terbutaline Using A Sno2 Nanoparticle-Modified Carbon Paste Electrode, Rauf Gulamov, Şenol Alpat, Si̇bel Kilinç Alpat
Turkish Journal of Chemistry
Terbutaline hemisulfate (THS), a selective beta-2 agonist, is preferred as a bronchodilator for the treatment of asthma and bronchitis, as well as a tocolytic agent to delay labor in acute situations during premature birth. The use of beta-2 agonists above a certain dose is considered doping in sports competitions. Therefore, it is important that they be determined with high sensitivity and selectivity within a short analysis time. In this study, a SnO2 nanoparticle-modified carbon paste electrode was developed for the determination of THS. Cyclic voltammetry and differential pulse voltammetry were employed as electrochemical methods. The operating conditions of the developed …
Chitosan Microparticle-Based Antibacterial Nasal Barrier Formulation And In Vivo Evaluations, Güli̇z Ak, Ayça Erek, Tuğba Karakayali, Şadi̇ye Çeti̇n, Şenay Şanlier
Chitosan Microparticle-Based Antibacterial Nasal Barrier Formulation And In Vivo Evaluations, Güli̇z Ak, Ayça Erek, Tuğba Karakayali, Şadi̇ye Çeti̇n, Şenay Şanlier
Turkish Journal of Chemistry
Microorganisms remain a major cause of infectious diseases, emphasizing the need for alternative and complementary antimicrobial strategies. In this context, plant-derived materials have attracted increasing attention for their antimicrobial and protective properties. Chitosan, a biocompatible and cationic biopolymer, has emerged as an effective carrier system for encapsulating such plant-derived components. In this study, chitosan microparticles were prepared through ionic gelation followed by spray drying and loaded with thyme oil and olive leaf extract. The resulting microparticles exhibited an average size of approximately 1.8 μm and a total phenolic content of 23 mg GAE/g. These microparticles were incorporated into a glycerin–starch …
Toroidal Plasmonic Nanodimers For Enhanced Near-Infrared Emission In Heterostructured Inp Quantum Dots, Arda Gülücü, Emre Ozan Polat
Toroidal Plasmonic Nanodimers For Enhanced Near-Infrared Emission In Heterostructured Inp Quantum Dots, Arda Gülücü, Emre Ozan Polat
Turkish Journal of Physics
Near-infrared (NIR) emitters operating in the 650--900 nm spectral range are highly attractive for imaging and sensing in turbid media. However, cadmium-free InP-based quantum dots (QDs) often exhibit limited brightness owing to nonradiative recombination pathways and inefficient photon outcoupling. In particular, heterostructured InP QDs may possess band alignments that induce partial spatial separation of charge carriers, thereby reducing the electron-hole wavefunction overlap. This characteristic modifies the intrinsic recombination dynamics and increases the sensitivity of their emission to the surrounding photonic environment. Here, we investigate silver toroidal plasmonic nanoantenna dimers (Ag TPNDs) using finite-difference time-domain (FDTD) simulations as a geometry-tunable platform …
Radiation Pressure And Membrane Dynamics In Cavity Optomechanics: Interaction Hamiltonian And Quantization, Mahmut Can Özuygur
Radiation Pressure And Membrane Dynamics In Cavity Optomechanics: Interaction Hamiltonian And Quantization, Mahmut Can Özuygur
Turkish Journal of Physics
Cavity optomechanics explores the interaction between light confined in optical cavities and mechanical oscillators, primarily driven by radiation pressure forces. These interactions enable significant advances in precision measurements, quantum information processing, and tests of fundamental quantum mechanics. This paper presents a detailed analysis of membrane vibration and radiation pressure force within a cavity optomechanical system. The membrane's equation of motion is derived, the radiation pressure force is evaluated within the Lorentz force formalism, and the corresponding interaction Hamiltonian is formulated. Quantization of the resulting Hamiltonian enables the investigation of quantum phenomena, including entanglement generation and quantum state transfer, and provides …
Observational Constraints On The Structure-Induced Dark Energy Model, Ali̇ Kazim Çamlibel
Observational Constraints On The Structure-Induced Dark Energy Model, Ali̇ Kazim Çamlibel
Turkish Journal of Physics
A new phenomenological dark energy model, originally associated with large-scale structure formation and proposed as a solution to the fine-tuning and coincidence problems related to the cosmological constant, was analyzed within the framework of General Relativity in a Friedmann-Robertson-Walker spacetime and its model parameters were estimated using cosmic chronometers and recent DESI data. It turns out that the proposed model can serve as an alternative evolving dark energy model with a novel equation of state function. Given the form of this phenomenological energy density ansatz, which rises with the nonlinear structure growth in the universe and declines as cosmic voids …
The Effect Of Spin Polarization On Ion-Acoustic Solitary Waves In Quantum Plasmas, Amirhosein Rezvani, Sedigheh Miraboutalebi, Leila Rajaei, Mahmoodreza Sharifian
The Effect Of Spin Polarization On Ion-Acoustic Solitary Waves In Quantum Plasmas, Amirhosein Rezvani, Sedigheh Miraboutalebi, Leila Rajaei, Mahmoodreza Sharifian
Turkish Journal of Physics
The exchange interaction, a fundamentally quantum-mechanical phenomenon, can significantly modify the classical description of cold, overdense plasmas. These quantum effects can be systematically analyzed within the framework of quantum magnetohydrodynamic (QMHD) theory, which enables the use of separate momentum equations for spin-up and spin-down electron populations. In this study, we adopt this approach to incorporate exchange interactions for both spin species and investigate the excitation of ion-acoustic wave (IAW) solitons in the plasma system. Using a perturbative expansion method, the governing equations are reduced to a nonlinear Schrödinger equation (NLSE), which admits solitonic wave solutions. The stability of these solitons …
On Cosmological Equation Of State From The First Law Of Thermodynamics, Ch'ng Han Siong
On Cosmological Equation Of State From The First Law Of Thermodynamics, Ch'ng Han Siong
Turkish Journal of Physics
We derive several equations of state for different types of energy from the first law of thermodynamics. We derive the equation of state of a Machian universe from the well-known energy formulaE=mc2. This equation of state is consistent with previously reported results. We then propose hypothetical forms of energy that lead to the equations of state of the Chaplygin gas, generalized Chaplygin gas, and modified Chaplygin gas. We also obtain the energy density of the Chaplygin gas by dividing the hypothetical energy by the volume of the universe, and find that it is consistent with previously reported results. Finally, we …
Design And Fabrication Of Petri Dish Optimized For High-Frequency Acoustic Microscopy Using 3d Printing, Tuna Pesen, Beyza Ceren Eren, Arda İnanç, Bora Akgün
Design And Fabrication Of Petri Dish Optimized For High-Frequency Acoustic Microscopy Using 3d Printing, Tuna Pesen, Beyza Ceren Eren, Arda İnanç, Bora Akgün
Turkish Journal of Physics
High-frequency imaging in acoustic microscopy requires the use of Petri dishes with thin and acoustically transparent bottoms to minimize signal attenuation and distortion. Commercially available options suitable for this purpose are often expensive or limited in compatibility with custom setups. Here, we present a cost-effective and easily customizable alternative developed in our laboratory, consisting of a 3D-printed frame combined with commercially available stretch film. The stretch film serves as an ultrathin (8 µm thickness) base that supports efficient high-frequency acoustic transmission, enabling clear and reliable imaging. Beyond acoustic microscopy, the adaptable design is also compatible with other modalities such as …
Biharmonic Curves In Warped Product Manifolds I ×FMN(C), Şaban Güvenç, Ci̇han Özgür
Biharmonic Curves In Warped Product Manifolds I ×FMN(C), Şaban Güvenç, Ci̇han Özgür
Turkish Journal of Mathematics
We explore the geometric properties of biharmonic curves in warped product manifolds of the form I ×f Mn(c), where I is an open interval and Mn(c) is a space of constant curvature. By establishing a main theorem, we analyze four distinct cases to reveal deeper curvature-related characteristics of these curves, including situations where they are slant. Finally, we construct three examples in I ×f S2(1).
Generalized Submaximality And Paracompactness In Ideal Topological Spaces Via Δβ*-𝔍-Open Sets, Chawalit Boonpok, Areeyuth Sama-Ae
Generalized Submaximality And Paracompactness In Ideal Topological Spaces Via Δβ*-𝔍-Open Sets, Chawalit Boonpok, Areeyuth Sama-Ae
Turkish Journal of Mathematics
This paper explores the notions of δβ*-𝔍-submaximality and δβ*-𝔍-paracompactness within ideal topological spaces, viewing them as natural generalizations of the traditional concepts of submaximality and paracompactness. These concepts arise naturally in the context of ideal topology, where an ideal 𝔍 on a topological space provides additional structure for analyzing topological properties. It focuses on the study of submaximal spaces by employing δβ*-𝔍-open sets, which serve as fundamental building blocks for understanding the topological behavior in ideal spaces. Furthermore, the work provides multiple characterizations of δβ*-𝔍-paracompact spaces and examines how this property behaves …