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Articles 61 - 90 of 10244
Full-Text Articles in Physical Sciences and Mathematics
Structure-Activity Relationship Of Anticancer Drug Candidate Quinones, Nadire Özenver, Neslihan Sönmez, Merve Yüzbaşıoğlu Baran, Ayşe Uz, Lütfiye Ömür Demi̇rezer
Structure-Activity Relationship Of Anticancer Drug Candidate Quinones, Nadire Özenver, Neslihan Sönmez, Merve Yüzbaşıoğlu Baran, Ayşe Uz, Lütfiye Ömür Demi̇rezer
Turkish Journal of Chemistry
Breast cancer is one of the most prevalent cancer types worldwide. Chemotherapy is a substantial approach in the management of breast cancer despite the occurrence of chemotherapy-associated side effects and the development of multidrug resistance in cancer cells. At this point, a variety of quinone derivatives may represent potential as possible anticancer drug candidates due to possessing structural similarity towards clinically used anticancer drugs like doxorubicin. Therefore, we investigated the cytotoxic effects of various quinone derivatives with structural diversity towards a variety of breast cancer cells. We further determined their toxicity in healthy cells to evaluate their drug capability potential. …
Detection And Characterization Of The Pichia Manshurica Biofilm On The Traditionally Produced Homemade Apple Vinegar, Zeynep İşlek Koklu, Pınar Akkuş Süt, Esra Eskihoran Üçüncüoğlu, Sadık Kalayci, Fikrettin Şahi̇n
Detection And Characterization Of The Pichia Manshurica Biofilm On The Traditionally Produced Homemade Apple Vinegar, Zeynep İşlek Koklu, Pınar Akkuş Süt, Esra Eskihoran Üçüncüoğlu, Sadık Kalayci, Fikrettin Şahi̇n
Turkish Journal of Chemistry
Pichia yeasts are capable of forming biofilms during vinegar production and causing spoilage in various beverages. In addition, there exists a significant likelihood of encountering yeast contamination which can prevent vinegar production. The present study investigates the detection and characterization of the Pichia manshurica (P. manshurica) biofilm on traditionally produced homemade apple vinegar. The unique characteristics of vinegar were analyzed with a focus on the constituent, known as the “mother of vinegar”, whose composition is comprised of cellulosic biofilm and acetic acid bacteria, including Gluconobacter oxydans (G. oxydans) Briefly, P. manshurica was isolated from apple vinegar and characterized in terms …
Chromium Speciation In Water Using Magnetic Polyaniline Nanoparticles Coupled With Microsampling Injection-Flame Atomic Absorption Spectroscopy, Osman Çaylak
Turkish Journal of Chemistry
The chromium speciation procedure was optimized using magnetic polyaniline nanoparticles (Fe3O4@PANI NPs) solid-phase extraction coupled with microsampling injection-flame atomic absorption spectrometry (MIS-FAAS). Chromium speciation was successfully achieved by Fe3O4@PANI NPs at pH 8.0. The recoveries obtained for Cr(III) and Cr(VI) were above 95% and under 5%, respectively. Recoveries of over 95% for Cr(III) from 40.0 mL of the sample were obtained using 25 mg Fe3O4@PANI NPs and 500 µL of 0.2% (w/v) thiourea (TU) solution prepared in 2 mol L–1 HCl as eluent. Total chromium as Cr(III) was extracted quantitatively after reducing the Cr(VI) to Cr(III). The linear range, detection …
The Effect Of Partial Substitution Of Noble Metal (Pd) At The B Site Of La0.6sr0.4feo3 As A Supercapacitor Electrode Material, Nagihan Deli̇baş, Turgut Süleymanoğlu
The Effect Of Partial Substitution Of Noble Metal (Pd) At The B Site Of La0.6sr0.4feo3 As A Supercapacitor Electrode Material, Nagihan Deli̇baş, Turgut Süleymanoğlu
Turkish Journal of Chemistry
Sol-gel combustion was used to produce the perovskite-type La0.6Sr0.4FeO3 (LSF) and La0.6Sr0.4Fe0.9Pd0.1O3 (LSFP) materials and assessed as supercapacitor electrodes. The synthesized materials’ crystal structure, morphology, and electrochemical performance were thoroughly analyzed. The partial substitution of Pd in the B site of the LSF structure affected the electrochemical properties of this compound and improved its performance. In fact, the greatest effect of Pd substitution was on the content of oxygen vacancies, which are known as the active sites of the perovskite surface in the supercapacitor cell. The specific capacitance obtained for the sample containing Pd was about 80 F.g–1 at a …
Hydroxyl- Terminated Dendrimers With Sulfonimide Linkers As Binders For Metals Of Industrial Significance, Khaleel Abu Sbeih, Mohammad Al Harahsheh
Hydroxyl- Terminated Dendrimers With Sulfonimide Linkers As Binders For Metals Of Industrial Significance, Khaleel Abu Sbeih, Mohammad Al Harahsheh
Turkish Journal of Chemistry
First- and second-generation hydroxyl- terminated dendrimers were prepared starting from a 1,3-diaminopropane core and sulfonimide linkers. A first-generation mesitylene-derived dendrimer was also prepared with the same terminals. The dendrimers were then reacted with Fe3+, Al3+, and UO22+ separately in order to apply the dendrimers for binding these metals, which have important industrial applications and pose environmental problems simultaneously. The prepared dendrimers were also shown to bind Fe3+ selectively from mixtures with Al3+.
Copolymerization Of Pyrrole And Carbazole Onto Polyester Textile, Mehmet Akif Küçükkaya, Utku Ustamehmetoğlu, Esma Sezer, Belkıs Ustamehmetoğlu
Copolymerization Of Pyrrole And Carbazole Onto Polyester Textile, Mehmet Akif Küçükkaya, Utku Ustamehmetoğlu, Esma Sezer, Belkıs Ustamehmetoğlu
Turkish Journal of Chemistry
The purpose of this study was the polymerization of carbazole (Cz), pyrrole (Py) and copolymerization of them onto polyester (PES) textile with chemical oxidative method by using FeCl3. First, in order to determine the optimum conditions, the effect of polymerization steps, the immersion order of the PES to the oxidant and monomer solutions, time, monomer, oxidant, and surfactant concentrations and types on the conductivities of PES/PCz composite were investigated and at this conditions, conductive composite, PES/P[Py-co-Cz] was obtained. The highest conductivities were obtained as 12.4 mS/cm and 9.0 mS/cm for PES/PCz and PES/P[Py-co-Cz], respectively. Further characterization of PES/P[Py-co-Cz] was performed …
Nonoxidative Dehydrogenation Of Propane Using Boron-Incorporated Silica-Supported Pt Sites Synthesized By Atomic Layer Deposition, Gokhan Çeli̇k
Nonoxidative Dehydrogenation Of Propane Using Boron-Incorporated Silica-Supported Pt Sites Synthesized By Atomic Layer Deposition, Gokhan Çeli̇k
Turkish Journal of Chemistry
Nonoxidative dehydrogenation of propane to propylene using Pt-based supported catalysts is an active research area in catalysis because catalyst attributes of Pt sites can be controlled by careful design of active sites. One way to achieve this is by the addition of a second metal that may impart a change in the electron density of active sites, which in turn affects catalytic performance. In this study, bimetallic Pt and B sites were deposited on powder SiO2 using atomic layer deposition (ALD). Boron was first deposited on SiO2 via half-cycle ALD using triisoproplyborate as the B source. Following calcination, Pt deposition …
An Efficient One-Pot And Simple Multicomponent Approach To The Synthesis Of Highly Functionalized Furans Containing Dialkyl Phenol, Fourogh Jalili Milani, Mahmoud Nassiri, Jaber Salehzadeh
An Efficient One-Pot And Simple Multicomponent Approach To The Synthesis Of Highly Functionalized Furans Containing Dialkyl Phenol, Fourogh Jalili Milani, Mahmoud Nassiri, Jaber Salehzadeh
Turkish Journal of Chemistry
In this study, arylglyoxals, acetylacetone, and 2,6-dimethyl phenol or 2,6-di-tert-butyl phenol are combined to efficiently synthesize a series of 1-(4-(3,5-dialkylphenyl)-2-methyl-5-phenylfuran-3-yl) ethan-1-one derivatives in excellent yields. These reactions were carried out in acetone at reflux under catalyst-free conditions in the presence of triethylamine as a base for 3 h. NMR, FT-IR, EI-MS, and elemental studies were used to characterize the products' structural characteristics. The present study has also several benefits, such as excellent yields and the ease of workup procedure, making it an appealing, practical, and acceptable one-pot method for producing functionalized derivatives of dialkyl furan.
Voltammetric Measurement Of Catechol-O-Methyltransferase Inhibitor Tolcapone In The Pharmaceutical Form On The Boron-Doped Diamond Electrode, Musa Kiran, Yavuz Yardim
Voltammetric Measurement Of Catechol-O-Methyltransferase Inhibitor Tolcapone In The Pharmaceutical Form On The Boron-Doped Diamond Electrode, Musa Kiran, Yavuz Yardim
Turkish Journal of Chemistry
This study presents an electroanalytical approach to measure the catechol-O-methyltransferase (COMT) inhibitor tolcapone (TOL) using a boron-doped diamond (BDD) electrode. The application of cyclic voltammetry (CV) technique revealed that TOL exhibited a distinct, diffusion-controlled, irreversible anodic peak at a potential of approximately +0.71 V (vs. Ag/AgCl) in a 0.1 mol L–1 phosphate buffer solution (PBS) with a pH of 2.5. The oxidation of TOL is highly dependent on the pH and supporting electrolytes. Based on the data obtained from the pH investigation, a proposed mechanism for the electro-oxidation of TOL is suggested. Using the square wave voltammetry (SWV) technique, a …
Optimized Intermediate Layer Formation And Electroless Plating Methods To Obtain Supported Dense Pd Surfaces, Gamze Gümüşlü Gür, Berna Toprak
Optimized Intermediate Layer Formation And Electroless Plating Methods To Obtain Supported Dense Pd Surfaces, Gamze Gümüşlü Gür, Berna Toprak
Turkish Journal of Chemistry
Dense metallic membranes, especially Pd and Pd alloys, have been intensely investigated to provide an alternative and economical way to obtain H2 with ultrahigh purity. To overcome the high cost of Pd, composite membrane structures that comprise a thin layer of Pd are utilized. However, it is a challenge to obtain a thin, dense, and uniform Pd layer on the support materials. This study investigates the parametric analysis of γ-Al2O3 interlayer formation and the electroless Pd plating (Pd ELP) procedures on α-Al2O3 supports with the aim to achieve a thin, uniform Pd surface without annealing. Adjustments in PEG/PVA concentration, dipping …
Low Fine-Tuning With Heavy Higgsinos In Yukawa Unified Susy Guts, Cem Salih Ün
Low Fine-Tuning With Heavy Higgsinos In Yukawa Unified Susy Guts, Cem Salih Ün
Turkish Journal of Physics
The work presented considers a class of minimally constructed Yukawa unified SUSY GUTs - NUHM2 - and explores their implications when their soft supersymmetry breaking Lagrangian is generalized by the nonholomorphic terms which provide extra contributions to the Higgsino mass and couple the supersymmetric scalar fields to the wrong Higgs doublets. With such a simple extension, it can be found several regions with interesting implications which cannot be realized in the usual restricted models. It is observed that the Yukawa unification solutions can be compatible with a relatively light mass spectrum and acceptable low fine-tuning measurements. In the restricted models …
Motion Magnification-Inspired Feature Manipulation For Deepfake Detection, Aydamir Mirzayev, Hamdi Di̇bekli̇oğlu
Motion Magnification-Inspired Feature Manipulation For Deepfake Detection, Aydamir Mirzayev, Hamdi Di̇bekli̇oğlu
Turkish Journal of Electrical Engineering and Computer Sciences
Recent advances in deep learning, increased availability of large-scale datasets, and improvement of accelerated graphics processing units facilitated creation of an unprecedented amount of synthetically generated media content with impressive visual quality. Although such technology is used predominantly for entertainment, there is widespread practice of using deepfake technology for malevolent ends. This potential for malicious use necessitates the creation of detection methods capable of reliably distinguishing manipulated video content. In this work we aim to create a learning-based detection method for synthetically generated videos. To this end, we attempt to detect spatiotemporal inconsistencies by leveraging a learning-based magnification-inspired feature manipulation …
Error Performance Enhancement And Complexity Reduction In Ofdm Systems Via Coordinate Interleaving Under Practical Impairments, Mustafa Anıl Reşat, Armed Tusha, Seda Doğan Tusha, Serdar Özyurt, Hüseyin Arslan
Error Performance Enhancement And Complexity Reduction In Ofdm Systems Via Coordinate Interleaving Under Practical Impairments, Mustafa Anıl Reşat, Armed Tusha, Seda Doğan Tusha, Serdar Özyurt, Hüseyin Arslan
Turkish Journal of Electrical Engineering and Computer Sciences
In this work, subcarrier coordinate interleaving (CI) is implemented to orthogonal frequency division multiplexing (OFDM) systems with the aim of both enhancing the error performance and reducing the implementation complexity. To this end, the modulated symbols are independently chosen from a modified M-ary amplitude-shift keying signal constellation under a specific CI strategy. In addition to doubling the diversity level of the original OFDM scheme, the adopted CI approach also drastically reduces the inverse fast Fourier transform (IFFT) size at the transmit side by guaranteeing the first half of the input vector to be identical with the second half at the …
Longitudinal Attacks Against Iterative Data Collection With Local Differential Privacy, Mehmet Emre Gürsoy
Longitudinal Attacks Against Iterative Data Collection With Local Differential Privacy, Mehmet Emre Gürsoy
Turkish Journal of Electrical Engineering and Computer Sciences
Local differential privacy (LDP) has recently emerged as an accepted standard for privacy-preserving collection of users’ data from smartphones and IoT devices. In many practical scenarios, users’ data needs to be collected repeatedly across multiple iterations. In such cases, although each collection satisfies LDP individually by itself, a longitudinal collection of multiple responses from the same user degrades that user’s privacy. To demonstrate this claim, in this paper, we propose longitudinal attacks against iterative data collection with LDP. We formulate a general Bayesian adversary model, and then individually show the application of this adversary model on six popular LDP protocols: …
A Novel Extended Reaction Force/Torque Observer With Impedance Control, İlkay Turaç Özçeli̇k, Abdurrahman Eray Baran
A Novel Extended Reaction Force/Torque Observer With Impedance Control, İlkay Turaç Özçeli̇k, Abdurrahman Eray Baran
Turkish Journal of Electrical Engineering and Computer Sciences
This paper proposes a new extended version of the reaction force observer (RFOB) for high-precision motion control systems. The RFOB has been proven to be useful for many applications in the literature. However, because of the low-pass filter present inside of the RFOB, it has certain limitations. In this study, a new algorithm is proposed to compensate for filtering-based errors in the classical RFOB structure. The algorithm includes the differentiation of the observed force and scaling with a proper value. However, since the force has a noisy nature, differentiation also affects the signal’s stability and performance. To resolve this issue, …
Differentially Private Online Bayesian Estimation With Adaptive Truncation, Sinan Yildirim
Differentially Private Online Bayesian Estimation With Adaptive Truncation, Sinan Yildirim
Turkish Journal of Electrical Engineering and Computer Sciences
In this paper, a novel online and adaptive truncation method is proposed for differentially private Bayesian online estimation of a static parameter regarding a population. A local differential privacy setting is assumed where sensitive information from individuals is collected on an individual level and sequentially. The inferential aim is to estimate, on the fly, a static parameter regarding the population to which those individuals belong. We propose sequential Monte Carlo to perform online Bayesian estimation. When individuals provide sensitive information in response to a query, it is necessary to corrupt it with privacy-preserving noise to ensure the privacy of those …
Traffic Signal Optimization Using Multiobjective Linear Programming For Oversaturated Traffic Conditions, Mustafa Murat Coşkun, Cevat Şener, İsmail Hakkı Toroslu
Traffic Signal Optimization Using Multiobjective Linear Programming For Oversaturated Traffic Conditions, Mustafa Murat Coşkun, Cevat Şener, İsmail Hakkı Toroslu
Turkish Journal of Electrical Engineering and Computer Sciences
In this study, we present a framework designed to optimize signals at intersections experiencing oversaturated traffic conditions, utilizing mixed-integer linear programming (MILP) techniques. The proposed MILP solutions were developed with different objective functions, namely a reduction in the total remaining queue and fair distribution of the remaining queue after each signal cycle. Our framework contains two distinct stages. The initial stage applies two distinct MILP methodologies, while the subsequent stage employs a neighborhood search method to further reduce the delays associated with the green signal timings derived from the first stage. Ultimately, to evaluate their effectiveness across various intersections, we …
Artificial Intelligence-Based Evaluation Of The Factors Affecting The Sales Of An Iron And Steel Company, Mehmet Pekkaya, Zafer Uysal, Aytaç Altan, Seçkin Karasu
Artificial Intelligence-Based Evaluation Of The Factors Affecting The Sales Of An Iron And Steel Company, Mehmet Pekkaya, Zafer Uysal, Aytaç Altan, Seçkin Karasu
Turkish Journal of Electrical Engineering and Computer Sciences
It is important to predict the sales of an iron and steel company and to identify the variables that influence these sales for future planning. The aim in this study was to identify and model the key factors that influence the sales volume of an iron and steel company using artificial neural networks (ANNs). We attempted to obtain an integrated result from the performance/sales levels of 5 models, to use the ANN approach with hybrid algorithms, and also to present an exemplary application in the base metals industry, where there is a limited number of studies. This study contributes to …
Fast Grid Search: A Grid Search-Inspired Algorithm For Optimizing Hyperparameters Of Support Vector Regression, Mustafa Açikkar
Fast Grid Search: A Grid Search-Inspired Algorithm For Optimizing Hyperparameters Of Support Vector Regression, Mustafa Açikkar
Turkish Journal of Electrical Engineering and Computer Sciences
This study presents a fast hyperparameter optimization algorithm based on the benefits and shortcomings of the standard grid search (GS) algorithm for support vector regression (SVR). This presented GS-inspired algorithm, called fast grid search (FGS), was tested on benchmark datasets, and the impact of FGS on prediction accuracy was primarily compared with the GS algorithm on which it is based. To validate the efficacy of the proposed algorithm and conduct a comprehensive comparison, two additional hyperparameter optimization techniques, namely particle swarm optimization and Bayesian optimization, were also employed in the development of models on the given datasets. The evaluation of …
Machine Learning Approaches In Comparative Studies For Alzheimer’S Diagnosis Using 2d Mri Slices, Zhen Zhao, Joon Huang Chuah, Chee-Onn Chow, Kaijian Xia, Yee Kai Tee, Yan Chai Hum, Khin Wee Lai
Machine Learning Approaches In Comparative Studies For Alzheimer’S Diagnosis Using 2d Mri Slices, Zhen Zhao, Joon Huang Chuah, Chee-Onn Chow, Kaijian Xia, Yee Kai Tee, Yan Chai Hum, Khin Wee Lai
Turkish Journal of Electrical Engineering and Computer Sciences
Alzheimer’s disease (AD) is an illness that involves a gradual and irreversible degeneration of the brain. It is crucial to establish a precise diagnosis of AD early on in order to enable prompt therapies and prevent further deterioration. Researchers are currently focusing increasing attention on investigating the potential of machine learning techniques to simplify the automated diagnosis of AD using neuroimaging. The present study involved a comparison of models for the detection of AD through the utilization of 2D image slices obtained from magnetic resonance imaging brain scans. Five models, namely ResNet, ConvNeXt, CaiT, Swin Transformer, and CVT, were implemented …
Fractional Delay-Dependent Load Frequency Controller Design For A Single-Area Power System With Communication Delay, Erhan Yumuk
Fractional Delay-Dependent Load Frequency Controller Design For A Single-Area Power System With Communication Delay, Erhan Yumuk
Turkish Journal of Electrical Engineering and Computer Sciences
This paper proposes a fractional delay-dependent load frequency control design approach for a single-area power system with communication delay based on gain and phase margin specifications. In this approach, the closed-loop reference transfer function relies on the delayed Bode’s transfer function. The gain and phase margin specifications are established in order to optimize the reference model based on three time-domain performance indices. Here, a category of fractional-order model is employed to describe the single-area power system incorporating communication delay. The controller parameters are determined using the fractional-order system model and optimal closed-loop reference model. Then, a delay-dependent control mechanism is …
Grey Wolf Optimization Algorithm-Based Robust Neural Learning Control Of Passive Torque Simulators With Predetermined Performance, Seyyed Amirhossein Saadat, Mohammad Mehdi Fateh, Javad Keighobadi
Grey Wolf Optimization Algorithm-Based Robust Neural Learning Control Of Passive Torque Simulators With Predetermined Performance, Seyyed Amirhossein Saadat, Mohammad Mehdi Fateh, Javad Keighobadi
Turkish Journal of Electrical Engineering and Computer Sciences
In flight control systems, the actuators need to tolerate aerodynamic torques and continue their operations without interruption. To this end, using the simulators to test the actuators in conditions close to the real flight is efficient. On the other hand, achieving the guaranteed performance encounters some challenges and practical limitations such as unknown dynamics, external disturbances, and state constraints in reality. Thus, this article attempts to present a robust adaptive neural network learning controller equipped with a disturbance observer for passive torque simulators (PTS) with load torque constraints. The radial basis function networks (RBFNs) are employed to identify the unknown …
Milp Modeling Of Matrix Multiplication: Cryptanalysis Of Klein And Prince, Murat Burhan İlter, Ali Aydın Selçuk
Milp Modeling Of Matrix Multiplication: Cryptanalysis Of Klein And Prince, Murat Burhan İlter, Ali Aydın Selçuk
Turkish Journal of Electrical Engineering and Computer Sciences
Mixed-integer linear programming (MILP) techniques are widely used in cryptanalysis, aiding in the discovery of optimal linear and differential characteristics. This paper delves into the analysis of block ciphers KLEIN and PRINCE using MILP, specifically calculating the best linear and differential characteristics for reduced-round versions. Both ciphers employ matrix multiplication in their diffusion layers, which we model using multiple XOR operations. To this end, we propose two novel MILP models for multiple XOR operations, which use fewer variables and constraints, proving to be more efficient than standard methods for XOR modeling. For differential cryptanalysis, we identify characteristics with a probability …
Automated Identification Of Vehicles In Very High-Resolution Uav Orthomosaics Using Yolov7 Deep Learning Model, Esra Yildirim, Umut Güneş Seferci̇k, Taşkın Kavzoğlu
Automated Identification Of Vehicles In Very High-Resolution Uav Orthomosaics Using Yolov7 Deep Learning Model, Esra Yildirim, Umut Güneş Seferci̇k, Taşkın Kavzoğlu
Turkish Journal of Electrical Engineering and Computer Sciences
The utilization of remote sensing products for vehicle detection through deep learning has gained immense popularity, especially due to the advancement of unmanned aerial vehicles (UAVs). UAVs offer millimeter-level spatial resolution at low flight altitudes, which surpasses traditional airborne platforms. Detecting vehicles from very high-resolution UAV data is crucial in numerous applications, including parking lot and highway management, traffic monitoring, search and rescue missions, and military operations. Obtaining UAV data at desired periods allows the detection and tracking of target objects even several times during a day. Despite challenges such as diverse vehicle characteristics, traffic congestion, and hardware limitations, the …
Some Estimates On The Spin−Submanifolds, Serhan Eker
Some Estimates On The Spin−Submanifolds, Serhan Eker
Turkish Journal of Mathematics
In this paper, an optimal lower bound is given for the Submanifold Dirac operator in terms of the trace of an Energy−Momentum tensor, scalar curvature and mean curvature. In the equality case, it is proven that the submanifold is Einstein if the normal bundle is flat. Key words: Spin geometry, eigenvalues,
On The Qualitative Analysis Of Nonlinear Q-Fractional Delay Descriptor Systems, Abdullah Yi̇ği̇t
On The Qualitative Analysis Of Nonlinear Q-Fractional Delay Descriptor Systems, Abdullah Yi̇ği̇t
Turkish Journal of Mathematics
In this manuscript, we obtain some sufficient conditions for a nonlinear q fractional integro singular system with constant delays to be asymptotically admissible and a nonlinear q fractional non-singular system to be asymptotically stable. We use Lyapunov-Krasovskii functionals and some inequalities to obtain these conditions. At the same time, we present some numerical examples that confirm the sufficient conditions we obtained theoretically, with their annotated solutions and graphs.
Invariant Symplectic Forms On Number Fields, Ahmad Rafiqi, Ayberk Zeyti̇n
Invariant Symplectic Forms On Number Fields, Ahmad Rafiqi, Ayberk Zeyti̇n
Turkish Journal of Mathematics
We show that a number field of the form Q(λ) admits a symplectic form which is invariant under multiplication by λ if and only if the minimal polynomial of λ is palindromic of even degree. In particular, if λ is an algebraic integer, it is forced to be a unit. In the case when the minimal polynomial of λ is palindromic of degree 2d, we show that there is a d-dimensional space of invariant symplectic forms on Q(λ) .
On The Invariance Of Hyperstoneanness Under Lattice Isomorphisms, Banu Güntürk
On The Invariance Of Hyperstoneanness Under Lattice Isomorphisms, Banu Güntürk
Turkish Journal of Mathematics
Let X and Y be compact Hausdorff spaces with Y hyperstonean. In this paper, we prove that if C(X,R) and C(Y,R) are lattice isomorphic then these Banach spaces are linearly isometric, and, consequently, X and Y are homeomorphic, which in turn implies that X is also hyperstonean. Actually, we prove more than what is announced in the headline above. This result, in some ways, is a generalization of the well-known Banach-Stone theorem.
On Strong Solvability Of One Nonlocal Boundary Value Problem For Laplace Equation In Rectangle, Telman Gasymov, Baharchin Akhmadli, Ümi̇t Ildiz
On Strong Solvability Of One Nonlocal Boundary Value Problem For Laplace Equation In Rectangle, Telman Gasymov, Baharchin Akhmadli, Ümi̇t Ildiz
Turkish Journal of Mathematics
One nonlocal boundary value problem for the Laplace equation in a bounded domain is considered in this work. The concept of a strong solution to this problem is introduced. The correct solvability of this problem in the Sobolev spaces generated by the weighted mixed norm is proved by the Fourier method. In a classic statement, this problem has been
Extremal Functions For A Singular Super-Critical Trudinger-Moser Inequality, Juan Zhao
Extremal Functions For A Singular Super-Critical Trudinger-Moser Inequality, Juan Zhao
Turkish Journal of Mathematics
In this paper, we deal with a singular super-critical Trudinger-Moser inequality on a unit ball of Rn , n ≥ 3. For any p > 1, we set λp(B) = inf u∈W1,n 0 (B),u̸≡0 ∫ B |∇u|ndx ( ∫ B |u|pdx)n/p as an eigenvalue related to the n-Laplacian. Let S be a set of radially symmetric functions. Precisely, if β ≥ 0 and α < (1 + p nβ)n−1+n/pλp(B) , then there exists a positive constant ϵ0 such that when λ ≤ 1 + ϵ0 , sup u∈W1,n 0 (B)∩S, ∫ B |∇u|ndx−α( ∫ B |u|p|x|pβdx) np ≤1 ∫ B |x|pβ ( eαn(1+ p n β)|u| n n−1 − λ Σm k=0 |αn(1 + p nβ)u n n−1 |k k! ) dx is attained, where αn = nω1/(n−1) n−1 , ωn−1 is the surface area of the unit ball in Rn . The proof is based on the method of blow-up analysis. The case λ = 0 was studied by Yang-Zhu in [38]. de Figueiredo [11] considered the case p = 2, β ≥ 0, and α = 0 in two dimension. The case λ = 0, p = n,−1 < β < 0, and α = 0 was considered by Adimurthi-Sandeep [1]. Our results extend those of the above cases.