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Full-Text Articles in Physical Sciences and Mathematics

Modules Over Invertible 1-Cocycles, José Manuel Fernández Vilaboa, Ramon Gonzalez Rodriguez, Brais Ramos Pérez, Ana Belén Rodríguez Raposo Mar 2024

Modules Over Invertible 1-Cocycles, José Manuel Fernández Vilaboa, Ramon Gonzalez Rodriguez, Brais Ramos Pérez, Ana Belén Rodríguez Raposo

Turkish Journal of Mathematics

In this paper, we introduce in a braided setting the notion of left module for an invertible 1-cocycle and we prove some categorical equivalences between categories of modules associated to an invertible 1-cocycle and categories of modules associated to Hopf braces.


Qualitative Results For A Generalized 2-Component Camassa-Holm System With Weak Dissipation Term, Nurhan Dündar Mar 2024

Qualitative Results For A Generalized 2-Component Camassa-Holm System With Weak Dissipation Term, Nurhan Dündar

Turkish Journal of Mathematics

Our main aim in the current study is to examine the mathematical properties of a generalized 2-component Camassa-Holm system with a weakly dissipative term. Firstly, we acquire the theorem of well-posedness in locally for the generalized system with weak dissipation. Then, we demonstrate that this system can reveal the blow-up phenomenon. Finally, we acquire the theorem of global existence utilizing a method of the Lyapunov function.


Isometries Of Length 1 In Purely Loxodromic Free Kleinian Groups And Trace Inequalities, İlker Savaş Yüce, Ahmet Nedi̇m Narman Mar 2024

Isometries Of Length 1 In Purely Loxodromic Free Kleinian Groups And Trace Inequalities, İlker Savaş Yüce, Ahmet Nedi̇m Narman

Turkish Journal of Mathematics

In this paper, we prove a generalization of a discreteness criteria for a large class of subgroups of PSL2(C) . In particular, given a finitely generated purely loxodromic free Kleinian group Γ = ⟨ξ1, ξ2, . . . , ξn⟩ for n ≥ 2, we show that |trace2(ξi) − 4| + |trace(ξiξjξ −1 i ξ −1 j ) − 2| ≥ 2 sinh2 ( 1 4 log αn ) for some ξi and ξj for i ̸= j in Γ provided that certain conditions on the hyperbolic displacements given by ξi , ξj and their length 3 conjugates formed by …


On The Reconstruction Of An Integro-Differential Dirac Operator With Parameter-Dependent Nonlocal Integral Boundary Conditions From The Nodal Data, Baki Keskin, Yu Ping Wang Mar 2024

On The Reconstruction Of An Integro-Differential Dirac Operator With Parameter-Dependent Nonlocal Integral Boundary Conditions From The Nodal Data, Baki Keskin, Yu Ping Wang

Turkish Journal of Mathematics

We consider the integro-differential Dirac operator with parameter-dependent nonlocal integral boundary conditions. We derive the asymptotic expressions for the eigenvalues and the zeros of eigenfunctions (nodal points or nodes) and develop a constructive procedure for solving the inverse nodal problem for this operator.


Timelike Surfaces With Parallel Normalized Mean Curvature Vector Field In The Minkowski 4-Space, Victoria Bencheva, Velichka Milousheva Mar 2024

Timelike Surfaces With Parallel Normalized Mean Curvature Vector Field In The Minkowski 4-Space, Victoria Bencheva, Velichka Milousheva

Turkish Journal of Mathematics

In the present paper, we study timelike surfaces with parallel normalized mean curvature vector field in the four-dimensional Minkowski space. We introduce special isotropic parameters on each such surface, which we call canonical parameters, and prove a fundamental existence and uniqueness theorem stating that each timelike surface with parallel normalized mean curvature vector field is determined up to a rigid motion in the Minkowski space by three geometric functions satisfying a system of three partial differential equations. In this way, we minimize the number of functions and the number of partial differential equations determining the surface, thus solving the Lund-Regge …


Recent Advances And Applications Of Nanostructured Membranes In Water Purification, Didem Aydin, İlkay Hilal Gübbük, Mustafa Ersöz Feb 2024

Recent Advances And Applications Of Nanostructured Membranes In Water Purification, Didem Aydin, İlkay Hilal Gübbük, Mustafa Ersöz

Turkish Journal of Chemistry

In recent years, water pollution caused by hazardous materials such as metals, drugs, pesticides, and insecticides has become a very serious environmental and health problem that needs to be addressed urgently. The nutritional needs associated with the increasing population also increase the demand for water use and rapidly increase the rate of freshwater consumption. Since most of the water in the universe is in the form of sea water, which cannot be directly used, freshwater resources are limited ,compared to the existing available water. When addressing the purification of all kinds of pollution in environmental research, nanostructured membranes attract attention …


Chromium Speciation In Water Using Magnetic Polyaniline Nanoparticles Coupled With Microsampling Injection-Flame Atomic Absorption Spectroscopy, Osman Çaylak Feb 2024

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 Feb 2024

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 …


N-(2-Aminobenzoyl)Benzotriazole Mediated Synthesis Of 3- Acyl-2-Alkyl(Aryl)-4-Hydroxyquinolines And 3-Acylamino-4(3h) Quinazolinones, İlbilge Merve Şenol, Sevtem Gökbulut Satioğlu, İlhami Çeli̇k Feb 2024

N-(2-Aminobenzoyl)Benzotriazole Mediated Synthesis Of 3- Acyl-2-Alkyl(Aryl)-4-Hydroxyquinolines And 3-Acylamino-4(3h) Quinazolinones, İlbilge Merve Şenol, Sevtem Gökbulut Satioğlu, İlhami Çeli̇k

Turkish Journal of Chemistry

New methods have been developed for the synthesis of the substituted quinolines and quinazolinones derivatives by utilizing N-(2-aminobenzoyl)benzotriazoles under mild reaction conditions. 3-Acyl-2-alkyl(aryl)-4-hydroxyquinolines were obtained in modarete yields by the reaction of N-(2-aminobenzoyl)benzotriazoles and diketones in the presence of tert-BuOK. 3-Acylamino-4(3H) quinazolinones were obtained in good yields via N-(2-aminobenzoyl)benzotriazoles, orthoester and hyrazides in one-pot.


Low Fine-Tuning With Heavy Higgsinos In Yukawa Unified Susy Guts, Cem Salih Ün Feb 2024

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 …


Reheating Constraints To Palatini Coleman-Weinberg Inflation, Nilay Bostan Feb 2024

Reheating Constraints To Palatini Coleman-Weinberg Inflation, Nilay Bostan

Turkish Journal of Physics

In this work, we examine the reheating constraints to symmetry-breaking mechanism, which is associated with Coleman-Weinberg inflation in the early universe. We consider the Coleman-Weinberg inflation potential, where the inflaton has a v ̸= 0 after inflation. Setting Treh = 105 GeV, we first show wreh dependency on ns , r , and N∗ for AV case. Then, we demonstrate the results of ns , r , N∗ , α = dns/d ln k for different reheating temperatures and compare the results with the latest BICEP/Keck data. We also present that ns −r and ns −N∗ planes and the effect …


Sustainable Bio-Based Solid Phase Extraction Adsorbent For The Determination Of Various Types Of Organic Compounds, Mustafa Zafer Ozel, James H. Clark, Avtar S. Matharu Feb 2024

Sustainable Bio-Based Solid Phase Extraction Adsorbent For The Determination Of Various Types Of Organic Compounds, Mustafa Zafer Ozel, James H. Clark, Avtar S. Matharu

Turkish Journal of Chemistry

A sustainable, bio-based, mesoporous material, Starbon A800, was explored for use as an adsorbent in solid phase extraction (SPE). A solution containing seven nitrosamines was first used as a standard to optimise conditions for extraction efficiency with Starbon A800. After optimising conditions, 25 compounds of varying polarity (terpenes, phenolics, pesticides, PAHs, amines, and nitrosamines) were extracted with SPE using either Starbon® A800, C18 or Porous Graphitic Carbon (PGC) as the adsorbent, for comparison purposes. At the same time, 3 different elution solvents (heptane, dichloromethane, and ethanol) were used for each type of adsorbent. Hansen solubility parameters can be used to …


Synthesis And Characterization Of Surface-Modified Magnetic Mesoporous Silicate Materials For Phosphate Adsorption, Ayşegül Gençer, Burcu Uysal Karataş, Önder Topel, Nadir Ki̇raz Feb 2024

Synthesis And Characterization Of Surface-Modified Magnetic Mesoporous Silicate Materials For Phosphate Adsorption, Ayşegül Gençer, Burcu Uysal Karataş, Önder Topel, Nadir Ki̇raz

Turkish Journal of Chemistry

The magnetic mesoporous silica material, Mag-MCM-41, was synthesized by coating magnetite (Fe3O4) nanoparticles with a mesoporous material called MCM-41. Mag-MCM-41 and modified nanomaterials Mag-MCM-41-NN and Mag-MCM-41-NN-Fe+3 which were modified with aminopropyl functional groups. In water and wastewater, phosphate anions are considered significant contaminants due to their detrimental impact on the environment. They promote the growth of algae, leading to eutrophication. The purpose of this study is to investigate the removal of phosphate anions from aqueous solutions using modified magnetic silica particles. The Mag-MCM-41 material exhibits hexagonal properties and belongs to the class of “mesoporous” materials. It has a surface area …


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 Feb 2024

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 …


Hydroxyl- Terminated Dendrimers With Sulfonimide Linkers As Binders For Metals Of Industrial Significance, Khaleel Abu Sbeih, Mohammad Al Harahsheh Feb 2024

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+.


Exploration Of Novel 6,8,9-Trisubstituted Purine Analogues: Synthesis, In Vitro Biological Evaluation, And Their Effect On Human Cancer Cells, Muhammed Fatih Polat, İrem Durmaz Şahi̇n, Rengül Atalay, Meral Tunçbi̇lek Feb 2024

Exploration Of Novel 6,8,9-Trisubstituted Purine Analogues: Synthesis, In Vitro Biological Evaluation, And Their Effect On Human Cancer Cells, Muhammed Fatih Polat, İrem Durmaz Şahi̇n, Rengül Atalay, Meral Tunçbi̇lek

Turkish Journal of Chemistry

Cancer, a leading global cause of mortality, demands continuous advancements in therapeutic strategies. This study focuses on the design and synthesis of a novel series of purine derivatives, specifically 6-(substituted phenyl piperazine)-8-(4-phenoxyphenyl)-9-cyclopentyl purine derivatives (5–11). The motivation behind this endeavor lies in addressing acquired resistance mechanisms in cancer cells, a significant hurdle in current treatment modalities. The synthesis, starting from 4,6-dichloro-5-nitropyrimidine, involves a multi-step process, resulting in seven new purine derivatives. Biological evaluation against human liver, colon, and breast cancer cells (Huh7, HCT116, and MCF7, respectively) was performed using the SRB assay. Among the synthesized analogs, compounds 5 and 6, …


Copolymerization Of Pyrrole And Carbazole Onto Polyester Textile, Mehmet Akif Küçükkaya, Utku Ustamehmetoğlu, Esma Sezer, Belkıs Ustamehmetoğlu Feb 2024

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 …


Influence Of Convective Heat Transfer Coefficients On Thermal Behaviour Of A Lithium-Ion Cell: A Numerical Study, Uğur Morali Feb 2024

Influence Of Convective Heat Transfer Coefficients On Thermal Behaviour Of A Lithium-Ion Cell: A Numerical Study, Uğur Morali

Turkish Journal of Chemistry

In the current study, the impact of C-ratio, convective heat transfer coefficient, and free stream temperature on the maximal cell temperature and temperature uniformity was computationally and statistically examined. Results revealed that the free stream temperature was the main influential factor for the maximal cell temperature for both natural and forced convection conditions while the C-ratio was the most effective parameter for the temperature uniformity for both natural and forced convections. On the other hand, the contribution of the free stream temperature to the maximum battery temperature increased from 63% to 94% when the conditions were changed from natural convection …


Palladium (0) Nanoparticles Distributed On Lanthanum (Iii) Oxide As An Effective Catalyst For The Methanolysis Of Hydrazine-Borane To Produce Hydrogen, Adem Rüzgar, Lokman Şener, Yaşar Karataş, Mehmet Gülcan Feb 2024

Palladium (0) Nanoparticles Distributed On Lanthanum (Iii) Oxide As An Effective Catalyst For The Methanolysis Of Hydrazine-Borane To Produce Hydrogen, Adem Rüzgar, Lokman Şener, Yaşar Karataş, Mehmet Gülcan

Turkish Journal of Chemistry

Pd (0) nanoparticles (NPs) distributed on lanthanum (III) oxide were ex situ generated from the reduction of Pd2+ ions using NaBH4 as reducing agent. The Pd/La2O3 displayed good catalytic activity in H2(g) releasing from the hydrazine-borane (HB) methanolysis reaction and it was identified by advanced techniques. Pd/La2O3 was found to be an active catalyst procuring three equiv. H2(g) per mole of HB. The results from TEM images represent the formation of Pd (0) NPs with an average particle size of 1.94 ± 0.1 nm on the surface of La2O3. Moreover, Pd/La2O3 with various Pd loadings were prepared and tested as …


Structure-Activity Relationship Of Anticancer Drug Candidate Quinones, Nadire Özenver, Neslihan Sönmez, Merve Yüzbaşıoğlu Baran, Ayşe Uz, Lütfiye Ömür Demi̇rezer Feb 2024

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. …


Nonoxidative Dehydrogenation Of Propane Using Boron-Incorporated Silica-Supported Pt Sites Synthesized By Atomic Layer Deposition, Gokhan Çeli̇k Feb 2024

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 Feb 2024

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 Feb 2024

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 Feb 2024

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 …


Traffic Signal Optimization Using Multiobjective Linear Programming For Oversaturated Traffic Conditions, Mustafa Murat Coşkun, Cevat Şener, İsmail Hakkı Toroslu Feb 2024

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 Feb 2024

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 …


Grey Wolf Optimization Algorithm-Based Robust Neural Learning Control Of Passive Torque Simulators With Predetermined Performance, Seyyed Amirhossein Saadat, Mohammad Mehdi Fateh, Javad Keighobadi Feb 2024

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 …


Fast Grid Search: A Grid Search-Inspired Algorithm For Optimizing Hyperparameters Of Support Vector Regression, Mustafa Açikkar Feb 2024

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 …


Differentially Private Online Bayesian Estimation With Adaptive Truncation, Sinan Yildirim Feb 2024

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 …


Milp Modeling Of Matrix Multiplication: Cryptanalysis Of Klein And Prince, Murat Burhan İlter, Ali Aydın Selçuk Feb 2024

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 …