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First Insights Into The Origin Of Iron In Eastern Cilicia During The Iron Age, Using Osmium Isotope And Trace Element Analysis, Ivan Stepanov, Hüseyi̇n Öztürk, Michael Brauns, Ernst Pernicka, Nurullah Hanilçi, Ümi̇t Güder Sep 2025

First Insights Into The Origin Of Iron In Eastern Cilicia During The Iron Age, Using Osmium Isotope And Trace Element Analysis, Ivan Stepanov, Hüseyi̇n Öztürk, Michael Brauns, Ernst Pernicka, Nurullah Hanilçi, Ümi̇t Güder

Turkish Journal of Earth Sciences

Due to the abundance of ore resources and the probable technological advances of the Hittite civilisation, the Anatolian plateau is conventionally regarded as “the birthplace” of iron smelting technology. The present paper presents a complex archaeometric investigation of iron production remains from the Middle and Late Iron Age phases (c. 750–575 BC) at Kinet Höyük, a major trading port on the coast of eastern Cilicia (modern-day Dörtyol, Hatay). To provide an initial insight into the sources of iron processed at Kinet Höyük and to generate an overview of the 187Os/188Os and 187Re/188Os isotope ratios expected from eastern Anatolian iron ores, …


Coseismic Surface Deformation Analyses Using Sar And Optical Images: 2023 Kahramanmaraş Earthquake Sequence, Türkiye, Han-Kyung Bae, Gwang-Woo Oh, Jin-Hyuck Choi Sep 2025

Coseismic Surface Deformation Analyses Using Sar And Optical Images: 2023 Kahramanmaraş Earthquake Sequence, Türkiye, Han-Kyung Bae, Gwang-Woo Oh, Jin-Hyuck Choi

Turkish Journal of Earth Sciences

The 2023 Kahramanmaraş earthquake sequence in Türkiye, including Mw 7.7 and 7.6 mainshocks, caused significant surface ruptures along the East Anatolian Fault (EAF) and Sürgü–Çardak Fault (SCF). We calculated the coseismic displacement fields through pixel offset tracking (POT) analysis of Sentinel-1 SAR data and optical image correlation (OIC) analysis of Sentinel-2 imagery. Our results reveal distinct sinistral motion along both the EAF and SCF, with maximum offsets of about 7 and 9 m, respectively. Deformation zones were identified both on and off the fault, highlighting the relationship between the rupture geometry and the broader deformation field. A comparative evaluation of …


Geomagnetic Activity For The Kp = 7.3 Geomagnetic Storm In November 2023 Assessed By Observational Data, Eli̇f Çi̇ftçi̇, Özlem Hacioğlu Sep 2025

Geomagnetic Activity For The Kp = 7.3 Geomagnetic Storm In November 2023 Assessed By Observational Data, Eli̇f Çi̇ftçi̇, Özlem Hacioğlu

Turkish Journal of Earth Sciences

The geomagnetic storm of 4–6 November 2023, driven by an Earth-directed coronal mass ejection (CME), was a significant event marked by a peak geomagnetic activity index (Kp) of 7.3 on a 0–9 scale, indicating severe disturbance in Earth’s magnetic field. This CME-induced storm was characterized by intense auroral displays and reached a G3 level (Dst = −172 nT) around 12:40 UT on 5 November, with auroras observed at midlatitudes across Europe. This study examines the effects of the storm on the horizontal (H), declination (D), and vertical (Z) components of the geomagnetic field using data from sunlit-side magnetometer measurements. Planetary …


Preliminary Petrological, Mineralogical, And Geochemical Evaluation Of A Newly Discovered Lignite Field In Yatağan, Muğla (Sw Türkiye), Işik Hacimustafaoğlu, Mehmet Akbulut, Hülya İnaner, Kimon Christanis Sep 2025

Preliminary Petrological, Mineralogical, And Geochemical Evaluation Of A Newly Discovered Lignite Field In Yatağan, Muğla (Sw Türkiye), Işik Hacimustafaoğlu, Mehmet Akbulut, Hülya İnaner, Kimon Christanis

Turkish Journal of Earth Sciences

Thirty-two coal and seven inorganic core samples from a newly discovered coalfield in the Yatağan region of the Muğla Basin were analysed to reconstruct the depositional palaeoenvironment. The coal has an average bed moisture of 34.60%, an ash yield of 33.73% (db), a volatile matter yield of 57.91% (daf), and a gross calorific value of 12.18 MJ/kg (maf). It is composed of mainly huminite macerals (up to 91 vol.%, on whole-rock basis), predominantly densinite, along small amounts of liptinite and inertinite macerals. The average random reflectance of huminite is 0.28%, and the primary minerals identified include pyrite, quartz, and clay …


Quick Antiquing Of Natural Stones In The Restoration Process, Hakan Elçi̇ Sep 2025

Quick Antiquing Of Natural Stones In The Restoration Process, Hakan Elçi̇

Turkish Journal of Earth Sciences

When ancient buildings are restored, even though the restored section uses natural stone with the same lithological characteristics and texture as the building, there is a noticeable color difference between the restored and ancient portions of the building, signifying an old/new difference. This color difference, which is caused by the deterioration of the natural stone used in the ancient structure over many years, gives the natural stone a black or brown appearance. In this study, white marble, travertine, and sandstone were treated with antiquing techniques described in the literature. The goal was to identify the technique that produces the most …


Trcaptionnet++: A High-Performance Encoder-Decoder Based Deep Turkish Image Captioning Model Fine-Tuned With A Large-Scale Set Of Pretrain Data, Serdar Yildiz, Abbas Memi̇ş, Songül Varli Sep 2025

Trcaptionnet++: A High-Performance Encoder-Decoder Based Deep Turkish Image Captioning Model Fine-Tuned With A Large-Scale Set Of Pretrain Data, Serdar Yildiz, Abbas Memi̇ş, Songül Varli

Turkish Journal of Electrical Engineering and Computer Sciences

This paper introduces a novel and high-performance encoder-decoder-based deep model called TRCaption Net++ for generic Turkish image captioning tasks. The proposed model is an improved and refined version of TRCap tionNet, which essentially employs a CLIP (contrastive language–image pretraining) image encoder, a feature projection layer and a BERT (bidirectional encoder representations from transformers) text decoder. Within the scope of the study, the regular TRCaptionNet model was trained and specifically fine-tuned with a massive set of image data. In this respect, approximately 2,000,000 random images representing the words in the MS COCO and Flickr caption sets were retrieved through web crawling …


Enhanced Pmu Data Imputation Using Variational Autoencoder: A Novel Approach For Improved Accuracy, Subin Koshy, Sunitha Rajan, Elizabeth P. Cheriyan Sep 2025

Enhanced Pmu Data Imputation Using Variational Autoencoder: A Novel Approach For Improved Accuracy, Subin Koshy, Sunitha Rajan, Elizabeth P. Cheriyan

Turkish Journal of Electrical Engineering and Computer Sciences

Data collected from various measurement devices, such as phasor measurement units (PMUs), form the backbone of power system monitoring algorithms such as state estimation algorithms. Even though modern PMUs are efficient, data inaccuracies and loss can still occur due to problems like equipment malfunctions, communication issues, and hardware or software glitches. Missing values in the datasets can also affect the overall quality, impacting the algorithms dependent on them. This article introduces a novel technique for real-time imputation of missing data using variational autoencoder (VAE) and utilizing the latent space representation acquired from VAE. The method has demonstrated enhanced accuracy in …


Automatic Detection Of Depression Using A Cnn-Transformer Model Based On Low-Channel Eeg Data, Dongfang Yu, Penghai Li, Fei Su, Kun Wang, Shutong Duan, Ding Yuan Sep 2025

Automatic Detection Of Depression Using A Cnn-Transformer Model Based On Low-Channel Eeg Data, Dongfang Yu, Penghai Li, Fei Su, Kun Wang, Shutong Duan, Ding Yuan

Turkish Journal of Electrical Engineering and Computer Sciences

Background: Accurate and portable diagnostic tools for Major Depressive Disorder (MDD) remain a critical unmet need in clinical practice. Electroencephalography (EEG), with its noninvasiveness and high sensitivity, presents an ideal modality, yet traditional multi-channel EEG systems limit clinical convenience and practical deployment. Methods: We developed a novel CNN-Transformer hybrid model using only eight EEG channels selected from frontal regions to detect MDD. Minimal preprocessing steps (basic filtering) were applied to EEG data before the model automatically learned both local and global signal features through convolutional and self-attention mechanisms. We validated this method through comprehensive experiments, including within-dataset and cross-dataset evaluations, …


Electronically Tunable Cccii And Ota-Based Fractional-Order Meminductor Emulator And Its Application, Bhawna Aggarwal, Rupam Das, Shireesh Kumar Rai Sep 2025

Electronically Tunable Cccii And Ota-Based Fractional-Order Meminductor Emulator And Its Application, Bhawna Aggarwal, Rupam Das, Shireesh Kumar Rai

Turkish Journal of Electrical Engineering and Computer Sciences

In this paper, two fractional-order meminductor (FOMI) emulators have been realized using second-generation current-controlled conveyor (CCCII) and operational transconductance amplifier (OTA). In the first realization, two OTAs, one CCCII, one resistor, one fractional-order capacitor, and one integer-order capacitor are used. In the second configuration two CCCIIs, one OTA, two resistors, one fractional-order capacitor, and one integer-order capacitor are used. Pinched hysteresis loops have been achieved for a wide range of frequencies. The robustness of the proposed FOMI emulators has been verified through formation of pinched hysteresis loops under process, voltage, and temperature variations. Other characteristics, such as transient analysis, nonvolatility …


Cover And Contents Sep 2025

Cover And Contents

Turkish Journal of Electrical Engineering and Computer Sciences

No abstract provided.


A Comprehensive Approach For Design And Optimization Of A High Power Density Interior Permanent Magnet Motor For Evs, Bati Eren Ergun, Ahmet Hakan Oğuz, Güven Onur, Zeynep Akyüz, Derya Kocabaş, Mehmet Onur Gülbahçe Sep 2025

A Comprehensive Approach For Design And Optimization Of A High Power Density Interior Permanent Magnet Motor For Evs, Bati Eren Ergun, Ahmet Hakan Oğuz, Güven Onur, Zeynep Akyüz, Derya Kocabaş, Mehmet Onur Gülbahçe

Turkish Journal of Electrical Engineering and Computer Sciences

This study presents a comprehensive design and optimization framework that addresses both electromagnetic and thermal aspects of an interior permanent magnet synchronous motor (IPMSM) intended for use in midsize commercial EVs. A 60-slot/10-pole IPMSM with a V-shaped rotor, capable of delivering 125 kW peak power at 4500 rpm from a 400 VDC bus, has been developed using a systematic approach. The design process begins with analytical estimations to determine initial motor geometry and performance parameters, followed by a finite element-based validation. To enhance performance, a multiobjective optimization is conducted using the nondominated sorting genetic algorithm II (NSGA-II). The optimization targets …


Yoganglenet: Body Angle-Based Yogic Posture Classification Approach Using Mediapipe From Single-Person Images, Arun Kumar Rajendran, Sibi Chakkaravarthy Sethuraman Sep 2025

Yoganglenet: Body Angle-Based Yogic Posture Classification Approach Using Mediapipe From Single-Person Images, Arun Kumar Rajendran, Sibi Chakkaravarthy Sethuraman

Turkish Journal of Electrical Engineering and Computer Sciences

The profound psychological and physical benefits of yoga have attracted global interest. This study explores yoga pose classification using angle values derived from single-person posture images. The dataset is carefully curated and consists exclusively of single-person yoga postures. The proposed method applies feature selection to improve model performance, achieving high accuracy with the random forest (RF) classifier. Using the top four selected features, our approach attains a maximum testing accuracy of 92.63%. A key contribution of this study is its strong focus on model interpretability. To explain model predictions and clarify decision-making, we employ Local Interpretable Model-Agnostic Explanations (LIME) and …


Fractional-Order Adaptive Terminal Sliding Mode Control For Synchronization Of Uncertain Chaotic Memristive Chua's Circuit, Dorukhan Asteki̇n, Fati̇h Adigüzel Sep 2025

Fractional-Order Adaptive Terminal Sliding Mode Control For Synchronization Of Uncertain Chaotic Memristive Chua's Circuit, Dorukhan Asteki̇n, Fati̇h Adigüzel

Turkish Journal of Electrical Engineering and Computer Sciences

Memristive-based chaotic dynamical systems exhibit chaotic behavior with signals of unpredictable complex ity, making it difficult to achieve full synchronization in master-slave systems. Therefore, an advanced synchronization method is required to overcome the chaotic model uncertainties and external disturbances. In this study, a fractional order terminal sliding mode synchronization is proposed for the uncertain memristive chaotic Chua’s circuit. After presenting the integer-order model of the chaotic memristive Chua’s circuit, a fractional-order sliding surface-based non linear synchronization structure, incorporating the fractional derivative operator, is designed. The convergence of the synchronization closed-loop system is proven using Lyapunov theory. To demonstrate its effectiveness …


Electromagnetic Simulations Of Antennas On Gpus For Machine Learning Applications, Murat Temi̇z, Vemund Bakken Sep 2025

Electromagnetic Simulations Of Antennas On Gpus For Machine Learning Applications, Murat Temi̇z, Vemund Bakken

Turkish Journal of Electrical Engineering and Computer Sciences

This study proposes an antenna simulation framework powered by graphics processing units (GPUs) based on an open-source electromagnetic (EM) simulation software (gprMax) for machine learning applications of antenna design and optimization. Furthermore, it compares the simulation results with those obtained through commercial EM software. The proposed software framework for machine learning and surrogate model applications will produce antenna data sets consisting of a large number of antenna simulation results using GPUs. Although machine learning methods can attain the optimum solutions for many problems, they are known to be data-hungry and require a great deal of samples for the training stage …


Basgit: A Secure Digital Epassport Alternative, Ceren Kocaoğullar, Kaan Yildirim, Mert Ati̇la Sakaoğullari, Alpteki̇n Küpçü Sep 2025

Basgit: A Secure Digital Epassport Alternative, Ceren Kocaoğullar, Kaan Yildirim, Mert Ati̇la Sakaoğullari, Alpteki̇n Küpçü

Turkish Journal of Electrical Engineering and Computer Sciences

We present a solution to the challenge of securely issuing both paper-based and mobile phone-based passports without requiring specialized production techniques. Our solution offers improved security, privacy, and usability compared to the ePassport mechanism currently used worldwide. We also describe how our solution can be extended to support offline verification and present the test results of our proof-of-concept implementation.


Nontarget Effects Of Abamectin On Cysts And Three Larval Stages Of Marine Microcrustacean Artemia Franciscana, Hashem Khandan Barani, Sahel Pakzad Toochaei, Narjes Sanchooli Sep 2025

Nontarget Effects Of Abamectin On Cysts And Three Larval Stages Of Marine Microcrustacean Artemia Franciscana, Hashem Khandan Barani, Sahel Pakzad Toochaei, Narjes Sanchooli

Turkish Journal of Zoology

Abamectin (ABM) is a widely used pesticide in agriculture and aquaculture worldwide. However, limited information is available on the toxic impacts of ABM on nontarget marine organisms, necessitating further research to investigate the toxic impacts of ABM on marine life. Hence, this study examined the acute (0.5–2.5 μg/L for 24 and 48 h) and chronic (0.125–0.5 μg/L for 7 days) toxicity of ABM on the marine microcrustacean Artemia franciscana under different incubation conditions and at different stages of development. To simulate a more realistic environmental scenario, some of the exposure tests were conducted in the presence of food or with …


Environmental Controls On Planktonic Community Variability And Ecosystem Responses In The Romanian Black Sea, Cristina Tabarcea, Elena Bișinicu, George-Emanuel Harcotă, Aurelia Țoțoiu, Oana Vlas, Elena Pantea, Luminita Lazar Sep 2025

Environmental Controls On Planktonic Community Variability And Ecosystem Responses In The Romanian Black Sea, Cristina Tabarcea, Elena Bișinicu, George-Emanuel Harcotă, Aurelia Țoțoiu, Oana Vlas, Elena Pantea, Luminita Lazar

Turkish Journal of Zoology

This study examines the structure, distribution, and environmental influences on planktonic communities in the Romanian Black Sea, based on data collected from Black Sea national monitoring stations in June 2023. We assessed the qualitative and quantitative composition of phytoplankton, microzooplankton, mesozooplankton, macrozooplankton, and ichthyoplankton, alongside key environmental factors such as temperature, salinity, dissolved oxygen, and nutrient concentrations (nitrite, nitrate, ammonium, phosphate, and silicate). The results highlight the dominance of dinoflagellates within the phytoplankton community, while copepods constitute the most abundant mesozooplankton group. Species from the Codonellidae family mainly represent microzooplankton diversity, while macrozooplankton is largely dominated by the scyphozoan Aurelia …


Cytotoxic And Genotoxic Effects Of Minor Temperature Changes And Zinc Oxide Nanoparticles Synthesized Using Plantago Major On Oncorhynchus Mykiss Gonadal Cells, Semra Çi̇çek, Sevda Işik Sep 2025

Cytotoxic And Genotoxic Effects Of Minor Temperature Changes And Zinc Oxide Nanoparticles Synthesized Using Plantago Major On Oncorhynchus Mykiss Gonadal Cells, Semra Çi̇çek, Sevda Işik

Turkish Journal of Zoology

Temperature changes and nanoparticle exposure have emerged as critical environmental stressors with potential cytotoxic and genotoxic effects on aquatic species. This study investigates the impact of zinc oxide nanoparticles (ZnO NPs), synthesized using Plantago major leaves, on Oncorhynchus mykiss gonadal (RTG-2) cells under different temperature conditions (23 °C, 24 °C, and 25 °C). RTG-2 cells were exposed to hexagonal ZnO NPs (≤100 nm) at concentrations of 6.25, 12.5, 25, 50, 75, and 100 μg/mL for 24 and 48 h. Cytotoxicity was assessed using the sulforhodamine B assay, and genotoxicity was evaluated via the comet assay. Results demonstrated that both temperature …


Symbiotic Aspergillus Terreus Alleviates Drought And Waterlogged Stress In Zea Mays L., Hazrat Ali, Fayaz Asad, Naveen Dilawar, Vasila Sharipova, Imtiaz Ahmad, Abida Zeb Sep 2025

Symbiotic Aspergillus Terreus Alleviates Drought And Waterlogged Stress In Zea Mays L., Hazrat Ali, Fayaz Asad, Naveen Dilawar, Vasila Sharipova, Imtiaz Ahmad, Abida Zeb

Turkish Journal of Botany

The interaction concerning rhizospheric fungi and plants is essential for enhancing plant resilience in the face of abiotic stress conditions. This study investigated the effects of the rhizospheric fungus Aspergillus terreus on maize (Zea mays L.) growth under both drought and waterlogging conditions. Our findings confirmed that inoculation with A. terreus mitigated the adverse effects of drought and waterlogging conditions on maize growth. Plants treated with Aspergillus terreus (A. terreus) exhibited enhanced root and shoot length, fresh and dry weight as well as enhanced chlorophyll content in plants compared to control, under stress-related conditions. Compared to the control group, A. …


Advanced Deep Learning Approaches For The Accurate Classification Of Phallaceae Fungi With Explainable Ai, Eda Kumru, Fati̇h Eki̇nci̇, Koray Açici, Ömer Burak Altindal, Mehmet Serdar Güzel, Ilgaz Akata Sep 2025

Advanced Deep Learning Approaches For The Accurate Classification Of Phallaceae Fungi With Explainable Ai, Eda Kumru, Fati̇h Eki̇nci̇, Koray Açici, Ömer Burak Altindal, Mehmet Serdar Güzel, Ilgaz Akata

Turkish Journal of Botany

In this study, deep learning (DL)-based models were developed for the classification of 5 fungal species from the Phallaceae family (Clathrus ruber, Colus hirudinosus, Mutinus caninus, Phallus impudicus, and Pseudocolus fusiformis). ConvNeXT achieved the highest performance with 98% accuracy, 98% precision, 98% recall, and 98% F1-score. EfficientNetB4 and Xception also performed well with 96% accuracy. In contrast, lighter models such as MobileNetV2 and MixNet S showed significantly lower accuracy (84% and 80%, respectively). Among the explainable artificial intelligence (XAI) techniques, gradient-weighted class activation mapping (Grad-CAM) and Integrated Gradients showed that high-accuracy models focus more effectively on biologically meaningful regions. In …


Erratum To “Anatomical And Palynological Studies On Turkish Primula Taxa (Primulaceae) And Their Taxonomic And Phylogenetic Significance [Turkish Journal Of Botany 49 (4) 2025 325-348 ] ”, Deni̇z Ulukuş, Esengül Özkaymakoğlu, Rebecca Stubbs, Hüseyi̇n Baykal, Kami̇l Coşkunçelebi̇, Osman Tugay, Barbara Keller, Elena Conti, Ferhat Celep Sep 2025

Erratum To “Anatomical And Palynological Studies On Turkish Primula Taxa (Primulaceae) And Their Taxonomic And Phylogenetic Significance [Turkish Journal Of Botany 49 (4) 2025 325-348 ] ”, Deni̇z Ulukuş, Esengül Özkaymakoğlu, Rebecca Stubbs, Hüseyi̇n Baykal, Kami̇l Coşkunçelebi̇, Osman Tugay, Barbara Keller, Elena Conti, Ferhat Celep

Turkish Journal of Botany

This erratum addresses an error concerning Figure 5 in the original published version of this article. During the typesetting process, Figure 5 was partially omitted, resulting in an incomplete figure being published.To correct this oversight and ensure the accuracy of the scholarly record, the complete Figure 5 is provided below for reference.

Link to the original article: https://doi.org/10.55730/1300-008X.2866


Next-Generation Biotechnology And Breeding Strategies For The Development Of Biotic Stress-Resistant Sugar Beet, Songül Gürel, Mehmet Cengi̇z Baloğlu, Pinar Baloğlu, Mehmet Kolçak, Ferhat Ulu, Ömer Can Ünüvar, Mehmet Örgeç, Özge Kaya, Ramazan Polat, Cemi̇le Köseoğlu, Yasemi̇n Çeli̇k Altunoğlu, Hati̇ce Korkmaz Güvenmez, Ekrem Gürel Sep 2025

Next-Generation Biotechnology And Breeding Strategies For The Development Of Biotic Stress-Resistant Sugar Beet, Songül Gürel, Mehmet Cengi̇z Baloğlu, Pinar Baloğlu, Mehmet Kolçak, Ferhat Ulu, Ömer Can Ünüvar, Mehmet Örgeç, Özge Kaya, Ramazan Polat, Cemi̇le Köseoğlu, Yasemi̇n Çeli̇k Altunoğlu, Hati̇ce Korkmaz Güvenmez, Ekrem Gürel

Turkish Journal of Botany

Sugar beet is a high-sucrose crop primarily used for sugar production, and it is now gaining attention as a promising source for bioethanol production and cattle feed. This crop is also utilized for the extraction of pectin and the production of molasses. Despite its utilization across a wide range of industries, abiotic and biotic stress factors greatly reduce the productivity of the cash crop sugar beet. In this paper, we focus on the development of biotic stress-resistant sugar beet plants through various classical and biotechnological applications. In recent decades, omics technologies, next-generation sequencing, gene editing/silencing, and overexpression techniques have been …


Cover And Contents Sep 2025

Cover And Contents

Turkish Journal of Mathematics

No abstract provided.


Improved Berezin Radius Inequalities For Functional Hilbert Space Operators, Mojtaba Bakherad, Ulaş Yamanci, Mohammad W. Alomari Sep 2025

Improved Berezin Radius Inequalities For Functional Hilbert Space Operators, Mojtaba Bakherad, Ulaş Yamanci, Mohammad W. Alomari

Turkish Journal of Mathematics

The Berezin number of an operator S is defined by ber(S) = supλ∈Θ |Ŝ(λ)| = supλ∈Θ |⟨Sĸ̂λ, ĸ̂λ⟩|, where Ŝ(λ) = ⟨Sĸ̂λ, ĸ̂λ⟩ (λ ∈ Θ) is the Berezin transform of an operator S on the functional Hilbert space ℋ = ℋ(Θ) and ĸ̂λ = ĸλ / ‖ĸλ‖ is the normalized reproducing kernel of ℋ. In this paper, we show an improvement of the classical Cauchy–Schwarz inequality involving the Berezin number. Moreover, some Berezin numbers inequalities are proven for invertible operators.


Nonoscillatory Solutions Of Third-Order Nonlinear Dynamic Equations: Existence And Nonexistence, Özkan Öztürk, Elvan Akin, Nesli̇han Nesli̇ye Pelen Sep 2025

Nonoscillatory Solutions Of Third-Order Nonlinear Dynamic Equations: Existence And Nonexistence, Özkan Öztürk, Elvan Akin, Nesli̇han Nesli̇ye Pelen

Turkish Journal of Mathematics

This paper investigates a third-order nonlinear dynamic equation on arbitrary time scales, a nonempty closed subset of the real numbers, unifying continuous and discrete analyses. We study the qualitative behavior of nonoscillatory solutions and their quasi-derivatives, focusing on their limiting behaviors. The existence of such solutions are established using improper integral criteria and Schauder’s and Knaster’s fixed point theorems. In addition, we establish the criteria for the nonexistence of nonoscillatory solutions. Furthermore, we prove the existence of Kneser-type solutions of the corresponding linear dynamic equation on isolated time scales, addressing an open problem in the literature. Several examples of theoretical …


Structural Stability For Damped Nonlinear Wave Equations, Sevda Isayeva, Varga Kalantarov Sep 2025

Structural Stability For Damped Nonlinear Wave Equations, Sevda Isayeva, Varga Kalantarov

Turkish Journal of Mathematics

We study the problem of continuous dependence on parameters for solutions to initial-boundary value problems for nonlinear strongly damped wave equations. Specifically, we consider three classes of equations: a strongly damped wave equation with a nonlinear damping term; a strongly damped wave equation incorporating both a nonlinear damping term and a nonlinear source term; and a strongly damped wave equation with a nonlinear source term and a linear weak damping term. For each class, we establish structural stability results, showing that the solutions depend continuously on the relevant parameters.


The Generalization Of Rectifying Helices, Bülent Altunkaya Sep 2025

The Generalization Of Rectifying Helices, Bülent Altunkaya

Turkish Journal of Mathematics

This work establishes connections between different classes of arbitrary speed rectifying helices. We further analyze how the involute of a space curve can exhibit spherical helicity and how the evolute can inherit rectifying properties, thereby providing an alternative characterization of these helices. These relationships, along with their interplay with involutes and evolutes, are supported by illustrative examples that offer deeper insights into their geometric properties.


Applications Of A New Linear Operator Involving Dziok-Srivastava Operator And Bessel Function Of The First Kind, Daniela Andrada Bardac-Vlada, Georgia Irina Oros Sep 2025

Applications Of A New Linear Operator Involving Dziok-Srivastava Operator And Bessel Function Of The First Kind, Daniela Andrada Bardac-Vlada, Georgia Irina Oros

Turkish Journal of Mathematics

This study introduces a new linear operator constructed from the well-known Dziok–Srivastava linear hypergeometric operator, the Bessel function of the first kind, and convolution. Applying the new operator, a class of functions with positive real part is defined and investigated concerning inclusion relations, the necessary and sufficient conditions for functions to belong to this class, as well as starlikeness and convexity conditions. The properties of the new class to be convex of a certain order, close-to-convex and starlike of a certain order are highlighted and examples are also included to prove that the new outcome is applicable. The methods employed …


Innovative Approaches To Estimating Sessile Oak Stem Volume: Comparing Additive Models And Ensemble Machine Learning, Maria J. Diamantopoulou, Abbas Şahi̇n, Ramazan Özçeli̇k Aug 2025

Innovative Approaches To Estimating Sessile Oak Stem Volume: Comparing Additive Models And Ensemble Machine Learning, Maria J. Diamantopoulou, Abbas Şahi̇n, Ramazan Özçeli̇k

Turkish Journal of Agriculture and Forestry

Sessile oak is an important deciduous forest tree species across Türkiye and Europe. Estimating individual tree and stand volumes is essential for growth and yield models, as these predictions play a critical role in assessing forest management, economics, and fire risk. In pursuit of this goal, nonlinear seemingly unrelated regression (NSUR) was used for the simultaneous fitting of stem volume components, and compared to three ensemble machine learning techniques: gradient boosting regression (GBr), XGBoost regression (XGBr), and random forest regression (RFr). NSUR accounts for correlations between error terms across different equations, leading to more efficient parameter estimates than if each …


Effects Of Storage Temperatures On Quality And Phytochemical Properties Of The Hawthorn (Crataegus Azarolus L.) During Storage And Shelf Life, Ahmet Erhan Özdemi̇r, Oğuzhan Çalişkan, Safder Bayazit, Kazi̇m Gündüz, Nurdan Tuna Güneş, Zafer Karaşahi̇n, Derya Kiliç, Ramazan Bestami̇ Karahan Aug 2025

Effects Of Storage Temperatures On Quality And Phytochemical Properties Of The Hawthorn (Crataegus Azarolus L.) During Storage And Shelf Life, Ahmet Erhan Özdemi̇r, Oğuzhan Çalişkan, Safder Bayazit, Kazi̇m Gündüz, Nurdan Tuna Güneş, Zafer Karaşahi̇n, Derya Kiliç, Ramazan Bestami̇ Karahan

Turkish Journal of Agriculture and Forestry

This study aimed to investigate the effects of storage temperature on the quality and phytochemical characteristics in Sultan hawthorn cultivar during cold storage and shelf life. Fruits were stored at 0 ± 0.5 °C and 4 ± 0.5 °C and 90 ± 5% relative humidity (RH) for 6 months in cold storage and were analyzed every month. In addition, hawthorn fruits were kept at 20 ± 0.5 °C and 75 ± 5% RH for 7 days, and their shelf life was investigated at monthly intervals. Weight loss, appearance, the incidence of physiological disorders and fungal decay, fruit skin color, firmness, …