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Optimization of Signalized Intersections: Analyzing Autonomous Vehicle Behaviors Through Data-Driven Simulations
(Springer Science and Business Media Deutschland GmbH, 2026) Qadri, Syed Shah Sultan Mohiuddin; Albdairi, Mustafa; Almusawi, Ali; Kabarcik, Ahmet; Abdulrahman, H. S.
Autonomous vehicles (AVs) present a transformative opportunity to enhance traffic flow, particularly at urban intersections where delays are most frequent. This study investigates how different AV driving behaviors and penetration rates affect traffic efficiency at signalized intersections. Using a microscopic simulation model in PTV VISSIM, the research centers on a four-way intersection in Balgat, Ankara. Five AV driving behaviors—cautious, normal, aggressive, platooning, and mixed—are modeled under various signal cycle lengths. The simulation’s accuracy was ensured through calibration and validation with real-world traffic data. The findings reveal that the integration of AVs can significantly improve traffic flow, with aggressive and platooning driving behaviors achieving the most notable reduction in vehicle delays, particularly at shorter cycle lengths (60–70 s). Increased AV penetration rates amplify these positive effects, reducing delays and queue lengths in all tested scenarios. In contrast, cautious AV behaviors led to more significant delays, highlighting the importance of intelligent AV driving strategies for optimizing traffic management. The results underscore that optimizing signal cycle lengths with AV integration can reduce congestion and improve urban traffic flow. While the study demonstrates the potential of AVs to enhance urban traffic management, it also stresses the need for real-world validation and the development of adaptive traffic signal systems capable of accommodating diverse driving behaviors. These insights offer urban planners and policymakers valuable guidance on integrating AVs into current infrastructure to create more resilient and efficient transportation networks. © 2025 Elsevier B.V., All rights reserved.
Artificial Intelligence in Dentistry
(CRC Press, 2025) Cagiltay, Nergiz Ercil; Kılıçarslan, Mehmet Ali; Basmaci, Fulya
Today, with advanced technologies, collecting detailed and big data from the environment and analyzing it using intelligent techniques has become possible, providing important insights into phenomena as well as future predictions. Big data is characterized by its high volume, velocity, and variety. Here, the volume is the amount and size of the data, which is measured in terabytes, petabytes, exabytes, or zettabytes. Velocity is the offered form of big data, which can be batch, near-real-time, real-time, or streaming. Finally, variety is the structure of the big data, which can be structured, such as in relational or dimensional models, as in warehouses, or unstructured, which is stored without any organization. It can also be in semi-structured form, where the data is unstructured but there is some meta-data or some tags for describing the data. Today, these forms of data are being collected for different dental purposes in several formats, such as images, raw data, or coordinates. © 2025 Elsevier B.V., All rights reserved.
Phenomenological Study of Lithium-Sodium Tetragermanate Close to the Phase Transition
(Springer Nature, 2025) Kiraci, Ali
This study presents an analysis of the dielectric and thermal properties in the vicinity of the second-order ferroelectric phase transition, with a specific emphasis on lithium-sodium tetragermanate, LiNaGe4O9. The power-law equation is employed by modifying the Kouvel-Fisher (KF) technique, which articulates the magnetization () and magnetic susceptibility in relation to the spontaneous polarization () and the dielectric constant () within ferroelectric frameworks. A parallel methodology is adopted to elucidate the heat capacity () and thermal expansivity () in the vicinity of phase transitions occurring in LiNaGe4O9. We demonstrate that the continuous fluctuations in and with temperature nearing the Curie point (TC108 K) as an indication of a second-order transition in LiNaGe4O9. Furthermore, a linear correlation is also established between and with temperature approaching the Curie point TC for this crystal structure. Experimental data are used from the literature for our analysis. Our findings show that the critical behavior of one dielectric or thermal property near the transition temperature in LiNaGe4O9 can be predicted from the other through these linear relationships. The methodology articulated herein for delineating the dielectric and thermal characteristics of LiNaGe4O9 close to the Curie point is extendable to various other ferroelectric materials. © 2025 Elsevier B.V., All rights reserved.
Introduction
(Springer Nature, 2022) Karapınar, Erdal; Agarwal, Ravi P.
Fixed point theory can be described as a framework for researching and investigating the existence of the solution of the equation f(p) = p for a certain self-mapping f that is defined on a non-empty set X. As is expected, here, p is called the fixed point of the mapping f. On the other side, we may re-consider the fixed point equation f(p) = p as T(p) = f(p) - p= 0 and, accordingly, finding the zeros of the mapping T and finding the fixed point of f becomes an equivalent statement. This equivalence, not only enriches the fixed point theory but also, opens the doors to a wide range of potential applications in the setting of almost all quantitative sciences. For example, let us consider one of the classical open problems of number theory, finding perfect numbers: Let p be a self-mapping on a natural number such that p(n) is the sum of all divisors of n for n> 1. Thus, any fixed points of the function p give a perfect number. In particular, 6 is the smallest perfect numbers, and 2 74207280× (2 74207281- 1 ), with 44, 677, 235 digits, is the biggest known perfect number. © 2022 Elsevier B.V., All rights reserved.
Introduction to the Special Issue on Mathematical Aspects of Computational Biology and Bioinformatics-I
(Tech Science Press, 2023) Baleanu, Dumitru; Pinto, Carla M. A.; Kumar, Sunil
Finite Orthogonal M Matrix Polynomials
(MDPI, 2025) Lekesiz, Esra Guldogan
In this study, we aim to construct a finite set of orthogonal matrix polynomials for the first time, along with their finite orthogonality, matrix differential equation, Rodrigues' formula, several recurrence relations including three-term relation, forward and backward shift operators, generating functions, integral representation and their relation with Jacobi matrix polynomials. Thus, the concept of "finite", which is used to impose parametric constraints for orthogonal polynomials, is transferred to the theory of matrix polynomials for the first time in the literature. Moreover, this family reduces to the finite orthogonal M polynomials in the scalar case when the degree is 1, thereby providing a matrix generalization of finite orthogonal M polynomials in one variable.
A Coupled Modelling and Simulation Approach to Electromagnetic Sheet Metal Forming
(Taylor & Francis Ltd, 2025) Aslan, Ozgur; Kabakci, Gamze Cakir; Sait, Ferit; Camalan, Caner; Baranoglu, Besim; Bayraktar, Emin
This study presents a coupled numerical and experimental investigation of electromagnetic forming (EMF) for aluminium sheets. A custom simulation framework is developed in ABAQUS/Standard using user-defined material (UMAT) and load (DLOAD) subroutines. The magnetic pressure exerted on the workpiece is computed through a finite difference-based solution of Maxwell's equations and applied to the mechanical solver. The mechanical response of the material is modelled using a strain-rate-sensitive plasticity law calibrated for aluminium 7075-O. Experimental forming trials are performed using a custom-built EMF setup, and the results are compared with numerical predictions to validate the model. The comparison shows strong agreement in deformation profiles, confirming the predictive capability of the proposed simulation strategy. This work offers a reliable computational tool for optimising EMF processes and provides insights into material behaviour under high strain rate electromagnetic loading.
Developing and Validating a Rubric-Based Approach to Quality Assurance in Turkish Higher Education
(Pergamon-Elsevier Science Ltd, 2025) Akkoyunlu, Buket; Bardakci, Salih; Yildirim, Sibel Aksu; Avsaroglu, M. Dilek; Uludag, Gonca; Kocer, Ayhan; Elmas, Muzaffer
This study, initiated by the Turkish Higher Education Quality Council (THEQC), develops and validates a rubricbased approach for evaluating institutional quality assurance (QA) processes within the Turkish higher education ecosystem. Effective quality assurance (QA) in higher education requires evaluation tools that are methodologically robust, responsive to institutional needs, and aligned with international benchmarks. A rubric-based approach offers a structured and transparent framework for consistent assessments. The rubric was created through an iterative, evidence-based process incorporating expert feedback, international benchmarks, site visits, and prior research. It consists of 22 main criteria across four key domains-Leadership, Governance and Quality; Learning and Teaching; Research and Development; and Service to Society-subdivided into 46 sub-criteria, each assessed on a five-point maturity scale. The validity and reliability of the rubric were rigorously examined. Content validity was established through evaluations by 10 QA professionals, addressing four key dimensions: relevance, alignment with the intended domain, appropriateness for the target audience, and clarity of language. Construct and criterion validity were assessed through consistency checks and usability analyses, with data collected from 252 external evaluators across 57 higher education institutions. Additionally, 360-degree feedback was gathered from both external evaluation teams and the institutions involved in the evaluation process. Results: demonstrate strong content validity (Lawshe coefficient =1.00, p < .05), high interrater consistency, and strong usability across various evaluator groups. Further evaluation confirmed the rubric's applicability and robustness across diverse institutional contexts. This study concludes that the developed rubric is a reliable and valid tool for enhancing and evaluating quality assurance practices in higher education.
Effects of Receiver Diversity on Bit Error Rate of Underwater Optical Wireless Communication Systems in Weak Oceanic Turbulence
(Springer, 2025) Gokce, Muhsin Caner; Baykal, Yahya; Ata, Yalcin
The receiver spatial diversity techniques are employed in underwater optical wireless communication (OWC) systems to mitigate oceanic turbulence, improving the bit error rate performance. In this paper, we consider an OWC system employing a binary phase-shift keying (BPSK) modulated Gaussian beam at the transmitter and employing receiver spatial diversity at the receiver. The techniques for receiver spatial diversity systems considered in the study are selection combining (SC), equal gain combining (EGC), and the maximum ratio combining (MRC). The bit error rate (BER) performance of the OWC system operating in weak oceanic turbulence is investigated by calculating the Gaussian beam's turbulence-induced scintillation index and the received optical intensity. It is found that the receiver spatial diversity techniques, especially EGC and MRC, are very effective for reducing the BER of an OWC system in weak oceanic turbulence. Furthermore, the BER performance of the underwater OWC system sees an improvement with an increase in the number of photodetectors or a decrease in the level of oceanic turbulence. Moreover, an improvement in the photodetector responsivity or a reduction in the system's noise factor contributes to achieving a favorable BER performance.
Detection and Classification of Femoral Neck Fractures From Plain Pelvic X-Rays Using Deep Learning and Machine Learning Methods
(Turkish Assoc Trauma Emergency Surgery, 2025) Sevinc, Huseyin Fatih; Ureten, Kemal; Karadeniz, Talha; Gultekin, Gokhan Koray
Background: Femoral neck fractures are a serious health concern, particularly among the elderly. The aim of this study is to diagnose and classify femoral neck fractures from plain pelvic X-rays using deep learning and machine learning algorithms, and to compare the performance of these methods. Methods: The study was conducted on a total of 598 plain pelvic X-ray images, including 296 patients with femoral neck fractures and 302 individuals without femoral neck fractures. Initially, transfer learning was applied using pre-trained deep learning models: VGG-16, ResNet-50, and MobileNetv2. Results: The pre-trained VGG-16 network demonstrated slightly better performance than ResNet-50 and MobileNetV2 for detecting and classifying femoral neck fractures. Using the VGG-16 model, the following results were obtained: 95.6% accuracy, 95.5% sensitivity, 93.3% specificity, 95.7% precision, 95.5% F1 Score, a Cohen's kappa of 0.91, and the Receiver Operating Characteristic (ROC) curve of 0.99. Subsequently, features extracted from the convolution layers of VGG-16 were classified using common machine learning algorithms. Among these, the k-nearest neighbor (k-NN) algorithm outperformed the others and exceeded the accuracy of the VGG-16 model by 1%. Conclusion: Successful results were obtained using deep learning and machine learning methods for the detection and classification of femoral neck fractures. The model can be further improved through multi-center studies. The proposed model may be especially useful for physicians working in emergency departments and for those not having sufficient experience in evaluating plain pelvic radiographs.
Numerical Investigation for Enhancement of Heat Transfer in the Cooling Water Jacket of CI Engine
(Taylor & Francis inc, 2025) Altug, Hakan; Yapici, Ekin Ozgirgin
Diesel engines are essential in heavy industries and agriculture, especially in vehicles like tractors that operate under challenging conditions, often causing engine faults. Effective thermal management systems are vital for faultless operation preventing overheating, extending engine life, reducing emissions, and improving efficiency. The core of these systems is the water jacket around the cylinder head, which regulates temperatures, facilitates lubrication, prevents friction-related faults, increase durability and thermal performance of the engine. Computational Fluid Dynamics techniques are crucial for analyzing engine thermal behavior and designing cooling systems with complex flows. This study simulates the engine block's temperature distribution under extreme conditions to prevent overheating and improve thermal performance. Geometrical modifications, such as optimizing outlet water ports are employed to achieve enhanced thermal performance by reducing the temperature of coolant. 3D model of the engine block is developed using STAR CCM+ to calculate water temperatures, flow rates and outlet pressures. Numerical validation is conducted with a test bench, and three geometric improvements are analyzed for temperature distribution and heat transfer coefficient. Results showed that, 6.2% improvement on thermal performance is achieved based on the average coolant temperatures and 10% enhancement is achieved in terms of heat transfer coefficient values.
Pressure and Temperature Dependence of the Dielectric Properties in Barium Titanate
(Indian Academy of Sciences, 2025) Kiraci, Ali; Yurtseven, Hamit
Temperature and pressure dependences of the soft-mode frequency (omega) and the dielectric constant (epsilon) are studied for the tetragonal-cubic transition (T-C = 395 K) in BaTiO3. We find that variations of the frequency and the dielectric constant with the temperature (pressure) are related to each other linearly close to the phase transition in this ferroelectric material. Instead of the Curie-Weiss behaviour of the dielectric constant, the critical behaviour of both soft-mode frequency and the dielectric constant is expressed by the power-law formulae, and the critical exponents are determined using the observed data from the literature. Our predicted frequencies of the soft mode at various pressures and temperatures, can be examined by the experimental measurements close to the tetragonal-cubic transition in BaTiO3.
Integrating the Seljuk Cultural Layer Into Contemporary Life: The Case of Niğde Historic City Center
(Istanbul Univ, Research Inst Turkology, Dept Art History, 2025) Yavascan, Emel Efe; Urak, Zehra Gediz
Historic city centers today serve as urban memory sites reflecting the "spirit of place" (genius loci) through their underground and aboveground historical layers, cultural richness, and unique identities. However, these multi-layered historic centers are increasingly turning into areas of urban decay due to the physical and functional deterioration of cultural assets, socio-cultural and economic degradation, and various conservation problems. In the case of Ni & gbreve;de, it has been identified that conservation practices have failed to consider the historical layers both above and below ground, which constitutes a major problem addressed in this study. The study area, perceived by locals as a hill, has long been characterized as a declining zone. The aim of this study is to analyze and map the Seljuk period layer within the Ni & gbreve;de Historic City Center and to develop proposals for its integration into contemporary conservation practices. Research findings indicate that the Seljuk period was the most significant era in the city's historical development, thus this layer was prioritized. Another objective is to contribute to the conservation and integration of other historical layers into daily life by setting an example. In this context, proposals have been developed for the sustainable conservation of the aboveground and underground heritage of the Seljuk period.
Retraction: Ali Et Al. Finite Element Study of Magnetohydrodynamics (MHD) and Activation Energy in Darcy-Forchheimer Rotating Flow of Casson Carreau Nanofluid (Vol 8, 1185, 2020)
(MDPI, 2025) Ali, Bagh; Rasool, Ghulam; Hussain, Sajjad; Baleanu, Dumitru; Bano, Sehrish
The Role of Cultural Heritage in Resilience Planning: Evidence From 100 Resilient Cities
(Firenze Univ Press, 2025) Altay-Kaya, Deniz; Yesilbag, Damla
As a container of accumulated experiences, cultural heritage connects past, present and future by transmitting knowledge to future generations through tangible/intangible assets. With this potential, cultural heritage can significantly contribute to community resilience, yet available resilience strategy documents place limited emphasis on cultural heritage. Based on this observed lack of systematic consideration, this paper analyses the resilience strategy documents presented in the 100 Resilient Cities Programme, and discerns six approaches towards cultural heritage, namely ignorance, economic development tool, identity construction, social component, physical integration tool, and comprehensive consideration. The paper discusses further ways cultural heritage can enhance community resilience.
Erken Cumhuriyet Dönemi Koruma ve Eğitim Vizyonuna Dair Bir Belge: Antikiteler ve Tarihi Eserlerden Derslerde Nasıl İstifade Edileceği Hakkında Andıç
(Hacettepe University, 2025) Önge, M.
Public consciousness for the conservation of the cultural heritage had been one of the most significant problems of Turkey hitherto. The founders of the republic, the intellectuals and the statesmen, who knew that the ignorance is the major cause of this problem, proposed the use of the cultural heritage of all types in the history lessons as the course material. This practice took place in the curriculum of the schools for the first time in 1926. In order to define its method better, a guidebook with the title “The Memorandum on the Usage of Antiquities and Historical Artifacts in the Courses”, is published in 1935, addressing the teachers. This guidebook, which was strangely named as “memorandum”, focuses on the idea of creating heritage conservation awareness in the public by making school age teenagers understand and embrace their cultural heritage. In this context, being completely different from the present-day authoritarian attitudes, the memorandum should be accepted as a significant document, which define a conservation attitude socializing heritage conservation by public education. This document also contains the evidences, which are related to the changes in terminology for defining cultural heritage in Türkiye, with respect to the changing attitudes and ways of understanding. Although it is not known how it had emerged, it is very probable that the memorandum was a part of the series of developments relating cultural heritage conservation in Türkiye, during the 1930’s. The memorandum text was consisting of twenty-four articles. The teachers were being instructed on how they are going to use the cultural heritage of all kinds in the courses, how they are going to make the cultural heritage meaningful for the students and make them enjoy the cultural heritage. It is noteworthy that the text contains application proposals like homework on the cultural heritage examples and establishment of school museums. Although the memorandum is an outdated document, the topics in it have timeless special importance. Therefore, the memorandum can be accepted as the expression of a cultural heritage attitude beyond its age. In this study, it is aimed to carry out extensive research on the memorandum. The memorandum is analyzed with respect to the heritage conservation related developments of its period and its importance is discussed in terms of its relation to present day conservation attitudes. In addition to being valuable as a document describing the conservation approaches of the early Republican Period, it has been revealed that the memorandum is up-to-date in terms of its content and an expression of the willing approach to conservation of its period. This study is prepared by using written and live sources. © 2025, Hacettepe University. All rights reserved.
Uygulama Yaşam Döngüsü Yönetim Araçlarının Verimini Arttırmak için Ciddi Oyun Uygulaması
(CEUR-WS, 2017) Üsfekes, C.; Yilmaz, M.; Tüzün, E.
Application lifecycle management aims to provide higher productivity using a set of tools for software development processes. It supports all processes from requirement analysis to deployment. This productivity is possible with software developers when they perform their tasks without losing motivation. If software developers can choose the optimum tasks, their productivity can increase. In this article an auction market and reward mechanism is developed by using algorithmic game theory and the studies on development software application.
Atıf - Scopus: 6
A New Companding Technique for PAPR Reduction in OFDM Communication Systems
(2011) Gazi, O.
One of the major disadvantages of OFDM communication systems is their high peak-to-average power ratio (PAPR) which degrades system performance when nonlinear power amplifiers are employed. Among the proposed PAPR techniques companding is favorable due to its simplicity and easy of implementation. In this article, using the arctangent function we propose a new compading technique for PAPR reduction. We compare the proposed technique to the previously suggested exponential companding, and μ-law companding methods. Via computer simulations it is verified that the proposed technique is better than exponential and μ-law companding methods for PAPR reduction. © 2011 HTE.
Hyers-Ulam Stability of Fractional Stochastic Differential Equations With Random Impulse
(Comenius Univ, 2022) Varshini, S.; Banupriya, K.; Ramkumar, K.; Ravikumar, K.; Baleanu, D.
The goal of this study is to derive a class of random impulsive fractional stochastic differential equations with finite delay that are of Caputo-type. Through certain constraints, the existence of the mild solution of the aforementioned system are acquired by Kransnoselskii's fixed point theorem. Furthermore, through Ito isometry and Gronwall's inequality, the Hyers-Ulam stability of the reckoned system is evaluated using Lipschitz condition.
Life Cycle Assessment of Geopolymer Materials Utilizing Construction and Demolition Waste
(Academic Press Inc Elsevier Science, 2025) Unsal, Zeynep; Ekinci, Mehmet Ozkan; Ilcan, Huseyin; Sahin, Oguzhan; Selcuk, Seda; Sahmaran, Mustafa
This study assessed the environmental impacts of construction and demolition waste (CDW)-based geopolymers. For analysis, the cradle-to-gate system boundary was established. Two different geopolymer mixtures were evaluated: one composed entirely of CDW-based precursors-(CDW100), and another incorporating supplementary cementitious materials-(SCMs) as a 20 % replacement of CDW-based precursors-(CDW80SCM20). Raw materials were sourced from a diverse range of demolition waste. NaOH and Ca(OH)2 were employed as activators. Additionally, a cementitious mixture with comparable strength was included in the analysis as a benchmark for comparison with the geopolymers. The results of the impact analyses revealed that CDW80SCM20 had a greater environmental impact across various categories compared to CDW100. The relatively higher environmental impacts of the CDW80SCM20 mixture are largely attributed to the transport-related environmental burdens associated with the inclusion of SCMs. The largest differences were for land occupation and global warming, at 30.8 % and 16.9 %, respectively. Moreover, the results indicated that the environmental impacts of the CDW-based mortars were significantly lower than those of the cementitious system, with the exception of aquatic eutrophication and ozone layer depletion. The increase in ozone layer depletion is mainly associated with the production of NaOH via the chlor-alkali process, which contributes to emissions affecting stratospheric ozone. The advantages of geopolymers in terms of environmental impact made it possible to reduce the effects of global warming by 48.1 %, aquatic acidification by 22.1 %, land occupation by 45.2 %, and nonrenewable energy consumption by 1.83 %. However, aquatic eutrophication and ozone layer depletion were found to be higher compared to cementitious mortar.

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