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Öğe Diffeomorphism invariance breaking in gravity and cosmological evolution(Springer, 2025) Aydemir, Ufuk; Elbistan, MahmutDiffeomorphism invariance breaking has been investigated in the literature in several contexts, including emergent General Relativity (GR). If GR emerges from an underlying theory without diffeomorphism invariance, there may be small violations of this symmetry at low energies. Since such small violations should not cause instabilities in cosmological evolution, it is a suitable framework for examining such symmetry-breaking effects. In this paper, the cosmological evolution with broken diffeomorphism invariance is investigated in the (modified) FLRW spacetime in the effective theory framework. The GR Lagrangian is augmented with all diffeomorphism-breaking but Lorentz-invariant terms in the leading order, namely, those involving two derivatives. The magnitudes of (minor) violations are kept general modulo the conditions arising in the linearized theory. The analytic solutions of the scale factor in the full non-linear theory for the single-component universes are attempted; the radiation and vacuum solutions are found analytically, whereas the matter solution is worked out numerically since an analytic solution does not exist in the required form. It is observed that the solutions smoothly connect to those of GR in the limit of vanishing symmetry-breaking. The more realistic, two-component, and three-component universes are numerically studied, and no signs of singular behavior are observed: minor diffeomorphism-violating modifications to GR at the level of two derivatives do not cause instabilities in the basic cosmological evolution.Öğe Trajectory Generation and Control for UAVs Using Quintic PH Curves and Kolmogorov-Arnold Networks (KANs)(Ieee, 2025) Ciftci, Fatma Senguler; Oniz, YesimThis paper presents a novel methodology that utilizes quintic Pythagorean-Hodograph (PH) curves for trajectory generation of unmanned aerial vehicles (UAVs) and Kolmogorov-Arnold Networks (KANs) for tracking problem. PH curves enable exact arc length computation and ensures smooth transitions in positions, velocities, and accelerations throughout the trajectory. The UAV's movements along the generated trajectory are regulated by KAN-based controllers. A separate controller is designed for each axis. We validate through simulations, indicating that a 40% improvement in tracking accuracy can be attained with KANs over conventional multilayer perceptrons (MLPs) under wind disturbances.Öğe Karachay-Balkar converb clauses(Harrassowitz Verlag, 2024) Gurer, AsliThis study investigates the internal and external syntax of {-(I)b) converb clauses in the Karachay-Balkar variety spoken in Konya, Turkey. It proposes that (i) converb clauses with {-(1)b) do not form a homogeneous group, (ii) the different and same-subject {-(I)b) con- verbs are not reduced and can include CP-level projections, (iii) the external syntax of the converbs differs, and converbs can attach at the CP, TP, or VP level, (iv) verb forms in {-(I)b), as predicates in finite clauses, express postterminality, and resultatives.Öğe An exploratory study of dialogic communication on mobile gaming company websites: The Turkish context(Scoala Natl Studii Politice Adm - Snspa, Fac Cominicare Realti Publice, 2025) Meric, Emre; Cakici, Zindan; Goncu, Barika; Dogan, SahikaDialogic communication remains an essential strategy for companies to build ways to interact with the relevant publics in the most effective and ethical approach. The current study aims to explore the dialogic communication potential of mobile gaming companies' websites via quantitative content analysis. The sample includes the websites of international mobile gaming companies that virtually communicate with their visitors in English as the primary language. The sample includes websites of mobile gaming companies producing the most popular games among Turkish gamers. Findings indicate that there is still room for such companies to increase their potential for dialogic communication with mobile gamers via their websites by increasing user interaction and enhancing user experience. Given the absence of research on dialogic communication strategies in mobile gaming company websites, this study provides foundational insights for both scholars and practitioners.Öğe Endogenous and imported populism vs local citizenship in marginalised and remote places of Europe(Policy Press, 2025) Kaya, Ayhan; Krasteva, Anna; Membretti, Andrea[Abstract Not Available]Öğe Energy Management System Strategy Evaluation for E-Vehicles Using Proportional Pythagorean Fuzzy AHP(Old City Publishing Inc, 2026) Otay, Irem; Sari, Irem Ucal; Tolga, A. Cagri; Cebi, Selcuk; Onar, Sezi Cevik; Oztaysi, BasarThe shift from conventional vehicles to electric vehicles (EVs) is essential for sustainability. Energy management strategies play a crucial role in this transition, as they affect battery performance, extend lifespan, and ensure cost-effectiveness. This study evaluates energy management system (EMS) strategies for EVs using the Proportional Pythagorean Fuzzy Analytical Hierarchy Process (PPF-AHP) to prioritize decision criteria. To achieve this, a decision model is constructed involving four main criteria-sustainability and resilience, cost efficiency, performance and reliability, and competitiveness-as well as sixteen sub-criteria. Then, pairwise evaluations from five experts are collected and aggregated leading to the prioritization of decision criteria. In order to show the robustness of the methodology, the PPF-AHP results are compared with Buckley's Fuzzy AHP and Decomposed Fuzzy AHP.Öğe The Derivation of System Parameters for a Ground Source Heat Pump (GSHP)(Int Journal Renewable Energy Research, 2025) Camdali, Unal; Tunc, Murat; Erdem, Mehmet Emre; Tuncel, Erhanwell known the widespread use of nonrenewable energy sources such as fossil fuels cause environmental problems. Ground source heat pumps (GSHP) are highly efficient renewable energy system used for heating and cooling where cool deep ground source is used for higher efficiency. In this study, a new simulation model has been developed and used for heat pumps for low global warming potential (GWP) refrigerants such as R134a and validated by the experimental data. Also, the system parameters of a GSHP are obtained theoretically for heating and cooling modes of a building, located in Bolu City, Turkey. For this purpose, non-linear equations are determined by considering GSHP models in relevant literatures for heating and cooling capacity of 1.4 and 2.2 kW respectively for a building having dimensions as 4.4 m x 2.2 m x 3.6 m. In this respect, COPs for heating and cooling are calculated and obtained results are depicted. An algorithm is generated to design the R134a refrigerant heat exchanger to maximize the efficiency.Öğe Beyond binary: University student perceptions of online, hybrid and face-to-face learning, post-pandemic in Türkiye(Western Australian Inst Educational Research Inc, 2025) Aydin, Oya TamtekinBetween 2020 and 2024, higher education students experienced diverse instructional methods. The Covid-19 pandemic triggered a rapid transition to online education in 2020, which persisted in many regions until 2022. By then, universities largely returned to face-to-face instruction without consulting students' preferences. Although this was initially welcomed as normalcy, students who had experienced online education began questioning the necessity of daily campus attendance. This study, conducted in Istanbul, T & uuml;rkiye, explores whether students would have preferred changes in delivery modes if given a choice, their preferences for face-to-face, online, or hybrid education, and the factors shaping these views. A mixed-methods approach was employed, combining surveys and semi-structured interviews. Of 232 students invited, 195 completed the survey, and 37 participated in interviews. All procedures were voluntary and anonymous. Survey and interview results revealed conflicting opinions. Students emphasised the benefits of both online and face-to-face education, but often followed these with reservations, reflecting an internal dilemma. The frequent use of but in their statements illustrates their struggle to fully align with either model. Rather than rejecting traditional methods or fully embracing online alternatives, most favoured hybrid systems. Notably, students reframed work-life balance as education-life-work balance. Overall, the study signals a growing demand for adaptive teaching and offers insights for policymakers seeking to align higher education with contemporary needs.Öğe Fast Contiguous Somatic Hypermutations for Single-Objective Optimisation and Multi-Objective Optimisation Via Decomposition(Assoc Advancement Artificial Intelligence, 2025) Corus, Dogan; Oliveto, Pietro S.; Yazdani, DonyaSomatic Contiguous Hypermutations (CHM) are a popular variation operator used in artificial immune systems for optimisation tasks. Theoretical studies have shown that CHM operators can lead to considerable speed-ups in the expected optimisation time compared to the traditional standard bit mutation (SBM) operators used in evolutionary computation for both single-objective and multi-objective problems where it is advantageous to mutate large contiguous areas of the genotype representing the candidate solutions. These speed-ups can make the difference between polynomial and exponential runtimes, but come at the expense of the CHM operator being considerably slower than the SBM operator in easy hillclimbing phases of the optimisation process, when small areas of the genotype have to be mutated for progress to be made. In this paper we present a Fast CHM operator that is asymptotically just as fast as traditional SBM for hillclimbing yet maintains the efficacy of the standard CHM operator when large jumps in the search space are required to make progress efficiently. We demonstrate such efficacy on all applications where CHM has been previously studied in the literature.Öğe The General (?, ?)-metrics with Quadratic Curvatures(Tarbiat Modares Univ, Acecr, 2025) Gabrani, Mehran; Rezaei, Bahman; Sevim, Esra SengelenIn this paper, we consider the Riemannian curvature of one of the most important metric in Finsler geometry called general (alpha, beta)-metrics, where alpha is a Riemannian metric and beta is 1-form. We give a complete classification of the metrics to be R-quadratic and Ricci-quadratic.Öğe Synthesis and Characterization of Cu-Co Substituted Strontium Hexaferrite for Magnetic Applications(Kaunas Univ Tech, 2024) Ertug, BurcuIn this study, the structural and magnetic characterizations of a series of SrCoxCuxFe12-2xO19; 0.0 <= x <= 0.5 samples, which were produced by the conventional ceramic method, were carried out. The structure was examined by X-ray diffraction (XRD) technique and optical microscopy. A vibrating sample magnetometer (VSM) was used to characterize the ferrimagnetic properties. XRD patterns confirmed the presence of a single phase as Sr-hexaferrite while there were not any peaks of unreacted Fe2O3 phase. The densities varied between 92 - 98 %. XRD patterns of the Sr-hexaferrite samples were slightly modified because of the co-substitution of Cu-Co; however, the magnetic properties changed remarkably. The sample with Cu-Co of x = 0.1 content had the highest saturation magnetization (33.52 emu/g), remanence (19.74 emu/g), and coercivity (4.3 kOe). The synthesized magnetic samples were found to be suitable for the development of attractive ferrimagnetic properties for the current ferrite magnets.Öğe Continuous Intuitionistic Fuzzy AHP & CODAS Methodology for Automation Degree Selection(Old City Publishing Inc, 2024) Alkan, Nursah; Otay, Irem; Gul, Alize Yaprak; Demir, Zeynep Burcu Kizilkan; Dogan, OnurThe automotive industry's evolution thrives on technological innovation, prioritizing efficiency, safety, and sustainability. Recent improvements in autonomous driving and IoT integration have revolutionized vehicle design, safety, and maintenance with different automation degrees from partial human control to full automation. Selecting these automation degrees involves complicated Multi-Criteria Decision-Making (MCDM) encompassing technical feasibility, societal impact, and regulatory compliance. Utilizing Analytic Hierarchy Process (AHP) and Combinative Distance-Based Assessment (CODAS) offers a structured framework to navigate these complexities. AHP establishes criteria importance, while CODAS handles uncertainties, enabling informed decisions balancing technology with ethical, societal, and regulatory considerations. Fuzzy extensions further refine these methodologies, empowering the industry to adeptly address subjective perceptions and ambiguous data, enhancing the decision-making framework for automotive technology evolution. This paper navigates the intricate landscape of automation degree selection within the automotive industry evolution, employing a structured approach merging fuzzy AHP and fuzzy CODAS methods by utilizing Continuous Intuitionistic Fuzzy Set (CINFUS). This approach not only brings a new perspective to autonomous vehicles but also highlights the importance of choosing the right automation degree. Moreover, a sensitivity analysis involved adjusting the weights assigned to different criteria within the Continuous Intuitionistic Fuzzy (CINFU) AHP framework. By systematically altering these weights and observing their impact on the final automation degree selection, decision-makers can understand the sensitivity of the chosen automation degree to changes in priority among criteria.Öğe The investigation of fermented food consumption on gastrointestinal symptoms: a cross-sectional study in university students(Peerj Inc, 2025) Seven Avuk, Hande; Aydin, Oyku; Kocatepe, Neslihan; Sahin, Sude Melis; Akdogan, Irem; Cavus, EserBackground Fermented foods (FFs) are a valuable source of live microorganisms that can enhance human health, particularly gastrointestinal health, akin to probiotics. This study investigated the relationship between FFs consumption habits and gastrointestinal system findings in university students. Methods A cross-sectional anonymous survey included 546 university students, collecting data on sociodemographic characteristics, the Gastrointestinal Symptom Rating Scale (GSRS), and the Bristol Stool Form Scale (BSFS). FFs consumption habits were recorded using a food frequency questionnaire. Results Results showed that the average GSRS score was 33.66 +/- 16.89. According to the BSFS, 15% of students experienced constipation, 72.7% had moderate stool consistency, and 12.3% had diarrhea. Notably, kefir, vinegar, and sourdough bread were never consumed by 56.8%, 44.3%, and 41.9% of students, respectively. Significant differences were found between the frequency of yogurt, kefir, vinegar, cheese, pickle consumption, and gastrointestinal symptoms (p < 0.05). Students with normal stool consistency had fewer dyspepsia, abdominal pain, reflux symptoms, and overall gastrointestinal symptoms than those with constipation (p < 0.05). Conclusion The study concludes that FFs such as yogurt, cheese, pickles, and kefir may offer health benefits, reducing symptoms of reflux, dyspepsia, abdominal pain, and general gastrointestinal issues in young adults.Öğe PLASMA COENZYME Q10 LEVELS OF INDIVIDUALS WITH NEWLY DIAGNOSED TYPE 2 DIABETES AND DIABETES INDIVIDUALS WITH ADVANCED MICROALBUMINURIA: A COMPARATIVE STUDY(Nobel Ilac, 2024) Yildirim, Osman; Demirel, Birsen; Guendogan, Erdal; Avuk, Hande SevenObjective: Diabetes is a chronic disease that causes the development of microalbuminuria. CoQ10 deficiency is common in people with type 2 diabetes. This study aims to evaluate whether coenzyme Q10 (CoQ10) levels are a risk factor for diabetes and microalbuminuria in newly diagnosed diabetes and advanced microalbuminuria. Material and Method: The study was conducted with patients who came to the internal medicine outpatient clinic. Plasma CoQ10 and malondialdehyde (MDA) values of 90 people in total, including 30 people in each group, newly diagnosed Type 2 diabetes (Group D), diabetes mellitus with microalbuminuria (Group M), and the control group (Group C) were examined. Results: There was no difference between plasma CoQ10 and MDA levels of newly diagnosed type 2 diabetes patients and those with microalbuminuria (p>0.05). There was a negative correlation between CoQ10 and fasting glucose and HbA1c in all groups (p<0.05). A positive correlation was observed between CoQ10 and MDA (p<0.05). CoQ10 level of the control group was found to be higher than Group D and M (p<0.05); the difference between Group M and Group D was not significant (p>0.05). As a result of regression analysis, increasing the CoQ10 value was found to have a protective effect on the risk of diabetes (95 %CI: p=0.005). Conclusion: This study showed that individuals with low blood sugar and HbA1c had high CoQ10 levels. We think that CoQ10 can be considered a risk factor for diabetes, and further studies examining total CoQ10 and ubiquinol/ ubiquinone ratio would be beneficial.Öğe Music Videos as Protest Communication: The Gezi Park Protest on YouTube(Routledge, 2025) Jenzen, Olu; Erhart, Itir; Eslen-Ziya, Hande; Gucdemir, Derya; Korkut, Umut; McGarry, AidanThis chapter explores the relevance of the protest song as political communication in the Internet era. Focusing on the prolific and diverse YouTube music video output of the Gezi Park protest of 2013, we explore how digital technologies and social media offer new opportunities for protest music to be produced and reach new audiences. We argue that the affordances of digital media and Internet platforms such as YouTube play a crucial part in the production, distribution and consumption of protest music. In the music videos, collected from Twitter, activists use a range of aesthetic and rhetorical tools such as various mash-up techniques to challenge mainstream media reporting on the protest, communicate solidarity, and express resistance to dominant political discourse.Öğe Pet Naming Practices in Turkey: Cats vs. Dogs(Univ Pittsburgh, Univ Library System, 2025) Ketrez, F. NihanPet-naming practices reflect the attitudes of pet owners towards their pets and their place in their lives and society. In the US and other western countries, pet animals are often given names that are commonly used for humans. This trend is frequently considered an endorsement of family membership granted to pet animals. In this study, cat and dog names reported by Turkish-speaking cat and dog owners were examined; and the proportion of human vs. non-human, as well as foreign vs. domestic names were investigated. It was observed that cats were more likely to be given human names than dogs. Cats also received more traditional Turkish names, while dogs were more likely to be given foreign or more modern human names. The results are evaluated in relation to the status of pet dogs in the modernization and secularism of modern Turkey. Historically, dogs were granted limited access to homes because of their ritually impure status in Islam. With the modernization and westernization trends, however, having a dog as a pet became a symbol of modernity. The differential pet-naming trends reported in the present study complement such observations regarding the status of cats vs. dogs in modern Turkey.Öğe Introduction: The Aesthetics of Global Protest: Visual Culture and Communication(Routledge, 2025) McGarry, Aidan; Erhart, Itir; Eslen-Ziya, Hande; Jenzen, Olu; Korkut, UmutProtest movements are struggles to be seen and to be heard. In the last 60 years protest movements around the world have mobilized against injustices and inequalities to bring about substantial sociocultural, sociopolitical, and socio-economic changes. Whilst familiar repertoires of action persist, such as strikes, demonstrations, and occupations of public space, the landscape is very different from 60 years ago when the so-called 'new social movements' emerged. We need to take stock of the terrain of protest movements, including dramatic developments in digital technologies and communication, the use of visual culture by protestors, and the expression of democracy. This chapter introduces the volume and explains how aesthetics of protest are performative and communicative, constituting a movement through the performance of politics.Öğe Posttraumatic Stress Disorder-Related Mental Health Problems and Risk Factors After an Earthquake(Aves, 2025) Aker, Tamer; Onder, EceEarthquakes can have a substantial impact on communities, leading to severe economic losses, structural damage, casualties, and displacement, as well as adverse psychological effects on survivors. Previous studies have highlighted a broad spectrum of adverse psychological effects following disasters, such as sleep disturbances, emotional distress, depression, suicidal thoughts, anxiety, posttraumatic stress disorder (PTSD). Posttraumatic stress disorder is particularly common among disaster survivors. It is characterized by the emergence of specific symptoms following direct exposure (experiencing a traumatic event firsthand or witnessing it happen to others) or indirect exposure (learning about a traumatic event involving loved ones or repeatedly being exposed to distressing details of the event). Disasters, crises, and traumas are difficult life experiences that require individuals to seek support. It is crucial to identify key factors such as individuals' location, emotional state, and their specific needs during these times to provide effective assistance. Addressing these aspects is essential in preventing trauma from worsening or becoming more entrenched. Post-earthquake psychosocial support should include comprehensive, long-term, and sustainable interventions to improve the mental health of both individuals and society. The aim of this article is to evaluate PTSD and related mental health issues following earthquakes.Öğe The 1/c expansion of general relativity in a 3(Tubitak Scientific & Technological Research Council Turkey, 2026) Elbistan, MahmutWe study the 1/c expansion of general relativity within a formulation that is compatible with both the Arnowitt-Deser-Misner and the Kol-Smolkin decompositions. The Einstein-Hilbert action takes a common form for those decompositions as they are dual to each other. We first develop a method to expand this generic form without choosing a particular slicing and then push the expansion up to c-3 order within this novel approach. Next, we apply our technique to the Arnowitt-Deser-Misner decomposition and expand it up to c-3 order explicitly. In order to demonstrate the applicability of our method and to highlight the duality at the level of expansion, we also perform the expansion in the Kol-Smolkin decomposition up to c-1 order. Lastly, we make some all-order observations.Öğe Regulation of Digital Platforms in Turkish Law The E-Commerce Law and the Draft Competition Law(Routledge, 2025) Sanli, Kerem Cem; Dogan, Cihan[Abstract Not Available]
