Scopus İndeksli Yayınlar Koleksiyonu
Permanent URI for this collectionhttps://hdl.handle.net/20.500.12416/8651
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Article Δ-Gronwall Dynamic Inequalities and Their Applications on Time Scales(Mdpi, 2022) El-Deeb, Ahmed A.; Baleanu, Dumitru; Awrejcewicz, JanIn this article, with the help of Leibniz integral rule on time scales, we prove some new dynamic inequalities of Gronwall-Bellman-Pachpatte-type on time scales. These inequalities can be used as handy tools to study the qualitative and quantitative properties of solutions of the initial boundary value problem for partial delay dynamic equation.Article Health Capital and a Sustainable Economic-Growth Nexus: a High-Frequency Analysis During Covid-19(Mdpi, 2024) Sungur, Nazli Ceylan; Akdogan, Ece C.; Gokten, SonerThe recent COVID-19 pandemic effectively concretized the vitality of health expenditure and the economic-growth nexus, and the threat of new pandemics make re-examining this relationship a necessity. Consequently, this paper focuses on this nexus for developed OECD countries, paying particular attention to the effects of the COVID-19 pandemic. The use of stock indices as proxy variables for health expenditure and economic growth enabled the examination of this nexus by using high-frequency data and financial econometric techniques, specifically via rolling correlation and bivariate GARCH analyses. The data span 1170 observations between 15 May 2018 and 11 November 2022. Since the research period overlaps with the outbreak of Ukraine-Russia war, additional insights are obtained regarding the effects of the war as well. It was found that an increase in health expenditure leads to a delayed increase in economic growth even in the short term, and this relationship mainly develops during crises such as epidemics, wars, supply chain breakdowns, etc., for developed OECD countries. Given the aging population of developed countries, which will probably deteriorate the health status of those countries in the near future, the increasing political tensions around the globe and the considerations of a global recession highlight the importance and the inevitability of investments in health capital for developed countries as well.Article Citation - WoS: 1Citation - Scopus: 1Building Occupant Energy Labels (Oel): Capturing the Human Factors in Buildings for Energy Efficiency(Mdpi, 2025) Harputlugil, Timucin; de Wilde, PieterOccupancy is one of the primary contributors to the energy performance gap, defined as the difference between actual and predicted energy usage, in buildings. This paper limits its scope to residential buildings, where occupant-centric consumption often goes unaccounted for in standard energy metrics. This paper starts from the hypothesis that a simple occupant energy efficiency label is needed to capture the essence of occupant behaviour. Such a label would help researchers and practitioners study a wide range of behavioural patterns and may better frame occupant interventions, potentially contributing more than expected to the field. Focusing on the residential sector, this research recognises that the complexity of occupant behaviour and its links to different scientific calculations requires that researchers deal with several intricate factors in their building performance assessments. Moreover, complexity arising from changing attitudes and behaviours-based on building typology, social environment, seasonal effects, and personal comfort levels-further complicates the challenge. Starting with these problems, this paper proposes a framework for an occupant energy labelling (OEL) model to overcome these issues. The contribution of the paper is twofold. Firstly, the literature is reviewed in depth to reveal current research related to occupant behaviour for labelling of humans based on their energy consumption. Secondly, a case study with energy simulations is implemented in the UK, using the CREST tool, to demonstrate the feasibility and potential of OEL. The results show that labelling occupants may help societies reduce building energy consumption by combining insights from energy statistics, surveys, and bills gathered with less effort, and can assist decision-makers in determining the best match between buildings and occupants. While the focus of this study is on residential buildings, future research is recommended to explore the applicability of OEL in office environments, where occupant behaviour and energy dynamics may differ significantly.Article Citation - WoS: 6Citation - Scopus: 6Viscoelastic and Fatigue Performance of Modified Bitumen Using Polymer and Bio-Based Additives: a Comparative Study(Mdpi, 2025) Almusawi, Ali; Nasraldeen, Shvan Tahir; Albdairi, Mustafa; Norri, Hussein H.This study investigates the performance and viscoelastic characteristics of unmodified and modified bitumen using Performance Grading, Frequency Sweep, and Linear Amplitude Sweep tests. The bitumen modifications include styrene-butadiene-styrene at 4% and 5%, animal bone powder at concentrations of 4%, 5%, and 6%, and waste cooking oil at 3%, 4%, and 5%. Performance Grading tests were conducted to evaluate the high-temperature performance of bitumen samples. Frequency Sweep tests were used to analyze the complex shear modulus and phase angle, providing insights into stiffness and elasticity. The Linear Amplitude Sweep tests assessed fatigue resistance by monitoring the degradation of the complex shear modulus under cyclic loading. Styrene-butadiene-styrene and animal bone powder significantly enhanced stiffness, elasticity, and fatigue resistance, with styrene-butadiene-styrene-modified samples achieving the highest performance grades and fatigue resistance. Waste cooking oil-modified bitumen reduces stiffness and fatigue resistance, indicating it primarily acts as a plasticizer. Styrene-butadiene-styrene and animal bone powder are effective modifiers for improving bitumen's mechanical and fatigue properties and are suitable for demanding applications. In contrast, waste cooking oil compromises structural performance despite its environmental benefits, making it less suitable for high-performance use.Article Citation - WoS: 2Citation - Scopus: 1Millimeter-Wave Sar Imaging for Sub-Millimeter Defect Detection With Non-Destructive Testing(Mdpi, 2025) Yalcinkaya, Bengisu; Aydin, Elif; Kara, AliThis paper introduces a high-resolution 77-81 GHz mmWave Synthetic Aperture Radar (SAR) imaging methodology integrating low-cost hardware with modified radar signal characteristics specifically for NDT applications. The system is optimized to detect minimal defects in materials, including low-reflectivity ones. In contrast to the existing studies, by optimizing key system parameters, including frequency slope, sampling interval, and scanning aperture, high-resolution SAR images are achieved with reduced computational complexity and storage requirements. The experiments demonstrate the effectiveness of the system in detecting optically undetectable minimal surface defects down to 0.4 mm, such as bonded adhesive lines on low-reflectivity materials with 2500 measurement points and sub-millimeter features on metallic targets at a distance of 30 cm. The results show that the proposed system achieves comparable or superior image quality to existing high-cost setups while requiring fewer data points and simpler signal processing. Low-cost, low-complexity, and easy-to-build mmWave SAR imaging is constructed for high-resolution SAR imagery of targets with a focus on detecting defects in low-reflectivity materials. This approach has significant potential for practical NDT applications with a unique emphasis on scalability, cost-effectiveness, and enhanced performance on low-reflectivity materials for industries such as manufacturing, civil engineering, and 3D printing.Article Citation - WoS: 7Citation - Scopus: 17Integrating Autonomous Vehicles (Avs) Into Urban Traffic: Simulating Driving and Signal Control(Mdpi, 2024) Almusawi, Ali; Albdairi, Mustafa; Qadri, Syed Shah Sultan MohiuddinThe integration of autonomous vehicles into urban traffic systems offers a significant opportunity to improve traffic efficiency and safety at signalized intersections. This study provides a comprehensive evaluation of how different autonomous vehicle driving behaviors-cautious, normal, aggressive, and platooning-affect key traffic metrics, including queue lengths, travel times, vehicle delays, emissions, and fuel consumption. A four-leg signalized intersection in Balgat, Ankara, was modeled and validated using field data, with twenty-one scenarios simulated to assess the effects of various autonomous vehicle behaviors at penetration rates from 25% to 100%, alongside human-driven vehicles. The results show that while cautious autonomous vehicles promote smoother traffic flow, they also result in longer delays and higher emissions due to conservative driving patterns, especially at higher penetration levels. In contrast, aggressive and platooning autonomous vehicles significantly improve traffic flow and reduce delays and emissions. Mixed-behavior scenarios reveal that different driving styles can coexist effectively, balancing safety and efficiency. These findings emphasize the need for optimized autonomous vehicle algorithms and signal control strategies to harness the potential benefits of autonomous vehicle integration in urban traffic systems fully, particularly in terms of improving traffic performance and sustainability.Article Engagement and Brand Recall in Software Developers: an Eye-Tracking Study on Advergames(Mdpi, 2024) Akcan, Duygu; Yilmaz, Murat; Gulec, Ulas; Ilgin, Hueseyin EmreAdvergames represent a novel product placement strategy that surpasses traditional advertising methods by fostering interaction between brands and their target audiences. This study investigates the unique engagement opportunities provided by video games, focusing mainly on the 'flow experience', an intensified state of immersion frequently encountered by players of computer games. Such immersive experiences have the potential to significantly influence a player's perception, offering a new avenue for advertisements to impact and engage audiences effectively. The primary objective of this research was to examine the influence of advergames on players who are deeply immersed in the gaming experience, with a specific focus on the subsequent effects on brand recognition over time. The study involved 44 software developers, who were evenly divided into two groups for the experiment. Both groups were exposed to an identical gaming environment with the task of locating a designated product within the game. However, one group interacted with an enhanced version of the game, which included additional stimuli-such as dynamic music, an engaging narrative, time constraints, a competitive leaderboard, and immersive voice acting-to intensify the gaming experience. The experiment strategically placed various products within the game, and their detectability was assessed using eye-tracking technology. Following gameplay, participants completed questionnaires that measured their experience with flow state and brand recall. The data were analyzed using the Mann-Whitney U test and correlation analysis to facilitate comparisons. The findings indicated that the product associated with the primary task achieved the highest recall rate between both groups. Furthermore, eye-tracking technology identified the areas in the game that attracted the most attention, revealing a preference for mid- and high-level placements over lower-level ones.Article Citation - WoS: 42Citation - Scopus: 46Fuzzy-Based Intelligent Model for Rapid Rock Slope Stability Analysis Using Qslope(Mdpi, 2023) Mao, Yimin; Chen, Liang; Nanehkaran, Yaser A.; Azarafza, Mohammad; Derakhshani, RezaArtificial intelligence (AI) applications have introduced transformative possibilities within geohazard analysis, particularly concerning the assessment of rock slope instabilities. This study delves into the amalgamation of AI and empirical techniques to attain highly precise outcomes in the evaluation of slope stability. Specifically, our primary objective is to propose innovative and efficient methods by investigating the integration of AI within the well-regarded Q(slope) system, renowned for its efficacy in analyzing rock slope stability. Given the complexities inherent in rock characteristics, particularly in coastal regions, the Q(slope) system necessitates adjustments and harmonization with other geomechanical methodologies. Uncertainties prevalent in rock engineering, compounded by water-related factors, warrant meticulous consideration during all calculations. To address these complexities, we present a novel approach through the infusion of fuzzy set theory into the Q(slope) classification, leveraging fuzziness to effectively quantify and accommodate uncertainties. Our approach employs a sophisticated fuzzy algorithm encompassing six inputs, three outputs, and 756 fuzzy rules, thereby enabling a robust assessment of rock slope stability in coastal regions. The implementation of this method capitalizes on the high-level programming language Python, enhancing computational efficiency. To validate the potency of our AI-based approach, we conducted preliminary tests on slope instabilities within coastal zones, indicating a promising initial direction. The results underwent thorough evaluation, affirming the precision and dependability of the proposed method. However, it is crucial to emphasize that this work represents a first attempt to apply AI to the evaluation of rock slope stability. Our findings underscore a high degree of concurrence and expeditious stability assessment, vital for timely and effective hazard mitigation. Nonetheless, we acknowledge that the reliability of this innovative method must be established through broader applications across diverse scenarios. The proposed AI-based approach's effectiveness is validated through a preliminary survey on a slope instability case within a coastal region, and its potential merits must be substantiated through broader validation efforts.Article Citation - WoS: 1Citation - Scopus: 2Task-Based Visual Attention for Continually Improving the Performance of Autonomous Game Agents(Mdpi, 2023) Ulu, Eren; Capin, Tolga; Celikkale, Bora; Celikcan, UfukDeep Reinforcement Learning (DRL) has been effectively performed in various complex environments, such as playing video games. In many game environments, DeepMind's baseline Deep Q-Network (DQN) game agents performed at a level comparable to that of humans. However, these DRL models require many experience samples to learn and lack the adaptability to changes in the environment and handling complexity. In this study, we propose Attention-Augmented Deep Q-Network (AADQN) by incorporating a combined top-down and bottom-up attention mechanism into the DQN game agent to highlight task-relevant features of input. Our AADQN model uses a particle-filter -based top-down attention that dynamically teaches an agent how to play a game by focusing on the most task-related information. In the evaluation of our agent's performance across eight games in the Atari 2600 domain, which vary in complexity, we demonstrate that our model surpasses the baseline DQN agent. Notably, our model can achieve greater flexibility and higher scores at a reduced number of time steps.Across eight game environments, AADQN achieved an average relative improvement of 134.93%. Pong and Breakout games both experienced improvements of 9.32% and 56.06%, respectively. Meanwhile, SpaceInvaders and Seaquest, which are more intricate games, demonstrated even higher percentage improvements, with 130.84% and 149.95%, respectively. This study reveals that AADQN is productive for complex environments and produces slightly better results in elementary contexts.Article Citation - WoS: 3Citation - Scopus: 4Monotonicity Results for Nabla Riemann-Liouville Fractional Differences(Mdpi, 2022) Mohammed, Pshtiwan Othman; Srivastava, Hari Mohan; Balea, Itru; Jan, Rashid; Abualnaja, Khadijah M.; Baleanu, DumitruPositivity analysis is used with some basic conditions to analyse monotonicity across all discrete fractional disciplines. This article addresses the monotonicity of the discrete nabla fractional differences of the Riemann-Liouville type by considering the positivity of ((RL)(b0)del(theta)g)(z) combined with a condition on g(b(0)+2), g(b(0)+3) and g(b(0)+4), successively. The article ends with a relationship between the discrete nabla fractional and integer differences of the Riemann-Liouville type, which serves to show the monotonicity of the discrete fractional difference ((RL)(b0)del(theta)g)(z).