Scopus İndeksli Yayınlar Koleksiyonu
Permanent URI for this collectionhttps://hdl.handle.net/20.500.12416/8651
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Article CFD and DEM Analysis of Cyclone Separator Performance: Implications of Cylinder-to Ratios for Sustainable Engineering(Springer Heidelberg, 2025) Ayli, Ece; Kocak, EyupThis research addresses a common industrial challenge: efficiently separating particles from gas using cyclone separators, a critical component for various applications in sustainable engineering. While several studies have focused on airflow within these separators, this research introduces a novel approach by combining two advanced simulation methods (CFD and DEM) to analyze how different cone heights in a cyclone separator impact its performance. This combined methodology enables the examination of particle movement within the separator, a critical aspect often overlooked in previous studies. By visualizing particle dynamics and analyzing them with DEM, the research underscores the importance of considering particle behavior for obtaining accurate results. Overall, this study enhances our understanding of cyclone separators through state-of-the-art simulations and empirical testing. By elucidating the complex airflow and the influence of geometric design on performance, practical recommendations are provided for the development of more efficient cyclone separators. These improvements can lead to enhanced particle separation and reduced energy consumption, offering significant benefits across multiple industries. The findings reveal that as the conical height-to-total height ratio (h/hc) increases, indicating a more pointed cone, there is a substantial increase in efficiency alongside a minimal and tolerable rise in pressure drop. For instance, at a velocity of 25 m/s, increasing the h/hc ratio from 0.33 to 3 results in a 0.7% reduction in pressure drop and a 14% efficiency increase, contributing to more sustainable operational practices.Article Improved Arithmetic Efficiency in TFHE Through Gate-Level Optimizations(Springer, 2025) Tasel, Faris Serdar; Saran, Ayse NurdanFully homomorphic encryption (FHE) enables computations to be performed directly on encrypted data without decryption, offering a promising solution for privacy-preserving applications, such as secure cloud computing, confidential machine learning, and encrypted analytics. However, one major drawback of FHE is the high computational cost of homomorphic operations, which slows down real-world implementations, making them impractical. This paper explores the implementation of arithmetic operations within the framework of Torus FHE (TFHE) and demonstrates the construction of gate-level optimization for fundamental operations such as addition, subtraction, negation, comparison, and multiplication on fixed-point numbers. Our work emphasizes optimizing arithmetic logic to reduce the number of bootstrapping operations, a critical factor in improving computational efficiency. Furthermore, we investigate the error rates associated with the proposed operations, providing valuable insight into their accuracy and practical applicability. This study contributes to developing more efficient and reliable arithmetic logic for privacy-preserving computations in FHE systems. The experimental results indicate that the proposed optimizations yield speedups of up to 2.27x for addition/subtraction, 3.55x for comparison, and 1.80x for multiplication operations.Article Citation - WoS: 2Comparing Hand-Based and Controller-Based Interactions in Virtual Reality Learning: Effects on Presence and Interaction Performance(PeerJ Inc, 2025) Saran, MuratVirtual reality (VR) holds significant promise for enhancing science education by providing immersive and interactive learning experiences. However, the optimal interaction modality within educational VR environments remains an open question. This study investigates the impact of hand-based vs. controller-based interaction on sixth-grade students' sense of presence and interaction performance in a VR science laboratory simulation. Fifty-four sixth-grade students were randomly assigned to either a hand-based interaction group or a controller-based interaction group. Participants completed three interactive science experiments (solar system, electrical circuits, and force/energy) within a virtual laboratory environment designed to mimic their school's physical lab. Presence was assessed using a validated Turkish adaptation of the Presence Questionnaire (PQ), while interaction performance was evaluated using a structured observation form completed by a school teacher. Independent samples t-tests and Mann-Whitney U tests were used to compare the presence and performance scores between the groups. Supplementary analyses explored the effects of gender and prior VR experience. Contrary to expectations, no significant differences were found in either presence (t(49.4) = -0.01, p = 0.992) or interaction performance (t(52) = -1.30, p = 0.199) between the hand-based and controller-based interaction groups. Both interaction modalities yielded comparable levels of self-reported presence and observed performance. However, an unexpected finding emerged regarding performance. A supplementary analysis revealed a significant main effect of gender on performance scores (F(1, 50) = 4.844, p = 0.032), independent of interaction type. Specifically, males demonstrated significantly higher performance than females. This study suggests that, for sixth-grade students engaging in these specific VR science simulations, hand-based and controller-based interactions are equally effective in terms of fostering presence and supporting interaction performance. These findings have practical implications for the design and implementation of VR learning environments, particularly in resource-constrained settings where the reduced maintenance and hygiene concerns associated with hand-based interaction may be advantageous.Article Citation - WoS: 30Citation - Scopus: 31Heat and Mass Transport Impact on MHD Second-Grade Fluid: A Comparative Analysis of Fractional Operators(Wiley, 2021) Rehman, Aziz Ur; Riaz, Muhammad Bilal; Akgul, Ali; Saeed, Syed Tauseef; Baleanu, DumitruThe effect of the magnetic flux plays a major role in convective flow. The process of heat transfer is accompanied by a mass transfer process; for instance, condensation, evaporation, and chemical process. Due to the applications of the heat and mass transfer combined effects in different fields, the main aim of this paper is to do a comprehensive analysis of heat and mass transfer of magnetohydrodynamic (MHD) unsteady second-grade fluid in the presence of ramped conditions. The new governing equations of MHD second-grade fluid have been fractionalized by means of singular and nonsingular differentiable operators. To have an accurate physical significance of imposed conditions on the geometry of second-grade fluid, the constant concentration with ramped temperature and ramped velocity is considered. The fractional solutions of temperature, concentration, and velocity have been investigated by means of integral transform and inversion algorithm. The influence of physical parameters and flow is analyzed graphically via computational software (MATHCAD-15). The velocity profile decreases by increasing the Prandtl number. The existence of a Prandtl number may reflect the control of the thickness and enlargement of the thermal effect.Article Citation - WoS: 11Citation - Scopus: 17Software Measurement Activities in Small and Medium Enterprises: an Empirical Assessment(Budapest Tech, 2011) Pusatli, O. Tolga; Pusatlı, Özgür Tolga; Misra, Sanjay; Tolga Pusatli, O.; Yönetim Bilişim SistemleriAn empirical study for evaluating the proper implementation of measurement/metric programs in software companies in one area of Turkey is presented. The research questions are discussed and validated with the help of senior software managers (more than 15 years' experience) and then used for interviewing a variety of medium and small scale software companies in Ankara. Observations show that there is a common reluctance/lack of interest in utilizing measurements/metrics despite the fact that they are well known in the industry. A side product of this research is that internationally recognized standards such as ISO and CMMI are pursued if they are a part of project/job requirements; without these requirements, introducing those standards to the companies remains as a long-term target to increase quality.Article Beyond Compliance: Multi-Dimensional Text Mining Analysis of Corporate Sustainability Reporting(Bucharest University of Economic Studies Publishing House, 2025) Şener, İ.; Balcıoğlu, Y.S.; Karapolatgil, A.A.This study investigates how organisations respond to Corporate Sustainability Reporting Directive (CSRD) requirements through systematic analysis of corporate communications and sustainability reports. We employ multi-dimensional text mining analysis of 500 companies across 12 industries, using lexical analysis, sentiment analysis, and network analysis of sustainability reports (2022-2024) and corporate communications (1.200 documents) from TIME’s Most Sustainable Companies ranking. Three distinct organisational response patterns emerge: compliance-oriented positioning (35%), transformation-oriented positioning (42%), and value-creation positioning (23%). Service-oriented sectors demonstrate positive sentiment (+0.67) toward CSRD implementation, while resource intensive industries show negative sentiment (-0.14). The cross-country analysis reveals distinct national approaches reflecting institutional contexts. This study contributes the first large-scale text mining analysis of CSRD implementation responses, providing empirical evidence of heterogeneous organisational approaches to sustainability reporting beyond simple compliance frameworks. The multi-dimensional methodology enables systematic comparison across industries and countries, revealing sector-specific implementation patterns previously unidentified in sustainability reporting literature. Findings inform policymakers about industry-specific implementation challenges and demonstrate that regulatory framing significantly influences organisational strategic positioning toward sustainability reporting. © 2025 The Author(s). This is an Open Access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited. © 2025 The Author(s).Article Citation - Scopus: 2Damage Detection in Aircraft Engine Borescope Inspection Using Deep Learning(Springer Science and Business Media Deutschland GmbH, 2025) Uzun, I.; Tolun, M.R.; Sari, F.; Alpaslan, F.N.Aircraft engine inspection is a key pillar of aviation safety as it helps to maintain adequate performance standards to ensure engine airworthiness. In addition, it is also vital for asset value retention. Borescope inspection is currently the most widely used visual inspection method for aircraft engines. However, borescope inspection is a time-consuming, subjective, and complex process that heavily depends on the experience and attention level of the inspector. Moreover, the cost savings of airlines and the maintenance, repair, and overhaul (MRO) centers expose pressure and workload on inspectors. These factors make an automated system to support damage detection during borescope inspection necessary in order to mitigate potential risks. In this paper, we propose a deep learning-based automated damage detection framework that employs aircraft engine borescope inspection images. Faster R-CNN-based deep learning model with Inception v2 feature extractor is utilized for the present architecture. Due to the limited number of images, data augmentation and other overfitting methods are also employed. The framework supports crack, burn, nick, and dent damage types across all modules of turbofan engines. It is trained and validated with moderate to complex borescope images obtained from the field. The framework achieves 92.64% accuracy for crack, 92.05% for nick or dent, and 81.14% for burn damage classes, with an overall 88.61% average accuracy. © The Author(s) 2025.Article Citation - WoS: 1Citation - Scopus: 1Evaluating Electricity Demand Elasticity From a Social Perspective: Implications for Sustainable Development and Urban Resilience(IEEE-Inst Electrical Electronics Engineers inc, 2025) Nanehkaran, Yaser A.; Tang, Shixi; Jahani, Amir Bairami Akhi; Niromandfam, Amir; Pusatli, Tolga; Bairami Akhi Jahani, AmirThe central focus of this study revolves around constructing a comprehensive load model to estimate the elasticity of electricity demand predicated on customers' risk-averse tendencies. This model serves as the foundation for designing a proficient demand response program. Moreover, a welfare function is employed to ascertain the optimal incentives to motivatecustomers to curtail their electricity consumption. Given Iran's recent socioeconomic challenges marked by a high inflation rate and inadequate investment in power plants, data from the Iranian power system is employed to validate the efficacy of the proposed model in the numerical analysis. The findings reveal that customers exhibiting higher levels of risk aversion tend to derive greater satisfaction from consuming electricity and consequently necessitate more substantial incentives to prompt a reduction in their demand. Additionally, the results highlight that variations in electricity prices can counterbalance the impact of income increases on consumption patterns.Article Citation - Scopus: 1Timbre of the Place: a Deleuzoguattarian Inquiry To Assemble Music and Place(Sage Publications inc, 2025) Golgelioglu, Can; Ataov, AnliThis study explores the potentials of affects and music in terms of Deleuzoguattarian assemblage thinking. It adopts music as an emancipatory medium to comprehend the post-representative emergences and the togetherness of affective relationalities in place experiences. The study presents an experiential inquiry of composing the musical pieces of two contrasting places and deciphering the spatial stimuli of two contrasting musical pieces. The findings suggest that music, with its rich relational and affective qualities, can significantly contribute to the understanding of places as it transcends the traditional representational mediums, allowing for a deeper appreciation of urban environments' complexities and self-organizing nature.Article Citation - WoS: 1Citation - Scopus: 1Vertical Self-Assembly of Gold Nanoworms for Sensitive Surface-Enhanced Raman Spectroscopy-Based Trace Detection(Amer Chemical Soc, 2025) Khan, Ghazanfar Ali; Demir, Ahmet Kemal; Demirtas, Ozge; Tasgin, Dilek Isik; Bek, Alpan; Bhatti, Arshad Saleem; Ahmed, Waqqar; Isik Tasgin, DilekThe assembly of anisotropic nanoparticles into closely packed structures results in unique functionalities. Herein, we report a 3D multilayer vertical assembly of worm-shaped Au nanoparticles using a carefully regulated evaporation-induced deposition method. With the evaporation of the nanoworm (NW) suspension, the concentration of NWs in the suspension gradually increases, which generates a balance between electrostatic interactions and entropically driven attraction to produce multilayer vertical assemblies. These assemblies exhibit enhanced surface-enhanced Raman scattering (SERS) signals due to the presence of a high concentration of hotspots. Moreover, in contrast to nanorods, the bent morphology of NWs creates pores in the vertical assembly, enabling the analyte molecule to penetrate the assembly and access hotspots. Picomolar to micromolar concentrations of rhodamine 6G (R6G) were detected with the NW assembly-based SERS substrate with excellent linearity and uniformity of the signal with a spot-to-spot relative standard deviation (RSD) of only 8.9%. The SERS substrates were also employed for trace detection of ammonium nitrate, which is a well-known constituent of homemade explosives. Our method of producing multilayer vertical assemblies of NWs is simple, highly sensitive, stable, and reproducible for making effective SERS sensors for the quantitative detection of analytes.