Scopus İndeksli Yayınlar Koleksiyonu
Permanent URI for this collectionhttps://hdl.handle.net/20.500.12416/8651
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Article Investigations on the Effect of Secondary Treatments on Ti48Al2Cr2Nb Alloy Manufactured by Electron Beam Powder Bed Fusion Method(Elsevier Sci Ltd, 2025) Bilgin, Guney Mert; Ozer, Seren; Davut, Kemal; Esen, Ziya; Dericioglu, Arcan F.As-built Ti48Al2Cr2Nb alloy samples produced by electron beam powder bed fusion (PBF-EB) exhibited notable brittleness. The low ductility was attributed to coarse gamma bands aligned perpendicular to the building and tensile direction. Additionally, variations in aluminum content and hardness between the coarse colonies and fine gamma/alpha(2) lamellae contribute to this phenomenon. Electron backscattered diffraction (EBSD) studies revealed a higher amount of dislocation density and inherent strain after PBF-EB manufacturing. Hence, usage of Ti48Al2Cr2Nb alloy in the as-built condition in aviation applications with high loads and demanding environments is not found to be viable. To eliminate these negative aspects and make PBF-EB produced Ti48Al2Cr2Nb alloy available for demanding applications, two distinct post-processing heat treatments; namely, hot isostatic pressing (HIP) and annealing heat treatment (HT) were employed at 1200 degrees C. A comprehensive characterization covering microstructure analysis, EBSD, fracture surface examination, as well as room and high-temperature tensile tests allowed determination of the effect of post-processes. HIPing altered the banded structure observed in the as-built samples by increasing the amount of alpha(2) phase and grain size. On the other hand, HT made the banded structure more pronounced without significantly increasing the amount of alpha(2) phase. HT also strengthened the <001> texture, while HIPing introduced randomization of grains. On the other hand, complete recrystallization is achieved as a result of HT at 1200 degrees C for 2 h, whereas HIPing at the same temperature for 2 h induced only 80.5 % recrystallization. In both post-processes, dislocation density and inherent strain were reduced. Room temperature and high-temperature tensile tests demonstrated that both HIPing and HT eliminated the extreme brittleness of the as-built samples.Article Citation - WoS: 2Citation - Scopus: 2Evaluation of the Turkish Soundscape Circumplex Model, and the Effects of Sound Source Dominance, Sequence, and Gender on the Perceived Affective Quality(Elsevier Sci Ltd, 2024) Yorukoglu, Papatya Nur Dokmeci; Bayrak, Ozlem Turker; Coban, Nilguen Akbulut; Osma, Ugur Beyza Ercakmak; Nur Dökmeci Yörükoğlu, Papatya; Beyza Erçakmak Osma, Uğur; Türker Bayrak, Özlem; Akbulut Çoban, NilgünThe International Standard Organization (ISO) standards series on soundscape for the identification, data collection and data analysis present a general framework for the soundscape studies that are conducted globally. Perceived Affective Qualities (PAQs) including 8 soundscape perceptual attributes in ISO/TS 12913-2:2018 and ISO/TS 12913-3:2019 are published in English language. Therefore, the 'Soundscape Attributes Translation Project' focuses on the reliable standardized translations of the PAQs in other languages. In the previously published Turkish translation and validation study, the PAQs were presented as; 'hareketli' (eventful), 'coskulu' (vibrant), 'keyifli' (pleasant), 'sakin' (calm), 'dura.gan' (uneventful), 'tekduze' (monotonous), 'rahatsiz edici' (annoying), and 'karmas ik' (chaotic). Within the scope of this follow-up study, firstly, sound sources in each audio stimulus are identified according to their dominance to explore their relation with the Soundscape Circumplex Model (SCM) quadrants and found that the human dominant audio stimuli are evaluated as 'vibrant' in SCM. Other noise dominating audio stimuli are categorized as 'monotonous' while traffic combined with other noise audio stimuli are evaluated as 'chaotic'. When the audio stimuli evaluated as 'calm' are investigated, they are either purely dominated by natural sounds or mixture of each category dominated by natural sounds. Secondly, a comparison between the Turkish and the English participants' evaluation of audio stimuli according to the SCM is done and found that they are similar except two audio stimuli. Furthermore, the effect of audio stimulus sequence and gender on 8 PAQs are statistically analysed through Kruskall-Wallis and Mann-Whitney tests; respectively and found that both are significant. The sequences shifting from 'chaotic' to 'calm' or vice versa frequently are seen to be evaluated with higher scores whereas more homogenous ones in sequence, i.e. audio stimuli having the same dominating sound source are sequenced together mostly are graded with lower scores of 8 PAQs except 'chaotic' compared to drastic changes in the sound source and found that men grade 'cos kulu' (vibrant), 'dura.gan' (uneventful), 'tekduze' (monotonous), 'rahatsiz edici' (annoying) and 'karmasik' (chaotic) more than women by 5, 11, 24, 8 and 10 points, respectively according to the median values. Finally, conformance to the SCM is evaluated by the principal component analysis (PCA) and found that it can be reduced to two dimensions named as "pleasantness" and "eventfulness" in expected order but the main PAQs pleasant-annoying and eventful-uneventful are not aligned indicating the lack of achieving the ideal circumplexity. It is believed that the results of this study could contribute to both national and international future soundscape research with a focus on listening tests applying PAQs.Article Citation - WoS: 1Citation - Scopus: 1Optical Wireless Sensor Networks in Underwater Turbulence Using Multimode Beams(Elsevier Sci Ltd, 2025) Baykal, YahyaOptical wireless sensor networks (OWSN) that employ multimode optical beams operating in underwater turbulence are investigated. For this purpose, off-axis average intensity at the destination point (receiver) is formulated in underwater turbulence when the incidences at the sensors are multimode optical beams. Based on the trends of the appropriately determined off-axis received average intensities of various multimode beams, identification of the sensor can be made. The proposed procedure is also applied as special cases, to optical wireless sensor networks that employ single higher mode beams.Correction The Hesitant Pythagorean Fuzzy Electre Iii: an Adaptable Recycling Method for Plastic Materials (Vol 291, 125281, 2021)(Elsevier Sci Ltd, 2024) Geetha, Selvaraj; Narayanamoorthy, Samayan; Kureethara, Joseph Varghese; Baleanu, Dumitru; Kang, DaekookArticle Citation - WoS: 7Citation - Scopus: 8Adaptive Modeling of Landslide Susceptibility Using Analytical Hierarchy Process and Multi-Objective Decision Optimization(Elsevier Sci Ltd, 2025) Mao, Yimin; Zhu, Licai; Chen, Junde; Nanehkaran, Yaser A.This study develops a detailed landslide susceptibility map for Kermanshah province, Iran, by analyzing field surveys, historical data, and remote sensing. Fifteen key factors-such as geomorphology, geology, climate, seismicity, and human activities-were identified and ranked using Analytical Hierarchy Process (AHP) and Multi-Objective Decision Optimization (MODO) within a GIS framework. The analysis classifies landslide risk into five categories: very high (18.4%), high (33.98%), moderate (24.19%), low (14.36%), and very low (9.07%). Pixel rate assessment confirmed the map's accuracy, showing that eastern and northeastern regions are particularly prone to landslides, with a substantial portion of the province at moderate to high risk. The study recommends using this map to guide targeted risk mitigation and land-use planning efforts to reduce landslide impacts on vulnerable areas. (c) 2024 COSPAR. Published by Elsevier B.V. All rights are reserved, including those for text and data mining, AI training, and similar technologies.Article Citation - WoS: 5Citation - Scopus: 5Examining Disparities in Energy Poverty and Indoor Environmental Quality Satisfaction Among Canadian Households(Elsevier Sci Ltd, 2024) Nojedehi, Pedram; Gunay, Burak; O'Brien, William; Papineau, Maya; Azar, Elie; Schweiker, Marcel; Saglam, Nese Ganic; Ganiç Saglam, NeseThis study explores the relationship between income, dwelling quality, and indoor environmental quality (IEQ) perceptions. We conducted a survey of approximately 1100 Canadian residents from a variety of socioeconomic groups capturing a representative sample of Canadian society. It employs new thresholds to align the subjective perceptions of energy poverty with objective measures. Statistical analyses reveal notable differences in IEQ perceptions among income groups. While high-income respondents consistently express higher satisfaction levels across multiple IEQ domains than middle-income ones, the latter report higher satisfaction levels than those with lower incomes. Wealthier households typically have more rooms, with all income groups reporting a median of three bedrooms. Lower-income respondents tend to spend a larger proportion of their income on energy bills per capita, despite consuming less energy per capita. Around 41% of lower-income respondents report facing challenges in paying utility bills, compared to 24% and 16% in middle- and upper-income groups, respectively. We present energy poverty thresholds that are customized based on survey responses from the different income groups, informing policymakers to consider downward revisions of thresholds to address the subjective aspect of energy poverty better. The unequal IEQ and energy poverty perceptions we document across income groups highlight the need for targeted interventions to improve welfare among vulnerable households.Article Citation - WoS: 3Citation - Scopus: 3Characterization of Micro-Wire Electrical Discharge Machining Surface Texture by Empirical Mode Decomposition(Elsevier Sci Ltd, 2025) Morovatdel, Mehrdad; Osguei, Amin Taraghi; Ustunel, Yasar Can; Oliaei, Samad Nadimi Bavil; Nadimi Bavil Oliaei, Samad; Can Üstünel, Yaşar; Taraghi Osguei, AminSurface roughness is a critical factor for the operational efficacy and lifespan of the manufactured components, often serving as a key metric for evaluating manufacturing processes and determining acceptance of a component. Traditional surface roughness measurements are highly sensitive to the fixed standard cut-off length, influencing the scale at which surface texture features are analyzed. Thus, developing techniques with more reliable filtering of surface features is essential for accurate surface metrology. This research proposes a novel method that combines Empirical Mode Decomposition (EMD) and Fast Fourier Transform (FFT) for surface roughness characterization. We applied our method to Nitinol shape memory alloy (equal atomic proportions of nickel and titanium) surfaces processed using micro-Wire Electrical Discharge Machining (mu-WEDM). Our results demonstrate that the EMD-FFT method significantly outperforms traditional filtering, especially for surfaces without distinct patterns like mu-WEDM. This improvement is particularly valuable for materials like Nitinol, which is widely used in critical applications where precise surface roughness control is essential. By accurately assessing the effects of mu-WEDM parameters on surface roughness, the proposed method reveals that for a constant pulse on time and a constant discharge current, the variation of pulse off time is more important than servo voltage. Thus, this method can contribute to optimizing manufacturing processes and producing higherquality components with improved performance and durability.Article Citation - WoS: 6Citation - Scopus: 7The Hydraulic Investigation of Harmonic Plan Weirs(Elsevier Sci Ltd, 2024) Yildiz, Ali; Marti, Ali Ihsan; Gogus, MustafaExisting dams and reservoirs need to be revised to meet safety standards. For the existing reservoirs where flood control is important and the maximum water level is limited, the best method to increase reservoir capacity is to build a labyrinth weir on the dam. In labyrinth weirs, the collision of two nappe flows produces nappe inter-ference, and this reduces the weir performance. In this study, the semi-circle weirs are placed in an open channel harmonically to increase the efficiency of the labyrinth weirs to make the areas more efficient and increase the flow capacity because of the nappe interference and to ensure the flow moving perpendicular to the weir as possible. In the experimental study of the asymmetrically placed circular weirs, 3 different weir heights (P = 20 cm, 30 cm and 40 cm) and 3 different labyrinth cycle numbers (N = 2, N = 3 and N = 4) were used. As a result of the experiments, although there was a 13 % decrease in the discharge coefficients (Cd) compared to the linear weirs, it provided a 57 % increase in the net crest length (Lnet). Discharge coefficient (Cd) is decreased 3.4 %, as the number of cycles (N) increases. As the weir height (P) decreases, Cd increases 7.5 % due to the vacuum effect.Correction A Comparative Study of Silicon Nitride and Sialon Ceramics Against E. Coli (Vol 47, Pg 1837, 2021)(Elsevier Sci Ltd, 2021) Akin, Seniz R. Kushan; Garcia, Caterina Bartomeu; Webster, Thomas J.; Bartomeu Garcia, Caterina; Kushan Akin, Seniz R.Article Citation - WoS: 9Citation - Scopus: 8Effects of Reverberation Time and Sound Source Composition on Sense of Place Constructs(Elsevier Sci Ltd, 2022) Al-bayyar, Zinah; Kitapci, KivancThis study investigates the influence of reverberation time and sound source composition on the sense of place. The experiments were conducted in the private lecturer offices located in the Faculty of Architecture, cankaya University. The sense of place of 15 participants was tested in the original offices of each participant and eight additional acoustic auralisations, in which reverberation times and sound source compositions were modified. The analysis of the results revealed that there is a direct influence of reverberation time and sound source composition on the sense of place. It was observed that longer reverberation times partially enhanced the sense of place. Additionally, the sound source composition influenced the relation towards the place, and certain sound signals diminished the sense of place in the private offices. Furthermore, this study used a psychophysical scaling method (Absolute Magnitude Estimation scale [AME]) which indicated its validity and importance in investigating the effect of physical stimuli on the sense of place. The AME revealed the sense of place by directing the influence towards the place construct indicators rather than investigating the general relation towards the place. It was concluded that reverberation time and sound source compositions could enhance and/or diminish sense of place; hence, RT and sound source compositions can affect interpretation of and behavior towards a given place. (C) 2021 Elsevier Ltd. All rights reserved.