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Article Citation - WoS: 7Citation - Scopus: 10Combined Use of Ultrasonic-Assisted Drilling and Minimum Quantity Lubrication for Drilling of Niti Shape Memory Alloy(Taylor & Francis inc, 2023) Namlu, Ramazan Hakki; Lotfi, Bahram; Kilic, S. Engin; Yilmaz, Okan Deniz; Akar, SametThe drilling of shape-memory alloys based on nickel-titanium (Nitinol) is challenging due to their unique properties, such as high strength, high hardness and strong work hardening, which results in excessive tool wear and damage to the material. In this study, an attempt has been made to characterize the drillability of Nitinol by investigating the process/cooling interaction. Four different combinations of process/cooling have been studied as conventional drilling with flood cooling (CD-Wet) and with minimum quantity lubrication (CD-MQL), ultrasonic-assisted drilling with flood cooling (UAD-Wet) and with MQL (UAD-MQL). The drill bit wear, drilling forces, chip morphology and drilled hole quality are used as the performance measures. The results show that UAD conditions result in lower feed forces than CD conditions, with a 31.2% reduction in wet and a 15.3% reduction in MQL on average. The lowest feed forces are observed in UAD-Wet conditions due to better coolant penetration in the cutting zone. The UAD-Wet yielded the lowest tool wear, while CD-MQL exhibited the most severe. UAD demonstrated a & SIM;50% lower tool wear in the wet condition than CD and a 38.7% in the MQL condition. UAD is shown to outperform the CD process in terms of drilled-hole accuracy.Article Citation - WoS: 4Citation - Scopus: 5Space Efficiency in Tall Hotel Towers(Mdpi, 2024) Aslantamer, Ozlem Nur; Ilgin, Huseyin EmreMaximizing spatial utilization within tall buildings stands as a paramount planning consideration for ensuring project feasibility, particularly accentuated ins the context of hotel constructions. To date, no comprehensive study has addressed this issue while considering crucial architectural and structural planning factors. This article fills this gap by using a case study method based on data from 31 contemporary tall hotel towers. The findings revealed several key points: (i) central core typology was mostly utilized; (ii) prismatic buildings were the most prevalent forms; (iii) shear-walled frame systems were predominantly employed; (iv) concrete was the preferred choice for hotel construction; (v) the average space efficiency and the ratio of core area to gross floor area (GFA) averaged 81.2% and 16%, respectively; (vi) the range changed from a minimum of 70% to 4% to a maximum of 94% to 28%; and (vii) space efficiency showed an inverse relationship with the height of the building. It is anticipated that this paper will assist architects and structural engineers as well as builders involved in the planning of hotel developments.Article Citation - WoS: 3Citation - Scopus: 3Expectancy From, and Acceptance of Augmented Reality in Dental Education Programs: a Structural Equation Model(Wiley, 2024) Toker, Sacip; Akay, Canan; Basmaci, Fulya; Kilicarslan, Mehmet Ali; Mumcu, Emre; Cagiltay, Nergiz ErcilObjectiveDental schools need hands-on training and feedback. Augmented reality (AR) and virtual reality (VR) technologies enable remote work and training. Education programs only partially integrated these technologies. For better technology integration, infrastructure readiness, prior-knowledge readiness, expectations, and learner attitudes toward AR and VR technologies must be understood together. Thus, this study creates a structural equation model to understand how these factors affect dental students' technology use.MethodsA correlational survey was done. Four questionnaires were sent to 755 dental students from three schools. These participants were convenience-sampled. Surveys were developed using validity tests like explanatory and confirmatory factor analyses, Cronbach's alpha, and composite reliability. Ten primary research hypotheses are tested with path analysis.ResultsA total of 81.22% responded to the survey (755 out of 930). Positive AR attitude, expectancy, and acceptance were endogenous variables. Positive attitudes toward AR were significantly influenced by two exogenous variables: infrastructure readiness (B = 0.359, beta = 0.386, L = 0.305, U = 0.457, p = 0.002) and prior-knowledge readiness (B = -0.056, beta = 0.306, L = 0.305, U = 0.457, p = 0.002). Expectancy from AR was affected by infrastructure, prior knowledge, and positive and negative AR attitudes. Infrastructure, prior-knowledge readiness, and positive attitude toward AR had positive effects on expectancy from AR (B = 0.201, beta = 0.204, L = 0.140, U = 0.267, p = 0.002). Negative attitude had a negative impact (B = -0.056, beta = -0.054, L = 0.091, U = 0.182, p = 0.002). Another exogenous variable was AR acceptance, which was affected by infrastructure, prior-knowledge preparation, positive attitudes, and expectancy. Significant differences were found in infrastructure, prior-knowledge readiness, positive attitude toward AR, and expectancy from AR (B = 0.041, beta = 0.046, L = 0.026, U = 0.086, p = 0.054).ConclusionInfrastructure and prior-knowledge readiness for AR significantly affect positive AR attitudes. Together, these three criteria boost AR's potential. Infrastructure readiness, prior-knowledge readiness, positive attitudes toward AR, and AR expectations all increase AR adoption. The study provides insights that can help instructional system designers, developers, dental education institutions, and program developers better integrate these technologies into dental education programs. Integration can improve dental students' hands-on experience and program performance by providing training options anywhere and anytime.Article Citation - WoS: 7Citation - Scopus: 9The Mean Number of Failed Components in Discrete Time Consecutive K-Out F System and Its Application To Parameter Estimation and Optimal Age-Based Preventive Replacement(Elsevier Sci Ltd, 2025) Eryilmaz, Serkan; Kan, CihangirIt is important in many respects to have information about the number of failed components in the system when or before a system fails. This paper investigates the mean number of failed components at or before the failure time of the linear consecutive k-out-of-n:F system which is a useful structure to model various engineering systems such as transportation and transmission systems. In particular, closed form expressions for the mean number of failed components within the system that have discretely distributed components lifetimes are obtained. The results are used to estimate the unknown parameter of the components' lifetime distribution and to find the optimal replacement cycle that minimizes the expected cost per unit of time under a certain age-based replacement policy.Article Education With Experience: Assessment of a Co-Op Model in Undergraduate Engineering Programs in Computing(Ieee Computer Soc, 2023) Nazlioglu, Selma; Turhan, Cigdem; Yazici, AliA major concern among graduates of computing departments is the discrepancy between the expectations of software companies and the competencies provided by the academic departments. This ongoing problem makes co-op education inevitable, as it combines industrial experience with traditional education.Article Citation - WoS: 15Citation - Scopus: 17An Experimental Study on Ultrasonic-Assisted Drilling of Inconel 718 Under Different Cooling/Lubrication Conditions(Springer London Ltd, 2024) Erturun, Omer Faruk; Tekaut, Hasan; Cicek, Adem; Ucak, Necati; Namlu, Ramazan Hakki; Lotfi, Bahram; Kilic, S. EnginUltrasonic-assisted drilling (UAD) is one of the efficient and innovative methods to improve the drillability of difficult-to-cut materials. In the present study, the UAD of Inconel 718 was investigated under different cooling and/or lubrication conditions. The drilling tests were carried out at a constant cutting speed (15 m/min) and a feed (0.045 mm/rev) using uncoated and TiAlN-coated solid carbide drills under dry, conventional cutting fluid (CCF), and minimum quantity lubrication (MQL) conditions. The applicability of UAD to drilling Inconel 718 was evaluated in terms of thrust force, surface roughness, roundness error, burr formation, subsurface microstructure and microhardness, tool wear, and chip morphology. The test results showed that, when compared to conventional drilling (CD), UAD reduced the thrust force and improved the hole quality, tool life, and surface integrity under all conditions. Good surface finish, lower roundness error, and minimum burr heights were achieved under CCF conditions. MQL drilling provided lower thrust forces, better tool performance, and good subsurface quality characteristics. In addition, the simultaneous application of CCF-UAD and MQD-UAD showed significantly better performance, especially when using the coated tool.Article Citation - WoS: 5Citation - Scopus: 5Identification of Shallow Trap Centers in Inse Single Crystals and Investigation of Their Distribution: a Thermally Stimulated Current Spectroscopy(Elsevier, 2024) Isik, M.; Gasanly, N. M.Identification of trap centers in semiconductors takes great importance for improving the performance of electronic and optoelectronic devices. In the present study, we employed the thermally stimulated current (TSC) method within a temperature range of 10-280 K to explore trap centers in InSe crystal-a material with promising applications in next-generation devices. Our findings revealed the existence of two distinct hole trap centers within the InSe crystal lattice located at 0.06 and 0.14 eV. Through the leveraging the T-stop method, we offered trap distribution parameters of revealed centers. The results obtained from the experimental methodology employed to investigate the distribution of trap centers indicated that one of the peaks extended between 0.06 and 0.13 eV, while the other spanned from 0.14 to 0.31 eV. Notably, our research uncovers a remarkable variation in trap density, spanning one order of magnitude, for every 10 and 88 meV of energy variation. The results of our research present the characteristics of shallow trap centers in InSe, providing important information for the design and optimization of InSe-based optoelectronic devices.Article Citation - WoS: 3Citation - Scopus: 3The Role of Honor Concerns in Disclosing (vs. Hiding) COVID-19 Diagnosis: Insights from Turkiye(Springer/plenum Publishers, 2023) Ceylan-Batur, Suzan; Dogulu, Canay; Akbas, Gulcin; Yet, Barbaros; Uskul, Ayse K. K.Members of honor cultures value engaging in moral behaviors and managing their social image to maintain their honor. These two goals reflect reputation and integrity concerns, which also have bearing on gender roles. In the current study, we examined a) evaluations of women and men described as diagnosed with COVID-19 and as either hiding or disclosing their diagnosis, b) the moderating role of honor concerns (reputation and integrity) and the gender of the infected person in these evaluations, and c) the relationship between honor concerns and individuals' own disclosure preferences among participants living in Turkiye, a country that exemplifies an honor culture. Findings revealed that participants with stronger reputation concerns evaluated a woman's hiding behavior more favorably than that of a man's. Moreover, higher integrity concerns were associated with lower levels of participants' own preference to hide a diagnosis for both men and women, whereas reputation concerns were positively associated with a preference for hiding a diagnosis among men only. Furthermore, a content analysis of participants' open-ended explanations of their views on women's and men's motivation to hide a diagnosis revealed further evidence for the gendered nature of reputation concerns. Our findings point to the importance of prioritizing integrity concerns (and downplaying reputation concerns) in public health campaigns in honor cultures.Article Red Vienna: Ideology, Architecture and Art in the Reumannhof Municipal Social Housing(Middle East Technical Univ, 2024) Pfeiffer Tas, Sule; Temel, Rabia; Taş, Şule PFEIFFERThis study focuses on the Reumannh of Social Housing Complex, which was designed by Hubert Gessner (1871-1943) and constructed between 1924 and 1926 in Vienna. It was one of the largest buildings as part of the Municipal Social Housing Program for workers implemented under the leadership of Jakob Reumann, who was the mayor of Vienna between 1919 and 1923. According to the social democratic ideology in Vienna, known as the Red Vienna period (1919-1934) of the city administration, this program aimed to meet the housing needs of the working class and to provide them with better living conditions. Due to the increase in worker migration to the city after the Industrial Revolution and upon the demolition of the city during World War I, a housing crisis emerged in Vienna and unfavorable living conditions - such as one-room apartments and rental beds even for a few hours - became a necessity. The paper attempts to probe into the nature of the connection between the Reumannh of Complex architecture and the Red Vienna ideology in light of the social democratic perspective of the working class. In order to do so, the entire structure - known as "the palace of the working class" - is analyzed in detail while pointing to similar social housing complexes, such as Metzleinstalerh of on the Margareteng & uuml;rtel known as "Proletarian's Boulevard" and nearby. Additionally, the standardization criteria, as envisioned within the context of the social housing program, are examined to find out any traces of their presence (or improvements/modifications upon them) in the Reumannh of Complex. In the context of the political and socio-economic conditions of that era, a comparative analysis of the architectural elements and landscape architecture is conducted, such as courtyards and Haydn park on the front in the latter case. Original archival documents, photographs, and drawings of the complex were collected and during the course of the field research, photographs were taken. A housing typology and drawings were made in accordance with the general floor plan of the building, drawn by Gessner himself to determine the details related to the features of the houses - such as kitchen, living room+kitchen, and the number and function of the rooms - in order to determine the reflection of the living comfort promised by the social democratic ideology. As a result, three main plan types were identified based on the spaces contained within the houses, and subgroups were created according to balconies, terraces, or bay windows, all of which provided daylight and fresh air. In conclusion, the research establishes that the Reumannhof Complex houses, common facilities as terraces, infant school, laundry rooms, etc. all implemented standards that were mostly aligned with those related to welfare and in line with the principles of social democratic ideology. Lastly, it is revealed that architectural and artistic elements, such as wrought iron, ceramic panels illustrating craftsmen and different professions, motifs, and sculptures, not only reflect the social democratic ideology and motto, but also create new living environments by integrating architectural design with green spaces for the working class. As witness to this assertion, it is useful to notice that the complex still serves the function of economic housing for the working class and remains important as a symbol of social democratic ideology.Article The Impact of Quaternization Degree in Polyepichlorohydrin-Based Anion Exchange Membranes on Salinity Gradient Energy Generation by Reverse Electrodialysis(Elsevier, 2025) Cihanoglu, Aydin; Guler, Enver; Kabay, NalanAnion exchange membranes with tailored fixed-charge densities can improve monovalent ion selectivity and performance in reverse electrodialysis for salinity gradient power generation. In this study, poly(epichlorohydrin) was blended with polyacrylonitrile and quaternized with 1,4-diazabicyclo[2.2.2]octane at three different molar ratios to produce AEMs with systematically varied quaternization degrees via a one-step amination/ crosslinking procedure. The resulting membranes were characterized for their physicochemical, electrochemical, and RED performance using ATR-FTIR, XPS, SEM, AFM, water uptake, swelling degree, contact angle, surface zeta potential, ion exchange capacity, fixed charge density, and electrical resistance. Higher quaternization increased the IEC, reduced resistance, and shifted surface charge, leading to improved stack power output in model NaCl solutions. In the presence of Na2SO4, power loss was reduced for more highly quaternized membranes, indicating enhanced exclusion of divalent anions (SO42-) and reduced uphill transport. Fouling tests with humic acid/fulvic acid mixtures showed greater stability for quaternized membranes compared to a commercial benchmark. Moreover, stability tests conducted on fouled membranes revealed that the tailor-made membrane exhibits superior durability and lower fouling-induced power loss than commercial Fujifilm Type II AEMs. Overall, these results demonstrate that tuning the degree of quaternization is an effective strategy to balance conductivity and ion selectivity in AEMs for RED applications.