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Citation - WoS: 8
Citation - Scopus: 10
Computing Reliability Indices of a Wind Power System Via Markov Chain Modelling of Wind Speed
(Sage Publications Ltd, 2024) Eryilmaz, Serkan; Bulanik, Irem; Devrim, Yilser
Statistical modelling of wind speed is of great importance in the evaluation of wind farm performance and power production. Various models have been proposed in the literature depending on the corresponding time scale. For hourly observed wind speed data, the dependence among successive wind speed values is inevitable. Such a dependence has been well modelled by Markov chains. In this paper, the use of Markov chains for modelling wind speed data is discussed in the context of the previously proposed likelihood ratio test. The main steps for Markov chain based modelling methodology of wind speed are presented and the limiting distribution of the Markov chain is utilized to compute wind speed probabilities. The computational formulas for reliability indices of a wind farm consisting of a specified number of wind turbines are presented through the limiting distribution of a Markov chain. A case study that is based on real data set is also presented.
Citation - WoS: 10
Citation - Scopus: 11
Analysis of Space Efficiency in High-Rise Timber Residential Towers
(Mdpi, 2024) Ilgin, Hueseyin Emre; Aslantamer, Ozlem Nur
High-rise timber residential towers (>= eight-stories) represent a burgeoning and auspicious sector, predominantly due to their capability to provide significant ecological and financial advantages throughout their lifecycle. Like numerous other building types, spatial optimization in high-rise timber residential structures stands as a pivotal design factor essential for project viability. Presently, there exists no comprehensive investigation on space efficiency in such towers. This study analyzed data from 51 case studies to enhance understanding of the design considerations influencing space efficiency in high-rise timber residential towers. Key findings included (1) the average space efficiency within the examined cases was recorded at 83%, exhibiting variances ranging from 70% to 93% across different cases, (2) the average percentage of core area to gross floor area (GFA) was calculated at 10%, demonstrating fluctuations within the range of 4% to 21% across diverse scenarios, and (3) no notable distinction was observed in the effect of various core planning strategies on spatial efficiency when properly designed, and similar conclusions were drawn regarding building forms and structural materials. This research will aid in formulating design guidelines tailored for various stakeholders such as architectural designers involved in high-rise residential timber building developments.
Citation - WoS: 3
Citation - Scopus: 3
Incidence of Medical Device-Related Pressure Injuries and Identification of Risk Factors in the Neonatal Unit
(Elsevier Sci Ltd, 2024) Yarkiner, Zalihe; Bahar, Arzu; Sonmez, Munevver; Kapan, Emine; Sahin, Simge; Kostekci, Ezgi; Erdeve, Omer
Aim: This study was conducted to investigate the incidence of medical device-related pressure injuries (MDRPIs) and the risk factors influencing their occurrence in the neonatal intensive care unit (NICU). Method: This study is a prospective, descriptive study. The research was conducted with 116 newborns between June 1, 2022, and June 1, 2023. Newborns who stayed in the neonatal intensive care unit for at least 24 h were observed daily for medical device-related pressure injuries under and around each medical device throughout their stay in the intensive care unit. The "Case Report Form," "MDRPIs Monitoring Form," "Braden Q scale for children," National Pressure Injury Advisory Panel (NPIAP) Pressure Grading, and Glasgow Coma Scale were used in the research. Results: The incidence of medical device-related pressure injuries is 35.3 % (41/116). It was found that 38.1 % (16/42) of medical device-related pressure injuries developed due to Near-Infrared Spectroscopy (NIRS) probes, and 33.5 % (14/42) developed due to medical devices related to the respiratory system. In terms of anatomical location, 38.1 % occurred on the forehead, and 23.8 % on the arm/leg. The difference between birth weight, gestational age, development of MDRPIs in newborns receiving sedation and inotropes was found to be statistically significant. Regression analysis identified gestational age (p = 0.040, OR = 0.795, 95%CI = [0.632-1.000]) as an independent risk factor for the occurrence of medical device-related pressure injuries. Conclusions: The incidence of medical device-related pressure injuries in newborns was relatively high in this study, with gestational age being the most significant risk factor for MDRPIs formation. It is crucial for neonatal intensive care nurses to consider associated risk factors while providing newborn care and implement appropriate preventive measures to reduce the incidence of MDRPIs.
Citation - WoS: 7
Citation - Scopus: 10
Space Efficiency in North American Skyscrapers
(Mdpi, 2024) Ilgin, Huseyin Emre; Aslantamer, Ozlem Nur
Space efficiency in North American skyscrapers is crucial due to financial, societal, and ecological reasons. High land prices in major cities require maximizing every square foot for financial viability. Skyscrapers must accommodate growing populations within limited spaces, reducing urban sprawl and its associated issues. Efficient designs also support environmental sustainability and enhance city aesthetics, while optimizing infrastructure and services. However, no comprehensive study has examined the key architectural and structural features impacting the space efficiency of these towers in North America. This paper fills this gap by analyzing data from 31 case study skyscrapers. Findings indicated that (1) central core was frequently employed in the organization of service core; (2) most common forms were setback, prismatic, and tapered configurations; (3) outriggered frame and shear walled frame systems were mostly used; (4) concrete was the material in most cases; and (5) average space efficiency was 76%, and the percentage of core area to gross floor area (GFA) averaged 21%, from the lowest of 62% and 13% to the highest of 84% and 31%. It is expected that this paper will aid architectural and structural designers, and builders involved in shaping skyscrapers in North America.
Synthesis and Electropolymerization of a Selenophene Based Chemiluminescent Monomer and Its Use in Blood Detection
(Elsevier Sci Ltd, 2025) Balci, Burcu; Cakal, Deniz; Cihaner, Atilla
A new selenophene based trimeric chemiluminescent compound, namely 5,7-di(selenophen-2-yl)-2,3-dihydrothieno[3,4-d]pyridazine-1,4-dione (S2T-Lum), was synthesized in two steps via electron donor-acceptor-donor approach. Its chemiluminescent reaction with hydrogen peroxide was investigated in an alkaline solution in the presence of various catalysts such as different metal ions, hemin and blood samples and the results were compared with its thiophene analogue (T2T-Lum) and luminol. It was found that S2T-Lum was very sensitive to copper(II) and iron(III) ions, and blood samples. Also, it can be easily concluded that S2T-Lum as a new member of luminol type compounds is a potential candidate for the detection of blood findings in forensic science. Furthermore, S2T-Lum has an irreversible oxidation peak at 1.28 V vs Ag/AgCl, which is responsible from its electropolymerization. S2T-Lum was successfully polymerized electrochemically via potentiodynamic electrolysis without cleavage of its chemiluminescent active appendage. To the best of our knowledge, its corresponding polymer PS2T-Lum film is the first member of selenophene based luminol type electroactive polymers.
Citation - WoS: 5
Citation - Scopus: 7
High-Rise Timber Offices: Main Architectural and Structural Design Parameters
(Mdpi, 2024) Ilgin, Hueseyin Emre; Aslantamer, Ozlem Nur
High-rise office structures constructed using timber material (with a minimum of eight stories) signify a burgeoning and favorable sector, mainly owing to their ability to offer substantial environmental and economic advantages across their lifespan. However, it is crucial to recognize that the current corpus of scholarly literature lacks a thorough investigation into vital aspects concerning the architectural and structural planning of these sustainable structures. In an effort to fill this gap and augment the understanding of advancing international tendencies, this paper delved into data originating from 27 high-rise offices on a worldwide scale. The primary findings were: (i) Central core arrangements were the most popular, accounting for 67%, followed by peripheral types at 22%. (ii) Prismatic designs were the most frequently used at 85%, with free forms making up 11%. (iii) Material combinations involving timber and concrete were widely prevalent, making up 70% of composite constructions, which were 74% of the sample group, with pure timber constructions at 26%. (iv) Structural systems predominantly utilized shear walled frame systems, comprising 85% of the total. This article serves as a valuable resource for architectural designers, offering guidance on planning and executing future sustainable developments in the domain of high-rise timber office.
Citation - WoS: 3
Citation - Scopus: 3
Mitigating Student Cynicism for Sustainable Academic Performance: University Identification and Academic Self-Efficacy
(Multidisciplinary Digital Publishing Institute (MDPI), 2025) Tosun, B.; Çetin, F.
This study explores the complex relationships among student cynicism, student–university identification, academic self-efficacy, and academic performance within the context of Turkish higher education. Drawing on social identity and social cognitive theories, student cynicism is examined through four dimensions: academic, policy-related, institutional, and social. Survey data were collected from 630 university students in Ankara, Türkiye, using a cross-sectional design and self-reported measures. The results indicate that institutional cynicism is the strongest negative predictor of student–university identification, while academic cynicism shows a curvilinear (U-shaped) relationship with academic performance, suggesting that extreme cynicism may paradoxically be linked to modest performance rebounds. Contrary to expectations, student–university identification does not significantly predict academic performance, nor does it mediate the relationship between cynicism and performance. However, academic self-efficacy moderates the relationship between identification and performance, amplifying the benefits of identification for students with higher levels of self-efficacy. These findings offer culturally grounded insights into student disengagement and highlight the importance of fostering trust, transparency, and self-efficacy to support student well-being and academic resilience, key elements in advancing Sustainable Development Goals 4 (Quality Education) and 8 (Decent Work and Economic Growth). © 2025 by the authors.
Citation - WoS: 2
Citation - Scopus: 3
Space Efficiency in European High-Rise Timber Buildings
(Mdpi, 2024) Ilgin, Huseyin Emre; Aslantamer, Ozlem Nur
As towering wooden edifices (>= 8 stories) become a rapidly expanding and promising field, they provide substantial environmental and economic advantages throughout their entire lifespans, leading to their increasing popularity, especially in the European context. Similar to various other construction forms, spatial efficiency is a vital design criterion in timber buildings to guarantee the viability of a project. Currently, there is no thorough study on spatial efficiency in these towers in Europe, which is home to the majority of the world's timber towers. This paper examined data from 56 cases to improve comprehension of the planning factors affecting space efficiency in these buildings. The main findings showed that the average space efficiency across the analyzed examples was documented at 82%, with deviations spanning from 70% to 90%, the average core area to gross floor area (GFA) ratio was determined to be 11%, ranging from 4% to 21%, and no substantial difference was noted in the impact of core arrangements on space efficiency, and parallel findings were observed for forms and construction materials. This article aspires to provide architectural designers with essential perspectives, assisting and directing them in the conception and realization of upcoming ventures both across Europe and internationally in this domain.
Polysulfur Copolymer as a Support Material for the Preparation of a Novel Multifunctional Photocatalytic Composite Material
(Springer, 2025) Kesimal, Busra; Guner, Zuhal Vanli; Cihaner, Atilla; Kaya, Murat
One-step addition of magnetic nanoparticles and titanium dioxide nanoparticles into polysulfur copolymer as cheap and available support was reported for the first time to prepare the magnetically separable heterogeneous catalyst, PolyS-MNP-TiO2. The photocatalytic activities of the PolyS-MNP-TiO2 composite material and its constituents were examined in the methylene blue (MB) degradation, textile-based wastewater simulant, exposed to solar light. Detailed characterization of the catalysts was performed with SEM, TEM, and EDX measurements. The photocatalytic activity of the resulting composite was figured out in the removal of methylene blue dye by using a solar simulator. Significantly, the as-prepared PolyS-MNP-TiO2 exhibits exceptional photocatalytic activity and total degradation of dye molecules was achieved in 60 min. Additionally, the prepared novel photocatalyst showed enhanced stability and reusability due to the magnetic behavior of the composite material and the same portion of catalyst was used in five successive tries without apparent loss in catalytic activity by eliminating long and work-loaded processes like filtration and centrifugation.
Characterizations of the Commutators Involving Idempotents in Certain Subrings of $m_{2}(\mathbb{z})$
(Tubitak Scientific & Technological Research Council Turkey, 2023) Ozdin, Tufan; Gumusel, Gunseli
In this paper, we characterize the idempotency, cleanness, and unit-regularity of the commutator [E1, E2] = E1E2 - E2E1 involving idempotents E1, E2 in certain subrings of M2(Z).

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