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Review Citation - WoS: 3Citation - Scopus: 3Spatial Effectiveness in High-Rise Timber Towers: a Global Perspective(Mdpi, 2024) Ilgin, Huseyin Emre; Aslantamer, Ozlem NurHigh-rise timber structures signify a rising trend, thanks to their significant environmental and economic advantages that occur over their complete lifespan. Enhancing spatial effectiveness in these structures is a critical design consideration for project feasibility. Currently, there has been no comprehensive study on the space efficiency of such towers. This article analyzed 79 cases all over the world to deepen the knowledge of design features shaping spatial efficiency. The critical findings are as follows: (1) the most common architectural preferences include residential function, a centrally located service core, and prismatic arrangements; (2) the preferred structural material is composite, while a shear walled frame system is the favored structural system; (3) the average spatial efficiency and percentage of core area to GFA were recorded at 84% and 10%, ranging from the lowest values of 70% and 4% to the highest values of 95% and 21%, respectively; and (4) no significant differences were detected in the effect of core design approaches on spatial effectiveness if appropriately planned, with similar inferences drawn concerning form and the structural material used. This article will assist in developing design directions for different interested parties, including architectural designers taking part in the advancement of high-rise timber towers.Article Citation - WoS: 1Outperformance of CaO-Incorporated Alumina-Supported Pd Catalysts in Methanol Decomposition(Springer, 2025) Eryildirim, Busra; Oktar, Nuray; Dogu, DorukThis study aimed to investigate the impact of CaO incorporation to alumina-supported Pd catalysts on the methanol decomposition reaction. For this purpose, mayenite, alumina and/or calcium oxide-supported Pd catalysts were synthesized. The synthesized catalysts were characterized by XRD, FTIR, Laser Raman spectroscopy, N2 adsorption-desorption, pyridine adsorbed DRIFTS, CO2-TPD, XPS, SEM-EDS, and ICP-OES techniques. Catalytic activity tests were carried out over a 6 h reaction period in the range of 100-400 degrees C. The results of the characterization and activity tests showed that the addition of CaO had significant effects on the physicochemical properties of the catalyst as well as on the catalytic activity. By adding CaO to the alumina support material, the acidity was reduced, thus reducing the selectivity for dimethyl ether (DME) formation, which is significantly high for the 1Pd@Al2O3 catalyst, and increasing the H2 and CO selectivity. The mayenite-supported catalyst (1Pd@SGM), which contains alumina and calcium oxide in its unique crystal structure, showed an excellent catalytic performance close to complete methanol conversion with DME selectivity below 1% at 400 degrees C. In the stability test carried out at 350 degrees C for 6 h with 1Pd@Al2O3, 1Pd@SGM, and 1Pd@48CaO@Al2O3 catalysts used in the temperature scan, it was concluded that all catalysts were stable and 1Pd@SGM catalyst showed higher catalytic activity than the others.Article Citation - WoS: 13Citation - Scopus: 13A Systematic Approach To Optimizing Energy-Efficient Automated Systems With Learning Models for Thermal Comfort Control in Indoor Spaces(Mdpi, 2023) Erisen, SerdarEnergy-efficient automated systems for thermal comfort control in buildings is an emerging research area that has the potential to be considered through a combination of smart solutions. This research aims to explore and optimize energy-efficient automated systems with regard to thermal comfort parameters, energy use, workloads, and their operation for thermal comfort control in indoor spaces. In this research, a systematic approach is deployed, and building information modeling (BIM) software and energy optimization algorithms are applied at first to thermal comfort parameters, such as natural ventilation, to derive the contextual information and compute the building performance of an indoor environment with Internet of Things (IoT) technologies installed. The open-source dataset from the experiment environment is also applied in training and testing unique black box models, which are examined through the users' voting data acquired via the personal comfort systems (PCS), thus revealing the significance of Fanger's approach and the relationship between people and their surroundings in developing the learning models. The contextual information obtained via BIM simulations, the IoT-based data, and the building performance evaluations indicated the critical levels of energy use and the capacities of the thermal comfort control systems. Machine learning models were found to be significant in optimizing the operation of the automated systems, and deep learning models were momentous in understanding and predicting user activities and thermal comfort levels for well-being; this can optimize energy use in smart buildings.Article Citation - WoS: 21Citation - Scopus: 21A Study on the Dark and Illuminated Operation of Al/Si3< Schottky Photodiodes: Optoelectronic Insights(Springer Heidelberg, 2024) Surucu, Ozge; Yildiz, Dilber Esra; Yildirim, MuratThis work extensively investigates the operation of an Al/ Si3N4/p-Si Schottky-type photodiode under dark and varying illumination intensities. The photodiode is fabricated by employing the metal-organic chemical vapor deposition (MOCVD) method. A thorough electrical characterization is performed at room temperature, encompassing measurements of current-voltage (I-V), current-time (I-t), capacitance-time (C-t), and conductance time (G-t). The photodiode's rectification factor and reverse bias area increased under illumination. The relationship between light power density, barrier height, and diode ideality factor is found. The study also found a strong correlation between light intensity and applied voltage on series resistance (R-s) and shunt resistance (R-sh). R-s values are calculated using Cheung's functions, revealing the diode's resistance behavior. The study also examines the photodiode's photoconductivity and photoconductance, finding a non-linear relationship between photocurrent and illumination intensity, suggesting bimolecular recombination. Calculated photosensitivity (K), responsivity (R), and detectivity (D*) values show the device's light response effectiveness, but efficiency decreases at higher illumination intensities. Transient experiments indicate stable and reproducible photocurrent characteristics, revealing photogenerated charge temporal evolution. This study provides a complete understanding of the Al/Si3N4/p-Si Schottky photodiode's behavior under different illumination intensities. The findings advance optoelectronic device knowledge and enable their use in advanced technologies.Article Citation - Scopus: 3Complete Characterization of a Class of Permutation Trinomials in Characteristic Five(Springer, 2024) Grassl,M.; Özbudak,F.; Özkaya,B.; Temür,B.G.In this paper, we address an open problem posed by Bai and Xia in [2]. We study polynomials of the form f(x)=x4q+1+λ1x5q+λ2xq+4 over the finite field F5k, which are not quasi-multiplicative equivalent to any of the known permutation polynomials in the literature. We find necessary and sufficient conditions on λ1,λ2∈F5k so that f(x) is a permutation monomial, binomial, or trinomial of F52k. © The Author(s) 2024.Article On the Lupas q-transform of Unbounded Functions(Walter de Gruyter Gmbh, 2023) Ostrovska, Sofiya; Turan, MehmetThe Lupa , s q-transform comes out naturally in the study of the Lupa , s q-analogue of the Bernstein operator. It is closely related to the Heine q-distribution which has a numerous application in q-boson operator calculus and to the Valiron method of summation for divergent series. In this paper, the Lupa , s q-transform (lambda(q)f)(z), q is an element of (0, 1), of unbounded functions is considered in distinction to the previous researches, where only the case f is an element of C[0, 1] have been investigated. First, the condition for a function to possess the Lupa , s q-transform is presented. Also, results concerning the connection between growth rate of the function f (t) as t -> 1(-) and the growth of its Lupa , s q-transform (lambda(q)f)(z) as z -> infinity are established. (c) 2023 Mathematical Institute Slovak Academy of SciencesArticle Citation - WoS: 5Citation - Scopus: 3Investigation of Λ (1405)as a molecular pentaquark state(Springer, 2024) Azizi, K.; Sarac, Y.; Sundu, H.Lambda ( 1405 ) is one of the interesting particles with its unclear structure and distinct properties. It has a light mass compared to its non-strange counterpart, despite the strange quark it carries. This situation puts the investigation of this resonance among the hot topics in hadron physics and collects attention to clarify its properties. In this study, we focus on the calculation of the mass and residue of the Lambda ( 1405 ) resonance within the framework of QCD sum rules. We assign a structure in the form of a molecular pentaquark composed from admixture of K - meson-neutron. Using an interpolating current in this form, the masses and the current coupling constant are attained as m = 1406 +/- 128 MeV and lambda = ( 3.35 +/- 0.35 ) x 10( - 5) GeV 6 for q and m = 1402 +/- 141 MeV and lambda = ( 4.08 +/- 1.08 ) x 10( - 5) GeV 6 for I Lorentz structures entering the calculations, respectively. The obtained mass values agree well with the experimental data supporting the plausibility of the considered structure.Article Citation - WoS: 10Citation - Scopus: 11Analysis of Space Efficiency in High-Rise Timber Residential Towers(Mdpi, 2024) Ilgin, Hueseyin Emre; Aslantamer, Ozlem NurHigh-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.Article Citation - WoS: 1Citation - Scopus: 2Diffusion of Digital Authoritarianism? Censorship, Surveillance and Beyond in Türkiye(Routledge Journals, Taylor & Francis Ltd, 2024) Aslan, Mesut; Yilmaz, GozdeThe expansion of authoritarianism in the world has led to increased debates about digital authoritarianism as well as the diffusion of authoritarianism. However, these two topics have not been addressed together despite the digital world being a strong candidate for diffusion. This study explores whether digital authoritarian diffusion occurs from China and/or Russia to T & uuml;rkiye by examining the models of China and Russia and unpacking the Turkish model of digital authoritarianism. We argue that the Turkish model is inspired by the Chinese and Russian models, but without the active promotion of those models by authoritarian centres. Instead, analyses of the legal framework, technology and surveillance practices suggest that there is an indirect and passive as well as internally driven process at work.Article Citation - WoS: 7Citation - Scopus: 10Space Efficiency in North American Skyscrapers(Mdpi, 2024) Ilgin, Huseyin Emre; Aslantamer, Ozlem NurSpace 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.