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Article Citation - WoS: 19Citation - Scopus: 19A 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 A Factory in a Time of Turmoil: The Establishment and Engineering of the Büyükdere Match Factory in 1930s Istanbul(MDPI, 2025) Tunc, Gokhan; Tunc, Tanfer EminThe Republic of Turkey established its first match factory in Sinop in 1929 but had to relocate it even before it was in operation due to severe structural damage caused by ground settlement. In July 1930, through his US-based firm the American-Turkish Investment Corporation (ATIC), the Swedish "Match King" Ivar Kreuger signed a contract with the Republic of Turkey to build and operate a factory in B & uuml;y & uuml;kdere, Istanbul. By 1930, Kreuger had already established a match production monopoly in nearly every country in Europe and that year created a similar financial system for Turkey, gaining control of match production for 25 years. This article explains the events surrounding the establishment of his modern production facility in Turkey, with a particular focus on its engineering aspects. It details the strategically chosen location, the engineering solutions for the factory's construction, its production lines, and what the country gained and lost from it. In order to determine the establishment and production processes of the facility, the authors examined domestic and foreign archival documents, firsthand news reports from the period, articles and theses, and all other available documents. After the contract was terminated by both parties, the Turkish government and ATIC, in May 1943, the factory continued its production and storage activities until May 1989. At that point, the factory and all its equipment were integrated into another existing facility in the & Idot;neg & ouml;l district of Bursa province. Almost all the buildings of the B & uuml;y & uuml;kdere Match Factory were demolished, and the land was repurposed for a 450-bed regional hospital in 2012. In short, this article deploys the B & uuml;y & uuml;kdere Match Factory as a case study to examine what Turkey gained and lost from the establishment and production processes of a modern industrial factory, enabled by US-Turkish collaboration, and equipped with the most advanced manufacturing and engineering technologies of the time.Article Citation - WoS: 1Citation - Scopus: 1Flame Retarded Plasticized Poly(lactic Acid) Using Phosphorus-Based Additives(Sage Publications Ltd, 2024) Yesil, Sertan; Aytac, Ayse; Selim, FatmaIn this study, the synergistic effect of the flame-retardant additives on the properties of poly(lactic acid) (PLA) was investigated and at the same time, it was tried to increase the toughness of PLA by adding small amounts of phosphate-based additives to plasticized PLA as binary and ternary mixtures. Poly(ethylene glycol) (PEG) was used as a plasticizer. As flame retardant additives, ammonium polyphosphate (APP), tri-phenyl phosphate (TPP), and boron phosphate (BP) were used. Characterization of the composites was carried out by tensile test, impact test, differential scanning calorimetry (DSC), thermal gravimetric analyses (TGA), scanning electron microscopy (SEM), limiting oxygen index (LOI), and UL-94 horizontal burning tests. In addition, TGA-FTIR analyses were carried out to understand the thermal degradation mechanism of composites during combustion. According to the SEM micrographs of the burnt surfaces of the samples, a smooth and flat structure is observed in PLA/PEG/5TPP-5BP sample, while a porous structure and branching formations are observed in other composite samples. Among the composite samples, the best flame retardancy features were observed in the composite containing PLA/PEG/5APP-2.5TPP-2.5BP sample, and the highest impact strength and elongation at break values were obtained in the composite containing PLA/PEG/5APP-5TPP sample.Article Citation - WoS: 11Citation - Scopus: 12Analysis of the Structural and Optical Characteristics of Znse Thin Films as Interface Layer(Springer, 2025) Emir, C.; Tataroglu, A.; Gökmen, U.; Ocak, S.B.This research reveals the results of a comprehensive analysis of the optical and structural features of zinc selenide (ZnSe) thin film. The studied film was synthesized using the thermal evaporation method after preparation on the glass substrate. The film’s structural characteristics, which have been determined by using scanning electron microscopy (SEM), energy dispersive X-ray (EDX), and X-ray diffraction (XRD), confirm the polycrystalline nature of the films with a predominant cubic zinc-blende structure. The surface morphology investigated through SEM reveals a uniform grain distribution with minimal surface defects, indicating high-quality film formation. In order to examine the optical characteristics, the ultraviolet–visible spectroscopy method is used in a spectral range between 300 and 900 nm. In this way, the ultraviolet–visible spectroscopy data are utilized to obtain optical features such as extinction coefficient (k), optical band gap (Eg), refractive index (n), absorption coefficient (α), and optical conductivity (σopt). These optical properties are assessed using ultraviolet–visible spectroscopy, revealing a direct band gap of approximately 2.88 eV, which is consistent with the bulk properties of ZnSe and suitable for optoelectronic applications. The results of this study clearly show that the studied ZnSe film can be used for optoelectronic device applications. © The Author(s) 2025.Article Citation - WoS: 2Citation - Scopus: 2A Comparative Analysis of the Criteria for Choosing Sustainable Materials for Façades in Turkey and the European Union(Mdpi, 2024) Daskin, Haney Basak; Barbulescu, Alina; Muntean, Radu; Akcay, Emre CanerOne of the primary contributors to energy consumption is the construction industry. To address the urgent demand for eco-friendly approaches in this field, this study conducted an investigation on Scopus and Web of Science databases to identify the criteria for selecting sustainable materials for facades. Three groups of criteria were derived after a systematic review: Environmental, Social/economic and Technical. The main goal of the research was to answer the question of whether there are differences in these materials' selection between Turkey and European Union countries. After applying statistical tests, it was found that there are significant differences in selecting eco-friendly material only from the social/economic perspective. The most important sub-criterion is the economic cost. Comparisons with results from China and US confirm this finding.Article Citation - WoS: 8Citation - Scopus: 10Computing Reliability Indices of a Wind Power System Via Markov Chain Modelling of Wind Speed(Sage Publications Ltd, 2024) Eryilmaz, Serkan; Bulanik, Irem; Devrim, YilserStatistical 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.Article 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: 9Citation - Scopus: 10Analysis 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.