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Article Citation - WoS: 4Citation - Scopus: 4Growth and Optical Characterization of Sn0.6sb0.4< Layer Single Crystals for Optoelectronic Applications(Elsevier Sci Ltd, 2022) Bektas, T.; Terlemezoglu, M.; Surucu, O.; Isik, M.; Parlak, M.SnSe compound is an attractive semiconductor material due to its usage in photovoltaic applications. The sub-stitution of Sb in the SnSe compound presents a remarkable advantage especially in point of tuning optical characteristics. The present paper reports the structural and optical properties of Sn1-xSbxSe (x = 0.4) layered single crystals grown by the vertical Bridgman method. To the best of our knowledge, this work is the first investigation of the Sn0.6Sb0.4Se crystal grown with the vertical Bridgman technique. X-ray diffraction (XRD) pattern of the grown crystal indicated the well crystalline structure of the grown crystals. Lattice strain and interplanar spacing of the crystal structure were determined using the XRD pattern. Scanning electron micro-scope images allowed to the observation of the layer crystal structure. The layer crystalline structure shows 2D material properties and provides 2D applications. Optical properties were revealed by carrying out Raman, ellipsometry and transmission measurements. Raman modes, refractive index, extinction coefficient, and dielectric spectra, band gap energy of the crystal were presented throughout the paper. The obtained results indicated that Sn1-xSbxSe (x = 0.4) layer single crystals may be an alternative potential for photovoltaic and optoelectronic applications.Article Citation - WoS: 44Citation - Scopus: 54Preparation and Photocatalytic Activity of G-c3n4< Heterojunctions Under Solar Light Illumination(Elsevier Sci Ltd, 2020) Gundogmus, Pelin; Park, Jongee; Ozturk, AbdullahThe solar light sensitive g-C3N4/TiO2 heterojunction photocatalysts containing 20, 50, 80, and 90 wt% graphitic carbon nitride (g-C3N4) were prepared by growing Titania (TiO2) nanoparticles on the surfaces of g-C3N4 particles via one step hydrothermal process. The hydrothermal reactions were allowed to take place at 110 degrees C at autogenous pressure for 1 h. Raman spectroscopy analyses confirmed that an interface developed between the surfaces of TiO2 and g-C3N4 nanoparticles. The photocatalyst containing 80 wt% g-C3N4 was subsequently heat treated 1 h at temperatures between 350 and 500 degrees C to improve the photocatalytic efficiency. Structural and optical properties of the prepared g-C3N4/TiO2 heterojunction nanocomposites were compared with those of the pristine TiO2 and pristine g-C(3)N(4 )powders. Photocatalytic activity of all the nanocomposites and the pristine TiO2 andg-C3N4 powders were assessed by the Methylene Blue (MB) degradation test under solar light illumination. g-C3N4/TiO2 heterojunction photocatalysts exhibited better photocatalytic activity for the degradation of MB than both pristine TiO2 and g-C3N4. The photocatalytic efficiency of the g-C3N4/TiO2 heterojunction photocatalyst heat treated at 400 degrees C for 1 his 1.45 times better than that of the pristine TiO2 powder, 2.20 times better than that of the pristine g-C3N4 powder, and 1.24 times better than that of the commercially available TiO2 powder (Degussa P25). The improvement in photocatalytic efficiency was related to i) the generation of reactive oxidation species induced by photogenerated electrons, ii) the reduced recombination rate for electron-hole pairs, and iii) large specific surface area.Article Linear Two-Dimensional Consecutive K-Type Systems in Multi-State Case(Elsevier Sci Ltd, 2026) Yi, He; Balakrishnan, Narayanaswamy; Li, XiangIn the context of consecutive k-type systems, multi-state system models are only considered in the onedimensional case and not in the two-dimensional case due to the complexity involved. In this paper, we consider several linear two-dimensional consecutive k-type systems in the multi-state case for the first time, as generalization of consecutive k-out-of-n systems and l-consecutive-k-out-of-n systems without/with overlapping. These systems include multi-state linear connected-(k, r)-out-of-(m, n): G systems, multi-state linear connected-(k, r)-or-(r, k)-out-of-(m, n): G systems, multi-state linear 1-connected-(k, r)-out-of-(m, n): G systems without/with overlapping, and multi-state linear 1-connected-(k, r)-or-(r, k)-out-of-(m, n): G systems without/with overlapping. We then derive their reliability functions by using the finite Markov chain imbedding approach (FMCIA) in a new way. We also present several examples to illustrate all the results developed here.Article Citation - WoS: 39Citation - Scopus: 48Understanding Key Skills for Information Security Managers(Elsevier Sci Ltd, 2018) Haqaf, Husam; Koyuncu, MuratInformation security management is a necessity for all institutions and enterprises that regard company information as valuable assets. Developing, auditing and managing information security depends upon professional expertise in order to achieve the desired information security governance. This research seeks the key skills required for the position of information security management as well as the methods to develop these skills through professional training programs. The study adopts the Delphi method which requires building a list of items through a literature survey and involves experts with certain expertise to modify the list until a consensus on less than 20% of the items is reached. Through completing three rounds of the Delphi technique - data collection, relevance voting and ranking sixteen skills are shortlisted as the key skills. In the final list, the majority belong to core information security skills, and the top two skills belong to project/process management skills and risk management skills, indicating the importance of these skills for the information security manager role. In addition, a series of related professional training programs and certifications are surveyed, the outcome of which highlights a number of most comprehensive and appropriate programs to develop these determined skills.Article Breaking the Cycle: A Systemic Analysis of Socio-Technical Barriers and Policy Priorities for Biomass Technology in an Emerging Economy(Elsevier Sci Ltd, 2026) Oztel, Ahmet; Erol, Ismail; Benli, Tolga; Ar, Ilker MuratThis study addresses the critical challenge of slow biomass technology adoption in emerging economies, using Türkiye-with a potential of 3.9 MToe annually-as a representative case. Despite its promise for clean energy and rural development, adoption is stifled by a complex web of socio-economic and cultural barriers. Moving beyond isolated analyses, this research employs a novel Interval-Valued Picture Fuzzy Interpretive Structural Modeling and Cross-Impact Matrix Multiplication Applied to Classification approach to model the interdependencies and uncertainties among 17 key barriers identified from literature and expert input. The findings of this study provide a strategic hierarchy for policymakers, revealing that weak regulatory frameworks, gender roles, health concerns, cultural taboos around waste use, and land-use conflicts are the fundamental driving barriers that perpetuate dependent challenges such as high costs and low awareness. To break this cycle, we propose a targeted policy framework prioritizing robust regulations with financial incentives, genderinclusive training programs, public health campaigns, and community-based ownership models. These interventions offer a systemic roadmap to accelerate sustainable biomass adoption, directly supporting progress towards UN Sustainable Development Goals 7 (Affordable and Clean Energy), 12 (Responsible Consumption), and 13 (Climate Action) in Türkiye and similar emerging economies where comparable socio-technical conditions prevail.Correction Characterization of Lead Glazed Potteries From Smyrna (izmir/Turkey) Using Multiple Analytical Techniques; Part I: Glaze and Engobe (vol 40, Pg 2143, 2014)(Elsevier Sci Ltd, 2014) Ozcatal, M.; Yaygingol, M.; Issi, A.; Kara, A.; Turan, S.; Okyar, F.; Minceva-Sukarova, B.[No Abstract Available]Article Knee Hyperextension in Chronic Stroke: Associated Biomechanical and Neuromuscular Factors(Elsevier Sci Ltd, 2025) Korkusuz, Sueleyman; Korkusuz, Busra Seckinogullari; Ozgoren, Nihat; Aritan, Serdar; Ceren, Ali Naim; Topcuoglu, Mehmet Akif; Balkan, Ayla FilBackground: This study aimed to determine the gait phase in which knee hyperextension occurs in stroke patients and to investigate the factors associated with knee hyperextension. Methods: This study included 30 stroke patients aged between 40 and 70 years with maximum knee hyperextension during the stance phase of gait. Muscle strength was evaluated with manual muscle test, and muscle tone was assessed with the Modified Ashworth Scale. Kinematic evaluation of the patients was made using the motion analysis system. Additionally, categorisation was made according to the stance phase of gait, where knee hyperextension was at its highest. Findings: A weak relationship was found between maximum knee hyperextension angle and gastrocnemius spasticity, a moderate relationship between knee flexor muscle strength, and a moderate relationship between ankle dorsiflexor muscle strength. In addition, a weak relationship was found between the maximum knee hyperextension and pelvic retraction angles. According to this clustering, it was observed that 66.67 % of the participants (20 people) showed maximum knee hyperextension in the single support phase. It was observed that the participants who had maximum knee hyperextension, especially after the mid-stance phase, had higher mean gastrocnemius spasticity. It was also observed that participants in Cluster 4, with a greater amount of maximum knee hyperextension, had the worst clinical parameters. Interpretation: Our study observed that the degree of maximum knee hyperextension was related to knee flexor and ankle dorsiflexor muscle strengths, gastrocnemius spasticity and pelvic retraction. As clinical parameters worsened, maximum knee hyperextension was thought to occur late in the stance phase. Clinical Trial code: NCT05679700Article A New Method To Determine the Continuous Refractive Index of an Absorbing Film by Generalized Stockwell Transform(Elsevier Sci Ltd, 2023) Coskun, Emre; Emir, Cansu; Selamet, Semanur; Parlak, Mehmet; Ozder, SerhatGeneralized Stockwell Transform (GST) was adapted to analyze a transmittance signal to continuously determine the refractive index and extinction coefficient. The process is built by analyzing oscillation frequencies of the transmission signal where oscillations exist. The simulation studies clearly show the advantage of the locally referenced phase property of the presented method. The validity of the method was checked for a CdS thin film. The results determined by the GST method are consistent with the results determined by envelope and other signal analyzing methods, and the literature. The noise and relative error analysis of the method was also discussed.Article Citation - WoS: 7Citation - Scopus: 6Temperature-Dependent Structural Transition, Electronic Properties and Impedance Spectroscopy Analysis of Tl2ingas4< Crystals Grown by the Bridgman Method(Elsevier Sci Ltd, 2018) Qasrawi, A. F.; Alkarem, Qotaibah A.; Gasanly, N. M.In this work, we report the temporary structural modifications associated with the in situ heating of the Tl2InGaS4 crystals in the temperature range of 300-420 K. The analysis of the X-ray diffraction patterns revealed the temperature-independent possible phase transformations between the monoclinic and triclinic phases. The temperature analysis of the lattice parameters, crystallite size, strain, dislocation density and stacking faults has shown a temporary enhancement in the crystallinity of this compound above 375 K. Significant increase in the grain size accompanied to decrease in the strain, defect density and stacking faults was observed above this temperature. The scanning electron microscopy imaging has shown that the crystals are layer structured with high quality layers of thicknesses of similar to 12 nm. In addition the energy dispersive X-ray analysis has shown that the crystal comprise no detectable impurity. Moreover, the room temperature optical characterizations has shown that the Tl2InGaS4 exhibit an energy band gap of 2.5 eV. The temperature dependent electrical resistivity measurements indicated highly resistive crystal with activation energy values of 0.84 and 0.19 eV above and below 375 K, respectively. On the other hand, room temperature impedance spectroscopy analysis in the frequency domain of 10-1800 MHz has shown that the crystal exhibits negative resistance and negative capacitance effects below and above 1580 MHz. The crystals are observed also to behave as band stop filter with notch frequency of 1711 MHz.Article Citation - WoS: 7Citation - Scopus: 10Improving Sleep-Wake Behaviors Using Mobile App Gamification(Elsevier Sci Ltd, 2022) Ilhan, Ayse Ezgi; Sener, Bahar; Hacihabiboglu, HuseyinGamification can be used to encourage people to perform challenging tasks. Gamification can also be useful in altering unwanted habits and enhancing subjective well-being. Everyday health is affected by sleep-wake habits to a significant extent. Therefore, we can come across gamified products and mobile applications related to subjective well-being and sleep/wake activities. This paper presents a study investigating whether gamification can be used to affect sleep-wake behaviors in a positive way. The paper presents a quantified relationship between wake-up, go-to-sleep, work (start) hours and gamified features. For this purpose, a gamified mobile alarm clock application called the Sleepy Bird was designed, created and tested in a user study. The study included twenty-six participants in an A-B experimental set-up: thirteen participants using a gamified version and thirteen participants using a non-gamified version of the app for two weeks. The participants who used the non-gamified version had a poorer motivation to begin their day at the required times in comparison to those who used the gamified version. It was also observed that gamification made favorable modifications to participants' sleep-wake behaviors.
