188 results
Search Results
Now showing 1 - 10 of 188
Article 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.Article Citation - WoS: 13Citation - Scopus: 14Linear and Nonlinear Optical Properties of Bi12geo20 Single Crystal for Optoelectronic Applications(Elsevier Sci Ltd, 2023) Isik, M.; Gasanly, N. M.The present paper aims at presenting linear and nonlinear optical properties of Bi12GeO20 single crystals grown by Czochralski method. Transmission and reflection measurements were performed in the 400-1000 nm region. The recorded spectra were analyzed considering well-known optical models. Spectral dependencies of absorption coefficient, skin depth, refractive index, real and imaginary components of dielectric function were presented. The analyses performed on absorption coefficient showed direct bandgap and Urbach energies as 2.56 and 0.22 eV, respectively. The first-and third-order nonlinear susceptibilities and nonlinear refractive index of the crystal were also reported in the present work. The results of the present paper would provide valuable information for optoelectronic device applications of Bi12GeO20.Article Citation - WoS: 23Citation - Scopus: 25Investigation of Optical Properties of Bi12geo20< Sillenite Crystals by Spectroscopic Ellipsometry and Raman Spectroscopy(Elsevier Sci Ltd, 2020) Isik, M.; Delice, S.; Gasanly, N. M.; Darvishov, N. H.; Bagiev, V. E.Bi12GeO20 (BGO) compound is one of the fascinating members of sillenites group due to its outstanding photorefractive and photocatalytic characteristics. The present paper aims at investigating optical properties of BGO crystals by means of spectroscopic ellipsometry and Raman spectroscopy measurements. Bi12GeO20 single crystals grown by Czochralski method were structurally characterized by X-ray diffraction (XRD) experiments and the analyses showed that studied crystals have cubic crystalline structure. Raman spectrum exhibited 15 peaks associated with A, E and F modes. Spectroscopic ellipsometry measurement data achieved in the energy region between 1.2 and 6.2 eV were used in the air/sample optical model to get knowledge about complex pseudodielectric constant, pseudorefractive index, pseudoextinction and absorption coefficients of the crystals. Spectral change of real and imaginary part of complex pseudodielectric constant were discussed in detail. Band gap energy of Bi12GeO20 single crystals was calculated to be 3.18 eV using absorption coefficient dependency on photon energy. Critical point energies at which photons are strongly absorbed were determined by utilizing the second energy derivative spectra of components of complex pseudodielectric function. Fitting of both spectra resulted in the presence of four interband transitions with energies of 3.49, 4.11, 4.67 and 5.51 eV.Article Citation - WoS: 88Citation - Scopus: 105Industry 4.0 Technologies, Sustainable Operations Practices and Their Impacts on Sustainable Performance(Elsevier Sci Ltd, 2023) Yavuz, Oguzhan; Uner, M. Mithat; Okumus, Fevzi; Karatepe, Osman M.Using a natural resource-based view and technology-organization-environment framework as the theoretical focus, this paper develops and tests a research model in which sustainable operations practices mediate the impact of industry 4.0 technologies on sustainable performance. The model also tests sustainable operations practices as a moderator of the effect of industry 4.0 technologies on sustainable performance. Data obtained from 302 participants in Turkey's technology development regions were utilized to gauge the aforesaid linkages via partial least squares structural equation modeling. As predicted, sustainable operations practices mediate the influence of industry 4.0 technologies on sustainable performance. Contrary to the study prediction, sustainable operations practices do not significantly moderate the impact of industry 4.0 technologies on sustainable performance. Theoretical and practical implications are discussed and future research directions are offered.Article Citation - WoS: 5Citation - Scopus: 6Analyzing Two Decades of Intimate Partner Femicide-Suicides in T?rkiye*(Elsevier Sci Ltd, 2023) Cavlak, Mehmet; Odabasi, Aysun Balseven; Mutlu, Niluefer Dilara Ar; Erbaydar, Nueket PaksoyIntimate partner femicide-suicide (IPF-S) is an understudied subgroup of homicide-suicide deaths. Limited research has been conducted on IPF-Ss in the Eastern Mediterranean region. This study thus aimed to evaluate the characteristics of IPF-Ss that occurred in Turkiye between 2000 and 2019. IPF-Ss (n = 226) were extracted from electronic news stories. Data on victims, perpetrators, their relationships, and incidents of murder and suicide were collected. Descriptive statistics were calculated, and logistic regression analysis, mortality rates, and proportion of IPF-S in femicide calculations were conducted, showing that 13.3% of the femicides (n = 1699) were IPF-Ss. The IPF-Ss increased in 5-year intervals and were the highest during the 2015-2019 period (62.5%). Victims were married in 48.2% of the cases and 56% were aged <35 years, while 51.3% of the perpetrators were married and 52.6% were aged >40 years. In 42.0% of the cases, the perpetrator lived with the victim. Most (79.2%) of the cases took place in urban settlements, and the perpetrators used firearms in 84.1% of femicide cases. Firearm use was the most common method in cases where IPF-S was planned (OR = 2.98), when the IPF-S method was the same (OR = 29.6), and when the perpetrator committed suicide (OR = 7.82). In addition, it was found that firearm ownership is an important risk factor for IPF-S in Turkiye. Therefore, we recommend legislation to restrict firearms, as well as new measures to prevent illegal access to weapons.Article Citation - WoS: 5Citation - Scopus: 6Pressure Injury Knowledge of Turkish Internship Nursing Students(Elsevier Sci Ltd, 2021) Sonmez, Munevver; Tasdemir, Nurten; Oren, NursenAim: This study aimed to describe the pressure injury (PI) knowledge of Turkish internship nursing students (INSs). Materials and methods: This descriptive study was performed using the Turkish version of the Modified Pieper Pressure Ulcer Knowledge Test. The study population consisted of INSs in a nursing program in the West Black Sea Region, Turkey. The sample of the study was 278 (74.1% of a total of 375 volunteer INSs). Results: The mean knowledge test score was 29.03 +/- 7.15 (range 11-44). The prevention/risk score was higher; only 28.4% of the students had a satisfactory test score. Conclusion: The results of this study indicated that the INSs had significant knowledge gaps regarding PI. Nursing students' knowledge deficiencies regarding PIs should be identified at undergraduate level, and the necessary educational measures should be taken.Article Citation - WoS: 1Citation - Scopus: 3Enhancing Language Proficiency Through Mobile Extensive Listening and Podcasting: a Multifaceted Approach To Metacognition and Critical Thinking(Elsevier Sci Ltd, 2024) Sendag, Serkan; Caner, Mustafa; Gedik, Nuray; Toker, SacipMobile-assisted language learning (MALL) has gained considerable attention in foreign and second-language education. As part of a two-year project, this study employed a mixed-methods research design with 60 B2-level learners of English as a foreign language. The primary purpose of this study is to investigate the impact of repetitive listening and listening duration on participants' listening comprehension, speaking, critical thinking, listening strategies, and self-regulated learning strategies. The participants were divided into two groups, with the experimental group (n = 30) participating in the innovative Mobile Extensive Listening and Podcasting (MELAP) intervention. MELAP is a novel approach within the MALL framework that involves extensive listening to podcasts in the target language, content creation, and podcasting. The ten-week treatment revealed that unlike in previous studies, our experimental group improved not only in listening comprehension but also demonstrated significant gains in speaking skills and critical thinking. Notably, enhanced critical thinking skills were observed, correlated with an increased total listening duration and repeated extensive listening. Qualitative data analysis sheds light on how participants viewed the MELAP intervention, revealing what motivated them, what distractions they faced, and their opinions on developing and sharing podcasts. These findings emphasize the potential of the MELAP to enhance language skills and foster critical thinking in language learners, contributing to the ongoing discourse on the effectiveness of MALL.Article Citation - WoS: 2Citation - Scopus: 2Characterization of the Mgo/Gase0.5< Heterojunction Designed for Visible Light Communications(Elsevier Sci Ltd, 2015) Qasrawi, A. F.; AlGarni, S. E.; Gasanly, N. M.In this study an optoelectronic design is reported and characterized. The device is made of p-type MgO solved in sodium silicate binder and n-type GaSe0.5S0.5 heterojunction. It is described by means of X-ray diffraction, optical absorption and reflection in the incident light wavelength range of 190-1100 nm and by means of dark and 406 nm laser excited current (I)-voltage (V) characteristics. The optical reflectance was also measured as a function of angle of incidence of light in the range of 35-80. The structural analysis revealed no change in the existing phases of the device composers. In addition, it was observed that for pure sodium silicate and for a 67% content of MgO solved in sodium silicate binder (33%), the heterojunction exhibits a valence band shift of 0.40 and 0.70 eV, respectively. The painting of MgO improved the light absorbability significantly. On the other hand, the angle-dependent reflectance measurements on the crystal displayed a Brewster condition at 70. The MgO/ GaSe0.5S0.5 heterojunction exhibited no Brewster condition when irradiated from the MgO side. Moreover, for the crystal and the MgO/ GaSe0.5S0.5 heterojunction, the dielectric spectral analysis revealed a pronounced increase in the quality factor of the device. The I-V characteristics of the device revealed typical optoelectronic properties with high photo-response that could amplify the dark current 24 times when irradiated with 5 mW power laser light. The structural, optical, dielectric and electrical features of the MgO/GaSe0.5S0.5 heterojunction nominate it for use in visible light communication technology. (C) 2015 Elsevier Ltd. All rights reserved.
