Atılım Üniversitesi / Atılım University
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Article Citation Count: 1Acceptance of Educational Use of AI Chatbots in the Context of Self-Directed Learning with Technology and ICT Self-Efficacy of Undergraduate Students(Taylor & Francis inc, 2024) Küçükergin, Kemal Gürkan; Gokcearslan, Sahin; Eşiyok, Elif; Tourism Management; Public Relations and AdvertisingFor long now, the use of Artificial Intelligence (AI) chatbots in higher education to support and engage learners in classroom learning activities has been attracting the attention of researchers. The acceptance of this technology for learning purposes is indicative of learners' intentions and actual use in the future. Hence, this study aims to test the educational use of AI chatbots in the context of self-directed learning with technology (SDLT) along with information and communication technology (ICT) self-efficacy, using the extended Technology Acceptance Model (TAM). The study involved 414 undergraduate students, and the research model was tested by utilizing the Partial Least Square Structural Equation Model (PLS-SEM). The results indicate that ICT self-efficacy affects only the perceived ease of use (PEU), whereas PEU and perceived usefulness have a positive effect on the intention to use AI chatbots. Moreover, SDLT is shown to affect both the intention and the actual use of AI chatbots. As such, it is suggested - among other notes - that universities update their curricula and activities to support SDLT, and also organize activities in order to increase ICT self-efficacy among students.Article Citation Count: 31Adoption of mobile applications for teaching-learning process in rural girls' schools in India: an empirical study(Springer, 2020) Mısra, Sanjay; Majumdar, Dipasree; Misra, Sanjay; Damasevicius, Robertas; Computer EngineeringThe purpose of this study is to identify the factors that can impact the adoption of mobile apps for teaching-learning process focusing on the girls' school in rural India. The hypotheses were proposed and a conceptual model has been developed. There is a survey work conducted to collect the data from different respondents using a convenience sampling method. The model has been validated statistically through PLS-SEM analysis covering feedbacks of 271 effective respondents. The study highlights the impact of different antecedents of the behavioural intention of the students of using mobile applications for teaching-learning process. The results also show that among other issues, price value has insignificant influence on the intention of the girl students of the rural India. During survey feedbacks have been obtained from the 271 respondents, which is meagre compared to vastness of the population and school of rural India. Only few predictors have been considered leaving possibilities of inclusion of other boundary conditions to enhance the explanative power more than that has been achieved in the proposed model with the explanative power of 81%. The model has provided laudable inputs to the educational policy makers and technology enablers and administrators to understand the impact of the mobile applications on the rural girls' school of India and facilitate the development of m-learning. Very few studies been conducted to explore the impact of mobile applications on the school education of rural India especially focusing on the girls' schools.Article Citation Count: 21Agriculture 4.0: An Implementation Framework for Food Security Attainment in Nigeria's Post-Covid-19 Era(Ieee-inst Electrical Electronics Engineers inc, 2021) Mısra, Sanjay; Misra, Sanjay; Fernandez-Sanz, Luis; Computer EngineeringThe challenge of Nigeria's food insecurity in the era of the Covid-19 pandemic, insecurity, climate change, population growth, food wastage, etc., is a demanding task. This study addresses Nigeria's food insecurity challenges by adopting agriculture 4.0 and commercial farming. Using data from six digital libraries, the Nigerian Bureau of Statistics, and other internet sources, we conducted a Systematic Literature Review (SLR using PRISMA) on Nigeria's agriculture, food security, and agriculture 4.0. Our results show Nigeria's current agricultural state, threats to food security, and modern digital agriculture technologies. We adapted our SLR findings to develop an implementation framework for agriculture 4.0 in solving Nigeria's food insecurity challenge in the post-Covid-19 era. Our proposed framework integrates precision agriculture in Nigeria's food production and the necessary enabling digital technologies in the agri-food supply chain. We analyzed the critical implementation considerations during each agri-food supply chain stage of farming inputs, farming scale, farming approach, farming operation, food processing, food preservation/storage, distribution/logistics, and the final consumers. This study will help researchers, investors, and the government address food security in Nigeria. The implementation of agriculture 4.0 will substantially contribute to SDG 2 (zero hunger), SDG 3 (good health and well-being), and SDG 8 (decent work and economic growth) of #Envision 2030 of the United Nations, for the benefit of Nigeria, Africa, and the entire world.Article Citation Count: 6Al/CdSe/GaSe/C resonant tunneling thin film transistors(Elsevier Science Bv, 2017) Qasrawı, Atef Fayez Hasan; Kayed, T. S.; Kayed, Tarek Said; Department of Electrical & Electronics EngineeringAn Al/CdSe/GaSe/C thin film transistor device was prepared by the physical vapor deposition technique at a vacuum pressure of 10(-5) mbar. The x-ray diffraction measurements demonstrated the polycrystalline nature of the surface of the device. The de current-voltage characteristics recorded for the Al/CdSe/C and Al/CdSe/GaSe/C channels displayed a resonant tunneling diode features during the forward and reverse voltage biasing, respectively. In addition, the switching current ratio of the Al/CdSe/C increased from 18.6 to 9.62x10(3) as a result of the GaSe deposition on the CdSe surface. Moreover, the alternating electrical signal analyses in the frequency range of 1.0 MHz to 1.8 GHz, showed some remarkable properties of negative resistance and negative capacitance spectra of the AVCdSe/GaSe/C thin film transistors. Two distinct resonance-antiresonance phenomena in the resistance spectra and one in the capacitance spectra were observed at 0.53, 1.04 and 1.40 GHz for the Al/CdSe/C channel, respectively. The respective resonating peak positions of the resistance spectra shift to 0.38 and 0.95 GHz when GaSe is interfaced with CdSe. These features of the thin film transistors are promising for use in high quality microwave filtering circuits and also for use as ultrafast switches.Article Citation Count: 14Al/MoO3/ZnPc/Al Broken Gap Tunneling Hybrid Devices Design for IR Laser Sensing and Microwave Filtering(Ieee-inst Electrical Electronics Engineers inc, 2020) Qasrawı, Atef Fayez Hasan; Khanfar, Hazem K.; Department of Electrical & Electronics EngineeringHerein the design of broken gap heterojunction devices made of molybdenum trioxide and zinc phthalocyanine coated onto Al substrates are reported. The devices which are prepared by the thermal evaporation technique under vacuum pressure of 10(-5) mbar are observed to exhibit a conduction and valence band offsets of 3.36 and 3.56 eV, respectively. The heterojunction devices are observed to form a subband gap of 0.66 eV between the valence bands edges of p- ZnPc and conduction bands edges of p-MoO3 leading to a p(+)/n(+) heterojunction type. Analysis of the current-voltage characteristics of the devices has shown that it exhibits tunneling diode characteristics with maximum tunneling barriers of width of similar to 45 nm. The device displayed biasing dependent photosensitivity in response to 850 nm laser lights. In addition to its characteristics as MOS device, when it was imposed with ac signals in the frequency domain of 0.01-1.80 GHz, it displayed resonance-antiresonancephenomena accompanied with negative capacitance effect in the studied range of spectra. The analysis of the alternating current (ac) electrical conductivity has shown that the ac conduction is mostly governed by quantum mechanical tunneling assisted with correlated barriers hopping. The laser light photosensitivity, the negative capacitance effect, the capacitance switching within 100 ns and the bandpass characteristics with notch frequency of 1.24 GHz make the Al/MoO3/ZnPc/Al attractive for use as IR sensors, parasitic capacitance cancellers, fast capacitance switches and microwave bandpass filters.Article Citation Count: 7Algorithm for adaptive learning process and improving learners' skills in Java programming language(Wiley, 2018) Mıshra, Alok; Arsic, Aleksandra; Domazet, Dragan; Mishra, Alok; Software EngineeringAdaptive approaches within distance learning systems enable adapting teaching process to the needs of each learner during the learning process. This paper presents an algorithm for creating an adaptive learning process that provides knowledge and skills improvement for learners in the Java programming language. Also, it presents the application of the tool that checks the learner's knowledge through solving practical tasks from the Java programming language. The adaptive learning process in this work leads the learner through teaching materials and practical tasks where the acquired knowledge is required to be applied. Also, the algorithm, based on the measurement of knowledge and time spent on a particular part of the learning process with detailed feedback and the demonstration of observed deficiencies, directs the learner to teaching materials that allow improving the demonstrated knowledge. Teaching materials are conceived as learning objects and, as such, allow for the application of adaptive approach. An analysis of the effectiveness of the algorithm and tool for practical knowledge testing from the Java programming language was done with a test group of learners who gave their opinions and grades.Article Citation Count: 75Analysis of Pc+(4380) and Pc+(4450) as pentaquark states in the molecular picture with QCD sum rules(Amer Physical Soc, 2017) Saraç Oymak, Yasemin; Sarac, Y.; Sundu, H.; Physics GroupTo better understand the nature and internal structure of the exotic states discovered by many collaborations, more information on their electromagnetic properties and their strong and weak interactions with other hadrons is needed. The residue or current coupling constant of these states together with their mass are the main inputs in determinations of such properties. We perform QCD sum rules analyses on the hidden-charm pentaquark states with spin parities J(P) = 3/2 (+/-) and J(P) = 5/2 (+/-) to calculate their residue and mass. In the calculations, we adopt a molecular picture for J(P) = 3/2(+/-) states and a mixed current in a molecular form for J(P) = 5/2(+/-). Our analyses show that the P-c(+) (4380) and P-c(+) (4450), observed by the LHCb Collaboration, can be considered as hidden-charm pentaquark states with J(P) = 3/2(-) and JP = 5/2(+), respectively.Article Citation Count: 3Analysis of the Junction Properties of C/GaSe0.5S0.5/C Back-to-Back Schottky-Type Photodetectors(Ieee-inst Electrical Electronics Engineers inc, 2015) Qasrawı, Atef Fayez Hasan; Qasrawi, Atef F.; Gasanly, Nizami M.; Department of Electrical & Electronics EngineeringIn this paper, a C/GaSe0.5S0.5/C metal-semiconductor-metal photodetector is suggested and described. The device is explored by means of current-voltage and capacitance-voltage (C-V) characteristics under different photoexcitation intensities. It was observed that the design of the back-to-back Schottky device has reduced the dark current of the normal Ag/GaSe0.5S0.5/C Schottky diode by 13 times and increased the photosensitivity from 3.8 to similar to 2.1x10(3). The device exhibited a barrier height of 0.842 eV in the dark. The barrier height is reduced via photoexcitation. In addition, the C/GaSe0.5S0.5/C device exhibited an ON/OFF switching property from low injection OFF to high injection ON at specific biasing voltages. This voltage decreased with the increasing illumination intensity. On the other hand, the C-V characteristics of the device, which was recorded for an ac input signal with 100 MHz at different levels of photoexcitation shifted up when the intensity of light was increased. When the same measurement was repeated at signal frequency of 1.6 GHz, the C-V characteristics reflected a different level of capacitance response. These features of C/GaSe0.5S0.5/C photodetectors nominate the device to be used as multipurpose optical switches being suitable to store different levels of electromagnetic energy at microwave frequencies.Article Citation Count: 10Analysis of the strong D2* (2460)0 → D+ π- and Ds2*(2573)+ → D+ K0 transitions via QCD sum rules(Springer, 2014) Saraç Oymak, Yasemin; Sarac, Y.; Sundu, H.; Physics GroupThe strong D-2* (2460)(0) -> D+ pi(-) and D-s2* (2573)(+) -> D+ K-0 transitions are analyzed via three-point QCD sum rules. First we calculate the corresponding strong coupling constants g(D2)*D pi and g(Ds2)*DK. Then we use them to calculate the corresponding decay widths and branching ratios. Making use of the existing experimental data on the ratio of the decay width in the pseudoscalar D channel to that of the vector D* channel, finally, we estimate the decay width and branching ratio of the strong D-2(*) (2460)(0) -> D*(2010)(+)pi(-) transition.Article Citation Count: 16ANALYTICAL SOLUTIONS TO VARIABLE THICKNESS AND VARIABLE MATERIAL PROPERTY ROTATING DISKS FOR A NEW THREE-PARAMETER VARIATION FUNCTION(Taylor & Francis inc, 2012) Argeşo, Ahmet Hakan; Manufacturing EngineeringAnalytical solutions of two different annular rotating disk problems are obtained under the assumptions of plane stress, isotropy, and small deformations. The first problem involves a homogeneous variable profile disk, whereas the second one is a functionally graded disk having a variation in elasticity modulus. For the variations of disk thickness and elasticity modulus in these problems, a new form of nonlinear function controlled by three parameters is introduced. The derivations of the closed form solutions for both type of rotating disk problems are carried out in a unified form. The closed form solutions are verified numerically by the nonlinear shooting method.Article Citation Count: 14Analyzing the role of constraints and motivations behind traveling in the prediction of destination choice: Evidence from PLS-SEM and fsQCA(Wiley, 2021) Küçükergin, Kemal Gürkan; Caliskan, Caner; Dedeoglu, Bekir Bora; Birinci, Muhammet Cenk; Tourism ManagementThis study aims to examine the relationship among travel constraints, travel motivations, and destination choice via a multi-method approach. For this purpose, two studies and two analysis tools-PLS-SEM and fsQCA-were employed to conduct examinations in the context of two different target destinations (France and China). Findings revealed that travel constraints and travel motivations generally influenced destination choice. However, it was found that PLS-SEM and fsQCA results were not compatible for some relationships. In light of this and further findings, it was observed that the matter of destination choice is complex by nature.Article Citation Count: 6Anatomy of a failed IMF program -: The 1999 program in Turkey(M E Sharpe inc, 2004) Çapoglu, GThis paper analyzes the failed IMF program in Turkey that was initiated in December 1999. The 1999 Turkish exchange rate-based stabilization program was presented as an improved version of earlier programs implemented in Latin American countries. The inclusion of an exit strategy was considered as an innovative element of the Turkish program. However the program crashed fourteen months after its initiation. This paper argues that the Turkish program underestimated the possible negative impact of unfavorable initial conditions, especially conditions of an institutional nature, which turned out to be a fatal mistake. Among the conditions that were ignored by the 1999 program were the absence of an independent and effective regulatory agency in the banking sector and the circumstances under which the Treasury carried out its borrowing.Review Citation Count: 6Anatomy of a failed IMF program: The 1999 program in Turkey(M.E. Sharpe Inc., 2004) Çapoǧlu,G.This paper analyzes the failed IMF program in Turkey that was initiated in December 1999. The 1999 Turkish exchange rate-based stabilization program was presented as an improved version of earlier programs implemented in Latin American countries. The inclusion of an exit strategy was considered as an innovative element of the Turkish program. However, the program crashed fourteen months after its initiation. This paper argues that the Turkish program underestimated the possible negative impact of unfavorable initial conditions, especially conditions of an institutional nature, which turned out to be a fatal mistake. Among the conditions that were ignored by the 1999 program were the absence of an independent and effective regulatory agency in the banking sector and the circumstances under which the Treasury carried out its borrowing.Article Citation Count: 0Anticipatory effect of execution on observation: an approach using ExoPinch finger robot(Tubitak Scientific & Technological Research Council Turkey, 2019) Arıkan, Kutluk Bilge; Zadeh, Hassan Gol Mohammad; Turgut, Ali Emre; Zinnuroğlu, Murat; Bayer, Gözde; Günendi, Zafer; Cengiz, Bülent; Department of Mechatronics EngineeringBackground/aim: This study aims to explore the mirror neuron system (MNS) involvement using mu (8–12 Hz)/beta (15–25 Hz) bandsuppression in an action observation-execution paradigm.Materials and methods: Electrophysiological (EEG) data from 16 electrodes were recorded while 8 participants observed video clips ofa hand squeezing a spring. Specifically, the effect of anticipated execution on observation was studied. For this purpose, a fully actuatedfinger exoskeleton robot was utilized to synchronize observation and execution and to control the execution condition for the participants. Anticipatory effect was created with a randomized robot accompany session.Results: The results showed that the observational condition (with or without anticipation) interacted with hemisphere at central channels near somatosensory cortex. Additionally, we explored the response of MNS on the kinetics features of visual stimuli (hard or softspring).Conclusion: The results showed an interaction effect of kinetics features and hemisphere at frontal channels corresponding nearly tothe ventral premotor cortex area of the brain. The activation of mirror neurons in this area plays a crucial role in observational learning.Based on our results, we propose that specific type of visual stimuli can be combined with the functional abilities of the MNS in the action observation based treatment of hand motor dysfunction of stroke patients to have a positive additional impact.Article Citation Count: 12Antisolvent-fumigated grain growth of active layer for efficient perovskite solar cells(Pergamon-elsevier Science Ltd, 2021) Park, Jongee; Khan, Suliman; Khan, Ayub; Khan, Danish; Issakhov, Alibek; Park, Jongee; Metallurgical and Materials EngineeringHigh efficiency of perovskite solar cell can be obtained through various approaches, including materials and interface engineering, device modification and fabrication techniques. In all approaches, the quality of the perovskite layer has a significant impact on the efficiency of the perovskite solar cell. Antisolvent dripping is widely used in almost all fabrication methodologies to achieve a high-quality perovskite layer. However, in the conventional antisolvent dripping, there are several factors (antisolvent volume, time and point of dripping, etc.) to be strictly followed. Due to these difficult and critical tricks, researchers often get perovskite layers with pinholes, small grains, and wide grain boundaries that deteriorate the performance of the perovskite solar cells. In order to produce perovskite films with large-scale grains, narrow boundaries and smooth surface morphology, a sealed antisolvent-fumigated process is implemented. There is no need to make any substantial efforts to achieve optimal conditions for the fabrication of high-quality perovskite layers using the antisolvent-fumigated strategy. Consequently, the efficiency of perovskite solar cell improves dramatically from 18.65% to 21.45%. Our findings present a new and convenient method for fabricating highly efficient perovskite solar cells.Article Citation Count: 9The approximation of logarithmic function by q-Bernstein polynomials in the case q > 1(Springer, 2007) Ostrovska, Sofiya; MathematicsSince in the case q > 1, q-Bernstein polynomials are not positive linear operators on C[ 0, 1], the study of their approximation properties is essentially more difficult than that for 0 < q < 1. Despite the intensive research conducted in the area lately, the problem of describing the class of functions in C[ 0, 1] uniformly approximated by their q-Bernstein polynomials ( q > 1) remains open. It is known that the approximation occurs for functions admitting an analytic continuation into a disc {z : | z| < R}, R > 1. For functions without such an assumption, no general results on approximation are available. In this paper, it is shown that the function f ( x) = ln( x + a), a > 0, is uniformly approximated by its q-Bernstein polynomials ( q > 1) on the interval [ 0, 1] if and only if a >= 1.Article Citation Count: 0Aptamer-based magnetic isolation and specific detection system for Listeria monocytogenes from food samples(Elsevier, 2024) Özalp, Veli Cengiz; Ozalp, Veli Cengiz; Arica, Mehmet Yakup; Basic SciencesIn this work, an aptamer-based magnetic system was designed for specific and rapid detection of Listeria monocytogenes in food samples. To prepare the selective magnetic system against the target bacterium, firstly, magnetic particles (Fe3O4) were coated with two hydrophilic polymer layers. The specific aptamer immobilized magnetic system efficiently captured L. monocytogenes cells in a competitive response time of approximately 10 min. The magnetic aptamer detection system was very specific to L. monocytogenes and had high selective, up to 97.6 % compared to the Listeria species (Listeria ivanovii, Listeria innocua, and Listeria seeligeri) and other bacteria species Escherichia coli, Staphylococcus aureus, and Basillus subtilus. The isolation and detection of L. monocytogenes from food samples using the presented method are fast and reliable. Moreover, another significant factor to be contemplated is the use of a few chemicals for detection, reducing the cost of analysis, and the results can be obtained within 18 h.Article Citation Count: 15Are emotions contagious? Developing a destination social servicescape model(Elsevier, 2019) Küçükergin, Kemal Gürkan; Uygur, Selma Meydan; Tourism Management[No Abstract Available]Article Citation Count: 1Are Gender-Neutral Pronouns Really Neutral? Testing a Male Bias in the Grammatical Genderless Languages Turkish and Finnish(Sage Publications inc, 2023) Akbaş Uslu, Gülçin; Lindqvist, Anna; Akbas, Gulcin; Hekanaho, Laura; Senden, Marie Gustafsson; Department of PsychologyLanguages differ in how grammatically salient gender is. We explored if grammatically gender-neutral pronouns in Finnish and Turkish, two grammatically genderless languages, are gender neutral or male biased, thereby activating male, rather than female, exemplars. We also tested whether differences in national level gender equality influence the male bias. Results indicated a male bias in both languages, whereas national level gender equality had no influence. Implications for gender-fair language reforms in grammatically genderless languages are discussed.Article Citation Count: 38Assessment of Features and Classifiers for Bluetooth RF Fingerprinting(Ieee-inst Electrical Electronics Engineers inc, 2019) Uzundurukan, Emre; Kara, Ali; Kara, Ali; Department of Electrical & Electronics Engineering; Airframe and Powerplant MaintenanceRecently, network security has become a major challenge in communication networks. Most wireless networks are exposed to some penetrative attacks such as signal interception, spoofing, and stray. Radio frequency (RF) fingerprinting is considered to be a promising solution for network security problems and has been applied with various improvements. In this paper, extensive data from Bluetooth (BT) devices are utilized in RF fingerprinting implementation. Hilbert-Huang transform (HHT) has been used, for the first time, for RF fingerprinting of Bluetooth (BT) device identification. In this way, time-frequency-energy distributions (TFED) are utilized. By means of the signals' energy envelopes, the transient signals are detected with some improvements. Thirteen features are extracted from the signals' transients along with their TFEDs. The extracted features are pre-processed to evaluate their usability. The implementation of three different classifiers to the extracted features is provided for the first time in this paper. A comparative analysis based on the receiver operating characteristics (ROC) curves, the associated areas under curves (AUC), and confusion matrix are obtained to visualize the performance of the applied classifiers. In doing this, different levels of signal to noise ratio (SNR) levels are used to evaluate the robustness of the extracted features and the classifier performances. The classification performance demonstrates the feasibility of the method. The results of this paper may help readers assess the usability of RF fingerprinting for BT signals at the physical layer security of wireless networks.