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Article Citation - WoS: 4An Eye-Controlled Wearable Communication and Control System for Als Patients: Smarteyes(Yildiz Technical Univ, 2017) Sumer, Emre; Uslu, I. Baran; Turker, MustafaALS (Amyotrophic Lateral Sclerosis) is a progressive neurodegenerative disease that involves the malfunctioning of motor neurons. The ability of the brain to initiate and control muscle movement is lost subsequent to death of motor neurons. People with ALS present the greatest challenge regarding communication issues. Besides, caring for a loved one with ALS is not an easy task. In this study, we developed an eye-controlled wearable system called "SmartEyes" which improves the life qualities of ALS patients and their caregivers by offering two important skills. The first skill is communicating through predefined voice messages generated by a computer and the second one is controlling several peripherals located in the patient's environment. The developed system is novel in that; the patients can easily vocalize their needs and requests with a few sequential eye movements. Moreover, they can control several household items including desk lamp, rolling curtain, television and air conditioner in the same way. The preliminary experiments showed that the performance of the system is satisfactory. The accuracy of the system commands based on pupil gaze direction was tested on several users and about an accuracy of 89% was achieved. It is believed that the developed system has attracted the patients' and their caregivers' interest very much and this is the main motivation in improving our system.Article Citation - WoS: 22Citation - Scopus: 32Organizational Issues in Embracing Agile Methods: an Empirical Assessment(Springer india, 2021) Mishra, Alok; Abdalhamid, Samia; Mishra, Deepti; Ostrovska, SofiyaThis study provides empirical evidence to the body of knowledge in Agile methods adoption in small, medium and large organizations in international context. This research explores the factors involved in the adoption of Agile methods in software development organizations. A survey was conducted among Agile professionals to gather survey data from 52 software organizations in seven countries across the world. Statistical techniques are applied towards empirical assessment. Organizational culture, team structure and management support are found to be crucial success factors whereas lack of management support, a large organization size and traditional organizational culture are found to be detrimental for the adoption of Agile approach in an organization. The selection of an appropriate Agile method depends on the project size and, for each size, there are specific methods preferred by different enterprises. Providing better control over the work is viewed as the primary advantage of the Agile methods within large and small organizations, while for the medium-size organizations, the priority is switched to coping with changing user requirements. Majority of the respondents did not consider embracing agile methods as a reason for project failure which indicates that Agile methods are, indeed, beneficial.Article Citation - WoS: 9Citation - Scopus: 12Some Integral Type Common Fixed Point Theorems Satisfying Φ-Contractive Conditions(Belgian Mathematical Soc Triomphe, 2014) Chauhan, Sunny; Karapinar, ErdalIn this manuscript, we obtain some common fixed point results of two pairs having the common limit range property in the setting of integral type contraction in the framework of symmetric (semi-metric) spaces. Moreover, we extend our results from two pairs of self-mappings to four finite families of self mappings to get common fixed points. Our results improve and extend a host of previously known results. Further, we establish some illustrative examples to show the validity of the main results.Article Citation - WoS: 7Citation - Scopus: 7A New Strategy for Solving Store Separation Problems Using Openfoam(Sage Publications Ltd, 2022) Abuhanieh, Saleh; Akay, Hasan U.; Bicer, BarisThe ability of OpenFOAM to solve the problem of a store separating from an air vehicle (store separation problem) has been evaluated using a dynamic mesh (Overset/Chimera) technique for an industry-class (transonic and generic) benchmark test case. The major limitations of the standard libraries have been determined. To tackle these challenges, a new strategy has been proposed and implemented using only open-source libraries and tools. The strategy combines porting, modifying, and adapting an overset library from the OpenFOAM fork platform (foam-extend) to the standard OpenFOAM platform (ESI). Furthermore, in order to overcome the well-known weakness of the standard OpenFOAM compressible solvers, the newly adapted overset library was integrated with an open-source, density-based, and coupled solver (HiSA), which uses the OpenFOAM technology. Additionally, a force restrained model was developed to consider the externally applied forces on the store by the store ejectors. The accuracy of the developed strategy has been compared with wind tunnel tests and the solutions of two well-known commercial codes, showing good agreements with them. While the study has focused on simulations with inviscid Euler equations (typical of the test case considered here), the viscosity effect on the solution has also been studied with Navier-Stokes equations and compared with other results in the literature, showing minor differences. To the best of the authors' knowledge, this is the first work which studies and validates the store separation problem in transonic regime with OpenFOAM.Article On the Moment-Determinacy of Power Lindley Distribution and Some Applications To Software Metrics(Acad Brasileira de Ciencias, 2021) Khalleefah, Mohammed; Ostrovska, Sofiya; Turan, MehmetThe Lindley distribution and its numerous generalizations are widely used in statistical and engineering practice. Recently, a power transformation of Lindley distribution, called the power Lindley distribution, has been introduced by M. E. Ghitany et at who initiated the investigation of its properties and possible applications. In this article, new results on the power Lindley distribution are presented. The focus of this work is on the moment-(in)determinacy of the distribution for various values of the parameters. Afterwards, certain applications are provided to describe data sets of software metrics.Article Citation - WoS: 32Citation - Scopus: 39A Computationally Efficient Method for Hybrid Eeg-Fnirs Bci Based on the Pearson Correlation(Hindawi Ltd, 2020) Hasan, Mustafa A. H.; Khan, Muhammad U.; Mishra, DeeptiA hybrid brain computer interface (BCI) system considered here is a combination of electroencephalography (EEG) and functional near-infrared spectroscopy (fNIRS). EEG-fNIRS signals are simultaneously recorded to achieve high motor imagery task classification. This integration helps to achieve better system performance, but at the cost of an increase in system complexity and computational time. In hybrid BCI studies, channel selection is recognized as the key element that directly affects the system's performance. In this paper, we propose a novel channel selection approach using the Pearson product-moment correlation coefficient, where only highly correlated channels are selected from each hemisphere. Then, four different statistical features are extracted, and their different combinations are used for the classification through KNN and Tree classifiers. As far as we know, there is no report available that explored the Pearson product-moment correlation coefficient for hybrid EEG-fNIRS BCI channel selection. The results demonstrate that our hybrid system significantly reduces computational burden while achieving a classification accuracy with high reliability comparable to the existing literature.Article Citation - WoS: 19Citation - Scopus: 19Temperature-Dependent Band Gap Characteristics of Bi12sio20< Single Crystals(Amer inst Physics, 2019) Isik, M.; Delice, S.; Gasanly, N. M.; Darvishov, N. H.; Bagiev, V. E.Bi12SiO20 single crystals have attracted interest due to their remarkable photorefractive characteristics. Since bandgap and refractive index are related theoretically to each other, it takes much attention to investigate temperature dependency of bandgap energy to understand the behavior of photorefractive crystals. The present study aims at investigating structural and optical characteristics of photorefractive Bi12SiO20 single crystals grown by the Czochralski method. The structural characterization methods indicated that atomic composition ratios of constituent elements were well-matched with the chemical compound Bi12SiO20, and grown crystals have a cubic crystalline structure. Optical properties of crystals were investigated by room temperature Raman spectroscopy and temperature-dependent transmission measurements between 10 and 300 K. The analyses of transmittance spectra by absorption coefficient and derivative spectrophotometry techniques resulted in energy bandgaps decreasing from 2.61 to 2.48 eV and 2.64 to 2.53 eV as temperature was increased from 10 to 300 K. The Varshni model was applied to analyze temperature-bandgap energy dependency.Article Citation - WoS: 5Citation - Scopus: 7Emulating Erasmus? Turkey's Mevlana Exchange Program in Higher Education(Springer Heidelberg, 2019) Yilmaz, GozdeIn today's world, globalization and internationalization of education necessitate new initiatives to catch the new era. Turkey, as a country in between the east and the west, attempts to do so through its recent exchange program in higher education. Interestingly, Turkey's Mevlana exchange program as an ambitious project in higher education denotes an instance of policy transfer: taking the EU model (i.e., Erasmus) and slightly adjusting it to the national circumstances. This article unpacks Turkey's Mevlana program to demonstrate the process of policy transfer by focusing on different questions posed within the policy transfer literature. It argues that Mevlana is drawn from Erasmus, and it is created as a tool of soft power that is increasingly exercised by Turkey due to its changing focus within the Turkish foreign policy of 2000s.Article Citation - WoS: 12Skeletonization-based beam finite element models for stochastic bicontinuous materials: Application to simulations of nanoporous gold(Cambridge Univ Press, 2018) Soyarslan, Celal; Argeso, Hakan; Borgmann, SwantjeAn efficient representative volume element generation strategy is developed in modeling nanoporous materials. It uses periodic 3D beam finite element (FE) models derived from skeletonization of spinodal-like stochastic microstructures produced by a leveled random field. To mimic stiffening with agglomeration of the mass at junctions, an increased Young's modulus is assigned to the elements within the junction zone. The effective Young's modulus, Poisson's ratio, and universal anisotropy index are computed. A good agreement of the Young's modulus predictions with those obtained from experimental results for phase volume fractions 0.20 < phi(B) < 0.50 is observed. Moreover, the elastic anisotropy index of the generated beam networks shows sufficient proximity to isotropy. Finally, it is demonstrated that, as compared to the simulation statistics of voxel-FE models, for the beam-FE models over 500-fold computational acceleration with 250-fold less memory requirement is provided.Article Citation - WoS: 13Citation - Scopus: 13Evaluation of procedural and clinical outcomes of transcatheter aortic valve implantation: A single-center experience(Kare Publ, 2020) Karaduman, Bilge Duran; Kayaoğlu, Hüseyin Ayhan; Keleş, Telat; Bozkurt, EnginObjective: Transcatheter aortic valve implantation (TAVI) is an established alternative to surgical aortic valve replacement. Our study aimed to evaluate the implementation of TAVI at our large-volume center, having an all-comer patient population with short and long-term follow-ups. Methods: This retrospective, single-center analysis included 556 consecutive patients with symptomatic severe aortic stenosis (AS) who underwent TAVI between July 2011 and December 2019. Results: The mean age of the entire population was 77.6±7.9 years, and 54.9% were women. The Society of Thoracic Surgeons (STS) mean score of the cohort was 6.0%±3.5%. The balloon-expandable valve (Sapien XT, Sapien 3; Edwards Lifesciences, Irvine, California) was the most frequently used valves in this cohort (94.6%). Transfemoral access was used in 96.3% of patients. Implantation success was achieved in 96.6% of cases. During the TAVI procedure, 7.2% of patients required permanent pacemaker implantation, with 37.5% in the Lotus valve group needing the most permanent pacemakers. The mean length of hospital stay for the entire cohort was 4.5±2.3 days. Overall, 22 (3.9%) in-hospital deaths occurred before hospital discharge. The mean follow-up period was 15.1±14.9 months for all patients, and a significant improvement was noted in all echocardiographic parameters and functional capacity. Paravalvular leak (PVL) was documented in 18.9% patients, mild in 17.9%, and moderate in 1% at discharge. No cases with severe PVL, necessitating additional procedures. The multiple logistic regression analysis revealed that sex, STS score, baseline SYNTAX score, bicuspid valve morphology, common femoral artery diameter, and post-TAVI PVL were independent predictors of overall mortality. Conclusion: To our knowledge, this study, which is the largest single-center real-world experience of TAVI in Turkey, demonstrated low complication rates with favorable short- and mid-term THV performance in patients undergoing TAVI.
