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Now showing 1 - 10 of 347
  • Article
    Citation - WoS: 4
    Citation - Scopus: 5
    Stability of Discrete-Time Systems Joined With a Saturation Operator on the State-Space: Yet Another Version of Liu-michel's Criterion
    (Elsevier Gmbh, 2012) Singh, Vimal
    A novel criterion for the global asymptotic stability of fixed-point state-space digital filters using saturation arithmetic is presented. The criterion, which is basically a new version of an earlier criterion due to Liu and Michel, is a generalization and improvement over a recently reported criterion. The generalization is due to the fact that the use of even unsymmetric Lyapunov matrix P is permitted. An example illustrating the improvement realized from the present criterion is given. (C) 2011 Elsevier GmbH. All rights reserved.
  • Review
    Citation - WoS: 64
    Citation - Scopus: 75
    Atmospheric Pressure Plasma Surface Treatment of Polymers and Influence on Cell Cultivation
    (Mdpi, 2021) Sasmazel, Hilal Turkoglu; Alazzawi, Marwa; Alsahib, Nabeel Kadim Abid
    Atmospheric plasma treatment is an effective and economical surface treatment technique. The main advantage of this technique is that the bulk properties of the material remain unchanged while the surface properties and biocompatibility are enhanced. Polymers are used in many biomedical applications; such as implants, because of their variable bulk properties. On the other hand, their surface properties are inadequate which demands certain surface treatments including atmospheric pressure plasma treatment. In biomedical applications, surface treatment is important to promote good cell adhesion, proliferation, and growth. This article aim is to give an overview of different atmospheric pressure plasma treatments of polymer surface, and their influence on cell-material interaction with different cell lines.
  • Article
    Citation - WoS: 10
    Citation - Scopus: 10
    Temperature Effects on Optical Characteristics of Cdse Thin Films
    (Elsevier Sci Ltd, 2021) Gullu, H. H.; Isik, M.; Surucu, O.; Gasanly, N. M.; Parlak, M.
    CdSe is one of the significant members of II-VI type semiconducting family and it has a wide range of technological applications in which optoelectronic devices take a special position. The present paper reports the structural and optical characteristics of thermally evaporated CdSe thin films. XRD pattern exhibited preferential orientation along (111) plane while atomic composition analyses resulted in the ratio of Cd/Se as closer to 1.0. Temperature-dependent band gap characteristics of CdSe thin films were investigated for the first time by carrying out transmission experiments in the 10-300 K range. The analyses showed that direct band gap energy of the compound decreases from 1.750 (at 10 K) to 1.705 eV (at 300 K). Varshni model was successfully applied to the temperature-band gap energy dependency and various optical constants were determined. Raman spectrum of CdSe thin films was also presented to understand the vibrational characteristics of the compound. The present paper would provide worthwhile data to researchers especially studying on optoelectronic device applications of CdSe thin films.
  • Article
    Citation - WoS: 7
    Citation - Scopus: 8
    Rock mass response model for circular openings
    (Canadian Science Publishing, 2007) Sari, Dursun
    The main parameters affecting the failure and deformation state of the rock mass around a circular opening are the level of vertical and horizontal in situ stresses, the characteristics of the rock mass, the diameter of the opening, and the support pressure. The influence of all these parameters on the stress-induced final deformations around circular openings was investigated by a finite difference based two-dimensional numerical simulation for both hydrostatic and nonhydrostatic stress field conditions. From the results of the parametric studies, the variation of tunnel strain versus the ratio of uniaxial compressive strength of the rock mass to in situ vertical stress and the ratio of radial support pressure to in situ vertical stress for fair quality and poor quality rock masses was statistically analysed. As a result of the three-dimensional nonlinear regression analysis and surface curve fitting process by means of a large number of models, a best-fit model with the best correlation with these dimensionless parameters was proposed for calculating tunnel strains and ground response curves. Specific charts were created to highlight the influence of parameters on the deformation response of the openings to various support pressures.
  • Article
    Citation - WoS: 5
    Citation - Scopus: 6
    On the Design and Effectiveness of Simulink-Based Educational Material for a Communication Systems Course
    (Wiley, 2020) Coruk, R. Busra; Yalcinkaya, Bengisu; Kara, Ali
    The methods used in engineering education have gained diversity in parallel with rapidly evolving technology. New technological methods along with the traditional methods have been adopted for undergraduate education. Today, Simulink-based educational materials are used in many fields in engineering education. However, in the literature, the contribution of such educational materials to the learning process has not been measured thoroughly. This study presents a comprehensive measurement method to improve the created course material and show the effectiveness of developed course material in students' success. First, educational material was developed for an undergraduate electrical engineering course: communication systems. A feedback group made up of diverse student learners was employed extensively in the material development phase. Next, the impact of the developed material on the success of the students was examined using both qualitative and quantitative measurement tools including questionnaires, one-to-one interviews, and class and university level anonymous surveys. This also included students' performance regarding laboratory quizzes and achievement of course learning outcomes. Overall, the measurement results show that the course material increased students' success in the course. Moreover, students' general perception of the course material was positive.
  • Article
    Citation - WoS: 9
    Citation - Scopus: 9
    Optical Dynamics in the Ag/Α-ga2< Layer System
    (Elsevier Sci Ltd, 2018) Alharbi, S. R.; Qasrawi, A. F.
    In this work, thin films of Ga2S3 are deposited onto 150 nm thick transparent Ag substrate by the physical vapor deposition technique under vacuum pressure of 10(-5) mbar. The films are studied by the X-ray diffraction and optical spectrophotometry techniques. It is found that the Ag substrate induced the formation of the monoclinic alpha-Ga2S3 polycrystals. The transparent Ag substrate also changed the preferred optical transition in Ga2S3 from direct to indirect It also increased the light absorption by 79 and 23 times at incident light energies of 2.01 and 2.48 eV, respectively. In addition, a red shift in all types of optical transitions is observed. Some the extended energy band tails of Ag appears to form interbands in the band gap of Ga2S3. These interbands strongly attenuated the dielectric and optical conduction parameters. Particularly, an enhancement in the dielectric constant values and response to incident electromagnetic field is observed. The Drude-Lorentz modeling of this interface has shown that the free carrier density, drift mobility, plasmon frequency and reduced electron-plasmon frequency in Ga2S3 increases when the Ag substrate replaced the glass or other metals like Yb, Al and Au. The nonlinear optical dynamics of the Ag/Ga2S3 are promising as they indicate the applicability of this interface for optoelectronic applications.
  • Article
    Citation - WoS: 30
    Citation - Scopus: 48
    A Fusion-Based Framework for Wireless Multimedia Sensor Networks in Surveillance Applications
    (Ieee-inst Electrical Electronics Engineers inc, 2019) Yazici, Adnan; Koyuncu, Murat; Sert, Seyyit Alper; Yilmaz, Turgay
    Multimedia sensors enable monitoring applications to obtain more accurate and detailed information. However, the development of efficient and lightweight solutions for managing data traffic over wireless multimedia sensor networks (WMSNs) has become vital because of the excessive volume of data produced by multimedia sensors. As part of this motivation, this paper proposes a fusion-based WMSN framework that reduces the amount of data to be transmitted over the network by intra-node processing. This framework explores three main issues: 1) the design of a wireless multimedia sensor (WMS) node to detect objects using machine learning techniques; 2) a method for increasing the accuracy while reducing the amount of information transmitted by the WMS nodes to the base station, and; 3) a new cluster-based routing algorithm for the WMSNs that consumes less power than the currently used algorithms. In this context, a WMS node is designed and implemented using commercially available components. In order to reduce the amount of information to be transmitted to the base station and thereby extend the lifetime of a WMSN, a method for detecting and classifying objects on three different layers has been developed. A new energy-efficient cluster-based routing algorithm is developed to transfer the collected information/data to the sink. The proposed framework and the cluster-based routing algorithm are applied to our WMS nodes and tested experimentally. The results of the experiments clearly demonstrate the feasibility of the proposed WMSN architecture in the real-world surveillance applications.
  • Conference Object
    Aldose Reductase Natural Inhibitors From Ethyl Acetate Extracts From Southern Turkey
    (Taylor & Francis inc, 2010) Onay, Melih; Coruh, Nursen; Isgor, Belgin
    [No Abstract Available]
  • Article
    Mobile Payment Adoption During the COVID-19 Pandemic: A Systematic Literature Review
    (Palgrave Macmillan Ltd, 2026) Belbag, Aybegum Gungordu; Güngördü Belbağ, Aybegüm
    During the pandemic, the shift to non-physical transactions increased the need for mobile payments. This study aims to offer a systematic literature review on consumer behavior towards mobile payment during the pandemic, using the Theory, Context, Characteristics, and Methodology framework and following the Scientific Procedures and Reasons for Systematic Literature Reviews protocol. 47 articles from the WOS database were analyzed, revealing a dominance of quantitative studies, primarily based on the Technology Acceptance Model and UTAUT. Findings show that environmental stimuli and internal states (organism) shape behaviors and behavioral intentions (responses) towards mobile payments during the pandemic. The study concludes with future research directions grounded in the TCCM framework.
  • Article
    Citation - WoS: 45
    Citation - Scopus: 45
    A Note on "some Results on Multi-Valued Weakly Jungck Mappings in b-metric Space"
    (versita, 2013) Bota, Monica-Felicia; Karapinar, Erdal
    The proofs of Theorems 2.1, 2.2 and 2.3 from [Olatinwo M.O., Some results on multi-valued weakly jungck mappings in b-metric space, Cent. Eur. J. Math., 2008, 6(4), 610-621] base on faulty evaluations. We give here correct but weaker versions of these theorems.