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Article Citation - WoS: 8Citation - Scopus: 8Berinde Mappings in Ordered Metric Spaces(Springer-verlag Italia Srl, 2015) Karapinar, Erdal; Sadarangani, KishinRecently, Samet and Vetro proved a fixed point theorem for mappings satisfying a general contractive condition of integral type in orbitally complete metric spaces (Samet and Vetro, Chaos Solitons Fractals 44:1075-1079, 2011). Our aim in this paper is to present a version of the results obtained in the above mentioned paper in the context of ordered metric spaces. Some examples are presented to distinguish our results from the existing ones.Article Citation - WoS: 6Citation - Scopus: 6Physical Properties of the Bi1.5zn0.92-2x< Solid Solutions(Elsevier Sci Ltd, 2016) Al Garni, S. E.; Qasrawi, A. F.; Mergen, A.The Hf doping effect on the structural, compositional, optical, electrical and dielectric properties of the bismuth-zinc-niobium oxide pyrochlore ceramics is explored by means of scanning electron microscopy, energy dispersive X-ray spectroscopy, ultraviolet-visible light spectroscopy in the wavelength range of 200-1100 nm, temperature dependent electrical resistivity measurements in the range of 300-460 K and dielectric spectroscopy in the frequency range of 0.1-1.0 GHz. The optimum solubility limit in the Bi1.5Zn0.92-2xHfxNb1.5O6.92 solid solution is observed for the Hf content of 0.06. Increasing the Hf content from 0.03 to 0.06 decreased the room temperature, lattice constant, strain, dislocation density, optical energy band gap and electrical resistivity. It also increased the crystallite size and the dielectric constant. The energy band gap of the pure BZN (3.30 eV) decreased to 2.21 and reached 2.10 eV as the Hf content increased from 0.03 to 0.06. This behavior of the BZN suggests its suitability for optical applications of the visible region of light like photovoltaic devices. In addition, the remarkable increase in the dielectric constant from 258 to 280 and 456 nominates the Hf doped pyrochlore for passive mode operation devices like microwave capacitors. (C) 2015 Elsevier Ltd and Techna Group S.r.l. All rights reserved.Conference Object Citation - WoS: 1A Platinum-Blue Complex Exerts Its Cytotoxic Activity Via Dna Damage and Induces Apoptosis in Cancer Cells(Elsevier Sci Ltd, 2016) Adiguzel, Z.; Ozalp-Yaman, S.; Celik, G.; Salem, S.; Bagci-Onder, T.; Cetin, Y. C.; Acilan, C.[No Abstract Available]Article Citation - WoS: 13Citation - Scopus: 13Numerical Solution of Buoyancy Mhd Flow With Magnetic Potential(Pergamon-elsevier Science Ltd, 2014) Pekmen, B.; Tezer-Sezgin, M.In this study, dual reciprocity boundary element method (DRBEM) is applied for solving the unsteady flow of a viscous, incompressible, electrically conducting fluid in channels under the effect of an externally applied magnetic field and buoyancy force. Magnetohydrodynamics (MHD) equations are coupled with the energy equation due to the heat transfer by means of the Boussinessq approximation. Then, the 20 non-dimensional full MHD equations in terms of stream function, temperature, magnetic potential, current density and vorticity are solved by using DRBEM with implicit backward Euler time integration scheme. Numerical results are obtained utilizing linear boundary elements and linear radial basis functions approximation for the inhomogeneities, in a double lid-driven staggered cavity and in a channel with backward facing step. The results are given for several values of problem parameters as Reynolds number (Re), magnetic Reynolds number (Rem), Hartmann number (Ha) and Rayleigh number (Ra). With the increase in Rem, both magnetic potential and current density circulate near the abrupt changes of the walls. The increase in Ha suppresses this perturbation, and forces the magnetic potential lines to be in the direction of the applied magnetic field. The boundary layer formation through the walls emerge in the flow and current density for larger values of Ha. (C) 2013 Elsevier Ltd. All rights reserved.Editorial Citation - WoS: 4Citation - Scopus: 5Discussion of "bearing Capacity of Geocell Reinforcement in Embankment Engineering" by Ling Zhang, Minghua Zhao, Caijun Shi and Heng Zhao 2010,28; 475-482(Elsevier Sci Ltd, 2012) Gurbuz, Ayhan[No Abstract Available]Article Citation - WoS: 23Citation - Scopus: 26Optimization Problems for a Parallel System With Multiple Types of Dependent Components(Elsevier Sci Ltd, 2020) Eryilmaz, Serkan; Ozkut, MuratThis paper is concerned with two optimization problems for a parallel system that consists of dependent components. First, the problem of finding the number of elements in the system that minimizes the mean cost rate of the system is considered. The second problem is concerned with the optimal replacement time of the system. Previous work assumes that the components are independent. We discuss the impact of dropping this assumption. In particular, we numerically examine how the dependence between the components affects the optimal number of units and replacement time for the system which minimize mean cost rates. We first consider the case when the components are exchangeable and dependent, i.e. the system consists of single type of dependent components. Subsequently, we consider a system that consists of multiple types of dependent components. Comparative numerical results are presented for particularly chosen dependence models.Article Citation - WoS: 4Citation - Scopus: 6Surgical Outcomes of Posterior Persistent Fetal Vasculature Syndrome: Cases With Tent-Shaped and Closed Funnel-Shaped Retinal Detachment(Springernature, 2023) Zeydanli, Ece Ozdemir; Ozdek, Sengul; Acar, Burak; Ozdemir, Huseyin Baran; Aktas, Zeynep; Gurelik, Gokhan; Atalay, Hatice Tuba; Ozdemir Zeydanli, EceBackground/objectives To determine the role of vitreoretinal surgery (VRS) for two different forms of posterior persistent fetal vasculature syndrome (PFVS); with tent-shaped tractional retinal detachment (TRD) and closed funnel-shaped TRD. Subjects/methods Retrospective, single surgeon, consecutive case series of 52 eyes of 44 patients with posterior PFVS who underwent VRS. Cases were divided into "tent-shaped TRD" and "funnel-shaped TRD" groups based on the preoperative TRD configuration. Associated anomalies, functional and anatomical outcomes were evaluated. The cosmetic appearance was defined as poor if there was phthisis bulbi, gross buphthalmos, or corneal opacification; acceptable if there was apparent leukocoria; and excellent if none were noted at the last follow-up. Results Thirty eyes of 29 patients presented with tent-shaped TRD; 70% of which obtained counting fingers or better vision and 90% showed significant reversal of tenting achieving retinal reattachment. The cosmetic appearance was excellent in 87%. Two eyes (7%) became phthisic. Twenty-two eyes of 15 patients presented with funnel-shaped TRD and leukocoria; 45% achieved LP vision and 70% of patients with bilateral pathology had LP in at least one eye. The cosmetic appearance was acceptable to excellent in 73%. Three eyes (14%) became phthisic, one (5%) of which required enucleation. The median follow-up time was 16 (6-71) months. Conclusions VRS often provides functional vision and anatomy in posterior PFVS with tent-shaped TRD morphology. In the funnel-shaped TRD morphology, where no treatment has historically been recommended, surgery may be considered with an aim of restoring light perception and globe preservation, particularly in bilateral cases.Article Citation - WoS: 55Citation - Scopus: 61Encoding the Future: Successful Processing of Intentions Engages Predictive Brain Networks(Academic Press inc Elsevier Science, 2010) Poppenk, J.; Moscovitch, M.; McIntosh, A. R.; Ozcelik, E.; Craik, F. I. M.Evidence from cognitive, patient and neuroimaging research indicates that "remembering to remember" intentions, i.e., prospective memory (PM) retrieval, requires both general memory systems involving the medial temporal lobes and an executive system involving rostral PFC (BA 10). However, it is not known how prospective memories are initially formed. Using fMRI, we investigated whether brain activity during encoding Of future intentions and present actions differentially predicted later memory for those same intentions (PM) and actions (retrospective memory). We identified two significant patterns of neural activity: a network linked to overall memory and another linked specifically to PM. While overall memory success was predicted by temporal lobe activations that included the hippocampus, PM success was also uniquely predicted by activations in additional regions, including left rostrolateral PFC and the right parahippocampal gyrus. This finding extends the role of these structures to the formation of individual intentions. It also provides the first evidence that PM encoding, like PM retrieval, is supported by both a common episodic memory network and an executive network specifically recruited by future-oriented processing. (C) 2009 Elsevier Inc. All rights reserved.Article Citation - WoS: 19Citation - Scopus: 21Mean Instantaneous Performance of a System With Weighted Components That Have Arbitrarily Distributed Lifetimes(Elsevier Sci Ltd, 2013) Eryilmaz, SerkanThere are various systems consisting of components which may have different contribution to the performance of the system. Such systems can be modeled systems with weighted components. In this paper, we study the mean instantaneous performance of this type of systems after successive component failures. The mean instantaneous performance is a useful characteristic to take preventive action about the system. In particular, we obtain explicit expressions for the mean instantaneous performance of a system with weighted components that have arbitrarily distributed lifetimes. We illustrate the results when the lifetime distribution of components follow proportional hazard model. Some further results are also presented for the components having exponential lifetime distribution. (C) 2013 Elsevier Ltd. All rights reserved.Article Citation - WoS: 6Citation - Scopus: 7Parallel and Consecutive-k-out-of-n< Systems Under Stochastic Deterioration(Elsevier Science inc, 2014) Eryilmaz, SerkanIn this paper, we study parallel and consecutive-k-out-of-n:F systems consisting of components which are subject to random deterioration with time. The random deterioration in resistance of a component is defined through a stochastic process. We obtain lifetime distribution of a parallel system via classical probabilistic techniques. The lifetime distribution of a consecutive-k-out-of-n:F system is derived using the lifetime distribution of parallel systems and the concept of maximal signature. We also study the optimal replacement time for a parallel system. We present illustrative computational results using MATHCAD. (C) 2013 Elsevier Inc. All rights reserved.
