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Article Citation - WoS: 45Citation - Scopus: 45An Ambipolar Low Band Gap Material Based on Bodipy and Edot(Elsevier Science Bv, 2009) Algi, Fatih; Cihaner, AtillaA novel donor-acceptor type conducting polymer based on BODIPY dye as acceptor and EDOT units as donor parts is synthesized electrochemically. The unique combination of BODIPY and EDOT units provides an ambipolar (n- and p-doping processes) low band gap material (4). This is the first example of p-n junction in an organic pi-conjugated material where BODIPY unit is incorporated directly in the main chain. Furthermore, the polymer film exhibits electrochromic behavior upon p-doping: a color change from light violet (neutral) to indigo (oxidized). (C) 2009 Elsevier B.V. All rights reserved.Article Citation - WoS: 80Citation - Scopus: 85Methylene Blue Photocatalytic Degradation Under Visible Light Irradiation on Copper Phthalocyanine-Sensitized Tio2 Nanopowders(Elsevier Science Bv, 2017) Cabir, Beyza; Yurderi, Mehmet; Caner, Nurdan; Agirtas, Mehmet Salih; Zahmakiran, Mehmet; Kaya, MuratDescribed herein is a new photocatalytic material that shows remarkable catalytic performance in terms of activity and reusability in the photocatalytic degradation of methylene blue (MB) in water. The new catalyst system comprised of copper phthalocyanine modified titanium(IV) oxide (TiO2) nanopowders (CuPc-TiO2\) was prepared by the wet chemical impregnation method to improve the photocatalytic activity of TiO2 and characterized by the combination of various spectroscopic tools including ICP-OES, P-XRD, DR/UV-Vis, FTIR, FE-SEM, SEM-EDX, BFTEM, HRTEM and N-2-adsorption-desorption techniques. The photocatalytic performance of the resulting CuPc-TiO2 in terms of activity and stability was evaluated by the photocatalytic degradation of MB in aqueous solution under mild conditions. Our results revealed that CuPc-TiO2 photocatalyst displayed remarkable activity (TOF = 3.73 mol MB/(mol CuPc + mol TiO2) x h) in the complete (100%) photocatalytic degradation of MB under visible light irradiation (150 W). Moreover, CuPc-TiO2 photocatalyst showed excellent stability against to sintering and clumping throughout the reusability experiments and it retained >80% of its initial activity even at 5th reuse, which makes it reusable photocatalyst in the photocatalytic degradation of MB. (C) 2017 Elsevier B.V. All rights reserved.Article Citation - WoS: 11Citation - Scopus: 13Geometric Distribution of Order k With a Reward(Elsevier Science Bv, 2014) Eryilmaz, SerkanIn this paper, we introduce and study geometric distribution of order k with a reward. In a sequence of binary trials, suppose that each time a success occurs a random reward is received. The distribution of the number of trials until the sum of consecutive rewards is equal to or exceeds the level k is called geometric distribution of order k with a reward. We obtain expressions for the probability mass function of this distribution. (C) 2014 Elsevier B.V. All rights reserved.Article Citation - WoS: 21Citation - Scopus: 24Chaotic Dynamics of Resistively Coupled Dc-Driven Distinct Josephson Junctions and the Effects of Circuit Parameters(Elsevier Science Bv, 2009) Kurt, Erol; Canturk, MehmetTwo distinct Josephson junctions (JJs) connected with a constant coupling resistance R(cp) are theoretically considered to investigate the overall dynamics below and above the critical current I(c). The circuit model of the device is driven by two DC current sources, I(1) and I(2). Each junction is characterized by a nonlinear resistive-capacitive junction (NRCSJ). Having constructed the circuit model, time-dependent simulations are carried out for a variety of control parameter sets. Common techniques such as bifurcation diagrams, two-dimensional attractors and Lyapunov exponents are applied for the determination of chaotic as well as periodic dynamics of the superconducting junction devices. According to the findings, two states (namely superconducting and ordinary conducting) are determined as functions of the source currents. The chaotic current which flows through Rcp exhibits a very rich behavior depending on the source currents I(1) and I(2) and junction capacitances C(1) and C(2). The device characteristics are summarized by a number of three-dimensional phase diagrams in the parameter space. In addition, for certain parameters, hyper-chaotic cases with two positive Lyapunov exponents are encountered. In contrast to earlier studies claiming the need for a sinusoidal feeding current for generating a chaotic signal, our circuitry can easily generate one via a DC source. (C) 2009 Elsevier B.V. All rights reserved.Article Citation - WoS: 3Citation - Scopus: 3q-stieltjes Classes for Some Families of q-densities(Elsevier Science Bv, 2019) Ostrovska, Sofiya; Turan, MehmetThe Stieltjes classes play a significant role in the moment problem allowing to exhibit explicitly infinite families of probability densities with the same sequence of moments. In this paper, the notion of q-moment determinacy/indeterminacy is proposed and some conditions for a distribution to be either q-moment determinate or indeterminate in terms of its q-density have been obtained. Also, a q-analogue of Stieltjes classes is defined for q-distributions and q-Stieltjes classes have been constructed for a family of q-densities of q-moment indeterminate distributions. (C) 2018 Elsevier B.V. All rights reserved.Article Citation - WoS: 6Citation - Scopus: 6Al/Cdse Resonant Tunneling Thin Film Transistors(Elsevier Science Bv, 2017) Qasrawi, A. F.; Kayed, T. S.; Elsayed, Khaled A.An 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.Conference Object Citation - WoS: 15Mobile Technology Applications in the Healthcare Industry for Disease Management and Wellness(Elsevier Science Bv, 2015) Kalem, Guler; Turhan, CigdemTechnology is an unavoidable fact of today's life. Attractive advantages of wireless technology accelerated the rapid development of mobile applications. With the increase of the usage of mobile devices in the recent years, new solutions come to mind including mobile technologies to fulfill requirements or suggest better solutions in the vast area of medical informatics to the existing ones. Augmentation in the area of wireless technology positively affects the medical applications. In the healthcare industry, mobile applications provide better personalized health care, disease management and services to patients and their relatives, as well as a better and flexible way of communicating with physicians, patients and medical suppliers. It is obvious that the applications using mobile technologies has the potential to bring better conditions both for the patients for their disease management and for the humanity for checking their self wellness. In this paper, the current mobile technology utilized in healthcare such as relapse prevention in schizophrenia, aged people's care and wellness, diagnosis and management of attention-deficit etc. is reviewed in detail outlining the current mobile technologies and wireless revolution of today and examining some of the outstanding applications using these technologies in the clinical area. The results of this study can provide clues to researchers to further the mobile technology in healthcare. (C) 2015 The Authors. Published by Elsevier Ltd. This is an open access article under the CC BY-NC-ND license (http://creativecommons.org/licenses/by-nc-nd/4.0/).Article Citation - WoS: 32Citation - Scopus: 32Temperature Dependence of the Band Gap, Refractive Index and Single-Oscillator Parameters of Amorphous Indium Selenide Thin Films(Elsevier Science Bv, 2007) Qasrawi, A. F.InSe thin films are obtained by evaporating InSe crystal onto ultrasonically cleaned glass substrates under pressure of similar to 10(-5) Torr. The structural and compositional analysis revealed that these films are of amorphous nature and are atomically composed of similar to 51% In and similar to 49% Se. The reflectance and transmittance of the films are measured at various temperatures (300-450 K) in the incident photon energy range of 1.1-2.1 eV. The direct allowed transitions band gap - calculated at various temperatures - show a linear dependence on temperature. The absolute zero value band gap and the rate of change of the band gap with temperature are found to be (1.62 +/- 0.01) eV and -(4.27 +/- 0.02) x 10(-4) eV/K, respectively. The room temperature refractive index is estimated from the transmittance spectrum. The later analysis allowed the identification of the static refractive index, static dielectric constant, oscillator strength and oscillator energy. (c) 2006 Elsevier B.V. All rights reserved.Article Citation - WoS: 23Citation - Scopus: 25A Neutral State Yellow To Navy Polymer Electrochrome With Pyrene Scaffold(Elsevier Science Bv, 2011) Icli-Ozkut, Merve; Cihaner, Atilla; Oztas, Zahide; Algi, Fatih; Cihaner, Atilla; Cihaner, Atilla; Içi-Özkut, Merve; Chemical Engineering; Chemical EngineeringA new pyrene based soluble polymer, namely poly(3,3-didecyl-6-(1-(3,3-didecyl-3,4-dihydro-2H-thieno[3,4-b][1,4] dioxepin-6-yl) pyren-6-yl)-3,4-dihydro-2H-thieno[3,4-b][1,4] dioxepine), P5, which is synthesized by both chemical and electrochemical methods, is highlighted. The polymer shows both electrochromic and fluorescent properties (the emission of yellow (545 nm) and yellowish green light (524 nm) in solid state and in THF solution, respectively). It is noteworthy that P5 has a specific optical band gap (2.2 eV) to reflect the yellow color in the neutral state. Furthermore, the optical and electrochemical features of the polymer were investigated. (C) 2011 Elsevier B. V. All rights reserved.Conference Object Citation - WoS: 5Citation - Scopus: 10Design of a Customer's Type Based Algorithm for Partner Selection Problem of Virtual Enterprise(Elsevier Science Bv, 2016) Nikghadam, Shahrzad; Ozbayoglu, Ahmet Murat; Unver, Hakki Ozgur; Kilic, Sadik EnginVirtual Enterprise (VE) is a temporary platform for individual enterprises to collaborate with each other, sharing their core competencies to fulfill a customer demand. In order to improve the customer satisfaction, the most successful VEs select their consortium's members based on customer's preferences. There is quite extensive literature in the field of partner selection in VE, each proposing a new approach to evaluate and select the most appropriate partners among pool of enterprises. However, none of the studies in literature recommend which partner selection methodology should be used in each project with a particular customer attitude. In this study an algorithm is proposed which classifies the customers into three categories; passive, standard and assertive. Three different approaches; Fuzzy Logic-FAHP TOPSIS and Goal programming are used for each customer type respectively. This classification is beneficial since the problem's characteristics; such as vagueness of data, change as the customer's attitude varies. The results certify that, adopting this algorithm not only helps the VE to select the most appropriate partners based on customer preferences, but also the model adapts itself to each customer's attitude. As a result, the overall system flexibility is significantly improved. (C) 2016 The Authors. Published by Elsevier B.V.
