WoS İndeksli Yayınlar Koleksiyonu
Permanent URI for this collectionhttps://hdl.handle.net/20.500.12573/394
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Conference Object Citation - WoS: 2Citation - Scopus: 194.8 Km-Range Direct Detection Fiber Optic Distributed Acoustic Sensor(Optica Publishing Group (Formerly OSA), 2019) Uyar, F.; Onat, T.; Unal, C.; Kartaloǧlu, T.; Ozdur, I.; Özbay, E.This work demonstrates an ultra-long range direct detection fiber optic distributed acoustic sensor which can detect vibrations at a distance of 94.8 km with 10 m resolution along the sensing fiber. © 2023 Elsevier B.V., All rights reserved.Conference Object Citation - WoS: 2Citation - Scopus: 2Cascade Control of Magnetic Levitation with Sliding Modes(EDP Sciences edps@edpsciences.com, 2016) Eroǧlu, Y.; Ablay, G.The effectiveness and applicability of magnetic levitation systems need precise feedback control designs. A cascade control approach consisting of sliding mode control plus sliding mode control (SMC plus SMC) is designed to solve position control problem and to provide a high control performance and robustness to the magnetic levitation plant. It is shown that the SMC plus SMC cascade controller is able to eliminate the effects of the inductance related uncertainties of the electromagnetic coil of the plant and achieve a robust and precise position control. Experimental and numerical results are provided to validate the effectiveness and feasibility of the method. © 2016 Elsevier B.V., All rights reserved.Book Part Citation - WoS: 5Citation - Scopus: 5Wireless MEMS for Smart Grids(Woodhead Publ Ltd, 2017) Tuna, G.; Gungor, V. C.; Dursun, B.Book Part Citation - WoS: 1Citation - Scopus: 4Understanding Communication via Diffusion: Simulation Design and Intricacies(Springer International Publishing AG, 2017) Acar, Bilal; Akkaya, Ali; Genc, Gaye; Yilmaz, H. Birkan; Kuran, M. Sukru; Tugcu, Tuna; Şükrü Kuran, M.Understanding Communication via Diffusion (CvD) is key to molecular communications research since it dominates the movement at the nano-scale. The researcher needs to properly understand the random diffusion of the molecules for the analysis of a molecular communication system. This chapter aims explaining the dynamics of diffusion from a communication engineer's perspective as well as providing useful hints for an effective simulation design by discussing some key intricacies. The chapter starts with a brief survey of simulators for molecular communications, followed by the basics of the simulation of Brownian motion and CvD. Several intricacies are addressed to help the researcher in simulation design, such as the number of replications required in terms of movement and bit sequence. We utilize this information further by discussing the design of more complex CvD systems such as tunnel-based approach that utilizes destroyer molecules and distributed simulator design based on HLA. Introduction of more complex CvD systems provides significant improvements in data rate and communications in general, bridging the gap between human-scale and nano-scale systems and enabling nanonetworking as a viable technology.Conference Object Turkish English Teachers' Professional Teacher Self as One of the Possible Selves(Elsevier Science Bv, 2016-10) Demirezen, Mehmet; Ozonder, OzgulThis study reports the results of a study exploring Turkish English teachers' professional self in relation to teacher education. The study also examines the relationship between the participants' educational background, teaching experience and their professional self The study was carried out in Ankara, Turkey. The participants of the study were English language instructors of Hacettepe University, School of Foreign Languages. A total of 43 English instructors (females: 36 and males: 7) voluntarily participated in the study, responding to a questionnaire composed of 40 items regarding teacher professional self. The results of the Professional Self Questionnaire revealed that the rate of Turkish English teachers' professional self was very high (81%, M=4.09). Also, there was a significant difference in participants' professional self depending on their educational background. The results indicated that the participants' professional self did not differ significantly in relation to their teaching experience. (C) 2016 Published by Elsevier Ltd.Book Part Citation - WoS: 1Turkey(Routledge, 2017) Yoney, Nilufer Baturayoglu; Salman, Yildiz; Polat, Ebru OmayConference Object Thin Films of Inert Metal Nanowires for Display Applications(Tanger Ltd, 2015) Citir, Murat; Sen, Unal; Usta, Hakan; Canlier, Ali; Hakan, Usta; Ali, Canlier; Murat, Citir; Unal, SenAg nanowire transparent electrode has excellent transmittance (90%) and sheet resistance (20 Ohm/sq), yet there are slight drawbacks such as optical haze and chemical instability against aerial oxidation. Chemical stability of Ag nanowires needs to be improved in order for it to be suitable for electrode applications. Coating Ag nanowires with a thin layer of inert metals such as Au and Pd through galvanic exchange reactions may enhance the chemical stability of Ag nanowire films highly and also helps to obtain lower haze. In this study, coating of thin Au and Pd layers has been applied successfully onto the surface of Ag nanowires. Usually coatings are carried out by salts such as HAuCl4 and K2PdCl4 in order to make nanotubes. In this study, novel ethylenediamine(en) complexes of inert metal cations with mild oxidation power were prepared in order to oxidize Ag atoms partially on the surface through galvanic displacement. The mild galvanic exchange allowed for a thin layer (1-4 nm) of inert metal coating on the Ag nanowires with minimal truncation of the nanowire, where the average lengths and the diameters were between 10 similar to 14 mu m and 55 similar to 65 nm, respectively. The crystalline structure of the shell was formed epitaxially on the surface. The new Ag nanowires were suspended in methanol and then electrostatically sprayed on glass and flexible substrates. It was revealed that average total transmittance remain around 90% within visible spectrum region (400-800 nm) whereas sheet resistance rises up to 175 Ohm/sq. Very thin layer of inert metal costs low, though this may render an excellent catalyst for applications such as fuel cell and organic synthesis, whereas transparent films of inert metal-coated Ag nanowire can be utilized as working electrodes for spectro-electrochemical cells as well.Conference Object Citation - WoS: 1The Technology of an Early Reinforced Concrete Structure in Turkey: The Great Storehouse of the Kayseri Sumerbank Textile Factory (1932-1935)(Scuola Pitagora Editrice, 2015) Yoney, Nilufer Baturayoglu; Asiliskender, BurakThe former Kayse`ri Sumerbank Textile Factor(1932-1935) designed and funded by the U.S.S.R. was among the first large-scaled industrial establishments in Turkey. The so-called Great Storehouse as well as the rest of the complex constitutes an interesting case study as an early example of large-scaled reinforced concrete construction in a provincial center for Turkish and Soviet technological history. The long and narrow building measuring 135x45m is constructed in four sections with wide spanning axes based on a skeletal system, supported with slender columns and beams. The columns rise 5-6.5m from the original floor level and reach 9m along the raised central nave. The foundations are composed of double layers of square footings joined with tie beams. The partition walls are constructed with bricks while the exterior walls are tuff. All the masonry walls are held together with a weak mortar based on cement, lime and sand, and with steel reinforcing bars placed horizontally in the horizontal courses and tied to thicker steel bars vertically along the columns. Horizontal strip windows located in the upper part of the exterior walls and along the high central nave provide natural light. There are steel hangar doors along the east and west walls in almost each grid as well as two central doorways located on the short east and west facades. The reinforced concrete surfaces are left exposed while the brick walls and the interior surfaces of the tuff walls are plastered.Article Citation - WoS: 9Citation - Scopus: 11The Intersubband Optical Properties of a Two-Electron Quantum Dot-Quantum Well Heterostructure(Academic Press Ltd- Elsevier Science Ltd, 2015-10) Aydin, Rasit; Tas, Hatice; Sahin, MehmetIn this paper, both linear and third-order nonlinear optical properties of two-electron in a semiconductor core/shell/well/shell quantum dot (QD) heterostructure for cases with and without a hydrogenic donor impurity have been investigated in a detailed manner as depending on the structure parameters. For this purpose, first, the energy eigenvalues and corresponding wave functions of the structure have been computed as a function of the layer thicknesses by means of the self-consistent solution of the Poisson and Schrodinger equations in envelope function effective mass approximation. Second, using these energy eigenvalues and their wave functions obtained from the calculations, both linear and third-order nonlinear optical properties of the multi-shell QD (MSQD) with two-electron have been determined as a function of the photon energies and shell thicknesses. Also, all procedures mentioned above have been repeated for negatively charged donor impurity (D-) located in the center of the same structure. Finally, obtained results have been presented comparatively for cases with and without the impurity. (C) 2015 Elsevier Ltd. All rights reserved.Article Citation - WoS: 4Citation - Scopus: 5The Existence of Positive Solutions for a Semipositone Second-Order M-Point Boundary Value Problem(Dynamic Publishers, inc, 2015) Dogan, AbdulkadirIn this paper, we study the existence of positive solutions to boundary value problem {u '' + lambda f(t,u)=0, t is an element of(0,1); u(0)=Sigma(m-2)(i-1) alpha (i)u(xi(i)), u'(1) = Sigma (m-2)(i=1) beta(i) u'(xi(i)), where xi(i) is an element of(0, 1), 0 < xi(1) < xi(2) < ... < xi(m-2) < 1, alpha(i), beta(i) is an element of[0,infinity), lambda is positive parameter. By using Krasnoserskii's fixed point theorem, we provide sufficient conditions for the existence of at least one positive solution to the above boundary value problem.
