WoS İndeksli Yayınlar Koleksiyonu
Permanent URI for this collectionhttps://hdl.handle.net/20.500.12573/394
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Conference Object Security Through Digital Twin-Based Intrusion Detection: A Swat Dataset Analysis(IEEE, 2023-10-18) Bozdal, MehmetDigital twin, as a virtual replica of physical entity, offer valuable insights into Industrial Control System (ICS) behavior and characteristics. Leveraging the convergence of digital twins and cybersecurity, this research explores its role in securing critical infrastructure, using the Secure Water Treatment (SWaT) system as a case study. Existing intrusion detection systems (IDS) for SWaT encounter challenges related to requiring huge amounts of a dataset for training, being unable to adopt high data dimensionality, and adaptability to emerging threats. To address these issues, a hybrid digital twin model is proposed, combining physics-based models and data-driven approaches. This model facilitates precise attack localization and explainable IDS outcomes. The method exhibits promising capabilities for enhancing critical infrastructure security and adapting to evolving cyber threats. Experimental results demonstrate the ability to detect eight out of nine attack types.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.Article Tracing Trajectories of Regime Support in Turkey(Ege Univ, Fac Economics & Admin Sciences, 2022-06-09) Inan, MuratAccording to the legitimacy approach of political culture research, public's approval of a particular regime as the best form of government and rejection of its alternatives provides public support for that particular regime. This research attempted to trace temporal trajectories of approval of democratic political system as well as it's three alternative forms of government among the electorates of recent three major political parties in Turkey, the Justice and Development Party (AKP), the Republican People's Party (CHP) and the Nationalist Movement Party (MHP). It also revealed the extent these parties' manifesto documents praise democratic political system across the successive eighteen general elections in the modern Turkish political history. It revealed the changes in both public and party support for four alternative regimes across years in modern Turkish history. This research analyzed the World Values Survey and the Manifesto Project data using quantitative research methods. It has achieved four main findings. First, voters are more stable than their parties across time in terms of pro-democracy. Second, democracy clearly emerges as the strongest alternative among the four alternative regimes for all the three electorates. Third, supporting democracy and rejecting its three alternatives occupy different places in the minds of the three party electorates. Fourth, changes in the three political parties' pro-democracy as identified in their manifesto documents are not always parallel with changes in those of their voters.Conference Object The Investigation of Rayleigh Backscattered Signal Statistics in a Φ-OTDR System Incorporating Optical Pre-Amplifier(IEEE, 2020) Uyar, Faruk; Kartaloglu, Tolga; Ozbay, Ekmel; Ozdur, IbrahimWe theoretically model and experimentally demonstrate the photon statistics of Rayleigh backscattered signal in a phi-OTDR based distributed fiber optical sensor in the presence of amplified spontaneous emission noise caused by optical pre-amplifier. (C) 2020 The Author(s)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.Conference Object Symmetric Electret-Based Vibration Energy Harvesters With Curved-Beam Hinges(IEEE, 2023-05-28) Hah, DooyoungBroadband power spectral characteristics are desirable in vibration energy harvesters, and it can be achieved by employing curved-beam hinges, which exhibit force-displacement nonlinearity. Via numerical analysis by using stochastic differential equations and colored-noise inputs, this study shows that a symmetric configuration of the curved-beam hinges in electret-based harvesters can produce higher (up to 8% more) power outputs than an asymmetric one. It also presents that the harvesters with curved-beam hinges can produce higher (up to 4.4 times) power outputs than those with straight hinges when the vibration magnitude is 0.05g.Conference Object Citation - WoS: 2Student EFL Teachers' Receptive Vocabulary Size(Elsevier Science Bv, 2016-10) Ozonder, OzgulThis study reports the results of a study investigating the receptive vocabulary size of student EFL teachers. The study also examined the relationship between the participants' academic achievement (departmental GPA) and their receptive vocabulary size and the existence of any gender-related difference. The study was carried out in English Language Teaching (ELT) Department of a major state university in Turkey. A total of 104 undergraduate students (females: 76 and males: 28) enrolled in the department voluntarily participated in the study, took the Version 2 of the Vocabulary Levels Tests (Schmitt, Schmitt & Clapham, 2001) and responded to a survey investigating their GPA scores and genders. The results revealed that student EFL teachers have a high level of total receptive vocabulary capacity size in their foreign language (M=103.82). Learners' academic achievement (GPA) is treated as an indicator of their language proficiency level in many studies of English Language Teaching (ELT) field. However, the results of this study revealed that there was not any statistically significant correlation between academic achievement (GPA) and their receptive vocabulary size. Although GPA may be a sign of academic achievement (GPA) and successful studentship, it may not readily one's actual English language proficiency. The results also indicated that there was no significant difference between males and females regarding their receptive vocabulary size. (C) 2016 The Authors. Published by Elsevier Ltd.