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Conference Object Interference Coatings for Infrared Spectroscopy and Colorimetric Sensing(Optica Publishing Group (formerly OSA), 2018) Bakan,G.; Ayas,S.; Ozgur,E.; Celebi,K.; Dana,A.Constructive interference and strong interference surfaces are created to sense ultrathin probe materials such as monolayer protein molecules using enhanced infrared absorption spectroscopy and colorimetric detection, respectively. © 2018 The Author(s).Conference Object Citation - Scopus: 64Performance Analysis of Ad-Hoc Networks Under Black Hole Attacks(Institute of Electrical and Electronics Engineers Inc., 2007) Dokurer,S.; Erten,Y.M.; Acar,C.E.A wireless ad-hoc network is a temporary network set up by wireless nodes usually moving randomly and communicating without a network infrastructure. Due to security vulnerabilities of the routing protocols, however, wireless ad-hoc networks may be unprotected against attacks by the malicious nodes. In this study we investigated the effects of Black Hole attacks on the network performance. We simulated black hole attacks in Network Simulator 2 (ns-2) and measured the packet loss in the network with and without a black hole. We also proposed a simple solution against black hole attacks. Our solution improved the network performance in the presence of a black hole by about 19%. © 2007 IEEE.Article Citation - Scopus: 2Wong’s Oscillation Theorem for the Second-Order Delay Differential Equations(Springer New York LLC, 2017) Özbekler,A.; Zafer,A.[No abstract available]Book Part Citation - Scopus: 3Adaptive Intelligent Learning System for Online Learning Environments(World Scientific Publishing Co., 2013) Serçe,F.C.; Alpaslan,F.N.; Jain,L.C.The present chapter deals with an Adaptive Intelligent Learning System (AILS) which is designed to be used withany Learning Management System (LMS). The adaptiveness provides unique method of identifying and monitoring the learner’s learning processes according to their respectivelearning ability. AILS is a multi-agent system. This was developed in the form of JADE agents. The chapter presents the learning model, the system components, agent behavior in learner scenarios, the ontologies used in agent communications, and adaptive strategies. A sample application of AILS toa dummy LMS is also presented. © 2013 by World Scientific Publishing Co. Pte. Ltd. All rights reserved.Conference Object Energy Dissipation Characteristics of Wireless Sensor Networks With Unidirectional Links;(2012) Özyer,S.T.; Tavli,B.; Koyuncu,M.Link unidirectionality is a commonly encountered phenomena in Wireless Sensor Networks (WSNs), which is a natural result of various properties of wireless transceivers as well as the environment. Transmission power heterogeneity is the dominant factor that creates unidirectional links. In this study, we investigate the impact of transmission power heterogeneity on the lifetime of WSNs through a novel Linear Programming (LP) framework both for networks that utilize only bidirectional links and for those that can use bidirectional links as well as unidirectional links. Our results show that transmission power heterogeneity can lead to more than 25 % decrease in network lifetime for networks that utilize only bidirectional links when compared to a network without any heterogeneity. However, if the use of unidirectional links is also enabled then, the decrease in network lifetime is at most 12 %. © 2012 IEEE.Article Citation - WoS: 18Citation - Scopus: 19A Generalization of Ciric Quasicontractions(Hindawi Publishing Corporation, 2012) Karapinar, Erdal; Kieu Phuong Chi; Tran Duc ThanhWe proved a fixed point theorem for a class of maps that satisfy Ciric's contractive condition dependent on another function. We presented an example to show that our result is a real generalization.Article Citation - WoS: 3Citation - Scopus: 5Equivalent Forms of Single-Operational Transconductance Amplifier Rc Oscillators With Application To Grounded-Capacitor Oscillators(inst Engineering Technology-iet, 2010) Singh, V.It is shown that, given a single-operational transconductance amplifier (OTA) resistor-capacitor (RC) sinusoidal oscillator circuit, it can be put in three other, structurally distinct forms without altering its characteristic equation. This result may facilitate the transformation of some of the available single-OTA RC oscillators employing floating capacitors into the desirable form of employing grounded capacitors. The result turns out to be an aid to a Boolean circuit synthesis method previously given by Tao and Fidler for the generation of single-OTA RC oscillators.Article Citation - WoS: 20Citation - Scopus: 19Electrical Characteristics of Organic Heterojunction With an Alternating Benzotriazole and Fluorene Containing Copolymer(Springer, 2020) Gullu, H. H.; Yildiz, D. E.; Toppare, L.; Cirpan, A.The current-voltage (I - V) and capacitance-voltage (C - V) characteristics of the organic heterojunction diode were investigated in a wide temperature range from 80 to 320 K and frequency range from 10 kHz to 1 MHz, respectively. Alternative to the copolymer partner poly(3-hexylthiophene) (P3HT) to [6,6]phenyl-C61-butyric acid methyl ester (PCBM), poly((9,9-dioctylfluorene)-2,7diyl-(4,7-bis(thien-2-yl)-2-dodecyl-benzo[1,2,3]triazole)) (named as copolymer in this work) was adapted to the bulk-heterojunction layer in the organic diode. Together with the use of Lif/Al bilayer electrode, the diode was fabricated as in the form of Al/LiF/copolymer:PCBM/PEDOT:PSS/ITO/glass. Under the applied bias voltage, this organic-based diode shows two- orders of magnitude rectifying behavior. According to thermionic emission (TE) model, the diode parameters such as saturation current, barrier height and ideality factor were determined and parasitic resistances were also extracted from the conventional ohmic relation. As to the temperature dependency of the diode parameters and their response to the temperature variation, barrier inhomogeneity, surface state and series resistance effects were found in dominant behavior on the current flow. The conduction mechanism was modeled by assuming low-barrier patches around the main barrier that supports TE at low temperatures and their distribution was expressed by a Gaussian function. In addition, series resistance values were detailed depending on temperature using Cheung's model. C - V analysis was performed to evaluate the distribution of surface states at the interface as a function of frequency. Based on the C - V plots, the effects of charges at these traps were observed especially at low frequencies. Additionally, from these results, Fermi level, surface potential and donor concentration values were evaluated in a wide frequency range.Conference Object Jmathnorm: a Database Normalization Tool Using Mathematica(Springer Verlag, 2007) Yazici,A.; Karakaya,Z.This paper is about designing a complete interactive tool, named JMathNorm, for relational database (RDB) normalization using Mathematica. It is an extension of the prototype developed by the same authors [1] with the inclusion of Second Normal Form (2NF), and Boyce-Codd Normal Form (BCNF) in addition to the existing Third normal Form (3NF) module. The tool developed in this study is complete and can be used for real-time database design as well as an aid in teaching fundamental concepts of DB normalization to students with limited mathematical background. JMathNorm also supports interactive use of modules for experimenting the fundamental set operations such as closure, and full closure together with modules to obtain the minimal cover of the functional dependency set and testing an attribute for a candidate key. JMathNorm's GUI interface is written in Java and utilizes Mathematica's JLink facility to drive the Mathematica kernel. © Springer-Verlag Berlin Heidelberg 2007.Article Citation - WoS: 47Citation - Scopus: 54Effects of Smartphone Overuse on Headache, Sleep and Quality of Life in Migraine Patients(Riyadh Armed Forces Hospital, 2019) Demir, Yasemin P.; Sumer, Mehmet M.Objectives: To investigate the effects of smartphone overuse on headache, sleep quality, daytime sleepiness and quality of life in migraine patients. Methods: This study is a single-center, cross sectional comparative study. This study was conducted between July and September 2017 in the Neurology Clinic of a private hospital. Migraine disability assessment MIDAS) questionnaire was used to evaluate the disability status, and Mobile Phone Problematic Use Scale (MPPUS) was used to evaluate smartphone use frequency. The Visual Analogue Scale (VAS), 24-h Migraine Quality of Life Questionnaire (24-h MQoLQ), Pittsburgh Sleep Quality Index (PSQI) and Epworth Sleepiness Scale (ESS) were used to evaluate the pain intensity, quality of life, sleep quality and daytime sleepiness, respectively. Results: The study included a total of 123 patients. There was a significant difference between the groups in terms of pain intensity; frequency and duration as well as VAS, PSQI, 24-h MQoLQ and ESS (p<0.05) scores. There was a negative correlation between MPPUS and PSQI (r=-0.367, p<0.05); a strong positive correlation between MPPUS and ESS (r=0.675, p<0.05) and a negative correlation between MPPUS and 24-h MQoLQ (r=-0.508, p<0.05). Conclusion: Smartphone use has been observed to increase headache duration and frequency in migraine patients. Its overuse in migraine patients is related to poor sleep quality and daytime sleepiness; furthermore, as the smartphone use increases, sleep quality decreases, daytime sleepiness increases and quality of life decreases.
