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Yayın The survey on Near Field Communication(MDPI, 2015-06) Coşkun, Vedat; Özdenizci Köse, Büşra; Ok, KeremNear Field Communication (NFC) is an emerging short-range wireless communication technology that offers great and varied promise in services such as payment, ticketing, gaming, crowd sourcing, voting, navigation, and many others. NFC technology enables the integration of services from a wide range of applications into one single smartphone. NFC technology has emerged recently, and consequently not much academic data are available yet, although the number of academic research studies carried out in the past two years has already surpassed the total number of the prior works combined. This paper presents the concept of NFC technology in a holistic approach from different perspectives, including hardware improvement and optimization, communication essentials and standards, applications, secure elements, privacy and security, usability analysis, and ecosystem and business issues. Further research opportunities in terms of the academic and business points of view are also explored and discussed at the end of each section. This comprehensive survey will be a valuable guide for researchers and academicians, as well as for business in the NFC technology and ecosystem.Yayın Luminescence ages of feldspar contaminated quartz from fluvial terrace sediments(Wind-J Wojewoda Publ Co, 2008-01-01) Güneç Kıyak, Nafiye; Erturaç, Mehmet KorhanThis study focuses on obtaining luminescence ages in feldspar contaminated quartz from well-developed fluvial terraces of the Yesilirmak (Iris) river located inside the eastern North Anatolian Fault Shear Zone (NAFZ). We applied a technique based on conventional single-aliquot regenerative-dose (SAR) protocol, modified with an IR pre-treatment to reduce the OSL contribution from feldspar for accurately measuring the dose in quartz. All investigated samples showed an ability to measure a beta dose given in the laboratory, a so called dose recovery test. The dependence of the equivalent dose on thermal treatment was also examined. Dose rate calculations were based on spectral analysis of gamma measurements by a field spectrometer on site. The efforts to establish a chronology using the IR modified SAR technique produced reliable dose results in stratigraphic order. Results were reproducible and grouped broadly between 35-109 ka for Bektemur, 32-36 ka for Kizilca, 19-47 ka for Aksalur and 35-44 ka for Sahinkaya. Obtained results show that the studied area was controlled by tectonic activities within the last 50 ka and the sample Aksalur 2 was the loess deposit formed by aeolian activity.Yayın Investigation of the OSL signal from very deep traps in natural quartz(Univ Agean, Dept Mediterranean Stud, 2010) Kitis, George; Güneç Kıyak, Nafiye; Polymeris, George S.; Pagonis, VasilisIt has been recently reported by several studies that a thermally transferred optically stimulated luminescence (TT-OSL) signal from quartz grains can be used to extend the dating range for quartz samples. The TT-OSL signals are believed to consist of a recuperated OSL (ReOSL) component and a basic-transferred OSL (BT-OSL) component. In the present work the TT-OSL signals from several types of unfired quartz samples were studied. A special protocol was used, which allowed the measure the OSL from very deep traps (VDT) as a function of the OSL stimulation temperature. It was found that all quartz samples exhibit TT-OSL signals, which are depended on sample and on the OSL stimulation temperature. The activation energy of the process was evaluated and the influences of the TT-OSL on the ReOSL dating protocol are discussed.Yayın Component resolved IR bleaching study of the blue LM-OSL signal of various quartz samples(Wind-J Wojewoda Publ Co, 2008-01-01) Polymeris, George S.; Güneç Kıyak, Nafiye; Kitis, GeorgeThe present work provides an initial component resolved analysis concerning the effect of infra-red (IR) exposure at elevated temperatures on the blue LM-OSL signal of quartz (stimulated at 470 nm). The study was performed on a total of seven quartz samples, among which five originated from Turkey, one from Greece and one synthetic quartz sample. For these quartz samples, the presence of 6 or even 7 independent LM-OSL components was previously reported, after the application of a computerized decomposition analysis. IR bleaching of each one of these components is studied and compared to the respective signal reduction due to the same thermal treatment solely. It is clearly demonstrated that IR stimulation at temperatures above 50 degrees C does not deplete only the fast component in most sedimentary quartz samples studied. Net depletion of fast and medium components resulting from IR exposure is sample-dependent and occurs faster as the stimulation temperature increases. Weak IR bleaching of slow components is also reported in some cases, being more effective for stimulation temperatures up to 100 degrees C. No depletion of either the medium or the slow components was detected for stimulation temperatures above 150 degrees C. Finally, IR does not stimulate any of the LM-OSL components in the case of the synthetic quartz sample.
