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Article İnsan Kafasındaki Dokuların Öziletkenliklerin Kestirimi İçin Kullanılan İstatistiksel Kısıtlı Minimum Ortalama Hatalar Karesi Algoritmasının Kaynak Yerelleştirimine Etkisi(2012) Şengül, Gökhan; Baysal, UğurEEG ve/veya MEG ölçümleri verildiğinde, insan beynindeki aktif kaynakların bulunması\"EEG/MEG biyoelektromanyetik ters problemi\", \"aktivite kaynağının belirlenmesi\" ya da\"kaynak yerelleştirimi\" (source localization) olarak tanımlanır. Tipik bir kaynak yerelleştirimisistemi EEG/MEG ölçümlerinin yanısıra hastanın/deneğin kafasına ait geometri bilgisine,elektriksel kaynak hakkındaki ön bilgiye, ölçüm elektrotlarının sayısına ve bu elektrotların üçboyutlu uzaydaki konumuna ve kafa modelinde yer alan dokularınöziletkenliklerine/özdirençlerine ihtiyaç duyar. Bu çalışmada insan kafasındaki dokularınöziletkenliklerini kestirmek için daha önce önerilen İstatistiksel Kısıtlı Minimum OrtalamaHatalar Karesi algoritmasının, öziletkenlik kestirimindeki başarımı benzetim çalışmaları ilehesaplanmış ve kaynak yerelleştirimine etkisi araştırılmıştır. Beyin, kafa tası ve kafaderisinden oluşan üç kompartımanlı gerçekçi bir kafa modeli kullanılarak yapılan benzetimçalışmalarında 100 farklı öziletkenlik değeri kestirilmeye çalışılmış ve kestirim hataları kafaderisi için ortalamada %23, kafatası için % 40 ve beyin için de %17 olarak hesaplanmıştır.Çalışmanın ikinci bölümünde ise literatürde verilen ortalama öziletkenlik değerlerikullanıldığında ve önerilen algoritma ile kestirilen öziletkenlik değerleri kullanıldığındaortaya çıkan kaynak yerelleştirimi hataları yine benzetim çalışmaları ile araştırılmıştır.Çalışma sonunda literatürde verilen ortalama öziletkenlik değerleri kullanıldığında 10,1 mmkaynak yerelleştirimi hatası bulunurken önerilen algoritma ile kestirilen öziletkenlik değerlerikullanıldığında ise bu hata 2,7 mm'ye inmiştir. Burada bulunan sonuçlara göre İ.K.M.O.H.K.algoritması ile kestirilen doku öziletkenlikleri kullanıldığında kaynak yerelleştirimi konumhatasında ortalama öziletkenlik kullanılması durumuna göre %73,07'lik azalmagörülmektedir. Sonuç olarak kaynak yerelleştirimi uygulamalarında İ.K.M.O.H.K. algoritmasıile kişiye özgü olarak elde edilen doku öziletkenliklerini kullanmak, ortalama öziletkenlikkullamaya kıyasla hata oranlarını azalttığı sonucuna varılabilir.Conference Object Citation - Scopus: 7Comparative Study of Cognitive Complexity Measures(2008) Misra,S.; Akman,I.Complexity metrics are used to predict critical information about reliability and maintainability of software systems. Cognitive complexity measure based on cognitive informatics, plays an important role in understanding the fundamental characteristics of software, therefore directly affects the understandability and maintainability of software systems. In this paper, we compared available cognitive complexity measures and evaluated cognitive weight complexity measure in terms of Weyuker's properties. © 2008 IEEE.Article Vahdet-i Mevcut’tan Vahdet-i Vücud’a: Anadolu’da İslam Dönemi Sonrasındaki Tanrı Algısının Semah ve Sema Kavramları Aracılığıyla İncelenmesi(2012) Güray, CenkAnadolu’da yaşamış olan tüm uygarlıklar, bu coğrafyaya maddi ve manevi izler bırakmışlardır. Toplumların yaşamsal geleneklerinin önemli bir kısmında etkin bir rol oynayandin ve inanç kültürüne dair simgeler, bu topluluklardan kalmış manevi izlerin en önemlileriarasındadır. Müziğin ve dansın ifade gücü, onları her inanç sistemi için oldukça çekici aktarım araçları haline getirmiştir. Anadolu için inanç ve müzik ilişkisini gerek tarihsel derinlikgerekse de coğrafi yaygınlık açısından en geniş şekilde tanımlayan iki kavram olan semahve sema’nın altyapılarında yatan Vahdet-i Mevcut ve Vahdet-i Vücud felsefeleri aracılığıylaanalizi, Anadolu tarihinin değişik dönemlerindeki insan- Tanrı ilişkisinin dini müzik ve dansyoluyla çözümlenebilmesi için önemli imkânlar sunmaktadır. Bu bağlamda Vahdet-i Mevcutfelsefesinden daha yoğun bir biçimde etkilenmiş olan semah kavramı içinde Tanrı’nın somutolarak tezahürü simgelenirken, bu tezahür Hz. Ali’nin kişiliği aracılığı ile yansıtılmaktadır.Diğer yandan, Vahdet-i Vücud felsefesi doğrultusunda yapılanan sema geleneği içinde iseTanrı’nın bilgisine ulaşarak aşama aşama olgunlaşma gayreti mevcuttur. Ancak sema’da,Tanrı’nın insan vücudunda tezahür etmesi ya da kişileşmesi simgesine rastlanmamakta, sadece insanın maddi ve manevi dünya arasındaki yolculuğu ve bu yolculukta geçirdiği olgunlaşma evreleri ifade edilmektedir. Semah bu anlamıyla vecd ve coşku ile Tanrı ile bir olma,sema ise olgunlaşma, bilgiye mazhar olma ve çile ile Tanrı’nın bilgisinden pay alma anlayışlarını simgelemekte ve iki ayrı insan-Tanrı ilişkisini yani Tanrı algısını ortaya koymaktadır.Conference Object Attitude Control of Cubesat in Single Axis by Fuzzy Logic Controller(Avestia Publishing, 2017) Nazlibilek,S.; Kilickaya,O.G.; Tanyer,S.G.Over the last two decades, satellites are getting smaller with increasing capabilities for space research. Small satellites (between 1 and 15 kg) show great promise as a low-cost option both in production and launching. In this work, attitude control problem for a cubesat is examined. A physical testbed is designed for simulation and testing in a single axis. Cubesat reaction wheel and the testbed are integrated, and fuzzy logic control software in Arduino Mega microprocessor environment is developed. The cubesat floor at the same axis of reaction wheel is tested and real-time measurement data are obtained. Step response and ramp response behaviours are analysed. © 2016 Avestia Publishing.Article Linear Two-Dimensional Consecutive K-Type Systems in Multi-State Case(Elsevier Sci Ltd, 2026) Yi, He; Balakrishnan, Narayanaswamy; Li, XiangIn the context of consecutive k-type systems, multi-state system models are only considered in the onedimensional case and not in the two-dimensional case due to the complexity involved. In this paper, we consider several linear two-dimensional consecutive k-type systems in the multi-state case for the first time, as generalization of consecutive k-out-of-n systems and l-consecutive-k-out-of-n systems without/with overlapping. These systems include multi-state linear connected-(k, r)-out-of-(m, n): G systems, multi-state linear connected-(k, r)-or-(r, k)-out-of-(m, n): G systems, multi-state linear 1-connected-(k, r)-out-of-(m, n): G systems without/with overlapping, and multi-state linear 1-connected-(k, r)-or-(r, k)-out-of-(m, n): G systems without/with overlapping. We then derive their reliability functions by using the finite Markov chain imbedding approach (FMCIA) in a new way. We also present several examples to illustrate all the results developed here.Conference Object Citation - WoS: 68Citation - Scopus: 81Seasonal and Yearly Wind Speed Distribution and Wind Power Density Analysis Based on Weibull Distribution Function(Pergamon-elsevier Science Ltd, 2015) Bilir, Levent; Imir, Mehmet; Devrim, Yilser; Albostan, AyhanWind energy, which is among the most promising renewable energy resources, is used throughout the world as an alternative to fossil fuels. In the assessment of wind energy for a region, the use of two-parameter Weibull distribution is an important tool. In this study, wind speed data, collected for a one year period between June 2012 and June 2013, were evaluated. Wind speed data, collected for two different heights (20 m and 30 m) from a measurement station installed in Atihm University campus area (Ankara, Turkey), were recorded using a data logger as one minute average values. Yearly average hourly wind speed values for 20 m and 30 m heights were determined as 2.9859 m/s and 3.3216 m/s, respectively. Yearly and seasonal shape (k) and scale (c) parameter of Weibull distribution for wind speed were calculated for each height using five different methods. Additionally, since the hub height of many wind turbines is higher than these measurement heights, Weibull parameters were also calculated for 50 m height. Root mean square error values of Weibull distribution functions for each height, derived using five different methods, show that a satisfactory representation of wind data is achieved for all methods. Yearly and seasonal wind power density values of the region were calculated using the best Weibull parameters for each case. As a conclusion, the highest wind power density value was found to be in winter season while the lowest value was encountered in autumn season. Yearly wind power densities were calculated as 39.955 (W/m(2)), 51.282 (W/m(2)) and 72.615 (W/m(2)) for 20 m, 30 m and 50 m height, respectively. The prevailing wind direction was also determined as southeast for the region. It can be concluded that the wind power density value at the region is considerable and can be exploited using small scale wind turbines. Copyright (C) 2015, Hydrogen Energy Publications, LLC. Published by Elsevier Ltd. All rights reserved.Article Citation - WoS: 21Citation - Scopus: 23On (α, Ψ)-k-contractions in the Extended b-metric Space(Univ Nis, Fac Sci Math, 2018) Alqahtani, Badr; Karapinar, Erdal; Ozturk, AliIn this paper, we introduce a notion of (alpha, psi)-K-contraction in the setting of extended b-metric spaces and investigate the existence of a fixed point. The presented results generalize and unify a number of well-known fixed point theorem mainly in two distinct aspects; in the sense of the contraction conditions and in the frame of abstract spaces.Conference Object Citation - WoS: 7Citation - Scopus: 7Synthesis, Characterizations and Investigation of Thermoluminescence Properties of Strontium Pyrophosphate Doped With Metals(Pergamon-elsevier Science Ltd, 2014) Ilkay, L. S.; Ozbayoglu, G.; Yilmaz, A.Strontium pyrophosphate, Sr2P2O7, was synthesized by solid-state synthesis method; the product was co-doped with copper-silver (Cu-Ag), copper-indium (Cu-In) and manganese-praseodymium (Mn-Pr) oxides (CuO, MnO, In2O3, Pr6O11 and AgNO3) by solid-state reaction method. The variation of dopant concentrations was investigated from 0.5 to 15% by weight. In addition to these processes, chemical characterizations of samples and the investigation of thermoluminescence (TLD) properties of strontium pyrophosphate with and without dopants were conducted. For the characterization; powder X-ray Diffraction (XRD) were implemented for phase purity of samples. Fourier Transform Infrared Spectroscopy (FTIR) was used to determine whether the bond structures were affected from the doping or not. Thermoluminescence (TLD) analyses were conducted on strontium pyrophosphate doped with different amounts of dopants for the first time. Glow curves showed that intensities were affected by different amounts of dopants. It can be concluded from that strontium pyrophosphate doped with 7% MnO and 1% Pr6O11 had the most powerful peak intensity around 160 degrees C and dosimetric property for promising application. (C) 2014 Elsevier Ltd. All rights reserved.Conference Object Citation - WoS: 12An Architectural Model for System of Information Systems(Springer int Publishing Ag, 2015) Majd, Saleh; Marie-Helene, Abel; Mishra, AlokOne of the most important aspects when designing and constructing an Information System is its architecture. This also applies to complex systems such as System of Information Systems (SoIS). Thus, we aim to propose an architectural model of System of Information Systems (SoIS). Though Architecture-based approaches have been promoted as a means of controlling the complexity of systems construction and evolution, what we really look for in this paper is an architectural model to aggregate services from already constructed systems. Nevertheless, it would be a good practice to compare the presented architecture of SoIS to other architecture-based approaches such as Service Oriented Architecture (SOA). Also, it is beneficial to examine how we can use the well-established standards of SOA for the designing of SoIS. In this paper we present an architectural model for System of Information Systems, and highlight the standards of Service Oriented Architecture that might help us in this task.Book Part Citation - Scopus: 3Making Foreign Policy Through Twitter: an Analysis of Trump's Tweets on Iran(IGI Global, 2020) Orhan,D.D.Through the development of technology, the understanding of traditional foreign policy has changed. Foreign policy making, which was shaped by diplomatic correspondence, visits, agreements, and notes between countries, is carried out today via messages sent over the Internet. Twitter is the most frequently used internet tool in the hands of institutions, decision makers, and leaders in foreign policy making. US President Donald J. Trump is one of the leaders who use Twitter most effectively. Twitter was the center of Trump's messages, both during the presidential campaign and after his election. Trump is not just using Twitter as a platform for meeting his supporters and announcing the country's official policies. Twitter has also been an important way for Trump to challenge and send harsh messages to certain countries, companies, and individuals. Iran is one of the countries that Trump targets through Twitter. This study aims to examine the use of Twitter as a platform in foreign policy making by using content analysis method through Trump's tweets about Iran. © 2021, IGI Global.
