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Yayın Behavior of quantum fisher information of bell pairs under decoherence channels(Polish Acad Sciences Inst Physics, 2014-02) Özaydın, Fatih; Altıntaş, Azmi Ali; Buğu, Sinan; Yeşilyurt, CanQuantum Fisher information has recently been an essential tool for analyzing the phase sensitivity of the quantum states in various quantum tasks, requiring high precision, such as quantum clock synchronization, positioning and many applications which include quantum interferometers. Due to the interactions with the environment, all quantum systems are subject to various decoherence effects. Therefore the research on quantum Fisher information under decoherence has been recently attracting more attention. In this work, analyzing the quantum Fisher information, we study the phase sensitivity of bipartite quantum correlations, in particular four Bell pairs amplitude damping channels. For a specific Bell state we arrive at similar results of Greenberger-Horne-Zeilinger (GHZ) states (as expected). For the other three Bell states, we present our results which point the interesting behavior of quantum Fisher information with respect to the decoherence rate. We also find the regions where the quantum Fisher information exhibits discontinuities.Yayın A novel method to design wideband power amplifier for wireless communication(IEEE, 2013) Köprü, Ramazan; Kuntman, Hulusi Hakan; Yarman, Bekir Sıddık BinboğaA new approach is presented to design microwave amplifiers to deliver maximum output power using Simplified Real Frequency Technique (SRFT). Proposed method tracks the maximum stable gain (MSG) curve of the active device (BJT, FET etc.) under consideration. Maximum Stable Gain Amplifier (MSGA) possesses higher gain than that of the constant or Flat Gain Amplifier (FGA) along the operating frequency band. Compared to FGA, it is this feature that makes MSGA high efficiency and low DC power consumption amplifier. Employing the proposed design method, a MSG power amplifier is constructed over the frequency band of 800-5200 MHz which can be utilized for GSM, UMTS, Wi-Fi and Wi-MAX applications.Yayın A parallel implementation: Real space Green's function technique(Sage Publications, 2007-04) Onat, Berk; Durukanoğlu, Sondan; Dağ, HasanWe develop an MPI-based parallel algorithm to implement the real space Green's function technique for calculating the vibrational density of states corresponding to a solid. The Hamiltonian describing the interactions between the atoms within the system is obtained from the embedded atom method. The parallel implementation speeds up calculation by an order of magnitude. The parallel implementation details and results are presented in this paper.Yayın NFC loyal system on the cloud(IEEE Computer Society, 2013) Coşkun, Vedat; Özdenizci Köse, Büşra; Ok, Kerem; Alsadi, MohammedFC (Near Field Communication) technology facilitates mobile phone usage of billions of people throughout the world that offers diverse services ranging from payment and loyalty applications to access keys for offices and houses. NFC technology is one promising technology that have adopted smart card as secure element (SE) to provide a secure area for the execution of multiple applications and storing sensitive data. In this paper, we developed a framework to integrate NFC loyal system onto the cloud. We adapted NFC mobiles together with their SE to the cloud (Infrastructure as a Service - IaaS) using Cloud Computing methodology.Yayın İki qubit’lik kuantum haberleşme ağlarının eş zamanlılık donanıklık ölçütü ile kuantum Fisher bilgisinin analizi(IEEE, 2014-06-12) Erol, Volkan; Buğu, Sinan; Özaydın, Fatih; Altıntaş, Azmi AliKuantum dolanıklık, kuantum haberleşme mühendisliğinin en temel kavramlarından biridir. Kuantum sistemlerin dolanıklık ölçütlerine göre sıralanması günümüzde oldukça çok çalışılan konulardan birisidir. İki parçacıklı iki seviyeli sistemlerin (qubit) sıralaması konusu, çok bilinen Eş Zamanlılık (Concurrence), Negatiflik (Negativity) ve Dolanıklığın Göreceli Entropisi (REE) ölçütlerine göre çeşitli araştırmacılar tarafından çalışılmıştır[1-5]. Biz bu çalışmada, iki qubit kuantum sistemlerin sıralamasını Kuantum Fisher Bilgisi ve Eş Zamanlılık dolanıklık ölçütünü karşılaştıracak şekilde analiz etmekteyiz. Çalışma özelinde, bin adet rastgele türetilmiş iki qubit sistemin Eş Zamanlılık değerleri hesaplanmakta; elde ettiğimiz bu sonuçların iki qubit sistemlerde Kuantum Fisher Bilgisi ile karşılaştırılması yapılmakta ve aralarındaki ilginç farklar gözlemlenmektedir.Yayın On the identification of microstretch elastic moduli of materials by using vibration data of plates(Pergamon-Elsevier Science LTD, 2008-06) Kırış, Ahmet; İnan, EsinIn the present work, the vibration problems of rectangular plates modeled by Eringen's microstretch theory are investigated for the identification of the upper bounds of the microstretch moduli of the plate material. The calculated frequencies of the plates are obtained by extending the Ritz method to the microstretch plates. The three dimensional (3D) vibration analysis of the plates shows that some additional frequencies occur among the classical frequencies as characterizing the microstretch effects. Then it is also observed that these additional frequencies disappear and only the classical frequencies remain with the increasing values of microstretch constants. The inverse problem is established for the identification of the upper bounds of the microstretch elastic constants as an optimization problem where an error function is minimized.Yayın Estimation of microstretch elastic moduli by the use of vibrational data(Springer, 2007) Kırış, Ahmet; İnan, EsinIn the present work, a nonlinear wave theory is used for the estimation of the material properties of a "microstretch" medium. For this purpose a thin plate is considered and triplicate Chebyshev polynomial series are used as admissible functions to ensure the satisfaction of geometric boundary conditions of the plate. The Ritz technique is applied to derive the frequency equation of the microstretch plate and an optimization procedure is performed by minimising the least square "distance" between computed natural frequencies from the energy method and measured natural frequencies. To realize the optimization procedure, a genetic algorithm is used to estimate the elastic moduli of microstretch medium.Yayın Kübit-Kütrit kuantum haberleşme sistemleri için negatiflik ve dolanıklığın göreceli entropisi ölçütlerinin analizi(IEEE, 2015-06-19) Erol, Volkan; Özaydın, Fatih; Altıntaş, Azmi AliKuantum Bilgi Teorisi ve Kuantum Hesaplama konuları geleceğin bilgisayar teknolojisi olarak nitelendirilen ve çok yüksek hızlarda işlem yapacak olması öngörülen Kuantum Bilgisayarlarının teorik temelini oluşturan oldukça sıcak çalışma alanlarıdır. Kuantum Bilgisayarlarında bilginin taşınacağı birim kübit olarak nitelendirilse de, bazı problemler için bu birimlerin üç seviye (trinary) olan kütritlerce kurgulanabileceği teorik olarak gösterilmiştir. Bu çalışma kapsamında, kübit-kütrit Kuantum Haberleşme Sistemlerinin dolanıklıklığını ölçmek için kullanılan Negatiflik ve Dolanıklığın Göreceli Entropisi ölçütlerinin karşılaştırmalı analizi yapılmıştır. Bu bağlamda, rastgele türetilmiş 1000 adet kübit-kütrit sistem durumlarının adı geçen ölçütleri hesaplanmış ve bu değerler sistem durumlarının sıralanması amacıyla karşılaştırılmıştır. Yapılan analiz kapsamında sistem durumlarının sıralaması problemi açısından oldukça ilginç sonuçlar gözlemlenmiştir.Yayın Getting agile methods to work for cordys global software product development(Springer-Verlag Berlin, 2011-03-14) Van Hillegersberg, Jos; Ligtenberg, Gerwin; Aydın, Mehmet NafizGetting agile methods to work in global software development is a potentially rewarding but challenging task. Agile methods are relatively young and still maturing. The application to globally distributed projects is in its early stages. Various guidelines on how to apply and sometimes adapt agile methods have been proposed. However, systematic literature reviews reveal that detailed evaluative studies are scarce and limited to small and medium sized projects. This study presents a framework that integrates best practices of adapting and applying agile methods reported in the literature. The framework is applied to analyze the experiences of global software product development company Cordys in a seven year longitudinal case study. Both the framework and the experiences of Cordys documented in this paper will be of value to other larger projects that aim to he successful in applying agile in globally distributed projects.Yayın Quantum fisher information of bipartitions of W states(Polish Acad Sciences Inst Physics, 2015-04-24) Özaydın, Fatih; Altıntaş, Azmi Ali; Yeşilyurt, Can; Buğu, Sinan; Erol, VolkanWe study the quantum Fisher information (QFI) of W states and W-like states under decoherence. In particular, we find that on the contrary to amplitude damping and depolarizing decoherence, a W-like state of 3 qubits obtained by discarding 1 qubit of a genuine W state of 4 qubits is more robust than a genuine W state of 3 qubits under amplitude amplifying and phase damping decoherence.
