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Yayın Realities & constraints of coal from energy and environmental perspectives(University of Pittsburgh, 2010) Ekinci, Ekrem[No abstract available]Yayın Topography of inland deltas: Observations, modeling, and experiments(Amer Geophysical Union, 2010-04-28) Seybold, Hansjörg J.; Molnar, Peter; Akça, Mehmet Devrim; Doumi, M.; Tavares, M. Cavalcanti; Shinbrot, Troy; Andrade, Jose Soares; Kinzelbach, Wolfgang; Herrmann, Hans JürgenThe topography of inland deltas is influenced by the water-sediment balance in distributary channels and local evaporation and seepage rates. In this letter a reduced complexity model is applied to simulate inland delta formation, and results are compared with the Okavango Delta, Botswana and with a laboratory experiment. We show that water loss in inland deltas produces fundamentally different dynamics of water and sediment transport than coastal deltas, especially deposition associated with expansion-contraction dynamics at the channel head. These dynamics lead to a systematic decrease in the mean topographic slope of the inland delta with distance from the apex following a power law with exponent alpha = -0.69 +/- 0.02 where the data for both simulation and experiment can be collapsed onto a single curve. In coastal deltas, on the contrary, the slope increases toward the end of the deposition zone.Yayın The sectoral sweeper scheme for wireless sensor networks: Adaptive antenna array based sensor node management and location estimation(Kluwer Academic Publishers-Plenum Publishers, 2006-12) Erdoğan, Ayhan; Coşkun, Vedat; Kavak, AdnanWe introduce a novel sensor node management and location estimation method referred as sectoral sweeper (SS) scheme that uses an adaptive antenna array (AAA) at a central node in wireless sensor networks (WSNs). With the SS scheme, the central node can activate or deactivate the nodes in a desired region which is specified by beam direction and beam width of the transmit beam and also by minimum and maximum thresholds (R (min) and R (max)) for the received signal strength indicator (RSSI) of signals received by the nodes. In order to perform a specified task that is associated with a Task_id, two different beams are transmitted, which are task region beam and routing region beam to switch the nodes into active or routing modes. Since our scheme does not require any additional software or hardware for node management and location estimation in sensor nodes, the deficiencies of tiny sensors are effectively eliminated. The proposed scheme is shown to reduce the number of sensing nodes and the amount of data traffic in the network, thus leading to considerable savings in energy consumption and prolonged sensor lifetime.Yayın Yakın alan iletişimi teknolojisi(Türkiye Bilişim Vakfı, 2016-06-24) Özdenizci, Büşra; Ok, Kerem; Aydın, Mehmet Nafiz; Coşkun, VedatYakın Alan İletişimi iki elektronik cihazın kısa mesafede, yüksek frekansta ve düşük bant genişliğinde haberleşmesini sağlayan Radyo Frekansı ile Tanımlama tabanlı bir teknolojidir. NFC uygulamaları temel olarak üç ayrı çalışma kipi kullanırlar ve her bir kipin kullanımının getirmiş olduğu ayrı özellikler ve avantajlar mevcuttur. Her çalışma kipi farklı iş fırsatları ve katma değer olanakları sunabilmektedir. Bu çalışmada, öncelikle dünyada şu an itibari ile mevcut tüm NFC uygulamaları ve prototipleri, kullanmış oldukları çalışma kiplerine göre incelenmiştir. Daha sonra bu çalışmaların her biri ayrıntılı biçimde analiz edilmiş ve oluşturdukları katma değer ortaya konulmuştur. Çalışma, bu alandaki hedef beklentilerimizin konulması ile neticelendirilmiştir.Yayın Primitives of service oriented information system development(2011) Aydın, Mehmet Nafiz; Yalçınkaya, TayfunOne can find the long standing problems with conceptual modeling such as model transformation, reusability and agility in the classical information system development (ISD). New approaches may help in overcoming these issues in conventional ISD's problems. The service oriented approach which is one of the promising approaches, brings solutions to some existing problems. By adopting service orientation in ISD - which we call service oriented ISD, one can deal with the aforementioned problems. This study examines the very notion of service in the context of conceptual modeling method. In particular, we show how to support service modeling in terms of guidance (that is, the way of modeling). The proposed modeling support is demarcated along with a method at the foundational level. The paper is a conceptual and work-in-progress paper.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 Comments on "upper cutoff frequency of the bound wave and new leaky wave on the slotline"(IEEE-INST Electrical Electronics Engineers Inc, 1999-05) İdemen, Mehmet Mithat; Büyükaksoy, İbrahim Alinur[No abstract available]Yayın Deterministic local doubling of W states(OSA - The Optical Society, 2016-11-01) Yeşilyurt, Can; Buğu, Sinan; Özaydın, Fatih; Altıntaş, Azmi Ali; Tame, Mark S.; Yang, Lan; Özdemir, Şahin KayaIn large quantum systems, multipartite entanglement can be found in many inequivalent classes. Preparing states of arbitrary size in different classes is important for performing a wide range of quantum protocols. W states, in particular, constitute a class with a variety of quantum networking protocols. However, all known schemes for preparing polarization encoded photonic W states are probabilistic, with resource requirements increasing at least sub-exponentially. We propose a deterministic scheme for preparing W states of size of any power of 2, which requires no prior entanglement and can be performed locally. We introduce an all-optical setup that can efficiently double the size of W states of arbitrary size. Our scheme advances the use of W states in real-world quantum networks and could be extended to other physical systems.Yayın Optimal deployment in randomly deployed heterogeneous WSNs: A connected coverage approach(Academic Press Ltd- Elsevier Science Ltd, 2014-11) Sevgi, Cüneyt; Koçyiğit, AltanWireless sensor networks (WSNs) are resource-scarce networks and the optimization of the resources is challenging. As far as random deployment is concerned, the optimization of these resources becomes even more difficult In this paper, a novel framework is proposed for solving optimal deployment problems for randomly deployed and clustered WSNs. In several existing approaches to solve these problems, either only partial-coverage is considered or only connectivity is analyzed when full-coverage is assured. Through this study, we aim to contribute to the better understanding of partial connected coverage. For this purpose, we introduce cluster size formulations which provide network designers with estimating partial-coverage easily. While the proposed framework facilitates our cluster size formulations for coverage estimations, it also adopts the percolation theory to analyze the degree of connectivity when the targeted degree of partial-coverage is achieved. As the partial connected coverage approach reflects real-life deployment scenarios, the use of percolation theory results in generic solutions of optimal deployment problems, which indeed makes the solution independent from any routing algorithms. Moreover, a practical optimal deployment problem is formulated to find the cheapest WSN application that satisfies the targeted degree of partial connected coverage. Further, in this paper, the cost effectiveness of the node heterogeneity is investigated through comparing the heterogeneous WSNs with their homogeneous counterparts.Yayın Preparing multipartite entangled spin qubits via pauli spin blockade(Nature Research, 2020-02-26) Buğu, Sinan; Özaydın, Fatih; Ferrus, Thierry; Kodera, TetsuoPreparing large-scale multi-partite entangled states of quantum bits in each physical form such as photons, atoms or electrons for each specific application area is a fundamental issue in quantum science and technologies. Here, we propose a setup based on Pauli spin blockade (PSB) for the preparation of large-scale W states of electrons in a double quantum dot (DQD). Within the proposed scheme, two W states of n and m electrons respectively can be fused by allowing each W state to transfer a single electron to each quantum dot. The presence or absence of PSB then determines whether the two states have fused or not, leading to the creation of a W state of n + m ? 2 electrons in the successful case. Contrary to previous works based on quantum dots or nitrogen-vacancy centers in diamond, our proposal does not require any photon assistance. Therefore the ‘complex’ integration and tuning of an optical cavity is not a necessary prerequisite. We also show how to improve the success rate in our setup. Because requirements are based on currently available technology and well-known sensing techniques, our scheme can directly contribute to the advances in quantum technologies and, in particular in solid state systems.
