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Citation - WoS: 3
Citation - Scopus: 4
A 2020 Vision for the Black Sea Region: the Commission on the Black Sea Proposes
(Routledge Journals Taylor & Francis Ltd, 2010) Aydın, Mustafa; Triantaphyllou, Dimitrios
The Black Sea region is coming into its own although it is at times a contested and dangerous neighbourhood. Despite heightened interest in the region its real priorities and needs are still being largely ignored by insiders and outsiders alike. What is needed are regional solutions for regional problems. The authors present the key findings and recommendations of the Commission on the Black Sea a civil society initiative comprising a number of current and former policy-makers scholars and practitioners both from within the region and from outside with the purpose of contributing to a joint vision and a common strategy for the Black Sea region by developing new knowledge in areas of key concern.
Citation - WoS: 5
Citation - Scopus: 6
(3+3+2) Warped-Like Product Manifolds With Spin(7) Holonomy
(Elsevier Science Bv, 2011) Uğuz, Selman; Bilge, Ayşe Hümeyra
We consider a generalization of eight-dimensional multiply warped product manifolds as a special warped product by allowing the fiber metric to be non-block diagonal. We define this special warped product as a (3 + 3 + 2) warped-like manifold of the form M = F x B. where the base B is a two-dimensional Riemannian manifold and the fibre F is of the form F = F-1 x F-2 where the F-i(i = 1 2) are Riemannian 3-manifolds. We prove that the connection on M is completely determined by the requirement that the Bonan 4-form given in the work of Yasui and Ootsuka [Y. Yasui and T. Ootsuka Spin(7) holonomy manifold and superconnection Class. Quantum Gravity 18(2001)807-816] be closed. Assuming that the F-i are complete connected and simply connected it follows that they are isometric to S-3 with constant curvature k > 0 and the Yasui-Ootsuka solution is unique in the class of (3 + 3 + 2) warped-like product metrics admitting a specific Spin(7) structure. Crown Copyright (C) 2011 Published by Elsevier B.V. All rights reserved.
Citation - WoS: 4
Citation - Scopus: 8
Accurate Indoor Positioning With Ultra-Wide Band Sensors
(Tubitak, 2020) Arsan, Taner
Ultra-wide band is one of the emerging indoor positioning technologies. In the application phase, accuracy and interference are important criteria of indoor positioning systems. Not only the method used in positioning, but also the algorithms used in improving the accuracy is a key factor. In this paper, we tried to eliminate the effects of off-set and noise in the data of the ultra-wide band sensor-based indoor positioning system. For this purpose, optimization algorithms and filters have been applied to the raw data, and the accuracy has been improved. A test bed with the dimensions of 7.35 m x 5.41 m and 50 cm x 50 cm grids has been selected, and a total of 27,000 measurements have been collected from 180 test points. The average positioning error of this test bed is calculated as 16.34 cm. Then, several combinations of algorithms are applied to raw data. The combination of Big Bang-Big Crunch algorithm for optimization, and then the Kalman Filter have yielded the most accurate results. Briefly, the average positioning error has been reduced from 16.34 cm to 7.43 cm.
Citation - WoS: 1
Citation - Scopus: 1
Across Dimensions: Two- and Three-Dimensional Phase Transitions From the Iterative Renormalization-Group Theory of Chains
(2020) Keçoğlu, İbrahim; Berker, A. Nihat
Sharp two- and three-dimensional phase transitional magnetization curves are obtained by an iterative renormalization-group coupling of Ising chains, which are solved exactly. The chains by themselves do not have a phase transition or nonzero magnetization, but the method reflects crossover from temperaturelike to fieldlike renormalization-group flows as the mechanism for the higher-dimensional phase transitions. The magnetization of each chain acts, via the interaction constant, as a magnetic field on its neighboring chains, thus entering its renormalization-group calculation. The method is highly flexible for wide application.
Citation - WoS: 18
Citation - Scopus: 25
After the Crimean Crisis: Towards a Greater Russian Maritime Power in the Black Sea
(Routledge Journals Taylor & Francis Ltd, 2014) Delanoe, Igor
The modernization of the Black Sea Fleet currently underway is believed to be one of the most ambitious parts of the Russian State Arms Procurement programme 2011-2020. Up to 18 units are being built and are expected to be commissioned in the Russian Black Sea Fleet by 2020 while new infrastructures are being developed. However Russia's annexation of Crimea in March 2014 has overthrown the Black Sea maritime context. It is likely to give substantial impetus to Russian naval plans in the Black Sea and by extension to sustain Moscow's resumption of naval activity in the Mediterranean. Yet whereas Russia's maritime power has been dramatically enhanced due to the takeover of Crimea Moscow's naval power in the Black Sea and in the Mediterranean remains challenged by a set of qualitative factors. Beyond the Ukrainian crisis has demonstrated the inability of the European Union to manage its Black Sea environment as well as it has highlighted the United States waning influence and interests in the region.
Citation - WoS: 4
Citation - Scopus: 6
Agent-Based Optimization To Estimate Nash Equilibrium in Power Markets
(Taylor & Francis Inc, 2013) Yücekaya, Ahmet; Valenzuela, Jorge
In most deregulated power markets firms bid daily into a day-ahead power market. The auction mechanism supply and demand determine the equilibrium at each hour. In this environment firms aim to maximize their revenues by carefully determining their bids. This requires the development of effective computational methods that help them estimate their competitors' behaviors under incomplete information. In this article an agent-based method that uses particle swarm optimization is described to simulate the behavior of market participants. Particle swarm optimization is used in the bidding process and an agent-based model is applied to find a Nash equilibrium. Different stopping conditions are used to determine the equilibrium. Experimental results are presented for two power systems.
Algı Mı, Söylem Mi? Kopenhag Okulu ve Yeni-klasik Gerçekçilikte Güvenlik Tehditleri
(Uluslararası İlişkiler Konseyi Derneği İktisadi İşletmesi, 2011) Akgül Açıkmeşe, Sinem
Bu makale, güvenlik tehditlerinin ortaya çıkışı bakımından yeni-klasik gerçekçilikteki algısal yaklaşımla, Kopenhag Okulunun söylemle inşaya dayalı yöntemini karşılaştırmaktadır. Makalenin hareket noktası, güvenlik tehditlerinin içeriği ve güvenlik aktörleri bakımından farklı perspektifl ere sahip bu iki yaklaşımın güvenliğin çalışılmasında metodolojik benzerlikler içermesi nedeniyle karşılaştırılabilir olduğu varsayımıdır. Makale, tehditlerin ortaya çıkışı bakımından yeni-klasik gerçekçiliğin algılara dayalı öznel yaklaşımının Kopenhag Okulu tarafından kısmen benimsendiğini vurgulayarak, Okulun söyleme dayalı özneler-arası alternatif bir model geliştirdiğini aktarmaktadır. Bu çerçevede, makale öncelikle Güvenlik Çalışmaları yazınında güvenlik tehdidinin içeriği konusundaki tartışmalara yer vermektedir. Ardından, yeni-klasik gerçekçiliği çatısında barındıran Gerçekçi Güvenlik Çalışmalarının tehdidin içeriği ve ortaya çıkışına dair varsayımlarını karşılaştırmalı olarak değerlendirmekte ve yeni-klasik gerçekçiliğin algısal perspektifi ni analiz etmektedir. Son olarak, Kopenhag Okulunun tehditlerle ilgili analizinin çerçevesini oluşturan güvenlikleştirme yaklaşımının tehditlerin kapsamı ve dayanağına dair tespitlerini Okulun kullandığı söz edimi, siyaset teorisi ve söylem analizi perspektifl erinden yeni-klasik gerçekçilikle karşılaştırmalı olarak incelemektedir.
Amplitude and Frequency Modulations With Cellular Neural Networks
(Springer, 2015) Tander, Baran; Özmen, Atilla
Amplitude and frequency modulations are still the most popular modulation techniques in data transmission at telecommunication systems such as radio and television broadcasting gsm etc. However the architectures of these individual systems are totally different. In this paper it is shown that a cellular neural network with an opposite-sign template can behave either as an amplitude or a frequency modulator. Firstly a brief information about these networks is given and then the amplitude and frequency surfaces of the generated quasi-sine oscillations are sketched with respect to various values of their cloning templates. Secondly it is proved that any of these types of modulations can be performed by only varying the template components without ever changing their structure. Finally a circuit is designed simulations are presented and performance of the proposed system is evaluated. The main contribution of this work is to show that both amplitude and frequency modulations can be realized under the same architecture with a simple technique specifically by treating the input signals as template components.
Citation - WoS: 13
Citation - Scopus: 10
An Analysis of International Relations Academics in Turkey and Their Approaches To the Field: Trip 2014 Faculty Survey Results
(Uluslararası İlişkiler Konseyi Derneği, 2016) Aydın, Mustafa; Hisarlıoğlu, Fulya; Yazgan, Korhan
Despite the increasing interest in the studies inquiring the limits autonomous character of and the interactions between the International Relations (IR) discipline and other academic fields the scope and scale of empirical research on these issues are relatively small. In order to contribute to the discussion on the limits and peculiarities of the IR discipline and to shed light on the development current status and major characteristics of the IR studies in Turkey its place in the global IR discipline and the views of LR. scholars on major issues on the global regional and national agenda two surveys were conducted by the International Relations Council of Turkey (IRCT) in 2007 and 2009. Later on the IRTC collaborated with the Institute for the Theory and Practice of International Relations at the College of William and Mary to conduct further surveys in 2011 and 2014. This paper presents findings of the last survey on Turkey based on the worldwide research simultaneously conducted in 31 different countries in September 2014.
Citation - Scopus: 88
An Analytic Network Process-Based Approach To Concept Evaluation in a New Product Development Environment
(Taylor & Francis, 2007) Ayağ, Zeki; Özdemir, Rifat Gürcan
Selecting the best product concept is one of the most critical tasks in a new product development (NPD) environment. Making decisions at this stage becomes very difficult due to imprecise and uncertain product requirements. So the evaluation process of determining the most satisfying conceptual design has been a very vital issue for companies to survive in fast-growing markets for a long time. Therefore most companies have used various methods to successfully carry out this difficult and time-consuming process. Of these methods an analytic hierarchy process (AHP) has been widely used in multiple-criteria decision-making problems (i.e. concept selection equipment evaluation). In this study however we use an analytic network process (ANP) a more general form of AHP due to the fact that AHP cannot accommodate the variety of interactions dependencies and feedback between higher and lower level elements. Briefly in this paper an ANP-based approach is presented to evaluate a set of conceptual design alternatives in order to reach to the best concept satisfying the needs and expectations of both customers and company. In addition a numerical example is presented to illustrate the proposed approach.
Araştırma Merkezlerinin Yükselişi, Türkiye’de Dış Politika ve Ulusal Güvenlik Kültürü
(Uluslararası İlişkiler Konseyi Derneği İktisadi İşletmesi, 2012) Çelik, Nihat
[Abstract Not Available]
Citation - WoS: 1
Citation - Scopus: 1
Assessing Protein-Ligand Binding Modes With Computational Tools: the Case of Pde4b
(Springer, 2017) Çifii, Gülşah; Aviyente, Viktorya; Akten, Ebru Demet; Monard, Gerald
In a first step in the discovery of novel potent inhibitor structures for the PDE4B family with limited side effects we present a protocol to rank newly designed molecules through the estimation of their IC values. Our protocol is based on reproducing the linear relationship between the logarithm of experimental IC values [(IC)] and their calculated binding free energies (). From 13 known PDE4B inhibitors we show here that (1) binding free energies obtained after a docking process by AutoDock are not accurate enough to reproduce this linear relationship
Citation - WoS: 52
Citation - Scopus: 66
Assessing Quality in Higher Education: New Criteria for Evaluating Students' Satisfaction
(Taylor & Francis, 2011) Zineldin, Mosad; Akdag, Hatice Camgöz; Vasicheva, Valentina
The aim of this research is to present a new quality assurance model (5Qs) and to examine the major factors affecting students' perception of cumulative satisfaction. The model includes behavioural dimensions of student satisfaction. The factors included in this cumulative summation are technical functional infrastructure interaction and atmosphere of higher education institutions. This study concerns students in higher education institutions in Istanbul Turkey. The questionnaire contains a total of 39 items (attributes) of newly developed five quality dimensions (5Qs). A total of 1641 complete and usable questionnaires was received. Frequency analysis factor analysis and reliability analysis were used for analysing the data collected. Inspection of scree plot and eigenvalues enabled the analysis to reduce the 39 quality attributes to seven factors. The results can be used by higher education institutions to re-engineer and re-design creatively their quality-management processes and the future direction of their more effective education quality strategies. © 2011 Taylor & Francis.
Atlantik Paktı’ndan Nato’ya: Türkiye Büyük Millet Meclisi’nde Türkiye’nin Konumu ve Uluslararası Rolü Tartışmalarından Bir Kesit
(Uluslararası İlişkiler Konseyi Derneği İktisadi İşletmesi, 2012) Yanık, Lerna K.
Bu makale Türkiye’nin Kuzey Atlantik İttifakı’na (NATO) giriş sürecinde dış politika söylemleri aracılığıyla oluşan kimliği, eleştirel jeopolitik çerçevesinde irdelemektedir. Bu makalenin ana tezi ülkelerin dış politika yoluyla oluşturdukları kimliklerin sadece konum, kültür ve değerden ibaret olmadığı, bu denkleme bir de ülkelerin üstlendikleri uluslararası işlevin eklenmesi gerektiğidir. Türkiye örneğini değerlendirmek amacıyla Türkiye’nin NATO’ya girişinden hemen önce ve sonrasında Türkiye Büyük Millet Meclisi’nde (TBMM) yapılan çeşitli konuşmalar incelenmiştir. Varılan sonuç bu yıllarda konum, kültür ve değer olarak kendini Batılı sayan Türkiye’nin Doğu’ya uzanmayı görev olarak bellediği ve dolayısıyla üstü kapalı bir eşiksel kimlik yaratıldığıdır.
Citation - WoS: 24
Citation - Scopus: 24
The Availability of Abortion at State Hospitals in Turkey: a National Study
(Elsevier, 2017) O'Neil, Mary Lou
Introduction: Abortion in Turkey has been legal since 1983 and remains so today. Despite this in 2012 the Prime Minister declared that in his opinion abortion was murder. Since then there has been growing evidence that abortion access particularly in state hospitals is being restricted although no new legislation has been offered. Objectives: The study aimed to determine the number of state hospitals in Turkey that provide abortions. Study design: The study employed a telephone survey in 2015-2016 where 431 state hospitals were contacted and asked a set of questions by a mystery patient. If possible information was obtained directly from the obstetrics/gynecology department. I removed specialist hospitals from the data set and the remaining data were analyzed for frequency and cross-tabulations were performed. Results: Only 7.8% of state hospitals provide abortion services without regard to reason which is provided for by the current law while 78% provide abortions when there is a medical necessity. Of the 58 teaching and research hospitals in Turkey 9 (15.5%) provide abortion care without restriction to reason 38 (65.5%) will do the procedure if there is a medical necessity and 11 (11.4%) of these hospitals refuse to provide abortion services under any circumstances. There are two regions encompassing 1.5 million women of childbearing age where no state hospital provides for abortion without restriction as to reason. Conclusion: The vast majority of state hospitals only provide abortions in the narrow context of a medical necessity and thus are not implementing the law to its full extent. It is clear that although no new legislation restricting abortion has been enacted state hospitals are reducing the provision of abortion services without restriction as to reason. Implications: This is the only nationwide study to focus on abortion provision at state hospitals. (C) 2017 Elsevier Inc. All rights reserved.
Back To Full Employment
(Routledge Journals Taylor & Francis Ltd, 2013) Orhangazi, Özgür
[Abstract Not Available]
Citation - WoS: 2
Citation - Scopus: 3
Bargaining With Nonanonymous Disagreement: Decomposable Rules
(Elsevier Science Bv, 2011) Kıbrıs, Özgür; Tapkı, İpek Gürsel
We analyze bargaining situations where the agents' payoffs from disagreement depend on who among them breaks down the negotiations. We model such problems as a superset of the standard domain of Nash (1950). We first show that this domain extension creates a very large number of new rules. In particular, decomposable rules (which are extensions of rules from the Nash domain) constitute a nowhere dense subset of all possible rules. For them, we analyze the process through which "good" properties of rules on the Nash domain extend to ours. We then enquire whether the counterparts of some well-known results on the Nash (1950) domain continue to hold for decomposable rules on our extended domain. We first show that an extension of the Kalai-Smorodinsky bargaining rule uniquely satisfies the Kalai and Smorodinsky (1975) properties. This uniqueness result, however, turns out to be an exception. We characterize the uncountably large classes of decomposable rules that survive the Nash (1950), Kalai (1977), and Thomson (1981) properties. (C) 2011 Elsevier B.V. All rights reserved.
Citation - WoS: 14
Citation - Scopus: 16
Bayesian Compressive Sensing for Primary User Detection
(Inst Engineering Technology-IET, 2016) Başaran, Mehmet; Erküçük, Serhat; Cirpan, Hakan Ali
In compressive sensing (CS)-based spectrum sensing literature most studies consider accurate reconstruction of the primary user signal rather than detection of the signal. Furthermore possible absence of the signal is not taken into account while evaluating the spectrum sensing performance. In this study Bayesian CS is studied in detail for primary user detection. In addition to assessing the signal reconstruction performance and comparing it with the conventional basis pursuit approach and the corresponding lower bounds signal detection performance is also considered both analytically and through simulation studies. In the absence of a primary user signal the trade-off between probabilities of detection and false alarm is studied as it is equally important to determine the performance of a CS approach when there is no active primary user. To reduce the computation time and yet achieve a similar detection performance finally the effect of number of iterations is studied for various systems parameters including signal-to-noise-ratio compression ratio mean value of accumulated energy and threshold values. The presented framework in this study is important in the overall implementation of CS-based approaches for primary user detection in practical realisations such as LTE downlink OFDMA as it considers both signal reconstruction and detection.
Citation - WoS: 3
Citation - Scopus: 3
Bayesian Compressive Sensing for Ultra-Wideband Channel Estimation: Algorithm and Performance Analysis
(Springer, 2015) Özgör, Mehmet; Erküçük, Serhat; Çırpan, Hakan Ali
Due to the sparse structure of ultra-wideband (UWB) channels compressive sensing (CS) is suitable for UWB channel estimation. Among various implementations of CS the inclusion of Bayesian framework has shown potential to improve signal recovery as statistical information related to signal parameters is considered. In this paper we study the channel estimation performance of Bayesian CS (BCS) for various UWB channel models and noise conditions. Specifically we investigate the effects of (i) sparse structure of standardized IEEE 802.15.4a channel models (ii) signal-to-noise ratio (SNR) regions and (iii) number of measurements on the BCS channel estimation performance and compare them to the results of -norm minimization based estimation which is widely used for sparse channel estimation. We also provide a lower bound on mean-square error (MSE) for the biased BCS estimator and compare it with the MSE performance of implemented BCS estimator. Moreover we study the computation efficiencies of BCS and -norm minimization in terms of computation time by making use of the big- notation. The study shows that BCS exhibits superior performance at higher SNR regions for adequate number of measurements and sparser channel models (e.g. CM-1 and CM-2). Based on the results of this study the BCS method or the -norm minimization method can be preferred over the other one for different system implementation conditions.
Citation - WoS: 1
Citation - Scopus: 1
Bayesian Estimation of Discrete-Time Cellular Neural Network Coefficients
(TUBITAK Scientific & Technical Research Council Turkey, 2017) Özer, Hakan Metin; Özmen, Atilla; Şenol, Habib
A new method for finding the network coefficients of a discrete-time cellular neural network (DTCNN) is proposed. This new method uses a probabilistic approach that itself uses Bayesian learning to estimate the network coefficients. A posterior probability density function (PDF) is composed using the likelihood and prior PDFs derived from the system model and prior information respectively. This posterior PDF is used to draw samples with the help of the Metropolis algorithm a special case of the Metropolis--Hastings algorithm where the proposal distribution function is symmetric and resulting samples are then averaged to find the minimum mean square error (MMSE) estimate of the network coefficients. A couple of image processing applications are performed using these estimated parameters and the results are compared with those of some well-known methods.

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