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Citation Count: 1
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 Count: 5
(3+3+2) warped-like product manifolds with Spin(7) holonomy
(Elsevier Science Bv, 2011) Bilge, Ayşe Hümeyra; 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 Count: 20
Activating reflective thinking with decision justification and debiasing training
(Society for Judgment and Decision making, 2020) Yılmaz, Onurcan; Doğruyol, Burak; Doğruyol, Burak
Manipulations for activating reflective thinking, although regularly used in the literature, have not previously been systematically compared. There are growing concerns about the effectiveness of these methods as well as increasing demand for them. Here, we study five promising reflection manipulations using an objective performance measure — the Cognitive Reflection Test 2 (CRT-2). In our large-scale preregistered online experiment (N = 1,748), we compared a passive and an active control condition with time delay, memory recall, decision justification, debiasing training, and combination of debiasing training and decision justification. We found no evidence that online versions of the two regularly used reflection conditions — time delay and memory recall — improve cognitive performance. Instead, our study isolated two less familiar methods that can effectively and rapidly activate reflective thinking: (1) a brief debiasing training, designed to avoid common cognitive biases and increase reflection, and (2) simply asking participants to justify their decisions.
Citation Count: 4
An Adaptive Affinity Matrix Optimization for Locality Preserving Projection via Heuristic Methods for Hyperspectral Image Analysis
(IEEE-Inst Electrıcal Electronıcs Engıneers Inc, 2019) Ceylan, Oğuzhan; Ceylan, Oğuzhan
Locality preserving projection (LPP) has been often used as a dimensionality reduction tool for hyperspectral image analysis especially in the context of classification since it provides a projection matrix for embedding test samples to low dimensional space. However, the performance of LPP heavily depends on the optimization of two parameters of the graph affinity matrix: k-nearest neighbor and heat kernel width, when one considers an isotropic kernel. These two parameters might be optimally chosen simply based on a grid search. In case of using a generalized heat kernel where each feature is separately weighted by a kernel width, the number of parameters that need to be optimized is related to the number of features of the dataset, which might not be very easy to tune. Therefore, in this article, we propose to use heuristic methods, including genetic algorithm (GA), harmony search (HS), and particle swarm optimization (PSO), to explore the effects of the heat kernel parameters aiming to analyze the embedding quality of LPP's projection in terms of various aspects, including 1-NN classification accuracy, locality preserving power, and quality of the graph affinity matrix. The results obtained with the experiments on three hyperspectral datasets show that HS performs better than GA and PSO in optimizing the parameters of the affinity matrix, and the generalized heat kernel achieves better performance than the isotropic kernel. Additionally, a feature selection application is performed by using the kernel width of the generalized heat kernel for each heuristic method. The results show that very promising results are obtained in comparison with the state-of-the-art feature selection methods.
Citation Count: 13
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 Count: 36
Alevis and Alevism in the Changing Context of Turkish Politics: The Justice and Development Party's Alevi Opening
(Routledge Journals Taylor & Francis Ltd, 2011) Soner, Bayram Ali; Toktaş, Şule
The Justice and Development Party (JDP Adalet ve Kalkinma Partisi) has launched a rapprochement policy toward the Alevis. The JDP's Alevi Opening has presented a unique case in Turkey's latest identity politics not only because Alevi claims for the first time came to be involved in political processes for official recognition and accommodation but also because the process was handled by a political party which is regarded to have retained Islamist roots in Sunni interpretation. This article explores the JDP's Alevi Opening process and tries to explain the motivations behind the party's decision to incorporate the Alevi question in its political agenda. What is more the debate that the opening has caused is also under scrutiny with the positions and arguments held by the actors and the agencies involved in the process e. g. the Alevis (the secularist and the conservative wings) the General Directorate of Religious Affairs the National Security Council the JDP leadership and the Islamist intellectuals.
Citation Count: 11
All the Dark Triad and some of the Big Five traits are visible in the face
(Pergamon-Elsevıer Scıence Ltd, 2021) Yılmaz, Onurcan; Bayrak, Fatih; Yılmaz, Onurcan
Some of the recent studies suggested that people can make accurate inferences about the level of the Big Five and the Dark Triad personality traits in strangers by only looking at their faces. However, later findings provided only partial support and the evidence is mixed regarding which traits can be accurately inferred from faces. In the current research, to provide further evidence on whether the Big Five and the Dark Triad traits are visible in the face, we report three studies, two of which were preregistered, conducted on both WEIRD (the US American) and non-WEIRD (Turkish) samples (N = 880). The participants in both the US American and Turkish samples were successful in predicting all Dark Triad personality traits by looking at a stranger's face. However, there were mixed results regarding the Big Five traits. An aggregate analysis of the combined dataset demonstrated that extraversion (only female), agreeableness, and conscientiousness were accurately inferred by the participants in addition to the Dark Triad traits. Overall, the results suggest that inferring personality from faces without any concrete source of information might be an evolutionarily adaptive trait.
Citation Count: 0
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 Count: 5
Analysis of Mixed-Element Structures Formed With Shunt Capacitors Separated by Transmission Lines
(IEEE-Inst Electrical Electronics Engineers Inc, 2019) Şengül, Metin Y.; Çakmak, Gökhan
In this brief, the analysis of mixed-element structures formed with shunt capacitors separated by commensurate transmission lines is performed first time in the literature. First, a low-pass lumped-element ladder network is considered. Then the series inductors are replaced with commensurate transmission lines. As a result, a practically important mixed-element structure is obtained. Then the description of the structure by means of two frequency variables (one for shunt capacitors and one for transmission lines) is detailed: Explicit expressions for the coefficients of the descriptive two-variable polynomials in terms of the coefficients of the single variable boundary polynomials are derived for various numbers of elements, which are obtained first time in the literature. Finally, a mixed-element broadband matching network is designed to illustrate the usage of the obtained expressions. If it is preferred not to have shunt capacitors, they can be replaced with open-ended stubs via Richard's transformation. So the resultant circuit is extremely suitable for microstrip fabrication.
Citation Count: 5
An analysis of price spikes and deviations in the deregulated Turkish power market
(Elsevier, 2019) Bilge, Ayşe Hümeyra; Yücekaya, Ahmet; Bilge, Ayşe Hümeyra
The successful operation of a real time market is related to the planning in the day ahead market. We analyze the day ahead and real time market data for the Turkish power market for the period 2012-2015 to classify price spikes and their causes. We also focus on the levels of deviation between the day ahead market values and the real time market values. We define price deviation and load deviation ratios to measure the level of deviation both in price and demand. The analysis for the load is based on load shedding and cycling values. We analyze the mean and standard deviation in market prices and we determine the price spike as a two sigma deviation from the mean value. It is shown that 60% of the price deviation ratios are in the range of ( +/- 20%), while 44% are in the range of ( +/- 10%) and 35% are in the range of (+/- 5%). We also show that 56.9% of the spikes are due to problems in the generation of natural gas based power plants which affect the day ahead and real time prices. A total of 29.2% of the spikes are due to power plant and system failures that affect only real time prices. The share of high temperature based spikes is 13.9% which is a result of air conditioner usage.
Citation Count: 87
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.
Citation Count: 1
An approach to evaluate CAM software alternatives
(TAYLOR & FRANCIS LTD, 2020) Ayağ, Zeki
The selection process for the best computer-aided manufacturing (CAM) software among a set of potential number of alternatives in market has been critical issue for most companies that aim to make their design/manufacturing-related activities automated. Because this selection process is very vital for companies because a wrong decision might put them into a difficult position in terms of economical, market share and time spent. Therefore, today's companies have used different multiple-criteria decision making (MCDM) methods for the evaluation study of CAM software alternatives to make this complex process easily applicable and not time-consuming. Among the MCDM methods in literature, the analytic hierarchy process (AHP) method has been widely used for various MCDM problems in both academic researches and industrial practices. However, in some cases, because of the vagueness and uncertainty on the judgments of decision maker(s), the crisp pair wise comparison in the conventional AHP seems to be insufficient and imprecise to capture the right judgments of decision maker(s). Therefore, a fuzzy logic method is integrated in the pair wise comparison of AHP to make up for this deficiency in the conventional AHP, called as fuzzy AHP. Moreover, the proposed approach is also realized on a case study.
Citation Count: 4
Are we at all liberal at heart? High-powered tests find no effect of intuitive thinking on moral foundations
(Academic Press Inc., 2021) Yılmaz, Onurcan
Two opposing views define the debate on the moral principles underlying human behavior. One side argues a central role for five moral foundations (care, fairness, loyalty, authority, sanctity), while the other argues that two of these (care, fairness) capture the essence of human moral concerns. In an experiment comparing these two views, Wright and Baril (2011) found that conservatives under cognitive load devalue loyalty, authority and sanctity, and become more liberal. Their finding of common intuitive concern with care and fairness supports the two-foundation perspective. In two high-powered preregistered experiments (N = 3275), we used time-pressure to induce intuitive thinking and tested Wright and Baril's finding that “we are all liberals at heart.” Although the manipulations worked as intended, Study 1 failed to identify an effect on the moral foundations questionnaire (MFQ). We conjectured that familiarity with standard survey items may weaken intuition manipulations by eliciting stable opinions. In Study 2, we therefore used not only the MFQ but also novel moral foundations vignettes. Study 2 failed to find an effect of time-pressure on either questionnaire type. An internal Bayesian meta-analysis indicated strong evidence against an effect of intuitive thinking on moral foundations.
Citation Count: 5
Art investment: hedging or safe haven through financial crises
(Springer, 2020) Öztürkkal, Belma; Toğan-Eğrican, Aslı
We analyze long-term art auction sales data focusing on and around financial crisis periods with other investment returns to understand whether art can be considered a safe haven during volatile times or a hedging option in general by analyzing art auction data in a volatile emerging market. Our findings suggest Turkish art returns are either negatively correlated or at low correlation with other investments, including the equity market. We have the view that art can be considered a hedging mechanism on average to enhance returns and to decrease the risk of portfolios and improve diversification. However, we do not discard the safe-haven hypothesis, either. Although the auction data on the crisis period is limited, results of and around crisis periods show art returns are positively correlated with various volatility indices. In addition, the number of art transactions also increases after the crisis years, which may be a sign of liquidity requirement of some investors and an opportunity for buyers. The benefit is visible especially during years of contractions, which do not end with a very severe crisis, since the art auction market liquidity dries if the crisis is severe.
Citation Count: 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 Count: 6
Attachment anxiety benefits from security priming: Evidence from working memory performance
(Public Library Science, 2018) Gökçe, Ahu; Harma, Mehmet
The present study investigates the relationship between the attachment dimensions (anxious vs. avoidance) and the cognitive performance of individuals specifically whether the attachment dimensions would predict the working memory (WM) performance. In the n-back task reflecting the WM capacity both attachment related and non-attachment related words were used. Participants were randomly assigned into two groups that received either the secure or the neutral subliminal priming. In the secure priming condition the aim was to induce sense of security by presenting secure attachment words prior to the n-back task performance. In neutral priming condition neutral words that did not elicit sense of security were presented. Structural equation modeling revealed divergent patterns for attachment anxiety and avoidance dimensions under the different priming conditions. In neutral priming condition WM performance declined in terms of capacity in the n-back task for individuals who rated higher levels of attachment anxiety. However in the secure priming condition WM performance was boosted in the n-back task for individuals who rated higher levels of attachment anxiety. In other words the subliminal priming of the security led to increased WM capacity of individuals who rated higher levels of attachment anxiety. This effect however was not observed for higher levels of attachment avoidance. Results are discussed along the lines of hyperactivation and deactivation strategies of the attachment system.
Citation Count: 19
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.
Citation Count: 0
Babbling through social media: A cross-country study mapping out social networks using eWOM intentions
(Springer, 2023) Zülal, İşler; Kıygı-Çallı, Meltem; El Oraiby, Maryam
This research aims to determine the factors affecting the users’ electronic word-of-mouth (eWOM) seeking and sharing intentions and to reveal the interactions among and within clusters using social network analysis (SNA). This study includes three hierarchical sub-studies conducted in two countries, Turkey and Poland. First, we develop a segmentation for social networking site (SNS) users based on the frequency of sharing product-related information on SNSs. Second, we investigate the impact of several factors that affect eWOM seeking and sharing intentions using regression analysis. In the second sub-study, we also include the identified segments developed in the first sub-study as another factor that may have differentiated eWOM intentions. Third, to understand the degree of interaction among SNS users, we apply an SNA using the forecasted eWOM intentions scores from the second sub-study, which gives us hypothetical social networks. The results of SNA present strong interactions inter- and intra-clusters in both countries. Some key findings include the identification of three SNS user segments, including “Middlers,” that may be of particular interest to brands. We also find that in terms of eWOM intentions, users in Turkey are more active than in Poland. Although some predictors of eWOM seeking and sharing intentions differ between the two countries, users intend to be more active in eWOM seeking than in eWOM sharing. The comparative study provides valuable insights for decision-makers to engage different market segments via SNSs with various proposed features using suggested information contents for selected product categories.
Citation Count: 22
Beyond Muslim identity: Opinion-based groups in the Gezi Park protest
(Sage Publications Ltd, 2017) Baysu, Gülseli; Phalet, Karen
Media depicted Turkish Gezi Park protests as a clash between secularists and Islamists within a majority-Muslim country. Extending a social identity approach to protests this study aims (a) to distinguish the protest participants in terms of their opinion-based group memberships (b) to investigate how their religious identification and their group membership were associated with democratic attitudes. Six hundred and fifty highly educated urban young adult participants were surveyed during the protest. Latent class analysis of participants' political concerns and online and offline actions yielded four distinct opinion-based groups labeled liberals secularists moderates and conservatives. Looking at the intersection of the participants' group identities with their Muslim identification we observed that the higher conservatives' and moderates' religious identification the less they endorsed democratic attitudes whereas religious identification made little or no difference in liberals' and secularists' democratic attitudes. Our findings of distinct groups among protest participants in a majority-Muslim country challenge an essentialist understanding of religion as a homogeneous social identity.
Citation Count: 3
The Black Sea Region: The Neighbourhood too Close to yet still Far from the European Union
(Routledge Journals Taylor & Francis Ltd, 2014) Acikmese Akgul, Sinem; Triantaphyllou, Dimitrios
[Abstract Not Available]

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