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Article Citation - WoS: 31Citation - Scopus: 42Acculturation Attitudes and Social Adjustment in British South Asian Children: a Longitudinal Study(Sage Publications Inc, 2013) Brown, Rupert; Baysu, Gülseli; Cameron, Lindsey; Nigbur, Dennis; Rutland, Adam; Watters, Charles; Hossain, Rosa; LeTouze, Dominique; Landau, AnickA 1-year longitudinal study with three testing points was conducted with 215 British Asian children aged 5 to 11 years to test hypotheses from Berry's acculturation framework. Using age-appropriate measures of acculturation attitudes and psychosocial outcomes it was found that (a) children generally favored an integrationist attitude and this was more pronounced among older (8-10 years) than in younger (5-7 years) children and (b) temporal changes in social self-esteem and peer acceptance were associated with different acculturation attitudes held initially as shown by latent growth curve analyses. However a supplementary time-lagged regression analysis revealed that children's earlier integrationist attitudes may be associated with more emotional symptoms (based on teachers' ratings) 6 months later. The implications of these different outcomes of children's acculturation attitudes are discussed.Article Citation - WoS: 3Citation - Scopus: 5Activist Communication Design on Social Media: the Case of Online Solidarity Against Forced Islamic Lifestyle(Sage Publications, 2021) Arda Güney, Talat Balca; Akdemir, AyşegülThis article explores the relationship between connective and collective group identity through the example of “You Won’t Walk Alone,” a social media platform of solidarity for women suffering from the pressures of Islamic dress code in Turkey. While Turkey has a long history of conservative women’s initiatives against secular institutional code and of secular women against Islamic and misogynist social reactions, the social media platform You Won’t Walk Alone (Yalnız Yürümeyeceksin) illustrates a striking self-reflexivity of women mobilizing against their very own conservative communities. The research is based on multimodal content analysis of the posts including both images and texts in order to grasp to what extent social media offers a genuine public space for anonymous participants of the online platform as opposed to digitally networked movements which primarily reflect personalized agency. We analyze how connective and collective group identity can be correlated in this case in which online participants build solidarity by sharing content anonymously. Hence, this article questions the ways in which activist design of communication affects and shapes activism through this case study.Article Citation - WoS: 6Citation - Scopus: 10An Adaptive Affinity Matrix Optimization for Locality Preserving Projection Via Heuristic Methods for Hyperspectral Image Analysis(IEEE-Inst Electrıcal Electronıcs Engıneers Inc, 2019) Taşkın, Gülşen; Ceylan, OğuzhanLocality 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.Article Citation - WoS: 21Citation - Scopus: 31Adoption of Mobile Health Apps in Dietetic Practice: Case Study of Diyetkolik(Jmır Publıcatıons, Inc, 130 Queens Quay E, 2020) Akdur, Görkem; Aydın, Mehmet Nafiz; Akdur, GizdemBackground: Dietetics mobile health apps provide lifestyle tracking and support on demand. Mobile health has become a new trend for health service providers through which they have been shifting their services from clinical consultations to online apps. These apps usually offer basic features at no cost and charge a premium for advanced features. Although diet apps are now more common and have a larger user base, in general, there is a gap in literature addressing why users intend to use diet apps. We used Diyetkolik, Turkey's most widely used online dietetics platform for 7 years, as a case study to understand the behavioral intentions of users. Objective: The aim of this study was to investigate the factors that influence the behavioral intentions of users to adopt and use mobile health apps. We used the Technology Acceptance Model and extended it by exploring other factors such as price-value, perceived risk, and trust factors in order to assess the technology acceptance of users. Methods: We conducted quantitative research on the Diyetkolik app users by using random sampling. Valid data samples gathered from 658 app users were analyzed statistically by applying structural equation modeling. Results: Statistical findings suggested that perceived usefulness (P<.001), perceived ease of use (P<.001), trust (P<.001), and price-value (P<.001) had significant relationships with behavioral intention to use. However, no relationship between perceived risk and behavioral intention was found (P=.99). Additionally, there was no statistical significance for age (P=.09), gender (P=.98), or previous app use experience (P=.14) on the intention to use the app. Conclusions: This research is an invaluable addition to Technology Acceptance Model literature. The results indicated that 2 external factors (trust and price-value) in addition to Technology Acceptance Model factors showed statistical relevance with behavioral intention to use and improved our understanding of user acceptance of a mobile health app. The third external factor (perceived risk) did not show any statistical relevance regarding behavioral intention to use. Most users of the Diyetkolik dietetics app were hesitant in purchasing dietitian services online. Users should be frequently reassured about the security of the platform and the authenticity of the platform's dietitians to ensure that users' interactions with the dietitians are based on trust for the platform and the brand.Article Citation - WoS: 41Citation - Scopus: 50Alevis 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, ŞuleThe 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.Article Citation - WoS: 17Citation - Scopus: 20All the Dark Triad and Some of the Big Five Traits Are Visible in the Face(Pergamon-Elsevıer Scıence Ltd, 2021) Alper, Sinan; Bayrak, Fatih; Yılmaz, OnurcanSome 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.Article Citation - WoS: 6Citation - Scopus: 6Alone but Together Autonomous but Related: Self-Construal Effects on Happiness in Social Experiences(Wiley, 2018) Merdin-Uygur, Ezgi; Hesapci, OzlemCommunal tables and open workspaces have become popular servicescapes that is contemporary spaces for experiencing dining or working alone but together. Previous research demonstrates that experiencing with close others (e.g. with friends or family) increases happiness and satisfaction but experiences shared with strangers in contexts such as communal tables or workshops have not yet been thoroughly analyzed. Addressing this research gap from a social-psychological perspective we suggest that even though individuals are generally happier when they share experiences with loved ones self-construal plays a moderating role in the relationship. Individuals with high autonomy and high relatedness do not anticipate greater happiness from experiences shared with friends than with those shared with strangers. Three experimental studies (two online and one field) demonstrate this effect using different operationalizations of autonomy relatedness. Managerial implications are discussed and suggestions are made for future research.Book Review The American Passport in Turkey: National Citizenship in the Age of Transnationalism(Routledge Journals, Taylor & Francıs Ltd, 2020) Yanardağoğlu, Eylem[Abstract Not Available]Article Citation - WoS: 5Citation - Scopus: 5Analysis of Mixed-Element Structures Formed With Shunt Capacitors Separated by Transmission Lines(IEEE-Inst Electrical Electronics Engineers Inc, 2019) Şengül, Metin Y.; Çakmak, GökhanIn 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.Article Citation - WoS: 7Citation - Scopus: 12An Analysis of Price Spikes and Deviations in the Deregulated Turkish Power Market(Elsevier, 2019) Gayretli, Gizem; Yücekaya, Ahmet; Bilge, Ayşe HümeyraThe 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.Article Analytic Solution of the Feldtkeller Equation(Elsevier GMBH Urban & Fischer Verlag, 2009) Şengül, Metin Y.In every reflectance-based application like broadband matching circuit modeling etc. a nonlinear equation following from energy conservation the Feldtkeller equation must be solved in order to obtain real networks. In the literature however there is no analytic solution available but only numerical solutions. Consequently the resulting error depends on the accuracy of the numerical tools. In this paper an analytic solution is proposed which is based on the modified ABCD-parameters of a lossless reciprocal two-port network. An algorithm is presented and examples are included to illustrate the implementation of the analytical method. (C) 2008 Elsevier GmbH. All rights reserved.Article Citation - WoS: 33Citation - Scopus: 37Antecedents and Performance Outcomes of Value-Based Selling in Sales Teams: a Multilevel, Systems Theory of Motivation Perspective(Springer, 2020) Mullins, Ryan; Mengüç, Bülent; Panagopoulos, Nikolaos G.Firms are increasingly deploying a value-based selling (VBS) approach in their sales organizations to drive growth for new offerings. However, VBS adoption remains challenging, signaling that leaders need guidance to motivate VBS. Drawing from the systems theory of motivation, we examine motivational mechanisms at two levels-salesperson and sales team-to understand how to motivate, and benefit from, VBS. Using multisource data (i.e., salespeople, managers, archival performance) from 70 sales teams in a U.S.-based manufacturing and services provider, our findings illustrate drivers and outcomes of VBS. Specifically, we uncover a framework of salesperson, leader, customer, and team factors that help explain salesperson motivation for VBS. Importantly, we link VBS to customers' adoption of new products to support VBS's role for selling new products. Critical for sales team strategy, our model also integrates a team-level motivational mechanism to provide a comprehensive framework for salesperson and sales team motivations and outcomes.Article Citation - WoS: 18Citation - Scopus: 23Applying a Behavioural and Operational Diagnostic Typology of Competitive Intelligence Practice: Empirical Evidence From the Sme Sector in Turkey(Taylor and Francis Group, 2012) Wright, Sheila; Bisson, Christophe; Duffy, Alistair P.This paper reports on an empirical study conducted within the SME sector in the city of Istanbul Turkey. The findings from this study enabled the creation of a behavioural and operational typology of competitive intelligence practice one developed from the work of S. Wright D.W. Pickton and J. Callow (2002. Competitive intelligence in UK firms: A typology. Marketing Intelligence & Planning 20 349-360). Using responses to questions which indicated a type of behaviour or operational stance towards the various strands of CI practice under review it has been possible to identify areas where improvements could be made to reach an ideal situation which could garner significant competitive advantage for the SMEs surveyed. © 2012 Copyright Taylor and Francis Group LLC.Article Citation - WoS: 1Citation - Scopus: 3An Approach To Evaluate Cam Software Alternatives(TAYLOR & FRANCIS LTD, 2020) Ayağ, ZekiThe 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.Article Citation - WoS: 6Citation - Scopus: 7Are We at All Liberal at Heart? High-Powered Tests Find No Effect of Intuitive Thinking on Moral Foundations(Academic Press Inc., 2021) Yılmaz, Onurcan;İşler, Ozan;Doğruyol, BurakTwo 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.Article Citation - WoS: 9Citation - Scopus: 9Art Investment: Hedging or Safe Haven Through Financial Crises(Springer, 2020) Öztürkkal, Belma; Toğan-Eğrican, AslıWe 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.Article Citation - WoS: 55Citation - Scopus: 78Assessing the Importance of International Tourism for the Turkish Economy: a Social Accounting Matrix Analysis(Elsevier Science, 2012) Akkemik, K. Ali; Akkemik, K. AliThe international tourism sector has grown rapidly in Turkey since the 1980s and Turkey ranks among the top ten countries in terms of tourist arrivals and receipts. Previous studies on international tourism in Turkey are partial equilibrium studies which emphasized the importance of the sector for foreign exchange earnings employment creation and economic growth. The social accounting matrix (SAM) modeling approach is superior to partial equilibrium analysis as it takes into account intersectoral linkages. This paper analyzes the contribution of international tourism to the Turkish economy using two SAMs for 1996 and 2002 respectively. Two analyses are conducted using the SAM impact model: (i) sectoral comparison of GDP elasticities and (ii) SAM impact analysis of international tourism on output value-added and employment. The results show that the GDP elasticity of international tourism is relatively low and the impact of foreign tourist expenditures on domestic production value-added (GDP) and employment in Turkey are modest. The results imply the possibility of leakage of foreign tourist expenditures out of the economy. (C) 2011 Elsevier Ltd. All rights reserved.Article Citation - WoS: 12Citation - Scopus: 12Assessment of Chromite Liberation Spectrum on Microscopic Images by Means of a Supervised Image Classification(Elsevier Science Bv, 2017) Camalan, Mahmut; Çavur, Mahmut; Hosten, CetinAssessment of mineral liberation spectrum with all its aspects is essential for plant control and optimization. This paper aims to estimate 2D mineral map and its associated liberation spectrum of a particular chromite sample from optical micrographs by using Random Forest Classification a powerful machine-learning algorithm implemented on a user-friendly and an open-source software. This supervised classification method can be used to accurately generate 2D mineral map of this chromite sample. The variation of the measured spectra with the sample size is studied showing that images of 200 particles randomly selected from the optical micrographs are sufficient to reproduce liberation spectrum of this sample. In addition the 2D spectrum obtained with this classification method is compared with the one obtained from the Mineral Liberation Analyzer (MLA). Although 2D mineralogical compositions obtained by the two methods are quite similar microscopic analysis estimates poorer liberation than MLA due to the residual noise (misclassified gangue) generated by the classification. Nevertheless we cannot compare the reliabilities of the two methods as there is not a standard produce yet to quantify the accuracy of MLA analysis. (C) 2017 Elsevier B.V. All rights reserved.Article Citation - WoS: 4Citation - Scopus: 4An Assessment of Mining Efficiency in Turkish Lignite Industry(Elsevier Science, 2015) Ediger, Volkan S.; Berk, Istemi; Ersoy, MucellaThis article focuses on the mining activities of Turkish Coal Enterprises (TKI) the major lignite supplier in Turkey. First we analyzed the lignite production and overburden removal activities of TKI from a historical perspective and then employed the Principle Component Analysis to build a mining efficiency index of TKI and investigated its historical development since the establishment of the company. We found that labor productivity and operational structure have been the most important factors positively affecting the index. The current article makes two important contributions: (1) by using the most comprehensive data set available on TKI for the first time and (2) by developing a Mining Efficiency Index (MEI) which can be used to analyze productivity in lignite mining activities in different countries. (C) 2015 Elsevier Ltd. All rights reserved.Article Citation - WoS: 6Citation - Scopus: 7Assortment Optimization With Log-Linear Demand: Application at a Turkish Grocery Store(Elsevier, 2019) Hekimoğlu, Mustafa; Sevim, İsmail; Aksezer, Çağlar Sezgin; Durmuş, İpekIn retail sector product variety increases faster than shelf spaces of retail stores where goods are presented to consumers. Hence assortment planning is an important task for sustained financial success of a retailer in a competitive business environment. In this study we consider the assortment planning problem of a retailer in Turkey. Using empirical point-of-sale data a demand model is developed and utilized in the optimization model. Due to nonlinear nature of the model and integrality constraint we find that it is difficult to obtain a solution even for moderately large product sets. We propose a greedy heuristic approach that generates better results than the mixed integer nonlinear programming in a reasonably shorter period of time for medium and large problem sizes. We also proved that our method has a worst-case time complexity of O(n 2 )while other two well-known heuristics’ complexities are O(n 3 )and O(n 4 ). Also numerical experiments reveal that our method has a better performance than the worst-case as it generates better results in a much shorter run-times compared to other methods. © 2019 Elsevier Ltd
