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Yayın Are your cross-ethnic friends ethnic and/or national group identifiers?The role of own and perceived cross-ethnic friend's identities on outgroup attitudes and multiculturalism(Wiley, 2018-02-01) Bağcı Hemşinlioğlu, Sabahat Çiğdem; Çelebi, ElifWe investigated how own ethnic and national identities and perceived ethnic and national identities of close cross-ethnic friends may predict outgroup attitudes and multiculturalism among Turkish (majority status, N=197) and Kurdish (minority status, N=80) ethnic group members in Turkey (M-age=21.12, SD=2.59, 69.7% females, 30.3% males). Compared with Turkish participants, Kurdish participants were more asymmetrical in rating their cross-ethnic friend's identities relative to their own, reporting higher ethnic identity, but lower national identity for themselves. Own ethnic identity was negatively associated with attitudes and multiculturalism, whereas own national identity was positively associated with only attitudes. Perceived cross-ethnic friend's national identity was positively related to both outgroup attitudes and multiculturalism. Shared national identification (high levels of own and friend's national identity) led to most positive outgroup attitudes and highest support for multiculturalism. Findings were discussed in the light of social identity and common ingroup identity models.Yayın Assortment optimization with log-linear demand: application at a Turkish grocery store(Elsevier Ltd, 2019-09) Hekimoğlu, Mustafa; Sevim, İsmail; Aksezer, Sezgin Çağlar; 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.Yayın A new method for the source localization in sectionally homogeneous bounded domains involving finitely many inner interfaces of arbitrary shapes(Pergamon-Elsevier Science, 2001-05) İdemen, Mehmet Mithat; Alkumru, AliA new method to localize a static point source buried in a nonhomogeneous bounded domain composed of finitely many homogeneous parts separated by interfaces of arbitrary shapes was established. The source can be a simple point charge or current or a dipole of them. The method requires only the knowledge of the potential function Phi (x, y, z) at five or six points on the outermost interface depending on whether the source is simple or dipole. The new and basic feature of the method consists of determining the potential function Phi (0)(x, y, z) which would be observed if the whole space was filled with a homogeneous material. Then, in the case of a simple source, the position P-0 as well as the strengths can be determined, in general, by solving a system of three linear algebraic equations. When the source consists of a dipole, its position P-0 and moment (p) over right arrow can be found by solving a system of six nonlinear algebraic equations. The determination of Phi (0) P-0 and s (or (p) over right arrow) is achieved iteratively by solving the above-mentioned algebraic equations along with a singular integral equation satisfied by Phi (0) Some illustrative examples show the applicability and accuracy of the method. The method can have effective applications in heat conduction, matter diffusion, electrostatics, steady-state current flow, electroencephalography, electrocardiography, etc.Yayın Sustainability via extended warranty contracts: design for a consumer electronics retailer(MDPI, 2024-01) Aksezer, Sezgin ÇağlarWarranty is one of the most important attributes of any product, from both manufacturer and consumer points of view. Although the retailers connect manufacturers to customers by selling goods, traditionally, they have isolated themselves from warranty-related matters such as customer complaints and maintenance costs. However, recent trends in consumer behavior toward extended warranty contracts have changed this approach. While retailers have started to generate considerable revenue from the sale of these contracts, sustainability is also achieved by longer product life cycles. This study analyzed the failure behavior of different classes of cell phone products and their related costs through a chain of consumer electronics retailer operating in Türkiye. To compete on pricing and customer service, a novel policy was designed for the retailer to honor the contracts in house rather than underwriting to a third party insurer as the industry standard. The maintenance records of 328 previous failures were analyzed to plot a failure model. Failure mode and effects analysis was carried out to identify failure classes and the respective costs for extended warranty design for cell phones. The expected warranty costs for coverage of the third, fourth, and fifth years of operation were determined. The results show that the retailer may achieve the same level of profit by increasing customer satisfaction along with the sustainability of the product through repair actions.Yayın The function of regressions in reading: Backward eye movements allow rereading(Springer, 2013-01) Booth, Robert William; Weger, Ulrich W.Standard text reading involves frequent eye movements that go against normal reading order. The function of these "regressions" is still largely unknown. The most obvious explanation is that regressions allow for the rereading of previously fixated words. Alternatively, physically returning the eyes to a word's location could cue the reader's memory for that word, effectively aiding the comprehension process via location priming (the "deictic pointer hypothesis"). In Experiment 1, regression frequency was reduced when readers knew that information was no longer available for rereading. In Experiment 2, readers listened to auditorily presented text while moving their eyes across visual placeholders on the screen. Here, rereading was impossible, but deictic pointers remained available, yet the readers did not make targeted regressions in this experiment. In Experiment 3, target words in normal sentences were changed after reading. Where the eyes later regressed to these words, participants generally remained unaware of the change, and their answers to comprehension questions indicated that the new meaning of the changed word was what determined their sentence representations. These results suggest that readers use regressions to reread words and not to cue their memory for previously read words.Yayın Does everyone benefit equally from self-efficacy beliefs? The moderating role of perceived social support on motivation(Sage Publications Inc, 2018-02) Bağcı Hemşinlioğlu, Sabahat ÇiğdemThis study investigated whether perceived goal support from family and friends may moderate the relationship between academic self-efficacy and motivational outcomes among early adolescent students recruited from a low-middle socio-economic status(SES) background school in Turkey (N = 319, Xa(ge) = 13.13, SD = .80). Self-report questionnaires included measures of academic self-efficacy, perceived family and friend support, and academic and career motivations. Academic self-efficacy and perceived support from family related positively to both types of motivation. Children who perceived lower family support benefited more from the positive effects of self-efficacy on motivations, whereas children with higher family support seemed to gain less (or not gain at all) from self-enhancing functions of self-efficacy. Same findings were found for peer support, but only when family support was excluded from analyses. Findings implied the need to study larger family and peer contexts under which self-efficacy beliefs may be more or less effective on motivation.Yayın Evolutionary route to diploidy and sex(National Academy of Sciences, 2001-11-20) Tüzel, Erkan; Sevim, Volkan; Erzan, AyşeBy using a bit-string model of evolution, we find a successful route to diploidy and sex in simple organisms. Allowing the sexually reproducing diploid individuals to also perform mitosis, as they do in a haploid-diploid cycle, leads to the complete takeover of the population by sexual diploids. This mechanism is so robust that even the accidental conversion and pairing of only two diploids give rise to a sexual population.Yayın Synergistic effect of the locust bean gum on the thermal phase transitions of kappa-carrageenan gels(Elsevier Sci Ltd, 2009-03) Arda, Ertan; Kara, Selim; Pekcan, Mehmet ÖnderSynergism between K-carrageenan and locust bean gum (LBG) was studied using the photon transmission technique. Synergistic effects in these polymeric mixtures strongly affected the physical properties of the gel structure. The transmitted light intensities, I-tr, versus temperature variations were investigated during the gelation and liquefaction processes. Slight synergistic peaks were detected in gel-sol and sol-gel transition temperatures for high kappa-carrageenan/LBG ratios (approx. 80/2). Moreover, apparent synergistic peaks were observed in gel-sol and sol-gel transition activation energies for the mixtures approximately with the ratios of 80/10.Yayın Future projections of temperature and precipitation climatology for CORDEX-MENA domain using RegCM4.4(Elsevier Science Inc, 2018-07-01) Öztürk, Tuğba; Turp, Mustafa Tufan; Türkeş, Murat; Kurnaz, Mehmet LeventIn this study, we investigate changes in seasonal temperature and precipitation climatology of CORDEX Middle East and North Africa (MENA) region for three periods of 2010-2040, 2040-2070 and 2070-2100 with respect to the control period of 1970-2000 by using regional climate model simulations. Projections of future climate conditions are modeled by forcing Regional Climate Model, RegCM4.4 of the International Centre for Theoretical Physics (ICTP) with two different CMIP5 global climate models. HadGEM2-ES global climate model of the Met Office Hadley Centre and MPI-ESM-MR global climate model of the Max Planck Institute for Meteorology were used to generate 50 km resolution data for the Coordinated Regional Climate Downscaling Experiment (CORDEX) Region 13. We test the seasonal time-scale performance of RegCM4.4 in simulating the observed climatology over domain of the MENA by using the output of two different global climate models. The projection results show relatively high increase of average temperatures from 3 degrees C up to 9 degrees C over the domain for far future (2070-2100). A strong decrease in precipitation is projected in almost all parts of the domain according to the output of the regional model forced by scenario outputs of two global models. Therefore, warmer and drier than present climate conditions are projected to occur more intensely over the CORDEX-MENA domain.Yayın On the performance of West's bubble test: A simulation approach(Elsevier science inc, 2010-12-01) Yüksel, Sadettin Aydın; Akdeniz, Levent; Altay Salih, AslıhanIn this research we examine the ability of West's bubble test [1] in detecting speculative bubbles using Brock's (1982) [2] intertemporal general equilibrium model of asset pricing as the basis for a simulation study. In this setting, (1) the economy, by construction is efficient and produces the maximally possible amount of welfare for society, and (2) asset prices reflect the utility-maximizing behavior of consumers and the profit-maximizing behavior of firms. We find that the West's bubble test flag as "bubbles" in the simulated data yet the data is produced from an economy in which markets are efficient in welfare production.
