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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 Cooperative strategies, achievable rates and resource allocation for OFDMA channels(Işık Üniversitesi, 2011-07-28) Bakım, İsmail Sezi; Kaya, Onur; Işık Üniversitesi, Fen Bilimleri Enstitüsü, Elektronik Mühendisliği Doktora ProgramıThe design of next generation wireless communication systems brings along new challenges, since the degrading factors such as fading and multi-user interference become harder to deal with as the number of users and the bandwidth require- ments increase. Orthogonal Frequency Division Multiple Access (OFDMA) is a multiple accessing technique which provides a solution to both of the problems above: it provides a relatively simple way of assigning available bandwidth to users, while avoiding interference; and at the same time, it converts a frequency selective fading channel, to parallel flat fading subchannels, hence reducing the effects of intersymbol interference. However, in wireless channels, what is tradi- tionally considered as interference is in fact side information, and combined with the diversity created by the orthogonal subchannels in OFDMA, this side infor»mation can be carefully taken advantage of to increase the rates achievable by the users. In our thesis, without imposing any prior constraints on subchannel allocation, we investigate cooperation strategies, achievable rates and resource allocation for OFDMA channels. We propose new cooperative encoding strategies for wireless communication net- works över OFDMA channels. We particularly focus on a two user cooperative OFDMA system, based on block Markov superposition encoding (BMSE). We obtain expressions of the resulting achievable rate regions for ali proposed coroperative encoding strategies. We show that, by allowing for re-partitioning and re-encoding of the cooperative messages across subchannels, it is possible to better exploit the diversity created by OFDMA, and higher rates can be achieved. In order to take full advantage of the diversity created by OFDMA, we then introduce a channel adaptive cooperation strategy for OFDMA, and optimize the transmit powers as a function of the channel states. We provide the optimality conditions that need to be satisfied by the powers associated with the users' codewords and derive the closed form expressions for the optimal powers.Yayın Positive solutions for a sum-type singular fractional integro-differential equation with m-point boundary conditions(Politechnica University of Bucharest, 2017) Aydoğan, Seher Melike; Nazemi, Sayyedeh Zahra; Rezapour, ShahramWe study the existence and uniqueness of positive solutions for a sum-type singular fractional integro-differential equation with m-point boundary condition. Also, we provide an example to illustrate our main result.Yayın EOQ model with transportation cost under deterministic demand(Işık Üniversitesi, 2012-12-24) Kars, Cihan; Altunbay, Seyhun; Işık Üniversitesi, Fen Bilimleri Enstitüsü, Endüstri Mühendisliği - Yöneylem Araştırması Yüksek Lisans ProgramıInventory planning issues are one of the most important aspects of the companies. To have optimal stock level both for production planning and low stock holding cost with successful demand forecast is also very important. If the companies work with high stock level, it causes the increase of the unused capital and it hinders to use the money for more effective operations. In global world, the companies purchase goods, semi-finished goods or materials from different regions of the world. They purchase the goods with variable quantities from different regions and directly affect the stock level of the companies. Furthermore it is essential to take transportation cost into account with the consumption quantity of material and the purchase price of unit material while determining inventory stock levels. There are also different payment options in purchasing of materials. The cash payment or the payment after receiving goods have also role in determining stock levels. When we take into account the transportation options and the payment options of purchasing materials the classical economic order quantity model is inadequate. The aim of this thesis is to have a new approach of economic order quantity model by considering the transportation cost and different payment options when we have deterministic demand. By the calculation of all possible transportation and payment alternatives, it becomes possible to find the optimum options of transportation and payment. The new model was implemented for a specific material of company X, for deterministic demand and the aim is to have optimal stock level for the specific material. The program MINITAB is used to find the appropriate method among different forecasting methods. The consumption of specific materials is evaluated and a sample group is composed to implement the new model. The all possible transportation modes, transportation durations and the historical demand data of 2010 and 2011 are collected and analyzed. Demand forecasting methods are applied on historical demand data and the results are accepted as deterministic and transportation modes and times are investigated in excel and used in problem. The process of the model is shown for the material WTR910R and the results are compared with the old system of company X.Yayın CSR practices in Turkey: Examining CSR reports(Greenleaf Publishing, 2015-07) Uyan Atay, Bilge; Tuncay Çelikel, AslıThis study examines the private companies that publish CSR reports in Turkey. Turkey has a growing economy, located in an international arena with an increasing number of global brands starting to export their products from Turkey with even more multinational enterprises (MNEs) planning to locate in the country. Now, some Turkish companies and subsidiaries of MNEs have started to publish CSR reports. Our findings show that strong Turkish conglomerates are playing a constructive role in macro-level development and governance in Turkey. They are also addressing local problems such as education, human rights, environmental protection and workers' rights. Besides, subsidiaries of MNEs are also having an impact with respect to the application of their headquarters' community programs in Turkish society.Yayın Turkey's Kurdish opening: Long awaited achievements and failed expectations(Routledge Journals, 2014-01-02) Kayhan Pusane, ÖzlemTurkish state actors have used mainly military means to first suppress the Kurdish rebellions and then to end the PKK violence from 1984 onwards. However, after the AKP came to office in 2002, the government challenged the hardline state policy and initiated a Kurdish opening. This policy has the ultimate goal of disarming the PKK and resolving the Kurdish question. However, the Kurdish opening so far has failed to bring about the desired policy outcomes because the parties to the Kurdish question have been highly divided on the side of both the state and the Kurds in Turkey.Yayın Cognitive cooperative MAC with one primary and two secondary users: achievable rates and optimal power control(IEEE-INST Electrical Electronics Engineers Inc, 2014-11) Edemen, Çağatay; Kaya, OnurWe consider a three-user fading cognitive cooperative multiple access channel (MAC) with one primary and two secondary transmitters. We propose two encoding/decoding strategies with varying levels of cooperation, based on block Markov superposition encoding and backward decoding. The first is an overlay model, where the secondary users (SUs) aid the transmission of the primary user (PU) by causally decoding the PU message and forwarding it while also cooperating among each other. The second is an underlay model, where the SUs cooperate by decoding and forwarding each other's messages while treating the signal received from the PU as noise. In either case, the PU is guaranteed to operate at its maximum achievable single user rate. We characterize the achievable SU rate region for both models and maximize this region as a function of the transmit powers. The simulation results show that the SU rate region can be significantly enlarged, particularly using the overlay model.Yayın Author identification of newspaper columns using style and semantic features(Işık Üniversitesi, 2016-05-17) Yıldız, Ergin Doğan; Solak, Ercan; Işık Üniversitesi, Fen Bilimleri Enstitüsü, Bilgisayar Mühendisliği Yüksek Lisans ProgramıThis study has two major purposes : to implement and compare the author classification results of di erent Naive Bayes Classi ers, and to investigate whether merging individual methods will increase classi cation success or not. The subjects of this study were newspaper columnists. Data was collected from well known public newspapers. This study first investigates Numeric, Nominal, Multinominal NBC, and their various merged versions. We then address each method using cross-validation. The results of the experiments show that merging multiple classi cation methods can increase classifi cation success. Additionally, it depends on how well individual classifi cation models are constructed.Yayın Equilibrium and stability analysis of delayed neural networks under parameter uncertainties(Elsevier Science Inc, 2012-02-15) Faydasıçok, Özlem; Arik, SabriThis paper proposes new results for the existence, uniqueness and global asymptotic stability of the equilibrium point for neural networks with multiple time delays under parameter uncertainties. By using Lyapunov stability theorem and applying homeomorphism mapping theorem, new delay-independent stability criteria are obtained. The obtained results are in terms of network parameters of the neural system only and therefore they can be easily checked. We also present some illustrative numerical examples to demonstrate that our result are new and improve corresponding results derived in the previous literature.Yayın An inverse source problem connected thermoacoustic imaging in multi-layer planar medium(Işık Üniversitesi, 2018-06-04) Yücel, Hazel; Uzun, Banu; Işık Üniversitesi, Fen Bilimleri Enstitüsü, Matematik Doktora ProgramıIn this thesis, we mentioned imaging technics used today, and microwave induced thermoacoustic procedure and imaging. We made literature survey about solution of the thermoacoustic equation for homogeneous and inhomogeneous medium. We modelled the inhomogenity of medium as a multi-layer planar structure and de?ned initial condition, continuity conditions on the layer boundaries and radiation conditions at in?nity, then we derived analytical forward and inverse solution of the thermoacoustic wave equation for inhomogeneous medium with the source distribution existing in all layers. Our solution of inverse source problem is based on the methods of the Green’s functions for layered planar media. For qualitative testing and comparison of the point-spread functions associated with the conventional solution for homogeneous medium and our derived layered solutions, we performed numerical simulations. In numerical simulations ?rst we generated the measured data by using the derived forward solution for multi-layer planar medium and then we used conventional inverse solution and our derived inverse solution to image source distribution. Our simulation results showed that the conventional inverse solution based on homogeneous medium assumption, as expected, produced incorrect locations of point sources, whereas our inverse solution involving the multi-layer planar medium produced point sources at the correct source locations. Also, we showed that the performance of layered inverse solution is sensitive to the validity of the layer parameters and medium parameters used as prior information in the measured data. Our inverse solutions based on multi-layer planar media are applicable for cross-sectional 2 dimensional imaging of the organs such as breast, skin, and abdominal structure.
