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Listeleniyor 1 - 10 / 184
  • 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, Elif
    We 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
    Turkey's Kurdish opening: Long awaited achievements and failed expectations
    (Routledge Journals, 2014-01-02) Kayhan Pusane, Özlem
    Turkish 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, Onur
    We 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
    Generic BER analysis of VLC channels impaired by 3D user-mobility and imperfect CSI
    (Institute of Electrical and Electronics Engineers Inc., 2021-07) Reddy Sekhar, K.; Miramirkhani, Farshad; Mitra, Rangeet; Turlapaty, Anish Chand
    Visible light communications (VLC) has emerged as a high-speed, low-cost, and green supplement for the existing radio frequency (RF) based infrastructures. However, the performance of VLC based systems is found to degrade significantly due to detrimental outages caused by non-negligible variations in the VLC channel-gain, that are jointly induced by radial user-mobility and random photodetector-orientation (together designated as 3D mobility in this letter). In addition to the 3D user-mobility mentioned above, the performance of VLC based systems is further limited by imperfect channel-state information (CSI). Such degradations in the VLC-link caused by the aforementioned factors necessitate the quantification of performance-metrics for further benchmarking/receiver-design. In this work, an analytical expression for bit-error rate (BER) is derived for a single LED indoor VLC system considering the radial user-mobility, random receiver orientation, and imperfect CSI altogether. Further, the derived BER expressions are validated using computer-simulations using typical VLC channel models from the literature. A close agreement between the analytical and the simulated BER is observed, which verifies the accuracy of the presented analysis.
  • Yayın
    A gain-switched self-optimizer for braking controller
    (John Wiley and Sons Ltd, 2017-06) Dinçmen, Erkin
    An emergency braking controller is developed with improved operation characteristics near the maximum friction zone. The methodology is based on self-seeking a-priori unknown optimum operation point to maximize a performance function representing the optimal behavior of the considered dynamic system. Sliding mode with uncertain direction of control vector approach is utilized in the algorithm. An adaptive variable gain is utilized in the algorithm to improve its performance. Via the variable gain, both fast convergence to the a-priori unknown optimum operation point and reduced magnitude of oscillations in the braking moment inputs resulting less aggressive control action are achieved.
  • Yayın
    Unnecessary bleeding, unnecessary suffering: normalcy and necessity of menstruation in promoting NovaSure (R)
    (Routledge, 2016-08) Erol Jamieson, Maral
    NovaSure (R) is an endometrial ablation procedure that destroys the inner lining of uterus to stop heavy bleeding. It is performed mostly on women entering menopause who are experiencing irregular and heavy bleeding. In this article, this biotechnology, promoted for women approaching the end of their reproductive life, is analyzed. The analysis is informed by a feminist science studies and medical anthropology background. The discourse of normal' menstruation and representations of menstruation in the promotional materials for NovaSure (R) are explored through a textual analysis of the NovaSure (R) website and patient brochure. The themes in the materials analyzed include the idea of getting back to life, normal' bleeding, and having a choice among different medical procedures and interventions. The possibility of getting rid of embarrassment that accompanies heavy bleeding is also emphasized. It will be argued that NovaSure (R) contributes to the redefinition of what is natural' and necessary' by combining the unnecessary period' idea of pills such as Seasonale (R), which is aimed toward women in their reproductive years, with the unnecessary suffering' idea related to menopausal complaints. While advertising the procedure, NovaSure (R) promotional materials co-construct the ideal user for the technology and reproduce the taboos and embarrassment that accompany menstruation.
  • Yayın
    The relationship between a mother's attitude toward domestic violence and children's schooling outcomes in Turkey
    (Sage Publications Inc, 2014-09) Rende, Sevinç
    This study explores the relationship between a mother's attitude toward domestic violence and her children's schooling outcomes in Turkey. The sample is drawn from the 2003 Turkish Demographic and Health Survey and consists of 7,951 children within the ages of legally mandated compulsory education. A probit regression model is used to analyze the data. The results suggest that the daughters of mothers who find domestic violence acceptable are 2.6 percentage point less likely to enroll in school, all else being equal, than the daughters of mothers who do not tolerate abuse. In comparison, the schooling outcomes of male children are not statistically sensitive to the mother's attitude toward wife beating. The policy implications of the results are discussed.
  • Yayın
    A new robust stability criterion for dynamical neural networks with multiple time delays
    (Elsevier Science BV, 2013-01-01) Faydasıçok, Özlem; Arik, Sabri
    This paper investigates the problem of the existence, uniqueness and global asymptotic stability of the equilibrium point for the class of neural networks with multiple time delays and parameter uncertainties. Under the assumption that the activation functions are globally Lipschitz continuous, we derive a new criterion for the robust stability of a class of delayed neural networks by utilizing the Lyapunov stability theorems and the Homomorphic mapping theorem. Different from those previously published conditions in the recent literature, the robust stability result presented in this paper not only establishes a time-independent relationship between the network parameters of the neural network, but also takes into account the number the neurons of the designed neural system. Some illustrative numerical examples are also given to make a detailed comparison between our result and the previously published corresponding results. This comparison proves that our result is new and can be considered an alternative condition to those of the previously reported robust stability results.
  • Yayın
    Sustainability via extended warranty contracts: design for a consumer electronics retailer
    (MDPI, 2024-01) Aksezer, Sezgin Çağlar
    Warranty 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
    Waves in an elastic tube filled with a heterogeneous fluid of variable viscosity
    (Pergamon-Elsevier Science Ltd, 2009-07) Demiray, Hilmi
    By treating the artery as a prestressed thin elastic tube and the blood as an incompressible heterogeneous fluid with variable viscosity. we studied the propagation of weakly non-linear waves in such a composite medium through the use of reductive perturbation method. By assuming a variable density and a variable viscosity for blood in the radial direction we obtained the perturbed Korteweg-deVries equation as the evolution equation when the viscosity is of order of epsilon(3/2). We observed that the perturbed character is the combined result of the viscosity and the heterogeneity of the blood. A progressive wave type of solution is presented for the evolution equation and the result is discussed. The numerical results indicate that for a certain value of the density parameter sigma, the wave equation loses its dispersive character and the evolution equation degenerates. It is further shown that, for the perturbed KdV equation both the amplitude and the wave speed decay in the time parameter tau.