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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 Progressive damage analyses of masonry buildings by dynamic analyses(Springer International Publishing AG, 2020-08) Aras, Fuat; Akbaş, Tolga; Ekşi, Hızır; Çeribaşı, SeyitThis study investigates the effects of prescribed damage on the walls of masonry buildings by experimental and numerical methods. Ambient vibration survey method was applied to an existing, two-story, unreinforced masonry building to determine its dynamic characteristics, such as mode shapes and natural frequencies. Then, the walls on two exterior sides of the building were demolished, and dynamic testing was repeated for the damaged building. As the next step, the amount of damage on the building was increased by more impacts, and the dynamic characteristics of the heavily damaged building were identified. The results obtained from the undamaged, damaged and heavily damaged building were compared, and the damage effect on the natural frequencies of the building was noted. Besides, finite element analyses of the undamaged, damaged and heavily damaged buildings were performed. It was found that, the numerical models, constructed with code-based material properties, do not sufficiently represent the dynamic behavior of masonry buildings. Secondly, as the result of the sustained damage, while the experimental and the numerical modal analyses revealed the decrease in the dominant frequencies of the building, the difference between them increases with the severity of the damage. With the framework presented in this study, the behavior of masonry buildings can better be determined and used for analysis purposes.Yayın Projected changes in extreme temperature and precipitation indices over CORDEX-MENA domain(MDPI AG, 2021-05) Öztürk, Tuğba; Saygılı Aracı, Fatma Sibel; Kurnaz, Mehmet LeventIn this study, projected changes in climate extreme indices defined by the Expert Team on Climate Change Detection and Indices were investigated over Middle East and North Africa. Changes in the daily maximum and minimum temperature-and precipitation-based extreme indices were analyzed for the end of the 21st century compared to the reference period 1971–2000 using regional climate model simulations. Regional climate model, RegCM4.4 was used to downscale two different global climate model outputs to 50 km resolution under RCP4.5 and RCP8.5 scenarios. Results generally indicate an intensification of temperature-and precipitation-based extreme indices with increasing radiative forcing. In particular, an increase in annual minimum of daily minimum temperatures is more pronounced over the northern part of Mediterranean Basin and tropics. High increase in warm nights and warm spell duration all over the region with a pronounced increase in tropics are projected for the period of 2071–2100 together with decrease or no change in cold extremes. According to the results, a decrease in total wet-day precipitation and increase in dry spells are expected for the end of the century.Yayın Adaptive Volterra channel equalisation with lattice orthogonalisation(Institution of Engineering and Technology, 1998-04) Özden, Mehmet Tahir; Kayran, Ahmet Hamdi; Panayırcı, ErdalThe authors present a new recursive least-squares adaptive nonlinear equaliser based on Volterra series expansion. The main approach is to transform the nonlinear equalisation problem into an equivalent multichannel, but linear, equalisation problem. Then the multichannel input signal is completely orthogonalised using sequential processing multichannel lattice stages. With the complete orthogonalisation of the input signal, only scalar operations are required, instability problems owing to matrix inversion are avoided, and good numerical properties are achieved. Avoidance of matrix inversion and vector operations reduce the complexity considerably, and make the filter highly modular and suitable for VLSI implementation. Several experiments demonstrating the performance under different channel distortion and channel noise conditions are also included in the paper.Yayın Analysis of self-noise in a clock recovery system with a high-order nonlinearity(IEEE-INST Electrical Electronics Engineers Inc, 2003-11) Panayırcı, ErdalThis correspondence presents a new technique to compute efficiently the spectra of the in-phase (I) and quadrature (Q) components as well as the cross-spectrum of the in-phase and quadrature (I-Q) components of self-noise appearing at the output of the zero-memory, high-order nonlinear (NL) device employed in a clock recovery system. It is known that these spectra play an important role in the phase jitter performance of the clock regenerator. The results are very general and applicable to many cases of practical interest. Numerical examples and computer simulations provided show that the new approach yields very accurate results and is much faster than the usual computer simulation method. in addition, we give a theorem to show that for the signal shapes having linear phase, the cross-power spectrum of self-noise is zero. We also provide a general expression for the jitter variance of the generated clock signal in terms of the power spectra of self-noise in-phase and quadrature components. It is shown that the cross-power spectrum will also contribute to timing jitter if the selected signaling shape does not have any symmetry in time domain. The optimal periodic sampling instants Eire determined by the axis crossings of the clock signal in the positive direction. The axis is set at a level whereby the jitter variance takes on a minimum value. It is concluded that when the cross-power spectrum is zero for all frequencies then the optimal sampling instants occur at the positive zero crossings of the clock signal and only the Q noise contributes to the timing jitter performance.Yayın Least minimum symbol error rate based post-distortion for adaptive mobile VLC transmission with receiver selection(Elsevier B.V., 2021-08) Miramirkhani, Farshad; Karbalayghareh, Mehdi; Mitra, RangeetIn the context of beyond-5G indoor communication systems, visible light communication (VLC) has emerged as a viable supplement for existing RF-based systems and as an enabler for high datarate communications. However, the existing indoor VLC systems are limited by detrimental outages caused by fluctuations in the VLC channel-gain due to user-mobility. Furthermore, the nonlinear characteristics of the light-emitting diode (LED) degrade the performance of VLC systems in the highpower regime by warping the input constellation. Additional performance-limits are introduced by inter-symbol interference (ISI) due to finite modulation-bandwidth of LEDs, and reflections from walls. In this paper, a random Fourier feature (RFF) based post-distorter is considered for mitigating the LED nonlinearity, and relevant expressions for the signal to noise ratio (SNR) are derived for a direct current biased optical orthogonal frequency division multiplexing (DCO-OFDM) system. Based on the derived expressions for SNR, the effects of user-mobility and ISI are mitigated by a DCO-OFDM based adaptive VLC transmission technique, which varies the transmission-rate/modulation-order under a specified error-rate constraint. Simulations are presented over channels obtained by ray-tracing, which indicates that the proposed algorithm achieves superior data-rates with a significantly lower error-rate.Yayın Affective theory of mind in human aging: is there any relation with executive functioning?(Routledge, 2019-04) Yıldırım, Elif; Soncu Büyükişcan, Ezgi; Gürvit, İbrahim HakanTheory of Mind (ToM) refers to the ability to make inferences on other’s mental or emotional states. Although there is evidence suggesting that impaired executive functions due to aging could have a negative impact on cognitive ToM, there is still controversy about the effect of age and age-related executive dysfunctions on affective ToM. To investigate affective ToM in healthy aging and its relationship with executive functions, we examined Reading Mind in the Eyes Test (RMET) performance and executive functions among young and older adults. There was no significant difference between age groups regarding their RMET scores. While affective ToM was correlated to executive functioning within the younger group, short term memory was found to be associated with RMET performance among older participants. Furthermore, within the older group, women performed better than men. Our findings suggest a preserved ability of affective ToM in healthy aging, which appears to be independent of executive functioning.Yayın Cognitive reserve and aging: impacts on theory of mind and executive functions(Routledge, 2025-03) Şandor, Serra; Hıdıroğlu Ongun, Ceren; Yıldırım, ElifAim: This study examines the effects of cognitive reserve (CR) on Executive Functions (EF) and Theory of Mind (ToM). While CR is suggested to mitigate age-related cognitive decline, its relationship with social cognition remains limited and inconsistent in the literature. It was hypothesized that the effect of CR on ToM might be indirect, mediated by EF and working memory. Methods: 225 cognitively healthy participants were included. CR was measured with the Cognitive Reserve Index Questionnaire, EF with verbal fluency and the Stroop Test, and WM using digit span tasks. Structural Equation Modeling was used to analyze the relationships among CR, EF, WM, and SC, controlling for age and gender. Results: CR was significantly associated with both RMET and FPRT performances. Mediation analysis revealed the direct effects of CR on RMET performance, while the effects on FPRT performance were mediated by executive functions. WM had a partial mediating effect on EF and ToM, but did not directly influence FPRT. Education was most strongly associated with RMET performance, while leisure activities were linked to FPRT performance. Conclusion: These findings suggest that CR indirectly supports ToM by enhancing EF and highlight the importance of interventions aimed at strengthening executive control to support social cognition in aging.Yayın Design of voltage-mode and current-mode PID controllers using a single Add-Differentiate IC (AD-IC)(Birkhauser, 2025-12-22) Minayi, Elham; Göknar, İzzet CemIn this paper, voltage and current mode proportional–integral–derivative (PID) controller circuits are presented in one topology, utilizing only a single active component, Add-Differentiate Integrated Circuit (AD-IC) along with two passive resistors and two passive capacitors. The effectiveness and performance of the proposed circuits are validated through sensitivity, non-ideality analyses and PSPICE and MatLab simulations.
