Search Results

Now showing 1 - 10 of 57
  • Article
    Citation - WoS: 7
    Citation - Scopus: 7
    Repetition or Alternation of Context Influences Sequential Congruency Effect Depending on the Presence of Contingency
    (Springer Heidelberg, 2017) Atalay, Nart Bedin; Inan, Asli Bahar
    The sequential congruency effect (SCE) is defined as the decrease in the congruency effect following incongruent trials compared to congruent trials. The effect of context repetition on the SCE was investigated in four experiments. In all the experiments, dynamic visual white noise was used as the contextual feature, and the number of congruent and incongruent trials was equal. In Experiments 1 and 2, by using eight-value Flanker and Stroop tasks, and excluding stimulus- and response-feature repetitions from the analysis, a SCE was observed in both context repetition and alternation conditions. In Experiment 3, using a two-value Flanker task, all trials consisted of stimulus- and response-feature repetitions, and a SCE was only observed in the context repetition condition. In Experiment 4, we used a four-value Flanker task, which enabled half of the trials to be partial/complete repetitions and the other half to be complete alternations. A SCE was observed in both context repetition and alternation conditions irrespective of the stimulus- and response-feature repetitions. This pattern of results suggested that the effects of context repetition on the SCE are subject to a number of factors including stimulus- and response-feature repetitions and contingency biases. When contingency information exists, the presence of stimulus- and response-feature repetitions was no longer effective in yielding effects of context repetition on the SCE. These findings suggest that the usage of information registered in episodic event representations including stimulus-, response- and contextual-features, control parameters and contingency biases results from interactions of a complex pattern of mechanisms, yet to be further explored.
  • Article
    Citation - WoS: 162
    Citation - Scopus: 167
    Economic Policy Uncertainty, Energy Consumption and Carbon Emissions in G7 Countries: Evidence From a Panel Granger Causality Analysis
    (Springer Heidelberg, 2020) Pirgaip, Burak; Dincergok, Burcu
    We investigate the causal relationship between economic policy uncertainty (EPU) and energy consumption and carbon (CO2) emissions in G7 countries. We employ a bootstrap panel Granger causality test developed by Konya (Econ Model 23:978-992, 2006), using a yearly data set spanning from 1998 to 2018. Our test results provide significant support for a unidirectional causality running from EPU to energy consumption in Japan; from EPU to CO2 emissions in the USA and Germany; and from EPU to both energy consumption and CO2 emissions in Canada. In Italy, causality runs from CO2 emissions to EPU, but a bidirectional causality between EPU and energy consumption exists as well. We also explore a unidirectional causality that runs from energy consumption to CO2 in the USA. Based on the overall findings, we draw important implications for policymakers and we strongly recommend for G7 countries to take into account possible negative effects of EPU on energy conservation policies, which should be embarked upon to reduce energy consumption and CO2 emissions, as committed in their recent climate mandate.
  • Article
    A New Conservative Numerical Method for Strongly Coupled Nonlinear Schrödinger Equations
    (Springer Heidelberg, 2025) Ors, Ridvan Fatih; Koroglu, Canan; Aydin, Ayhan
    In this paper, a numerical method based on the conservative finite difference scheme is constructed to numerically solve the strongly coupled nonlinear Schr & ouml;dinger (SCNLS) equation. Conservative properties such as energy and mass of the SCNLS equation have been proven. In particular a fourth-order central difference scheme is used to discretize the the spatial derivative and a second-order Crank-Nicolson type discretization is used to discretize the temporal derivative. It has been shown that the proposed scheme preserves the discrete mass and energy. The existence of discrete solution is also investigated. Several numerical results are given to demonstrate the preservation properties of the new method. Also, the effect of the linear coupling parameters on the evolution of solitary waves is investigated.
  • Article
    Citation - WoS: 2
    Citation - Scopus: 2
    Optical Characterization of Nabi(moo4)2< Crystal by Spectroscopic Ellipsometry
    (Springer Heidelberg, 2024) Guler, I.; Isik, M.; Gasanly, N. M.
    The compound NaBi(MoO4)(2) has garnered significant interest in optoelectronic fields. This study employs spectroscopic ellipsometry to thoroughly examine the linear and nonlinear optical characteristics of NaBi(MoO4)(2) crystals, offering detailed insights into their optical behavior. Our investigation presents a precise method for discerning the crystal's spectral features, revealing the spectral variations of key optical parameters such as refractive index, extinction coefficient, dielectric function, and absorption coefficient within the 1.2-5.0 eV range. Through analysis, we determined optical attributes including bandgap energy, critical point energy, and single oscillator parameters. Additionally, we explored the nonlinear optical properties of NaBi(MoO4)(2), unveiling potential applications such as optoelectronic devices, frequency conversion, and optical sensors. This study enhances comprehension of optical properties of NaBi(MoO4)(2), underscoring its significance in future optical and electronic advancements.
  • Article
    Citation - WoS: 14
    Citation - Scopus: 15
    Yielding of Two-Layer Shrink-Fitted Composite Tubes Subject To Radial Pressure
    (Springer Heidelberg, 2005) Eraslan, AN; Akis, T
    Yielding of two-layer shrink-fitted composite tubes with axially constrained ends subject to either internal or external pressure is investigated in detail. In the framework of small deformations, a state of plane strain and von Mises yield criterion, analytical expressions are obtained for critical values of the pressure leading to plastic flow. It is shown that, depending on material properties and tube dimensions, different modes of plastic deformation may occur. Yielding may commence at the inner tube or at the outer tube or simultaneously in both tubes. The conditions for different nature of plastic flow are determined. Using analytical expressions obtained for critical values of the parameters and properties of real engineering materials, various numerical examples are handled and the variation of elastic limit pressure with interference and interface radius is explained.
  • Article
    Citation - WoS: 29
    Citation - Scopus: 36
    Fixed Point Results on a Class of Generalized Metric Spaces
    (Springer Heidelberg, 2012) Aydi, Hassen; Karapinar, Erdal; Lakzian, Hossein
    Brianciari ('A fixed point theorem of Banach-Caccioppoli type on a class of generalized metric spaces,' Publ. Math. Debrecen 57 (2000) 31-37) initiated the notion of the generalized metric space as a generalization of a metric space in such a way that the triangle inequality is replaced by the 'quadrilateral inequality,' d(x, y) <= d(x, a) + d(a, b) + d(b, y) for all pairwise distinct points x, y, a, and b of X. In this paper, we establish a fixed point result for weak contractive mappings T : X -> X in complete Hausdorff generalized metric spaces. The obtained result is an extension and a generalization of many existing results in the literature.
  • Article
    Factors Influencing the Transition Time From Psoriasis to Psoriatic Arthritis: A Real-World Multicenter Analysis
    (Springer Heidelberg, 2025) Kilic, Gamze; Kilic, Erkan; Tekeoglu, Ibrahim; Sargin, Betul; Cengiz, Gizem; Balta, Nihan Cuzdan; Nas, Kemal
    To identify clinical and demographic predictors associated with the timing of transition from psoriasis (PsO) to psoriatic arthritis (PsA), and to compare the characteristics of patients with concurrent PsO-PsA onset versus those with prolonged transition. A multi-center, observational study was conducted using data from the Turkish League Against Rheumatism (TLAR) network including PsA patients fulfilling CASPAR criteria. Patients were categorized into two groups: Group 1 (concurrent PsO and PsA onset within +/- 1 year) and Group 2 (prolonged transition to PsA, > 1 year after PsO). Demographic, clinical, and laboratory characteristics, disease activity, and patient-reported outcomes were compared between groups. Logistic regression was employed to determine independent predictors of prolonged transition. Among 799 patients (mean age 46.8 +/- 12.3 years), 237 (29.7%) had concurrent onset and 562 (70.3%) had a prolonged transition, with a mean PsO-to-PsA interval of 12.9 +/- 9.6 years. Depression (p = 0.005) and fatigue levels (p = 0.011) were significantly higher in patients with prolonged transition to PsA. Multivariate analysis revealed that scalp psoriasis (OR = 7.162), nail psoriasis (OR = 3.270), family history of PsO (OR = 1.813), and enthesitis ever (OR = 2.187) were associated with prolonged transition. Conversely, family history of PsA (OR = 0.421) and older age at PsO onset (OR = 0.957) predicted shorter transition. Prolonged transition from PsO to PsA is influenced by distinct clinical and demographic factors. Scalp/nail psoriasis, family history of PsO, and enthesitis ever may signal higher risk for prolonged PsA onset. Recognizing these markers can support timely referral and intervention, minimizing diagnostic delay and improving long-term patient outcomes.
  • Article
    Citation - WoS: 5
    Citation - Scopus: 7
    Emulating Erasmus? Turkey's Mevlana Exchange Program in Higher Education
    (Springer Heidelberg, 2019) Yilmaz, Gozde
    In today's world, globalization and internationalization of education necessitate new initiatives to catch the new era. Turkey, as a country in between the east and the west, attempts to do so through its recent exchange program in higher education. Interestingly, Turkey's Mevlana exchange program as an ambitious project in higher education denotes an instance of policy transfer: taking the EU model (i.e., Erasmus) and slightly adjusting it to the national circumstances. This article unpacks Turkey's Mevlana program to demonstrate the process of policy transfer by focusing on different questions posed within the policy transfer literature. It argues that Mevlana is drawn from Erasmus, and it is created as a tool of soft power that is increasingly exercised by Turkey due to its changing focus within the Turkish foreign policy of 2000s.
  • Article
    Citation - WoS: 21
    Citation - Scopus: 21
    A Study on the Dark and Illuminated Operation of Al/Si3< Schottky Photodiodes: Optoelectronic Insights
    (Springer Heidelberg, 2024) Surucu, Ozge; Yildiz, Dilber Esra; Yildirim, Murat
    This work extensively investigates the operation of an Al/ Si3N4/p-Si Schottky-type photodiode under dark and varying illumination intensities. The photodiode is fabricated by employing the metal-organic chemical vapor deposition (MOCVD) method. A thorough electrical characterization is performed at room temperature, encompassing measurements of current-voltage (I-V), current-time (I-t), capacitance-time (C-t), and conductance time (G-t). The photodiode's rectification factor and reverse bias area increased under illumination. The relationship between light power density, barrier height, and diode ideality factor is found. The study also found a strong correlation between light intensity and applied voltage on series resistance (R-s) and shunt resistance (R-sh). R-s values are calculated using Cheung's functions, revealing the diode's resistance behavior. The study also examines the photodiode's photoconductivity and photoconductance, finding a non-linear relationship between photocurrent and illumination intensity, suggesting bimolecular recombination. Calculated photosensitivity (K), responsivity (R), and detectivity (D*) values show the device's light response effectiveness, but efficiency decreases at higher illumination intensities. Transient experiments indicate stable and reproducible photocurrent characteristics, revealing photogenerated charge temporal evolution. This study provides a complete understanding of the Al/Si3N4/p-Si Schottky photodiode's behavior under different illumination intensities. The findings advance optoelectronic device knowledge and enable their use in advanced technologies.
  • Article
    Citation - WoS: 6
    Citation - Scopus: 6
    Consistency of Spatiotemporal Variability of Modis and Era5-Land Surface Warming Trends Over Complex Topography
    (Springer Heidelberg, 2023) Yilmaz, Meric
    In this study, the trend of widely used MODIS MxD11 and MxD21 Land Surface Temperature (LST) and ERA5-Land Skin Temperature (SKT) and 2 m air temperature products were validated using 2 m air temperature trends obtained by ground observations from 266 stations in 2000-2021 over Turkey, known to have complex topography. The results show that colder regions have substantially higher temporal temperature variability than warmer ones. MxD21 and MxD11 products are 4.4 & DEG;C and 2.9 & DEG;C warmer than ERA5-Land products, respectively, while ERA5-Land products (SKT and 2 m) have nearly similar averages (12.5 & DEG;C). The consistency between MODIS and ERA5-Land data is significantly lower over areas with more complex topography and irrigation activities, despite the fact that the products show a high linear relationship over the study area. While February trends are consistently much higher than other months (2.2 and 1.4 & DEG;C/decade for MODIS and ERA5-Land, respectively), overall MODIS skin temperature products (0.7 & DEG;C/decade) generally exhibit smaller trends than ERA5-Land skin and air temperature trends (0.94 & DEG;C/decade). The results suggested that MODIS and ERA5-Land trends, which are highly consistent with observations, might replace observations in the absence of long-term station-based records.