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  • Article
    Citation - WoS: 20
    Citation - Scopus: 20
    Properties of the Pc(4312) pentaquark and its bottom partner
    (Iop Publishing Ltd, 2021) Azizi, K.; Sarac, Y.; Sundu, H.
    We present an analysis of the newly observed pentaquark P-c(4312)(+) to shed light on its quantum numbers. To do that, the QCD sum rules approach is used. The measured mass of this particle is close to the Sigma D-++(c)- threshold and has a small width, which supports the possibility of its being a molecular state. We consider an interpolating current in a molecular form and analyze both the positive and negative parity states with spin-. We also consider the bottom counterpart of the state with similar molecular form. Our mass result for the charm pentaquark state supports that the quantum numbers of the observed state are consistent with J(P) = 1/2(-).
  • Article
    Citation - WoS: 32
    Citation - Scopus: 32
    Capacitance, Conductance, and Dielectric Characteristics of Al/Tio2< Diode
    (Springer, 2021) Gullu, H. H.; Yildiz, D. E.
    In this study, electrical properties of the Al/TiO2/p-Si diode structure with an atomic layer deposited TiO2 interface layer are investigated by current-voltage (I-V), capacitance-voltage (C - V), and conductance-voltage (G - V) measurements. It shows a rectifying behavior with about four order of rectification factor, and barrier height and ideality factor are calculated from the rectification curve. Dielectric parameters are determined from frequency-dependent C - V and G - V relations. The experimental results show that both of these curves are in a strong response to the frequency and bias voltage. They are found in decreasing behavior with increasing frequency, and both of them increase with increase in bias voltage although there are different increasing trends. At reversed bias voltage region, barrier potential, Fermi level energy, and interface charge carrier contribution are evaluated by using 1/C-2 - V plot. Series resistance values are also calculated under the variation of frequency and voltage. Thus, the capacitive characteristics of the diode are corrected by eliminating series resistance contribution together with the possible effect on interface charge carriers. Detailed information is obtained by determining electronic parameters affected by interface states over a wide frequency range (1 kHz to 1 MHz). At this point, strong response to the frequency is observed for the dielectric constant. Under the effect of interfacial polarization at low-frequency region, interface charge contribution to the capacitive response of the diode is obtained. Further analysis is performed on electrical modulus and impedance values derived from experimental dielectric data. Existence of interfacial layer capacitance is detailed by extracting distribution of interface charges from capacitance and conductance profiles of the diode under the effect of frequency.
  • Article
    Citation - WoS: 6
    Citation - Scopus: 4
    Latent Dynamics of Movement Formation: the Kurdish Case in Turkey (1940s-1960s)
    (Sage Publications Ltd, 2015) Ozen, Hayriye
    The attention of social movement studies has so far tended to focus on visible phases of movements, neglecting latent ones. This study argues that invisible mobilizations may be critical in preparing the groundwork of public mobilizations, particularly in authoritarian contexts. Using a process-oriented constructivist account of mobilization which incorporates insights from resistance studies, this article analyzes the Kurdish case in Turkey in the authoritarian 1940s and semi-authoritarian 1950s. Based on in-depth interviews, memoirs, newspaper reports, and official documents, it is demonstrated that a latent Kurdish dissent emerged in this period through the constitution of a sense of shared grievance and common identity both in hidden ways within the submerged networks of Kurdish students and professionals, and in public and visible, yet disguised, ways. Incubating the movement out of the gaze of the authorities within the authoritarian context, this latent dissent formed the groundwork of public acts of defiance and mobilization which emerged towards the end of the 1950s as the political changes encouraged Kurdish dissenters to publicly declare their opposition, and expanded in the more liberal context of the 1960s. Resume Les etudes des mouvements sociaux ont eu tendance jusqu'a present a privilegier les phases visibles de ces mouvements, negligeant les stades latents. Cette etude soutient que les mobilisations invisibles peuvent etre essentielles pour preparer le terrain des mobilisations publiques, en particulier dans un contexte autoritaire. En s'appuyant sur une interpretation constructiviste, axee sur le processus de mobilisation et reunissant des idees tirees des etudes des mouvements de resistance, cet article analyse le cas kurde dans la Turquie autoritaire des annees quarante et semi-autoritaire des annees cinquante. Fonde sur des entretiens approfondis, des biographies, des articles de journaux et des documents officiels, ce travail met en evidence l'apparition au cours de cette periode d'une dissidence kurde latente grace a la constitution d'un sentiment partage de mecontentement et d'identite commune au sein des reseaux secrets des etudiants et professionnels kurdes, de facon a la fois invisible et publique, mais dissimulee. Couvant a l'abri des regards des gouvernements autoritaires, cette dissidence latente a pose les bases des manifestations publiques de defiance et de mobilisation qui sont apparues a la fin des annees cinquante a l'occasion des changements politiques ayant encourage les dissidents kurdes a declarer publiquement leur opposition et favorise les mouvements sociaux dans le contexte plus liberal des annees soixante. Resumen La atencion de los estudios sobre movimientos sociales hasta ahora ha tendido a centrarse en las fases visibles de los movimientos, dejando de lado los latentes. Este estudio sostiene que las movilizaciones invisibles pueden ser centrales para la preparacion de las bases de movilizaciones publicas, en particular en contextos autoritarios. A partir de un relato constructivista orientado a los procesos de movilizacion que incorpora perspectivas de estudios de resistencia, este trabajo analiza el caso kurdo en Turquia en la decada autoritaria de 1940 y semi-autoritaria de 1950. Sobre la base de entrevistas en profundidad, memorias, informes de prensa y documentos oficiales, se demuestra que una disidencia kurda latente surgio en este periodo a traves de la constitucion de un sentimiento de agravio compartida y de identidad comun tanto en formas ocultas dentro de las redes sumergidas de estudiantes y profesionales kurdos, asi como de maneras publicos y visibles, aunque disfrazadas. Incubando el movimiento fuera de la mirada de las autoridades en el contexto autoritario, esta disidencia latente formo las bases del acto publico de rebeldia y movilizacion que surgio a finales de la decada de 1950 como los cambios politicos alentados disidentes kurdos para declarar publicamente su oposicion, y ampliado en el contexto mas liberal de la decada de 1960.
  • Article
    Citation - WoS: 7
    Citation - Scopus: 7
    Finite Element Analysis of Frames With Reinforced Concrete Encased Steel Composite Columns
    (Mdpi, 2022) Tunc, Gokhan; Othman, Mohammed Moatasem; Mertol, Halit Cenan
    Structural frame systems that consists of concrete-encased-steel-embedded composite columns and reinforced concrete beams are typically used in mid-rise to tall buildings. In order to understand their overall structural behavior, a total of 12 frame models with high and low ductility features were constructed and analyzed using LS-DYNA software. Two of these models were validated using the results of previously tested frames. The remaining 10 models were studied to predict the behavior of frames with varying concrete strengths, reinforcement configurations, and structural steel sections under vertical and lateral loads. The results were investigated in terms of cracks and failure patterns, load-deflection relationships, energy dissipation, and stiffness degradation. The analytical results indicated that the high ductile frame models showed slightly better lateral load carrying performances compared to low ductility frame models. Moreover, the analytical studies demonstrated that the existence of structural steel in a column, regardless of its cross-sectional shape, was the most important parameter in improving the lateral load carrying capacity of a frame.
  • Article
    Citation - WoS: 22
    Citation - Scopus: 36
    An Analysis of Course Characteristics, Learner Characteristics, and Certification Rates in MITx MOOCs
    (Athabasca Univ Press, 2020) Cagiltay, Nergiz Ercil; Cagiltay, Kursat; Celik, Berkan; Software Engineering
    Massive Open Online Courses (MOOCs), capable of providing free (or low cost) courses for millions of learners anytime and anywhere, have gained the attention of researchers, educational institutions, and learners worldwide. Even though they provide several benefits, there are still some criticisms of MOOCs. For instance, MOOCs' high dropout rates or predominantly elite participation are considered to be important problems. In order to develop solutions for these problems, a deeper understanding of MOOCs is required. Today, despite the availability of several research studies about MOOCs, there is a shortage of in-depth research on course characteristics, learner characteristics, and predictors of certification rates. This study examined MOOC and learner characteristics in detail and explored the predictors of course certification rates based on data from 122 Massachusetts Institute of Technology MOOCs (MITx) on edX platform as well as data about the 2.8 million participants registered in these MOOCs. The results indicated that as the number of courses offered and the number of learners enrolled increased in years, there was a decrease in the certification rates among enrolled learners. According to our results, the number of average chapters completed, total forum messages, and mean age predicted course certification rates positively. On the other hand, the total number of chapters in a course predicted the course certification rates negatively. Based on these results, shorter and more interactive MOOCs are recommended by considering the needs of the learners, course content design, and strategies encouraging the enrolled students to enter the courses.
  • Article
    Citation - WoS: 4
    Citation - Scopus: 5
    Experimental Investigation of Communication Performance of Drones Used for Autonomous Car Track Tests
    (Mdpi, 2021) Yildiz, Melih; Bilgic, Burcu; Kale, Utku; Rohacs, Daniel
    Autonomous Vehicles (AVs) represent an emerging and disruptive technology that provides a great opportunity for future transport not only to have a positive social and environmental impact but also traffic safety. AV use in daily life has been extensively studied in the literature in various dimensions, however; it is time for AVs to go further which is another technological aspect of communication. Vehicle-to-Vehicle (V2V) technology is an emerging issue that is expected to be a mutual part of AVs and transportation safety in the near future. V2V is widely discussed by its deployment possibilities not only by means of communication, even to be used as an energy transfer medium. ZalaZONE Proving Ground is a 265-hectare high-tech test track for conventional, electric as well as connected, assisted, and automated vehicles. This paper investigates the use of drones for tracking the cars on the test track. The drones are planned to work as an uplink for the data collected by the onboard sensors of the car. The car is expected to communicate with the drone which is flying in coordination. For the communication 868 MHz is selected to be used between the car and the drone. The test is performed to simulate different flight altitudes of drones. The signal strength of the communication is analyzed, and a model is developed which can be used for the future planning of the test track applications.
  • Article
    Citation - WoS: 11
    Citation - Scopus: 13
    The Convergence of q-bernstein Polynomials (0 < q < 1) in the Complex Plane
    (Wiley-v C H verlag Gmbh, 2009) Ostrovska, Sofiya
    The paper focuses at the estimates for the rate of convergence of the q-Bernstein polynomials (0 < q < 1) in the complex plane. In particular, a generalization of previously known results on the possibility of analytic continuation of the limit function and an elaboration of the theorem by Wang and Meng is presented. (C) 2009 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim
  • Article
    Citation - WoS: 13
    Citation - Scopus: 12
    Asymmetry in Farm-Retail Price Transmission in the Turkish Fluid Milk Market
    (Bononia Univ Press, 2014) Bor, Ozgur; Smihan, Mustafa; Bayaner, Ahmet; Economics
    This study investigates the price asymmetry in farm-retail price transmission in the Turkish fluid milk market. An asymmetric error correction model is applied on the monthly price data, and the results suggest that there is a positive price asymmetry in the farm-retail price transmission in the Turkish milk market. That is, the retail prices tend to adjust more quickly to the input price increases than to their decreases which yield welfare losses to the consumers. In addition, cointegration results imply that there is a significant market power in the Turkish fluid milk market. Therefore, the results of this paper support the view that retailers (as well as processors) can exercise significant market power as highlighted by asymmetric price responses in the Turkish milk market.
  • Article
    Polysulfur Copolymer as a Support Material for the Preparation of a Novel Multifunctional Photocatalytic Composite Material
    (Springer, 2025) Kesimal, Busra; Guner, Zuhal Vanli; Cihaner, Atilla; Kaya, Murat
    One-step addition of magnetic nanoparticles and titanium dioxide nanoparticles into polysulfur copolymer as cheap and available support was reported for the first time to prepare the magnetically separable heterogeneous catalyst, PolyS-MNP-TiO2. The photocatalytic activities of the PolyS-MNP-TiO2 composite material and its constituents were examined in the methylene blue (MB) degradation, textile-based wastewater simulant, exposed to solar light. Detailed characterization of the catalysts was performed with SEM, TEM, and EDX measurements. The photocatalytic activity of the resulting composite was figured out in the removal of methylene blue dye by using a solar simulator. Significantly, the as-prepared PolyS-MNP-TiO2 exhibits exceptional photocatalytic activity and total degradation of dye molecules was achieved in 60 min. Additionally, the prepared novel photocatalyst showed enhanced stability and reusability due to the magnetic behavior of the composite material and the same portion of catalyst was used in five successive tries without apparent loss in catalytic activity by eliminating long and work-loaded processes like filtration and centrifugation.
  • Article
    Citation - WoS: 7
    Citation - Scopus: 7
    Plasmon-Electron Dynamics at the Au/Inse and Y/Inse Interfaces Designed as Dual Gigahertz-Terahertz Filters
    (Elsevier Gmbh, Urban & Fischer verlag, 2017) Alharbi, S. R.; Qasrawi, A. F.
    In this work, the X-ray diffraction, the Scanning electron microscopy, the energy dispersive X-ray, the Raman, The UV-vis light and the impedance spectral techniques are employed to explore the structural, vibrational, optical and electrical properties of the Au/InSe and Y/InSe thin film interfaces. It was shown that with its amorphous nature of crystallization, the InSe thin films exhibited n-type conductivity due to the 3% excess selenium. For this form of InSe, the only active Raman spectral line is 121 (cm(-1)). In addition to the design of the energy band diagram, the analysis the dielectric spectra and the optical conductivities were possible in the frequency range of 270-1000 THz. The modeling of the optical conductivities of the Au, Y, Au/InSe and Y/InSe with the help of Lorentz approach for optical conduction, assured that the conduction is dominated by the resonant plasmon-electron interactions at the metals and metals/semiconductors interfaces. It also allowed tabulating the necessary parameters for possible applications in terahertz technology: These parameters are the electron effective masses, the free electron densities, the electron bounded plasmon frequencies, the electron scattering times, the reduced resonant frequencies and the drift mobilities. On the other hand, the impedance spectral analysis of the Y/InSe/Au interfaces in the frequency range of 0.01-1.80 GHz, revealed negative capacitance effect associated with band filter features that exhibit maximum transition line at 1.17 GHz. This value nominates the interface as a member of filter classes in the gigahertz technology. (C) 2017 Elsevier GmbH. All rights reserved.