Search Results

Now showing 1 - 10 of 1320
  • Article
    Citation - WoS: 5
    Citation - Scopus: 6
    Mild Solutions for Conformable Fractional Order Functional Evolution Equations Via Meir-Keeler Type Fixed Point Theorem
    (Univ Nis, Fac Sci Math, 2025) Berrighi, Fatma; Medjadj, Imene; Karapinar, Erdal
    In this study, we delve into the realm of mild solutions for conformable fractional order functional evolution equations, focusing on cases where the fractional order is strictly greater than 1 and less than 2 within a separable Banach space. We demonstrate the existence, uniqueness, attractivity, and controllability of these solutions under local conditions. Our approach involves leveraging a contribution of Meir-Keeler's fixed point theorem alongside the principle of measures of noncompactness. To demonstrate the practical ramifications of our theoretical finds, we provide a specific example that underscores the relevance and applications of the established results.
  • Article
    Citation - WoS: 18
    Citation - Scopus: 21
    Research Trends in Management Issues of Global Software Development: Evaluating the Past To Envision the Future
    (Taylor & Francis inc, 2011) Mishra, Deepti; Mishra, Alok
    This paper presents research trends in management issues (project management, process management, knowledge management, requirements management, configuration management, risk management, quality management) of distributed/global information system development. The main objective is to highlight the current research and practice direction in these areas. The results are based on peer-reviewed conference papers/journal articles, published between 2000 and early 2011. The analysis revealed that most research has been done in project management, process management, knowledge management and requirements management areas while configuration, risk, and quality management issues could get only limited attention in global/distributed information system development. This indicates the need for future research (quantitative and qualitative) in these areas.
  • Article
    Citation - WoS: 5
    Citation - Scopus: 5
    Physical Characterization of Thermally Evaporated Sn-Sb Thin Films for Solar Cell Applications
    (Springer Heidelberg, 2023) Bektas, Tunc; Surucu, Ozge; Terlemezoglu, Makbule; Parlak, Mehmet
    The substitution of Sb in binary SnSe structure may lead to tailoring the physical properties of both SnSe and SbSe, promising absorber layers for thin film solar cells. The resulting Sn-Sb-Se structure could be an outstanding material for photovoltaic applications. In this study, Sn-Sb-Se thin films were deposited by thermal evaporation, and the effect of annealing on the films' structural, optical, and electrical properties were reported. XRD measurement shows that annealing at 300 degrees C yields the best crystalline quality, and structural parameters were calculated using XRD data. SEM and AFM measurements indicate deformation in the film surface after annealing at 400 degrees C. UV-Vis spectroscopy measurement provides a high absorption coefficient which indicates a direct band gap. The band gap and activation energies of the as-grown sample were found as 1.59 eV and 106.1 meV, respectively. The results of SEM, AFM, XRD, Raman, UV-Vis spectroscopy and temperature-dependent photoconductivity measurements were discussed throughout the paper.
  • Article
    Citation - WoS: 15
    Citation - Scopus: 16
    Electrical Parameters of Al/Inse Rf Sensors
    (Iop Publishing Ltd, 2014) Qasrawi, A. F.
    An Al/InSe/C Schottky device is designed on the surface of amorphous InSe thin films. The device is observed to exhibit a switching property at particular biasing voltages. The 'on/off' current ratio is found to be 7.9 and 9.3 at forward and reverse biasing voltages of 2.0 and 2.25 V, respectively. The 'off' and 'on' operational modes are ascribed to the domination of the tunneling of charged particles through a barrier height of 0.83 eV with a depletion region width of 64 nm and due to the domination of the thermionic emission of charged carriers over a barrier height of 0.53 eV, respectively. In addition, the spectral analysis of the capacitance of the device which was carried in the frequency range of 10.0 k-3.0 GHz reflected dc voltage biasing-dependent high quality resonating peaks. The strongest one appeared at a frequency of 36.8 MHz for a biasing voltage of 0.70 V. Furthermore, the loss tangent of the Al/InSe/C device is found to be of the order of 10(-7) at 3.0 GHz. Consistently, the capacitance-voltage spectra of these sensors reflected pronounced tunability up to 100 MHz. The Al/InSe/C device performance, the switching properties and the quality of the resonance peaks indicate the possibility of using these sensors in RF technology.
  • Article
    Citation - WoS: 18
    Citation - Scopus: 21
    Component importance for linear consecutive-k-Out-of-n and m-Consecutive-k-Out-of-n systems with exchangeable components
    (Wiley-blackwell, 2013) Eryilmaz, Serkan
    Measuring the relative importance of components in a mechanical system is useful for various purposes. In this article, we study Birnbaum and Barlow-Proschan importance measures for two frequently studied system designs: linear consecutive k -out-of- n and m -consecutive- k -out-of- n systems. We obtain explicit expressions for the component importance measures for systems consisting of exchangeable components. We illustrate the results for a system whose components have a Lomax type lifetime distribution. (c) 2013 Wiley Periodicals, Inc. Naval Research Logistics, 2013
  • Article
    Citation - WoS: 3
    Citation - Scopus: 3
    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: 1
    Citation - Scopus: 1
    Elimination of Limit Cycles in a Class of Digital Filters Using Single Saturation Nonlinearity
    (Taylor & Francis Ltd, 2008) Singh, Vimal
    Using Lyapunov's direct method, a novel frequency-domain criterion for the elimination of limit cycles in a class of digital filters using single saturation nonlinearity is derived. The criterion turns out to be a generalization and improvement over an earlier criterion due to Kar and Singh. An example showing the effectiveness of the criterion is given. A graphical interpretation of a simplified version (involving one free parameter) of the criterion is discussed.
  • Article
    Citation - WoS: 65
    Citation - Scopus: 72
    The Intuitionistic Fuzzy Electre Model
    (Taylor & Francis Ltd, 2018) Rouyendegh (Babek Erdebilli), Babak Daneshvar; Rouyendegh , Babak Daneshvar
    The purpose of this research is to postulate and define a new model for Multi-Criteria DecisionMaking (MCDM) problems utilizing the Intuitionistic Fuzzy ELimination Et Choix Traduisant la REalite (IFELECTRE) method, otherwise identified as the Intuitionistic Fuzzy Index of Hesitation Degree method. The Intuitionistic Fuzzy Sets (IFS) method offers certain advantages in using vagueness over a Fuzzy Set (FS): the IFELECTRE method is used to handle more complicated problems, whereas the Decision-Makers (DMs) have some vagueness in assigning option values to the objects considered. The processes of evaluating qualitative and quantitative scales are combined in this work and the proposed model enables different DMs to assess and use IFS. The original ELECTRE method cannot be operated effectively owing to a lack of precise information under different conditions.
  • Article
    Citation - Scopus: 1
    Determining the Hydrogen Production Potential of Conmo6se8 Chevrel Phases
    (Institute of Physics, 2025) Gencer, A.; Surucu, O.; Sahin, M.; Ozel, F.; Surucu, G.
    In this study, the ConMo6Se8 (n = 1, 2, 3, and 4) Chevrel phases are investigated by using Density Functional Theory (DFT) to reveal their potential for photocatalytic hydrogen production. The stability conditions of these phases reveal that CoMo6Se8, Co2Mo6Se8, and Co3Mo6Se8 satisfy the thermodynamic and mechanic stability properties, while Co4Mo6Se8 does not satisfy any of these properties. Furthermore, the formation enthalpy of these phases shows that CoMo6Se8, Co2Mo6Se8, and Co3Mo6Se8 can be synthesized experimentally due to having negative formation enthalpy values. Furthermore, the thermal stabilities of the machine-learning (ML) force fields are investigated by ab-initio molecular dynamics (AIMD) calculations. The electronic properties of these phases are also investigated in detail, and it is found that Co3Mo6Se8 has a suitable band gap for photocatalytic water splitting. Concerning the investigation of the valence band and conduction band levels, it is shown that Co3Mo6Se8 has a conduction band minimum level suitable for producing hydrogen. This study is the first attempt to reveal the hydrogen production performance of the ConMo6Se8 (n = 1, 2, 3, and 4) Chevrel phases as far as the literature is concerned, paving the ground for future investigations in this field. © 2024 IOP Publishing Ltd. All rights, including for text and data mining, AI training, and similar technologies, are reserved.
  • Article
    Investigation of Sars-Cov Antibody Levels After Covid-19 Vaccine in Chronic Hepatitis B Patients
    (Aepress Sro, 2024) Kinikli, Sami; Afsar, Fatma Elcin; Dursun, Ali Dogan; Aksoy, Altan; Karahan, Gizem; Cesur, Salih; Urtimur, Ufuk
    AIM: The aim was to compare SARS-CoV-2 IgG antibody levels in chronic hepatitis B patients and healthcare personnel selected as the control group and to determine factors such as age, gender, vaccine type, and number of vaccines that may affect the antibody levels. MATERIALS AND METHODS: 87 chronic hepatitis B (CHB) patients followed in Ankara Training and Research Hospital Infectious Diseases Clinic and Mamak State Hospital Infectious Diseases outpatient clinic and 89 healthcare personnel selected as the control group were included in the study. SARS-CoV-2 IgG antibody levels in the serum samples of patients and healthcare personnel who received the COVID-19 vaccine were studied with the ELISA method in the Microbiology Laboratory of Ankara Training and Research Hospital, using a commercial ELISA kit (Abbott, USA) in line with the recommendations of the manufacturer. In the study, SARS-CoV-2 IgG levels were compared in CHB patients and healthcare personnel. In addition, the relationship between SARS-CoV-2 antibody level, gender, average age, natural history of the disease, number of vaccinations, vaccine type (Coronavac TM vaccine alone, BNT162b2 vaccine alone or Coronavac TM and BNT162b2 vaccine (heterologous vaccination)), treatment duration of CHB was investigated. Statistical analyses were made in the SPSS program. A value of p <= 0.05 was considered statistically significant. FINDINGS: A total of 167 people, including 87 CKD patients and 80 healthcare personnel as the control group, were included in the study. SARS-CoV-2 IgG antibody levels were detected above the cut-off level in the entire study group, regardless of the vaccine type. No difference was detected in SARS-CoV-2 IgG titers after COVID-19 vaccination between CHB patients and healthcare personnel. There was a statistically significant difference in SARS-CoV-2 IgG antibody levels among individuals participating in the study according to vaccine types. Compared to those who received Coronavac TM vaccine alone, the average SARS-CoV-2 IgG level was found to be statistically significantly higher in those who received BNT162b2 vaccine alone or heterologous vaccination with Coronavac TM + BNT162b2 vaccine. There was no difference between the groups in terms of age, gender, number of vaccinations, natural transmission of the disease, and duration of antiviral therapy in the CHD patient group. CONCLUSION: As a result, SARS-CoV-2 IgG antibody levels above the cut-off value were achieved with Coronavac TM and BNT162b2 vaccines in both CHD patients and healthy control groups. however, both CHD patients and healthcare personnel had higher antibody levels than those who received BNT162b2 alone or those who received heterologous vaccination had higher antibody levels than those with Coronavac TM alone. Therefore, if there are no contraindications, BNT162b2 vaccine may be preferred in CHB and health personnel (Tab. 2, Ref. 14) .