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Language: enPublisher: Cambridge Univ Press

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Now showing 1 - 10 of 27
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    Editorial
    Orthogonal Polynomials and Continued Fractions From Euler's Point of View Preface
    (Cambridge Univ Press, 2008) Khrushchev, Sergey
    [No Abstract Available]
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    Book Part
    Continued Fractions: Euler's Influence
    (Cambridge Univ Press, 2008) Khrushchev, Sergey
    [No Abstract Available]
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    Article
    On the Resolvent of the Laplace-Beltrami Operator in Hyperbolic Space
    (Cambridge Univ Press, 2015) Guseinov, Gusein Sh.
    In this paper, a detailed description of the resolvent of the Laplace-Beltrami operator in n-dimensional hyperbolic space is given. The resolvent is an integral operator with the kernel (Green's function) being a solution of a hypergeometric differential equation. Asymptotic analysis of the solution of this equation is carried out.
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    Article
    Citation - WoS: 1
    Citation - Scopus: 2
    Computing Minimal Signature of Coherent Systems Through Matrix-Geometric Distributions
    (Cambridge Univ Press, 2021) Eryilmaz, Serkan; Eryılmaz, Serkan; Tank, Fatih; Eryılmaz, Serkan; Industrial Engineering; Industrial Engineering
    Signatures are useful in analyzing and evaluating coherent systems. However, their computation is a challenging problem, especially for complex coherent structures. In most cases the reliability of a binary coherent system can be linked to a tail probability associated with a properly defined waiting time random variable in a sequence of binary trials. In this paper we present a method for computing the minimal signature of a binary coherent system. Our method is based on matrix-geometric distributions. First, a proper matrix-geometric random variable corresponding to the system structure is found. Second, its probability generating function is obtained. Finally, the companion representation for the distribution of matrix-geometric distribution is used to obtain a matrix-based expression for the minimal signature of the coherent system. The results are also extended to a system with two types of components.
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    Article
    Citation - WoS: 2
    Citation - Scopus: 1
    Prediction of the Onset of Shear Localization Based on Machine Learning
    (Cambridge Univ Press, 2023) Akar, Samet; Ayli, Ece; Ulucak, Oguzhan; Ugurer, Doruk
    Predicting the onset of shear localization is among the most challenging problems in machining. This phenomenon affects the process outputs, such as machining forces, surface quality, and machined part tolerances. To predict this phenomenon, analytical, experimental, and numerical methods (especially finite element analysis) are widely used. However, the limitations of each method hinder their industrial applications, demanding a reliable and time-saving approach to predict shear localization onset. Additionally, since this phenomenon largely depends on the type and parameters of the constitutive material model, any change in these parameters requires a new set of simulations, which puts further restrictions on the application of finite element modeling. This study aims to overcome the computational efficiency of the finite element method to predict the onset of shear localization when machining Ti6Al4V using machine learning methods. The obtained results demonstrate that the FCM (fuzzy c-means) clustering ANFIS (adaptive network-based fuzzy inference system) has given better results in both training and testing when it is compared to the ANN (artificial neural network) architecture with an R-2 of 0.9981. Regarding this, the FCM-ANFIS is a good candidate to calculate the critical cutting speed. To the best of the authors' knowledge, this is the first study in the literature that uses a machine learning tool to predict shear localization.
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    Article
    A boundary value problem for second-order nonlinear difference equations on the integers
    (Cambridge Univ Press, 2005) Dal, F; Guseinov, GS
    In this study, we are concerned with a boundary value problem (BVP) for nonlinear difference equations on the set of all integers Z, under the assumption that the left-hand side is a second-order linear difference expression which belongs to the so-called Weyl-Hamburger limit-circle case. The BVP is considered in the Hilbert space l(2) and includes boundary conditions at infinity. Existence and uniqueness results for solution of the considered BVP are established.
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    Article
    Citation - WoS: 2
    Citation - Scopus: 2
    A Note on Public Investment, Public Debt, and Macroeconomic Performance
    (Cambridge Univ Press, 2011) Ismihan, Mustafa; Ozkan, F. Gulcin
    This paper provides an assessment of public capital spending within a macroeconomic policy model with explicit monetary and fiscal interactions, in contrast to most of the existing analyses of public investment that utilize "real" general equilibrium models. As such, we are able to consider the interactions of public investment with inflation, taxation, and public debt. Our results indicate that a clear trade-off exists between the costs and benefits of public investment, as is the case in the existing literature. However, the use of a monetary-fiscal policy model rather than a "real" general equilibrium one enables us to trace the macroeconomic channels including monetary ones through which these costs and benefits are transmitted to the rest of the economy. To the extent that these costs and benefits vary between countries, our results provide a potential explanation for the mixed empirical findings on the real effects of public capital spending.
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    Book Part
    Citation - WoS: 4
    Continued Fractions: Real Numbers
    (Cambridge Univ Press, 2008) Khrushchev, Sergey
    [No Abstract Available]
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    Book Part
    p-fractions
    (Cambridge Univ Press, 2008) Khrushchev, Sergey
    [No Abstract Available]
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    Article
    Citation - WoS: 14
    Citation - Scopus: 17
    Hybrid Nanocomposites of Elastomeric Polyurethane Containing Halloysite Nanotubes and Poss Nanoparticles: Tensile, Hardness, Damping and Abrasion Performance
    (Cambridge Univ Press, 2020) Mohamed, Salma Taher; Tirkes, Seha; Akar, Alinda Oyku; Tayfun, Umit
    Thermoplastic polyurethane (TPU) matrix was reinforced with polyhedral oligomeric silsesquioxane (POSS) and halloysite nanotubes (HNT), both separately and combined. Composite samples were fabricated using a melt-compounding method. Characterization of the composites obtained was performed via tensile and hardness tests, melt-flow index measurements (MFI), abrasion tests, dynamic mechanical analysis (DMA) and scanning electron microscopy (SEM) to investigate the mechanical performance, flow behaviour, tribological characteristics, thermo-mechanical response and morphological properties. The greatest tensile strength value was obtained for the smallest HNT content. Further addition of HNT resulted in agglomerations for both POSS and HNT particles. The shore hardness of TPU was enhanced by filler inclusions. The TPU/POSS composites displayed significant improvement in terms of abrasion resistance compared to TPU at lower loading levels. The DMA study showed that composites containing 0.5% POSS and 1.0% HNT displayed the greatest storage modulus. The glass-transition temperature of TPU shifted to smaller values with the addition of both nanoparticles. The HNT inclusions increased the MFI value of TPU because of their large aspect ratio. Homogeneous mixing of nanoparticles in the TPU matrix was confirmed by a SEM study of the composites. Their dispersion decreased as the concentrations of POSS and HNT increased. An adjuvant effect of POSS with HNT was achieved in their hybrid composites.