Scopus İndeksli Yayınlar Koleksiyonu

Permanent URI for this collectionhttps://hdl.handle.net/20.500.12416/8651

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  • Article
    Citation - WoS: 3
    Citation - Scopus: 3
    On the Characteristic Functions and Dirchlet-Integrable Solutions of Singular Left-Definite Hamiltonian Systems
    (Taylor & Francis Ltd, 2024) Ugurlu, Ekin; Bairamov, Elgiz; Tas, Kenan
    In this work, a singular left-definite Hamiltonian system is considered and the characteristic-matrix theory for this Hamiltonian system is constructed. Using the results of this theory we introduce a lower bound for the number of Dirichlet-integrable solutions. Moreover we share a relation between the kernel of the solution of the nonhomogeneous boundary value problem and the characteristic-matrix.
  • Article
    Citation - WoS: 10
    Citation - Scopus: 8
    Predicting Seismic Damage on Concrete Gravity Dams: a Review
    (Taylor & Francis Ltd, 2024) Arici, Yalin; Soysal, Berat Feyza
    The seismic assessment of concrete gravity dams is a problem of prediction of cracking and the corresponding consequences. With the widespread use of general-purpose finite element programs, the work in the field has shifted towards quantifying the behaviour in a framework for assessment. The nonlinear analysis and coupling with foundation-reservoir interaction, conversely, is still a challenging task. The modelling approach has significant effects on the analysis results and the assessment framework. The field remains an active area for research with many outstanding issues regarding damage quantification and assessment compared to any other major infrastructure component. A comprehensive overview of the seismic assessment of gravity dams is presented in this work with the goal to outline the issues in the field. Different models and modelling choices are compared in the context of damaged state assessment of gravity dams. The links between practical difficulties and theoretical issues are critically discussed. The aleatoric and epistemic uncertainties in the field, and their sources, are presented. Areas of future work are identified for improvement in seismic assessment as well as reducing and quantifying the uncertainties in the prediction of damaged states for concrete gravity dams.
  • Article
    Citation - WoS: 6
    Citation - Scopus: 9
    Applications of the Novel Diamond Alpha Hardy-Copson Type Dynamic Inequalities To Half Linear Difference Equations
    (Taylor & Francis Ltd, 2022) Kaymakcalan, Billur; Kayar, Zeynep
    This paper is devoted to novel diamond alpha Hardy-Copson type dynamic inequalities, which are zeta < 0 complements of the classical ones obtained fort zeta > 1, and their applications to difference equations. We obtain two kinds of diamond alpha Hardy-Copson type inequalities for zeta < 0, one of which is mixed type and established by the convex linear combinations of the related delta and nabla inequalities while the other one is new and is obtained by using time scale calculus rather than algebra. In contrast to the works existing in the literature, these complements are derived by preserving the directions of the classical inequalities. Therefore both kinds of our results unify some of the known delta and nabla Hardy-Copson type inequalities obtained for zeta < 0 into one diamond alpha Hardy-Copson type inequalities and offer new types of diamond alpha Hardy-Copson type inequalities which have the same directions as the classical ones and can be considered as complementary inequalities. Moreover the application of these inequalities in the oscillation theory of half linear difference equations provides several nonoscillation criteria for such equations.
  • Article
    Citation - WoS: 6
    Citation - Scopus: 7
    Crack Width - Seismic Intensity Relationships for Concrete Gravity Dams
    (Taylor & Francis Ltd, 2024) Soysal, Berat Feyza; Arici, Yalin
    Seismic assessment of plain concrete structures like gravity dams is generally conducted based on cracking. The responses of two types of gravity dams, i.e. the conventional and roller compacted concrete (RCC), were investigated in this study using a discrete element tool coupled with special reservoir elements. Using incremental dynamic analysis, the relationship between the seismic intensity measures and crack widths on the U/S face of the monolith was obtained. The damage accumulation on conventional and RCC dams was different: The cumulative cracking on the upstream face of the monolith correlated well to a seismic intensity measure representing base shear.
  • Article
    Citation - WoS: 11
    Citation - Scopus: 11
    A Novel Radial Basis Procedure for the Sirc Epidemic Delay Differential Model
    (Taylor & Francis Ltd, 2023) Baleanu, Dumitru; Mallawi, Fouad Othman; Ullah, Malik Zaka; Sabir, Zulqurnain
    The purpose of this work is to construct a reliable stochastic framework for solving the SIRC delay differential epidemic system, i.e. SIRC-DDES that is based on the coronavirus dynamics. The design of radial basis (RB) transfer function with the optimization of Bayesian regularization neural network (RB-BRNN) is presented to solve the SIRC-DDES. The SIRC-DDES is classified into susceptible $ S(x) $ S(x), infected $ I(x) $ I(x), recovered $ R(x) $ R(x) and cross-immune $ C(x) $ C(x). The exactness of the RB-BRNN is performed for three cases of SIRC-DDES by using the performances of the obtained and reference results. The mean square error is reduced by using the training, testing and substantiation performances with the reference solutions. The small values of the absolute error around 10-07 to 10-08 and different statistical operator performances based on the error histogram values, transitions of state investigations, correlation and regression tests also approve the accuracy of the proposed technique.
  • Article
    Citation - WoS: 3
    Citation - Scopus: 3
    A New Insight To the Hamiltonian Systems With a Finite Number of Spectral Parameters
    (Taylor & Francis Ltd, 2023) Ugurlu, Ekin
    In this article, we introduce a new first-order differential equation containing a finite number of spectral parameters and some results on the solutions of this equation. In particular, with the aid of the nested-circles approach we share a lower bound for the number of linearly independent square-integrable solutions of the equation. We share some limit-point criterias. Moreover, we show that some known and unknown scalar and matrix differential equations can be embedded into this new first-order equation. Using the obtained results we present some additional results for some system of scalar multiparameter differential equations. Finally, we share some relations between the characteristic function of a regular boundary-value problem and the kernel of related integral operator.
  • Article
    Citation - WoS: 20
    Citation - Scopus: 22
    A High-Order Unconditionally Stable Numerical Method for a Class of Multi-Term Time-Fractional Diffusion Equation Arising in the Solute Transport Models
    (Taylor & Francis Ltd, 2023) Khan, Arshad; Baleanu, Dumitru; Alam, Mohammad Prawesh
    In this paper, we study a high-order unconditionally stable numerical method to approximate the class of multi-term time-fractional diffusion equations. This type of problem appears in the modelling of transport of certain quantities such as heat, mass, energy, solutes in ground water and soils. The multi-term time-fractional derivative is approximated by using the Crank-Nicolson method for the Caputo's time derivative. The space derivative is approximated by using the collocation method based on quintic B-spline basis functions. We have established the stability and convergence analysis of the proposed numerical scheme thoroughly, and it is shown that the order of convergence in space variable is almost four and in the time variable is O (Delta t(2-max{gamma,gamma i})). To prove the accuracy and efficiency of the developed method, we consider four numerical examples and perform the numerical simulation. The developed algorithm works well andvalidate the theoretical results. The developed method is fourth-order convergent in the space variable, which is almost two orders of magnitude higher than the other spline collocation methods.
  • Article
    Citation - WoS: 16
    Citation - Scopus: 16
    Novel Bond-Slip Model Between Concrete and Angular Cfrp Fan Type Anchoraged Cfrp Strip
    (Taylor & Francis Ltd, 2022) Ghoroubi, Rahim; Mercimek, Omer; Sakin, Shaimaa; Anil, Ozgur
    One of the most important design approaches in the repairing/strengthening details is using CFRP (Carbon Fiber Reinforced Polymer) to delay the debonding of the CFRP strips/plates from the surface to take full advantage of the CFRP reinforcement. Compared to non-anchored strips, research studies regarding bond-slip models developed for fan type CFRP anchors and anchored CFRP strips to strengthen details are limited in the related literature review. However, in studies on this subject, anchors are placed at 90 degrees to the axial tensile force applied to the CFRP strips. The ultimate load-bearing capacity and bond-slip models of CFRP strips with the different angled CFRP fan type anchor under axial tensile force have not been found in the literature review. Within the study's scope, 28 angled CFRP strip test specimens were produced and then tested under the effect of monotonically increasing axial tensile force with an experimental setup designed by the authors. The variables examined in this study were the concrete compressive power, the CFRP strip's width, the number of the CFRP anchor fan type, and the angle of the anchor placed on the CFRP strip. As a result of the study, an equation was proposed for calculating the ultimate load-bearing capacity of angled anchored CFRP strips and angled anchored CFRP strips. Finally, a new proposal for the bond-slip model was developed. It is thought that the new interface bond-slip model developed for CFRP strips with different angles will make an important contribution to the literature. It can be used in finite element analysis to realistically analyze the capacities and load-displacement behavior of reinforced concrete structural elements by strengthening such strips.
  • Article
    Citation - WoS: 11
    Citation - Scopus: 10
    Ranking Using Promethee When Weights and Thresholds Are Imprecise: a Data Envelopment Analysis Approach
    (Taylor & Francis Ltd, 2022) Eryilmaz, Utkan; Karasakal, Orhan; Karasakal, Esra
    Multicriteria decision making (MCDM) provides tools for the decision makers (DM) to solve complex problems with multiple conflicting criteria. Scalarization of criteria values requires using weights for criteria. Determining weights creates controversy as they are influential on the final ranking and challenges the DM as they are hard to elicit. PROMETHEE method is widely used in MCDM for ranking the alternatives and appropriate in situations when there is limited information on the preference structure of the DM. The DM should provide exact values for parameters such as criteria weights and thresholds of preference functions. Data Envelopment Analysis (DEA) is used for measuring the relative efficiency of alternatives in a non-parametric way without requiring any weight input. In this study, we propose two novel PROMETHEE based ranking approaches that address the determination of weight and threshold values by using an approach inspired by DEA. The first approach can deal with imprecise specification of criteria weights, and the second approach can utilize both imprecise weights and thresholds. The proposed approaches provide the DM substantial flexibility on the required level of information on those parameters. An illustrative example and a real-life case study are presented to show the utility of the proposed approaches.
  • Article
    Citation - WoS: 1
    Citation - Scopus: 1
    On the Non-Commutative Neutrix Product of the Distributions X<sup>-r</Sup>+ Ln<sup>p</Sup> X+ and X<sup>μ</Sup>+ln<sup>q< X+
    (Taylor & Francis Ltd, 2006) Tas, Kenan; Fisher, Brian
    Let f and g be distributions and g(n) = (g*delta(n))(x), where delta(n)(x ) is a certain sequence converging to the Dirac delta-function. The non-commutative neutrix product f o g of f and g is defined to be the neutrix limit of the sequence {fg(n) }, provided its limit h exists in the sense that [GRAPHICS] for all functions phi in D. It is proved that (x(+)(-r) ln(p) x(+)) o (x(+)(mu) ln(q) x(+)) = x(+)(-r+mu) ln(p+q) x(+) (x(-)(-r) ln(p) (x)-) o (x(-)(mu) ln(q) x(-)) = x(-)(-r+mu) ln(p+q) x(-) for mu < r - 1;mu not equal 0, +/- 1, +/- 2,..., r = 1,2,..., and p, q = 0, 1, 2,....