WoS İndeksli Yayınlar Koleksiyonu
Permanent URI for this collectionhttps://hdl.handle.net/20.500.12573/394
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Conference Object Twist-Bend Instability of a Cantilever Beam Subjected to an End Load via Homotopy Perturbation Method(Amer Inst Physics, 2018) Yucesoy, Ahmet; Coskun, Safa Bozkurt; Atay, Mehmet Tarik; Cesoy, AhmetIn this article, twist-bend buckling analysis of a cantilever beam subjected to a concentrated end load is conducted using Homotopy Perturbation Method (HPM). Even in the linear stability analysis, obtaining an exact solution for some cases is not an easy task. However, by the use of HPM this difficulty can be overcome easily. This issue is presented with a case study and the results show that HPM can be used successfully in the analysis of twist-bend buckling of beams.Conference Object Citation - WoS: 2Citation - Scopus: 1The Numerical Solutions for Stiff Ordinary Differential Equations by Using Interpolated Variational Iteration Method With Comparison to Exact Solutions(Amer Inst Physics, 2018) Ciftci, Cihan; Cayci, Hatice Sinem Sas; Atay, Mehmet Tarik; Toker, Batuhan; Guncan, Berkay; Yildirim, Afsin TalhaRecently proposed Interpolated Variational Iteration Method (IVIM) is used to find numerical solutions of stiff ordinary differential equations for both linear and nonlinear problems. The examples are given to illustrate the accuracy and effectiveness of IVIM method and IVIM results are compared with exact results. In recent analytical approximate methods based studies related to stiff ordinary differential equations, problems were solved by Adomian Decomposition Method and VIM and Homotopy Perturbation Method, Homotopy Analysis Method etc. In this study comparisons with exact solutions reveal that the Interpolated Variational Iteration Method (IVIM) is easy to implement. In fact, this method is promising methods for various systems of linear and nonlinear stiff ordinary differential equations as an initial value problem. Furthermore, IVIM is giving very satisfactory solutions when compared to exact solutions for nonlinear cases depending on the stiffness ratio of the stiff system to be solved.Article Citation - WoS: 35Citation - Scopus: 42The Photoionization Cross Section of a Hydrogenic Impurity in a Multi-Layered Spherical Quantum Dot(Amer Inst Physics, 2012-04-15) Sahin, Mehmet; Tek, Firdes; Erdinc, Ahmet; Erdin, AhmetIn this study, we have investigated the photoionization cross section of an on-center hydrogenic impurity in a multi-layered spherical quantum dot. The electronic energy levels and their wave functions have been determined fully numerically by shooting method. Also, we have calculated the binding energy of the impurity by using these energy values. The photoionization cross section has also been computed as a function of the layer thickness and normalized photon energies. We have discussed in detail the possible physical reasons behind the changes in the binding energies and photoionization cross section. It is observed that both the binding energies and the photoionization cross sections depend strongly on the layer thickness and photon energies. (C) 2012 American Institute of Physics. [http://dx.doi.org/10.1063/1.4705410]Article Citation - WoS: 68Citation - Scopus: 76The Inter-Sublevel Optical Properties of a Spherical Quantum Dot-Quantum Well With and Without a Donor Impurity(Amer Inst Physics, 2012-09-01) Tas, Hatice; Sahin, MehmetIn this study, we have investigated the inter-sublevel optical properties of a core/shell/well/shell spherical quantum dot (QD) with the form of quantum dot-quantum well heterostructure. In order to determine the energy eigenvalues and corresponding wave functions, the Schrodinger equation has been solved full numerically by using shooting method in the effective mass approximation for a finite confining potential. The inter-sublevel optical absorption and the oscillator strength between ground (1 s) and excited (1 p) states have been examined based on the computed energies and wave functions. Also, the effect of a hydrogenic donor impurity, located at the center of the multi-shell spherical quantum dot (MSQD), has been researched for different core radii (R-1), shell thicknesses (T-s), and well widths (T-w) in certain potential. It is observed that the oscillator strengths and the absorption coefficients are strongly depend on the core radii and layer thicknesses of the MSQD. (C) 2012 American Institute of Physics. [http://dx.doi.org/10.1063/1.4751483]Article Citation - WoS: 15Citation - Scopus: 15The Electronic Properties of a Two-Electron Multi-Shell Quantum Dot-Quantum Well Heterostructure(Amer Inst Physics, 2013-07-24) Aydin, Rasit; Sahin, MehmetA detailed investigation of the electronic properties of a double electron in a core/shell/well/shell quantum dot heterostructure has been systematically studied for cases with and without an on-center donor impurity. For this purpose, the Poisson-Schrodinger equations have been solved self-consistently in the frame of the single band effective mass approximation and Hartree treatment. The variation of the binding energies of negatively charged donor impurity (D-) have been examined for different core radii, shell thicknesses, and well widths. The results obtained have been presented comparatively as a function of layer thicknesses and probable physical reasons behind in their behavior have been discussed. (C) 2013 AIP Publishing LLC.Article Citation - WoS: 56Citation - Scopus: 61The Electronic Properties of a Core/Shell Spherical Quantum Dot With and Without a Hydrogenic Impurity(Amer Inst Physics, 2012-04-15) Tas, Hatice; Sahin, MehmetIn this study, we have performed a detailed investigation of the electronic properties of a core/shell/well/shell multilayered spherical quantum dot, such as energy eigenvalues, wave functions, electron probability distribution, and binding energies. The energy eigenvalues and their wave functions of the considered structure have been calculated for cases with and without an on-center impurity. For this purpose, the Schrodinger equation has been numerically solved by using the shooting method in the effective mass approximation for a finite confining potential. The electronic properties have been examined for different core radii, barrier thicknesses, and well widths in a certain potential. The results have been analyzed in detail as a function of the layer thicknesses and their physical reasons have been interpreted. It has been found that the electronic properties are strongly dependent on the layer thicknesses. (C) 2012 American Institute of Physics. [http://dx.doi.org/10.1063/1.3702874]Conference Object Target Attractor Tracking of Relative Phase in Bosonic Josephson Junction(Amer Inst Physics, 2016) Borisenok, SergeyThe relative phase of Bosonic Josephson junction in the Josephson regime of Bose-Hubbard model is tracked via the target attractor ('synergetic') feedback algorithm with the inter-well coupling parameter presented as a control function. The efficiency of our approach is demonstrated numerically for Gaussian and harmonic types of target phases.Article Citation - WoS: 14Citation - Scopus: 16TD-DFTB Study of Optical Properties of Silver Nanoparticle Homodimers and Heterodimers(Amer Inst Physics, 2020-10-14) Liu, Zhen; Alkan, Fahri; Aikens, Christine M.The absorption spectra for face-centered cubic nanoparticle dimers at various interparticle distances are investigated using time-dependent density functional tight binding. Both homodimers and heterodimers are investigated in this work. By studying nanoparticles at various interparticle distances and analyzing their vertical excitations, we found that as the interparticle distance decreases, a red shift arises from contributions of the transition dipole moment that are aligned along the z-axis with nondegenerate features; blue shifts occur for peaks that originate from transition dipole moment components in the x and y directions with double degeneracy. When the nanoparticles are similar in size, the features in the absorption spectra become more sensitive to the interparticle distances. The best-fit curves from vertical excitation energy in the form of AR(-b) for Delta E-redshift/Delta E-blueshift vs R are determined. In this way, we determined trends for absorption peak shifts and how these depend on the interparticle distance.Conference Object Statistical Approach for Table Tennis Athletes' Success(Amer Inst Physics, 2018) Goren, Selcuk; Gulbahar, Ibrahim Tumay; Pinar, Muhammed SafakThis report summarizes the statistical modeling and analysis results associated with the athletes' success and athletes' features. Main purpose of this report is to find any relation between athletes' success and their features. As a tool of creating correlation regression is used with SPSS.Conference Object Citation - WoS: 17Citation - Scopus: 21Sol-Gel Applications for Ceramic Membrane Preparation(Amer Inst Physics, 2017) Erdem, I.Ceramic membranes possessing superior properties compared to polymeric membranes are more durable under severe working conditions and therefore their service life is longer. The ceramic membranes are composed of some layers. The support is the layer composed of coarser ceramic structure and responsible for mechanical durability under filtration pressure and it is prepared by consolidation of ceramic powders. The top layer is composed of a finer ceramic micro-structure mainly responsible for the separation of components present in the fluid to be filtered and sol-gel method is a versatile tool to prepare such a tailor-made ceramic filtration structure with finer pores. Depending on the type of filtration (e.g. micro-filtration, ultra-filtration, nano-filtration) aiming separation of components with different sizes, sols with different particulate sizes should be prepared and consolidated with varying precursors and preparation conditions. The coating of sol on the support layer and heat treatment application to have a stable ceramic micro-structure are also important steps determining the final properties of the top layer. Sol-gel method with various controllable parameters (e.g. precursor type, sol formation kinetics, heat treatment conditions) is a practical tool for the preparation of top layers of ceramic composite membranes with desired physicochemical properties.