YÖK Akademik
Permanent URI for this collectionhttps://acikarsiv.thk.edu.tr/handle/123456789/2553
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Publication Higher dimensional Bell-Szekeres metric(American Physical Society (APS), 2003-10-22) M. Gürses; Y. İpekoğlu; A. Karasu; Ç. ŞentürkPublication Using a compound approach based on elaborated neural network for Webometrics: An example issued from the EICSTES project(Springer Science and Business Media LLC, 2004) Jean-Charles Lamirel; Shadi Al Shehabi; Claire Francois; Xavier PolancoPublication New classification quality estimators for analysis of documentary information: Application to patent analysis and web mapping(Springer Science and Business Media LLC, 2004) Jean-Charles Lamirel; Claire Francois; Shadi Al Shehabi; Martial HoffmannPublication A Monte Carlo method for computing the marginal likelihood in nondecomposable Gaussian graphical models(Oxford University Press (OUP), 2005-06-01) Aliye Atay-Kayis; Hélène MassamPublication UHF RF Front-End Circuits in 0.35-μm Silicon on Insulator (SOI) CMOS(Springer Science and Business Media LLC, 2005-12) Ertan Zencir; Te-Hsin Huang; Ahmet Tekin; Numan S. Dogan; Ercument Arvas; Zencir, ErtanPublication Scientific visualization: Analysis, exploration and presentation of tri-axial stress states of Kr+ implanted titanium determined by X-ray diffraction(Elsevier BV, 2007-08) M. Yaman; M. Härting; S. Nsengiyumva; D.T. BrittonPublication A unifying grid approach for solving potential flows applicable to structured and unstructured grid configurations(Elsevier BV, 2008-01) A. Ruhşen Çete; M. Adil Yükselen; Ünver KaynakPublication Three-dimensional surface reconstruction for cartridge cases using photometric stereo(Elsevier BV, 2008-03) Ufuk Sakarya; Uğur Murat Leloğlu; Erol Tunalı; Leloğlu, Uğur MuratPublication Data Fusion of Panoramic Images and Laser Scans for Dynamic Targets Detection(IEEE, 2008-04) Abedallatif Baba; Raja ChatilaPublication Automatic EOG analysis: A first step toward automatic drowsiness scoring during wake-sleep transitions(Springer Science and Business Media LLC, 2008-09) Bruno Jammes; Hassan Sharabty; Daniel EstevePublication Establishing space industry in developing countries: Opportunities and difficulties(Elsevier BV, 2008-12) U.M. Leloglu; E. KocaoglanPublication FT-IR spectra, vibrational assignments, and density functional calculations of imidazo[1,2-a]pyridine molecule and its Zn(II) halide complexes(Springer Science and Business Media LLC, 2009-02-20) Şenay Yurdakul; Serdar Badoğlu; Badoğlu, SerdarPublication All-chalcogenide glass omnidirectional photonic band gap variable infrared filters(AIP Publishing, 2009-03-16) H. Esat Kondakci; Mecit Yaman; Ozlem Koylu; Aykutlu Dana; Mehmet Bayindir; Yaman, MecitWe report on the design, fabrication, and characterization of spatially variable infrared photonic band gap filter that consists of thermally evaporated, high refractive index contrast, amorphous chalcogenide glass multilayers. Due to graded thickness structure, the filter exhibits a position dependent stop band and a cavity mode ranging from 1.8 to 3.4 μm wavelengths. Reflection measurements on the variable filter agree well with theoretical calculations. These results pave the way to low-loss infrared mirrors, filters, spectral imaging, and miniaturized spectrometers at infrared region.Publication Enhancement of H<SUB>2</SUB> Storage in Carbon Nanotubes via Doping with a Boron Nitride Ring(American Scientific Publishers, 2009-04-01) Aytun Koyuncular Onay; Şakir ErkoçPublication Requirements for forming an ‘e-supply chain’(Informa UK Limited, 2009-04-23) Goknur Arzu Akyuz; Mohammad RehanPublication Highly efficient volume generation reservoirs in molecular simulations of gas flows(Elsevier BV, 2009-07) Nevsan Sengil; Firat O. EdisPublication The effects of ureteral obstruction on Cajal-like cells in rats(Elsevier BV, 2009-08) Baris Kuzgunbay; Figen Doran; Yildirim Bayazit; Tahsin Turunc; Nihat Satar; Aliye Atay KayisPublication Supply chain performance measurement: a literature review(Informa UK Limited, 2009-08-25) Goknur Arzu Akyuz; Turan Erman ErkanPublication Atomistic simulation of micro‐scale adiabatic piston problem(Emerald, 2009-10-16) Nevsan Sengil; Firat Oguz EdisPurposeThe purpose of this paper is to demonstrate the utilization of the direct simulation Monte Carlo (DSMC) method for moving‐boundary/deforming‐domain micro‐scale gas flow problems. Furthermore, a hydrodynamic model, proposed in the literature, is used to compare its results with those obtained using the DSMC method.Design/methodology/approachA micro‐scale adiabatic piston problem is analyzed using a parallel DSMC implementation for deforming domains. Initially, pressures at both sides of the piston wall are different. Consequently, frictionless piston moves toward low‐pressure compartment, keeps oscillating from one side to the other. Eventually, the piston reaches the “Mechanical equilibrium” state. Although the temperatures are different, pressures are equal at this state. The unsteady problem is analyzed until it reaches this state. Three test cases, all with the same initial conditions but different piston masses are analyzed. The time variation of the piston position, conditions in the compartments separated by the piston, are presented and compared with the results obtained from a hydrodynamic model proposed in the literature.FindingsThe results show that the DSMC and hydrodynamic results agree for the case where the piston mass is much larger than the mass of the gas inside the cylinder. But for other two cases, where the piston mass is smaller, piston motion, and conditions in the compartments separated by the piston differ for the two methods. This is attributed to the linear velocity distribution assumption of the hydrodynamic model. The DSMC results demonstrate that this assumption is not valid for cases where the piston mass is equal or less than the mass of the gas inside the cylinder.Originality/valueImplementation of the DSMC method for problems with deforming domain is presented and a limitation for applicability of hydrodynamic model for these problems is shown.Publication Comparison of Implicit Time Integration Schemes for Nonlinear Dynamic Problems(ASMEDC, 2010-01-01) Murat DemiralImplicit time integration schemes are used to obtain stable and accurate transient solutions of nonlinear problems. Methods that are unconditionally stable in linear analysis are sometimes observed to have convergence problems as in the case of solutions obtained with a trapezoidal method. On the other hand, a composite time integration method employing a trapezoidal rule and a three-point backward rule sequentially in two half steps can be used to obtain accurate results and enhance the stability of the system by means of a numerical damping introduced in the formulation. To have a better understanding of the differences in the numerical implementation of the algorithms of these two methods, a mathematical analysis of dynamic equilibrium equations is performed. Several practical problems are studied to compare the implicit methods.