We classify the resolution graphs of weighted homogeneous surface singularities which admit rational homology disk smoothings. The nonexistence of rational homology disk smoothings is shown by symplectic geometric methods, while the existence is verified via smoothings of negative weight.


Linear and nonlinear intersubband optical absorptions in an asymmetric rectangular quantum well
Karabulut, I.; Atav, U.; Safak, H.; Tomak, Mehmet (2007-02-01)
The linear and nonlinear intersubband optical absorptions in AlxlGa1-xlAs/GaAs/AlxrGa1-xrAs asymmetric rectangular quantum well are studied within the framework of the density matrix formalism. We have calculated the electron energy levels and the envelope wave functions using the effective mass approach. In addition, we have obtained an expression for saturation intensity. It is shown that the parameters such as asymmetry and width of potential well not only shift the peak positions in absorption spectrum ...
Numerical method for optimizing stirrer configurations
Schafer, M; Karasözen, Bülent; Uludağ, Yusuf; YAPICI, KEREM; Uğur, Ömür (2005-12-15)
A numerical approach for the numerical optimization of stirrer configurations is presented. The methodology is based on a parametrized grid generator, a flow solver, and a mathematical optimization tool, which are integrated into an automated procedure. The flow solver is based on the discretization of the Navier-Stokes equations by means of the finite-volume method for block-structured, boundary-fitted grids with multi-grid acceleration and parallelization by grid partitioning. The optimization tool is an ...
Multi-image region growing for integrating disparity maps
Leloglu, UĞUR MURAT; Halıcı, Uğur (1999-01-01)
In this paper, a multi-image region growing algorithm to obtain planar 3-D surfaces in the object space from multiple dense disparity maps, is presented. A surface patch is represented by a plane equation and a set of pixels in multiple images. The union of back projections of all pixels in the set onto the infinite plane, forms the surface patch. Thanks to that hybrid representation of planar surfaces, region growing (both region aggregation and region merging) is performed on all images simultaneously. Pl...
Singular inverse Sturm-Liouville problems with Hermite pseudospectral methods
Altundag, H.; Taşeli, Hasan (2021-10-01)
A numerical approximation to recover certain symmetric potentials in the singular inverse Sturm-Liouville problems over (-infinity,infinity) is presented. A Hermite pseudospectral method is employed to cope with the corresponding direct problem on the real line, which is encountered in the iterative procedure proposed for the inverse problem. The usual but unwelcome ill-posed structure of the resulting numerical algorithm has been treated to some extent by the help of a flexible optimization parameter and r...
Pseudospin and spin symmetry in Dirac-Morse problem with a tensor potential
AYDOĞDU, OKTAY; Sever, Ramazan (Elsevier BV, 2011-09-14)
Under the conditions of the pseudospin and spin symmetry, approximate analytical solutions of the Dirac-Morse problem with Coulomb-like tensor potential are presented. The energy eigenvalue equations are found and corresponding radial wave functions are obtained in terms of confluent hypergeometric functions. The energy eigenvalues are calculated numerically in the absence and presence of the tensor potential. We also investigate the contribution of the potential parameters to the energy splitting of the ps...
Citation Formats
M. L. Bhupal, “WEIGHTED HOMOGENEOUS SINGULARITIES AND RATIONAL HOMOLOGY DISK SMOOTHINGS,” AMERICAN JOURNAL OF MATHEMATICS, pp. 1259–1297, 2011, Accessed: 00, 2020. [Online]. Available: https://hdl.handle.net/11511/35861.