Browsing by Keywords "Approximation algorithms"
Now showing items 1-20 of 24
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Algebraic acceleration and regularization of the source reconstruction method with the recompressed adaptive cross approximation
(IEEE, 2014)We present a compression algorithm to accelerate the solution of source reconstruction problems that are formulated with integral equations and defined on arbitrary three-dimensional surfaces. This compression technique ... -
An algorithm and a core set result for the weighted euclidean one-center problem
(Institute for Operations Research and the Management Sciences (I N F O R M S), 2009)Given a set A of m points in n-dimensional space with corresponding positive weights, the weighted Euclidean one-center problem, which is a generalization of the minimum enclosing ball problem, involves the computation of ... -
An approximation algorithm for computing the visibility region of a point on a terrain and visibility testing
(IEEE, 2014-01)Given a terrain and a query point p on or above it, we want to count the number of triangles of terrain that are visible from p. We present an approximation algorithm to solve this problem. We implement the algorithm and ... -
Computing minimum-volume enclosing axis-aligned ellipsoids
(Springer, 2008)Given a set of points S = {x1 ,..., xm}⊂ ℝn and ε>0, we propose and analyze an algorithm for the problem of computing a (1+ε)-approximation to the minimum-volume axis-aligned ellipsoid enclosing S. We establish that our ... -
Çok kullanıcılı çok antenli sistemlerde iş birlikli iletim
(IEEE, 2008-04)Bu çalışmada işbirlikli, çok kullanıcılı, ve çok antenli bir haberleşme sisteminde telsiz erişim terminallerinin en iyi veri iletimi tekniğine ortaklaşa karar vermeleri problemini inceliyoruz. Burada pek çok çalışmadan ... -
Effective preconditioners for large integral-equation problems
(IET, 2007-11)We consider effective preconditioning schemes for the iterative solution of integral-equation methods. For parallel implementations, the sparse approximate inverse or the iterative solution of the near-field system enables ... -
Heat transfer through dipolar coupling: Sympathetic cooling without contact
(American Physical Society, 2016)We consider two parallel layers of dipolar ultracold Fermi gases at different temperatures and calculate the heat transfer between them. The effective interactions describing screening and correlation effects between the ... -
Identification and elimination of interior points for the minimum enclosing ball problem
(Society for Industrial and Applied Mathematics, 2008)Given A := {a1,...,am} C ℝn, we consider the problem of reducing the input set for the computation of the minimum enclosing ball of A. In this note, given an approximate solution to the minimum enclosing ball problem, we ... -
Joint mixability of some integer matrices
(Elsevier B.V.Elsevier BV, 2016)We study the problem of permuting each column of a given matrix to achieve minimum maximal row sum or maximum minimal row sum, a problem of interest in probability theory and quantitative finance where quantiles of a random ... -
A linearly convergent linear-time first-order algorithm for support vector classification with a core set result
(Institute for Operations Research and the Management Sciences (I N F O R M S), 2011)We present a simple first-order approximation algorithm for the support vector classification problem. Given a pair of linearly separable data sets and. ε (0,1), the proposed algorithm computes a separating hyperplane whose ... -
Minimizing schedule length on identical parallel machines: an exact algorithm
(Bilkent University, 1991)The primary concern of this study is to investigate the combinatorial aspects of the single-stage identical parallel machine scheduling problem and to develop a computationally feasible branch and bound algorithm for its ... -
Minimum maximum-degree publish-subscribe overlay network design
(IEEE, 2011)Designing an overlay network for publish/subscribe communication in a system where nodes may subscribe to many different topics of interest is of fundamental importance. For scalability and efficiency, it is important to ... -
On Khachiyan's algorithm for the computation of minimum-volume enclosing ellipsoids
(Elsevier, 2007)Given A {colon equals} { a1, ..., am } ⊂ Rd whose affine hull is Rd, we study the problems of computing an approximate rounding of the convex hull of A and an approximation to the minimum-volume enclosing ellipsoid of A. ... -
On the minimum volume covering ellipsoid of ellipsoids
(Society for Industrial and Applied Mathematics, 2006)Let S denote the convex hull of m full-dimensional ellipsoids in ℝn. Given ε > 0 and δ > 0, we study the problems of computing a (1 + ε)-approximation to the minimum volume covering ellipsoid of S and a (1 + δ)n-rounding ... -
Online Contextual Influence Maximization in social networks
(Institute of Electrical and Electronics Engineers Inc., 2017)In this paper, we propose the Online Contextual Influence Maximization Problem (OCIMP). In OCIMP, the learner faces a series of epochs in each of which a different influence campaign is run to promote a certain product in ... -
Online contextual influence maximization with costly observations
(IEEE, 2019-06)In the online contextual influence maximization problem with costly observations, the learner faces a series of epochs in each of which a different influence spread process takes place over a network. At the beginning of ... -
Online solutions for scalable file server systems
(ACM, 2006)We propose three online algorithms for scalable file server systems. A scalable file server is expected to provide rather stable services while the numbers of users, tasks, and data volumes keep increasing. One of the ... -
Parallel preconditioners for solutions of dense linear systems with tens of millions of unknowns
(2007-11)We propose novel parallel preconditioning schemes for the iterative solution of integral equation methods. In particular, we try to improve convergence rate of the ill-conditioned linear systems formulated by the electric-field ... -
Phase diagram and dynamics of Rydberg-dressed fermions in two dimensions
(American Physical Society, 2017)We investigate the ground-state properties and the collective modes of a two-dimensional two-component Rydberg-dressed Fermi liquid in the dipole-blockade regime. We find instability of the homogeneous system toward ... -
The solution of large EFIE problems via preconditioned multilevel fast multipole algorithm
(Institution of Engineering and Technology, 2007)We propose an effective preconditioning scheme for the iterative solution of the systems formulated by the electric- field integral equation (EFIE). EFIE is notorious for producing difficult-to-solve systems. Especially, ...