We consider the problem of approximating the output of a parametric electromagnetic field model in the presence of a large number of uncertain input parameters. Given a sufficiently smooth output with respect to the input parameters, such problems are often tackled with interpolation-based approaches, such as the stochastic collocation method on tensor-product or isotropic sparse grids. Due to ...

The abstract interpolation problem (AIP) in the Schur class was posed V. Katznelson, A. Kheifets and P. Yuditskii in 1987 as an extension of the V.P. Potapov’s approach to interpolation problems. In the present paper an analog of the AIP for Nevanlinna classes is considered. The description of solutions of the AIP is reduced to the description of L-resolvents of some model symmetric operator as...

Particle-in-cell codes are the most widely used simulation tools for kinetic studies of ultra-intense laser-plasma interactions. Using motion a single electron in plane electromagnetic wave as benchmark problem, we show surprising deterioration numerical accuracy PIC algorithm with increasing normalized amplitude typical time-step and grid sizes. Two significant sources errors identified: stron...

It is typical in edge and corner detection applications to examine a single scale or to consider some space of scales in the image without knowing which scale is appropriate for each location in the image. However, many images contain a wide variation in the distance to the scene points, and thus features of the same size can appear at greatly differing scales in the image. We present a method ...

preprint numerics no. 3/2011 norwegian university of science and technology trondheim, norway In this paper, we introduce two parameter multi-domain " hp " techniques for the empirical interpolation method (EIM). In both approaches, we construct a partition of the original parameter domain into parameter subdomains: h-refinement. We apply the standard EIM independently within each subdomain to ...

In this paper, we first introduce a 3D morphing method for landmark-based volume deformation, using various scattered data interpolation schemes. Qualitative and speed comparisons are also made for different interpolation schemes. To efficiently render the volume morphing process, a new deformable volume rendering algorithm is presented. The algorithm renders the deformed volume directly withou...

The application of Orthogonal Space-Time Block Codes (O-STBC) as the encoding scheme in the presence of “non-quasi-static” fading was considered. A simple and efficient adaptive method of channel estimation based on the interpolation of estimates acquired at the pre-amble and post-amble of framed blocks of information is developed. Moreover, the proposed method is proven, both theoretically and...

Frame rate up-conversion is useful for low frame rate pictures such as movie. In case of conversion, basic motion compensation causes gap at covered area and uncovered area. To avoid the gap, we propose the motion compensation centered at the position of target. Fully motion compensated interpolation is possible in this method. To realize this, error normalizing by block activity is used for mo...

In the context of mesh adaptation, Riemannian metric spaces have been used to prescribe orientation, density and stretching of anisotropic meshes. But, such structures are only considered to compute lengths in adaptive mesh generators. In this article, a Riemannian metric space is shown to be more than a way to compute a length. It is proven to be a reliable continuous mesh model. In particular...

Natural indexing is an application-oriented description method for nite element meshes. This work describes how the main parts of an adaptive multilevel method for linear triangular nite element methods can be expressed within the framework of natural indexing. Particular emphasis is on the expression of operations that involve hierarchies of meshes such as adaptive re nement, hierarchic coarse...