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We consider time-dependent thermal fluid structure interaction. The respective models are the compressible Navier–Stokes equations and the nonlinear heat equation. A partitioned coupling approach via a Dirichlet–Neumann method and a fixed point iteration is employed. As a reference solver, a previously developed efficient time-adaptive higher-order time integration scheme is used. To improve on t
Microstructural information over an entire sample is important to understand the macroscopic behaviour of materials. X-ray scattering tensor tomography facilitates the investigation of the microstructural organisation in statistically large sample volumes. However, established acquisition protocols based on scanning small-angle X-ray scattering and X-ray grating interferometry inherently require l
Given a set V of n points in R-d and a real constant t > 1, we present the first O(n log n)-time algorithm to compute a geometric t-spanner on V. A geometric t-spanner on V is a connected graph G = ( V, E) with edge weights equal to the Euclidean distances between the endpoints, and with the property that, for all u, v is an element of V the distance between u and v in G is at most t times the Euc
In synthetic aperture radar one wishes to reconstruct the reflectivity function of a region on the ground from a set of radar measurements taken at several angles. The ground reflectivity is found by interpolating measured samples, which typically lie on a polar grid in frequency space, to an equally spaced rectangular grid in frequency space, then computing an inverse Fourier transform. The class
We consider the problem of computing the product of two n×n Boolean matrices A and B. For an n×n Boolean matrix C, let GC be the complete weighted graph on the rows of C where the weight of an edge between two rows is equal to its Hamming distance, i.e., the number of entries in the first row having values different from the corresponding entries in the second one. Next, letMWT(C) be the weight of a
The thesis deals with circuit-level aspects of CMOS buffer SRAMs where the data throughput rate is a more important metric than access time or storage capacity. One aspect is the increased write cycle related power consumption that is the consequence of a high write ratio combined with a long word-length. That is addressed through the invention of a new bit-line operation mode which allows lower
We use randomness to exploit the potential sparsity of the Boolean matrix product in order to speed up the computation of the product. Our new fast outputsensitive algorithm for Boolean matrix product and its witnesses is randomized and provides the Boolean product and its witnesses almost certainly. Its worst-case time performance is expressed in terms of the input size and the number of non-zero
This paper describes a fast algorithm for topology independent tracking of moving interfaces under curvature- and velocity field-dependent speed laws. This is usually done in the level set framework using the narrow-band algorithm, which accurately solves the level set equation but is too slow to use in real-time or near real-time image segmentation applications. In this paper we introduce a fast
We use randomness to exploit the potential sparsity of the Boolean matrix product in order to speed up the computation of the product. Our new fast output-sensitive algorithm for Boolean matrix product and its witnesses is randomized and provides the Boolean product and its witnesses almost certainly. Its worst-case time performance is expressed in terms of the input size and the number of non-zer
This paper presents a novel polynomial constraint for homographies compatible with the general planar motion model. In this setting, compatible homographies have five degrees of freedom-instead of the general case of eight degrees of freedom-and, as a consequence, a minimal solver requires 2.5 point correspondences. The existing minimal solver, however, is computationally expensive, and we propose
Increasingly fine-grained cloud billing creates incentives to review the software execution footprint in virtual environments. For example, virtual execution environments move towards lower overhead: from virtual machines to containers, unikernels, and serverless cloud computing. However, the execution footprint of security components in virtualized environments has either remained the same or eve
The Fourier slice theorem for the standard Radon transform generalizes to a Laplace counterpart when considering the exponential Radon transform. We show how to use this fact in combination with algorithms for the unequally spaced fast Laplace transform to construct fast and accurate methods for computing both the forward exponential Radon transform and the corresponding back-projection operator.
Fingerprint recognition has become a popular authentication method in modern smartphones, replacing traditional passwords and PINs. However, smartphone fingerprint sensors are small and capture only partial fingerprints with limited resolution. Combined with varying image quality and inconsistent finger placement, multiple images must be stored per user to ensure reliable authentication. During ve
