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Most applications of the publicly released Gravity Recovery and Climate Experiment monthly gravity field models require the application of a spatial filter to help suppressing noise and other systematic errors present in the data. The most common approach makes use of a simple Gaussian averaging process, which is often combined with a 'destriping' technique(More)
This article discusses the high-performance parallel implementation of the computation and updating of QR factorizations of dense matrices, including problems large enough to require out-of-core computation, where the matrix is stored on disk. The algorithms presented here are scalable both in problem size and as the number of processors increases.(More)
We study the high-performance implementation of the inversion of a Symmetric Positive Definite (SPD) matrix on architectures ranging from sequential processors to Symmetric MultiProcessors to distributed memory parallel computers. This inversion is traditionally accomplished in three “sweeps”: a Cholesky factorization of the SPD matrix, the(More)
This study explores an approach that simultaneously estimates Antarctic mass balance and glacial isostatic adjustment (GIA) through the combination of satellite gravity and altimetry data sets. The results improve upon previous efforts by incorporating a firn densification model to account for firn compaction and surface processes as well as reprocessed(More)
We present families of algorithms for operations related to the computation of the inverse of a Symmetric Positive Definite (SPD) matrix: Cholesky factorization, inversion of a triangular matrix, multiplication of a triangular matrix by its transpose, and one-sweep inversion of an SPD matrix. These algorithms are systematically derived and implemented via(More)
Article is made available in accordance with the publisher's policy and may be subject to US copyright law. Please refer to the publisher's site for terms of use. The MIT Faculty has made this article openly available. Please share how this access benefits you. Your story matters. ABSTRACT GEOScan is a grassroots effort, proposed as globally networked(More)
The paper presents the latest results in the design of FAST-D, the Dutch micro-satellite for the Dutch–Chinese FAST (Formation for Atmospheric Science and Technology demonstration) formation flying mission. Over the course of the 2.5 year mission, the two satellites, FAST-D and FAST-T, will demonstrate various new technologies and perform observations of(More)
Acknowledgements This PhD thesis and the underlying research would not have been possible without the help of many people. First and foremost I want to thank my supervisor and promotor, Prof. Roland Klees, for his help and guidance during the five years of research. He was always available regardless of his busy schedule, and managed to keep me on track(More)
Soil moisture is important for the Volta Basin. However, in-situ measurements of soil moisture in the Volta Basin are scarce, only remote sensing observations are available. Remote sensing observations are also provided with limited temporal and spatial resolutions. Also capabilities of the sensors are limited (e.g measuring soil moisture limited in shallow(More)