Hierarchically semiseparable (HSS) matrix algorithms are emerging techniques in constructing the superfast direct solvers for both dense and sparse linear systems. Here, we develope a set of novel parallel algorithms for the key HSS operations that are used for solving large linear systems. These include the parallel rank-revealing QR factorization, the HSS constructions with hierarchical compr...

The balance between strength and plasticity has always been an urgent problem for researchers to solve. In this experiment, Ni-Cu heterostructures (HSs) were synthesized by spark plasma sintering (SPS), rolling deformation, subsequent heat treatment. density of the Ni/Cu interface HS materials can be independently tuned, thus effect hetero-deformation-induced (HDI) strengthening in tuned. is tu...

Abstract The policy capacity framework offers relevant analytical ideas that can be mobilized for health system strengthening. However, the employment of this in field constitutes a interdisciplinary gap knowledge. This themed issue explores relationships between and strengthening, multidimensional way, high-income low–middle-income countries. introduction unpacks dynamic interrelationships bri...

Temperature field inversion of heat-source systems (TFI-HSS) with limited observations is essential to monitor the system health. Although some methods such as interpolation have been proposed solve TFI-HSS, those existing ignore correlations between data constraints and physics constraints, causing low precision. In this work, we develop a physics-informed neural network-based temperature (PIN...

In this paper, we investigate the numerical error propagation and provide systematic backward stability analysis for some hierarchical rank structured matrix algorithms. We prove the backward stability of various important hierarchically semiseparable (HSS) methods, such as HSS matrix-vector multiplications, HSS ULV linear system solutions, HSS linear least squares solutions, HSS inversions, an...