Results 41 to 50 of about 429,306 (281)
Explicit solutions to correlation matrix completion problems, with an application to risk management and insurance [PDF]
Royal Society Open Science, 2018 We derive explicit solutions to the problem of completing a partially specified correlation matrix. Our results apply to several block structures for the unspecified entries that arise in insurance and risk management, where an insurance company with ...
Dan I. Georgescu +2 more
doaj +1 more source
Strictly Hermitian Positive Definite Functions
, 2004 Let H be any complex inner product space with inner product . We say that f : C -->C is Hermitian positive definite on H if the matrix $$(f())_{r,s=1}^n \eqno(*)$$ is Hermitian positive definite for all choice of z^1,...,z^n in H, all n.
Pinkus, Allan
core +4 more sources
The maximal operator of a normal Ornstein--Uhlenbeck semigroup is of weak type (1,1) [PDF]
, 2019 Consider a normal Ornstein\u2013Uhlenbeck semigroup in R^n, whose co- variance is given by a positive definite matrix. The drift matrix is assumed to have eigenvalues only in the left half-plane.
Casarino, Valentina +2 more
core +3 more sources
Predicting Atomic Charges in MOFs by Topological Charge Equilibration
Advanced Functional Materials, EarlyView.An atomic charge prediction method is presented that is able to accurately reproduce ab‐initio‐derived reference charges for a large number of metal–organic frameworks. Based on a topological charge equilibration scheme, static charges that fulfill overall neutrality are quickly generated.
Babak Farhadi Jahromi +2 more
wiley +1 more source
Multivariate transient price impact and matrix-valued positive definite functions
, 2015 We consider a model for linear transient price impact for multiple assets that takes cross-asset impact into account. Our main goal is to single out properties that need to be imposed on the decay kernel so that the model admits well-behaved optimal ...
Alfonsi, Aurélien +2 more
core +3 more sources
Laser‐Assisted Processing and Modification of Bioactive Glasses: A Review
Advanced Healthcare Materials, EarlyView.Laser technologies provide powerful tools to process and transform bioactive glasses for advanced biomedical applications. This review discusses laser‐matter interaction mechanisms, laser surface engineering, and laser‐assisted fabrication of scaffolds and nanofibers.
Antonio Riveiro +8 more
wiley +1 more source
Advanced Materials, EarlyView.AI‐Assisted Workflow for (Scanning) Transmission Electron Microscopy: From Data Analysis Automation to Materials Knowledge Unveiling. Abstract (Scanning) transmission electron microscopy ((S)TEM) has significantly advanced materials science but faces challenges in correlating precise atomic structure information with the functional properties of ...
Marc Botifoll +19 more
wiley +1 more source
Positive definite solutions of some matrix equations
Linear Algebra and its Applications, 2008 The authors investigate some existence questions of positive semi-definite solutions for certain classes of matrix equations known as the generalized Lyapunov equations. The authors use a simple but useful lemma (Lemma 2.1) and properties of Fourier transforms to get sufficient and necessary conditions for certain equations and only sufficient for ...
Cvetković, Aleksandar S. +1 more
openaire +2 more sources
Rank-preserving geometric means of positive semi-definite matrices
, 2012 The generalization of the geometric mean of positive scalars to positive definite matrices has attracted considerable attention since the seminal work of Ando.
Bonnabel, Silvere +2 more
core +1 more source
Advanced Robotics Research, EarlyView.A codesign multiobjective optimization framework was developed to enhance the morphology and controller of a snake‐like robot driven by artificial muscles. It improved planar locomotion, agility, and power efficiency. The approach optimized link geometry and controller gains, revealing that shorter muscles near joints and longer linkages maximize ...
Ayla Valles, Mahdi Haghshenas‐Jaryani
wiley +1 more source