Spa, Belgium, June 8-13, 2014.

This symposium is the nineteenth in a series, previously called the Gatlinburg Symposia, and will be hosted by the Universite catholique de Louvain and the Katholieke Universiteit Leuven.

The Symposium is very informal, with the intermingling of young and established researchers a priority. Participants are expected to attend the entire meeting. The fifteenth Householder Award for the best thesis in numerical linear algebra since 1 January 2011 will be presented.

Attendance at the meeting is by invitation only. Applications will be solicited from researchers in numerical linear algebra, matrix theory, and related areas such as optimization, differential equations, signal processing, and control. Each attendee will be given the opportunity to present a talk or a poster. Some talks will be plenary lectures, while others will be shorter presentations arranged in parallel
sessions.

The application deadline will be some time in Fall 2013. It is expected that partial support will be available for some students, early career participants, and participants from countries with limited resources.

The Householder Symposium takes place in cooperation with the Society for Industrial and Applied Mathematics (SIAM) and the SIAM Activity Group on Linear Algebra.

The deadline for the conference application is October 31, 2013.
Notification of acceptance: 31 January 2014


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Updating BIF preconditioners

Professor Jose Mas

Instituto de Matemática Multidisciplinar, Universitat Politècnica de València

August 6th (Tuesday) 11:00-12:00am
National Institute of Informatics, 12th floor, Lecture room 1 (Room 1212)

Let $Ax=b$ be a large and sparse system of linear equations where $A$ is a general nonsingular matrix. An approximate
solution is frequently obtained by applying preconditioned iterations.
Consider the matrix $B=A+PQ^T$ where $P, Q \in \mathbb{R}^{n \times k}$ with $k <<n$ are full rank matrices.
Some techniques to update a previously computed preconditioner for $A$, such that the update can be used to solve
the updated linear system $Bx=b$ by preconditioned iterations will be analyzed,
in particular if the original preconditioner is computed using the BIF preconditioner.
Conditions on the matrices $P$ and $Q$ that guarantee the
invertibility of the matrix $B$ will be presented as well as the results of some numerical experiments with different types of problems.