8) Solution of Saddle Bents

Numerical solution of saddle point problems

Large linear systems of saddle point type arise in a wide variety of applications throughout computational science and engineering. Due to their indefiniteness and often poor spectral properties, such linear systems represent a significant challenge for solver developers. In recent years there has been a surge of interest in saddle point problems, and numerous solution techniques have been prop...

Pushover Analysis of Long Span Bridge Bents

Acquired Clustering Properties and Solution of Certain Saddle Point Systems

Many mathematical models involve flow equations characterized by nonconstant viscosity, and a Stokes-type problem with variable viscosity coefficient arises. Appropriate block diagonal preconditioners for the resulting algebraic saddle point linear system produce well-clustered spectra, except for a few interior isolated eigenvalues which may tend to approach zero. These outliers affect the con...

An Ordering Method for the Direct Solution of Saddle-point

An ordering method and accompanying factorization for the direct solution of saddlepoint matrices is presented. A simple constraint on ordering together with an assumption on the rank of parts of the matrix are sufficient to guarantee the existence of the LDLT factorization, stability concerns aside. In fact, D may be taken to be a diagonal matrix with ±1 along the diagonal, and be fully determ...

Solution to spectroscopy challenge 8.

Malic acid was first isolated by Carl Wilhelm Scheele from apple juice in 1785. Scheele was born in 1742 in Stralsund. The German seaport of Stralsund is situated on the southern coast of a sound of the Baltic Sea that separates the island of Rügen from the mainland. This small town remained under Swedish control until 1815, when it became a part of the Prussian Province of Pomerania. Thus, Sch...