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Derivation of BiCG from the conditions defining Lanczos' method for solving a system of linear equations

Petr Tichý, Jan Zítko (1998)

Applications of Mathematics

Lanczos’ method for solving the system of linear algebraic equations A x = b consists in constructing a sequence of vectors x k in such a way that r k = b - A x k r 0 + A 𝒦 k ( A , r 0 ) and r k 𝒦 k ( A T , r ˜ 0 ) . This sequence of vectors can be computed by the BiCG (BiOMin) algorithm. In this paper is shown how to obtain the recurrences of BiCG (BiOMin) directly from this conditions.

Derivation of physically motivated constraints for efficient interval simulations applied to the analysis of uncertain dynamical systems

Mareile Freihold, Eberhard P. Hofer (2009)

International Journal of Applied Mathematics and Computer Science

Interval arithmetic techniques such as VALENCIA-IVP allow calculating guaranteed enclosures of all reachable states of continuous-time dynamical systems with bounded uncertainties of both initial conditions and system parameters. Considering the fact that, in naive implementations of interval algorithms, overestimation might lead to unnecessarily conservative results, suitable consistency tests are essential to obtain the tightest possible enclosures. In this contribution, a general framework for...

Description of the multi-dimensional finite volume solver EULER

Pavel Šolín, Karel Segeth (2002)

Applications of Mathematics

This paper is aimed at the description of the multi-dimensional finite volume solver EULER, which has been developed for the numerical solution of the compressible Euler equations during several last years. The present overview of numerical schemes and the explanation of numerical techniques and tricks which have been used for EULER could be of certain interest not only for registered users but also for numerical mathematicians who have decided to implement a finite volume solver themselves. This...

Detection and accommodation of second order distributed parameter systems with abrupt changes in input term: stability and adaptation

Michael A. Demetriou, Marios M. Polycarpou (1998)

Kybernetika

In this note, we employ nonlinear on-line parameter estimation methods based on adaptive neural network approximators for detecting changes due to actuator faults in a class of second order distributed parameter systems. The motivating example is a cantilevered beam actuated via a pair of piezoceramic patches. We examine changes in the control input term, which provide a simple and practical model of actuator failures. Using Lyapunov redesign methods, a stable learning scheme for fault diagnosis...

Detection codes in railway interlocking systems

Kárná, Lucie, Klapka, Štěpán (2013)

Applications of Mathematics 2013

This paper describes a model of influence of random errors on the safety of the communication. The role of the communication in railway safety is specified. To ensure a safe communication, using of safety code is important. The most important parameter of the safety code is the maximal value of the probability of undetected error. Problems related with computing of this value are outlined in the article. As a model for the information transmission the binary symmetrical channel is introduced. ...

Determinant evaluations for binary circulant matrices

Christos Kravvaritis (2014)

Special Matrices

Determinant formulas for special binary circulant matrices are derived and a new open problem regarding the possible determinant values of these specific circulant matrices is stated. The ideas used for the proofs can be utilized to obtain more determinant formulas for other binary circulant matrices, too. The superiority of the proposed approach over the standard method for calculating the determinant of a general circulant matrix is demonstrated.

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