46113649
Analytical Decoupling, Decision of Compatibility and Partial Integration of Systems of Non-Linear Ordinary and Partial Differential Equations
895386
Size Reduction and Partial Decoupling of Systems of Equations
A method is presented that reduces the number of terms of systems of linear equations (algebraic, ordinary and partial differential equations). As a byproduct these systems have a tendency to become partially decoupled and are more likely to be factorizable or integrable. A variation of this method is applicable to nonlinear systems. Modifications to improve efficiency are given and examples are shown. This procedure can be used in connection with the computation of the radical of a differential ideal (differential Grobner basis).
5578706
Checking Life-and Death Problems in Go
1703030
Optimizing GoTools' Search Heuristics using Genetic Algorithms
GoTools is a program which solves life & death problems in the game of Go. This paper describes experiments using a Genetic Algorithm to optimize heuristic weights used by GoTools' tree-search. The complete set of heuristic weights is composed of different subgroups, each of which can be optimized with a suitable fitness function. As a useful side product, an MPI interface for FreePascal was implemented to allow the use of a parallelized fitness function running on a Beowulf cluster. The aim of this exercise is to optimize the current version of GoTools, and to make tools available in preparation of an extension of GoTools for solving open boundary life & death problems, which will introduce more heuristic parameters to be fine tuned.
19107527
Investigating DEs with CRACK and related programs
The aim of the package to be described is to try modularizing the investigation of differential equations for which there are no complete algorithms available yet. All, that is available for such problems are algorithms for special situations, e.g. when first integrals with a simple structure exist (e.g. polynomial in first derivatives) or when the problem has infinitesimal symmetries. In all such cases, finally a system of differential equations has to be solved which is overdetermined in the sense that more conditions have to be satisfied than there are unknown functions. To do a variety of such investigations efficiently, like a symmetry analysis, application of symmetries, determination of first integrals, differential factors, equivalent Lagrangians, the strategy is to have one package (CRACK) for simplifying DEs and solving simple DEs as effective as possible and to use this program as the main tool for all the above mentioned investigations. For each investigation there is then only a short program necessary to just formulate the necessary conditions in form of an overdetermined DE-system and to call CRACK to solve this, possibly in a number of successive calls. The examples below shall indicate the range of possible applications.
27429660
Automatic determination of dynamical symmetries of ordinary differential equations
We describe the application of a computer program CRACKSTAR for the exact analytic solution of overdetermined systems of differential equations which result in determining point-, contact- and dynamical symmetries of ordinary differential equations. Examples are discussed.ZusammenfassungWir beschreiben die Anwendung des Computerprogramms CRACKSTAR zur exakten Lösung überbestimmter Differentialgleichungssysteme, die von der Bestimmung von Punkt- und Berührungssymmetrien sowie dynamischer Symmetrien gewöhnlicher Differentialgleichungen herrühren.
23941957
Model Checking
Die Gewährleistung der korrekten
Funktionsweise von Hard- und Software ist ein entscheidender
Faktor bei der heutigen Systementwicklung. Dies trifft ganz
besonders auf das Gebiet der sog. „sicherheitskritischen“
Systeme zu, bei dem ein Systemversagen Menschenleben gefährden
kann.
11330765
Transparent filtering of streams in GLADE
Note: Also available as Technical Report EPFL 97/241 Reference LGL-CONF-1997-009 Record created on 2005-09-20, modified on 2016-08-08
15117189
Global Biclustering of Microarray Data
We consider the problem of simultaneously clustering genes and conditions of a gene expression data matrix. A bicluster is defined as a subset of genes that show similar behavior within a subset of conditions. Finding biclusters can be useful for revealing groups of genes involved in the same molecular process as well as groups of conditions where this process takes place. Previous work either deals with local, bicluster-based criteria or assumes a very specific structure of the data matrix (e.g. checkerboard or block-diagonal) (Ryan et al., 2005). In contrast, our goal is to find a set of flexibly arranged biclusters which is optimal in regard to a global objective function. As this is a NP-hard combinatorial problem, we describe several techniques to obtain approximate solutions. We benchmarked our approach successfully on the Alizadeh B-cell lymphoma data set (Alizadeh et al., 2000)
30440565
Ein optisches Meßsystem zur Echtzeitanalyse von Konturen mit der PLL-Schaltung
Mit einer einfachen analogen Phasenmestechnik, der PLL-Schaltung, lassen sich Phasenmessungen mit hoher Genauigkeit in Echtzeit realisieren. Insbesondere in optischen Messystemen, in denen mit einer Phasenbestimmung aus einem harmonischen Intensitatsmuster die gesuchte physikalische Mesgrose extrahiert werden mus, stellt die hier vorgestellte Methode eine lohnende Alternative zu den bekannten digitalen Auswertemethoden dar. Dabei entfallen sowohl die Beschrankung auf statische Phasenbilder sowie Problematiken bei der Phasenentfaltung. Die Konturmessung an einem Kalibrierkor per sowie ein Versuch zur Bestimmung des Kriechverhaltens eines PE-Schaumes werden als Beispielmessungen vorgestellt.
1643372
Fault Tolerance by Transparent Replication for Distributed Ada 95
This paper presents the foundations of RAPIDS ("Replicated Ada Partitions In Distributed Systems"), an implementation of the Distributed Systems Annex E incorporating the transparent replication of partitions in distributed Ada 95 applications. RAPIDS is a replication manager for semi-active replication based on a piecewise deterministic computation model. It guarantees replica consistency for arbitrary Ada 95 partitions despite the inherent non-determinism of multitasking, offering k-resilient partitions. The RAPIDS prototype is implemented for the GNAT compiler and evolved from its PCS, Garlic.