Functional programming and symbolic computation provide software for explicit calculations in algebraic topology. We present here one such application to the design of algorithms for computations in the homology of a central extension of groups.

This paper presents an on-line obstacle avoidance scheme for robot arms. This method is directly formulated in the Cartesian space and uses complete information about the workspace. The strategy is to detect the collision and to plan the motion of each link successively, starting from the base...

This paper describes a new approach to find the shape of a piece of bent fabric. A general form for the potential and bending energy stored in a fabric is stated, based on the frictional couple theory. With the help of the calculus of variations the differential equation for the bent shape is...

We give a survey of how computer algebra can be used to help the mathematician to guess results and to prove theorems in homological algebra. Our main point is that the Poincaré-Betti series of a commutative graded algebra contains much deeper information and is harder to calculate than the...

The computation of the radical of a zero-dimensional ideal plays an important role in various areas of computer algebra. A bunch of different methods have been published to meet this task (see e.g. [4,8,11,13–17]). The method presented in this paper is strongly connected to a recent approach...

We describe a symbolic-numerical method for the Fourier stability analyses of difference initial-value problems approximating the initial-value problems for hyperbolic or parabolic PDEs. The Fourier method is reduced to the algebra of the resultants. We further use the REDUCE computer algebra...

In this work, the Evaluation transform is adapted to interpret the polylogarithms as being the Evaluation of the words yxn, for meromorphic kernels and meromorphic inputs. The functional equations on polylogarithms can be obtained, then, via combinatorics on words and the relations between the...

Speech synthesis by rule has made considerable advances and it is being used today in numerous text-to-speech synthesis systems. Current systems are able to synthesise pleasant-sounding voices at high intelligibility levels. However, because their synthetic speech quality is still inferior to...

The aim of this paper is to present Cabri-graph, a system intended for students and researchers using graph theoric concepts. The objective of Cabri-graph is to alow any user to perform on his computer the same manipulations or computations on a graph that he can do on a sheet of paper, as...

Fuzzy logic theory, introduced by Zadeh (1965), has been used in different approaches in control theory. Fuzzy inference using a data base of an expert knowledge is the most widely used. A second approach, first presented by Sugeno, consists in the use of several models representing a partial...