In the field of structural operational semantics (SOS), there have been several proposals both for syntactic rule formats guaranteeing the validity of algebraic laws, and for algorithms for automatically generating ground-complete axiomatizations. However, there has been no synergy between these two types of results. This paper takes the first steps in marrying these two areas of research in th...

We describe the implementation of an automated theorem pro-ver for algebraic speciications, in an algebraic speciication setting using the ASF+SDF Meta-environment. The current implementation is based on the implicit induction approach implemented in SPIKE 1, 2]. We consider the implementation as a case study on the tool generation within ASF+SDF which also provides an experimental basis for th...

cozero maps are generalized forms of cozero elements. two particular cases of cozero maps, slim and regular cozero maps, are significant. in this paper we present methods to construct slim and regular cozero maps from a given  cozero map. the construction of the slim and the regular cozero map from a cozero map are called slimming and regularization of the cozero map, respectively. also, we pro...

the operations in the set of fuzzy numbers are usually obtained bythe zadeh extension principle. but these definitions can have some disadvantagesfor the applications both by an algebraic point of view and by practicalaspects. in fact the zadeh multiplication is not distributive with respect tothe addition, the shape of fuzzy numbers is not preserved by multiplication,the indeterminateness of t...

This paper presents a new approach to fractal image generation by translating the evolution of graph grammar into graphics output. It uses the algebraic approach of graph grammar as a powerful abstract modeling tool for the generation of selfsimilar fractal images via its graph production, derivations and double-pushout construction. We focus on three proposed methods for image generation which...

We prove some finiteness theorems for the Picard functor of an algebraic stack, in the spirit of SGA6, exp. XII and XIII. In particular, we give a stacky version of Raynaud’s relative representability theorem, we give sufficient conditions for the existence of the torsion component of the Picard functor, and for the finite generation of the Néron-Severi groups or of the Picard group itself. We ...

The theory of combinatorial species, although invented as a purely mathematical formalism to unify much of combinatorics, can also serve as a powerful and expressive language for talking about algebraic data types. With potential applications to automatic test generation, generic programming, and language design, the theory deserves to be much better known in the functional programming communit...

We present a new algorithm to approximate real roots of multivariate polynomial systems. This algorithm combines the standard subdivision technique with a new domain reduction strategy. We introduce fat spheres as multidimensional quadratic enclosures for algebraic hypersurfaces. Then we present a local reformulation technique of the algebraic system, which provides a method to generate fat sph...