This paper describes a technique based on network grammars and abstraction to verify families of state transition systems The family of state transition systems is represented by a context free network grammar Using the structure of the network grammar our tech nique constructs an invariant which simulates all the state transition systems in the family A novel idea used in this paper is to use ...

Abstract Machine learning on trees has been mostly focused as input. Much less research investigated output, which many applications, such molecule optimization for drug discovery, or hint generation intelligent tutoring systems. In this work, we propose a novel autoencoder approach, called recursive tree grammar (RTG-AE), encodes via bottom-up parser and decodes grammar, both learned neural ne...

Minimalist grammars are a mildly context-sensitive grammar framework within which analyses in mainstream chomskyian syntax can be faithfully represented. Here it is shown that both the derivation tree languages and derived tree languages of minimalist grammars are closed under intersection with regular tree languages. This allows us to conclude that taking into account the possibility of ‘seman...

This paper describes a technique based on network grammars and abstraction to verify families of state-transition systems. The family of state-transition systems is represented by a context-free network grammar. Using the structure of the network grammar our technique constructs an invariant which simulates all the state-transition systems in the family. A novel idea used in this paper is to us...

A mathematical framework using formal language theory to describe and compare XML schema languages is presented. Our framework uses the work in two related areas { regular tree languages CDG + 97] and ambiguity in regular expressions BEGO71, BKW98]. Using these work as well as the content in two classical references HU79, AU79], we present the following results: (1) a normal form representation...

Finding optimum and near optimum edit scripts between an XML document and a schema is essential to correcting invalid XML documents. In this paper, we consider finding K optimum edit scripts between an XML document and a regular tree grammar. We first prove that the problem is NP-hard. We next show a pseudopolynomial-time algorithm for solving the problem.

We present a general framework to define an application–dependent weight measure on terms that subsumes e.g. total simplification orderings, and an O(n · log n) algorithm for the simultaneous computation of the minimal weight of a term in the language of each nonterminal of a regular tree grammar, based on Barzdins’ liquid–flow technique.

The Jordan center of a graph is defined as a vertex whose maximum distance to other nodes in the graph is minimal, and it finds applications in facility location and source detection problems. We study properties of the Jordan center in the case of random growing trees. In particular, we consider a regular tree graph on which an infection starts from a root node and then spreads along the edges...

This paper addresses the following general problem of tree regular model-checking: decide whether R * (L) ∩ L p = ∅ where R * is the reflexive and transitive closure of a successor relation induced by a term rewriting system R, and L and L p are both regular tree languages. We develop an automatic approximation-based technique to handle this – undecidable in general – problem in most practical ...

The third author noticed in his 1992 PhD Thesis [Sim92] that every regular tree language of infinite trees is in a class a(Dn(Σ2)) for some natural number n ≥ 1, where a is the game quantifier. We first give a detailed exposition of this result. Next, using an embedding of the Wadge hierarchy of non self-dual Borel subsets of the Cantor space 2 into the class ∆2, and the notions of Wadge degree...