Primitive Optimality Theory (OTP) (Eisner, 1997a; Albro, 1998), a computational model of Optimality Theory (Prince and Smolensky, 1993), employs a finite state machine to represent the set of active candidates at each stage of an Optimality Theoretic derivation, as well as weighted finite state machines to represent the constraints themselves. For some purposes, however, it would be convenient ...

Context-sensitive rewriting is a refined form of rewriting that explores a smaller reduction space by imposing some fixed restrictions on the replacements. Any Term Rewriting System (TRS) can be given a context-sensitive rewrite relation. In this paper, we review the theory of context-sensitive rewriting and formulate conditions to guarantee the confluence of this relation. Also, for left-linea...

Since the seminal work of Sampath et al. in 1996, despite the subsequent flourishing of techniques on diagnosis of discrete-event systems (DESs), the basic notions of fault and diagnosis have been remaining conceptually unchanged. Faults are defined at component level and diagnoses incorporate the occurrences of component faults within system evolutions: diagnosis is context-free. As this appro...

A major target of linguistics and cognitive science has been to understand what class of learning systems can acquire the key structures of natural language. Until recently, the computational requirements of language have been used to argue that learning is impossible without a highly constrained hypothesis space. Here, we describe a learning system that is maximally unconstrained, operating ov...

We develop a language model using probabilistic context-free grammars (PCFGs) that is \pseudo context-sensitive" in that the probability that a non-terminal N expands using a rule r depends on N's parent. We derive the equations for estimating the necessary probabilities using a variant of the inside-outside algorithm. We give experimental results showing that, beginning with a high-performance...

Standard grammar formalisms are defined without reflection of the incremental, serial and context-dependent nature of language processing; any incrementality must therefore be reflected by independently defined parsing and/or generation techniques, and context-dependence by separate pragmatic modules. This leads to a poor setup for modelling dialogue, with its rich speaker-hearer interaction an...

In this paper we develop a new description for subdivision surfaces based on a graph grammar formalism. Subdivision schemes are specified by a context sensitive grammar in which production rules represent topological and geometrical transformations to the surface’s control mesh. This methodology can be used for all known subdivision surface schemes. Moreover, it gives an effective representatio...

There is a long time open problem regarding the generative power of scattered context grammars without erasing rules. This problem tries to compare their generative power with context-sensitive grammars. In this paper, modified version of this problem will be presented. This modified version combines scattered context grammars with another model — grammar systems. It will be shown that when con...

We consider several types of similarity relationships between languages, and for an arbitrary language class we define appropriate similarity classes. We show that for any of the classes of regular, linear, contextfree, context-sensitive, recursive and recursively enumerable languages the appropriate similarity classes form an uncountable hierarchy of order type ω + λ + 2. We also show that the...

In this paper we present the concepts of drawn symbolic picture and symbolic picture. Such notions have been conceived as an extension of the concept of drawn pictures which was introduced by Maurer, Rozenberg and Welzl [31]. We provide a string description of such pictures. It consists of alternating words, i.e. strings whose letters are in alternation from an alphabet of symbols and an alphab...