A Generative System for Mamluk Madrasa Form-Making

In this paper, a parametric shape grammar for the derivation of the floor plans of educational buildings (madrasas) in Mamluk architecture is presented. The grammar is constructed using a corpus of sixteen Mamluk madrasas that were built in Egypt, Syria, and Palestine during the Mamluk period. Based on an epistemological premise of structuralism, the morphology of Mamluk madrasas is analyzed to deduce commonalities of the formal and compositional aspects among them. The set of underlying common lexical and syntactic elements that are shared by the study cases is listed. The shape rule schemata to derive Mamluk madrasa floor plans are formulated. The sets of lexical elements and syntactic rules are systematized to form a linguistic framework. The theoretical framework for the formal language of Mamluk architecture is structured to establish a basis for a computerized model for the automatic derivation of Mamluk madrasa floor plans.     

Distributed Event Graphs: Formalizing Component-based Modelling and Simulation

In this work an extension to the classical Event Graphs formalism for discrete-event simulation is presented. The extensions are oriented towards the specification of component-based models. The abstract syntax has been defined through meta-modelling. Several methodological issues are discussed, concerning the use of two different meta-modelling levels or collapsing the language into a single one, where “instance-of” relationships are used between processes and their classes. The operational semantics have been defined through graph transformation. This formal definition enables analysis before code is generated from the model. The syntax and semantics of the visual language have been implemented in the multi-paradigm tool AToM³, together with a code generator that produces stand-alone applications able to run the analysed models in real-time.     

Learning Syntax by Automata Induction

In this paper we propose an explicit computer model for learning natural language syntax based on Angluin's (1982) efficient induction algorithms, using a complete corpus of grammatical example sentences. We use these results to show how inductive inference methods may be applied to learn substantial, coherent subparts of at least one natural language — English — that are not susceptible to the kinds of learning envisioned in linguistic theory. As two concrete case studies, we show how to learn English auxiliary verb sequences (such as could be taking, will have been taking) and the sequences of articles and adjectives that appear before noun phrases (such as the very old big deer). Both systems can be acquired in a computationally feasible amount of time using either positive examples, or, in an incremental mode, with implicit negative examples (examples outside a finite corpus are considered to be negative examples). As far as we know, this is the first computer procedure that learns a full-scale range of noun subclasses and noun phrase structure. The generalizations and the time required for acquisition match our knowledge of child language acquisition for these two cases. More importantly, these results show that just where linguistic theories admit to highly irregular subportions, we can apply efficient automata-theoretic learning algorithms. Since the algorithm works only for fragments of language syntax, we do not believe that it suffices for all of language acquisition. Rather, we would claim that language acquisition is nonuniform and susceptible to a variety of acquisition strategies; this algorithm may be one these.     

View Transformation in Visual Environments applied to Algebraic High-Level Nets

Graph transformation systems are a well-founded and adequate technique to describe the syntax of visual modeling languages and to formalize their semantics. Moreover, graph transformation tools support visual model specification, simulation and analysis on the basis of the rich underlying theory.Despite the benefits of model validation by simulation, sometimes it is preferable for users to see the model's behavior not in the abstract layout of the formal model, but as scenarios presented in the layout of the specific application domain. Hence, we propose the integration of a domain-oriented animation view with the model transformation system. An animation view allows to define scenario animations in a systematic way based on the formal model. The specification of the well-known Dining Philosophers system as algebraic high-level Petri net serves as running example for the extension of the model by an animation view and the derivation of animation rules from the model transformation system. A scenario animation then is obtained as transformation by applying the animation rules to model states. This visualizes the behavior of the model in the layout of philosophers sitting around a table and eating with chopsticks. A prototypical implementation of the concepts in GenGED, a visual language environment, is presented.     

基于FUG的藏语句法形式化描述

针对藏语自然语言形式化的实际需求,分析了用复杂特征描述藏语句子的必要性,引入了复杂特征集和合一运算的概念。以形式化为出发点,以现代语言学理论为后盾,以实例举证的方式对藏语词汇、句法、语义的规则及句子合一运算提出了探索性的研究思路,并且采用框式表示的方法,力求从形式化的角度为藏语自然语言处理提供便利。     

Some formal properties of stratified feature grammars

In this paper, we investigate the formal expressive properties of Stratified Feature Grammar (SFG), a new logic-based linguistic framework motivated by relational grammar and metagraph grammar, as well as by Kasper-Rounds logic. The driving force behind SFG is the generalization of the conceptfeature from an unanalyzable atomic one to a sequence of so-called R-signs. The linguistic interpretation of thesestratified features is that each R-sign in such a sequence denotes a primitive grammatical relation such as subject or direct object in different syntactic “strata”. This generalization permits the specification of a rigorous feature-structure-based formalism for natural-language grammars based on the view that syntax is “multistratal” and “relational”. The introduction of stratified features leads to several other innovations, two of which might have utility in other frameworks. One is the idea of imposing a partial order on features. The other is the concept of(data) justification: essentially, this is a stipulation that for an S-graph to be well-formed with respect to some grammarG it must, in addition to satisfying the rules ofG, have each of its “core” data (each feature occurrence, each node-label occurrence and each instance of so-called structure-sharing) justified in a formally precise manner by some rule of Justification ensures that. Justification ensures that satisfying S-graphs do not have more structure than absolutely necessary and so makes it appealing to a notion of “minimal model” otiose. Justification plays a key role in a number of our proofs. The formal results presented here include the following. First, it is proved that in the unrestricted SFG framework, every type 0 (r.e.) language is generated by some SFG. Then, we restrict the framework to so-calledbounded SFG with two linguistically motivated principles: Lexical Anchoring and Boundedness. Anchoring requires, in essence, that each core datum of an S-graph be justified by aword in its yield. Boundedness insures that S-graph features are short. Although these restrictions together put the class of bounded SFG languages well within the class of recursive languages, we go on to demonstrate that the recognition problem for bounded SFG is NP-hard. Further, we establish that a bounded SFG language need not be semi-linear. On the matter of upper bounds, we show that every bounded SFL can be recognized by a nondeterministic Turing machine inn logn space and polynomial time and that the recognition problem for bounded SFL's is NP-complete.     

The context-splittable normal form for Church–Rosser language systems

In this paper the context-splittable normal form for rewriting systems defining Church–Rosser languages is introduced. Context-splittable rewriting rules look like rules of context-sensitive grammars with swapped sides. To be more precise, they have the form uvw→uxw with u,v,w being words, v being nonempty and x being a single letter or the empty word. It is proved that this normal form can be achieved for each Church–Rosser language and that the construction is effective. Some interesting consequences of this characterization are given, too.     

Fresh O'Caml: Nominal Abstract Syntax for the Masses

Nominal abstract syntax, as pioneered by the 'FreshML' series of metalanguages, provides first-order tools for the representation and manipulation of syntax involving bound names, binding operations and α-equivalence. Fresh O'Caml fuses nominal abstract syntax with the full Objective Caml language to yield a functional programming language with powerful facilities for representing and manipulating syntax. In this paper, we first provide an examples-driven overview of the language and its functionality. Then we proceed to comment on some of the difficult issues involved in implementing nominal abstract syntax and explain how they have been addressed in the latest version of the compiler.     

Nominal logic, a first order theory of names and binding

This paper formalises within first-order logic some common practices in computer science to do with representing and reasoning about syntactical structures involving lexically scoped binding constructs. It introduces Nominal Logic, a version of first-order many-sorted logic with equality containing primitives for renaming via name-swapping, for freshness of names, and for name-binding. Its axioms express properties of these constructs satisfied by the FM-sets model of syntax involving binding, which was recently introduced by the author and M.J. Gabbay and makes use of the Fraenkel–Mostowski permutation model of set theory. Nominal Logic serves as a vehicle for making two general points. First, name-swapping has much nicer logical properties than more general, non-bijective forms of renaming while at the same time providing a sufficient foundation for a theory of structural induction/recursion for syntax modulo α-equivalence. Secondly, it is useful for the practice of operational semantics to make explicit the equivariance property of assertions about syntax – namely that their validity is invariant under name-swapping.     

Control space of natural-language syntactic structures

A formal model of the structure of natural-language sentences is considered, based on the concept of control space. The proposed model allows for recursion of predicative and attributive relations in the language and generalizes the linguistic models of domination trees and constituent systems. It is designed for efficient implementation in parallel computing systems.Translated from Kibernetika, No. 3, pp. 11–17, May–June 1990.