12,073 research outputs found
Dependency parsing resources for French: Converting acquired lexical functional grammar F-Structure annotations and parsing F-Structures directly
Recent years have seen considerable success in the generation of automatically obtained wide-coverage deep grammars for natural language processing, given reliable
and large CFG-like treebanks. For research within Lexical Functional Grammar framework, these deep grammars are
typically based on an extended PCFG parsing scheme from which dependencies are extracted. However, increasing success in statistical dependency parsing suggests that such deep grammar approaches to statistical parsing could be streamlined. We explore this novel approach to deep
grammar parsing within the framework of LFG in this paper, for French, showing that best results (an f-score of 69.46) for the established integrated architecture may be obtained for French
Ten virtues of structured graphs
This paper extends the invited talk by the first author about the virtues
of structured graphs. The motivation behind the talk and this paper relies on our
experience on the development of ADR, a formal approach for the design of styleconformant,
reconfigurable software systems. ADR is based on hierarchical graphs
with interfaces and it has been conceived in the attempt of reconciling software architectures
and process calculi by means of graphical methods. We have tried to
write an ADR agnostic paper where we raise some drawbacks of flat, unstructured
graphs for the design and analysis of software systems and we argue that hierarchical,
structured graphs can alleviate such drawbacks
Treebank-based acquisition of wide-coverage, probabilistic LFG resources: project overview, results and evaluation
This paper presents an overview of a project to acquire wide-coverage, probabilistic Lexical-Functional Grammar
(LFG) resources from treebanks. Our approach is based on an automatic annotation algorithm that annotates ārawā treebank trees with LFG f-structure information approximating to basic predicate-argument/dependency structure. From the f-structure-annotated treebank
we extract probabilistic unification grammar resources. We present the annotation algorithm, the extraction of
lexical information and the acquisition of wide-coverage and robust PCFG-based LFG approximations including
long-distance dependency resolution.
We show how the methodology can be applied to multilingual, treebank-based unification grammar acquisition. Finally
we show how simple (quasi-)logical forms can be derived automatically from the f-structures generated for the treebank trees
On the relevance of the neurobiological analogue of the finite-state architecture
We present two simple arguments for the potential relevance of a neurobiological analogue of the finite-state architecture. The first assumes the classical cognitive framework, is well-known, and is based on the assumption that the brain is finite with respect to its memory organization. The second is formulated within a general dynamical systems framework and is based on the assumption that the brain sustains some level of noise and/or does not utilize infinite precision processing. We briefly review the classical cognitive framework based on Church-Turing computability and non-classical approaches based on analog processing in dynamical systems. We conclude that the dynamical neurobiological analogue of the finite-state architecture appears to be relevant, at least at an implementational level, for cognitive brain systems
A compositional method for reliability analysis of workflows affected by multiple failure modes
We focus on reliability analysis for systems designed as workflow based compositions of components. Components are characterized by their failure profiles, which take into account possible multiple failure modes. A compositional calculus is provided to evaluate the failure profile of a composite system, given failure profiles of the components. The calculus is described as a syntax-driven procedure that synthesizes a workflows failure profile. The method is viewed as a design-time aid that can help software engineers reason about systems reliability in the early stage of development. A simple case study is presented to illustrate the proposed approach
A Modeling Approach based on UML/MARTE for GPU Architecture
Nowadays, the High Performance Computing is part of the context of embedded
systems. Graphics Processing Units (GPUs) are more and more used in
acceleration of the most part of algorithms and applications. Over the past
years, not many efforts have been done to describe abstractions of applications
in relation to their target architectures. Thus, when developers need to
associate applications and GPUs, for example, they find difficulty and prefer
using API for these architectures. This paper presents a metamodel extension
for MARTE profile and a model for GPU architectures. The main goal is to
specify the task and data allocation in the memory hierarchy of these
architectures. The results show that this approach will help to generate code
for GPUs based on model transformations using Model Driven Engineering (MDE).Comment: Symposium en Architectures nouvelles de machines (SympA'14) (2011
Monitoring distributed systems with distributed polyLarva
polyLarva is a language-agnostic runtime verification tool, which converts a polyLarvaScript into a monitor for a given system. While an implementation for polyLarva exists, the language and its compilation have not been formalised. We therefore present a formal implementation-independent model which describes the behaviour of polyLarvaScript, comprising of the uLarvaScript grammar and of a set of operational semantics. This allows us to prove important properties, such as determinism, and also enables us to reason about ways of re-designing the tool in a more scalable way. We also present a collection of denotational mappings for uLarvaScript converting the constructs of our grammar into constructs of a formal actor-based model, thus providing an Actor semantics for uLarvaScript. We are also able to prove certain correctness properties of the denotational translation such as that the denoted Actors behave in a way which corresponds to the behaviour described by our implementation-independent model. We finally present distPolyLarva, a prototype implementation of the distributed polyLarva tool, which implements the new actor-based semantics over a language that can natively handle distribution and concurrency called Erlang.peer-reviewe
Automatic annotation of the Penn-treebank with LFG f-structure information
Lexical-Functional Grammar f-structures are abstract syntactic representations approximating basic predicate-argument structure. Treebanks annotated with f-structure information are required as training resources for stochastic versions of unification and constraint-based
grammars and for the automatic extraction of such resources. In a number of papers (Frank, 2000; Sadler, van Genabith and Way, 2000) have developed methods for automatically annotating treebank resources with f-structure information. However, to date, these methods
have only been applied to treebank fragments of the order of a few hundred trees. In the present paper we present a new method that scales and has been applied to a complete treebank, in our case the WSJ section of Penn-II (Marcus et al, 1994), with more than 1,000,000 words in about 50,000 sentences
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