Automata model

Cellular automata make up a class of completely discrete dynamical systems, which have became a core subject in the sciences of complexity due to their conceptual simplicity, easiness of implementation for computer simulation, and their ability to exhibit a wide variety of amazingly complex behavior. The feature of simplicity behind complexity of cellular automata has attracted the researchers' attention from a wide range of divergent fields of study of science, which extend from the exact disciplines of mathematical physics up to the social ones, and beyond....
0p cucdai_1 20102012 26 9 Download

Modelling and simulation are disciplines of major importance for science and engineering. There is no science without models, and simulation has nowadays become a very useful tool, sometimes unavoidable, for development of both science and engineering. The main attractive feature of cellular automata is that, in spite of their conceptual simplicity which allows an easiness of implementation for computer simulation, as a detailed and complete mathematical analysis in principle, they are able to exhibit a wide variety of amazingly complex behaviour....
0p cucdai_1 20102012 31 5 Download

In this paper we introduce a novel use of the lexicographic semiring and motivate its use for speech and language processing tasks. We prove that the semiring allows for exact encoding of backoff models with epsilon transitions. This allows for offline optimization of exact models represented as large weighted ﬁnitestate transducers in contrast to implicit (online) failure transition representations.
5p hongdo_1 12042013 28 2 Download

In this paper I present a Master’s thesis proposal in syntaxbased Statistical Machine Translation. I propose to build discriminative SMT models using both treetostring and treetotree approaches. Translation and language models will be represented mainly through the use of Tree Automata and Tree Transducers. These formalisms have important representational properties that makes them wellsuited for syntax modeling. nce it’s u
5p hongdo_1 12042013 19 2 Download

Stateoftheart computerassisted translation engines are based on a statistical prediction engine, which interactively provides completions to what a human translator types. The integration of human speech into a computerassisted system is also a challenging area and is the aim of this paper. So far, only a few methods for integrating statistical machine translation (MT) models with automatic speech recognition (ASR) models have been studied. They were mainly based on N best rescoring approach. ...
8p hongvang_1 16042013 23 2 Download

This paper describes discriminative language modeling for a large vocabulary speech recognition task. We contrast two parameter estimation methods: the perceptron algorithm, and a method based on conditional random ﬁelds (CRFs). The models are encoded as deterministic weighted ﬁnite state automata, and are applied by intersecting the automata with wordlattices that are the output from a baseline recognizer. The perceptron algorithm has the beneﬁt of automatically selecting a relatively small feature set in just a couple of passes over the training data. ...
8p bunbo_1 17042013 14 2 Download

Both probabilistic contextfree grammars (PCFGs) and shiftreduce probabilistic pushdown automata (PPDAs) have been used for language modeling and maximum likelihood parsing. We investigate the precise relationship between these two formalisms, showing that, while they define the same classes of probabilistic languages, they appear to impose different inductive biases.
8p bunrieu_1 18042013 24 2 Download

M I T ArtificialIntelligenceLaboratory 545 Technology Square Cambridge, M A 02139, U S A ABSTRACT In this paper we apply some recent work of Angluin (1982) to the induction of the English auxiliary verb system. In general, the induction of finiteautomata is computationally intractable. However, Angluin shows that restricted finite automata, the Itreversible automata, can be learned by el~cient (polynomial time) algorithms.
6p bungio_1 03052013 16 2 Download

This paper presents an algorithm for the compilation of regular formalisms with rule features into finitestate automata. Rule features are incorporated into the right context of rules. This general notion can also be applied to other algorithms which compile regular rewrite rules into automata.
8p bunthai_1 06052013 15 2 Download

In this paper we describe an approach to constraint based syntactic theories in terms of finite tree automata. The solutions to constraints expressed in weak monadic second order (MSO) logic are represented by tree a u t o m a t a recognizing the assignments which make the formulas true. We show that this allows an efficient representation of knowledge about the content of constraints which can be used as a practical tool for grammatical theory verification. We achieve this by using the intertranslatability of formulae of MSO logic and tree a u t o m a t a...
8p bunthai_1 06052013 17 2 Download

In this project, traffic simulation according to the cellular automaton of the NagelSchreckenberg model (1992) with different boundary conditions. The sudden occurrence of traffic jams is successfully realised as well as boundary induced phases and phase transitions are observed in the Asymmetric Simple Exclusion Process. The extension to the Velocity Dependent Randomization model leads to metastabile high flow states and hysteresis of the flow. The impact of speed limits on the probability of the formation of traffic jams is investigated.
10p nguyenhaisu 07082015 10 2 Download

The modelling of traffic flow using methods and models from physics has a long history. In recent years especially cellular automata models have allowed for largescale simulations of large traffic networks faster than real time. On the other hand, these systems are interesting for physicists since they allow to observe genuine nonequilibrium effects. Here the current status of cellular automata models for traffic flow is reviewed with special emphasis on nonequilibrium effects (e.g. phase transitions) induced by on and offramps.
23p nguyenhaisu 07082015 17 2 Download

Road traffic microsimulations based on the individual motion of all the involved vehicles are now recognized as an important tool to describe, understand, and manage road traffic. Cellular automata (CA) are very efficient way to implement vehicle motion. CA is a methodology that uses a discrete space to represent the state of each element of a domain, and this state can be changed according to a transition rule.
7p nguyenhaisu 07082015 11 2 Download

In this paper, we extend the NagelSchreckenberg (NaSch) model by introducing disordered acceleration and deceleration terms. The disorder leads to segregated states where the flow is constant at intermediate densities for high values of breaking probability p. Within the model we present a density wave behavior appears below a critical value of p. Such result was found in car following models with an optimal velocity. The behavior of the gap distribution shows that the traffic exhibits a self organized criticality for high values of p and random deceleration.
5p nguyenhaisu 07082015 7 2 Download

We study a simple threelane cellular automaton, based upon the well known NagelSchreckenberg model, and examine the effect of slow cars in such a system. We point out the important parameters defining the shape of the fundamental digram for the threelane model and compare it to that of a twolane one, showing the new mode of interactions between lanes. It is possible to reduce the influence of slow cars by choosing an adequate version of the symmetry with respect to lanes.
11p nguyenhaisu 07082015 12 2 Download

This paper reviews the range of traffic models, with particular attention to microsimulation. Although there are major types, there are so many hybrids that it is difficult to classify them all. The standard way of assigning traffic to a network is to find a static equilibrium from which no driver would be able to find a quicker route. This gives fairly good predictions of the link flows resulting from driver choices.
11p nguyenhaisu 07082015 6 2 Download

Mời bạn đọc cùng tham khảo Cellular Automata (CA) in transportation sau đây. Tài liệu hữu ích cho kỹ sư cầu đường, những ai quan tâm đến vấn đề giao thông đường bộ.
2p nguyenhaisu 07082015 11 2 Download

Recent text and speech processing applications such as speech mining raise new and more general problems related to the construction of language models. We present and describe in detail several new and efﬁcient algorithms to address these more general problems and report experimental results demonstrating their usefulness.
8p bunbo_1 17042013 14 1 Download

Bernard Lang defines parsing as ~ calculation of the intersection of a FSA (the input) and a CFG. Viewing the input for parsing as a FSA rather than as a string combines well with some approaches in speech understanding systems, in which parsing takes a word lattice as input (rather than a word string). Furthermore, certain techniques for robust parsing can be modelled as finite state transducers. In this paper we investigate how we can generalize this approach for unification grammars. In particular we will concentrate on how we might the calculation of the intersection of a FSA and...
7p bunmoc_1 20042013 11 1 Download

We present a language model consisting of a collection of costed bidirectional finite state automata associated with the head words of phrases. The model is suitable for incremental application of lexical associations in a dynamic programming search for optimal dependency tree derivations. We also present a model and algorithm for machine translation involving optimal "tiling" of a dependency tree with entries of a costed bilingual lexicon. Experimental results are reported comparing methods for assigning cost functions to these models.
10p bunmoc_1 20042013 17 1 Download