Hardware Inexact Grammar Parser

In this paper, a platform is presented, that given a Stochastic Context-Free Grammar (SCFG), automatically outputs the description of a parser in synthesizable Hardware Description Language (HDL) which can be downloaded in an FPGA (Field Programmable Gate Arrays) board. Although the proposed methodology can be used for various inexact models, the probabilistic model is analyzed in detail and the extension to other inexact schemes is described. Context-Free Grammars (CFG) are augmented with attributes which represent the probability values. Initially, a methodology is proposed based on the fact that the probabilities can be evaluated concurrently with the parsing during the parse table construction by extending the fundamental parsing operation proposed by Chiang & Fu. Using this extended operation, an efficient architecture is presented based on Earley’s parallel algorithm, which given an input string, generates the parse table while evaluating concurrently the probabilities of the generated dotted grammar rules in the table. Based on this architecture, a platform has been implemented that automatically generates the hardware design of the parser given a SCFG. The platform is suitable for embedded systems applications where a natural language interface is required or in pattern recognition tasks. The proposed hardware platform has been tested for various SCFGs and was compared with previously presented hardware parser for SCFGs based on Earley’s parallel algorithm. The hardware generated by the proposed platform is much less complicated than the one of comparison and succeeds a speed-up of one order of magnitude.

Parsing Bangla Grammar Using Context Free Grammar

Parsing plays a very prominent role in computational linguistics. Parsing a Bangla sentence is a primary need in Bangla language processing. This chapter describes the Context Free Grammar (CFG) for parsing Bangla language, and hence, a Bangla parser is proposed based on the Bangla grammar. This approach is very simple to apply in Bangla sentences, and the method is well accepted for parsing grammar. This chapter introduces a parser for Bangla language, which is, by nature, a predictive parser, and the parse table is constructed for recognizing Bangla grammar. Parse table is an important tool to recognize syntactical mistakes of Bangla sentences when there is no entry for a terminal in the parse table. If a natural language can be successfully parsed then grammar checking of this language becomes possible. The parsing scheme in this chapter works based on a top-down parsing method. CFG suffers from a major problem called left recursion. The technique of left factoring is applied to avoid the problem.

Parsing Bangla Grammar Using Context Free Grammar

Parsing plays a very prominent role in computational linguistics. Parsing a Bangla sentence is a primary need in Bangla language processing. This chapter describes the Context Free Grammar (CFG) for parsing Bangla language, and hence, a Bangla parser is proposed based on the Bangla grammar. This approach is very simple to apply in Bangla sentences, and the method is well accepted for parsing grammar. This chapter introduces a parser for Bangla language, which is, by nature, a predictive parser, and the parse table is constructed for recognizing Bangla grammar. Parse table is an important tool to recognize syntactical mistakes of Bangla sentences when there is no entry for a terminal in the parse table. If a natural language can be successfully parsed then grammar checking of this language becomes possible. The parsing scheme in this chapter works based on a top-down parsing method. CFG suffers from a major problem called left recursion. The technique of left factoring is applied to avoid the problem.