An essential component of many applications in natural language processing is a language modeler able to correct errors in the text being processed. For optical character recognition (OCR), poor scanning quality or extraneous pixels in the image may cause one or more characters to be mis-recognized; while for spelling correction, two characters may be transposed, or a character may be inadverte...

This paper presents a comparative study of different redundant binary full adders (Plus-Plus-Minus (PPM) adder). These PPM adders are simulated to evaluate their performance in total power dissipation, speed and PDP. The performances of these circuits are based on 180nm process model at a supply voltage of 1.8V. We also proposed a new design for PPM adder using 13-transistors. The simulation re...

A prototype decoder for a serially concatenated pulse position modulation (SCPPM) code has been implemented in a field-programmable gate array (FPGA). At the time of this reporting, this is the first known hardware SCPPM decoder. The SCPPM coding scheme, conceived for free-space optical communications with both deep-space and terrestrial applications in mind, is an improvement of several dB ove...

Text mining involves the use of statistical and machine learning techniques to learn structural elements of text in order to search for useful information in previously unseen text. The need for these techniques have emerged out of the rapidly growing information era. Token identification is an important component of any text mining tool. The accomplishment of this task enhances the function of...

The “Prediction by Partial Matching” (PPM) data compression algorithm developed by Cleary and Witten is capable of very high compression rates, encoding English text in as little as 2.2 bits/character. Here it is shown that the estimates made by Cleary and Witten of the resources required to implement the scheme can be revised to allow for a tractable and useful implementation. In particular, a...

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The on-line sequence modelling algorithm `Prediction by Partial Matching' (PPM) has set the performance standard in lossless data compression research since Moffat's 1990 implementation, PPMC. Despite intense research activity, only Howard's 1993 escape-count update mechanism `D' has provided any consistent, order-independent performance improvement to PPMC (about 1%). Most notably, the recentl...