Search results for "Computer architecture"
showing 10 items of 191 documents
Optimized FPGA-implementation of quadrature DDS
2003
This paper presents the optimized implementation of high performance quadrature direct digital synthesizers (DDS). Although VLSI designs and optimizations have already been discussed in the literature they may not be successfully translated into an FPGA-based technology. This work examines each phase-to-amplitude mapping technique, such as ROM compression and partitioning techniques and the CORDIC algorithm, and it proposes the most suitable structure for Virtex FPGAs in order to obtain the most efficient implementation in terms of area and throughput.
The effects of interletter spacing in visual-word recognition.
2010
Despite the importance of determining the effects of interletter spacing on visual-word recognition, this issue has often been neglected in the literature. The goal of the present study is to shed some light on this topic. The rationale is that a thin increase in interletter spacing, as in casino, may reduce lateral interference among internal letters without destroying a word's integrity and/or allow a more precise encoding of a word's letter positions. Here we examined whether identification times for word stimuli in a lexical decision task were faster when the target word had a slightly wider than default interletter spacing value relative to the default settings (e.g., casino vs. casino…
Improving Classification of Tweets Using Linguistic Information from a Large External Corpus
2016
The bag of words representation of documents is often unsatisfactory as it ignores relationships between important terms that do not co-occur literally. Improvements might be achieved by expanding the vocabulary with other relevant word, like synonyms.
Part-of-Speech Induction by Singular Value Decomposition and Hierarchical Clustering
2006
Part-of-speech induction involves the automatic discovery of word classes and the assignment of each word of a vocabulary to one or several of these classes. The approach proposed here is based on the analysis of word distributions in a large collection of German newspaper texts. Its main advantage over other attempts is that it combines the hierarchical clustering of context vectors with a previous step of dimensionality reduction that minimizes the effects of sampling errors.
A practical solution to the problem of automatic part-of-speech induction from text
2005
The problem of part-of-speech induction from text involves two aspects: Firstly, a set of word classes is to be derived automatically. Secondly, each word of a vocabulary is to be assigned to one or several of these word classes. In this paper we present a method that solves both problems with good accuracy. Our approach adopts a mixture of statistical methods that have been successfully applied in word sense induction. Its main advantage over previous attempts is that it reduces the syntactic space to only the most important dimensions, thereby almost eliminating the otherwise omnipresent problem of data sparseness.
An Extension of the VSM Documents Representation using Word Embedding
2017
Abstract In this paper, we will present experiments that try to integrate the power of Word Embedding representation in real problems for documents classification. Word Embedding is a new tendency used in the natural language processing domain that tries to represent each word from the document in a vector format. This representation embeds the semantically context in that the word occurs more frequently. We include this new representation in a classical VSM document representation and evaluate it using a learning algorithm based on the Support Vector Machine. This new added information makes the classification to be more difficult because it increases the learning time and the memory neede…
A simple algorithm for finding short sigma-definite representatives
2010
We describe a new algorithm which for each braid returns a quasi-geodesic sigma-definite word representative, defined as a braid word in which the generator sigma_i with maximal index i appears either only positively or only negatively.
On the suffix automaton with mismatches
2007
International audience; In this paper we focus on the construction of the minimal deterministic finite automaton S_k that recognizes the set of suffixes of a word w up to k errors. We present an algorithm that makes use of S_k in order to accept in an efficient way the language of all suffixes of w up to k errors in every window of size r, where r is the value of the repetition index of w. Moreover, we give some experimental results on some well-known words, like prefixes of Fibonacci and Thue-Morse words, and we make a conjecture on the size of the suffix automaton with mismatches.
Co-simulation platform based on systemc for multiprocessor system on chip architecture exploration
2007
Currently multiprocessor embedded systems are the principal vectors of semiconductor industry. Modelling, validating and analyzing a system performances impose the evolution of the traditional simulation techniques. In this paper we define the methodology we used in constructing the STARSoC co-simulation environment. This platform aims to explore at higher levels of abstractions a multiprocessors system on chip architectures. The platform reference design contains several OpenRISC 1200 Instruction Set Simulators (ISSs) wrapped under SystemC, and some basic peripherals within the SystemC simulation framework. Our purpose is to develop a complete design space exploration tool. In order to ass…
Design Space Exploration for a Custom VLIW Architecture: Direct Photo Printer Hardware Setting Using VEX Compiler
2008
Increasingly more computing power is demanded for contemporary applications such as multimedia, 3D visualization, and telecommunication. This paper presents a design space exploration (DSE) experience for an embedded VLIW processor that allows finding out the best architecture for given application. The proposed method has been implemented and tested using an image processing chain for direct photo printer. Our results show a considerable improvement in hardware cost and performance. After the best architecture is identified, we applied a technique to optimize the code in VEX system that uses ?inlining? function in order to reduce execution time.