Computer science

In the framework of the domain of Text Mining, and Document Classification in particular, an introduction into the field of Authorship Attribution is presented. Especially syntaxbased features and Machine Learning techniques suggest a new path in the identification of the author of a text which has not been subject to elaborate research yet. This paper reports experiments in Authorship Attribution in which the efficiency of syntax-based features is compared with that of lexical and token-level features. Memory Based Shallow Parsing (MBSP), scripts in the AWK programming language and the Rainbow program are applied for the extraction of style markers. Classification is performed by means of Machine Learning algorithms. The syntax-based features achieve an accuracy of 55% after testing on new data, while a combination of syntax-based, lexical and token-level features performs seven percent better. These results suggest that syntax-based features are good clues but not yet able to identify the author of a text independently. Nevertheless, we believe that extensive research on syntax-based features will lead to success.

In the recent years, there has been an explosive growth in the amount of visual data. Automatic Image Annotation (AIA) has been considered the state-of-the-art technique to annotate images with relevant keywords that enable efficient retrieval of these images. This paper discusses a simple multilabelling system that annotates a given image with certain relevant keywords. This technique uses bag of words model using SURF features for image representation. The annotation task uses a two-pass-KNN approach with modified ranking. The modified ranking takes into consideration the co-occurrence of the image labels. The system gives reasonable performance with Pascal VOC dataset, despite its simplicity. The relation between the predicted labels are obtained using a predefined ontology.

In the recent years, there has been an explosive growth in the amount of visual data. Automatic Image Annotation (AIA) has been considered the state-of-the-art technique to annotate images with relevant keywords that enable efficient retrieval of these images. This paper discusses a simple multilabelling system that annotates a given image with certain relevant keywords. This technique uses bag of words model using SURF features for image representation. The annotation task uses a two-pass-KNN approach with modified ranking. The modified ranking takes into consideration the co-occurrence of the image labels. The system gives reasonable performance with Pascal VOC dataset, despite its simplicity. The relation between the predicted labels are obtained using a predefined ontology.

A comprehensive characterization of the volumetric shrinkage of a commercially important aerospace resin (RTM6) during the various stages of the curing process was studied. The apparent volumetric shrinkage, evaluated from density measurements at room temperature, was correlated with the progress of epoxide conversion. During the entire curing process, the apparent volume shrinkage was found to be less than 3% and occurred before vitrification. A slight re-expansion of the resin, attributed to self-antiplasticization effects, was observed during postcuring at 1808C. It was concluded that residual stresses were not generated due to chemical cross-linking during curing but rather from thermal contraction occurring during the cooling stage after cure. A photo-elastic method was used to characterize residual stresses during cooling in a deliberately engineered resin rich hole of a carbon fiber/RTM6 composite. The residual stress was found to reach approximately 28 MPa, which is in good agreement with the value calculated from the shrinkage and elastic moduli. It is proposed that this simple method can be provide insights useful to the design and materials selection processes by measuring and localizing residual stresses from resin during curing and or thermal cycling.

Abstract—Cluster based protocols like LEACH were found best suited for routing in wireless sensor networks. In mobility centric environments some improvements were suggested in the basic scheme. LEACH-Mobile is one such protocol. The basic LEACH protocol is ...

Bank switching in embedded processors having partitioned memory architecture results in code size as well as run time overhead. An algorithm and its application to assist the compiler in eliminating the redundant bank switching codes introduced and deciding the optimum data allocation to banked memory is presented in this work. A relation matrix formed for the memory bank state transition corresponding to each bank selection instruction is used for the detection of redundant codes. Data allocation to memory is done by ...

This paper presents a performance analysis of reversible, fault tolerant VLSI implementations of carry select and hybrid decimal adders suitable for multi-digit BCD addition. The designs enable partial parallel processing of all digits that perform high-speed addition in decimal domain. When the number of digits is more than 25 the hybrid decimal adder can operate 5 times faster than conventional decimal adder using classical logic gates. The speed up factor of hybrid adder increases above 10 when the number of decimal digits is more than 25 for reversible logic implementation. Such highspeed decimal adders find applications in real time processors and internet-based applications. The implementations use only reversible conservative Fredkin gates, which make it suitable for VLSI circuits.

This paper describes JERIM-320, a new 320-bit hash function used for ensuring message integrity and details a comparison with popular hash functions of similar design. JERIM-320 and FORK-256 operate on four parallel lines of message processing while RIPEMD-320 operates on two parallel lines. Popular hash functions like MD5 and SHA-1 use serial successive iteration for designing compression functions and hence are less secure. The parallel branches help JERIM-320 to achieve higher level of security using multiple iterations and processing on the message blocks. The focus of this work is to prove the ability of JERIM 320 in ensur ing the integrity of messages to a higher degree to suit the fast growing internet applications.

Current research on radio frequency transceivers focuses on multi-standard architectures to attain higher system capacities and data rates. Multiple communication standards are made adaptable by performing channel select filtering on chip at baseband in digital domain. The computationally intensive decimation filter in a sigma-delta analog-to-digital converter plays an important role in channel selection for multi-mode systems. As these architectures are targeted for portable applications, an area and power efficient reconfigurable implementation is an implicit requirement. To this end, a multi-stage, programmable decimation filter based on residue number system (RNS) that is adaptable for WCDMA and WLAN standards is presented in this research. Multi-stage decimation filter implementation offers low computational complexity and power dissipation. The FIR filters of the multi-stage decimator operating in RNS domain offers high data rate because of the carry free operations on smaller residues in parallel channels. Further power saving is achieved by reconfiguring the hardware architecture, and powering down the unused blocks in each mode of operation. For increased programmability modulo multiplication is performed by index addition utilizing the arithmetic benefits associated with Galois field. Finally, a performance comparison of the proposed RNS based decimation filter with traditional binary implementation is done in terms of area, critical path delay and power dissipation.

In this paper we investigate the problem of cache resolution in a mobile peer to peer ad hoc network. In our vision cache resolution should satisfy the following requirements: (i) it should result in low message overhead and (ii) the information should be retrieved with minimum delay. In this paper, we show that these goals can be achieved by splitting the one hop neighbours in to two sets based on the transmission range. The proposed approach reduces the number of messages flooded in to the network to find the requested data. This scheme is fully distributed and comes at very low cost in terms of cache overhead. The experimental results gives a promising result based on the metrics of studies.

This paper discusses our research in developing a generalized and systematic method for anomaly detection. The key ideas are to represent normal program behaviour using system call frequencies and to incorporate probabilistic techniques for classification to detect anomalies and intrusions. Using experiments on the sendmail system call data, we demonstrate that concise and accurate classifiers can be constructed to detect anomalies. An overview of the approach that we have implemented is provided.

This paper discusses the complexities involved in managing and monitoring the delivery of IT services in a multiparty outsourcing environment. The complexities identified are grouped into four categories and are tabulated. A discussion on an attempt to model a multiparty outsourcing scenario using UML is also presented and explained using an illustration. Such a model when supplemented by a performance evaluation tool can enable an organization to manage the provision of IT services in a multiparty outsourcing environment more effectively.

In recent years, reversible logic has emerged as one of the most important approaches for power optimization with its application in low power CMOS, quantum computing and nanotechnology. Low power circuits implemented using reversible logic that provides single error correction-double error detection (SEC-DED) is proposed in this paper. The design is done using a new 4 x 4 reversible gate called 'HCG' for implementing hamming error coding and detection circuits. A parity preserving HCG (PPHCG) that preserves the input parity at the output bits is used for achieving fault tolerance for the hamming error coding and detection circuits.