25 research outputs found
A Comparative study of Arabic handwritten characters invariant feature
This paper is practically interested in the unchangeable feature of Arabic
handwritten character. It presents results of comparative study achieved on
certain features extraction techniques of handwritten character, based on Hough
transform, Fourier transform, Wavelet transform and Gabor Filter. Obtained
results show that Hough Transform and Gabor filter are insensible to the
rotation and translation, Fourier Transform is sensible to the rotation but
insensible to the translation, in contrast to Hough Transform and Gabor filter,
Wavelets Transform is sensitive to the rotation as well as to the translation
Towards trusted volunteer grid environments
Intensive experiences show and confirm that grid environments can be
considered as the most promising way to solve several kinds of problems
relating either to cooperative work especially where involved collaborators are
dispersed geographically or to some very greedy applications which require
enough power of computing or/and storage. Such environments can be classified
into two categories; first, dedicated grids where the federated computers are
solely devoted to a specific work through its end. Second, Volunteer grids
where federated computers are not completely devoted to a specific work but
instead they can be randomly and intermittently used, at the same time, for any
other purpose or they can be connected or disconnected at will by their owners
without any prior notification. Each category of grids includes surely several
advantages and disadvantages; nevertheless, we think that volunteer grids are
very promising and more convenient especially to build a general multipurpose
distributed scalable environment. Unfortunately, the big challenge of such
environments is, however, security and trust. Indeed, owing to the fact that
every federated computer in such an environment can randomly be used at the
same time by several users or can be disconnected suddenly, several security
problems will automatically arise. In this paper, we propose a novel solution
based on identity federation, agent technology and the dynamic enforcement of
access control policies that lead to the design and implementation of trusted
volunteer grid environments.Comment: 9 Pages, IJCNC Journal 201
Grid’5000 Based Large Scale OCR Using the DTW Algorithm: Case of the Arabic Cursive Writing
International audienc
PKI and UDDI based trust centre: an attempt to improve web service security
4 pagesInternational audienceNowadays Internet becomes the most used tool for the ever increasing amount of various transactions between institutions, organizations and more generally between clients and providers. Conducted studies and experiments showed that it is more convenient to provide and achieve these transactions as web services (WS) to guarantee their flexibility and their reuse. So far these services and the corresponding providers' URLs are advertised on specific UDDIs (Universal Description, Discovery and Integration). As such, after finding the requested service any given client contacts the right provider to negotiate the service access procedure. These first contacts between clients and providers are usually and ommonly not protected (Encrypted) yielding enough room for Hackers to intrude into these unprotected messages. In this paper, we propose a securing approach based on both the PKI nfrastructure and some proposed improvements of the UDDI functioning in an attempt to provide adequate security for web service
Graph-based methods for Significant Concept Selection
It is well known in information retrieval area that one important issue is the gap between the query and document vocabularies. Concept-based representation of both the document and the query is one of the most effective approaches that lowers the effect of text mismatch and allows the selection of relevant documents that deal with the shared semantics hidden behind both. However, identifying the best representative concepts from texts is still challenging. In this paper, we propose a graph-based method to select the most significant concepts to be integrated into a conceptual indexing system. More specifically, we build the graph whose nodes represented concepts and weighted edges represent semantic distances. The importance of concepts are computed using centrality algorithms that levrage between structural and contextual importance. We experimentally evaluated our method of concept selection using the standard ImageClef2009 medical data set. Results showed that our approach significantly improves the retrieval effectiveness in comparison to state-of-the-art retrieval models
Reconnaissance de caracteres imprimes par comparaison dynamique
SIGLECNRS T Bordereau / INIST-CNRS - Institut de l'Information Scientifique et TechniqueFRFranc
TOWARDS AN OPTIMAL UTILIZATION OF VOLUNTEER GRID COMPUTING: A COMPARATIVE STUDY OF THREE HEURISTICS
ABSTRAC
Performance Evaluation of the distributed Arabic cursive characters recognition using the DTW algorithm on the SRTG
Arabic printed cursive characters Recognition using the Dynamic Time Warping (DTW) algorithm provides very interesting results. Unfortunately, the big amount of computing to be achieved by this algorithm during the recognition process makes its execution time very slow. Grid computing presents a very interesting infrastructure that allow to support distributed applications in one hand and to take advantages of the underlying unutilized computing and/or the storage power in the other hand. Thus, we present in this paper the performance analysis of the distribution of the DTW algorithm on the Scientific Research Tunisian Grid (SRTG). Obtained preliminary results confirm that the Scientific Research Tunisian Grid gives an interesting framework to speedup greedy algorithms such as the DTW