Search results for "Abstract"
showing 10 items of 1959 documents
Deriving and comparing deduplication techniques using a model-based classification
2015
Data deduplication has been a hot research topic and a large number of systems have been developed. These systems are usually seen as an inherently linked set of characteristics. However, a detailed analysis shows independent concepts that can be used in other systems. In this work, we perform this analysis on the main representatives of deduplication systems. We embed the results in a model, which shows two yet unexplored combinations of characteristics. In addition, the model enables a comprehensive evaluation of the representatives and the two new systems. We perform this evaluation based on real world data sets.
Mobile agents, globus and resource discovery
2004
Publisher Summary This chapter discusses grid technology and some related problem. The overview of grids, in terms of application fields and needed protocols is given. The common feature of all grid architectures is a coordinated and controlled resource sharing between the members of a dynamic multi-institutional virtual community. The members of such a community agree on which resources will be shared and which members of the community will be enabled to access these resources, thus defining a set of sharing rules and permissions. The Globus project is discussed, which is nowadays the de facto standard for grid environments, with emphasis on its resource discovery components. Finally, the …
Detection and Isolation of Switches in Point Clouds of the German Railway Network
2015
In order to obtain an automated system of railway management, it is necessary to automatically detect, isolate and identify all switches in a point cloud which represents the railway. To realize this automated system of detection, a set of pre-processing steps is applied. The system begins by detecting and isolating tracks through application of a mask on each section of the point cloud. Then, it does a denoising through mathematical morphology and a compression in replacing a group of points by their centroid. Finally, it closes tracks holes through extrapolation. After that, the system does a low-level processing to search for all intersections between tracks, and records information on t…
Validation of Predictive Approaches for Ductile Fracture in Cold Extrusion
1999
Cold extrusion is sometimes accompanied by some typical internal defects, known in the technical literature as “central bursts”, which dramatically could affect the component behaviour during its service life. Several researchers, following both analytical and numerical approaches have attempted central bursting prediction in extrusion. Among the latter several approaches have been proposed in the literature, namely the ones based on the use of ductile fracture criteria and the ones founded on the damage mechanics analysis. Each one of these approaches presents some advantages and drawbacks. In the paper the authors analyze a set of cold extrusion processes on AISI 1040 specimens at varying…
PARAMETER BOUNDED ESTIMATION FOR QUASISPECIES MODELS OF MOLECULAR EVOLUTION
2006
Abstract The Quasispecies models identification for Evolutionary Dynamics is considered in a worst-case deterministic setting. These models analyze the DNA and RNA evolution or describe the population dynamics of viruses and bacteria. In this paper we identify the Fitness and the Replication Probability parameters of a genetic sequences, subject to a set of stringent constraints to have physical meaning and to guarantee positiveness. The conditional central estimate and the Uncertainty Intervals are determined. The effectiveness of the proposed procedure has been illustrated by means of simulation experiments while tests on real data are under concern.
Detection of Anomalous HTTP Requests Based on Advanced N-gram Model and Clustering Techniques
2013
Nowadays HTTP servers and applications are some of the most popular targets for network attacks. In this research, we consider an algorithm for HTTP intrusions detection based on simple clustering algorithms and advanced processing of HTTP requests which allows the analysis of all queries at once and does not separate them by resource. The method proposed allows detection of HTTP intrusions in case of continuously updated web-applications and does not require a set of HTTP requests free of attacks to build the normal user behaviour model. The algorithm is tested using logs acquired from a large real-life web service and, as a result, all attacks from these logs are detected, while the numbe…
Homogeneous Suslinian Continua
2011
AbstractA continuumis said to be Suslinian if it does not contain uncountably many mutually exclusive non-degenerate subcontinua. Fitzpatrick and Lelek have shown that a metric Suslinian continuum X has the property that the set of points at which X is connected im kleinen is dense in X. We extend their result to Hausdorff Suslinian continua and obtain a number of corollaries. In particular, we prove that a homogeneous, non-degenerate, Suslinian continuum is a simple closed curve and that each separable, non-degenerate, homogenous, Suslinian continuum is metrizable.
An Introduction to Computational Complexity
2016
This chapter is not strictly about algebra. However, this chapter offers a set of mathematical and computational instruments that will allow us to introduce several concepts in the following chapters. Moreover, the contents of this chapter are related to algebra as they are ancillary concepts that help (and in some cases allow) the understanding of algebra.
Segmentation and feature extraction in capillaroscopic videos
2015
This contribution describes a method to select regions of interest as capillaries of the oral mucosa and to extract their main features useful for real diagnosis purposes. A discrete version of the wavelet transform has been adopted for segmenting the images coming from video sequences acquired by a prototype capillaroscopic, able to put in evidence the red blood flow. A set of proper characteristics is automatically computed for a correct evaluation of the peripheral microcirculation.
M-VIF: A machine-vision based on information fusion
2002
The authors describe a new architecture for machine vision, which is based on information fusion approach. Its general design has been developed by using a formal computation model that integrates three main ingredients of the visual computation: the data, the models, and the algorithms. The hardware design and the software environment of M-VIF are also given. The simulation of M-VIF is under development on the HERMIA-machine.