Search results for " RED"

Online anomaly detection using dimensionality reduction techniques for HTTP log analysis

2015

Modern web services face an increasing number of new threats. Logs are collected from almost all web servers, and for this reason analyzing them is beneficial when trying to prevent intrusions. Intrusive behavior often differs from the normal web traffic. This paper proposes a framework to find abnormal behavior from these logs. We compare random projection, principal component analysis and diffusion map for anomaly detection. In addition, the framework has online capabilities. The first two methods have intuitive extensions while diffusion map uses the Nyström extension. This fast out-of-sample extension enables real-time analysis of web server traffic. The framework is demonstrated using …

An Approach for Network Outage Detection from Drive-Testing Databases

2012

A data-mining framework for analyzing a cellular network drive testing database is described in this paper. The presented method is designed to detect sleeping base stations, network outage, and change of the dominance areas in a cognitive and self-organizing manner. The essence of the method is to find similarities between periodical network measurements and previously known outage data. For this purpose, diffusion maps dimensionality reduction and nearest neighbor data classification methods are utilized. The method is cognitive because it requires training data for the outage detection. In addition, the method is autonomous because it uses minimization of drive testing (MDT) functionalit…

Research literature clustering using diffusion maps

2013

We apply the knowledge discovery process to the mapping of current topics in a particular field of science. We are interested in how articles form clusters and what are the contents of the found clusters. A framework involving web scraping, keyword extraction, dimensionality reduction and clustering using the diffusion map algorithm is presented. We use publicly available information about articles in high-impact journals. The method should be of use to practitioners or scientists who want to overview recent research in a field of science. As a case study, we map the topics in data mining literature in the year 2011. peerReviewed

An Efficient Network Log Anomaly Detection System Using Random Projection Dimensionality Reduction

2014

Network traffic is increasing all the time and network services are becoming more complex and vulnerable. To protect these networks, intrusion detection systems are used. Signature-based intrusion detection cannot find previously unknown attacks, which is why anomaly detection is needed. However, many new systems are slow and complicated. We propose a log anomaly detection framework which aims to facilitate quick anomaly detection and also provide visualizations of the network traffic structure. The system preprocesses network logs into a numerical data matrix, reduces the dimensionality of this matrix using random projection and uses Mahalanobis distance to find outliers and calculate an a…

Genome size evolution in macroparasites.

2014

Reduction in genome size has been associated not only with a parasitic lifestyle in intracellular microparasites but also in some macroparasitic insects and nematodes. We collected the available data on genome size for flatworms, annelids, nematodes and arthropods, compared those with available data for the phylogenetically closest free-living taxa and found evidence of smaller genome sizes for parasites in six of nine comparisons. Our results suggest that despite great differences in evolutionary history and life cycles, parasitism as a lifestyle promotes convergent genome size reduction in macroparasites. We discuss factors that could be associated with small genome size in parasites whic…

Mathematical models and stability analysis of three-phase synchronous machines

2013

Disseny, elaboració i posada en pràctica d'un observatori virtual de codis QR

2012

Durant el curs acadèmic 2011/12 i 2012/13 un grup de professors1, està duent a terme un projecte d'innovació docent que consisteix a dissenyar, produir, implementar i avaluar la idoneïtat dels codis QR en l'ensenyament, utilitzant la xarxa social Facebook2. L'observatori alberga una gran quantitat de codis QR, en funció a la segu?ent taxonomia proposada per l'alumnat participant en l'estudi (alimentació i begudes, art, banca, calçat, cinema, comerços, cura personal, educació, electrodomèstics, esdeveniments, informàtica, immobiliàries, joieria, joguines, llibre, premsa, còmic, logística i transport, parament i decoració, moda, música, obres, papereria, restauració, sanitat, tabac, vehicles,…

Krāsu redzes testa aprobācija datorizētajam redzes skrīningam

2022

Mērķis: veikt datorizēta krāsu redzes testa aprobāciju un novērtēt tā piemērotību krāsu redzes defektu atklāšanā. Pētījumā pirmajā daļā, krāsu redze tika pārbaudīta 74 dalībniekiem vecumā no 20 līdz 50 gadiem, izmantojot datorizēto krāsu redzes skrīninga testu un Richmond HRR testu dienas gaismas apstākļos. Rezultātu atšķirība bija statistiski nozīmīga (p < 0,05). Otrajā pētījuma daļā krāsu redze tika pārbaudīta 26 cilvēkiem vecumā no 20 līdz 24 gadiem, izmantojot anomaloskopu un datorizēto testu tumsas apstākļos. Jaunizveidotais tests uzrādīja augstu precizitāti rezultātos ar anomaloskopu. Tika secināts, ka telpas apgaismojums ietekmē datora testa efektivitāti krāsu redzes defekta noteikša…

Mathematical models and stability analysis of induction motors under sudden changes of load

2013

Red list of threatened vascular plants in Italy

2021

Italy has a rich natural heritage, which is dangerously under pressure. In recent years, there is an increased awareness of the crucial role of plants in ecosystem functioning and in providing ecosystem services. Consequently, an updated Red List of the Italian vascular flora was compiled in this work, at the request of the Ministry for Environment, Land and Sea Protection, with the scientific support of the Italian Botanical Society. The IUCN Red List criteria were applied to 2,430 Italian native vascular plant taxa to assess their current extinction risk and to highlight the major threats affecting the Italian flora. Our results revealed that 54 taxa (2.2% of the assessed taxa) are extinc…