Search results for "DETECT"
showing 10 items of 5902 documents
Photodétecteurs UV à base GaAlN
2004
Trigger and aperture of the surface detector array of the Pierre Auger Observatory
2010
The surface detector array of the Pierre Auger Observatory consists of 1600 water-Cherenkov detectors, for the study of extensive airshowers (EAS) generated by ultra-high-energy cosmic rays. We describe the trigger hierarchy, from the identification of candidates howers at the level of a single detector, amongst a large background (mainly random single cosmic ray muons), up to the selection of real events and the rejection of random coincidences. Such trigger makes the surface detector array fully efficient for the detection of EAS with energy above 3 x 1018 eV, for all zenith angles between 03 and 603, independently of the position of the impact point and of the mass of the primary particl…
Modeling, Design and Experimentation of Wearable RFID Sensor Tag
2010
Design of effective wearable tags for UHF RFID applications involving persons is still an open challenge due to the strong interaction of the antenna with the human body which is responsible of impedance detuning and efficiency degradation. A new tag geometry combining folded conductors and tuning slots is here discussed through numerical analysis and extensive experimentation also including the integration of a passive motion detector. The achieved designs, having size comparable with a credit card, may be applied to any part of the body. The measured performance indicates a possible application of these body-worn tags for the continuous tracking of human movements in a conventional room.
Occurrence of priority pollutants in WWTP effluents and Mediterranean coastal waters of Spain
2011
A comprehensive study aimed at evaluating the occurrence, significance of concentrations and spatial distribution of priority pollutants (PPs) along the Comunidad Valenciana coastal waters (Spain) was carried out in order to fulfil the European Water Framework Directive (WFD). Additionally, PP concentrations were also analysed in the effluent of 28 WWTPs distributed along the studied area. In coastal waters 36 organic pollutants of the 71 analysed, including 26 PPs were detected although many of them with low frequency of occurrence. Only 13 compounds, which belong to four different classes (VOCs, organochlorinated pesticides, phthalates and tributyltin compounds (TBT)) showed a frequency o…
Intruder Pattern Identification
2008
This paper considers the problem of intrusion detection in information systems as a classification problem. In particular the case of masquerader is treated. This kind of intrusion is one of the more difficult to discover because it may attack already open user sessions. Moreover, this problem is complex because of the large variability of user models and the lack of available data for the learning purpose. Here, flexible and robust similarity measures, suitable also for non-numeric data, are defined, they will be incorporated on a one-class training K N N and compared with several classification methods proposed in the literature using the Masquerading User Data set (www.schonlau.net) repr…
Implementation and performance of the ATLAS second level jet trigger
2008
ATLAS is one of the four major LHC experiments, designed to cover a wide range of physics topics. In order to cope with a rate of 40 MHz and 25 interactions per bunch crossing, the ATLAS trigger system is divided in three different levels. The first one (LVL1, hardware based) identifies signatures in 2 microseconds that are confirmed by the the following trigger levels (software based). The Second Level Trigger (LVL2) only looks at a region of the space around the LVL1 signature (called Region of Interest or ROI), confirming/rejecting the event in about 10 ms, while the Event Filter (Third Level Trigger, EF) has potential full event access and larger processing times, of the order of 1 s. T…
Bot recognition in a Web store: An approach based on unsupervised learning
2020
Abstract Web traffic on e-business sites is increasingly dominated by artificial agents (Web bots) which pose a threat to the website security, privacy, and performance. To develop efficient bot detection methods and discover reliable e-customer behavioural patterns, the accurate separation of traffic generated by legitimate users and Web bots is necessary. This paper proposes a machine learning solution to the problem of bot and human session classification, with a specific application to e-commerce. The approach studied in this work explores the use of unsupervised learning (k-means and Graded Possibilistic c-Means), followed by supervised labelling of clusters, a generative learning stra…
The Upgrade of the ATLAS Level-1 Central Trigger Processor
2013
The ATLAS Level-1 Central Trigger Processor (CTP) combines information from calorimeter and muon trigger processors as well as other sources and makes the final Level-1 Accept (L1A) decision. Due to the increasing luminosity of the LHC and the growing demands of physics and monitoring placed on the ATLAS Level-1 trigger system, the current CTP has reached its design limits. Therefore and in order to provide some margin for future operation, the CTP will be upgraded during the LHC shutdown of 2013/14.
The SuperK-Gd Project
2018
The SuperK-Gd project is the proposed and approved upgrade of the Super-Kamiokande detector in order to enable it to efficiently detect thermal neutrons. The project consists in dissolving a Gd salt into SK at a concentration of 0.2%.
Fibronectin urothelial gene expression as a new reliable biomarker for early detection of local toxicity secondary to adjuvant intravesical therapy f…
2020
Background: A marker of urothelial damage could be helpful for early detection and monitoring of local toxicity due to intravesical therapy for non-muscle invasive bladder cancer (NMIBC). The aim of the study was to investigate the correlation between fibronectin (FN) gene expression in bladder washings and local toxicity secondary to adjuvant intravesical therapy. Materials and methods: Patients undergoing adjuvant intravesical therapy for NMIBC and age-matched healthy patients were enrolled. Real time polymerase chain reaction was performed to analyze FN expression in bladder washings. Local toxicity was classified as: 0–1 mild (no medical therapy), 2 moderate (medical therapy and/or inst…