Search results for "Server"
showing 10 items of 586 documents
Improving clustering of Web bot and human sessions by applying Principal Component Analysis
2019
View references (18) The paper addresses the problem of modeling Web sessions of bots and legitimate users (humans) as feature vectors for their use at the input of classification models. So far many different features to discriminate bots’ and humans’ navigational patterns have been considered in session models but very few studies were devoted to feature selection and dimensionality reduction in the context of bot detection. We propose applying Principal Component Analysis (PCA) to develop improved session models based on predictor variables being efficient discriminants of Web bots. The proposed models are used in session clustering, whose performance is evaluated in terms of the purity …
Evaluation of retro-reflective coating performance by reflectance and perceived relative brightness measurements
2011
Retro-reflective properties of six types and five different colors or retro-reflective materials were discussed in this paper. Reflectance optical indicatrix of samples was determined and compared to obtained psychophyisical data of perceived brightness of human observer. Microscopic structure of the retro-reflective active regions of RR's was studied. Statistically significant differences in reflectivity and brightness of various types and colors of RR's were found.
Prevalence and factors associated with bullying phenomenon among pre-adolescents attending first-grade secondary schools of Palermo, Italy, and a com…
2021
Abstract Background Bullying is recognized as one of the most significant social and health problems in the school environment for children and adolescents. In Italy, bullying involved 2 in 10 kids between 11–17 years that referred to have been bullied two or more times in a month. In Sicily, the estimated prevalence of children aged 11 to 15 that suffered at least one act of bullying in the last two months was 14% in 2011. Methods A questionnaire consisting of 30 items investigating physical, verbal and indirect bullying, observers of bullying, resiliency, and prosociality was administered to preadolescents of ten first-grade secondary schools within the Palermo Province in order to analyz…
Gossip
2019
Nowadays, a growing number of servers and workstations feature an increasing number of GPUs. However, slow communication among GPUs can lead to poor application performance. Thus, there is a latent demand for efficient multi-GPU communication primitives on such systems. This paper focuses on the gather, scatter and all-to-all collectives, which are important operations for various algorithms including parallel sorting and distributed hashing. We present two distinct communication strategies (ring-based and flow-oriented) to generate transfer plans for their topology-aware implementation on NVLink-connected multi-GPU systems. We achieve a throughput of up to 526 GB/s for all-to-all and 148 G…
Improved inter-observer agreement of an expert review panel in an oncology treatment trial--Insights from a structured interventional process.
2015
Abstract Purpose Oncologic imaging is a key for successful cancer treatment. While the quality assurance (QA) of image acquisition protocols has already been focussed, QA of reading and reporting offers still room for improvement. The latter was addressed in the context of a prospective multicentre trial on fluoro-deoxyglucose (FDG)–positron-emission tomography (PET)/CT-based chemoradiotherapy for locally advanced non-small cell lung cancer (NSCLC). Material and methods An expert panel was prospectively installed performing blinded reviews of mediastinal NSCLC involvement in FDG–PET/CT. Due to a high initial reporting inter-observer disagreement, the independent data monitoring committee (I…
Transcriptome-wide identification of transient RNA G-quadruplexes in human cells
2018
Guanine-rich RNA sequences can fold into four-stranded structures, termed G-quadruplexes (G4-RNAs), whose biological roles are poorly understood, and in vivo existence is debated. To profile biologically relevant G4-RNA in the human transcriptome, we report here on G4RP-seq, which combines G4-RNA-specific precipitation (G4RP) with sequencing. This protocol comprises a chemical crosslinking step, followed by affinity capture with the G4-specific small-molecule ligand/probe BioTASQ, and target identification by sequencing, allowing for capturing global snapshots of transiently folded G4-RNAs. We detect widespread G4-RNA targets within the transcriptome, indicative of transient G4 formation in…
A study on the reproducibility of cephalometric landmarks when undertaking a three-dimensional (3D) cephalometric analysis
2012
Objectives: Cone Beam Computerized Tomography (CBCT) allows the possibility of modifying some of the diagnostic tools used in orthodontics, such as cephalometry. The first step must be to study the characteristics of these devices in terms of accuracy and reliability of the most commonly used landmarks. The aims were 1- To assess intra and inter-observer reliability in the location of anatomical landmarks belonging to hard tissues of the skull in images taken with a CBCT device, 2- To determine which of those landmarks are more vs. less reliable and 3- To introduce planes of reference so as to create cephalometric analyses appropriated to the 3D reality. Study design: Fifteen patients who h…
Model and optimal Call Admission Policy in Cellular Mobile Networks
2000
For current cellular networks, two important Quality of Service (QoS) measures are the fractions of new and handoff calls that are blocked due to unavailability of channels. Based on these QoS measures, we propose a queuing network model with impatient users for handoff and new calls in cellular mobile networks. The number of simultaneous calls, that can be supported, is modeled by C identical servers with exponentially distributed session duration for each one of them. Priority is given to handoffs over new calls. We use for that a Guard Channel policy that reserves a set of CH channels for handoff calls, new calls being served at their arrival if there are more than CH available channels.…
The Mona Lisa effect: Testing the limits of perceptual robustness vis-à-vis slanted images
2014
We report three experiments that test the limits of the Mona Lisa effect. The gaze of a portrait that is looking at us appears to follow us around as we move with respect to the picture. Even if our position is shifted considerably to the side, or if the picture is severely slanted, do we feel the gaze to be directed at us? We determined the threshold where this effect breaks down to be maximally 70? of picture slant relative to the observer. Different factors modulate this remarkable robustness, among them being the display medium and the nature of the picture. The threshold was considerably lower when the picture was mounted on a physical surface as opposed to a computer simulation of sla…
Exploring relationships between pianists’ body movements, their expressive intentions, and structural elements of the music
2011
Body movements during music performance have been found to be indicative of the performer’s musical intentionality, and contribute to an observer’s perception of expressive playing. This study investigates the effect of structural elements of the score, and the playing of different levels of expression on body movements during a piano performance. Pianists were required to play the same piece in four different performance conditions. Their movements were tracked by an optical motion capture system, and the comparisons that were made between specific parts of the body used, performance condition, and musical score locations were subsequently statistically examined. We found that the head an…