Search results for "Artifact"
showing 10 items of 193 documents
Through a Glass, Darkly
2013
Political actors increasingly use the microblogging service, Twitter, for the organization, coordination, and documentation of collective action. These interactions with Twitter leave digital artifacts that can be analyzed. In this article, we look at Twitter messages commenting on one of the most contentious protests in Germany’s recent history, the protests against the infrastructure project Stuttgart 21. We analyze all messages containing the hashtag #s21 that were posted between May 25, 2010, and November 14, 2010, by the 80,000 most followed Twitter users in Germany. We do this to answer three questions: First, what distinguishes events that resulted in high activity on Twitter from ev…
Composition of the essential oil of allium neapolitanum cirillo growing wild in sicily and its activity on microorganisms affecting historical art cr…
2015
Essential oil of the aerial parts of Allium neapolitanum Cirillo collected in Sicily were analyzed by gas-chromatography-flame-ionization detection and gas-chromatography-mass spectrometry. Nineteen compounds were identified in the oil and the main components were found to be (E)-chrysanthenyl acetate (28.1%), (Z)-chrysanthenyl acetate (23.8%), (E)-β-farnesene (9.6%), dimethyl trisulfide (9.6%), camphor (7.4%), methyl allyl disulfide (6.8%) and 1-methyl-3-allyl trisulfide (5.8%). The essential oil showed good antimicrobial activity against 11 strains of test microorganisms, including several species infesting historical material.
Sine cura. Verso il ri-ciclo dell'architettura del secondo Novecento
2019
Gli argomenti discussi nel saggio interrogano il destino che il Codice dei Beni Culturali (2004- 2011) determina per le opere del secondo Novecento. Nella costruzione del futuro di questi manufatti, che per funzione, tecnologia e cicli d’uso sono spesso segnati dall’obsolescenza e dall’abbandono, le ambiguità e le incongruenze delle attuali procedure legislative sollecitano profondamente il ruolo culturale delle esperienze di ricerca che usano metodologie meta progettuali. Il confronto fra alcuni casi italiani ed altri europei rimarca il ruolo del progetto nella costruzione di una prospettiva di tutela trasformativa per il costruito del secondo Novecento. Nel quadro di azione marcato dall’o…
Segmentation of MR brain images with bias artifact
2009
Brain MR Images corrupted by RF- Inhomogeneity (bias artifact) exhibit brightness variations across the image. As a consequence, a standard Fuzzy C-Means (fern) segmentation algorithm may fail. In this work we show a new general-purpose bias removing algorithm, which can be used as a pre-processing step for a fern segmentation. We also compare our experimental results with the ones achieved by using E2 D - H U M filter, showing an improvement in brain segmentation and bias removal.
A Gabor-based Technique for Bias Removal in MR images
2007
Magnetic Resonance images are often characterized by irregularly displaced luminance fluctuations that are called bias artifact. This disturb is due to a drop in signal intensity caused by the distance between imaged sample and receiver coil. An original approach to bias removal in Magnetic Resonance images is presented, which is based on the use of Gabor filter to extract the artifact. The proposed technique restores the image using a correction model, which is derived from the attenuation of signal diffusion across the tissues. No hypotheses are made about the structure of the tissues under investigation and the used MR spectrum. The approach is presented in detail, and extensive experime…
Homomorphic Approach to RF-Inhomogeneity Removal Based on Gabor Filter
2007
In this paper a bias correction algorithm for magnetic resonance imaging (MRI) is presented. The magnetic resonance (MR) images affected by this artifact, also called RF-inhomogeneity, exhibit irregular spatial brightness variations caused by magnetic field inhomogeneity. Here we present an original algorithm based on E2D - HUM, already proposed by some of the authors, where a modified Gabor filter is introduced in the elaboration chain to provide directional capabilities to suppress the artifact. The process of restoration doesn't care about the structure of the image and it has been applied to MR images of different parts of body like knee, abdomen, pelvis and brain. A comparison with oth…
Multimodal virtual navigation of a cultural heritage site: The medieval ceiling of Steri in Palermo
2009
The advance of information technology has enabled in recent years new fruition scenarios for cultural heritage sites. Multidisciplinary approaches integrate survey techniques with multimodal interfaces to allow enhanced fruition for larger group of users. In this paper we propose a multimodal interface to a virtual representation of a medieval ceiling, built in the XIV century, which covers the “Sala Magna” of Steri, the historical headquarters of the University of Palermo, in Italy. This research deals with the definition of a process for the integration of surveying techniques, modelling processes and communication technologies for the documentation of such artifacts. This is a two-stage …
Morphological exponential entropy driven-HUM.
2006
This paper presents an improvement to the Ex- ponential Entropy Driven - Homomorphic Unsharp Masking (E 2 D − HUM ) algorithm devoted to illumination artifact sup- pression on Magnetic Resonance Images. E 2 D−HUM requires a segmentation step to remove dark regions in the foreground whose intensity is comparable with background, because strong edges produce streak artifacts on the tissues. This new version of the algorithm keeps the same good properties of E 2 D − HUM without a segmentation phase, whose parameters should be chosen in relation to the image. I. INTRODUCTION Most of the studies on illumination correction found in literature are oriented to brain (18) magnetic resonance images (…
A Methodology for Graphical Modeling of Business Rules
2011
This work proposes a novel methodology based on the Business Process Modeling Notation (BPMN) standard capable of graphically modeling business rules. A set of new representation patterns allows business analysts to map processes described through BPMN into conditions and actions of business rules. Our approach exploits Domain Specific Language techniques in order to make the methodology independent from the programming language supported by the specific rule engine. Moreover, this work proposes a web graphical editor, instantiated on a specific sample scenario, where the selected rule engine is Drools, one of the most used open source products. The developed editor allows business analysts…
Mazzarino (CL), contrada Minnelli (sito 41)
2016
The contribution illustrates the site of Contrada Minnelli, in the territory of Mazzarino, which has returned a settlement intended for handicraft production, frequented between the 5th and 6th centuries AD, probably to be identified with the site of Macharina mentioned by the sources. Particular attention is paid to the artifacts of African production found (amphoras, lamps, fragments of sigillata).