Search results for "Artifacts"

showing 10 items of 105 documents

Numerical expressions for the computation of coincidence-summing correction factors in γ-ray spectrometry with HPGe detectors

2009

Numerical expressions to compute gamma-gamma and gamma-X(K) coincidence summing corrections were deduced by using a suitable computer program and a matrix representation of a decay scheme. For point sources only full-energy peak and total efficiencies are needed. Alternatively, values of peak-to-total ratio can be introduced. For extended sources, the same expressions can be considered with the introduction of "effective efficiencies". Examples of the use of the expressions for point sources and a particulate filter sample measured with a 60% relative efficiency HPGe detector are reported.

RadiationDecay schemeComputer programSettore ING-IND/20 - Misure E Strumentazione NucleariComputationTransducersMatrix representationAnalytical chemistryReproducibility of ResultsEquipment DesignRadiation DosageCoincidence-summingSensitivity and SpecificitySample (graphics)CoincidenceComputational physicsEquipment Failure AnalysisSpectrometry GammaPoint (geometry)g-Ray spectrometryArtifactsRadiometryHpge detectorAlgorithmsMathematicsApplied Radiation and Isotopes
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Optical rogue-wave-like extreme value fluctuations in fiber Raman amplifiers

2008

International audience; We report experimental observation and characterization of rogue wave-like extreme value statistics arising from pump-signal noise transfer in a fiber Raman amplifier. Specifically, by exploiting Raman amplification with an incoherent pump, the amplified signal is shown to develop a series of temporal intensity spikes whose peak power follows a power-law probability distribution. The results are interpreted using a numerical model of the Raman gain process using coupled nonlinear Schrödinger equations, and the numerical model predicts results in good agreement with experiment.

Raman amplificationLightSpectrum Analysis Raman01 natural sciencesNoise (electronics)010309 opticsFour-wave mixingOpticsBrillouin scatteringOscillometry0103 physical sciencesScattering RadiationComputer SimulationRogue wave010306 general physicsExtreme value theoryOptical FibersPhysicsAmplifiers Electronicbusiness.industryCross-phase modulationOptical rogue wavesEquipment DesignModels TheoreticalAtomic and Molecular Physics and OpticsEquipment Failure Analysis[SPI.OPTI]Engineering Sciences [physics]/Optics / PhotonicComputer-Aided Design[ SPI.OPTI ] Engineering Sciences [physics]/Optics / PhotonicbusinessArtifacts
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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.

SesquiterpeneGeneral Chemical EngineeringAllyl compoundMonoterpeneAntimicrobial activityPlant OilEssential oillaw.inventionCamphorchemistry.chemical_compoundlaw(E)-chrysanthenyl acetateChemical Engineering (all)DisulfidesFood scienceMedicinal plantsSicilyFlame IonizationbiologyChemistry (all)food and beveragesGeneral MedicineAntimicrobialAllyl CompoundsArtifactAlliumArtifactsSesquiterpenesArt(Z)-chrysanthenyl acetateSulfideAllium neapolitanumSulfidesGas Chromatography-Mass SpectrometryAlliumBridged Bicyclo CompoundsDisulfideDrug Resistance FungalBotanyDrug Resistance BacterialOils VolatilePlant OilsAllium neapolitanumEssential oilBacteriaFungiGeneral ChemistryPlant Components Aerialbiology.organism_classificationCamphorchemistryMonoterpenesBridged Bicyclo CompoundDimethyl trisulfideAllyl Compound
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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…

Settore ICAR/14 - Composizione Architettonica E UrbanaThe essay questions the future's possibilities to operate on the buildings of the second half of the twentieth century according to the Italian Code of Cultural Heritage (2004-2011). When arguing how to encourage the re-use of these artifacts which are often marked by short-life technology cycles obsolescence and abandonment the ambiguities and inconsistencies of current legislative procedures deeply stress the cultural role of research experiences that use project-oriented methodologies. The comparison between some Italian and other European cases highlights the role of a design approach in the construction of a transformative protection perspective for the built matter of the second half of the twentieth century. In a framework aiming to encourage a reconciliation between the recent built environment and the new paradigms of sustainability and circular economy architecture must recognize re-cycle practices as a main theoretical and procedural node. To modernize the late Modern built environment with contemporary construction components is not simply a matter of technical knowledge and expertise: but a theme with theoretical density aesthetic and ethical values. The architectural project in this field today must ask for greater congruence between the bureaucratic and administrative levels and the real consistency of this corpus. It is a matter of identifying strategies to equip it with capabilities meanings and contents remembering that demolition wastes have unsustainable environmental costs and uncertain results concerning the necessary new attribution of political and semantic meaning that these places await.
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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…

Settore ING-INF/05 - Sistemi Di Elaborazione Delle InformazioniArtifact (error)rf-inhomogeneity bias artifact mribusiness.industryAttenuationFeature extractionReproducibility of ResultsSignal Processing Computer-AssistedImage EnhancementMagnetic Resonance ImagingSensitivity and SpecificitySignalSample (graphics)LuminanceGabor filterImage Interpretation Computer-AssistedComputer visionArtificial intelligenceArtifactsbusinessAlgorithmsImage restorationMathematics
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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 (…

Settore ING-INF/05 - Sistemi Di Elaborazione Delle InformazioniPolynomialArtifact (error)Brain MappingMRI rf-inhomogeneity homomorphic unsharp masking bias artifactbusiness.industryEntropyModels NeurologicalStreakBrainImage segmentationInformation theoryExpectation–maximization algorithmImage Processing Computer-AssistedHumansComputer visionSegmentationArtificial intelligencebusinessArtifactsAlgorithmAlgorithmsUnsharp maskingMathematics
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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).

Settore L-ANT/10 - Metodologie Della Ricerca ArcheologicaMazzarino Sicily African artifacts V-VI AD Macharina
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Santa Venera e la Pace: secoli di devozione, storia, cultura e società a Palermo

2021

Si tratta di un saggio introduttivo al volume sulla compagnia della Pace con le relative opere d'arte e d'architettura volute da committenza preclara siciliana per la sede palermitana dell'organismo. Il saggio tira le fila dei contributi presenti nel volume offrendo alcune ipotesi interpretative aggiuntive su alcuni manufatti artistici e definendo i contesti culturali di alcuni interventi e della relativa aristocratica committenza. This is an introductory essay to the volume on the company of Peace with the related works of art and architecture commissioned by Sicilian preclars for the Palermo headquarters of the organism. The essay pulls the strings of the contributions present in the volu…

Settore L-ART/04 - Museologia E Critica Artistica E Del Restauroworks of art and architectureartistic artifactsaristocratic clientarte architettura committenza aristocrazia manufatti
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RNA marker modifications reveal the necessity for rigorous preparation protocols to avoid artifacts in epitranscriptomic analysis

2021

Abstract The accurate definition of an epitranscriptome is endangered by artefacts resulting from RNA degradation after cell death, a ubiquitous yet little investigated process. By tracing RNA marker modifications through tissue preparation protocols, we identified a major blind spot from daily lab routine, that has massive impact on modification analysis in small RNAs. In particular, m6,6A and Am as co-varying rRNA marker modifications, appeared in small RNA fractions following rRNA degradation in vitro and in cellulo. Analysing mouse tissue at different time points post mortem, we tracked the progress of intracellular RNA degradation after cell death, and found it reflected in RNA modific…

Small RNAProgrammed cell deathRNABiologyRibosomal RNAIn vitroCell biologyCortex (botany)MiceRNA TransferRNA RibosomalTransfer RNAGeneticsAnimalsRNARNA Processing Post-TranscriptionalArtifactsIntracellularNucleic Acids Research
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Design e narrazioni

2022

Il testo nasce dall’esigenza di mettere a fuoco le implicazioni cognitive, metodologiche e progettuali del concetto di narrazione, sempre più ricorrente nella nostra esperienza quotidiana soprattutto per le molteplici forme di comunicazione e di produzioni culturali che vi si ispirano; si tratta di un concetto che anche nella riflessione teorica e nella progettualità del design sta alimentando dimensioni fortemente innovative ed evolutive nella costruzione, comunicazione di significati, contenuti immateriali, esperienze e valori emozionali che si sovrappongono e s’intrecciano all’espressione tangibile e funzionale degli oggetti, degli artefatti comunicativi, degli spazi. Si propone un perco…

The text arises from the need to focus on the cognitive methodological and design implications of the concept of storytelling increasingly recurrent in our daily experience especially for the many forms of communication and cultural productions that are inspired by itSettore ICAR/13 - Disegno Industrialeit is a concept that also in theoretical reflection and design planning is feeding strongly innovative and evolutionary dimensions in the construction communication of meanings intangible content experiences and emotional values that overlap and intertwine with the tangible and functional expression of objects communicative artifacts spaces.. It proposes a cognitive path tangent to the development of "narratology" and the theories of narrationthus we come across a multiplicity of disciplinary connections affecting sociology psychology anthropology philosophy semiotics and of course history cinema journalism advertising up to corporate communication and political propaganda. It is an articulated panorama that today seems to expand more and more and far from being mainly addressed to theoretical issues increasingly seems to be modeled on application performative and design aspects.
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