Search results for "Discrete"

showing 10 items of 2205 documents

Dense Geometry of Music and Visual Arts: Vanishing Points, Continuous Tonnetz, and Theremin Performance

2018

The dualism between continuous and discrete is relevant in music theory as well as in performance practice of musical instruments. Geometry has been used since longtime to represent relationships between notes and chords in tonal system. Moreover, in the field of mathematics itself, it has been shown that the continuity of real numbers can arise from geometrical observations and reasoning. Here, we consider a geometrical approach to generalize representations used in music theory introducing continuous pitch. Such a theoretical framework can be applied to instrument playing where continuous pitch can be naturally performed. Geometry and visual representations of concepts of music theory and…

Settore FIS/02 - Fisica Teorica Modelli E Metodi MatematiciSettore INF/01 - Informaticamedia_common.quotation_subject05 social sciencesSettore ING-INF/02 - Campi Elettromagnetici06 humanities and the artsArtSettore MAT/04 - Matematiche ComplementariContinuum and discrete music theory050105 experimental psychology060404 musicComputer graphics (images)0501 psychology and cognitive sciencesVanishing pointTonnetz0604 artsmedia_common
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A memetic approach to discrete tomography from noisy projections

2010

Discrete tomography deals with the reconstruction of images from very few projections, which is, in the general case, an NP-hard problem. This paper describes a new memetic reconstruction algorithm. It generates a set of initial images by network flows, related to two of the input projections, and lets them evolve towards a possible solution, by using crossover and mutation. Switch and compactness operators improve the quality of the reconstructed images during each generation, while the selection of the best images addresses the evolution to an optimal result. One of the most important issues in discrete tomography is known as the stability problem and it is tackled here, in the case of no…

Settore INF/01 - InformaticaCrossoverComputingMethodologies_IMAGEPROCESSINGANDCOMPUTERVISIONEvolutionary algorithmDiscrete tomographyReconstruction algorithmImage processingIterative reconstructionStability problemArtificial IntelligenceRobustness (computer science)Signal ProcessingMemetic algorithmComputer Vision and Pattern RecognitionDiscrete tomographyAlgorithmSoftwareEvolutionary reconstruction.MathematicsPattern Recognition
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Graph-based minimal path tracking in the skeleton of the retinal vascular network

2012

This paper presents a semi-automatic framework for minimal path tracking in the skeleton of the retinal vascular network. The method is based on the graph structure of the vessel network. The vascular network is represented based on the skeleton of the available segmented vessels and using an undirected graph. Significant points on the skeleton are considered nodes of the graph, while the edge of the graph is represented by the vessel segment linking two neighboring nodes. The graph is represented then in the form of a connectivity matrix, using a novel method for defining vertex connectivity. Dijkstra and Floyd-Warshall algorithms are applied for detection of minimal paths within the graph…

Settore INF/01 - Informaticabusiness.industryComputer sciencePath trackingGraph theoryImage segmentationGraph bandwidthRetinal Images Graphs Dijkstra Floyd-WarshallGraph (abstract data type)Computer visionArtificial intelligencebusinessBeta skeletonDijkstra's algorithmAlgorithmRandom geometric graphMathematicsofComputing_DISCRETEMATHEMATICS2012 25th IEEE International Symposium on Computer-Based Medical Systems (CBMS)
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Lagrangian simulation of bubbling dynamics in a lab-scale 2D fluidized bed

2013

The present work focuses on the development of a novel computational code able to predict with a reasonable level of accuracy the bubble behavior in gas fluidized beds with minimum computational demands. The code simulates the bubble chaotic rise motion and coalescence along bed height via simple lagrangian tracking of bubbles. An original empirical model for the assessment of bubble-bubble interactions is developed. The code is used to simulate a lab-scale unit in bubbling and slugging mode. On this basis, fast simulations are performed to successfully predict bubble population and fluxes within the bed. The main aim of this code is to be embedded within CAPE codes for the process simulati…

Settore ING-IND/26 - Teoria Dello Sviluppo Dei Processi Chimicinumerical simulationdiscrete bubble modelmodeling2D
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A combined CWT-DWT method using model-based design simulator for partial discharges online detection

2009

The suppression of noises is fundamental in onsite Partial Discharge (PD) measurements. For this purpose, the wavelet transform analysis method has been developed and it is a powerful tool for processing the transient and suddenly changing signals. As the wavelet transform possesses the properties of multi-scale analysis and time-frequency domain localization, it is also particularly suitable to process the suddenly changing signals of the partial discharge pulse (PD). In this paper, an improved Wavelet denoising method developed by a model-based design software is presented. Simulations are provided as well as some results obtained during laboratory experiment and on-line PD measurements. …

Settore ING-IND/31 - ElettrotecnicaWaveletComputer scienceNoise reductionPartial dischargeModel-based designdiscrete wavelet transforms partial discharge measurements time-frequency analysis transientsElectronic engineeringSoftware designWavelet transformContinuous wavelet transformTime–frequency analysis2009 IEEE Conference on Electrical Insulation and Dielectric Phenomena
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Telecom-compatible, affordable and scalable quantum technologies

2022

The realistic implementation of quantum architectures relies on the development of scalable, resource-efficient platforms that are compatible with CMOS technologies as well as fiber networks. This work demonstrates novel schemes utilized for time-/frequency-bin entanglement generation and processing by leveraging existing telecommunications and integrated photonics infrastructures.

Settore ING-INF/02 - Campi ElettromagneticiIntegrated quantum optics complex photon states quantum frequency combs silicon-based chips microring resonators spiral waveguides integrated Mach-Zehnder interferometers discrete time and frequency modes photonic qubits and qudits
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Clifford Rotors for Conceptual Representation in Chatbots

2013

In this abstract we introduce an unsupervised sub-symbolic natural language sentences encoding procedure aimed at catching and representing into a Chatbot Knowledge Base (KB) the concepts expressed by an user interacting with a robot. The chatbot KB is coded in a conceptual space induced from the application of the Latent Semantic Analysis (LSA) paradigm on a corpus of documents. LSA has the effect of decomposing the original relationships between elements into linearly-independent vectors. Each basis vector can be considered therefore as a "conceptual coordinate", which can be tagged by the words which better characterize it. This tagging is obtained by performing a (TF-IDF)-like weighting…

Settore ING-INF/05 - Sistemi Di Elaborazione Delle InformazioniDiscrete mathematicsComputer sciencebusiness.industryLatent semantic analysisInformationSystems_INFORMATIONSTORAGEANDRETRIEVALRepresentation (systemics)computer.software_genreChatbotGeometric algebraKnowledge baseArtificial IntelligenceEncoding (semiotics)chatbot clifford algebraArtificial intelligenceDialog systembusinesscomputerNatural language processingNatural language
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Random Stability of an Additive-Quadratic-Quartic Functional Equation

2010

Using the fixed point method, we prove the generalized Hyers-Ulam stability of the following additive-quadratic-quartic functional equation f(x+2y)+f(x−2y)=2f(x+y)+2f(−x−y)+2f(x−y)+2f(y−x)−4f(−x)−2f(x)+f(2y)+f(−2y)−4f(y)−4f(−y) in complete random normed spaces.

Settore MAT/05 - Analisi MatematicaApplied Mathematicslcsh:MathematicsDiscrete Mathematics and Combinatoricslcsh:QA1-939AnalysisRandom normed space fixed point generalized Hyers-Ulam stability additive-quadratic-quartic functional equationJournal of Inequalities and Applications
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Denjoy and P-path integrals on compact groups in an inversion formula for multiplicative transforms

2009

Abstract Denjoy and P-path Kurzweil-Henstock type integrals are defined on compact subsets of some locally compact zero-dimensional abelian groups. Those integrals are applied to obtain an inversion formula for the multiplicative integral transform.

Settore MAT/05 - Analisi MatematicaGeneral MathematicsPath integral formulationMultiplicative functionMathematical analysisLocally compact spaceDenjoy integral multiplicative transformsAbelian groupLocally compact groupIntegral transformInversion (discrete mathematics)MathematicsVolume integral
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Discrete Time Portfolio Selection with Lévy Processes

2007

This paper analyzes discrete time portfolio selection models with Lévy processes. We first implement portfolio models under the hypotheses the vector of log-returns follow or a multivariate Variance Gamma model or a Multivariate Normal Inverse Gaussian model or a Brownian Motion. In particular, we propose an ex-ante and an ex-post empirical comparisons by the point of view of different investors. Thus, we compare portfolio strategies considering different term structure scenarios and different distributional assumptions when unlimited short sales are allowed.

Settore SECS-S/06 - Metodi mat. dell'economia e Scienze Attuariali e Finanziarieterm structureexpected utilitySubordinated Lévy models; term structure; expected utility; portfolio strategiesportfolio strategiesMultivariate normal distributionSubordinated Lévy modelsVariance-gamma distributionInverse Gaussian distributionsymbols.namesakeSettore SECS-S/06 -Metodi Mat. dell'Economia e d. Scienze Attuariali e Finanz.Discrete time and continuous timesymbolsEconometricsPortfolioSubordinated Lévy models term structure expected utility portfolio strategiesPost-modern portfolio theoryPortfolio optimizationModern portfolio theoryMathematics
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