Search results for " Probability"

showing 10 items of 2176 documents

Analytical representation of bimodality in bivariate distribution of chain length and chemical composition of copolymers

2022

Abstract Tuning the bimodality of microstructural features in polymers has provided novel properties and applications. A classic example is to overcome the trade-off between processability and mechanical properties in polyolefins. A recent example is to decrease the interfacial tension in blending incompatible polymers. Therefore, the development of a bimodality index (BI), especially for the chain length distribution (CLD) and the chemical composition distribution (CCD), is crucial for the quantitative design of materials. This study introduces quantitative expressions for the bimodality of univariate CLD on the linear scale, and CCD. Moreover, we develop a bimodality criterion for bivaria…

Series (mathematics)General Chemical EngineeringUnivariateGeneral ChemistryBivariate analysisIndustrial and Manufacturing EngineeringBimodalityDistribution (mathematics)Joint probability distributionLinear scaleEnvironmental ChemistryStatistical physicsRepresentation (mathematics)MathematicsChemical Engineering Journal
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On estimating contemporaneous quarterly regional GDP

2007

Subnational regional jurisdictions rarely have at their disposal a reasonable array of timely statistics to monitor their economic condition. In light of this, we develop a procedure that simultaneously estimates a quarterly time series for all regions of a country based upon quarterly national and annual regional data. While other such techniques exist, we suggest a temporal error structure that eliminates possible spurious jumps. Using our approach, regional analysts should now be able to distribute national growth among regions as soon as quarterly national figures are released. In a Spanish application, we detail some practicalities of the process and show that our proposal produces bet…

Series (mathematics)Process (engineering)Strategy and ManagementModeling and SimulationEconometricsEconomicsManagement Science and Operations ResearchStatistics Probability and UncertaintyTime seriesSpurious relationshipComputer Science ApplicationsJournal of Forecasting
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Universal freezing of quantum correlations within the geometric approach

2015

Quantum correlations in a composite system can be measured by resorting to a geometric approach, according to which the distance from the state of the system to a suitable set of classically correlated states is considered. Here we show that all distance functions, which respect natural assumptions of invariance under transposition, convexity, and contractivity under quantum channels, give rise to geometric quantifiers of quantum correlations which exhibit the peculiar freezing phenomenon, i.e., remain constant during the evolution of a paradigmatic class of states of two qubits each independently interacting with a non-dissipative decohering environment. Our results demonstrate from first …

Settore FIS/02 - Fisica Teorica Modelli E Metodi MatematiciFOS: Physical sciencesQuantum entanglementArticleConvexityInformation theory and computation Qubits Quantum information Open quantum systems quantum correlationsStatistical physicsQAQuantumQCCondensed Matter - Statistical MechanicsMathematical PhysicsPhysicsQuantum PhysicsMultidisciplinaryStatistical Mechanics (cond-mat.stat-mech)Probability and statisticsState (functional analysis)Mathematical Physics (math-ph)Quantum technologyPhysics - Data Analysis Statistics and ProbabilityQubitConstant (mathematics)Quantum Physics (quant-ph)Data Analysis Statistics and Probability (physics.data-an)
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Proceedings of MDP2007 international Symposium on Recent Advances in Mechanics (structural/solid) Dynamical Systems (deterministic/stochastic) Probab…

2009

Settore ICAR/08 - Scienza Delle Costruzionimechanics Structural dynamics probability theory
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Evolved factor method for service life prediction of building components

2013

Key issues in the production process associated with construction are the implementation of quality and sustainability principles. Indeed, it is increasingly important in the maintenance of quality levels provided by materials, components and building structures, especially after the recent Regulation (EU) No. 305/2011. This document introduced the seventh requirement for the sustainable use of natural resources, guaranteeing the durability of construction products, thus being planned. The international standard for the assessment of durability of building materials and components is the ISO 15686 - Buildings and constructed assets - Service life planning, providing the definition of the Re…

Settore ICAR/11 - Produzione EdiliziaFactor method durability service life log-normal function probability distribution function
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Rateless Codes Performance Analysis in Correlated Channel Model for GEO Free Space Optics Downlinks

2012

Settore ING-INF/03 - TelecomunicazioniFree Space Optics (FSO) technologies for satellite communications offer several advantages: wide bandwidth high rate capability immunity to electromagnetic interference and small equipment size. Thus they are suitable for inter-satellite links deep space communications and also for high data rate ground-to-satellite/satellite-to-ground communications. Nevertheless FSO links suffer impairments that cause power signal degradation at the receiver. Scattering and absorption cause power signal attenuations predictable by suitable deterministic models. Optical turbulence causes random irradiance fluctuations which can generate signal fading events and can thereby only be predicted by statistical models. Attenuation and fading events can corrupt FSO links and so it would be recommended to add mitigation error codes on the communication link. FSO channel can be described as an erasure channel: fading events can cause erasure errors. We have identified in rateless codes (RCs) a suitable solution to be employed in FSO links. RCs do not need feedback and they add a redundant coding on the source data that allows the receiver to recover the whole payload despite erasure errors. We implemented two different of rateless codes: Luby Transform (LT) and Raptor. We analyzed their performances on a simulated turbulent GEO FSO downlink (1 Gbps - OOK modulation) at a 106 μm wavelength and for different values of zenith angles. Assuming a plane-wave propagation and employing Hufnagel-Valley we modeled the downlink using: 1) a temporal correlated channel model based on Gamma-Gamma probability distribution and 2) an irradiance covariance function that we converted on a time function using Taylor frozen eddies hypothesis. Our new channel model is able to simulate irradiance fluctuations at different turbulence conditions as it will be shown in the full paper. We will also report performance results of LT and Raptor codes at overhead range varying between 0 and 50% and for different values of source packets.Settore ING-INF/01 - Elettronica
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Design of an Adaptive Bayesian System for Sensor Data Fusion

2014

Many artificial intelligent systems exploit a wide set of sensor devices to monitor the environment. When the sensors employed are low-cost, off-the-shelf devices, such as Wireless Sensor Networks (WSN), the data gathered through the sensory infrastructure may be affected by noise, and thus only partially correlated to the phenomenon of interest. One way of overcoming these limitations might be to adopt a high-level method to perform multi-sensor data fusion. Bayesian Networks (BNs) represent a suitable tool for performing refined artificial reasoning on heterogeneous sensory data, and for dealing with the intrinsic uncertainty of such data. However, the configuration of the sensory infrast…

Settore ING-INF/05 - Sistemi Di Elaborazione Delle InformazioniAmbient IntelligencePervasive SystemsComputer scienceDistributed computingSensor nodeBayesian probabilityBayesian networkInferenceNoise (video)Sensor fusionWireless sensor network
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TSVD as a Statistical Estimator in the Latent Semantic Analysis Paradigm

2015

The aim of this paper is to present a new point of view that makes it possible to give a statistical interpretation of the traditional latent semantic analysis (LSA) paradigm based on the truncated singular value decomposition (TSVD) technique. We show how the TSVD can be interpreted as a statistical estimator derived from the LSA co-occurrence relationship matrix by mapping probability distributions on Riemanian manifolds. Besides, the quality of the estimator model can be expressed by introducing a figure of merit arising from the Solomonoff approach. This figure of merit takes into account both the adherence to the sample data and the simplicity of the model. In our model, the simplicity…

Settore ING-INF/05 - Sistemi Di Elaborazione Delle InformazioniHellinger DistanceLatent semantic analysisComputer sciencebusiness.industryProbabilistic logicEstimatorStatistical modelPattern recognitionComputer Science ApplicationsHuman-Computer Interactiondata-driven modelingData models Semantics Probability distribution Matrix decomposition Computational modeling Probabilistic logicLSASingular value decompositionComputer Science (miscellaneous)Probability distributionTruncation (statistics)Artificial intelligenceHellinger distancebusinessAlgorithmInformation SystemsIEEE Transactions on Emerging Topics in Computing
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Does More Context Help? Effects of Context Window and Application Source on Retrieval Performance

2021

We study the effect of contextual information obtained from a user’s digital trace on Web search performance. Contextual information is modeled using Dirichlet–Hawkes processes (DHP) and used in augmenting Web search queries. The context is captured by monitoring all naturally occurring user behavior using continuous 24/7 recordings of the screen and associating the context with the queries issued by the users. We report a field study in which 13 participants installed a screen recording and digital activity monitoring system on their laptops for 14 days, resulting in data on all Web search queries and the associated context data. A query augmentation (QAug) model was built to expand the or…

Settore ING-INF/05 - Sistemi Di Elaborazione Delle InformazioniInformation retrievalContext windowSettore INF/01 - InformaticaComputer science05 social sciencesContext (language use)01 natural sciencesGeneral Business Management and AccountingComputer Science ApplicationsTrace (semiology)010104 statistics & probabilitydigital user behavior contextual information context window query augmentation application source Web searchContextual information0509 other social sciences0101 mathematics050904 information & library sciencesInformation Systems
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Composite laminates buckling optimization through Levy based Ant Colony Optimization

2010

In this paper, the authors propose the use of the Levy probability distribution as leading mechanism for solutions differentiation in an efficient and bio-inspired optimization algorithm, ant colony optimization in continuous domains, ACOR. In the classical ACOR, new solutions are constructed starting from one solution, selected from an archive, where Gaussian distribution is used for parameter diversification. In the proposed approach, the Levy probability distributions are properly introduced in the solution construction step, in order to couple the ACOR algorithm with the exploration properties of the Levy distribution. The proposed approach has been tested on mathematical test functions…

Settore ING-INF/05 - Sistemi Di Elaborazione Delle InformazioniMathematical optimizationComputer scienceGaussianAnt colony optimization algorithmsLévy distributionMaximizationFunction (mathematics)Composite laminatessymbols.namesakeDistribution (mathematics)symbolsProbability distributionSettore ICAR/08 - Scienza Delle CostruzioniLevy probability distribution Ant colony optimization composite laminates buckling load maximization
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