Search results for " parametric"

Bayesian classification for dating archaeological sites via projectile points

2021

Dating is a key element for archaeologists. We propose a Bayesian approach to provide chronology to sites that have neither radiocarbon dating nor clear stratigraphy and whose only information comes from lithic arrowheads. This classifier is based on the Dirichlet-multinomial inferential process and posterior predictive distributions. The procedure is applied to predict the period of a set of undated sites located in the east of the Iberian Peninsula during the IVth and IIIrd millennium cal. BC.

Spatial Simultons in 2D Photonic Crystals of Nonlinear Origin

2007

We observed for the very first time quadratic spatial solitons (simultons) in a two dimensional photonic lattice defined by periodic sign inversion of its susceptibilty. This is the first demonstration of quadratic self-confinement in a 2D purely nonlinear photonic crystal.

Supercontinuum Generation in Tellurite Optical Fibers

2017

This chapter presents a state of the art of infrared supercontinuum generation in heavy oxide tellurite optical fibers from the experimental results published by the international community. As a first part, a bibliographic table gathers the literature on which this work is based. Then, the second part briefly returns on the tellurite glass compositions, the third part presents the different fiber structures (microstructured, suspended core or step-index fibers, tapered fibers), the fourth part discusses the pumping sources in relation with the fiber chromatic dispersion as well as coupling issues, the supercontinuum performances are presented in the fifth part, and the sixth part deals wit…

Constructal law optimization of a boiler

2017

The paper aims at the optimization of the design of a biomass boiler under the inspiration of the Constructal Law by Bejan. The boiler is of the smoke tubes typology, fuel being biomass pellets. The smoke tubes are 16 and are placed in a staggered configuration. A model is built in MATLAB environment, based on empirical correlations and the mean log temperature methodology. The analysis is based on the development of a wide parametric analysis that involves variations of diameters, numbers and positioning of the tubes. Results are based on the concept of the overall performance coefficient methodology and investigate both the pressure drops variation and the thermal power generated in the d…

Multiplicative cases from additive cases: Extension of Kolmogorov–Feller equation to parametric Poisson white noise processes

2007

Abstract In this paper the response of nonlinear systems driven by parametric Poissonian white noise is examined. As is well known, the response sample function or the response statistics of a system driven by external white noise processes is completely defined. Starting from the system driven by external white noise processes, when an invertible nonlinear transformation is applied, the transformed system in the new state variable is driven by a parametric type excitation. So this latter artificial system may be used as a tool to find out the proper solution to solve systems driven by parametric white noises. In fact, solving this new system, being the nonlinear transformation invertible, …

Il “Generative Design” nel progetto dell’involucro architettonico: Un modello applicativo

2008

Bayesian correlated models for assessing the prevalence of viruses in organic and non-organic agroecosystems

2017

Cultivation of horticultural species under organic management has increased in importance in recent years. However, the sustainability of this new production method needs to be supported by scientific research, especially in the field of virology. We studied the prevalence of three important virus diseases in agroecosystems with regard to its management system: organic versus non-organic, with and without greenhouse. Prevalence was assessed by means of a Bayesian correlated binary model which connects the risk of infection of each virus within the same plot and was defined in terms of a logit generalized linear mixed model (GLMM). Model robustness was checked through a sensitivity analysis …

Frequency Domain Information Decomposition: Application to Plateau Waves of Intracranial Pressure

2022

The sustainment and/or resurgence of Plateau Waves (PWs) reveals a borderline cerebral situation of the pressure-volume relationship and is related to increased mortality. The intense systemic stress caused by PWs can be evidenced by the study of Heart Rate Variability (HRV), which is an indicator of the activity of the autonomic nervous system, namely the sympathetic and parasympathetic imbalance. In this work, heart and brain crosstalk interactions will be analyzed using a spectral decomposition of multivariate information measures, which provides frequency-specific quantification of the information shared between a target and two source time series. The spectral measures of information h…

Objective Bayesian point and region estimation in location-scale models.

2007

Point and region estimation may both be described as specific decision problems. In point estimation, the action space is the set of possible values of the quantity on interest; in region estimation, the action space is the set of its possible credible regions. Foundations dictate that the solution to these decision problems must depend on both the utility function and the prior distribution. Estimators intended for general use should surely be invariant under one-to-one transformations, and this requires the use of an invariant loss function; moreover, an objective solution requires the use of a prior which does not introduce subjective elements. The combined use of an invariant informatio…

Prediction Equations for Out-of-Plane Capacity of Unreinforced Masonry Infill Walls Based on a Macroelement Model Parametric Analysis

2021

In the seismic performance assessment of reinforced concrete (RC) frames, a reliable estimation of the capacity of unreinforced masonry (URM) infill walls is of utmost importance to ensure structural safety conditions. With particular attention to the out- of-plane (OoP) capacity of URM infill walls after in-plane (IP) damage, the issue of defining reliable analytical prediction models for the assessment of the capacity is an ongoing study. In this paper, empirical equations are proposed for the evaluation of the infilled frame’s OoP capacity, with or without IP damage, based on an extensive numerical parametric analysis, focusing on the influence of the key parameters that govern the mecha…