Search results for "Turing"
showing 10 items of 2644 documents
Energy and environmental assessment of residual bio-wastes management strategies
2021
Abstract This paper assesses the potential energy and environmental impacts of an anaerobic digester coupled with a combined heat and power plant powered with bio-wastes from the agri-food sector. The analysis is carried out through the Life Cycle Assessment methodology following a “cradle-to-grave” approach and is based mostly on primary data. The anaerobic digester - combined heat and power plant is analysed considering a twofold perspective: one more energy – oriented where the main function of the system is to generate renewable electricity and a waste – oriented one in which the main function is treating bio-wastes. In addition, the environmental indirect effects related to potential c…
The role of water in the impact of high pressure on the myrosinase activity and glucosinolate content in seedlings from Brussels sprouts
2019
Abstract In this study, it was shown that the amount of available water was found to influence the high pressure processing (HPP) effect on both myrosinase activity and total glucosinolate concentration in Brussels sprouts seedlings. Brussels sprouts seedlings with different water content (wc = 4.8–89.4%) and water activity (aw = 0.17–0.97) were pressurized at selected pressures between 200 and 800 MPa (5 °C and 3 min), thereby affecting pressure-induced enzyme denaturation, molecular diffusion, and cell permeability differently. The myrosinase activity and intact glucosinolate content in the dry seedlings (wc Industrial relevance High pressure processing (HPP) is increasingly applied in t…
Obtaining and Characterisation of Starch-Based Edible Films Incorporating Honey, Propolis and Bee Bread
2019
Abstract This research investigates the physical-chemical, sensorial and mechanical characteristics of starch-based edible films incorporating three types of bee hive products: honey, propolis and bee bread, in concentrations varying from 1% to 3%, reported to starch. The results indicates an increasing of films moisture, water activity, ash content and acidity, in the order: honey<propolis<bee bread, all values increasing with the increasing of hive products percentage into the control film; aw is remaining at very low values, under 0.4. Sensorial analysis indicated honey as the better suited for improving taste and flavour and bee bread for increasing colour intensity of the films; …
Numerical simulation of wave energy production through experimental tool
2017
Wave energy is highly desirable resource and recent international reports underline its major relevance on global renewable energy in future. In general, the first step is a correct WEC (Wave Energy Converter) sizing and design. The aim of this paper is a presentation of an application of one experimental tool to define the external floating structure of WEC realized by University of Palermo. This new electric device could be another energy possibility for small islands in the Mediterranean Sea as Pantelleria, Lampedusa or Malta.
Ultrathin high-index metasurfaces for shaping focused beams
2015
The volume size of a converging wave, which plays a relevant role in image resolution, is governed by the wavelength of the radiation and the numerical aperture (NA) of the wavefront. We designed an ultrathin (λ/8 width) curved metasurface that is able to transform a focused field into a high-NA optical architecture, thus boosting the transverse and (mainly) on-axis resolution. The elements of the metasurface are metal-insulator subwavelength gratings exhibiting extreme anisotropy with ultrahigh index of refraction for TM polarization. Our results can be applied to nanolithography and optical microscopy. Spanish Ministry of Economy and Competitiveness (MEC) (TEC2013-50416-EXP).
Physical compensation of phase curvature in digital holographic microscopy by use of programmable liquid lens.
2015
Quantitative phase measurements obtained with digital holographic microscopes are strongly dependent on the optical arrangement of the imaging system. The nontelecentric operation provides phase measurements affected by a parabolic phase factor and requires numerical postprocessing, which does not always remove all the perturbation. Accurate phase measurements are achieved by using the imaging system in telecentric mode. Unfortunately, this condition is not accomplished when a commercial microscope is used as the imaging system. In this paper, we present an approach for obtaining accurate phase measurements in nontelecentric imaging systems without the need for numerical postprocessing. The…
Spatial light modulator phase mask implementation of wavefront encoded 3D computational-optical microscopy
2015
Spatial light modulator (SLM) implementation of wavefront encoding enables various types of engineered pointspread functions (PSFs), including the generalized-cubic and squared-cubic phase mask wavefront encoded (WFE) PSFs, shown to reduce the impact of sample-induced spherical aberration in fluorescence microscopy. This investigation validates dynamic experimental parameter variation of these WFE-PSFs. We find that particular design parameter bounds exist, within which the divergence of computed and experimental WFE-PSFs is of the same order of magnitude as that of computed and experimental conventional PSFs, such that model-based approaches for solving the inverse imaging problem can be a…
Experimental validation of a customized phase mask designed to enable efficient computational optical sectioning microscopy through wavefront encodin…
2017
In this paper, wavefront-encoded (WFE) computational optical sectioning microscopy (COSM) using a fabricated square cubic (SQUBIC) phase mask, designed to render the system less sensitive to depth-induced aberration, is investigated. The WFE-COSM system is characterized by a point spread function (PSF) that does not vary as rapidly with imaging depth compared to the conventional system. Thus, in WFE-COSM, image restoration from large volumes can be achieved using computationally efficient space-invariant (SI) algorithms, thereby avoiding the use of depth-variant algorithms. The fabricated SQUBIC phase mask was first evaluated and found to have a 75% fidelity compared to the theoretical desi…
Weakly nonlinear analysis of Turing patterns in a morphochemical model for metal growth
2015
We focus on the morphochemical reaction–diffusion model introduced in Bozzini et al. (2013) and carry out a nonlinear bifurcation analysis with the aim to characterize the shape and the amplitude of the patterns arising as the result of Turing instability of the physically relevant equilibrium. We perform a weakly nonlinear multiple scales analysis, and derive the normal form equations governing the amplitude of the patterns. These amplitude equations allow us to construct relevant solutions of the model equations and reveal the presence of multiple branches of stable solutions arising as the result of subcritical bifurcations. Hysteretic type phenomena are highlighted also through numerica…
Cross-Diffusion Driven Instability in a Predator-Prey System with Cross-Diffusion
2013
In this work we investigate the process of pattern formation induced by nonlinear diffusion in a reaction-diffusion system with Lotka-Volterra predator-prey kinetics. We show that the cross-diffusion term is responsible of the destabilizing mechanism that leads to the emergence of spatial patterns. Near marginal stability we perform a weakly nonlinear analysis to predict the amplitude and the form of the pattern, deriving the Stuart-Landau amplitude equations. Moreover, in a large portion of the subcritical zone, numerical simulations show the emergence of oscillating patterns, which cannot be predicted by the weakly nonlinear analysis. Finally when the pattern invades the domain as a trave…