Search results for "TRANSFORMATION"
showing 10 items of 1634 documents
Relations between multi-resolution analysis and quantum mechanics
2005
We discuss a procedure to construct multiresolution analyses (MRA) of L2 (R) starting from a given seed function h (s) which should satisfy some conditions. Our method, originally related to the quantum mechanical Hamiltonian of the fractional quantum Hall effect, is shown to be model independent. The role of a canonical map between certain canonically conjugate operators is discussed. This clarifies our previous procedure and makes much easier most of the original formulas, producing a convenient framework to produce examples of MRA. © 2005 American Institute of Physics.
La cultura ci salverà? Processi di touristification a base culturale nel centro storico di Palermo
2023
Negli ultimi tre decenni la cultura ha avuto un ruolo chiave nella costruzione delle politiche urbane, divenendo uno strumento decisivo nella definizione delle strategie di sviluppo economico e nell’accesso alla competizione globale che caratterizzano l’attuale regime di neoliberismo urbano (Miles e Paddison 2005). Anche nel sud Europa la cosiddetta rigenerazione a base culturale ha rappresentato e continua ancora oggi a rappresentare una vera e propria ortodossia urbana, che trova nel turismo tanto una ragione di esistenza quanto un campo di attuazione. In particolare, negli ultimi anni i centri storici di molte città sudeuropee sono stati oggetto di trasformazioni profonde in cui pratiche…
Zero-Dimensional Hybrid Organic−Inorganic Lead Halides and Their Post-Synthesis Reversible Transformation into Three-Dimensional Perovskites
2021
Zero-dimensional (0D) mixed-halide hybrid organic-inorganic MA4PbX6·2H2O (MA = CH3NH3+; X = Br1 - xIx with 0 < x < 1) has been synthesized by a solvent-free mechanochemical approach. It has been shown that this 0D phase with sharp absorption features in the near-UV is a hydrated structure, which can be reversibly transformed into the three-dimensional perovskite phase MAPbX3 by simple thermal annealing (dehydration) in air. This work reveals a new approach to hybrid organic-inorganic perovskites and related 0D structures, which have so far only been thoroughly studied for the inorganic Cs4PbX6 compounds. Hetero-structures for Efficient Luminescent Devices (HELD) REFERENCIA: 834431 PCIN-2019…
Theoretical efficiency limits for thermoradiative energy conversion
2015
Published version of an article in the journal: Journal of Applied Physics. Also available from the publisher at: http://dx.doi.org/10.1063/1.4907392 A new method to produce electricity from heat called thermoradiative energy conversion is analyzed. The method is based on sustaining a difference in the chemical potential for electron populations above and below an energy gap and let this difference drive a current through an electric circuit. The difference in chemical potential originates from an imbalance in the excitation and de-excitation of electrons across the energy gap. The method has similarities to thermophotovoltaics and conventional photovoltaics. While photovoltaic cells absorb…
Study of thermomagnetic energy conversion driven by renewable energy
2017
Magnetic heating, refrigeration and energy conversion have been defined very important challenges for promising environmentally future choices. Recent studies are focused attention on new thermomagnetic systems, devices working through thermomagnetic effect, driven by renewable energies. The aim of this work is a case study presentation of new thermomagnetic energy prototype coupled with renewable technologies or industrial waste heat. The paper is divided into four sections: the first gives a general state of art about magneto-caloric energy conversion systems, the second describes all general thermodynamics and magnetic laws governing the process, the third and fourth sections study in mo…
Estimating the temperature evolution of foodstuffs during freezing with a 3D meshless numerical method
2015
Abstract Freezing processes are characterised by sharp changes in specific heat capacity and thermal conductivity for temperatures close to the freezing point. This leads to strong nonlinearities in the governing PDE that may be difficult to resolve using traditional numerical methods. In this work we present a meshless numerical method, based on a local Hermite radial basis function collocation approach in finite differencing mode, to allow the solution of freezing problems. By introducing a Kirchhoff transformation and solving the governing equations in Kirchhoff space, the strength of nonlinearity is reduced while preserving the structure of the heat equation. In combination with the hig…
Heat to electricity conversion by cold carrier emissive energy harvesters
2015
This paper suggests a method to convert heat to electricity by the use of devices called cold carrier emissive energy harvesters (cold carrier EEHs). The working principle of such converters is explained and theoretical power densities and efficiencies are calculated for ideal devices. Cold carrier EEHs are based on the same device structure as hot carrier solar cells, but works in an opposite way. Whereas a hot carrier solar cell receives net radiation from the sun and converts some of this radiative heat flow into electricity, a cold carrier EEH sustains a net outflux of radiation to the surroundings while converting some of the energy supplied to it into electricity. It is shown that the…
Library for model querying
2012
Query and transformation languages make it easy to work with models, but they are bound to one particular data store. That makes them hard to adopt in projects where data is stored in a different repository, which hinders more widespread use of transformations and models. Instead of adopting a transformation language to a new data store, we propose to build a query and transformation library for the general-purpose language that is already used in a project. In this paper we demonstrate that it can be easily by implementing such a library for an EMOF-like data store in the Lua language.
La grève générale introuvable. France, 1968-1995
2016
International audience; ...
Improved co-oxidation of β-carotene to β-ionone using xanthine oxidase-generated reactive oxygen species in a multiphasic system
2007
beta-Ionone, an aroma compound exhibiting flower notes, can be obtained from beta-carotene in a cooxidation system utilizing xanthine oxidase-generated reactive oxygen species (ROS). ROS have to be controlled as, although they can give rise to beta-ionone, they may also degrade it. In this work, the biotransformation of beta-carotene into beta-ionone was investigated in systems containing variable proportions of decane to extract beta-ionone before degradation. The use of 50% or 90% decane resulted in increased production yields. Tween 80, which was added to further improve the production, slightly decreased the reactivity of the medium and the extraction of beta-carotene, but increased the…