Search results for "Proof"

Code Interoperability and Standard Data Formats in Quantum Chemistry and Quantum Dynamics: The Q5/Q5cost Data Model

2014

Code interoperability and the search for domain-specific standard data formats represent critical issues in many areas of computational science. The advent of novel computing infrastructures such as computational grids and clouds make these issues even more urgent. The design and implementation of a common data format for quantum chemistry (QC) and quantum dynamics (QD) computer programs is discussed with reference to the research performed in the course of two Collaboration in Science and Technology Actions. The specific data models adopted, Q5Cost and D5Cost, are shown to work for a number of interoperating codes, regardless of the type and amount of information (small or large datasets) …

Epistemic and didactic values of the demonstrative process in different cultures: a case study in Geometry with Chinese and Italian students

2011

Lead Poisoning in France around 1840: Managing Proofs and Uncertainties in Laboratories, Courtrooms, and Workplaces.

2021

This article reviews one of the most famous cases of lead poisoning in France, the Ponchon affair, which occurred in 1843 during a crucial period for French toxicology. The trial attracted public attention and inflamed controversy among medical and legal experts. The debate involved toxicological methods and their reliability, and gave rise to more general questions about the value of expert evidence, the way it was presented in court, and its relationship to other forms of legal evidence. I begin with a general overview of lead poisoning and toxicological research on lead compounds around 1840. I then discuss different toxicological proofs employed for detecting or preventing lead poisonin…

Assessment of protection treatments for carbonatic stone using nanocomposite coatings

2020

In this paper the effect of the application of four kinds of polymer dispersions containing nanoparticles, used as protectives, on two type of carbonatic lithotypes, White Noto and Comiso stone, is reported. The study was conducted by analysing the contribution of each component of the system. After the structural characterization of the coating itself, the performance of those colloidal systems has been studied upon application on the calcarenites, preferring non-invasive techniques and microdestructive techniques. Effect of the nanoparticles presence on hydrorepellency and roughness of the stone surface and on chromatic changes has also been considered. The tests conducted have proven tha…

Lo sviluppo economico è/e lo sviluppo della qualità: un parco dell'innovazione a Catania

2022

Il tema delle periferie produttive (o ex produttive) negli ultimi anni ha assunto un ruolo predominante nella pianificazione delle città al fine di rivalutare le aree industriali dismesse come serbatoi per la riqualificazione urbana ed economica delle nostre città. Sicurezza, degrado sociale e ambientale, abbandono, consumo di suolo sono le principali problematiche di queste aree e investire nella loro riqualificazione può essere un’occasione centrale per la “ripartenza” economica delle nostre città. Per tale motivo, la Regione Siciliana ha recentemente designato una vasta area della città di Catania come “Zona Economica Speciale” (ZES) per il rilancio delle filiere economiche della città. …

Pulse doubling and wavelength conversion through triangular nonlinear pulse reshaping

2011

International audience; We present a proof of principle experiment demonstrating the benefits of using a triangular temporal profile in the context of copying and wavelength conversion of telecommunication signals. Generated by passive nonlinear reshaping in a set of two carefully chosen fibres, the triangular shape enables efficient temporal and spectral doubling of the signals through self-phase modulation.

Modular Assembly of Multimodal Imaging Agents through an Inverse Electron Demand Diels–Alder Reaction

2019

International audience; The combination of two imaging probes on a same biomolecule gives access to targeted bimodal imaging agents that can provide more accurate diagnosis, complementary information, or that may be used in different applications, such as PET imaging and fluorescence imagingassisted surgery. In this study, we demonstrate that dichlorotetrazine, a small, commercially available compound, can be used as a modular platform to easily assemble various imaging probes. Doubly-labeled tetrazines can then be conjugated to a protein through a biorthogonal IEDDA reaction. A series of difunctionalized tetrazine compounds containing various chelating agents and fluorescent dyes was synth…

A Study of Students' Reasoning About “There exists no ...”

2018

International audience; In this paper, we report findings from two studies of students' engagement in metatheoretical tasks drawn from a model of the reasoning requirements of a proof by contradiction. The studies explored students' engagement in and success with the tasks, as well as the similarities and differences in students' and mathematicians' approaches. Findings indicate students tended towards syntactic, logical theory approaches while mathematicians gravitate towards semantic, mathematical theory approaches. Drawing on interview data, it is shown that students may use symbols to avoid employing fragile content knowledge, yet encounter further difficulties by viewing quantifiers as…

Nonlinear Feedback Control and Stability Analysis of a Proof-of-Work Blockchain

2017

In this paper a novel feedback controller and stability analysis of a blockchain implementation is developed by using a control engineering perspective. The controller output equals the difficulty adjustment in the mining process while the feedback variable is the average block time over a certain time period. The computational power (hash rate) of the miners is considered a disturbance in the model. The developed controller is tested against a simulation model with constant disturbance, step and ramp responses as well as with a high-frequency sinusoidal disturbance. Stability and a fast response is demonstrated in all these cases with a controller which adjusts it's output at every new blo…

Scalable Electro-Optic Control of Localized Bistable Switching in Broad-Area VCSELs Using Reconfigurable Funnel Waveguides

2017

We demonstrate a steplike optical modulation based on the activation and deactivation of a bistable localized structure using a photoinduced and reconfigurable miniaturized 30 × 30 μm electroactivated funnel waveguide. Control of a single 10-μm-diameter spot in a 200-μm-diameter vertical-cavity surfaceemitting laser at 980 nm is achieved modulating the phase of an exciting beam in the specific position of the spot in the cavity. This localized on-off response can be scaled into arrays and offer a possible route to fast integrated optical logical functions and memory at low intensities at near-infrared wavelengths.