Search results for "Dynamic"

Realization of time-resolved two-vacuum-ultraviolet-photon ionization

2009

International audience; Ultrafast dynamics of excited molecules is studied through time-resolved two-vacuum-ultraviolet (vuv)- photon ionization using a nonlinear volume autocorrelator unit. The two-vuv-photon process is induced by the intense fifth harmonic radiation of a femtosecond Ti:sapphire laser. In a proof-of-principle experiment, ultrafast dynamics of excited ethylene and oxygen molecules are investigated. Molecular decay times are deduced by comparing the experimental data with the results of a numerical model that accounts for the spatial and temporal characteristics of the harmonic field. The present experiments pave a convenient way for time domain investigations in the vuv-xuv s…

Spectroscopic studies of semiconducting single-walled carbon nanotubes

2010

The unique nature of optical properties of single-walled carbon nanotubes (SWCNT), together with their promising potential applications, have created enormous interest towards the photophysics of SWCNT. Many aspects of carbon nanotubes originate from the electronic structure of carbon honeycomb lattice and one-dimensionality. SWCNTs exist in various chiral structures and diameters, which the optical and electrical properties are dependent on. It has been discovered that SWCNT excited states are excitonic with strong Coulomb interaction between the electron and the hole. However, many features of excitons are not yet well defined, such as absorption cross-sections, fluorescence quantum yield…

Cooperative spectrum sensing schemes for future dynamic spectrum access infrastructures

2016

Ski jumping takeoff in a wind tunnel with skis.

2011

The effect of skis on the force–time characteristics of the simulated ski jumping takeoff was examined in a wind tunnel. Takeoff forces were recorded with a force plate installed under the tunnel floor. Signals from the front and rear parts of the force plate were collected separately to examine the anteroposterior balance of the jumpers during the takeoff. Two ski jumpers performed simulated takeoffs, first without skis in nonwind conditions and in various wind conditions. Thereafter, the same experiments were repeated with skis. The jumpers were able to perform very natural takeoff actions (similar to the actual takeoff) with skis in wind tunnel. According to the subjective feeling of the…

Il dynamic business model: una prospettiva dinamica per la progettazione dei modelli di business

2017

Building on the extant literature on business modelling and focussing on start-up firms, this article aims at exploring the combination between conventional business model schemes and System Dynamics methodology with the intent to overcome those limitations related to a static design approach. By mapping the multiple key elements underlying value creation processes – linked according to a cause-and-effect perspective – and with the support of a simulation-based methodology, entrepreneurs may experiment and understand how the firm reacts to strategic and organizational changes in terms of performance, innovation and value creation.

Modeling and Backstepping Control of the Electronic Throttle System

2013

Published version of an article in the journal: Mathematical Problems in Engineering. Also available from the publisher at: http://dx.doi.org/10.1155/2013/871674 Open access Electronic throttle is widely used in modern automotive engines. An electronic throttle system regulates the throttle plate angle by using a DC servo motor to adjust the inlet airflow rate of an internal combustion engine. Its application leads to improvements in vehicle drivability, fuel economy, and emissions. In this paper, by taking into account the dynamical behavior of the electronic throttle, the mechanism model is first built, and then the mechanism model is transformed into the state-space model. Based on the s…

Inferring directionality of coupled dynamical systems using Gaussian process priors: Application on neurovascular systems

2022

Dynamical system theory has recently shown promise for uncovering causality and directionality in complex systems, particularly using the method of convergent cross mapping (CCM). In spite of its success in the literature, the presence of process noise raises concern about CCM's ability to uncover coupling direction. Furthermore, CCM's capacity to detect indirect causal links may be challenged in simulated unidrectionally coupled Rossler-Lorenz systems. To overcome these limitations, we propose a method that places a Gaussian process prior on a cross mapping function (named GP-CCM) to impose constraints on local state space neighborhood comparisons. Bayesian posterior likelihood and…

Mathematical Methods for Research Excellence : Book of Abstracts

2022

Treatment of oral lichen planus with photodynamic therapy mediated methylene blue: a case report.

2006

Oral lichen planus (OLP) is a common chronic disease of uncertain origin. Many patients with OLP are refractory to all available therapies. The photodynamic therapy (PDT) was used as a possible alternative method in the treatment of lichen planus. Two patients with five oral lichen planus lesions were treated using topical PDT mediated by methylene blue (MB-PDT). The patients were followed up on sessions 3, 7, 15 days and 1 to 9 months after PDT. Clinical improvement was achieved in four lesions. Two lesions showed complete remission, and another two lesions had about 50% clinically improvement 3-9 months after a single session of PDT. No response detected in one lesion. MB-PDT blue seems t…

Influence of the Resin Layer Thickness at the Interface of Hybrid Metal-composite Co-cured Joints

2011

As discussed in literature, the accurate analysis of the modern co-cured joints between composite materials or between a metal and a composite material (hybrid joints) is complicated by the influence of the interface resin layer on the interface singular stress field. In such joints, in fact, there is not a proper adhesive layer and the thickness of the resin layer, that plays the role of the adhesive, is not constant due to the presence of the reinforcing fibers in the composite adherent. For this reason several authors assume that a generic co-cured joint can not be studied as a simple bi-material joint, without considering the particular characteristics of the actual resin layer. This pr…