Search results for "LAB"
showing 10 items of 7932 documents
Le statut de l'avocat collaborateur libéral suite aux États généraux de l'avenir de la profession
2019
International audience
Job strain in public transport drivers: Data to assess the relationship between demand-control model indicators, traffic accidents and sanctions
2018
This Data in Brief (DiB) article examines the association between the Job Demand-Control (JDC) model of stress and traffic safety outcomes (accidents and sanctions) in public transport drivers (n = 780). The data was collected using a structured self-administrable questionnaire composed of measurements of work stress (Job Content Questionnaire), and demographics (professional driving experience, hours and days working/driving per week). The data contains 4 parts: descriptive statistics, bivariate correlations between the study variables, analysis of variance (ANOVA) and Post-Hoc comparisons between drivers classified different quadrants of the JDC model. For further information, it is conve…
A Self-Funding Reward Mechanism for Tax Compliance
2015
We compare in a laboratory experiment two audit-based tax compliance mechanisms that collect fines from those found non-compliant. The mechanisms differ in the way fines are redistributed to individuals who were either not audited or audited and found to be compliant. The first, as is the case in most extant tax systems, does not discriminate between the un-audited and those found compliant. The second targets the redistribution in favor of those found compliant. We find that targeting increases compliance when paying taxes generates a social return. We do not find any increase in compliance in a control treatment where individuals audited and found compliant receive symbolic rewards. It is…
Numerical approach to the exact controllability of hyperbolic systems
2005
In this paper we present the numerical implementation of H.U.M. (Hilbert Uniqueness Method, J.L.Lions[1]). We restrict ourselves to the exact boundary controllability of the wave equation, with Dirichlet controls, but the numerical method presented here can be applied to other kinds of controllability. The problem is discretized by a finite elements of first order in space and by a discrete time Galerkin approximation (Dupont [1]). The efficiency of the method is illustrated by numerical results.
Time-harmonic solution for acousto-elastic interaction with controllability and spectral elements
2010
The classical way of solving the time-harmonic linear acousto-elastic wave problem is to discretize the equations with finite elements or finite differences. This approach leads to large-scale indefinite complex-valued linear systems. For these kinds of systems, it is difficult to construct efficient iterative solution methods. That is why we use an alternative approach and solve the time-harmonic problem by controlling the solution of the corresponding time dependent wave equation. In this paper, we use an unsymmetric formulation, where fluid-structure interaction is modeled as a coupling between pressure and displacement. The coupled problem is discretized in space domain with spectral el…
Optimized design of wide-area PSS for damping of inter-area oscillations
2015
In this paper a genetic algorithm based wide area power system stabilizer (PSS) in a multi machine power system for damping of low frequency inter-area oscillations has been presented. The wide area PSS is composed of two stages, the input of one stage is a local signal and the input of other is a global signal. Geometric measure of controllability and observability is used to select the most effective stabilizing signals and location of controller. Tie line active power flow deviation is found to be the most effective input signal. Time domain based objective function is minimized, in which the deviation in the oscillatory rotor speed of generator is involved so that the stability performa…
A boundary controllability approach in optimal shape design problems
2005
We indicate a formulation of optimal shape design problems as boundary control problems, based on some approximate controllability-type results. Numerical examples and a comparison with the standard method are included.
Controllability-type properties for elliptic systems and applications
1991
We consider approximate and exact controllability results for elliptic problems. These results enable one to formulate optimal shape design problems in a fixed domain with certain boundary conditions.
Design and Characterization of a Miniature Hydraulic Power Supply for High-Bandwidth Control of Soft Robotics
2020
Soft robotics holds enormous promise for a wide class of applications. However, system controllability, bandwidth, portability, and energy efficiency of soft robot power supplies are often inadequate. Soft robotics desperately needs improved solutions to drive soft actuators either pneumatically or hydraulically. This research paper offers a contribution to bridge this gap. It deals with small-scale power supplies for hydraulically-driven soft robots based on fluidic elastomer actuators in the power range 5-400 W. A design procedure for such power supplies is developed with an emphasis on high-bandwidth control. The performance requirements are established based on a literature survey, and …
Controllable Solid Rocket Motor Nozzle Operations in Conditions of Limited-Amplitude Fluctuations
2009
A nonlinear multi scale analysis of a controllable solid rocket motor operating in conditions ranging from high-amplitude fluctuations in combustion chamber to conditions lying in limit cycle is presented and the motor behavior subsequent to some relevant nozzle operations is investigated. Effects of acoustic-vorticity-entropy wave coupling, wave steepening, rotational/viscous flow losses, steep-fronted wave losses are taken into account and oscillatory energy losses in pintle-nozzle, unsteady combustion and chamber geometry changes resulting from grain regression are included. The analysis provides evidence that the unsteady energy balance and the motor wave amplitude evolution are influen…