Why Dosage Matters Nutrition education, in a public health context, is intended to influence large segments of the general population where they live, work and play. Educators face many challenges as they seek to engage people with varying degrees of interest and motivation in activities designed to change their eating habits. The intervention literature offers numerous examples of modest take-...

The running time for solving constraint satisfaction problems (CSP) and propositional satisfiability problems (SAT) using systematic backtracking search has been shown to exhibit great variability. Randomization and restarts is an effective technique for reducing such variability to achieve better expected performance. Several restart strategies have been proposed and studied in previous work a...

We propose and analyse a hybrid numerical–asymptotic hp boundary element method (BEM) for time-harmonic scattering of an incident plane wave by an arbitrary collinear array of sound-soft twodimensional screens. Our method uses an approximation space enriched with oscillatory basis functions, chosen to capture the high-frequency asymptotics of the solution. We provide a rigorous frequencyexplici...

Tax-Benefit Systems in Europe and the US: Between Equity and Efficiency Whether observed differences in redistributive policies across countries are the result of differences in social preferences or efficiency constraints is an important question that paves the debate about the optimality of welfare regimes. To shed new light on this question, we estimate labor supply elasticities on microdata...

When suucient computing power is available, dynamic simulation can be used as a source of motion for real-time, interactive virtual environments. In this paper, we explore techniques for reducing the computational cost of simulating groups of creatures by using less accurate simulations for individuals when they are less important to the viewer or to the action in the virtual world. The less ac...

Acoustic wave scattering problems arise in application areas as diverse as the modelling of sonar, acoustic noise barriers, and ultrasound. In many practical applications the characteristic length scale L of the domain is large compared to the wavelength  . In such cases the small dimensionless wavelength L /  leads to oscillatory solutions. In order to resolve these solutions, standard numer...

Optimal control methods are generally too expensive to be applied on-line and in real-time to the control of robots. An alternative method consists in tuning a parametrized reactive controller so that it converges to optimal behavior. In this paper we present such a method based on the “direct Policy Search” paradigm to get a cost-efficient control policy for a simulated two degrees-of-freedom ...

Variations on space-time Discontinuous Galerkin (STDG) discretization associated to Runge-Kutta schemes are developed. These new schemes while keeping the original scheme order can improve accuracy and stability. Numerical analysis is made on academic test cases and efficiency of these schemes are shown on propagating pressure waves. AMS subject classifications: 52B10, 65D18, 68U05, 68U07

We give an intrinsic algebraic definition of fault detectability and isolability, parity equations, and residuals for time-invariant linear systems. The applicability and efficiency of our approach are illustrated by numerical simulations for three academic examples and a concrete case-study. Keywords— Linear system, fault diagnosis, detectability, isolation, parity equations, residuals, module...

In this paper, we introduce a novel acceleration method for the calculation of dyadic Green’s functions for the mixed potential integral equation formulation of electromagnetic scattering of scatterers embedded in a multilayered medium. Numerical results are provided to demonstrate the efficiency and accuracy of the proposed method. c © 2000 Academic Press