Search results for " inequality."
showing 10 items of 809 documents
Optimal passive-damping design using a decentralized velocity-feedback H-infinity approach
2012
In this work, a new strategy to design passive energy dissipation systems for vibration control of large structures is presented. The method is based on the equivalence between passive damping systems and fully decentralized static velocity-feedback controllers. This equivalence allows to take advantage of recent developments in static output-feedback control design to formulate the passive-damping design as a single optimization problem with Linear Matrix Inequality constraints. To illustrate the application of the proposed methodology, a passive damping system is designed for the seismic protection of a five-story building with excellent results. Peer Reviewed
Nonexistence Results for Higher Order Fractional Differential Inequalities with Nonlinearities Involving Caputo Fractional Derivative
2021
Higher order fractional differential equations are important tools to deal with precise models of materials with hereditary and memory effects. Moreover, fractional differential inequalities are useful to establish the properties of solutions of different problems in biomathematics and flow phenomena. In the present work, we are concerned with the nonexistence of global solutions to a higher order fractional differential inequality with a nonlinearity involving Caputo fractional derivative. Namely, using nonlinear capacity estimates, we obtain sufficient conditions for which we have no global solutions. The a priori estimates of the structure of solutions are obtained by a precise analysis …
Gradient estimates for solutions to quasilinear elliptic equations with critical sobolev growth and hardy potential
2015
This note is a continuation of the work \cite{CaoXiangYan2014}. We study the following quasilinear elliptic equations \[ -\Delta_{p}u-\frac{\mu}{|x|^{p}}|u|^{p-2}u=Q(x)|u|^{\frac{Np}{N-p}-2}u,\quad\, x\in\mathbb{R}^{N}, \] where $1<p<N,0\leq\mu<\left((N-p)/p\right)^{p}$ and $Q\in L^{\infty}(\R^{N})$. Optimal asymptotic estimates on the gradient of solutions are obtained both at the origin and at the infinity.
Irregular Time Dependent Obstacles
2010
Abstract We study the obstacle problem for the Evolutionary p-Laplace Equation when the obstacle is discontinuous and does not have regularity in the time variable. Two quite different procedures yield the same solution.
The 30 Year Search for the Compact Object in SN 1987A
2018
Despite more than 30 years of searches, the compact object in Supernova (SN) 1987A has not yet been detected. We present new limits on the compact object in SN 1987A using millimeter, near-infrared, optical, ultraviolet, and X-ray observations from ALMA, VLT, HST, and Chandra. The limits are approximately 0.1 mJy ($0.1\times 10^{-26}$ erg s$^{-1}$ cm$^{-2}$ Hz$^{-1}$) at 213 GHz, 1 Lsun ($6\times 10^{-29}$ erg s$^{-1}$ cm$^{-2}$ Hz$^{-1}$) in optical if our line-of-sight is free of ejecta dust, and $10^{36}$ erg s$^{-1}$ ($2\times 10^{-30}$ erg s$^{-1}$ cm$^{-2}$ Hz$^{-1}$) in 2-10 keV X-rays. Our X-ray limits are an order of magnitude less constraining than previous limits because we use a…
Les inégalités sociales à l'école : des analyses sociologiques aux interrogations politiques
2003
03067; National audience
Social Inequality in French Education : Extent and Complexity of the Issues
2007
Educational inequality is a matter of acute concern in France as it is in most democratic countries. We rely on schools to assess the skill levels of all students and on this basis to guide them into employment in a way which is impartial and independent of their social origins. However, since the end of the 1960s, French sociology has very cogently denounced sharp and persistent inequalities both in access to different levels of education and in academic success understood more narrowly. This critique took the form of a general theory, presented by Bourdieu and Passeron in 1970 in Reproduction, which made social inequalities a necessary outcome of the way in which school systems worked.
L'influence de l'origine sociale sur les performances scolaires : par où passe-t-elle ?
2006
Using PISA 2000 data, this study presents an international comparison of the way social origin influences reading comprehension performances, looking at a variety of variables, some external to the school system, others internal. A variable's effect is strong in proportion to the strength of its association to father's occupation and degree to which it favors performance. The study uses the method of path analysis to distinguish between these two aspects. The French situation is presented, then compared to twelve other European Union countries. In all countries, social origin influences performance much more strongly through external variables than variables internal to the educational syst…
Aid for trade policy in developing and least developed countries: A GTAP simulation analysis
2011
Recent global initiatives on debt relief and development assistance call for increasing aid for trade to the poorest countries. We apply a multi-country computable general equilibrium model, to analyze if aid for trade offers the possibility that, instead of the developing and least developed countries’ being worse off—as so many were as the result of the last round of trade negotiations—they will actually be better off. Alternative aid for trade scenarios have been evaluated in terms of effectiveness and equity. Our findings show that aid for trade policies expand trade and alleviate inequalities. The developing and least developed countries will benefit mainly from aid for trade assistanc…
Facilitators of and Barriers to Sustainable Development in Small and Medium-Sized Enterprises: A Descriptive Exploratory Study in Romania
2021
In the context of growing concerns regarding the deterioration of the environment and the increase in social inequalities, the concept of sustainability emerged as a response of companies, in order to contribute to community goodwill. The drivers and obstacles for the businesses engaging in sustainable policies have been explored at large by scientific literature. However, research gaps were observed, namely regarding SMEs, that tend to have a less formal and more fragmented approach to sustainability. The goal of our study is to determine the main barriers and facilitators for sustainability that Romanian SMEs face, and the connections between them and with the firms’ characteristics. Our …