Search results for "bound"

Local regularity estimates for general discrete dynamic programming equations

2022

We obtain an analytic proof for asymptotic H\"older estimate and Harnack's inequality for solutions to a discrete dynamic programming equation. The results also generalize to functions satisfying Pucci-type inequalities for discrete extremal operators. Thus the results cover a quite general class of equations.

On a Robin (p,q)-equation with a logistic reaction

2019

We consider a nonlinear nonhomogeneous Robin equation driven by the sum of a \(p\)-Laplacian and of a \(q\)-Laplacian (\((p,q)\)-equation) plus an indefinite potential term and a parametric reaction of logistic type (superdiffusive case). We prove a bifurcation-type result describing the changes in the set of positive solutions as the parameter \(\lambda \gt 0\) varies. Also, we show that for every admissible parameter \(\lambda \gt 0\), the problem admits a smallest positive solution.

Innovation dynamics in space. Local actors and local factors

1997

This paper addresses the issue of technogenesis and its geographical pattern. It aims to offer both a general analysis framework and a test on innovation data from several European cities. This framework is mainly built on the product life-cycle and the incubation approach. On the basis of this framework, it is argued that the phases of an industrial life-cycle have several firm-specific effects. First, these phases influence innovativeness and thus profit levels, output and employment of firms in a spatially distinct way. Second, the phases of the life-cycle mirror the importance of local factors for innovations, and third, they affect strategic decisions of firms, inter alia by influencin…

Macroalgae production in Northern Europe: Business and government perspectives on how to regulate a novel blue bioeconomy

2022

Macroalgae biomass production, understood as cultivation and harvesting, is a minor industry in Europe at present, but the sector is recognized as having substantial growth potential. Here, we framed the environmental license as a boundary object between business and authorities and investigated the details of macroalgal licensing procedures in seven Northern European countries (Finland, Estonia, Sweden, Germany, Norway, Iceland, and Scotland). We conducted surveys and interviews with macroalgae companies and licensing authorities to understand the challenges faced by both sides. Generally, macroalgae production in Northern European countries is regulated by environmental and water laws and…

Magneto-electric laminates free vibration characterization by dual reciprocity BEM

2010

Solvability of a first order system in three-dimensional non-smooth domains

1985

summary:A system of first order partial differential equations is studied which is defined by the divergence and rotation operators in a bounded nonsmooth domain $\Omega\subset \bold R^3$. On the boundary $\delta\Omega$, the vanishing normal component is prescribed. A variational formulation is given and its solvability is investigated.

A blow-up result for a nonlinear wave equation on manifolds: the critical case

2021

We consider a inhomogeneous semilinear wave equation on a noncompact complete Riemannian manifold (Formula presented.) of dimension (Formula presented.), without boundary. The reaction exhibits the combined effects of a critical term and of a forcing term. Using a rescaled test function argument together with appropriate estimates, we show that the equation admits no global solution. Moreover, in the special case when (Formula presented.), our result improves the existing literature. Namely, our main result is valid without assuming that the initial values are compactly supported.

A coupled discontinuous Galerkin-Finite Volume framework for solving gas dynamics over embedded geometries

2021

Author(s): Gulizzi, Vincenzo; Almgren, Ann S; Bell, John B | Abstract: We present a computational framework for solving the equations of inviscid gas dynamics using structured grids with embedded geometries. The novelty of the proposed approach is the use of high-order discontinuous Galerkin (dG) schemes and a shock-capturing Finite Volume (FV) scheme coupled via an $hp$ adaptive mesh refinement ($hp$-AMR) strategy that offers high-order accurate resolution of the embedded geometries. The $hp$-AMR strategy is based on a multi-level block-structured domain partition in which each level is represented by block-structured Cartesian grids and the embedded geometry is represented implicitly by a…

SPH modeling of blood flow in cerebral aneurysms

Gli aneurismi cerebrali sono dilatazioni patologiche di arterie cerebrali. Queste patologie hanno un intrinseco rischio di rottura con conseguenti emorragie intracraniche. Sebbene i meccanismi di formazione, crescita e rottura degli aneurismi cerebrali non sono ancora del tutto compresi, è comunemente riconosciuto che in questi processi i fattori emodinamici giocano un ruolo molto importante. Le simulazioni numeriche possono fornire utili informazioni sull'emodinamica e possono essere usate per applicazioni cliniche. Nei tradizionali metodi numerici basati su una griglia di calcolo il processo di discretizzazione dei vasi cerebrali sui quali insiste un aneurisma è molto complesso. D’altra p…

Expectation Damages and Bilateral Cooperative Investments

2012

We examine the efficiency of the standard breach remedy expectation damages in a setting where the buyer invests cooperatively and the seller invests both cooperatively and selfishly. Contracts may specify a required quality level and an upper bound to the seller's coordination costs. We find that it is optimal to write an augmented Cadillac contract in which quality is stipulated such that it cannot be met with positive probability together with a very low price. Thus, the seller becomes a residual claimant and the coordination-cost threshold can be used to balance the incentives of the buyer.