Towards a multicentric quality framework for legal information portals: An application to the DACH region

Legal Information Portals (LIPs) are central information offerings that give various user groups digital access to the law, including legislation, legal acts, or even court decisions. LIPs could provide access to complex legal content in a user-friendly yet accurate way, while exploiting the benefits of open data to enable easy access to legal content for other applications. However, the development of LIPs traditionally adheres to formal legal criteria, leaving users out in the cold. As a result, even the most modern LIPs fall short of providing a user-centric offering. To address this issue, we present a multicentric quality framework to help providers develop and evaluate LIPs by assessing their data quality, data portability, and usability. We apply the framework to the LIPs of Germany, Austria, and Switzerland (the DACH region: D: Deutschland [Germany], A: Austria, CH: Confoederatio Helvetica [Switzerland]) to illustrate its use and identify quality differences between their current systems. Our quality framework for LIPs helps decision-makers better understand and exploit the possibilities for the dissemination of legal information as part of their open justice initiatives. We contribute to the literature by complementing previous conceptual works with a concrete, comprehensive measurement schema that also serves as a basis for assessing user requirements and data portability configurations in other domains with high content complexity

Energy image density property and the lent particle method for Poisson measures

We introduce a new approach to absolute continuity of laws of Poisson functionals. It is based on the {\it energy image density} property for Dirichlet forms and on what we call {\it the lent particle method} which consists in adding a particle and taking it back after some calculation.Comment: 29

Laws of crack motion and phase-field models of fracture

Recently proposed phase-field models offer self-consistent descriptions of brittle fracture. Here, we analyze these theories in the quasistatic regime of crack propagation. We show how to derive the laws of crack motion either by using solvability conditions in a perturbative treatment for slight departure from the Griffith threshold, or by generalizing the Eshelby tensor to phase-field models. The analysis provides a simple physical interpretation of the second component of the classic Eshelby integral in the limit of vanishing crack propagation velocity: it gives the elastic torque on the crack tip that is needed to balance the Herring torque arising from the anisotropic interface energy. This force balance condition reduces in this limit to the principle of local symmetry in isotropic media and to the principle of maximum energy release rate for smooth curvilinear cracks in anisotropic media. It can also be interpreted physically in this limit based on energetic considerations in the traditional framework of continuum fracture mechanics, in support of its general validity for real systems beyond the scope of phase-field models. Analytical predictions of crack paths in anisotropic media are validated by numerical simulations. Simulations also show that these predictions hold even if the phase-field dynamics is modified to make the failure process irreversible. In addition, the role of dissipative forces on the process zone scale as well as the extension of the results to motion of planar cracks under pure antiplane shear are discussed

Fractional BV spaces and first applications to scalar conservation laws

The aim of this paper is to obtain new fine properties of entropy solutions of nonlinear scalar conservation laws. For this purpose, we study some "fractional $BV$ spaces" denoted $BV^s$, for $0 < s \leq 1$, introduced by Love and Young in 1937. The $BV^s(\R)$ spaces are very closed to the critical Sobolev space $W^{s,1/s}(\R)$. We investigate these spaces in relation with one-dimensional scalar conservation laws. $BV^s$ spaces allow to work with less regular functions than BV functions and appear to be more natural in this context. We obtain a stability result for entropy solutions with $BV^s$ initial data. Furthermore, for the first time we get the maximal $W^{s,p}$ smoothing effect conjectured by P.-L. Lions, B. Perthame and E. Tadmor for all nonlinear degenerate convex fluxes

Long time behaviour of viscous scalar conservation laws

This paper is concerned with the stability of stationary solutions of the conservation law $\partial_t u + \mathrm{div}_y A(y,u) -\Delta_y u=0$, where the flux $A$ is periodic with respect to its first variable. Essentially two kinds of asymptotic behaviours are studied here: the case when the equation is set on $\R$, and the case when it is endowed with periodic boundary conditions. In the whole space case, we first prove the existence of viscous stationary shocks - also called standing shocks - which connect two different periodic stationary solutions to one another. We prove that standing shocks are stable in $L^1$, provided the initial disturbance satisfies some appropriate boundedness conditions. We also extend this result to arbitrary initial data, but with some restrictions on the flux $A$. In the periodic case, we prove that periodic stationary solutions are always stable. The proof of this result relies on the derivation of uniform $L^\infty$ bounds on the solution of the conservation law, and on sub- and super-solution techniques.Comment: 36 page

Existence and uniqueness for a nonlinear parabolic/Hamilton-Jacobi coupled system describing the dynamics of dislocation densities

We study a mathematical model describing the dynamics of dislocation densities in crystals. This model is expressed as a one-dimensional system of a parabolic equation and a first order Hamilton-Jacobi equation that are coupled together. We show the existence and uniqueness of a viscosity solution among those assuming a lower-bound on their gradient for all time including the initial data. Moreover, we show the existence of a viscosity solution when we have no such restriction on the initial data. We also state a result of existence and uniqueness of an entropy solution of the system obtained by spatial derivation. The uniqueness of this entropy solution holds in the class of ``bounded from below'' solutions. In order to prove these results, we use a relation between scalar conservation laws and Hamilton-Jacobi equations, mainly to get some gradient estimates. This study takes place on $\R$, and on a bounded domain with suitable boundary conditions