This paper proposes a new actor-critic-style algorithm called Dual Actor-Critic or Dual-AC. It is derived in a principled way from the Lagrangian dual form of the Bellman optimality equation, which can be viewed as a two-player game between the actor and a critic-like function, which is named as dual critic. Compared to its actor-critic relatives, Dual-AC has the desired property that the actor...

In this paper, the meshless integral method based on the regularized boundary integral equation [1] has been extended to analyze the large deformation of elastoplastic materials. The updated Lagrangian governing integral equation is obtained from the weak form of elastoplasticity based on Green-Naghdi’s theory over a local sub-domain, and the moving least-squares approximation is used for meshl...

A finite element analysis of the large deformation of three-dimensional polycrystals is presented using pixel-based finite elements as well as finite elements conforming with grain boundaries. The macroscopic response is obtained through volumeaveraging laws. A constitutive framework for elasto-viscoplastic response of single crystals is utilized along with a fully-implicit Lagrangian finite el...

In this report we present performance measurements of our parallel predictive-corrective incompressible SPH (PCISPH) implementation. PCISPH is an incompressible fluid simulation method based on the Lagrangian SPH model. In this method, incompressibility is enforced by using a prediction-correction scheme to determine the particle pressures. The information about density fluctuations is actively...

General variational theorems for the rate problem of classical elastoplastic. ity al nnite strains, in both Updated Lagransian (UL) and Total Lagrangian (TL) rate fonns, and in terms of alternate measures of stress-rate and conjugate strain-rates, are cri tically studied from the point of view of their applica. tion. Attention, is primarily focused on the derivation of consistent complementary ...

Anisotropic, elasto-viscoplastic behaviour in polycrystalline materials is modelled using a new, updated Lagrangian formulation based on a three-field form of the Hu-Washizu variational principle to create a stable finite element method in the context of nearly incompressible behaviour. The meso-scale is characterized by a representative volume element, which contains grains governed by single ...

Interfacial damage nucleation and evolution in reinforced elastomers is modeled using a three-dimensional updated Lagrangian finite element formulation based on the perturbed Petrov–Galerkin method for the treatment of nearly incompressible behavior. The progressive failure of the particle–matrix interface is modeled by a cohesive law accounting for mode mixity. The meso-scale is characterized ...

QCD finite energy sum rules, together with the latest updated ALEPH data on hadronic decays of the tau-lepton are used in order to determine the vacuum condensates of dimension d = 2 and d = 4. These data are also used to check the validity of the Weinberg sum rules, and to determine the chiral condensates of dimension d = 6 and d = 8, as well as the chiral correlator at zero momentum, proporti...

We review simulations of dynamical domain wall fermions at a fixed inverse lattice spacing of 1.73GeV and with pion masses as light as 330MeV and spatial dimensions as large as 2.7fm performed by the RBC and UKQCD collaborations. These results include pseudoscalar masses and decay constants and low energy constants of the chiral effective lagrangian. We also review results for the neutral kaon ...

A Lagrangian-type numerical scheme called the "comoving mesh method" or CMM is developed for numerically solving certain classes of moving boundary problems which include, example, classical Hele-Shaw flow problem and well-known mean curvature problem. This finite element exploits idea that normal velocity field can be extended throughout entire domain definition using, instance, Laplace operat...