In this paper we investigate the efficient realization of sampling methods, based on solutions of certain adjoint problems. This adjoint approach does not require the explicit knowledge of a Green’s function for the background medium, and allows to sample for all points and all dipole directions simultaneously; thus several limitations of standard sampling methods are relieved. A detailed deriv...

The analytic properties of adjoint solutions are examined for the quasi-onedimensional Euler equations. For shocked flow, the derivation of the adjoint problem reveals that the adjoint variables are continuous with zero gradient at the shock, and that an internal adjoint boundary condition is required at the shock. A Green’s function approach is used to derive the analytic adjoint solutions cor...

The formulation and solution of the adjoint problem for unsteady flow simulations using the Reynolds-averaged Navier-Stokes equations in the presence of dynamically deforming unstructured meshes is demonstrated. A discrete adjoint approach is used, and the full linearization is built up in a systematic and modular fashion. Discrete conservation in the analysis problem is ensured through the geo...

Simulations of pure-gauge SU(2) lattice gauge theory are performed in the minimal Coulomb gauge. This leaves a residual or remnant gauge symmetry still active which is global in three directions but still local in one. Using averaged fourth-dimension pointing links as a spin-like order parameter, the remnant symmetry appears to undergo spontaneous symmetry breaking at around β = 2.6. Both the B...

This paper explores the use of nonparallel adjoint methods to predict the receptivity of two and three-dimensional boundary layers. Solutions obtained from both adjoint Navier–Stokes (ANS) and adjoint parabolized stability equations (APSE) have been validated against linearized Navier–Stokes (LNS) solutions that provide a full description of the linear receptivity process. The adjoint methods a...

We consider self-adjoint singularly perturbed two-point boundary value problems in conservation form. Highest possible order of uniform convergence for such problems achieved hitherto, via fitted operator methods, was one (see, e.g., [Doolan et al. Uniform numerical methods for problems with initial and boundary layers, Boole Press, Dublin, 1980], p. 121]). Reducing the original problem into th...

A neural approach to propositional multi-adjoint logic programming was recently introduced. In this paper we extend the neural approach to multi-adjoint deduction and, furthermore, modify it to cope with abductive multi-adjoint reasoning, where adaptations of the uncertainty factor in a knowledge base are carried out automatically so that a number of given observations can be adequately explained.

Considering different implication operators, such as Lukasiewicz, Gödel or product implication in the same logic program, naturally leads to the allowance of several adjoint pairs in the lattice of truthvalues. In this paper we apply this idea to introduce multi-adjoint logic programs as an extension of monotonic logic programs. The continuity of the immediate consequences operators is proved a...

‎in this paper‎, ‎we study spectral element approximation for a constrained‎ ‎optimal control problem in one dimension‎. ‎the equivalent a posteriori error estimators are derived for‎ ‎the control‎, ‎the state and the adjoint state approximation‎. ‎such estimators can be used to‎ ‎construct adaptive spectral elements for the control problems.

Multi-adjoint logic programming represents a very recent, extremely exible attempt for introducing fuzzy logic into logic programming. Inspired by previous approaches largely used in other (crisp) declarative paradigms, in this paper we propose the development of a fold/unfold based transformation system for optimizing such kind of fuzzy logic programs. We prove that our set of transformation r...