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John Derrick – One of the best experts on this subject based on the ideXlab platform.

Proving linearisability via coarsegrained abstraction
arXiv: Logic in Computer Science, 2012CoAuthors: Brijesh Dongol, John DerrickAbstract:Linearisability has become the standard safety criterion for concurrent data structures ensuring that the effect of a concrete operation takes place after the execution some Atomic Statement (often referred to as the linearisation point). Identification of linearisation points is a nontrivial task and it is even possible for an operation to be linearised by the execution of other concurrent operations. This paper presents a method for verifying linearisability that does not require identification of linearisation points in the concrete code. Instead, we show that the concrete program is a refinement of some coarsegrained abstraction. The linearisation points in the abstraction are straightforward to identify and the linearisability proof itself is simpler due to the coarse granularity of its Atomic Statements. The concrete finegrained program is a refinement of the coarsegrained program, and hence is also linearisable because every behaviour of the concrete program is a possible behaviour its abstraction.

Proving linearisability without linearisation points An intervalbased approach
, 2012CoAuthors: Brijesh Dongol, John Derrick, Lindsay Groves, Ian J. HayesAbstract:Linearisability has become the standard safety condition for concurrent data structures, which ensures that the effect of a concrete operation takes place after the execution some Atomic Statement (often referred to as the linearisation point) of a concurrent operation. Identification of linearisation points is a nontrivial task and it is even possible for an operation to be linearised by the execution of other concurrent operations. This paper presents a verification method where we verify linearisability of a coarsegrained abstraction of the concurrent data structure; the linearisation points in the coarsegrained abstraction are straightforward to identify. We then show that the concrete finegrained program is an implementation of the coarsegrained abstraction.
Brijesh Dongol – One of the best experts on this subject based on the ideXlab platform.

Proving linearisability via coarsegrained abstraction
arXiv: Logic in Computer Science, 2012CoAuthors: Brijesh Dongol, John DerrickAbstract:Linearisability has become the standard safety criterion for concurrent data structures ensuring that the effect of a concrete operation takes place after the execution some Atomic Statement (often referred to as the linearisation point). Identification of linearisation points is a nontrivial task and it is even possible for an operation to be linearised by the execution of other concurrent operations. This paper presents a method for verifying linearisability that does not require identification of linearisation points in the concrete code. Instead, we show that the concrete program is a refinement of some coarsegrained abstraction. The linearisation points in the abstraction are straightforward to identify and the linearisability proof itself is simpler due to the coarse granularity of its Atomic Statements. The concrete finegrained program is a refinement of the coarsegrained program, and hence is also linearisable because every behaviour of the concrete program is a possible behaviour its abstraction.

Proving linearisability without linearisation points An intervalbased approach
, 2012CoAuthors: Brijesh Dongol, John Derrick, Lindsay Groves, Ian J. HayesAbstract:Linearisability has become the standard safety condition for concurrent data structures, which ensures that the effect of a concrete operation takes place after the execution some Atomic Statement (often referred to as the linearisation point) of a concurrent operation. Identification of linearisation points is a nontrivial task and it is even possible for an operation to be linearised by the execution of other concurrent operations. This paper presents a verification method where we verify linearisability of a coarsegrained abstraction of the concurrent data structure; the linearisation points in the coarsegrained abstraction are straightforward to identify. We then show that the concrete finegrained program is an implementation of the coarsegrained abstraction.
Richard F. W. Bader – One of the best experts on this subject based on the ideXlab platform.

Transferability of group energies and satisfaction of the virial theorem
Chemical Physics Letters, 2003CoAuthors: Fernando Cortésguzmán, Richard F. W. BaderAbstract:The theory of atoms in molecules equates the energy of a group to the negative of its electronic kinetic energy, using the Atomic Statement of the virial theorem. In general, a correction must be applied because of the failure of the wave function to satisfy the virial theorem. This Letter examines the transferability of group energies using selfconsistently scaled wave functions that satisfy the virial theorem at both single determinant and correlated levels of theory to demonstrate that apparent deviations in the transferability of the group energies found in certain homologous systems, is an artefact arising from the variation in the virial correction factor.

Variational principle and path integrals for atoms in molecules
International Journal of Quantum Chemistry, 1992CoAuthors: P. F. Zou, Richard F. W. BaderAbstract:Two things were done in this paper: (i) A generalization of Schwinger’s variational principle to a subsystem was developed within the framework of quantum field theory and applied to the theory of atoms in molecules. This work generalizes the previous derivation given in the Schrodinger formulation. (ii) It is demonstrated that Feynman’s path integral, when expressed in terms of the coherentstate representation, can be constructed for a subsystem of a manyelectron system if a divergence term, which serves as a variational constraint in the definition of an atom in a molecule, is added to the Lagrangian. This formulation is equivalent to the Atomic Statement of the variational principle if the divergence term is suitably constructed. It is shown that the path integral can be expressed as a product of the individual Atomic contributions to the steps along the paths with the action being determined by a corresponding sum of the Atomic contributions to the action integral. © 1992 John Wiley & Sons, Inc.