We present Neumann-Neumann domain decomposition preconditioners for the solution of elliptic linear quadratic optimal control problems. The preconditioner is applied to the optimality system. A Schur complement formulation is derived that reformulates the original optimality system as a system in the state and adjoint variables restricted to the subdomain boundaries. The application of the Schu...

In the transport layer of the TCP/IP protocol suite, both TCP and UDP use internet checksum to protect headers and data. Internet checksum uses 1’s complement arithmetic to detect errors in the content delivered by the data-link layer. Both research and experience have shown that there are a wide variety of error sources which can not be detected by this lower layer. The error detecting perform...

We deal with the problem of preserving various versions of completeness in (< κ)–support iterations of forcing notions, generalizing the case “S–complete proper is preserved by CS iterations for a stationary costationary S ⊆ ω1”. We give applications to Uniformization and the Whitehead problem. In particular, for a strongly inaccessible cardinal κ and a stationary set S ⊆ κ with fat complement ...

The problem of nding the minimum topology of multipro-cessing substrates supporting parallel execution of any given neighbourhood constrained system is proposed and possible optimal strategies are investigated based on the relationship between Barbosa's scheduling by edge reversal-SER-distributed algorithm and the minimum clique covering problem. It is shown that from any given clique covering ...

The second author’s ω, ∆, χ conjecture proposes that every graph satisties χ ≤ d 1 2 (∆ + 1 + ω)e. In this paper we prove that the conjecture holds for all claw-free graphs. Our approach uses the structure theorem of Chudnovsky and Seymour. Along the way we discuss a stronger local conjecture, and prove that it holds for claw-free graphs with a three-colourable complement. To prove our results ...

Toxoplasma gondii is a land-derived parasite that infects humans and marine mammals. Infections are a significant cause of mortality for endangered southern sea otters (Enhydra lutris nereis), but the transmission mechanism is poorly understood. Otter exposure to T. gondii has been linked to the consumption of marine turban snails in kelp (Macrocystis pyrifera) forests. It is unknown how turban...

BACKGROUND Pyrethroid pesticides are broad-spectrum pest control agents in agricultural production. Both agricultural and residential usage is continuing to grow, leading to the development of insecticide resistance in the pest and toxic effects on a number of nontarget organisms. Thus, it is necessary to hunt suitable enzymes including hydrolases for degrading pesticide residues, which is an e...