Equal-channel angular pressing (ECAP) was one of severe plastic deformation method in order to increase the mechanical properties solid metal without changing its dimension and adding any alloy elements. The change on ECAPed metals caused by lattice strain, so that strain investigation recommended for evaluating metals. In this study, pure titanium rod treated ECAP with Bc route two passes. Bef...

Parallel strategies based on Givens rotations are proposed for updating the QR decomposition of an n × n matrix after a rank-k change (k < n). The complexity analyses of the Givens algorithms are based on the total number of Givens rotations applied to a 2-element vector. The algorithms, which are extensions of the rank-1 updating method, achieve the updating using approximately 2(k + n) compou...

One-parameter families fx of diffeomorphisms of the Euclidean plane are known to have a complicated bifurcation pattern as X varies near certain values, namely where homoclinic tangencies are created. We argue that the bifurcation pattern is much more irregular than previously reported. Our results contrast with the monotonicity result for the wellunderstood one-dimensional family gx(x) = Àx (I...

A variety of relationships between graph parameters involving packings, perfect neighbourhood, irredundant and R-annihilated sets is obtained. Some of the inequalities are improvements of existing bounds for the lower irredundance number, and others are motivated by the conjecture (recently disproved) that for any graph the smallest cardinality of a perfect neighbourhood set is at most the lowe...

In his dissertation, Wadge defined a notion of guessability on subsets of the Baire space and gave two characterizations of guessable sets. A set is guessable iff it is in the second ambiguous class (∆2), iff it is eventually annihilated by a certain remainder. We simplify this remainder and give a new proof of the latter equivalence. We then introduce a notion of guessing with an ordinal limit...

Lattice defects generated by radiation damage can diffuse to grain boundaries (GBs) and be annihilated at GBs. However, the precise role of GBs in annihilating the segregated defects remains unclear. Here, we employed multi-scale models to determine how interstitials are annihilated at small-angle tilt GBs (STGBs) in SiC. First of all, we found the pipe diffusion of interstitials in STGBs is sl...