There has been many strategies used in trying to obtain good solutions for the TSP (Traveling Salesman Problem). The best strategy that runs in polynomial time for general TSP instances is Chained Lin-Kernighan, but it does not always find the optimal solution. We look at hybrid method based on combining multiple runs of (Chained) Lin-Kernighan and Branch-and-Bound in hopes of obtaining an opti...

In this paper, we explore the method of combining the replication and parity approaches to tolerate multiple disk failures in a disk array. In addition to the conventional mirrored and chained declustering methods , a method based on the hybrid of mirrored-and-chained declustering is explored. A performance study that explores the eeect of combining replication and parity approaches is conducte...

This paper considers output based tracking control for an experimental underactuated H-drive manipulator. This manipulator can be transformed into a so-called second-order chained form by a coordinateand feedback transformation. An observer is proposed to solve the output feedback problem for systems in second-order chained form. For the designed observer global stability of the closed loop sys...

let r be an associative ring with unity. an element a in r is said to be r-clean if a = e+r, where e is an idempotent and r is a regular (von neumann) element in r. if every element of r is r-clean, then r is called an r-clean ring. in this paper, we prove that the concepts of clean ring and r-clean ring are equivalent for abelian rings. further we prove that if 0 and 1 are the only idempotents...

let r be an associative ring with unity. an element a in r is said to be r-clean if a = e+r, where e is an idempotent and r is a regular (von neumann) element in r. if every element of r is r-clean, then r is called an r-clean ring. in this paper, we prove that the concepts of clean ring and r-clean ring are equivalent for abelian rings. further we prove that if 0 and 1 are the only idempotents...

in this work, we investigate the transfer of some homological properties from a ring $r$ to its amalgamated duplication along some ideal $i$ of $r$ $rbowtie i$, and then generate new and original families of rings with these properties.

for a ring endomorphism $alpha$ and an $alpha$-derivation $delta$, we introduce a concept, so called skew $pi$-armendariz ring, that is a generalization of both $pi$-armendariz rings, and $(alpha,delta)$-compatible skew armendariz rings. we first observe the basic properties of skew $pi$-armendariz rings, and extend the class of skew $pi$-armendariz rings through various ring extensions. we nex...