A new parallel sorting algorithm based upon min-mid-max operations

[[abstract]]In this paper we propose a new parallel sorting algorithm which is based upon an operation which sorts three elements. This algorithm is similar to the parallel odd-even merge sorting algorithm proposed by Batcher, except in the latter, the basic operation sorts only two elements. The correctness of our algorithm is also proved. This research work was partially supported by a grant from the National Science Council, Republic of China under the contract NSC73-0201-E007-01

The pp-Center Problem in Tree Networks Revisited

We present two improved algorithms for weighted discrete $p$-center problem for tree networks with $n$ vertices. One of our proposed algorithms runs in $O(n \log n + p \log^2 n \log(n/p))$ time. For all values of $p$, our algorithm thus runs as fast as or faster than the most efficient $O(n\log^2 n)$ time algorithm obtained by applying Cole's speed-up technique [cole1987] to the algorithm due to Megiddo and Tamir [megiddo1983], which has remained unchallenged for nearly 30 years. Our other algorithm, which is more practical, runs in $O(n \log n + p^2 \log^2(n/p))$ time, and when $p=O(\sqrt{n})$ it is faster than Megiddo and Tamir's $O(n \log^2n \log\log n)$ time algorithm [megiddo1983]