Efficient Algorithms for the Sum Selection Problem and k Maximum Sums Problem

Given a sequence of n real numbers A=a1,a2,…,an and a positive integer k, the Sum Selection Problem is to find the segment A(i∗,j∗)=ai∗,ai∗+1,…,aj∗ such that the rank of the sum View the MathML source is k over all View the MathML source segments. We present a deterministic algorithm for this problem that runs in O(nlogn) time. The previously best known result for this problem is a randomized algorithm that runs in expected O(nlogn) time. Applying this algorithm we can obtain a deterministic algorithm for the k Maximum Sums Problem, i.e., the problem of enumerating the k largest sum segments, that runs in O(nlogn+k) time. The previously best known randomized and deterministic algorithms for the k Maximum Sums Problem run respectively in expected O(nlogn+k) time and in worst case O(nlog2n+k) time

Computing the Stretch Factor and Maximum Detour of Paths, Trees, and Cycles in the Normed Space

The stretch factor and maximum detour of a graph G embedded in a metric space measure how well G approximates the minimum complete graph containing G and the metric space, respectively. In this paper we show that computing the stretch factor of a rectilinear path in L1 plane has a lower bound of Ω(n log n) in the algebraic computation tree model and describe a worst-case O(σn log2 n) time algorithm for computing the stretch factor or maximum detour of a path embedded in the plane with a weighted fixed orientation metric defined by σ ≥ 2 vectors and a worst-case O(n logd n) time algorithm to d ≥ 3 dimensions in L1-metric. We generalize the algorithms to compute the stretch factor or maximum detour of trees and cycles in O(σn logd+1 n) time. We also obtain an optimal O(n) time algorithm for computing the maximum detour of a monotone rectilinear path in L1 plane

Evaluating and managing electronic commerce and outsourcing projects in hospitals

© 2019, IGI Global. Despite the huge popularity of outsourcing in electronic commerce/IT in the past two decades, many hospitals have failed to realize the expected benefits from their outsourcing projects. Not surprisingly, the management of electronic commerce/IT outsourcing contracts has become one of the top management issues for hospitals executives in recent years. Hence, the purpose of this study was to provide an overview of outsourcing in electronic commerce/IT investment evaluation and benefits realization processes and practices in Australian and Taiwanese hospitals. Inherent in this study was the opportunity to compare such practices between a developed economy (Australia) and a newly industrialized economy (Taiwan). Several key electronic commerce/IT investment evaluation and outsourcing issues and challenges faced by Australian and Taiwanese hospitals will be presented. The results will assist hospital executives to develop their own approaches and strategies to better manage the opportunities and threats that exist in undertaking electronic commerce/IT outsourcing projects in Australian and Taiwanese hospitals