Revisiting the Parameterized Complexity of Maximum-Duo Preservation String Mapping

In the Maximum-Duo Preservation String Mapping (Max-Duo PSM) problem, the input consists of two related strings A and B of length n and a nonnegative integer k. The objective is to determine whether there exists a mapping m from the set of positions of A to the set of positions of B that maps only to positions with the same character and preserves at least k duos, which are pairs of adjacent positions. We develop a randomized algorithm that solves Max-Duo PSM in time 4^k * n^{O(1)}, and a deterministic algorithm that solves this problem in time 6.855^k * n^{O(1)}. The previous best known (deterministic) algorithm for this problem has running time (8e)^{2k+o(k)} * n^{O(1)} [Beretta et al., Theor. Comput. Sci. 2016]. We also show that Max-Duo PSM admits a problem kernel of size O(k^3), improving upon the previous best known problem kernel of size O(k^6)

28th Annual Symposium on Combinatorial Pattern Matching : CPM 2017, July 4-6, 2017, Warsaw, Poland

Peer reviewe

Performance measurement in construction research & development: The use of case study research approach

The process of finding solutions to the research problem does not follow a clear sequential approach, but often takes unexpected turns due to the uncertainties of the research process and its outcomes. However, appropriate research design would be able to identify any problems and pitfalls that the researcher may come across during the process. In this regard, consideration of the research philosophy pertaining to the study helps a researcher in choosing the appropriate approach for a study. Not only the philosophical stance, but also the research problem under investigation and its underling circumstances influence the selection of a research approach. Accordingly, this paper discusses the factors that drive the selection of a case study as the research approach with particular reference to the use of single case study to undertake an in depth inquiry regarding the impact of performance measurement towards construction research and development. Further, this paper discusses the incorporation of multi-phase, multi perspective and multi-method approaches within the single case study to build valid theory