This paper presents a simulation study for a resource-constrained project scheduling problem with multiple alternatives. We decide on a set of baseline schedules at the project planning phase, resulting in options to switch between execution modes of activities during project execution. We assess the performance of the set of baseline schedules under general mode implementation disruptions. A simple, yet effective algorithm is presented to construct the set of baseline schedules. Moreover, a general disruption system is proposed to model different disruption types, disruption dependencies and disruption sizes.

In the resource-constrained project scheduling problem with alternative subgraphs (RCPSP-AS), we model alternative execution modes for work packages in the project. In contrast to the traditional RCPSP, the project network consists of different alternative work packages. To that purpose, the scheduling problem selects the best possible alternatives for the construction of the baseline schedule. On top of that, several back-up schedules are created in order to cope with unexpected changes along the project progress. In the presence of uncertainty, we can then switch between these alternative schedules at different decision moments in order to bring the project back on track. The alternative schedules are combined in a set of schedules that should be constructed by the project manager prior to project execution. We present a computational experiment to investigate the ability of using such a set of schedules in the presence of uncertainty during project execution. The experiments indicate that using a set of schedules outperforms the use of a single schedule, even when the uncertainty level is relatively low. The results also show that the composition of this schedule set is important. Therefore, a degree of schedule similarity is proposed to analyse this composition, and results show that a mix of similar and dissimilar schedules performs best. Finally, we show that the solution quality of each schedule in the set has an impact on the performance of the schedule switches given the project disruptions.

Formal Concept Analysis (FCA) is an unsupervised clustering technique and many scientific papers are devoted to applying FCA in Information Retrieval (IR) research. We collected 103 papers published between 2003-2009 which mention FCA and information retrieval in the abstract, title or keywords. Using a prototype of our FCA-based toolset CORDIET, we converted the pdf-files containing the papers to plain text, indexed them with Lucene using a thesaurus containing terms related to FCA research and then created the concept lattice shown in this paper. We visualized, analyzed and explored the literature with concept lattices and discovered multiple interesting research streams in IR of which we give an extensive overview. The core contributions of this paper are the innovative application of FCA to the text mining of scientific papers and the survey of the FCA-based IR research.

In this article, we introduce a framework that can be used by organizations as a positioning instrument to think of business-ICT alignment decisions in light of the strategic importance of ICT (Information and Communication Technology) in their organization. We make a distinction between organizations where ICT is of high strategic importance and those where ICT is of low strategic importance. Based on this difference we argue that heavily investing in business-ICT alignment processes, structures and roles (PSRs) will not necessarily always be beneficial when ICT is of low strategic importance to the business. Furthermore, organizations that have a minimalist approach to the use of ICT do not necessarily need to invest in business-ICT alignment PSRs. We explain the dynamics and possible migration scenarios of our proposed framework after testing the statistical significance of the relationship between the strategic importance of ICT and the investment in business-ICT alignment. We end this article with a short empirical study which combines survey and case study results. Both the framework and framework dynamics still need further empirical validation, preferably with longitudinal data. Therefore, we stress and acknowledge that many of the discussions in this article are still explorative in nature. However, this article illustrates the possibilities and the need for a more fine-grained approach to business-ICT alignment.