Resource-allocation capabilities of commercial project management software. An experimental analysis

When project managers determine schedules for resource-constrained projects, they commonly use commercial project management software packages. Which resource-allocation methods are implemented in these packages is proprietary information. The resource-allocation problem is in general computationally difficult to solve to optimality. Hence, the question arises if and how various project management software packages differ in quality with respect to their resource-allocation capabilities. None of the few existing papers on this subject uses a sizeable data set and recent versions of common software packages. We experimentally analyze the resource-allocation capabilities of Acos Plus.1, AdeptTracker Professional, CS Project Professional, Microsoft Office Project 2007, Primavera P6, Sciforma PS8, and Turbo Project Professional. Our analysis is based on 1560 instances of the precedence- and resource-constrained project scheduling problem RCPSP. The experiment shows that using the resource-allocation feature of these packages may lead to a project duration increase of almost 115% above the best known feasible schedule. The increase gets larger with increasing resource scarcity and with increasing number of activities. We investigate the impact of different complexity scenarios and priority rules on the project duration obtained by the software packages. We provide a decision table to support managers in selecting a software package and a priority rule.

Die Abschrift als Schreibszene. Der ›Nuwe Parzifal‹ in der Handschrift Rom, Biblioteca Casanatense, Mss. 1409

The Codex Biblioteca Casanatense 1409 which has for a long time been neg- lected in Parzival scholarship, transmits German translations of three continuations of Chre ́tien de Troyes��� Roman de Perceval ou Le Conte du Graal together with the last two books (XV/XVI) of Wolfram von Eschenbach’s Parzival. This article supports the for- merly casually made assumption that the Casanatense manuscript is in fact a direct copy of Codex Donaueschingen 97, the so called Rappoltsteiner Parzifal. As is to be shown, marks in the Donaueschingen codex, as well as significant copying errors in the Casanatense text and its treatment of initials suggest a direct relationship of the two witnesses. The notion of ,writing scene‘ (Schreibszene) with its implications of linguistic semantics, instrumentality, gesture and self reflection, proposed in modern literary scholarship, can help to understand peculiarities of the copying process in the Casanatensis, such as the numerous conceptual abbreviations and the adaptations in the handling of headings. In the final part of the article, the hypothesis is corroborated, that the copy of the Casa- natensis might have been produced in the surroundings of Lamprecht von Brunn (ca. 1320–1399), bishop of Strasburg and Bamberg, and counsellor of the emperor Charles IV.