Characterizing the visualization techniques of project-related interactions

All construction projects can be considered as cooperative undertakings. Their strategic management as well as the daily operations causes numerous interactions to occur, either among persons or among persons and resources. These interactions have been studied from various viewpoints but few researchers have focused on their visualization. The graphical representation of the cooperation is however a powerful tool to help the project participants to get a correct understanding of the situation. This paper proposes thus a structuring framework (IVF Interaction Visualization Framework) of the visualization techniques used to display such interactions. Three basic axes of classification are used to structure the study. Which objects are visualized? Why are they visualized? How are they visualized? For each axis, several properties have been identified and the admitted values have been specified. This work can be considered as a first step towards a structured view of the ‘visualization of cooperation’ domain. C o n st ru ct io n I n fo rm at ic s D ig it al L ib ra ry h tt p :/ /i tc . s ci x. n et entific field. Classifications structure domains of systematic inquiry and provide concepts for developing theories to identify anomalies and to predict future research needs. ’ Wehrend and Lewis (1990) explain that, with a common conceptual framework, ‘workers in any area can place their techniques, so that abstract similarities among problems in different application areas can be identified, and new techniques can be readily transported across application lines’. Gruia-Catalin and Cox (1992) mention that a taxonomy is a ‘vehicle through which we carry out a systematic review of current systems, techniques, trends, and ideas . ’. In any scientific domain, taxonomies are necessary for multiple reasons, among which the most important are probably: − allowing a systematic and rigorous review of current techniques and ideas; − positioning specific works in the whole research field; − clarifying the concepts of the field, which is a required step before elaborating a new theory; − identifying similarities and differences among the research findings; − pointing out new research directions; − highlighting lacks in research proposals. This list is certainly not exhaustive but it is believed to include the most significant elements and it offers enough good reasons to reflect on a new taxonomy. 3 VISUALIZATION IN AEC RESEARCH First of all, it may be useful to remind the scope of some scientific domains dealing with graphics and data. Card, Mackinlay and Shneiderman (1999), who are among the most renowned authors in this field, define ‘visualization’ as ‘the use of computersupported, interactive, visual representations of data to amplify cognition’. They also propose a list of working definitions aiming to clarify the relationships among the concepts related to information visualization. The most useful of them in the context of this paper are the following. ‘Scientific visualization’ concerns ‘the use of interactive visual representations of scientific data, typically physically based, to amplify cognition’. ‘Information visualization’ deals with ‘the use of interactive visual representations of abstract, non physically based data to amplify cognition’. These generic definitions can be instantiated in the specific case of the AEC research field. According to the above-mentioned definitions, the visualization of physical artifacts (e.g. steel structure, heat transfer properties of a building, building site spatial organization) belongs to the scientific visualization discipline. This domain encompasses most of the research works on visualization in AEC. For instance, numerous papers can be found on Computer Aided Design, Virtual Reality, Building Rendering or Lighting Simulation (cf. for instance, ITCon 2003; eCAADe 2004). The information visualization domain has a completely different purpose. It regroups the initiatives aiming to graphically represent abstract objects, such as meetings, document storage systems, e-mails or access to shared documents. This aspect has been notably less studied in the AEC research field. In fact, most of the time, this issue is tackled as a side effect of the study of information exchanges. For instance, project web sites (PWS) obviously include some information visualization (InfoVis) techniques but, in almost all the cases, PWS have been studied in terms of real usage, efficiency, or cost (e.g. Andresen et al. 2003) rather than in terms of InfoVis techniques. Similarly, project planning has been intensively explored with various techniques, such as Petri nets (Rueppel et al. 2004), knowledge base system (Castro & Dawood 2004), and scientific visualization techniques (e.g. adding temporal properties to a 3-D representation to show the state of the building site at a given moment of time). Few researchers, however, focused on the best manner to graphically represent the interactions between the actors. The choice of traditional representations, like Gant charts, is often taken for granted and is rarely questioned in order to assess the appropriateness of these InfoVis techniques to convey information in the situation under study. The research work described in this paper relates to the information visualization field. It aims to study the visualizations techniques used to display the interactions occurring during a project. Therefore, the concept of ‘interaction’, which is a central element of the research work, has to be defined. In this paper, an ‘interaction’ is defined as ‘any kind of communication or exchange among two or more actors, or between one or many actor(s) and some resources used in the project’. Typical examples of such interactions are phone calls between an architect and a contractor, e-mail exchanges between a project manager and the project members, face-toface meetings between the project manager and the client, successive operations on a document located on a web site, or planning modification requests by some project participants.