WWW/Internet - Portal do Software Público Brasileiro

IADIS International Conference WWW/Internet 2010Research in modeling WISs is being done on several levels. Of interest to our work is the modeling ofWISs in ways that allow the shaping of the system to the user and the platform in use while preserving thequality standards of software design. For example, in (Lin, 2008) the materialization of a web system isabstracted by a set of design patterns. These patterns can be applied as a starting point of the design of thespecific system, considering that they provide a solution to a common and usually broadly met problem. Themajor disadvantage of this kind of approach is that the collection of generic design patterns is limited andmay not address all the problems of design. In (Calvary, 2003), a framework – Cameleon ReferenceFramework – for describing multi-target user interfaces is presented. The framework follows an objectorientedapproach, modeling at an abstract level the domain of the problem in terms of objects and therelationships between them. Moreover, the behavior of the system is modeled at the level of task comprisingthe description of a set of inter-related tasks. UsiXML (Molina, 2005) is a language used to describe abstractuser interfaces which are independent from the hardware and software platform in use, the physicalenvironment where the interaction takes place and the user’s abilities.The model presented by this paper follows a different approach in that it models the dynamics of eachindividual entity in the system separately. The behavior of the overall system is never modeled as a whole,but decided by the end user during her/his interaction with the system on the basis of the possible actions s/hecan perform on each entity. Moreover, the model allows the localization of a WIS on four levels: problemdomain, end user’s role and culture and the platform in use.2. THE DESIGN MODEL PROPOSEDThe section proposes an abstraction model to be used for designing WISs localized to the problem domainthe system is a solution for, to the end users’ profiles (in terms of their role and culture) and to the platform inuse. The model is defined by a hierarchy of levels of abstraction (Figure 1). Each level is described by one ormore XML-based languages which make possible the definition and localization of the virtual systems to theend users’ profiles (domain, role, culture and platform). The hierarchy of levels is organized using a topdownapproach, following the description of the web system from the most abstract level of definition to itsconcrete instantiation.Figure 1. The hierarchy of abstraction levels of the design model proposed1). The top level – the meta-model level – describes the rules for defining domain-specific languages ableto define WISs, seen as web spaces in which tools to support domain knowledge-related activities are madeavailable to the end users. This level prescribes how to define the common structure of WISs, describingthem as web spaces and abstracting from their end users’ roles and cultures and the platforms in use. Themeta-model level is defined by a meta-language – Interaction Multimodal Markup Language (IM 2 L). IM 2 L isused for defining domain-specific object languages at the domain level.2). The domain level localizes the WISs to a specific domain. In each domain, end users may havedifferent roles. At the domain level, the common characteristics of the web space defined for end users113