Organizations redesign and building of information systems

Develop software is still a risky business. After 60 years of experience, this community is still not able to consistently build Information Systems (IS) for organizations with predictable quality, within previously agreed budget and time constraints. Although software is changeable we are still unable to cope with the amount and complexity of change that organizations demand for their IS. To improve results, developers followed two alternatives: Frameworks that increase productivity but constrain the flexibility of possible solutions; Agile ways of developing software that keep flexibility with less upfront commitments. With strict frameworks, specific hacks have to be put in place to get around the framework construction options. In time this leads to inconsistent architectures that are harder to maintain due to incomplete documentation and human resources turnover. The main goals of this work is to create a new way to develop flexible IS for organizations, using web technologies, in a faster, better and cheaper way that is more suited to handle organizational change. To do so we propose an adaptive object model that uses a new ontology for data and action with strict normalizing rules. These rules should bound the effects of changes that can be better tested and therefore corrected. Interfaces are built with templates of resources that can be reused and extended in a flexible way. The “state of the world” for each IS is determined by all production and coordination acts that agents performed over time, even those performed by external systems. When bugs are found during maintenance, their past cascading effects can be checked through simulation, re-running the log of transaction acts over time and checking results with previous records. This work implements a prototype with part of the proposed system in order to have a preliminary assessment its feasibility and limitations.

Rapid prototyping of ubiquitous computing environments

Ubiquitous computing raises new usability challenges that cut across design and development. We are particularly interested in environments enhanced with sensors, public displays and personal devices. How can prototypes be used to explore the users' mobility and interaction, both explicitly and implicitly, to access services within these environments? Because of the potential cost of development and design failure, these systems must be explored using early assessment techniques and versions of the systems that could disrupt if deployed in the target environment. These techniques are required to evaluate alternative solutions before making the decision to deploy the system on location. This is crucial for a successful development, that anticipates potential user problems, and reduces the cost of redesign. This thesis reports on the development of a framework for the rapid prototyping and analysis of ubiquitous computing environments that facilitates the evaluation of design alternatives. It describes APEX, a framework that brings together an existing 3D Application Server with a modelling tool. APEX-based prototypes enable users to navigate a virtual world simulation of the envisaged ubiquitous environment. By this means users can experience many of the features of the proposed design. Prototypes and their simulations are generated in the framework to help the developer understand how the user might experience the system. These are supported through three different layers: a simulation layer (using a 3D Application Server); a modelling layer (using a modelling tool) and a physical layer (using external devices and real users). APEX allows the developer to move between these layers to evaluate different features. It supports exploration of user experience through observation of how users might behave with the system as well as enabling exhaustive analysis based on models. The models support checking of properties based on patterns. These patterns are based on ones that have been used successfully in interactive system analysis in other contexts. They help the analyst to generate and verify relevant properties. Where these properties fail then scenarios suggested by the failure provide an important aid to redesign.