Angelo Susi

From Laws to Requirements

Legal prescriptions are increasingly impacting on information systems and on organisations that must comply with them in order to avoid to be prosecuted or fined. Addressing law compliance in early phases of the requirements analysis helps in improving the alignment of information systems with the law. In this paper, we point out ontological differences between legal concepts and requirements and set the basis for a systematic process able to support decision making about requirements for law compliant systems.

Automating model transformations in agent-oriented modelling

Current Agent-Oriented Software Engineering (AOSE) methodologies adopt a model-based approach for analysis and design, but, in order to become of practical use, they should include it in a clear and customizable software development process and provide CASE tools that support it. In this regards, the Model-Driven Architecture (MDA) initiative of OMG is providing useful concepts and techniques. The MDA ultimate objective is that of improving quality and software maintainability by allowing for the reuse of models and mappings between models. It offers standards and techniques for model interoperability and for automating model transformations. Our goal in this paper is to address the role of model transformations in AOSE by discussing a practical example, with reference to the Tropos methodology. In particular, we will focus on the automatic transformation of a Tropos plan decomposition into a UML 2.0 activity diagram. We will show how to use the transformation technique to automate model mappings and describe how a CASE tool, based on a modular architecture, has been extended to automate models transformations.

From Stakeholder Needs to Service Requirements

Web services offer a novel open, distributed computing environment. Within that environment, web services need to be discovered and composed in order to meet user needs (or, goals). For example, a user goal may be plan a holiday. To fulfill this goal, several services need to be discovered from different directories, such as book hotel, book flight, rent car and pay by credit card. These then need to be composed into a plan (process). In this work, we adopt and extend an agent-oriented software design methodology (Tropos) and tailor it to the design of web services. We also sketch how Tropos design-time models can support service discovery and composition by offering a roadmap that relates stakeholder goals to collections of services available in different directories. A case study from the literature is used throughout.

Agent-Oriented Modeling by Interleaving Formal and Informal Specification

The goal of this paper is to discuss possibilities of inter-mixing formal and informal specification in order to guide and support the conceptual modeling process in software development. We sketch a framework based on an agent-oriented methodology that provides a modeling language which allows for the definition of both informal and formal specification. We show how formal techniques can be used to guide and support the analyst while building and refining a conceptual model. Examples of its applications are discussed, with reference to the decision making process undertaken by the analyst when performing a set of activities relevant for requirements engineering, such as requirements elicitation and refinement, user validation of requirements specification, or management of requirements evolution. A case study taken from a technology transfer project in the agricultural domain is used to illustrate the approach.

Gathering Requirements for Software Configuration from the Crowd

Todays complex software systems consist of several components that interact in complex ways to provide services to users. In doing so, these systems go through continuous assessment of their context and configure themselves accordingly to keep user satisfaction high. A popular approach to design adaptive software systems is to perform variability modelling, for instance adopting a feature-based approach. Features describe key components and characteristics of a system, which can take different values and be combined in different ways to obtain a system behavior that can best satisfy the needs of different users, who may use the software in different contexts. These design-time models should be complemented by rules that help in deciding when to switch from one valid system configuration to a different one to fit changing user needs or preferences.Eliciting information necessary to build suitable feature models, as well as rules for dynamic reconfigurations that cover relevant scenarios is not an easy task when considering dynamic adaptation in presence of high variability in user profiles. We are experiencing this issue in a project which aims at developing dynamically personalisable software, and specifically a dynamically configurable feedback gathering tool.In this vision paper we propose to use crowdsourcing to elicit knowledge about reconfiguration requirements for dynamically adaptive systems. The proposed approach rests on a two-stage process, which involves the contribution from the crowd of potential system users, as well as from domain experts.

Discovering Requirements through Goal-Driven Process Mining

Software systems are designed to support their users in performing tasks that are parts of more general processes. Unfortunately, software designers often make invalid assumptions about the users processes and therefore about the requirements to support such processes. Eliciting and validating such assumptions through manual means (e.g., through observations, interviews, and workshops) is expensive, time-consuming, and may fail to identify the users real processes. Using process mining may reduce these problems by automating the monitoring and discovery of the actual processes followed by a crowd of users. The Crowd provides an opportunity to involve diverse groups of users to interact with a system and conduct their intended processes. This implicit feedback in the form of discovered processes can then be used to modify the existing systems functionalities and ensure whether or not a software product is used as initially designed. In addition, the analysis of user-system interactions may reveal lacking functionalities and quality issues. These ideas are illustrated on the GreenSoft personal energy management system.