Specialization in i* strategic rationale diagrams

ER 2012 Best Student Paper AwardThe specialization relationship is offered by the i* modeling language through the is-a construct defined over actors (a subactor is-a superactor). Although the overall meaning of this construct is highly intuitive, its semantics when it comes to the fine-grained level of strategic rationale (SR) diagrams is not defined, hampering seriously its appropriate use. In this paper we provide a formal definition of the specialization relationship at the level of i* SR diagrams. We root our proposal over existing work in conceptual modeling in general, and object-orientation in particular. Also, we use the results of a survey conducted in the i* community that provides some hints about what i* modelers expect from specialization. As a consequence of this twofold analysis, we identify, define and specify two specialization operations, extension and refinement, that can be applied over SR diagrams. Correctness conditions for them are also clearly stated. The result of our work is a formal proposal of specialization for i* that allows its use in a well-defined mannerPeer ReviewedAward-winningPostprint (author’s final draft

The notion of specialization in the i*framework

This thesis provides a formal proposal for the specialization relationship in the i* framework that allows its use in a well-defined manner. I root my proposal over existing works in different areas that are interested in representing knowledge: knowledge representation from Artificial Intelligence and conceptual modeling and object-oriented programming languages from Software Development. Also, I use the results of a survey conducted in the i* community that provides some insights about what i* modelers expect from specialization. As a consequence of this twofold analysis, I identify three specialization operations: extension, refinement and redefinition. For each of them, I: - motivate its need and provide some rationale; - distinguish the several cases that can occur in each operation; - define the elements involved in each of these cases and the correctness conditions that must be fulfilled; - demonstrate by induction the fulfilment of the conditions identified for preserving satisfaction; - provide some illustrative examples in the context of an exemplar about travel agencies and travelers. The specialization relationship is offered by the i* framework through the is-a construct defined over actors (a subactor is-a superactor) since it was first released. Although the overall meaning of this construct is highly intuitive, its effects at the level of intentional elements and dependencies are not always clear, hampering seriously its appropriate use. In order to be able to reason about correctness and satisfaction, I define previously the conditions that must be preserved when a specialization takes place. In addition, I provide a methodology with well-defined steps that contextualize the formal aspects of this thesis in a development process. As a conclusion, this thesis is making possible the use of the specialization relationship in i* in a precise, non-ambiguous manner

Specialization in the iStar2.0 language

iStar2.0 has been proposed as a standard language for building goal- and agent-oriented models. It is an evolution of the former i* language, with the purpose of homogenising existing syntactical and semantic variations of basic i* constructs that researchers in the field introduced along the years. In its first version (2016), iStar2.0 was intentionally kept simple, and some constructs were merely introduced but not formally defined. One of them is the notion of specialization. The specialization relationship is offered by iStar2.0 through the is-a construct defined over actors (subactor x is-a superactor y). Although the overall meaning of this construct is highly intuitive, its semantics when it comes to the fine-grained level of the models is not defined in the standard. In this paper we provide a formal definition of the specialization relationship ready to be incorporated into a next release of the iStar2.0 standard language. We root our proposal over existing work on conceptual modeling in general, and object-orientation in particular. Also, we use the results of a survey that provides some hints about what definition do iStar2.0 modelers expect from specialization. As a consequence of this twofold analysis, we identify, define and specify a set of specialization operations that can be applied over iStar2.0 models. Correctness conditions for them are also formally stated. The result of our work is a formal proposal of specialization for iStar2.0 that allows its use in a well-defined manner and contributes to its standardization.Peer ReviewedPostprint (published version

Agent oriented programming: An overview of the framework and summary of recent research

This is a short overview of the agent-oriented programming (AOP) framework. AOP can be viewed as an specialization of object-oriented programming. The state of an agent consists of components called beliefs, choices, capabilities, commitments, and possibly others; for this reason the state of an agent is called its mental state. The mental state of agents is captured formally in an extension of standard epistemic logics: beside temporalizing the knowledge and belief operators, AOP introduces operators for commitment, choice and capability. Agents are controlled by agent programs, which include primitives for communicating with other agents. In the spirit of speech-act theory, each communication primitive is of a certain type: informing, requesting, offering, etc. This document describes these features in more detail and summarizes recent results and ongoing AOP-related work

Semantic networks

AbstractA semantic network is a graph of the structure of meaning. This article introduces semantic network systems and their importance in Artificial Intelligence, followed by I. the early background; II. a summary of the basic ideas and issues including link types, frame systems, case relations, link valence, abstraction, inheritance hierarchies and logic extensions; and III. a survey of ‘world-structuring’ systems including ontologies, causal link models, continuous models, relevance, formal dictionaries, semantic primitives and intersecting inference hierarchies. Speed and practical implementation are briefly discussed. The conclusion argues for a synthesis of relational graph theory, graph-grammar theory and order theory based on semantic primitives and multiple intersecting inference hierarchies