Reasoning about Action: An Argumentation - Theoretic Approach

We present a uniform non-monotonic solution to the problems of reasoning about action on the basis of an argumentation-theoretic approach. Our theory is provably correct relative to a sensible minimisation policy introduced on top of a temporal propositional logic. Sophisticated problem domains can be formalised in our framework. As much attention of researchers in the field has been paid to the traditional and basic problems in reasoning about actions such as the frame, the qualification and the ramification problems, approaches to these problems within our formalisation lie at heart of the expositions presented in this paper

SUSTAINABILITY IN ACCOUNTING – BASIS: A CONCEPTUAL FRAMEWORK

This paper motivation is to introduce a few guidelines of a model in search for aconceptual framework for sustainability reporting. We are presenting the levels of informationreliability witch are derived mainly from accounting conceptual frameworks, and Global ReportingInitiative (GRI) Guidelines. As the study methodology we are using an inductive approach: weanalyze the qualitative characteristics of specific environmental indicators, in order to assess thedegree of relevance and reliability of each particular provision. We will finally make an attempt toderive the objective of sustainability reporting, while evaluating the degree of usefulness of this typeof documents that closely follow the more formalized process of financial reporting. We concludethat there are a number of reasons for not reporting; most of these are related to internal datareliability. Hence, stakeholders cannot distinguish between different types of data unreliability; andthe GRI does little on this matter.Sustainability, Global Reporting Initiative (GRI) Guidelines, conceptual framework, inductiveapproach

TALplanner in IPC-2002: Extensions and Control Rules

TALplanner is a forward-chaining planner that relies on domain knowledge in the shape of temporal logic formulas in order to prune irrelevant parts of the search space. TALplanner recently participated in the third International Planning Competition, which had a clear emphasis on increasing the complexity of the problem domains being used as benchmark tests and the expressivity required to represent these domains in a planning system. Like many other planners, TALplanner had support for some but not all aspects of this increase in expressivity, and a number of changes to the planner were required. After a short introduction to TALplanner, this article describes some of the changes that were made before and during the competition. We also describe the process of introducing suitable domain knowledge for several of the competition domains

Description Logic Actions with general TBoxes: a Pragmatic Approach

Action formalisms based on description logics (DLs) have recently been introduced as decidable fragments of well-established action theories such as the Situation Calculus and the Fluent Calculus. However, existing DL action formalisms fail to include general TBoxes, which are the standard tool for formalising ontologies in modern description logics. We define a DL action formalism that admits general TBoxes, propose an approach to addressing the ramification problem that is introduced in this way, and perform a detailed investigation of the decidability and computational complexity of reasoning in our formalism

Local Perspectives on Actions

Giving an account of agents acting in the world—sensing, planning, com-municating, doing—requires a coordinated account of, at least, three differ-ent kinds of action: ontic, epistemic, and communicative, which focus, re-spectively, on fact, knowledge and communication. In this note we are concerned primarily with ontic actions. The motivat-ing example is the STRIPS approach to the frame problem, where actions are restricted to change only specified fluents. We present an algebraic setting for ontic actions modeled as relations de-scribing controlled state change. We start from a standard model that encodes STRIPS updates to address the frame problem in logical terms. This model is a system, in the sense of Resende and Baltag. We describe a structure that introduces a notion of local perspective or experiment. This provides a novel treatment of causal relations (which are closely related to integrity constraints and domain axioms in the AI-planning literature). We show how this local structure arises naturally from the semantic struc-ture of the set of possible states, and suggest that it may also help in modeling agents with different perspectives.

A Strategy for Implementing description Temporal Dynamic Algorithms in Dynamic Knowledge Graphs by SPIN

Planning and reasoning about actions and processes, in addition to reasoning about propositions, are important issues in recent logical and computer science studies. The widespread use of actions in everyday life such as IoT, semantic web services, etc., and the limitations and issues in the action formalisms are two factors that lead us to study how actions are represented. Since 2007, there have been some ideas to integrate Description Logic (DL) and action formalisms for representing both static and dynamic knowledge. Meanwhile, time is an important factor in dynamic situations, and actions change states over time. In this study, on the one hand, we examined related logical structures such as extensions of description logics (DLs), temporal formalisms, and action formalisms. On the other hand, we analyzed possible tools for designing and developing the Knowledge and Action Base (KAB). For representation and reasoning about actions, we embedded actions into DLs (such as Dynamic-ALC and its extensions). We propose a terminable algorithm for action projection, planning, checking the satisfiability, consistency, realizability, and executability, and also querying from KAB. Actions in this framework were modeled with SPIN and added to state space. This framework has also been implemented as a plugin for the Prot\'eg\'e ontology editor. During the last two decades, various algorithms have been presented, but due to the high computational complexity, we face many problems in implementing dynamic ontologies. In addition, an algorithm to detect the inconsistency of actions' effects was not explicitly stated. In the proposed strategy, the interactions of actions with other parts of modeled knowledge, and a method to check consistency between the effects of actions are presented. With this framework, the ramification problem can be well handled in future works

Action, Time and Space in Description Logics

Description Logics (DLs) are a family of logic-based knowledge representation (KR) formalisms designed to represent and reason about static conceptual knowledge in a semantically well-understood way. On the other hand, standard action formalisms are KR formalisms based on classical logic designed to model and reason about dynamic systems. The largest part of the present work is dedicated to integrating DLs with action formalisms, with the main goal of obtaining decidable action formalisms with an expressiveness significantly beyond propositional. To this end, we offer DL-tailored solutions to the frame and ramification problem. One of the main technical results is that standard reasoning problems about actions (executability and projection), as well as the plan existence problem are decidable if one restricts the logic for describing action pre- and post-conditions and the state of the world to decidable Description Logics. A smaller part of the work is related to decidable extensions of Description Logics with concrete datatypes, most importantly with those allowing to refer to the notions of space and time

Perceptual Artifacts and Phenomena: Gibson's Role in the 20th Century

One of lit " JJl<>:>l i"flu"ntial f,dU'l""'od,,, for lite "tudy of pe'''''p-lion has been James J. Gibson's ecological approach. This approach is noi a theory, but a melatheory, of ho..... we perceive and under-stand the \\TOrld around us through our senses. As a melalhoory it dissolves old problems and creatl'S new ones, fostering neW ways 10 think about perception and creating 00..... antinomies 10 ponder. This essay outlines the successes of the approach, SOme of its ne..... problems, and traces so:ne of its more and less fruilfulleads. The ancient problem of.pace perception became my burden. It was worrisome, for, as [ gradually came 10 realize, nothing of any practical value was known by psychologists aboulthe perception of motion, or of locomotion in ~pau " or of spact ' itself (Gibson, 1967, p. 133). Z31 With this autobiographical sta tement James J. Gibson described the Lunu",lrum th " t faLw him IIlOl'e tha " 25 years earlier, in 1941, while se-rv

Decision making behaviour in team sports : informational constraints and the dynamics of interpersonal coordination in rugby union

Doutoramento em Motricidade Humana na especialidade de Ciências do DesportoThis thesis aimed to investigate informational variables that constrain the dynamics of interpersonal coordination underlying players’ decision-making behaviour in team sports. We begin with a position paper highlighting the need for understanding how performers interact and generate goal-directed adaptive behaviours coupled to the information sources unfolding in the performance contexts. Thereafter, in all empirical studies performer-environment interactions are analysed with process-tracing methods to examine behaviours’ dynamics. Relevant variables expressing players’ behavioural interactions were identified and analysed in matches and rugby sub-phases (i.e., 1vs1, 1vs2, 3vs3). Analysis of the distance gained dynamics in attacking phases of actual matches revealed that ball displacement provides information on team successful performance. Besides, this variable dynamics described the functional coordination between players and teams. Using also actual match data, the functional role of gap closing information during 1vs1 sub-phases was analysed. Time-to-contact between attacker and defender was suggested as yielding information about future pass possibilities. In an in situ simulation of 1vs2 sub-phase, the manipulation of the initial distance between defenders demonstrated that decision-making behaviours are differently expressed as a function of changes made in participants’ spatial location. This gave evidence for the flexible and adaptive nature of players’ goal-directed behaviour to current task constraints. Finally, observations of participants performing a virtual reality simulation of 3vs3 sub-phase revealed how opening of gaps in the defensive line shapes decision-making behaviour of the ball-carrier. An expertise effect was demonstrated for perceiving and acting upon affordances. In conclusion, this body of research found that decision-making behaviour emerges sustained by specific spatial-temporal information from goal-directed interactions between players.Esta tese teve como objectivo investigar variáveis informacionais que constrangem a dinâmica da coordenação interpessoal subjacente ao comportamento decisional dos jogadores em desportos de equipa. Começamos com um artigo de opinião enfatizando a necessidade de se compreender como os atletas interagem e geram comportamentos intencionais e adaptativos acoplados a fontes de informação presentes nos contextos de performance. Em todos os estudos empíricos que se seguem, são analisadas interacções atleta-envolvimento com métodos de seguimento do processo para examinar a dinâmica do comportamento. Foram identificadas e analisadas variáveis relevantes expressando as interacções comportamentais dos jogadores em jogos e subfases de rugby (i.e., 1x1, 1x2, 3x3). Análise da dinâmica da “distância ganha” em fases de ataque do jogo formal revelou que o deslocamento da bola fornece informação sobre o desempenho de sucesso das equipas. A dinâmica desta variável manifestou-se também caracterizadora da coordenação funcional entre jogadores e equipas. Utilizando ainda dados recolhidos em jogo, foi analisado o papel funcional da informação proveniente de espaços em encerramento durante subfases de 1x1. O tempo-para-contacto entre atacante e defesa foi sugerido como contendo informação sobre possibilidades de passe. Numa simulação in situ de subfases de 1x2, a manipulação da distância inicial entre defesas demonstrou que os comportamentos decisionais são expressos distintamente em função de mudanças efectuadas nas localizações espaciais dos participantes. Isto forneceu evidência da natureza flexível e adaptativa do comportamento intencional dos jogadores em relação aos constrangimentos da tarefa presentes. Finalmente, a observação de jogadores a desempenhar uma subfase de 3x3 virtualmente simulada relevaram que espaços que surgem na linha defensiva moldam o comportamento decisional do jogador com bola. Um efeito de perícia foi demonstrado para a percepção e acção sobre affordances. Em conclusão, este corpo de investigação verificou que o comportamento decisional emerge de informação espácio-temporal específica que resulta das interacções intencionais entre jogadores.FCT - Fundação para a Ciência e a Tecnologi