Daniele Porello | University of Genoa (original) (raw)

Papers by Daniele Porello

arXiv: Logic in Computer Science, 2017

This work contributes to the theory of judgment aggregation by discussing a number of significant... more This work contributes to the theory of judgment aggregation by discussing a number of significant non-classical logics. After adapting the standard framework of judgment aggregation to cope with non-classical logics, we discuss in particular results for the case of Intuitionistic Logic, the Lambek calculus, Linear Logic and Relevant Logics. The motivation for studying judgment aggregation in non-classical logics is that they offer a number of modelling choices to represent agents' reasoning in aggregation problems. By studying judgment aggregation in logics that are weaker than classical logic, we investigate whether some well-known impossibility results, that were tailored for classical logic, still apply to those weak systems.

When people combine concepts these are often characterised as “hybrid”, “impossible”, or “humorou... more When people combine concepts these are often characterised as “hybrid”, “impossible”, or “humorous”. However, when simply considering them in terms of extensional logic, the novel concepts understood as a conjunctive concept will often lack meaning having an empty extension (consider “a tooth that is a chair”, “a pet flower”, etc.). Still, people use different strategies to produce new non-empty concepts: additive or integrative combination of features, alignment of features, instantiation, etc. All these strategies involve the ability to deal with conflicting attributes and the creation of new (combinations of) properties. We here consider in particular the case where a Head concept has superior ‘asymmetric’ control over steering the resulting concept combination (or hybridisation) with a Modifier concept. Specifically, we propose a dialogical approach to concept combination and discuss an implementation based on axiom weakening, which models the cognitive and logical mechanics of ...

In this paper, we propose an integrated system that interfaces computer vision algorithms for the... more In this paper, we propose an integrated system that interfaces computer vision algorithms for the recognition of simple objects with an ontology that handles the recognition of complex objects by means of reasoning. We develop our theory within a foundational ontology and we present a formalization of the process of conferring meaning

Proceedings of the Thirty-First International Joint Conference on Artificial Intelligence

When considering two concepts in terms of extensional logic, their combination will often be triv... more When considering two concepts in terms of extensional logic, their combination will often be trivial, returning an empty extension. Consider e.g. “a Fish Vehicle”, i.e., “a Vehicle which is also a Fish”. Still, people use sophisticated strategies to produce new, non-empty concepts. All these strategies involve the human ability to mend the conflicting attributes of the input concepts and to create new properties of the combination. We focus in particular on the case where a Head concept has superior ‘asymmetric’ control over steering the resulting combination (or hybridisation) with a Modifier concept. Specifically, we propose a dialogical model of the cognitive and logical mechanics of this asymmetric form of hybridisation. Its implementation is then evaluated using a combination of example ontologies.

A concept is traditionally defined via the necessary and sufficient conditions that clearly deter... more A concept is traditionally defined via the necessary and sufficient conditions that clearly determine its extension. By contrast, cognitive views of concepts intend to account for empirical data that show that categorisation under a concept presents typicality effects and a certain degree of indeterminacy. We propose a formal language to compactly represent concepts by leveraging on weighted logical formulas. In this way, we can model the possible synergies among the qualities that are relevant for categorising an object under a concept. We show that our proposal can account for a number of views of concepts such as the prototype theory and the exemplar theory. Moreover, we show how the proposed model can overcome some limitations of cognitive views.

How can organisations survive not only the substitution of members, but also other dramatic chang... more How can organisations survive not only the substitution of members, but also other dramatic changes, like that of the norms regulating their activities, the goals they plan to achieve, or the system of roles that compose them? This paper is as first step towards a well-founded ontological analysis of the persistence of organisations through changes. Our analysis leverages Kit Fine’s notions of rigid and variable embodiment and proposes to view the (history of the) decisions made by the members of the organisation as the criterion to re-identify the organisation

Weighted Threshold Operators are n-ary logical operators which compute a weighted sum of their ar... more Weighted Threshold Operators are n-ary logical operators which compute a weighted sum of their arguments and verify whether it reaches a certain threshold. These operators have been extensively studied in the context of circuit complexity theory (see e.g. [16]), and they are also known in the neural network community under the alternative name of perceptrons (see e.g. [6]). In [12], threshold operators were studied in the context of Knowledge Representation, focusing in particular on Description Logics (DLs) (see [5] for an introduction to DL). Adding threshold operators to DL is not hard. In brief, if C1 . . . Cn are concept expressions, w1 . . . wn ∈ R are weights, and t ∈ R is a threshold, we can introduce a new concept ∇∇(C1 : w1 . . . Cn : wn) to, semantically, designate those individuals d such that ∑ {wi : Ci applies to d} ≥ t. In the context of DL and concept representation, such threshold (“Tooth”) expressions are natural and useful: they provide a simple way to describe cl...

1. Introduzione Lo studio della natura dei significati e della relazione che li collega alle espr... more 1. Introduzione Lo studio della natura dei significati e della relazione che li collega alle espressioni linguistiche ha da sempre rivestito un ruolo fondamentale nell'analisi dei linguaggi naturali e formali. La semantica cognitiva, rivendicando il ruolo centrale della percezione e della cognizione nella definizione dei significati, ha proposto un'alternativa alla posizione oggettivista e verocondizionale sviluppata in filosofia analitica del linguaggio e in logica classica. I significati non sono entità che esistono nel mondo esterno indipendentemente da ogni processo cognitivo, ma entità mentali che concernono la sfera cognitiva dei singoli individui, strutture concettuali incarnate (embodied) che dipendono da esperienze percettive. L'obiettivo di una semantica cognitiva è un modello semantico che catturi adeguatamente le operazioni cognitive che corrispondono ai costrutti linguistici. In questa prospettiva, il legame tra linguaggio e mondo fisico —il riferimento dell...

We argue that a cognitive semantics has to take into account the possibly partial information tha... more We argue that a cognitive semantics has to take into account the possibly partial information that a cognitive agent has of the world. After discussing Gärdenfors’s view of objects in conceptual spaces, we offer a number of viable treatments of partiality of information and we formalize them by means of alternative predicative logics. Our analysis shows that understanding the nature of simple predicative sentences is crucial for a cognitive semantics.

Product structures are represented in engineering models by depicting and linking components, fea... more Product structures are represented in engineering models by depicting and linking components, features and assemblies. Their understanding requires knowledge of both design and manufacturing practices, and yet further contextual reasoning is needed to read them correctly. Since these representations are essential to the engineering activities, the lack of a clear and explicit semantics of these models hampers the use of information systems for their assessment and exploitation. We study this problem by identifying different interpretations of structure representations, and then discuss the formal properties that a suitable language needs for representing components, features and combinations of these. We show that the representation of components and features require a non-standard mereology.

ArXiv, 2018

Ontology engineering is a hard and error-prone task, in which small changes may lead to errors, o... more Ontology engineering is a hard and error-prone task, in which small changes may lead to errors, or even produce an inconsistent ontology. As ontologies grow in size, the need for automated methods for repairing inconsistencies while preserving as much of the original knowledge as possible increases. Most previous approaches to this task are based on removing a few axioms from the ontology to regain consistency. We propose a new method based on weakening these axioms to make them less restrictive, employing the use of refinement operators. We introduce the theoretical framework for weakening DL ontologies, propose algorithms to repair ontologies based on the framework, and provide an analysis of the computational complexity. Through an empirical analysis made over real-life ontologies, we show that our approach preserves significantly more of the original knowledge of the ontology than removing axioms.

Description Logics, 2019

We introduce a family of operators to combine Description Logic concepts. They aim to characteris... more We introduce a family of operators to combine Description Logic concepts. They aim to characterise complex concepts that apply to instances that satisfy “enough” of the concept descriptions given. For instance, an individual might not have any tusks, but still be considered an elephant. To formalise the meaning of “enough”, the operators take a list of weighted concepts as arguments, and a certain threshold to be met. We commence a study of the formal properties of these operators, and study some variations. The intended applications concern the representation of cognitive aspects of classification tasks: the interdependencies among the attributes that define a concept, the prototype of a concept, and the typicality of the instances.

Frontiers in Artificial Intelligence and Applications, 2020

A thorough understanding of what needs are is fundamental for designing well-behaved information ... more A thorough understanding of what needs are is fundamental for designing well-behaved information systems for many social applications and in particular for public services. Talking about needs pervades indeed the jargon of Public Administrations when motivating their service offering. In this paper, we propose an ontological analysis of needs, aiming at a principled disentangling of the different uses of the term. We leverage philosophical tradition on intentionality, for its rich understanding of mental entities, we compare it with the well-established BDI (Belief-Desire-Intention) tradition in knowledge representation, and we propose a formalisation of needs within the foundational ontology DOLCE. Throughout the paper, we motivate our analysis focusing on needs in public services.

New Frontiers in the Study of Social Phenomena, 2016

Modeling and Using Context, 2015

In knowledge representation, socio-technical systems can be modeled as multiagent systems in whic... more In knowledge representation, socio-technical systems can be modeled as multiagent systems in which the local knowledge of each individual agent can be seen as a context. In this paper we propose formal ontologies as a means to describe the assumptions driving the construction of contexts as local theories and to enable interoperability among them. In particular, we present two alternative conceptualizations of the notion of sociomateriality (and entanglement), which is central in the recent debates on socio-technical systems in the social sciences, namely critical and agential realism. We thus start by providing a model of entanglement according to the critical realist view, representing it as a property of objects that are essentially dependent on different modules of an already given ontology. We refine then our treatment by proposing a taxonomy of sociomaterial entanglements that distinguishes between ontological and epistemological entanglement. In the final section, we discuss the second perspective, which is more challenging form the point of view of knowledge representation, and we show that the very distinction of information into modules can be at least in principle built out of the assumption of an entangled reality.

Lecture Notes in Computer Science, 2015

In this paper, we introduce a logic to reason about group actions for groups that are defined by ... more In this paper, we introduce a logic to reason about group actions for groups that are defined by means of the majority rule. It is well known that majoritarian aggregation is subject to irrationality, as the results in social choice theory and judgment aggregation show. The logic of action that we use here for modelling group actions is based on a substructural propositional logic that allows for preventing inconsistent outcome. Agency is modeled by means of a "bringingit-about" modal logic with coalitions. We show that, in this way, it is possible to obtain a consistent model of agency of groups that are defined in an aggregative manner.

We describe two applications of refinement operators that can generalise and specialise concepts ... more We describe two applications of refinement operators that can generalise and specialise concepts expressed in the ALC description logic language. The first application addresses the problem of analysing the joint coherence of some given concepts w.r.t. a background ontology. To this end, we apply Thagard’s computational theory of coherence, in combination with semantic similarity between concepts defined by means of the generalisation operator. The second application focuses on repairing an inconsistent collective ontology that may result from the vote on axioms of multiple experts based on principles from social choice theory and judgment aggregation. We use the refinement operators, together with a reference ontology, to weaken some axioms and to repair the collective ontology.

In this paper, we discuss the approach based on Social Choice Theory and Judgment Aggregation to ... more In this paper, we discuss the approach based on Social Choice Theory and Judgment Aggregation to the definition of collective reasoning. We shall make explicit the aggregative nature of the notion of collective reasoning that is defined in the Judgment Aggregation account and we shall stress that the notion of logical coherence plays a fundamental role in defining collective attitudes. Unfortunately, as several results in Judgment Aggregation show, coherence is not compatible with fair aggregation procedures. On closer inspection, the notion of coherence that is jeopardized by Judgment Aggregation is based on classical logic. In this work, we propose to revise the standard view of rationality of Judgment Aggregation by exploring the realm of non-classical logics. in particular, we will present possibility results for substructural logics. Those logics, we argue, provide a viable notion of collective reasoning.

Applied Ontology, 2018

We propose a formal framework to examine the relationship between models and observations. To mak... more We propose a formal framework to examine the relationship between models and observations. To make our analysis precise, models are reduced to first-order theories that represent both terminological knowledge-e.g., the laws that are supposed to regulate the domain under analysis and that allow for explanations, predictions, and simulations-and assertional knowledge-e.g., information about specific entities in the domain of interest. Observations are introduced into the domain of quantification of a distinct first-order theory that describes their nature and their organization and takes track of the way they are experimentally acquired or intentionally elaborated. A model mainly represents the theoretical knowledge or hypotheses on a domain, while the theory of observations mainly represents the empirical knowledge and the given experimental practices. We propose a precise identity criterion for observations and we explore different links between models and observations by assuming a degree of independence between them. By exploiting some techniques developed in the field of social choice theory and judgment aggregation, we sketch some strategies to solve inconsistencies between a given set of observations and the assumed theoretical hypotheses. The solutions of these inconsistencies can impact both the observations-e.g., the theoretical knowledge and the analysis of the way observations are collected or produced may highlight some unreliable sources-and the models-e.g., empirical evidences may invalidate some theoretical laws.

We study a fragment of Intuitionistic Linear Logic combined with non-normal modal operators. Focu... more We study a fragment of Intuitionistic Linear Logic combined with non-normal modal operators. Focusing on the minimal modal logic, we provide a Gentzen-style sequent calculus as well as a semantics in terms of Kripke resource models. We show that the proof theory is sound and complete with respect to the class of minimal Kripke resource models. We also show that the sequent calculus allows cut elimination. We put the logical framework to use by instantiating it as a logic of agency. In particular, we apply it to reason about the resource-sensitive use of artefacts.

arXiv: Logic in Computer Science, 2017

This work contributes to the theory of judgment aggregation by discussing a number of significant... more This work contributes to the theory of judgment aggregation by discussing a number of significant non-classical logics. After adapting the standard framework of judgment aggregation to cope with non-classical logics, we discuss in particular results for the case of Intuitionistic Logic, the Lambek calculus, Linear Logic and Relevant Logics. The motivation for studying judgment aggregation in non-classical logics is that they offer a number of modelling choices to represent agents' reasoning in aggregation problems. By studying judgment aggregation in logics that are weaker than classical logic, we investigate whether some well-known impossibility results, that were tailored for classical logic, still apply to those weak systems.

When people combine concepts these are often characterised as “hybrid”, “impossible”, or “humorou... more When people combine concepts these are often characterised as “hybrid”, “impossible”, or “humorous”. However, when simply considering them in terms of extensional logic, the novel concepts understood as a conjunctive concept will often lack meaning having an empty extension (consider “a tooth that is a chair”, “a pet flower”, etc.). Still, people use different strategies to produce new non-empty concepts: additive or integrative combination of features, alignment of features, instantiation, etc. All these strategies involve the ability to deal with conflicting attributes and the creation of new (combinations of) properties. We here consider in particular the case where a Head concept has superior ‘asymmetric’ control over steering the resulting concept combination (or hybridisation) with a Modifier concept. Specifically, we propose a dialogical approach to concept combination and discuss an implementation based on axiom weakening, which models the cognitive and logical mechanics of ...

In this paper, we propose an integrated system that interfaces computer vision algorithms for the... more In this paper, we propose an integrated system that interfaces computer vision algorithms for the recognition of simple objects with an ontology that handles the recognition of complex objects by means of reasoning. We develop our theory within a foundational ontology and we present a formalization of the process of conferring meaning

Proceedings of the Thirty-First International Joint Conference on Artificial Intelligence

When considering two concepts in terms of extensional logic, their combination will often be triv... more When considering two concepts in terms of extensional logic, their combination will often be trivial, returning an empty extension. Consider e.g. “a Fish Vehicle”, i.e., “a Vehicle which is also a Fish”. Still, people use sophisticated strategies to produce new, non-empty concepts. All these strategies involve the human ability to mend the conflicting attributes of the input concepts and to create new properties of the combination. We focus in particular on the case where a Head concept has superior ‘asymmetric’ control over steering the resulting combination (or hybridisation) with a Modifier concept. Specifically, we propose a dialogical model of the cognitive and logical mechanics of this asymmetric form of hybridisation. Its implementation is then evaluated using a combination of example ontologies.

A concept is traditionally defined via the necessary and sufficient conditions that clearly deter... more A concept is traditionally defined via the necessary and sufficient conditions that clearly determine its extension. By contrast, cognitive views of concepts intend to account for empirical data that show that categorisation under a concept presents typicality effects and a certain degree of indeterminacy. We propose a formal language to compactly represent concepts by leveraging on weighted logical formulas. In this way, we can model the possible synergies among the qualities that are relevant for categorising an object under a concept. We show that our proposal can account for a number of views of concepts such as the prototype theory and the exemplar theory. Moreover, we show how the proposed model can overcome some limitations of cognitive views.

How can organisations survive not only the substitution of members, but also other dramatic chang... more How can organisations survive not only the substitution of members, but also other dramatic changes, like that of the norms regulating their activities, the goals they plan to achieve, or the system of roles that compose them? This paper is as first step towards a well-founded ontological analysis of the persistence of organisations through changes. Our analysis leverages Kit Fine’s notions of rigid and variable embodiment and proposes to view the (history of the) decisions made by the members of the organisation as the criterion to re-identify the organisation

Weighted Threshold Operators are n-ary logical operators which compute a weighted sum of their ar... more Weighted Threshold Operators are n-ary logical operators which compute a weighted sum of their arguments and verify whether it reaches a certain threshold. These operators have been extensively studied in the context of circuit complexity theory (see e.g. [16]), and they are also known in the neural network community under the alternative name of perceptrons (see e.g. [6]). In [12], threshold operators were studied in the context of Knowledge Representation, focusing in particular on Description Logics (DLs) (see [5] for an introduction to DL). Adding threshold operators to DL is not hard. In brief, if C1 . . . Cn are concept expressions, w1 . . . wn ∈ R are weights, and t ∈ R is a threshold, we can introduce a new concept ∇∇(C1 : w1 . . . Cn : wn) to, semantically, designate those individuals d such that ∑ {wi : Ci applies to d} ≥ t. In the context of DL and concept representation, such threshold (“Tooth”) expressions are natural and useful: they provide a simple way to describe cl...

1. Introduzione Lo studio della natura dei significati e della relazione che li collega alle espr... more 1. Introduzione Lo studio della natura dei significati e della relazione che li collega alle espressioni linguistiche ha da sempre rivestito un ruolo fondamentale nell'analisi dei linguaggi naturali e formali. La semantica cognitiva, rivendicando il ruolo centrale della percezione e della cognizione nella definizione dei significati, ha proposto un'alternativa alla posizione oggettivista e verocondizionale sviluppata in filosofia analitica del linguaggio e in logica classica. I significati non sono entità che esistono nel mondo esterno indipendentemente da ogni processo cognitivo, ma entità mentali che concernono la sfera cognitiva dei singoli individui, strutture concettuali incarnate (embodied) che dipendono da esperienze percettive. L'obiettivo di una semantica cognitiva è un modello semantico che catturi adeguatamente le operazioni cognitive che corrispondono ai costrutti linguistici. In questa prospettiva, il legame tra linguaggio e mondo fisico —il riferimento dell...

We argue that a cognitive semantics has to take into account the possibly partial information tha... more We argue that a cognitive semantics has to take into account the possibly partial information that a cognitive agent has of the world. After discussing Gärdenfors’s view of objects in conceptual spaces, we offer a number of viable treatments of partiality of information and we formalize them by means of alternative predicative logics. Our analysis shows that understanding the nature of simple predicative sentences is crucial for a cognitive semantics.

Product structures are represented in engineering models by depicting and linking components, fea... more Product structures are represented in engineering models by depicting and linking components, features and assemblies. Their understanding requires knowledge of both design and manufacturing practices, and yet further contextual reasoning is needed to read them correctly. Since these representations are essential to the engineering activities, the lack of a clear and explicit semantics of these models hampers the use of information systems for their assessment and exploitation. We study this problem by identifying different interpretations of structure representations, and then discuss the formal properties that a suitable language needs for representing components, features and combinations of these. We show that the representation of components and features require a non-standard mereology.

ArXiv, 2018

Ontology engineering is a hard and error-prone task, in which small changes may lead to errors, o... more Ontology engineering is a hard and error-prone task, in which small changes may lead to errors, or even produce an inconsistent ontology. As ontologies grow in size, the need for automated methods for repairing inconsistencies while preserving as much of the original knowledge as possible increases. Most previous approaches to this task are based on removing a few axioms from the ontology to regain consistency. We propose a new method based on weakening these axioms to make them less restrictive, employing the use of refinement operators. We introduce the theoretical framework for weakening DL ontologies, propose algorithms to repair ontologies based on the framework, and provide an analysis of the computational complexity. Through an empirical analysis made over real-life ontologies, we show that our approach preserves significantly more of the original knowledge of the ontology than removing axioms.

Description Logics, 2019

We introduce a family of operators to combine Description Logic concepts. They aim to characteris... more We introduce a family of operators to combine Description Logic concepts. They aim to characterise complex concepts that apply to instances that satisfy “enough” of the concept descriptions given. For instance, an individual might not have any tusks, but still be considered an elephant. To formalise the meaning of “enough”, the operators take a list of weighted concepts as arguments, and a certain threshold to be met. We commence a study of the formal properties of these operators, and study some variations. The intended applications concern the representation of cognitive aspects of classification tasks: the interdependencies among the attributes that define a concept, the prototype of a concept, and the typicality of the instances.

Frontiers in Artificial Intelligence and Applications, 2020

A thorough understanding of what needs are is fundamental for designing well-behaved information ... more A thorough understanding of what needs are is fundamental for designing well-behaved information systems for many social applications and in particular for public services. Talking about needs pervades indeed the jargon of Public Administrations when motivating their service offering. In this paper, we propose an ontological analysis of needs, aiming at a principled disentangling of the different uses of the term. We leverage philosophical tradition on intentionality, for its rich understanding of mental entities, we compare it with the well-established BDI (Belief-Desire-Intention) tradition in knowledge representation, and we propose a formalisation of needs within the foundational ontology DOLCE. Throughout the paper, we motivate our analysis focusing on needs in public services.

New Frontiers in the Study of Social Phenomena, 2016

Modeling and Using Context, 2015

In knowledge representation, socio-technical systems can be modeled as multiagent systems in whic... more In knowledge representation, socio-technical systems can be modeled as multiagent systems in which the local knowledge of each individual agent can be seen as a context. In this paper we propose formal ontologies as a means to describe the assumptions driving the construction of contexts as local theories and to enable interoperability among them. In particular, we present two alternative conceptualizations of the notion of sociomateriality (and entanglement), which is central in the recent debates on socio-technical systems in the social sciences, namely critical and agential realism. We thus start by providing a model of entanglement according to the critical realist view, representing it as a property of objects that are essentially dependent on different modules of an already given ontology. We refine then our treatment by proposing a taxonomy of sociomaterial entanglements that distinguishes between ontological and epistemological entanglement. In the final section, we discuss the second perspective, which is more challenging form the point of view of knowledge representation, and we show that the very distinction of information into modules can be at least in principle built out of the assumption of an entangled reality.

Lecture Notes in Computer Science, 2015

In this paper, we introduce a logic to reason about group actions for groups that are defined by ... more In this paper, we introduce a logic to reason about group actions for groups that are defined by means of the majority rule. It is well known that majoritarian aggregation is subject to irrationality, as the results in social choice theory and judgment aggregation show. The logic of action that we use here for modelling group actions is based on a substructural propositional logic that allows for preventing inconsistent outcome. Agency is modeled by means of a "bringingit-about" modal logic with coalitions. We show that, in this way, it is possible to obtain a consistent model of agency of groups that are defined in an aggregative manner.

We describe two applications of refinement operators that can generalise and specialise concepts ... more We describe two applications of refinement operators that can generalise and specialise concepts expressed in the ALC description logic language. The first application addresses the problem of analysing the joint coherence of some given concepts w.r.t. a background ontology. To this end, we apply Thagard’s computational theory of coherence, in combination with semantic similarity between concepts defined by means of the generalisation operator. The second application focuses on repairing an inconsistent collective ontology that may result from the vote on axioms of multiple experts based on principles from social choice theory and judgment aggregation. We use the refinement operators, together with a reference ontology, to weaken some axioms and to repair the collective ontology.

In this paper, we discuss the approach based on Social Choice Theory and Judgment Aggregation to ... more In this paper, we discuss the approach based on Social Choice Theory and Judgment Aggregation to the definition of collective reasoning. We shall make explicit the aggregative nature of the notion of collective reasoning that is defined in the Judgment Aggregation account and we shall stress that the notion of logical coherence plays a fundamental role in defining collective attitudes. Unfortunately, as several results in Judgment Aggregation show, coherence is not compatible with fair aggregation procedures. On closer inspection, the notion of coherence that is jeopardized by Judgment Aggregation is based on classical logic. In this work, we propose to revise the standard view of rationality of Judgment Aggregation by exploring the realm of non-classical logics. in particular, we will present possibility results for substructural logics. Those logics, we argue, provide a viable notion of collective reasoning.

Applied Ontology, 2018

We propose a formal framework to examine the relationship between models and observations. To mak... more We propose a formal framework to examine the relationship between models and observations. To make our analysis precise, models are reduced to first-order theories that represent both terminological knowledge-e.g., the laws that are supposed to regulate the domain under analysis and that allow for explanations, predictions, and simulations-and assertional knowledge-e.g., information about specific entities in the domain of interest. Observations are introduced into the domain of quantification of a distinct first-order theory that describes their nature and their organization and takes track of the way they are experimentally acquired or intentionally elaborated. A model mainly represents the theoretical knowledge or hypotheses on a domain, while the theory of observations mainly represents the empirical knowledge and the given experimental practices. We propose a precise identity criterion for observations and we explore different links between models and observations by assuming a degree of independence between them. By exploiting some techniques developed in the field of social choice theory and judgment aggregation, we sketch some strategies to solve inconsistencies between a given set of observations and the assumed theoretical hypotheses. The solutions of these inconsistencies can impact both the observations-e.g., the theoretical knowledge and the analysis of the way observations are collected or produced may highlight some unreliable sources-and the models-e.g., empirical evidences may invalidate some theoretical laws.

We study a fragment of Intuitionistic Linear Logic combined with non-normal modal operators. Focu... more We study a fragment of Intuitionistic Linear Logic combined with non-normal modal operators. Focusing on the minimal modal logic, we provide a Gentzen-style sequent calculus as well as a semantics in terms of Kripke resource models. We show that the proof theory is sound and complete with respect to the class of minimal Kripke resource models. We also show that the sequent calculus allows cut elimination. We put the logical framework to use by instantiating it as a logic of agency. In particular, we apply it to reason about the resource-sensitive use of artefacts.

JOWO-The Joint Ontology Workshops JOWO 2017-Episode III: The Tyrolean Autumn, was the third editi... more JOWO-The Joint Ontology Workshops JOWO 2017-Episode III: The Tyrolean Autumn, was the third edition of the 'Joint Ontology Workshops', which comprised a confederation of ten ontology workshops. It was hosted by the Free University of Bozen-Bolzano and held between September 21-23, 2017 in Bolzano, Italy. 1 JOWO's mission is to provide a platform for the diverse communities interested in building, reasoning with, and applying formalised ontologies in the wide spectrum of Information Systems, Artificial Intelligence, Philosophy, Linguistics and Cognitive Science, both in theory and applications. The 2017 edition of JOWO collocated workshops that cover a broad spectrum of contemporary applied ontology research, including its philosophical and methodological foundations (FOUST II, DEW), the application of ontologies in particular domains (ODLS, FOMI), the role of ontology in related research areas like cognition (ISD3, EPINON), context (CREOL), data and knowledge (DAO, WINKS), shape and patterns (SHAPES 4.0). JOWO 2017 included the following ten workshops: 2 CREOL International Workshop on Contextual Representation of Objects and Events in Language 3

JOWO 2017—Episode III: The Tyrolean Autumn, was the third edition of the ‘Joint Ontology Workshop... more JOWO 2017—Episode III: The Tyrolean Autumn, was the third edition of the ‘Joint Ontology Workshops’, which comprised a confederation of ten ontology workshops. It was hosted by the Free University of Bozen-Bolzano and held be- tween September 21–23, 2017 in Bolzano, Italy.1 JOWO’s mission is to provide a platform for the diverse communities interested in building, reasoning with, and applying formalised ontologies in the wide spectrum of Information Systems, Artificial Intelligence, Philosophy, Linguistics and Cognitive Science, both in theory and applications.
The 2017 edition of JOWO collocated workshops that cover a broad spectrum of contemporary applied ontology research, including its philosophical and method- ological foundations (FOUST II, DEW), the application of ontologies in par- ticular domains (ODLS, FOMI), the role of ontology in related research areas like cognition (ISD3, EPINON), context (CREOL), data and knowledge (DAO, WINKS), shape and patterns (SHAPES 4.0).

CEUR Workshop Proceedings, 2017

More and more applications require real-time processing of massive, dynamically generated, ordere... more More and more applications require real-time processing of massive, dynamically generated, ordered data, where order is often an essential factor reflecting recency. Data stream management techniques provide reactive and reliable processing mechanisms over such data. Key to their success is the use of streaming algorithms that harness the natural or enforceable​ ​ orders​ ​ in​ ​ the​ ​ data. This trend started to be visible also in the Web, where an increasing number of streaming sources and datasets are becoming available. They originate from social networks, sensor networks, Internet of Things (IoT) and many other technologies that find in the Web a platform for sharing data. This is resulting in new Web-centric efforts such as the Web of Things, which studies how to expose and describe IoT using the Web, or the Social Web, which investigates protocols, vocabularies, and APIs to facilitate access to social functionality as part of the Web. In the Semantic Web context emerged efforts like Stream Reasoning and RDF Stream Processing. Stream Reasoning aims at combing data stream management and semantic technologies to perform reasoning over massive, heterogeneous and dynamic data;, while RDF Stream Processing studies the continuous query answering process​ ​ over​ ​ data​ ​ streams​ ​ modelled​ ​ accordingly​ ​ to​ ​ the​ ​ RDF​ ​ model. The workshop put together such sub-communities to discuss and to investigate holistic processing models for streams over the Web, which consider the issues about publishing data streams on the Web as well as processing them with queries and inference processes. The event has contributed in the creation of an active community interested in integrating stream processing and reasoning by using methods inspired by data and knowledge management. WOMoCoE 2017: Ontology Modularity, Contextuality, and Evolution In the Semantic Web and Linked Data, knowledge is rarely considered to be a monolithic and static entity. Instead, partitioning knowledge into distinct modular structures is central to organize knowledge bases, from the design of the latter to their creation, from their maintenance to their use in knowledge sharing. From a different perspective, representing and reasoning about a context with respect to knowledge in distinct modules is essential for the correct exploitation knowledge bases, and for reliable and effective reasoning in changing situations. Finally, evolution of knowledge resources, in terms of updates by newly acquired knowledge, is an important factor ensuring that over time stored knowledge remains​ ​ meaningful. The 2nd International Workshop on Ontology Modularity, Contextuality, and Evolution (WOMoCoE 2017) provided a forum for practitioners and researchers to discuss current trends in modularity, contextuality, and evolution of knowledge resources. The workshop aimed at bringing together an interdisciplinary audience that is interested in its topics both from​ ​ a​ ​ theoretical,​ ​ formal​ ​ point​ ​ of​ ​ view​ ​ but​ ​ as​ ​ well​ ​ from​ ​ an​ ​ application-oriented​ ​ perspective. WOMoCoE 2017 attracted 5 submissions. Each submission was reviewed by at least three members of the Program Committee, and 4 were accepted for oral presentation at the workshop and are included in this volume. The workshop also featured an invited talk by Pascal​ ​ Hitzler.

JOWO, ‘The Joint Ontology Workshops—Episode I: The Argentine Winter of Ontology’, was held for th... more JOWO, ‘The Joint Ontology Workshops—Episode I: The Argentine Winter of Ontology’, was held for the first time in Buenos Aires, at the 24th International Joint Conference on Artificial Intelligence – IJCAI 2015. Its mission is to join forces of the diverse communities interested in building, reasoning with, and ap- plying formalised ontologies in the wide spectrum of Artificial Intelligence theory and applications.
The present edition of JOWO 2015 collocated four workshops that cover a broad spectrum of contemporary ontology research ranging from philosophical founda- tions to theoretical investigations of reasoning problems to a variety of AI appli- cations of ontologies. JOWO included
OntoLP1 Workshop on Ontologies and logic programming for query answering; OntoChange2 Workshop on Belief Change and Non Monotonic Reasoning in Ontologies and Databases;
WoMO3 Ninth International Workshop on Modular Ontologies; FOfAI4 Workshop on Formal Ontologies for Artificial Intelligence.