ABSTRACT Now-related temporal data play an important role in the medical context. Current relatio... more ABSTRACT Now-related temporal data play an important role in the medical context. Current relational temporal database (TDB) approaches are limited since (i) they (implicitly) assume that the span of time occurring between the time when facts change in the world and the time when the changes are recorded in the database is exactly known, and (ii) do not explicitly provide an extended relational algebra to query now-related data. We propose an approach that, widely adopting AI symbolic manipulation techniques, overcomes the above limitations.
The user has requested enhancement of the downloaded file. All in-text references underlined in b... more The user has requested enhancement of the downloaded file. All in-text references underlined in blue are added to the original document and are linked to publications on ResearchGate, letting you access and read them immediately.
ABSTRACT Now-relative temporal data play an important role in most temporal applications, and the... more ABSTRACT Now-relative temporal data play an important role in most temporal applications, and their management has been proved to impact in a crucial way the efficiency of temporal databases. Though several temporal relational approaches have been developed to deal with now-relative data, none of them has provided a whole temporal algebra to query them. In this paper we overcome such a limitation, by proposing a general algebra which is parametrically adapted to cope with the relational approaches to now-relative data in the literature, i.e., MIN, MAX, NULL and POINT approaches. Besides being general enough to provide a query language for several approaches in the literature, our algebra has been designed in such a way to satisfy several theoretical and practical desiderata: closure with respect to representation languages, correctness with respect to the “consensus” BCDM semantics, reducibility to the standard non-temporal algebra (which involves interoperability with non-temporal relational databases), implementability and efficiency. Indeed, the experimental evaluation we have drawn on our implementation has shown that only a slight overhead is added by our treatment of now-relative data (with respect to an approach in which such data are not present).
In questo articolo viene presentata un'applicazione informatica che esegue automaticamente la... more In questo articolo viene presentata un'applicazione informatica che esegue automaticamente la trascrizione e traslitterazione di un testo in lingua russa. La traslitterazione trasforma il testo scritto in alfabeto cirillico in alfabeto latino, mentre la trascrizione è volta a rispettare il più possibile la pronuncia originaria e indica a un parlante italiano come pronunciare il testo russo. La peculiarità della soluzione proposta risiede nell'uso di un foglio elettronico e delle relative funzioni disponibili, per fornire uno strumento (i) multipiattaforma e (ii) didatticamente valido, in quanto (i) le regole di traslitterazione e trascrizione possono essere adattate ad altre architetture e applicativi e (ii) sono facilmente modificabili da utenti non esperti di informatica. В статье рассматривается компьютерное применение, которое осуществляет автоматически транскрипцию и транслитерацию любого текста на русском языке. Транслитерация перевращает текст написанный кириллицей в ...
Configuration was one of the first tasks successfully approached via AI techniques. However, solv... more Configuration was one of the first tasks successfully approached via AI techniques. However, solving configuration problems can be computationally expensive. In this work, we show that the decomposition of a configuration problem into a set of simpler and mutually independent subproblems can decrease the computational cost of solving it. In particular, we describe a decomposition technique exploiting the compositional structure
ABSTRACT Knowledge-based clinical decision making is one of the most challenging activities of ph... more ABSTRACT Knowledge-based clinical decision making is one of the most challenging activities of physicians. Clinical Practice Guidelines are commonly recognized as a useful tool to help physicians in such activities by encoding the indications provided by evidence ...
Several explanation and interpretation tasks, such as diagnosis, plan recognition and image inter... more Several explanation and interpretation tasks, such as diagnosis, plan recognition and image interpre- tation, can be formalized as abductive and consis- tency reasoning. Some proposals address the prob- lem based on a task-independent representation of a domain which includes an ontology or taxonomy of hypotheses. In this paper we rely on the same type of representation, and we address cost
ABSTRACT In the real world, many phenomena are time related and in the last three decades the dat... more ABSTRACT In the real world, many phenomena are time related and in the last three decades the database community has devoted much work in dealing with “time of facts” in databases. While many approaches incorporating time in the relational model have been already devised, most of them assume that the exact time of facts is known. However, this assumption does not hold in many practical domains, in which temporal indeterminacy of facts occurs. The treatment of valid-time indeterminacy requires in-depth extensions to the current relational approaches. In this paper, we propose a theoretically grounded approach to cope with this issue, overcoming the limitations of related approaches in the literature. In particular, we present a 1NF temporal relational model and propose a new temporal relational algebra to query it. We also formally study the properties of the new data model and algebra, thus granting that our approach is interoperable with pre-existent temporal and non-temporal relational approaches, and is implementable on top of them. Finally, we consider computational complexity, showing that only a limited overhead is added when moving from determinate to indeterminate time.
ABSTRACT Now-related temporal data play an important role in the medical context. Current relatio... more ABSTRACT Now-related temporal data play an important role in the medical context. Current relational temporal database (TDB) approaches are limited since (i) they (implicitly) assume that the span of time occurring between the time when facts change in the world and the time when the changes are recorded in the database is exactly known, and (ii) do not explicitly provide an extended relational algebra to query now-related data. We propose an approach that, widely adopting AI symbolic manipulation techniques, overcomes the above limitations.
Studies in health technology and informatics, 2008
A crucial feature of computerized clinical guidelines (CGs) lies in the fact that they may be use... more A crucial feature of computerized clinical guidelines (CGs) lies in the fact that they may be used not only as conventional documents (as if they were just free text) describing general procedures that users have to follow. In fact, thanks to a description of their actions and control flow in some semiformal representation language, CGs can also take advantage of Computer Science methods and Information Technology infrastructures and techniques, to become executable documents, in the sense that they may support clinical decision making and clinical procedures execution. In order to reach this goal, some advanced planning techniques, originally developed within the Artificial Intelligence (AI) community, may be (at least partially) resorted too, after a proper adaptation to the specific CG needs has been carried out.
Studies in health technology and informatics, 2007
Temporal constraints play a fundamental role in clinical guidelines. For example, temporal indete... more Temporal constraints play a fundamental role in clinical guidelines. For example, temporal indeterminacy, constraints about duration, delays between actions and periodic repetitions of actions are essential in order to cope with clinical therapies. This paper proposes a computer-based approach in order to deal with temporal constraints in clinical guidelines. Specifically, it provides the possibility to represent such constraints and reason with them (i.e., perform inferences in the form of constraint propagation). We first propose a temporal representation formalism and two constraint propagation algorithms operating on it, and then we show how they can be exploited in order to provide clinical guideline systems with different temporal facilities. Our approach offers several advantages: for example, during the guideline acquisition phase, it enables to represent temporal constraints and to check their consistency; during the execution phase, it allows the physician to check the con...
Studies in health technology and informatics, 2007
Representing clinical guidelines is a very complex knowledge-representation task, requiring a lot... more Representing clinical guidelines is a very complex knowledge-representation task, requiring a lot of expertise and efforts. Nevertheless, guideline representations often contain several kinds of errors. Therefore, checking the well-formedness and correctness of a guideline representation is an important task, which can be drastically improved with the adoption of computer programs. In this paper, we discuss the advanced facilities provided by the GLARE system to assist physicians to produce correct representations of clinical guidelines.
Temporal constraints play a fundamental role in clinical guidelines. We sketch a computer-based t... more Temporal constraints play a fundamental role in clinical guidelines. We sketch a computer-based temporal framework to represent temporal information in the guidelines, and to support different forms of inference and query-answering (which, e.g., might help in physician decision making).
ABSTRACT Now-related temporal data play an important role in the medical context. Current relatio... more ABSTRACT Now-related temporal data play an important role in the medical context. Current relational temporal database (TDB) approaches are limited since (i) they (implicitly) assume that the span of time occurring between the time when facts change in the world and the time when the changes are recorded in the database is exactly known, and (ii) do not explicitly provide an extended relational algebra to query now-related data. We propose an approach that, widely adopting AI symbolic manipulation techniques, overcomes the above limitations.
The user has requested enhancement of the downloaded file. All in-text references underlined in b... more The user has requested enhancement of the downloaded file. All in-text references underlined in blue are added to the original document and are linked to publications on ResearchGate, letting you access and read them immediately.
ABSTRACT Now-relative temporal data play an important role in most temporal applications, and the... more ABSTRACT Now-relative temporal data play an important role in most temporal applications, and their management has been proved to impact in a crucial way the efficiency of temporal databases. Though several temporal relational approaches have been developed to deal with now-relative data, none of them has provided a whole temporal algebra to query them. In this paper we overcome such a limitation, by proposing a general algebra which is parametrically adapted to cope with the relational approaches to now-relative data in the literature, i.e., MIN, MAX, NULL and POINT approaches. Besides being general enough to provide a query language for several approaches in the literature, our algebra has been designed in such a way to satisfy several theoretical and practical desiderata: closure with respect to representation languages, correctness with respect to the “consensus” BCDM semantics, reducibility to the standard non-temporal algebra (which involves interoperability with non-temporal relational databases), implementability and efficiency. Indeed, the experimental evaluation we have drawn on our implementation has shown that only a slight overhead is added by our treatment of now-relative data (with respect to an approach in which such data are not present).
In questo articolo viene presentata un'applicazione informatica che esegue automaticamente la... more In questo articolo viene presentata un'applicazione informatica che esegue automaticamente la trascrizione e traslitterazione di un testo in lingua russa. La traslitterazione trasforma il testo scritto in alfabeto cirillico in alfabeto latino, mentre la trascrizione è volta a rispettare il più possibile la pronuncia originaria e indica a un parlante italiano come pronunciare il testo russo. La peculiarità della soluzione proposta risiede nell'uso di un foglio elettronico e delle relative funzioni disponibili, per fornire uno strumento (i) multipiattaforma e (ii) didatticamente valido, in quanto (i) le regole di traslitterazione e trascrizione possono essere adattate ad altre architetture e applicativi e (ii) sono facilmente modificabili da utenti non esperti di informatica. В статье рассматривается компьютерное применение, которое осуществляет автоматически транскрипцию и транслитерацию любого текста на русском языке. Транслитерация перевращает текст написанный кириллицей в ...
Configuration was one of the first tasks successfully approached via AI techniques. However, solv... more Configuration was one of the first tasks successfully approached via AI techniques. However, solving configuration problems can be computationally expensive. In this work, we show that the decomposition of a configuration problem into a set of simpler and mutually independent subproblems can decrease the computational cost of solving it. In particular, we describe a decomposition technique exploiting the compositional structure
ABSTRACT Knowledge-based clinical decision making is one of the most challenging activities of ph... more ABSTRACT Knowledge-based clinical decision making is one of the most challenging activities of physicians. Clinical Practice Guidelines are commonly recognized as a useful tool to help physicians in such activities by encoding the indications provided by evidence ...
Several explanation and interpretation tasks, such as diagnosis, plan recognition and image inter... more Several explanation and interpretation tasks, such as diagnosis, plan recognition and image interpre- tation, can be formalized as abductive and consis- tency reasoning. Some proposals address the prob- lem based on a task-independent representation of a domain which includes an ontology or taxonomy of hypotheses. In this paper we rely on the same type of representation, and we address cost
ABSTRACT In the real world, many phenomena are time related and in the last three decades the dat... more ABSTRACT In the real world, many phenomena are time related and in the last three decades the database community has devoted much work in dealing with “time of facts” in databases. While many approaches incorporating time in the relational model have been already devised, most of them assume that the exact time of facts is known. However, this assumption does not hold in many practical domains, in which temporal indeterminacy of facts occurs. The treatment of valid-time indeterminacy requires in-depth extensions to the current relational approaches. In this paper, we propose a theoretically grounded approach to cope with this issue, overcoming the limitations of related approaches in the literature. In particular, we present a 1NF temporal relational model and propose a new temporal relational algebra to query it. We also formally study the properties of the new data model and algebra, thus granting that our approach is interoperable with pre-existent temporal and non-temporal relational approaches, and is implementable on top of them. Finally, we consider computational complexity, showing that only a limited overhead is added when moving from determinate to indeterminate time.
ABSTRACT Now-related temporal data play an important role in the medical context. Current relatio... more ABSTRACT Now-related temporal data play an important role in the medical context. Current relational temporal database (TDB) approaches are limited since (i) they (implicitly) assume that the span of time occurring between the time when facts change in the world and the time when the changes are recorded in the database is exactly known, and (ii) do not explicitly provide an extended relational algebra to query now-related data. We propose an approach that, widely adopting AI symbolic manipulation techniques, overcomes the above limitations.
Studies in health technology and informatics, 2008
A crucial feature of computerized clinical guidelines (CGs) lies in the fact that they may be use... more A crucial feature of computerized clinical guidelines (CGs) lies in the fact that they may be used not only as conventional documents (as if they were just free text) describing general procedures that users have to follow. In fact, thanks to a description of their actions and control flow in some semiformal representation language, CGs can also take advantage of Computer Science methods and Information Technology infrastructures and techniques, to become executable documents, in the sense that they may support clinical decision making and clinical procedures execution. In order to reach this goal, some advanced planning techniques, originally developed within the Artificial Intelligence (AI) community, may be (at least partially) resorted too, after a proper adaptation to the specific CG needs has been carried out.
Studies in health technology and informatics, 2007
Temporal constraints play a fundamental role in clinical guidelines. For example, temporal indete... more Temporal constraints play a fundamental role in clinical guidelines. For example, temporal indeterminacy, constraints about duration, delays between actions and periodic repetitions of actions are essential in order to cope with clinical therapies. This paper proposes a computer-based approach in order to deal with temporal constraints in clinical guidelines. Specifically, it provides the possibility to represent such constraints and reason with them (i.e., perform inferences in the form of constraint propagation). We first propose a temporal representation formalism and two constraint propagation algorithms operating on it, and then we show how they can be exploited in order to provide clinical guideline systems with different temporal facilities. Our approach offers several advantages: for example, during the guideline acquisition phase, it enables to represent temporal constraints and to check their consistency; during the execution phase, it allows the physician to check the con...
Studies in health technology and informatics, 2007
Representing clinical guidelines is a very complex knowledge-representation task, requiring a lot... more Representing clinical guidelines is a very complex knowledge-representation task, requiring a lot of expertise and efforts. Nevertheless, guideline representations often contain several kinds of errors. Therefore, checking the well-formedness and correctness of a guideline representation is an important task, which can be drastically improved with the adoption of computer programs. In this paper, we discuss the advanced facilities provided by the GLARE system to assist physicians to produce correct representations of clinical guidelines.
Temporal constraints play a fundamental role in clinical guidelines. We sketch a computer-based t... more Temporal constraints play a fundamental role in clinical guidelines. We sketch a computer-based temporal framework to represent temporal information in the guidelines, and to support different forms of inference and query-answering (which, e.g., might help in physician decision making).
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Papers by Luca Anselma