Query Rewriting and Optimization for Ontological Databases

Ontological queries are evaluated against a knowledge base consisting of an extensional database and an ontology (i.e., a set of logical assertions and constraints which derive new intensional knowledge from the extensional database), rather than directly on the extensional database. The evaluation and optimization of such queries is an intriguing new problem for database research. In this paper, we discuss two important aspects of this problem: query rewriting and query optimization. Query rewriting consists of the compilation of an ontological query into an equivalent first-order query against the underlying extensional database. We present a novel query rewriting algorithm for rather general types of ontological constraints which is well-suited for practical implementations. In particular, we show how a conjunctive query against a knowledge base, expressed using linear and sticky existential rules, that is, members of the recently introduced Datalog+/- family of ontology languages, can be compiled into a union of conjunctive queries (UCQ) against the underlying database. Ontological query optimization, in this context, attempts to improve this rewriting process so to produce possibly small and cost-effective UCQ rewritings for an input query.Comment: arXiv admin note: text overlap with arXiv:1312.5914 by other author

Measuring Community Adaptive and Transformative Capacity in the Arctic Context

Adaptive capacity (AC) plays a prominent role in reducing community vulnerability, an essential goal for achieving sustainability. The related concept, transformative capacity (TC), describes a set of tools from the resilience paradigm for making more fundamental system changes. While the literature appears to agree generally on the meaning of AC and TC, operational definitions vary widely in empirical applications. We address measurement of AC and TC in empirical studies of community vulnerability and resilience, with special attention to the problems of arctic communities. We discuss how some challenges follow from ambiguities in the broader vulnerability model within which AC is embedded. Other issues are more technical, such as a confounding of stocks (capacity) with flows (time-specific inputs or outcomes). We view AC and TC as forms of capital, as distinct from flows (i.e., ecosystem services, well-being), and propose a set of sequential steps for measuring the contribution of AC and TC assets to reducing vulnerability. We demonstrate the conceptual application in a comparative analysis of AC in two arctic Alaska communities responding to an increase in the price of fuel. The comparative case study illustrates some key empirical challenges in measuring AC for small arctic communities

empathi: An ontology for Emergency Managing and Planning about Hazard Crisis

In the domain of emergency management during hazard crises, having sufficient situational awareness information is critical. It requires capturing and integrating information from sources such as satellite images, local sensors and social media content generated by local people. A bold obstacle to capturing, representing and integrating such heterogeneous and diverse information is lack of a proper ontology which properly conceptualizes this domain, aggregates and unifies datasets. Thus, in this paper, we introduce empathi ontology which conceptualizes the core concepts concerning with the domain of emergency managing and planning of hazard crises. Although empathi has a coarse-grained view, it considers the necessary concepts and relations being essential in this domain. This ontology is available at https://w3id.org/empathi/

SNOMED CT standard ontology based on the ontology for general medical science

Background: Systematized Nomenclature of Medicine—Clinical Terms (SNOMED CT, hereafter abbreviated SCT) is acomprehensive medical terminology used for standardizing the storage, retrieval, and exchange of electronic healthdata. Some efforts have been made to capture the contents of SCT as Web Ontology Language (OWL), but theseefforts have been hampered by the size and complexity of SCT. Method: Our proposal here is to develop an upper-level ontology and to use it as the basis for defining the termsin SCT in a way that will support quality assurance of SCT, for example, by allowing consistency checks ofdefinitions and the identification and elimination of redundancies in the SCT vocabulary. Our proposed upper-levelSCT ontology (SCTO) is based on the Ontology for General Medical Science (OGMS). Results: The SCTO is implemented in OWL 2, to support automatic inference and consistency checking. Theapproach will allow integration of SCT data with data annotated using Open Biomedical Ontologies (OBO) Foundryontologies, since the use of OGMS will ensure consistency with the Basic Formal Ontology, which is the top-levelontology of the OBO Foundry. Currently, the SCTO contains 304 classes, 28 properties, 2400 axioms, and 1555annotations. It is publicly available through the bioportal athttp://bioportal.bioontology.org/ontologies/SCTO/. Conclusion: The resulting ontology can enhance the semantics of clinical decision support systems and semanticinteroperability among distributed electronic health records. In addition, the populated ontology can be used forthe automation of mobile health applications

Relational Identities and Other-Than-Human Agency in Archaeology

Relational Identities and Other-than-Human Agency in Archaeology explores the benefits and consequences of archaeological theorizing on and interpretation of the social agency of nonhumans as relational beings capable of producing change in the world. The volume cross-examines traditional understanding of agency and personhood, presenting a globally diverse set of case studies that cover a range of cultural, geographical, and historical contexts. Agency (the ability to act) and personhood (the reciprocal qualities of relational beings) have traditionally been strictly assigned to humans. In case studies from Ghana to Australia to the British Isles and Mesoamerica, contributors to this volume demonstrate that objects, animals, locations, and other nonhuman actors also potentially share this ontological status and are capable of instigating events and enacting change. This kind of other-than-human agency is not a one-way transaction of cause to effect but requires an appropriate form of reciprocal engagement indicative of relational personhood, which in these cases, left material traces detectable in the archaeological record. Modern dualist ontologies separating objects from subjects and the animate from the inanimate obscure our understanding of the roles that other-than-human agents played in past societies. Relational Identities and Other-than-Human Agency in Archaeology challenges this essentialist binary perspective. Contributors in this volume show that intersubjective (inherently social) ways of being are a fundamental and indispensable condition of all personhood and move the debate in posthumanist scholarship beyond the polarizing dichotomies of relational versus bounded types of persons. In this way, the book makes a significant contribution to theory and interpretation of personhood and other-than-human agency in archaeology.https://cupola.gettysburg.edu/books/1141/thumbnail.jp

Proceedings ICPW'07: 2nd International Conference on the Pragmatic Web, 22-23 Oct. 2007, Tilburg: NL

Proceedings ICPW'07: 2nd International Conference on the Pragmatic Web, 22-23 Oct. 2007, Tilburg: N

Negotiating Salmon : Ontologies and Resource Mangement in Southwest Alaska

Publisher PD

Negotiating Salmon.

Current environmental crises disclose power hierarchies, such as within the negotiation of how to distribute natural resources. This paper focuses on the importance of acknowledging human-animal relationships and lived realities within the co-management and conservation of resources. The research draws on conflicting ontologies that can be found around salmon conservation in Southwest Alaska, especially around returning king salmon in the Kuskokwim River, which has seen a decline in numbers over the last decade. It illustrates the importance of considering the ontological constitutions of animals as beings, which renders the understanding of how human-animal relations can be maintained throughout crises. Rather than perpetuating the assumption that salmon are ‘natural’ objects, but understood and known differently by indigenous communities, the ontological approach enables us to recognize that salmon are not one entity but constituted beings in enacted worlds.Die aktuellen Umweltkrisen legen Machthierarchien offen, unter anderem in den Verhandlungen um die Verteilung von natürlichen Rohstoffen. Dieser Artikel stellt Mensch-Tier Beziehungen und lokale Lebensrealitäten in den Mittelpunkt von Naturschutzmaßnahmen und der Mitverwaltung von Umweltressourcen. Er analysiert verschiedene Ontologien, die mit verstärkten Maßnahmen zum Schutz von Wildlachs im Südwesten Alaskas sichtbar wurden. Der Fokus liegt insbesondere auf den Königslachsen, die zum laichen in den Kuskokwim Fluss zurückkehren, und die im letzten Jahrzehnt fallende Bestandszahlen aufwiesen. Besondere Beachtung gilt dabei der ontologischen Konstitution der Tiere. Anstatt Lachs als ein universelles, wenn auch unterschiedlich verstandenes und kulturell gedeutetes, Naturobjekt darzustellen, möchte dieser Artikel den ontologischen Ansatz dazu nutzen, um dieses Tier als konstituiertes Lebewesen in erlebten Welten zu verstehen.Peer Reviewe