Learning SHACL Shapes from Knowledge Graphs

Total Page:16

File Type:pdf, Size:1020Kb

Learning SHACL Shapes from Knowledge Graphs Semantic Web 0 (0) 1 1 IOS Press 1 1 2 2 3 3 4 Learning SHACL Shapes from Knowledge 4 5 5 6 Graphs 6 7 7 8 Pouya Ghiasnezhad Omran a,*, Kerry Taylor a Sergio Rodriguez Mendez a and Armin Haller a 8 9 a School of Computing, The Australian National University , ACT, Australia 9 10 E-mails: [email protected], [email protected], [email protected], 10 11 [email protected] 11 12 12 13 13 14 14 15 15 16 Abstract. Knowledge Graphs (KGs) have proliferated on the Web since the introduction of knowledge panels to Google search 16 17 in 2012. KGs are large data-first graph databases with weak inference rules and weakly-constraining data schemes. SHACL, 17 18 the Shapes Constraint Language, is a W3C recommendation for expressing constraints on graph data as shapes. SHACL shapes 18 19 serve to validate a KG, to underpin manual KG editing tasks and to offer insight into KG structure. 19 We introduce Inverse Open Path (IOP) rules, a predicate logic formalism which presents specific shapes in the form of paths 20 20 over connected entities. Although IOP rules express simple shape patterns, they can be augmented with minimum cardinality 21 21 constraints and also used as a building block for more complex shapes, such as trees and other rule patterns. We define quality 22 measures for IOP rules and propose a novel method to learn high-quality rules from KGs. We show how to build high-quality 22 23 tree shapes from the IOP rules. Our learning method, SHACLEARNER, is adapted from a state-of-the-art embedding-based open 23 24 path rule learner (OPRL). 24 25 We evaluate SHACLEARNER on some real-world massive KGs, including YAGO2s (4M facts), DBpedia 3.8 (11M facts), 25 26 and Wikidata (8M facts). The experiments show SHACLEARNER can learn informative and intuitive shapes from massive KGs 26 27 effectively. Our experiments show the learned shapes are diverse in both structural features such as depth and width, and in 27 28 quality measures. 28 29 29 Keywords: SHACL Shape Learning, Shapes Constraint Language, Knowledge Graph, Inverse Open Path Rule 30 30 31 31 32 32 33 33 1. Introduction while less for others (e.g. opera singers). Even for the 34 34 same type of entity, for example, computer scientists, 35 35 While public knowledge graphs (KGs) became pop- there are different depths of detail depending on the 36 36 ular with the development of DBpedia [1] and Yago [2] country of origin of the scientist. 37 37 more than a decade ago, interest in enterprise knowl- 38 However, the power of KGs comes from their data- 38 edge graphs [3] has only taken off since the inclu- 39 first approach, enabling contributors to extend a KG 39 sion of knowledge panels on the Google Search en- 40 in a relatively arbitrary manner. By contrast, a rela- 40 gine, driven by its internal knowledge graph, in 2012. 41 tional database typically employs not-null and other 41 Although these KGs are massive and diverse, they are 42 constraints that require some attributes to be instanti- 42 typically incomplete. Regardless of the method that is 43 ated at all times. Large KGs are typically populated 43 44 used to build a KG (e.g. collaboratively vs individually, by automatic and semi-automatic methods using non- 44 45 manually vs automatically), it will be incomplete be- structured sources (e.g. Wikipedia) that are prone to 45 46 cause of the evolving nature of human knowledge, cul- errors of omission and commission. 46 47 tural bias [4] and resource constraints. Consider Wiki- SHACL[6] was formally recommended by the W3C 47 48 data [5], for example, where there is more complete in 2017 to express constraints on a KG as shapes. For 48 49 information for some types of entities (e.g. pop stars), example, SHACL can be used to express that a person 49 50 needs to have a name, birth date, and place of birth, 50 51 *Corresponding author. E-mail: [email protected]. and that these attributes have particular types: a string; 51 1570-0844/0-1900/$35.00 © 0 – IOS Press and the authors. All rights reserved 2 Ghiasnezhad Omran et al. / SHACLearner 1 a date; a location. The shapes are used to guide the propose a predicate calculus formalism in which rules 1 2 population of a KG, although they are not necessar- have one body atom and a chain of conjunctive atoms 2 3 ily enforced. Typically, SHACL shapes are manually- in the head with a specific variable binding pattern. 3 4 specified and the methods to do this are well-studied. Since these rules are an inverse version of open path 4 5 However, as for multidimensional relational database rules [13], we call them inverse open path (IOP) rules. 5 6 schemes [7], shapes could, in principle, be inferred To learn IOP rules we adapt an embedding-based open 6 7 from KG data. As frequent patterns, the shapes charac- path rule learner, OPRL [13]. We define quality mea- 7 8 terise a KG and can be used for subsequent data clean- sures to express the validity of IOP rules in a KG. 8 9 ing or ongoing data entry. There is scant previous re- SHACLEARNER uses the mined IOP rules to subse- 9 10 search on this topic [8]. quently discover more complex tree shapes. Each IOP 10 11 While basic SHACL [6] and its advanced fea- rule or tree is a SHACL shape, in the sense that it 11 12 tures [9] allows the modelling of diverse shapes in- can be syntactically rewritten in SHACL. Our mined 12 13 cluding rules and constraints, most of these shapes shapes are augmented with a novel numerical confi- 13 14 are previously well known as expressed by alterna- dence measure to express the strength of evidence in 14 15 tive formalisms, including closed rules [10], trees, the KG for each shape. 15 16 existential rules [11], and graph functional depen- 16 17 dencies [12]. We claim that the common underlying 17 18 form of all these shapes is the path, over which ad- 2. Preliminaries 18 19 ditional constraints induce the various versions. For 19 20 example in DBpedia we discover the following path, An entity e is an identifier for an object such as 20 21 < dbo : type > _ < db : S ong > (x) !< dbo : a place or a person. A fact (also known as a link) 21 22 album > (x; y)^ < dbo : recordLabel > (y; z): which is an RDF triple (e; P; e0), written here as as P(e; e0), 22 23 expresses that if an entity x is a song, then x is in an meaning that the subject entity e is related to an ob- 23 24 album y which has a record label z. ject entity e0 via the binary predicate (also known as 24 25 Since the satisfaction of a less-constrained shape is a property), P. In addition, we admit unary predicates 25 26 a necessary condition for satisfaction of a more com- of the form P(e), also written as the fact P(e; e). We 26 27 plex shape (but not a sufficient condition), in this pa- model unary predicates as self-loops to make the unary 27 28 per we focus on learning paths, the least constrained predicate act as the label of an link in the graph, just 28 29 shape for our purposes. Paths can serve as the basis for as for binary predicates. Unary predicates may, but 29 30 more complex shapes. We also investigate the process are not limited to, represent class assertions expressed 30 31 of constructing one kind of more complex shape, that in an RDF triple as (e; rdf:type; P) where P is a 31 32 is a tree, out of paths. For example, we discover a tree class or a datatype. A knowledge graph (KG) is a pair 32 33 about an entity which has song as its type as we show K = (E; F), where E is a set of entities and F is a set 33 34 in Fig. 1. In a KG context, the tree suggests that if we of facts and all the entities occurring in F also occur in 34 35 have an entity of type song in the KG, then we would E. 35 36 expect to have the associated facts as well. 36 37 2.1. Closed-Path Rules 37 38 38 39 KG rule learning systems employ various rule lan- 39 40 guages to express rules. RLVLR [14] and SCALEKB 40 41 [15] use so-called closed path (CP) rules that are a kind 41 42 of closed rule as they have no free variables. Each con- 42 43 sists of a head at the front of the implication arrow and 43 44 a body at the tail. We say the rule is about the predicate 44 45 of the head. The rule forms a closed path, or single un- 45 46 broken loop of links between the variables. It has the 46 47 following general form. 47 48 Fig. 1. A tree shape for the Song concept from DBpedia. 48 49 49 Pt(x; y) P1(x; z1)^P2(z1; z2)^:::^Pn(zn−1; y): 50 In this paper, we present a system, SHACLEARNER, 50 51 that mines shapes from KG data. For this purpose we (1) 51 Ghiasnezhad Omran et al.
Recommended publications
  • V a Lida T in G R D F Da
    Series ISSN: 2160-4711 LABRA GAYO • ET AL GAYO LABRA Series Editors: Ying Ding, Indiana University Paul Groth, Elsevier Labs Validating RDF Data Jose Emilio Labra Gayo, University of Oviedo Eric Prud’hommeaux, W3C/MIT and Micelio Iovka Boneva, University of Lille Dimitris Kontokostas, University of Leipzig VALIDATING RDF DATA This book describes two technologies for RDF validation: Shape Expressions (ShEx) and Shapes Constraint Language (SHACL), the rationales for their designs, a comparison of the two, and some example applications. RDF and Linked Data have broad applicability across many fields, from aircraft manufacturing to zoology. Requirements for detecting bad data differ across communities, fields, and tasks, but nearly all involve some form of data validation. This book introduces data validation and describes its practical use in day-to-day data exchange. The Semantic Web offers a bold, new take on how to organize, distribute, index, and share data. Using Web addresses (URIs) as identifiers for data elements enables the construction of distributed databases on a global scale. Like the Web, the Semantic Web is heralded as an information revolution, and also like the Web, it is encumbered by data quality issues. The quality of Semantic Web data is compromised by the lack of resources for data curation, for maintenance, and for developing globally applicable data models. At the enterprise scale, these problems have conventional solutions. Master data management provides an enterprise-wide vocabulary, while constraint languages capture and enforce data structures. Filling a need long recognized by Semantic Web users, shapes languages provide models and vocabularies for expressing such structural constraints.
    [Show full text]
  • Deciding SHACL Shape Containment Through Description Logics Reasoning
    Deciding SHACL Shape Containment through Description Logics Reasoning Martin Leinberger1, Philipp Seifer2, Tjitze Rienstra1, Ralf Lämmel2, and Steffen Staab3;4 1 Inst. for Web Science and Technologies, University of Koblenz-Landau, Germany 2 The Software Languages Team, University of Koblenz-Landau, Germany 3 Institute for Parallel and Distributed Systems, University of Stuttgart, Germany 4 Web and Internet Science Research Group, University of Southampton, England Abstract. The Shapes Constraint Language (SHACL) allows for for- malizing constraints over RDF data graphs. A shape groups a set of constraints that may be fulfilled by nodes in the RDF graph. We investi- gate the problem of containment between SHACL shapes. One shape is contained in a second shape if every graph node meeting the constraints of the first shape also meets the constraints of the second. Todecide shape containment, we map SHACL shape graphs into description logic axioms such that shape containment can be answered by description logic reasoning. We identify several, increasingly tight syntactic restrictions of SHACL for which this approach becomes sound and complete. 1 Introduction RDF has been designed as a flexible, semi-structured data format. To ensure data quality and to allow for restricting its large flexibility in specific domains, the W3C has standardized the Shapes Constraint Language (SHACL)5. A set of SHACL shapes are represented in a shape graph. A shape graph represents constraints that only a subset of all possible RDF data graphs conform to. A SHACL processor may validate whether a given RDF data graph conforms to a given SHACL shape graph. A shape graph and a data graph that act as a running example are pre- sented in Fig.
    [Show full text]
  • Using Rule-Based Reasoning for RDF Validation
    Using Rule-Based Reasoning for RDF Validation Dörthe Arndt, Ben De Meester, Anastasia Dimou, Ruben Verborgh, and Erik Mannens Ghent University - imec - IDLab Sint-Pietersnieuwstraat 41, B-9000 Ghent, Belgium [email protected] Abstract. The success of the Semantic Web highly depends on its in- gredients. If we want to fully realize the vision of a machine-readable Web, it is crucial that Linked Data are actually useful for machines con- suming them. On this background it is not surprising that (Linked) Data validation is an ongoing research topic in the community. However, most approaches so far either do not consider reasoning, and thereby miss the chance of detecting implicit constraint violations, or they base them- selves on a combination of dierent formalisms, eg Description Logics combined with SPARQL. In this paper, we propose using Rule-Based Web Logics for RDF validation focusing on the concepts needed to sup- port the most common validation constraints, such as Scoped Negation As Failure (SNAF), and the predicates dened in the Rule Interchange Format (RIF). We prove the feasibility of the approach by providing an implementation in Notation3 Logic. As such, we show that rule logic can cover both validation and reasoning if it is expressive enough. Keywords: N3, RDF Validation, Rule-Based Reasoning 1 Introduction The amount of publicly available Linked Open Data (LOD) sets is constantly growing1, however, the diversity of the data employed in applications is mostly very limited: only a handful of RDF data is used frequently [27]. One of the reasons for this is that the datasets' quality and consistency varies signicantly, ranging from expensively curated to relatively low quality data [33], and thus need to be validated carefully before use.
    [Show full text]
  • Bibliography of Erik Wilde
    dretbiblio dretbiblio Erik Wilde's Bibliography References [1] AFIPS Fall Joint Computer Conference, San Francisco, California, December 1968. [2] Seventeenth IEEE Conference on Computer Communication Networks, Washington, D.C., 1978. [3] ACM SIGACT-SIGMOD Symposium on Principles of Database Systems, Los Angeles, Cal- ifornia, March 1982. ACM Press. [4] First Conference on Computer-Supported Cooperative Work, 1986. [5] 1987 ACM Conference on Hypertext, Chapel Hill, North Carolina, November 1987. ACM Press. [6] 18th IEEE International Symposium on Fault-Tolerant Computing, Tokyo, Japan, 1988. IEEE Computer Society Press. [7] Conference on Computer-Supported Cooperative Work, Portland, Oregon, 1988. ACM Press. [8] Conference on Office Information Systems, Palo Alto, California, March 1988. [9] 1989 ACM Conference on Hypertext, Pittsburgh, Pennsylvania, November 1989. ACM Press. [10] UNIX | The Legend Evolves. Summer 1990 UKUUG Conference, Buntingford, UK, 1990. UKUUG. [11] Fourth ACM Symposium on User Interface Software and Technology, Hilton Head, South Carolina, November 1991. [12] GLOBECOM'91 Conference, Phoenix, Arizona, 1991. IEEE Computer Society Press. [13] IEEE INFOCOM '91 Conference on Computer Communications, Bal Harbour, Florida, 1991. IEEE Computer Society Press. [14] IEEE International Conference on Communications, Denver, Colorado, June 1991. [15] International Workshop on CSCW, Berlin, Germany, April 1991. [16] Third ACM Conference on Hypertext, San Antonio, Texas, December 1991. ACM Press. [17] 11th Symposium on Reliable Distributed Systems, Houston, Texas, 1992. IEEE Computer Society Press. [18] 3rd Joint European Networking Conference, Innsbruck, Austria, May 1992. [19] Fourth ACM Conference on Hypertext, Milano, Italy, November 1992. ACM Press. [20] GLOBECOM'92 Conference, Orlando, Florida, December 1992. IEEE Computer Society Press. http://github.com/dret/biblio (August 29, 2018) 1 dretbiblio [21] IEEE INFOCOM '92 Conference on Computer Communications, Florence, Italy, 1992.
    [Show full text]
  • SHACL Satisfiability and Containment
    SHACL Satisfiability and Containment Paolo Pareti1 , George Konstantinidis1 , Fabio Mogavero2 , and Timothy J. Norman1 1 University of Southampton, Southampton, United Kingdom {pp1v17,g.konstantinidis,t.j.norman}@soton.ac.uk 2 Università degli Studi di Napoli Federico II, Napoli, Italy [email protected] Abstract. The Shapes Constraint Language (SHACL) is a recent W3C recom- mendation language for validating RDF data. Specifically, SHACL documents are collections of constraints that enforce particular shapes on an RDF graph. Previous work on the topic has provided theoretical and practical results for the validation problem, but did not consider the standard decision problems of satisfiability and containment, which are crucial for verifying the feasibility of the constraints and important for design and optimization purposes. In this paper, we undertake a thorough study of different features of non-recursive SHACL by providing a translation to a new first-order language, called SCL, that precisely captures the semantics of SHACL w.r.t. satisfiability and containment. We study the interaction of SHACL features in this logic and provide the detailed map of decidability and complexity results of the aforementioned decision problems for different SHACL sublanguages. Notably, we prove that both problems are undecidable for the full language, but we present decidable combinations of interesting features. 1 Introduction The Shapes Constraint Language (SHACL) has been recently introduced as a W3C recommendation language for the validation of RDF graphs, and it has already been adopted by mainstream tools and triplestores. A SHACL document is a collection of shapes which define particular constraints and specify which nodes in a graph should be validated against these constraints.
    [Show full text]
  • Using Rule-Based Reasoning for RDF Validation
    View metadata, citation and similar papers at core.ac.uk brought to you by CORE provided by Ghent University Academic Bibliography Using Rule-Based Reasoning for RDF Validation Dörthe Arndt, Ben De Meester, Anastasia Dimou, Ruben Verborgh, and Erik Mannens Ghent University - imec - IDLab Sint-Pietersnieuwstraat 41, B-9000 Ghent, Belgium [email protected] Abstract. The success of the Semantic Web highly depends on its in- gredients. If we want to fully realize the vision of a machine-readable Web, it is crucial that Linked Data are actually useful for machines con- suming them. On this background it is not surprising that (Linked) Data validation is an ongoing research topic in the community. However, most approaches so far either do not consider reasoning, and thereby miss the chance of detecting implicit constraint violations, or they base them- selves on a combination of dierent formalisms, eg Description Logics combined with SPARQL. In this paper, we propose using Rule-Based Web Logics for RDF validation focusing on the concepts needed to sup- port the most common validation constraints, such as Scoped Negation As Failure (SNAF), and the predicates dened in the Rule Interchange Format (RIF). We prove the feasibility of the approach by providing an implementation in Notation3 Logic. As such, we show that rule logic can cover both validation and reasoning if it is expressive enough. Keywords: N3, RDF Validation, Rule-Based Reasoning 1 Introduction The amount of publicly available Linked Open Data (LOD) sets is constantly growing1, however, the diversity of the data employed in applications is mostly very limited: only a handful of RDF data is used frequently [27].
    [Show full text]
  • Finding Non-Compliances with Declarative Process Constraints Through Semantic Technologies
    Finding Non-compliances with Declarative Process Constraints through Semantic Technologies Claudio Di Ciccio2, Fajar J. Ekaputra1, Alessio Cecconi2, Andreas Ekelhart1, Elmar Kiesling1 1 TU Wien, Favoritenstrasse 9-11, 1040 Vienna, Austria, [email protected] 2 WU Vienna, Welthandelsplatz 1, 1020 Vienna, Austria fclaudio.di.ciccio,[email protected] Abstract. Business process compliance checking enables organisations to assess whether their processes fulfil a given set of constraints, such as regulations, laws, or guidelines. Whilst many process analysts still rely on ad-hoc, often handcrafted per- case checks, a variety of constraint languages and approaches have been developed in recent years to provide automated compliance checking. A salient example is DE- CLARE, a well-established declarative process specification language based on tem- poral logics. DECLARE specifies the behaviour of processes through temporal rules that constrain the execution of tasks. So far, however, automated compliance check- ing approaches typically report compliance only at the aggregate level, using binary evaluations of constraints on execution traces. Consequently, their results lack gran- ular information on violations and their context, which hampers auditability of pro- cess data for analytic and forensic purposes. To address this challenge, we propose a novel approach that leverages semantic technologies for compliance checking. Our approach proceeds in two stages. First, we translate DECLARE templates into state- ments in SHACL, a graph-based constraint language. Then, we evaluate the resulting constraints on the graph-based, semantic representation of process execution logs. We demonstrate the feasibility of our approach by testing its implementation on real- world event logs. Finally, we discuss its implications and future research directions.
    [Show full text]
  • Integrating Semantic Web Technologies and ASP for Product Configuration
    Integrating Semantic Web Technologies and ASP for Product Configuration Stefan Bischof1 and Gottfried Schenner1 and Simon Steyskal1 and Richard Taupe1,2 Abstract. Currently there is no single dominating technol- own proprietary specification language. Also in the product ogy for building product configurator systems. While research configuration community there is currently no standard way often focuses on a single technology/paradigm, building an to specify product configuration problems although the topic industrial-scale product configurator system will almost al- of ontologies and product configuration is over 20 years old ways require the combination of various technologies for dif- (cf. [21]) and pre-dates the Semantic Web. ferent aspects of the system (knowledge representation, rea- In Section2 we describe the technologies used for this pa- soning, solving, user interface, etc.) This paper demonstrates per. In Section3 we show how to define a product configurator how to build such a hybrid system and how to integrate var- knowledge base with RDF and SHACL, that allows checking ious technologies and leverage their respective strengths. of constraints and interactive solving. Due to the increasing popularity of the industrial knowledge For solving product configuration problems, RDF and graph we utilize Semantic Web technologies (RDF, OWL and SHACL are combined with Answer Set Programming in Sec- the Shapes Constraint Language (SHACL)) for knowledge tion4. In Section5 we illustrate how reasoning with OWL representation and integrate it with Answer Set Programming can help to integrate the product configuration solutions into (ASP), a well-established solving paradigm for product con- the knowledge graph and facilitate reuse of ontologies. figuration.
    [Show full text]
  • Linked Data Schemata: Fixing Unsound Foundations
    Linked data schemata: fixing unsound foundations Editor(s): Amrapali Zaveri, Stanford University, USA; Dimitris Kontokostas, Universität Leipzig, Germany; Sebastian Hellmann, Universität Leipzig, Germany; Jürgen Umbrich, Wirtschaftsuniversität Wien, Austria Solicited review(s): Mathieu d’Aquin, The Open University, UK; Peter F. Patel-Schneider, Nuance Communications, USA; John McCrae, Insight Centre for Data Analytics, Ireland; One anonymous reviewer Kevin Chekov Feeney, Gavin Mendel Gleason, and Rob Brennan Knowledge and Data Engineering Group & ADAPT Centre, School of Computer Science & Statistics, Trinity College Dublin, Ireland Corresponding author’s e-mail: [email protected] Abstract. This paper describes our tools and method for an evaluation of the practical and logical implications of combining common linked data vocabularies into a single local logical model for the purpose of reasoning or performing quality evalua- tions. These vocabularies need to be unified to form a combined model because they reference or reuse terms from other linked data vocabularies and thus the definitions of those terms must be imported. We found that strong interdependencies between vocabularies are common and that a significant number of logical and practical problems make this model unification inconsistent. In addition to identifying problems, this paper suggests a set of recommendations for linked data ontology design best practice. Finally we make some suggestions for improving OWL’s support for distributed authoring and ontology reuse. Keywords: Linked Data, Reasoning, Data Quality 1. Introduction In order to validate any dataset which uses the adms:Asset term we must combine the adms ontolo- One of the central tenets of the linked data move- gy and the dcat ontology in order to ensure that ment is the reuse of terms from existing well-known dcat:Dataset is a valid class.
    [Show full text]
  • Trav-SHACL: Efficiently Validating Networks of SHACL Constraints
    Trav-SHACL: Efficiently Validating Networks of SHACL Constraints M´onicaFiguera1,2, Philipp D. Rohde1,3, and Maria-Esther Vidal1,3 1L3S Research Center, Leibniz University of Hannover, Germany 2University of Bonn, Germany 3TIB Leibniz Information Centre for Science and Technology, Hannover, Germany [email protected], fphilipp.rohde,[email protected] Abstract Knowledge graphs have emerged as expressive data structures for Web data. Knowledge graph potential and the demand for ecosystems to facili- tate their creation, curation, and understanding, is testified in diverse domains, e.g., biomedicine. The Shapes Constraint Language (SHACL) is the W3C rec- ommendation language for integrity constraints over RDF knowledge graphs. Enabling quality assements of knowledge graphs, SHACL is rapidly gaining attention in real-world scenarios. SHACL models integrity constraints as a net- work of shapes, where a shape contains the constraints to be fullfiled by the same entities. The validation of a SHACL shape schema can face the issue of tractability during validation. To facilitate full adoption, efficient computational methods are required. We present Trav-SHACL, a SHACL engine capable of planning the traversal and execution of a shape schema in a way that invalid entities are detected early and needless validations are minimized. Trav-SHACL reorders the shapes in a shape schema for efficient validation and rewrites target and constraint queries for the fast detection of invalid entities. Trav-SHACL is empirically evaluated on 27 testbeds executed against knowledge graphs of up to 34M triples. Our experimental results suggest that Trav-SHACL exhibits high performance gradually and reduces validation time by a factor of up to arXiv:2101.07136v1 [cs.DB] 18 Jan 2021 28.93 compared to the state of the art.
    [Show full text]
  • OSLC Core Version 3.0. Part 8: Constraints Project Specification 01 17 September 2020
    Standards Track Work Product OSLC Core Version 3.0. Part 8: Constraints Project Specification 01 17 September 2020 This stage: https://docs.oasis-open-projects.org/oslc-op/core/v3.0/ps01/core-shapes.html (Authoritative) https://docs.oasis-open-projects.org/oslc-op/core/v3.0/ps01/core-shapes.pdf Previous stage: N/A Latest stage: https://docs.oasis-open-projects.org/oslc-op/core/v3.0/core-shapes.html (Authoritative) https://docs.oasis-open-projects.org/oslc-op/core/v3.0/core-shapes.pdf Latest version: https://open-services.net/spec/core/latest Latest editor's draft: https://open-services.net/spec/core/latest-draft Open Project: OASIS Open Services for Lifecycle Collaboration (OSLC) OP Project Chairs: Jim Amsden ([email protected]), IBM Andrii Berezovskyi ([email protected]), KTH Editor: Jim Amsden ([email protected]), IBM Additional components: This specification is one component of a Work Product that also includes: OSLC Core Version 3.0. Part 1: Overview. oslc-core.html OSLC Core Version 3.0. Part 2: Discovery. discovery.html OSLC Core Version 3.0. Part 3: Resource Preview. resource-preview.html OSLC Core Version 3.0. Part 4: Delegated Dialogs. dialogs.html OSLC Core Version 3.0. Part 5: Attachments. attachments.html OSLC Core Version 3.0. Part 6: Resource Shape. resource-shape.html OSLC Core Version 3.0. Part 7: Vocabulary. core-vocab.html core-shapes Copyright © OASIS Open 2020. All Rights Reserved. 17 September 2020 - Page 1 of 19 Standards Track Work Product OSLC Core Version 3.0. Part 8: Constraints (this document).
    [Show full text]
  • Healing the Fragmentation to Realise the Full Potential of The
    HealingHealing thethe fragmentationfragmentation toto realiserealise thethe fullfull potentialpotential of thethe IoTIoT Dr.Dr. DaveDave Raggett,Raggett, W3C/ERCIMW3C/ERCIM email:email: [email protected]@w3.org 2525 JuneJune 20202020 ThisThis talktalk isis supportedsupported byby thethe CreateCreate--IoTIoT CoordinationCoordination andand SupportSupport ActionAction withwith fundingfunding fromfrom thethe EuropeanEuropean CommissionCommission Investments in IoT are at risk! Eric Siow, Director, Open Web Platform Standards and Ecosystem Strategies at Intel: • IoT is a little over 10 years old • Hype has been much greater than present reality • IoT is “biting off more that it can chew” • Trying to address too many markets • Involves too many and mostly uncoordinated SDOs and SIGs 2/14 Key IoT Challenges Facing Smart Cities • Lack of coalescence around a set of complementary standards • Hinders scalability, interoperability and evolution • Need to simplify: prioritise and define requirements • Regional regulatory differences adding to the confusion • Diverse requirements impede scalability of the market • Need regulatory agencies to participate and help with standardisation requirements • Lack of interoperability wastes up to 40% of IoT value1 • Cities and technology partners may waste up to $321 billion by 20252 1. https://www.mckinsey.com/business-functions/digital-mckinsey/our-insights/the-internet-of-things-the-value-of-digitizing-the-physical-world 2. https://machinaresearch.com/news/smart-cities-could-waste-usd341-billion-by-2025-on-non-standardized-iot-deployments/
    [Show full text]