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ShEx
Shape Expressions (ShEx) is a data modelling language for validating and describing a Resource Description Framework (RDF). It was proposed at the 2012 RDF Validation Workshop as a high-level, concise language for RDF validation. The shapes can be defined in a human-friendly compact syntax called ShExC or using any RDF serialization formats like JSON-LD or Turtle. ShEx expressions can be used both to describe RDF and to automatically check the conformance of RDF data. The syntax of ShEx is similar to Turtle and SPARQL while the semantics is inspired by regular expression languages like RelaxNG. Example PREFIX : PREFIX schema: PREFIX xsd: :Person The previous example declares that nodes conforming to shape Person must have one property schema:name with a string value and zero or more properties schema:knows whose values must conform with shape Person. Implementations shex.js JavaScript shaclex Scala library with support for Jena (framework) and RDF4J PyShEx ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
SHACL
Shapes Constraint Language (SHACL) is a World Wide Web Consortium (W3C) standard language for describing Resource Description Framework (RDF) graphs. SHACL has been designed to enhance the semantic and technical interoperability layers of ontologies expressed as RDF graphs. SHACL models are defined in terms of constraints on the content, structure and meaning of a graph. SHACL is a highly expressive language. Among others, it includes features to express conditions that constrain the number of values that a property may have, the type of such values, numeric ranges, string matching patterns, and logical combinations of such constraints. SHACL also includes an extension mechanism to express more complex conditions in languages such as SPARQL and JavaScript. SHACL Rules add inferencing capabilities to SHACL, allowing users to define what new statements can be inferred from existing (asserted) statements. The growing adoption of SHACL may influence the future of linked data. Termin ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Resource Description Framework
The Resource Description Framework (RDF) is a World Wide Web Consortium (W3C) standard originally designed as a data model for metadata. It has come to be used as a general method for description and exchange of graph data. RDF provides a variety of syntax notations and data serialization formats with Turtle (Terse RDF Triple Language) currently being the most widely used notation. RDF is a directed graph composed of triple statements. An RDF graph statement is represented by: 1) a node for the subject, 2) an arc that goes from a subject to an object for the predicate, and 3) a node for the object. Each of the three parts of the statement can be identified by a URI. An object can also be a literal value. This simple, flexible data model has a lot of expressive power to represent complex situations, relationships, and other things of interest, while also being appropriately abstract. RDF was adopted as a W3C recommendation in 1999. The RDF 1.0 specification was published in 2004, th ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Wikidata
Wikidata is a collaboratively edited multilingual knowledge graph hosted by the Wikimedia Foundation. It is a common source of open data that Wikimedia projects such as Wikipedia, and anyone else, can use under the CC0 public domain license. Wikidata is a wiki powered by the software MediaWiki, and is also powered by the set of knowledge graph MediaWiki extensions known as Wikibase. Concept Wikidata is a document-oriented database, focused on items, which represent any kind of topic, concept, or object. Each item is allocated a unique, persistent identifier, a positive integer prefixed with the upper-case letter Q, known as a "QID". This enables the basic information required to identify the topic that the item covers to be translated without favouring any language. Examples of items include , , , , and . Item labels need not be unique. For example, there are two items named "Elvis Presley": , which represents the American singer and actor, and , which represents his s ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Data Validation
In computer science, data validation is the process of ensuring data has undergone data cleansing to ensure they have data quality, that is, that they are both correct and useful. It uses routines, often called "validation rules", "validation constraints", or "check routines", that check for correctness, meaningfulness, and security of data that are input to the system. The rules may be implemented through the automated facilities of a data dictionary, or by the inclusion of explicit application program validation logic of the computer and its application. This is distinct from formal verification, which attempts to prove or disprove the correctness of algorithms for implementing a specification or property. Overview Data validation is intended to provide certain well-defined guarantees for fitness and consistency of data in an application or automated system. Data validation rules can be defined and designed using various methodologies, and be deployed in various contexts. Thei ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Jena (framework)
Apache Jena is an open source Semantic Web framework for Java. It provides an API to extract data from and write to RDF graphs. The graphs are represented as an abstract "model". A model can be sourced with data from files, databases, URLs or a combination of these. A model can also be queried through SPARQL 1.1. Jena is similar to RDF4J (formerly OpenRDF Sesame); though, unlike RDF4J, Jena provides support for OWL (Web Ontology Language). The framework has various internal reasoners and the Pellet reasoner (an open source Java OWL-DL reasoner) can be set up to work in Jena. Jena supports serialisation of RDF graphs to: *a relational database *RDF/XML *Turtle * TriG *Notation 3 *JSON-LD Versions After Apache integration Jena was integrated as a project under the umbrella of The Apache Software Foundation in April 2012, after having been in the Apache Incubator since November 2010. Before Apache integration Jena was created by HP Labs and was on SourceForge since 2001, and ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Declarative Programming Languages
Declarative may refer to: * Declarative learning, acquiring information that one can speak about * Declarative memory, one of two types of long term human memory * Declarative programming, a computer programming paradigm * Declarative sentence, a type of sentence that makes a statement * Declarative mood A realis mood (abbreviated ) is a grammatical mood which is used principally to indicate that something is a statement of fact; in other words, to express what the speaker considers to be a known state of affairs, as in declarative sentences. Mos ..., a grammatical verb form used in declarative sentences See also * Declaration (other) {{disamb ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Data Modeling Languages
In the pursuit of knowledge, data (; ) is a collection of discrete values that convey information, describing quantity, quality, fact, statistics, other basic units of meaning, or simply sequences of symbols that may be further interpreted. A datum is an individual value in a collection of data. Data is usually organized into structures such as tables that provide additional context and meaning, and which may themselves be used as data in larger structures. Data may be used as variables in a computational process. Data may represent abstract ideas or concrete measurements. Data is commonly used in scientific research, economics, and in virtually every other form of human organizational activity. Examples of data sets include price indices (such as consumer price index), unemployment rates, literacy rates, and census data. In this context, data represents the raw facts and figures which can be used in such a manner in order to capture the useful information out of it. Da ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
XML Schema
An XML schema is a description of a type of Extensible Markup Language, XML document, typically expressed in terms of constraints on the structure and content of documents of that type, above and beyond the basic syntactical constraints imposed by XML itself. These constraints are generally expressed using some combination of grammatical rules governing the order of elements, Boolean predicates that the content must satisfy, data types governing the content of elements and attributes, and more specialized rules such as uniqueness quantification, uniqueness and referential integrity constraints. There are languages developed specifically to express XML schemas. The document type definition (DTD) language, which is native to the XML specification, is a schema language that is of relatively limited capability, but that also has other uses in XML aside from the expression of schemas. Two more expressive XML schema languages in widespread use are XML Schema (W3C), XML Schema (with a c ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
RDF4J
Eclipse RDF4J (formerly OpenRDF Sesame) is an open-source framework for storing, querying, and analysing RDF data. It was created by the Dutch software company Aduna as part of "On-To-Knowledge", a semantic web project that ran from 1999 to 2002. It contains implementations of an in-memory triplestore and an on-disk triplestore, along with two separate Servlet packages that can be used to manage and provide access to these triplestores, on a permanent server. The RDF4J Rio (RDF Input/Output) package contains a simple API for Java-based RDF parsers and writers. Parsers and writers for popular RDF serialisations are distributed along with RDF4J, and users can easily extend the list by putting their parsers and writers on the Java classpath when running their application. RDF4J supports two query languages: SPARQL and SeRQL. RDF4J's RDF database API differs from comparable solutions in that it offers a stackable interface through which functionality can be added, and the storage e ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Serialization
In computing, serialization (or serialisation) is the process of translating a data structure or object state into a format that can be stored (e.g. files in secondary storage devices, data buffers in primary storage devices) or transmitted (e.g. data streams over computer networks) and reconstructed later (possibly in a different computer environment). When the resulting series of bits is reread according to the serialization format, it can be used to create a semantically identical clone of the original object. For many complex objects, such as those that make extensive use of references, this process is not straightforward. Serialization of object-oriented objects does not include any of their associated methods with which they were previously linked. This process of serializing an object is also called marshalling an object in some situations. The opposite operation, extracting a data structure from a series of bytes, is deserialization, (also called unserialization or un ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
JSON-LD
JSON-LD (JavaScript Object Notation for Linked Data) is a method of encoding linked data using JSON. One goal for JSON-LD was to require as little effort as possible from developers to transform their existing JSON to JSON-LD. JSON-LD allows data to be serialized in a way that is similar to traditional JSON. It was initially developed by the JSON for Linking Data Community Group before being transferred to the RDF Working Group for review, improvement, and standardization, and is currently maintained by the JSON-LD Working Group. JSON-LD is a World Wide Web Consortium Recommendation. Design JSON-LD is designed around the concept of a "context" to provide additional mappings from JSON to an RDF model. The context links object properties in a JSON document to concepts in an ontology. In order to map the JSON-LD syntax to RDF, JSON-LD allows values to be coerced to a specified type or to be tagged with a language. A context can be embedded directly in a JSON-LD document or put in ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
