JSON-LD

RDF

RDF用于信息需要被应用程序处理而不是仅仅显示给人观看的场合。RDF提供了一种用于表达这一信息、并使其能在应用程序间交换而不丧失语义的通用框架。既然是通用框架，应用程序设计者可以利用现成的通用RDF解析器（RDF parser）以及通用的处理工具。能够在不同的应用程序间交换信息意味着对于那些并非信息的最初创建者的应用程序也是可利用这些信息。

Detail in RDF入门推荐标准

Link Data

Linked Data [LINKED-DATA] is a way to create a network of standards-based machine interpretable data across different documents and Web sites. It allows an application to start at one piece of Linked Data, and follow embedded links to other pieces of Linked Data that are hosted on different sites across the Web.

JSON_LD

JSON-LD is a serialization format for Linked Data based on JSON.

JSON-LD is a lightweight syntax to serialize Linked Data in JSON [RFC4627]. Its design allows existing JSON to be interpreted as Linked Data with minimal changes. JSON-LD is primarily intended to be a way to use Linked Data in Web-based programming environments, to build interoperable Web services, and to store Linked Data in JSON-based storage engines. Since JSON-LD is 100% compatible with JSON, the large number of JSON parsers and libraries available today can be reused. In addition to all the features JSON provides, JSON-LD introduces:

• a universal identifier mechanism for JSON objects via the use of IRIs,
• a way to disambiguate keys shared among different JSON documents by mapping them to IRIs via a context,
• a mechanism in which a value in a JSON object may refer to a JSON object on a different site on the Web,
• the ability to annotate strings with their language,
• a way to associate datatypes with values such as dates and times,
• and a facility to express one or more directed graphs, such as a social network, in a single document.

Detail in http://www.w3.org/TR/json-ld/

Coverage Data

A coverage is the digital representation of some spatio-temporal phenomenon.
define in Coverage Data:feature that acts as a function to return values from its range for any direct position within its spatial, temporal or spatiotemporal domain
Coverage Data examples:like grids, time series, and vertical profiles, distinguished by the geometry of their spatiotemporal domain.

Coverage JSON

CoverageJSON is a data format for publishing coverage data to the web in a web-friendly way.

CoverageJSON is a format for encoding coverage data like grids, time series, and vertical profiles, distinguished by the geometry of their spatiotemporal domain.

Detail in CoverageJSON Specification

Resolving domain and range URLs

Domain axis values and range values SHOULD not be exposed as linked data since they are currently not suitable for such representation. !!-_-

When sending HTTP requests, the Accept header SHOULD be set appropriately to the CoverageJSON media type(application/prs.coverage+json).