地理信息 位置标识符架构 第2部分：位置标识符关联（等同ISO 19155-2:2017）

[中文适用范围]： 本文档定义了将地点标识符（PI，参见ISO 19155）与其他编码中的特征或对象相链接的三种机制：一是地理标记语言（GML）对象的 Id 属性（gml:id），定义于ISO 19136；二是通用唯一标识符（UUID），定义于IETF RFC 4122；三是统一资源定位符（URL），定义于IETF RFC 1738。上述地点标识符链接机制通过万维网联盟（W3C）XML 链接语言（XLink）中定义的 xlink:href 属性实现。虽然这些特征或对象的标识符在某些情况下可标识特定地点，但在此文档的范围内，这些来自其他编码领域的特征或对象的标识符在概念上被统称为“其他标识符”。 本文档进一步规定：当事件地点标识符依据ISO 19155规范、采用地理标记语言（GML，ISO 19136）进行编码时，应通过 gml:id 与其他GML编码的特征相链接。使用 gml:id 编码GML实例的详细信息载于规范性附录中。另有若干规范性附录分别定义了使用UUID和URL将地点标识符链接至其他标识符的编码方法，并提供了应用示例。 本文档适用于需建立地点标识符与现实或虚拟世界中对象之间关联性的各类应用领域，包括基于位置的服务、关联开放数据、机器人辅助服务等。本文档并非旨在创建与特定特征或对象相关联的地点标识符注册表；同时，除 gml:id、UUID 和 URL 之外的其他链接机制的支持，不属于本文档的适用范围。 [外文原描述]： ISO 19155-2:2017 defines the following three mechanisms for linking Place Identifiers (PIs) (see ISO 19155) to features or objects existing in other encodings: - Id attribute of a GML object (gml:id) as defined in ISO 19136; - Universally Unique Identifier (UUID) as defined in IETF RFC 4122; - Uniform Resource Locator (URL) as defined in IETF RFC 1738. These PI linking mechanisms are enabled using xlink:href as defined in W3C XML Linking Language (XLink). While the identifiers of these features or objects can sometimes identify a place, within the scope of this document, the identifiers of features or objects existing in other encoding domains are referred to conceptually as other identifiers. This document further defines that when PIs are encoded, as specified in ISO 19155, using the Geography Markup Language (GML) (ISO 19136), they are linked using gml:id to other GML encoded features. The details of encoding GML instances using gml:id are specified in a normative annex. Additional normative annexes define encodings for linking Place Identifiers to other identifiers using UUID and URL and present examples for their use. ISO 19155-2:2017 is applicable to location-based services, linked open data, robotic assisted services and other application domains that require a relationship between PIs and objects in either the real or virtual world. ISO 19155-2:2017 is not about creating a registry of Place Identifiers linked to specific features or objects, and support of linking mechanisms other than gml:id, UUID, and URL is out of the scope of this document.