The GeoPlatform Portfolio Model is the information model of business objects representing the assets of a geospatial portfolio. The core of the GeoPlatform Portfolio Model is the regp:Asset class. The GeoPlatform Asset is the general template for all 1st-class portfolio resources. The Asset model is designed as an amalgam of standard models integrating RDF, FOAF, SKOS, DCAT, PROV-O, Dublin Core, ISO-19115, and other standard elements broadly used in information technology today. In this way, GeoPlatform Portfolio Assets also align and interoperate with a broad spectrum of spatial and non-spatial applications and technologies, across multiple domains of information technology.
The core business objects of the GeoPlatform ecosystem, i.e., the key assets of a geospatial portfolio, include Datasets, Services, Layers, Maps, Galleries, and Communities. Each of these objects specialize the regp:Asset abstract class with specific properties and behaviors.
The Dataset, Service, Layer, Map, Gallery, and Community objects have basic relationships (links), as shown in the diagram below, that can be established and updated as needed.
A Dataset (dcat:Dataset) is a collection of data, published or curated by a single agent and available for access or download in one or more formats. It does not have to be available as a downloadable file but, when it is, it is encoded in a defined structure.
In the GeoPlatform ecosystem, Dataset Objects are the foundational information elements of the portfolio. They provide rich metadata about data including information identifying the dataset (title, geographic and temporal extent, publisher, etc) , its purpose, and fitness-for-use in various application contexts.
A Service (regp:Service), also called a Web Service, is a capability offered by an electronic device to another electronic device, communicating with each other via the World Wide Web. In a web service, web technology such as the HTTP, originally designed for human-to-machine communication, is utilized for machine-to-machine communication, more specifically for transferring machine readable file formats such as XML and JSON.
In the GeoPlatform ecosystem, a Service Object is generally used for accessing Datasets (as Features or Coverages), harvesting Layers, and rendering Layers.
A Layer, also called an Open Layer, is defined as a visual representation of a geographic dataset in any digital map environment. Conceptually, a layer is a slice or snapshot of the physical or conceptual geographic reality in a particular area and is symbolized using a specific style to facilitate interpretation of the information by end-users.
In the GeoPlatform ecosystem, Layers have portrayal rules that are used by applications to visualize the source data. A Layer typically has a linked relationship to a Service. Layers may also have linked relationships to their source Datasets. Layers represent the primary information elements of Map Objects.
A Map object, also called an Open Map, is defined as a visual representation of a geographic information in any digital map environment. It’s a slice or snapshot of the physical or conceptual geographic reality in a particular area and is symbolized using a specific style to facilitate interpretation of the information by end-users. A Map typically consists of a stack of Layers.
In the GeoPlatform ecosystem, Map objects come from web applications or GIS systems (e.g., ArcGIS Online, Mapbox, QGIS) and, regardless of source, are managed and behave the same way (as Open Map Objects): they can be enriched with metadata, linked to other GeoPlatform resources and other web resources, searched-for, shared, and exploited to inform and assist decision-makers to take action.
A Gallery is a container composed of portfolio items: Datasets, Services, Layers, and Maps. Galleries can also be composed of sub-galleries (for example a sub gallery for each state of USA).
In the GeoPlatform ecosystem, Gallery Objects are curated collections of related portfolio assets. Galleries can be enriched with metadata and knowledge graphs of semantically grounded terms. Galleries can shared as embedded content within community spaces and other websites.
A Community is a specialization of foaf:Group (in turn, a specialization of foaf:Agent) representing a collection of people organized together into a social, commercial or political structure. The group has some common purpose or reason for existence which goes beyond the set of people belonging to it.
In the GeoPlatform ecosystem, Community Objects are software representations of physically hosted Dynamic Digital Community spaces on the GeoPlatform. Dynamic Digital Communities enable partners to quickly build cross-agency community portals with rich dynamic geospatial content and integrated interactive applications and tools. A Community-specific Portfolio of objects can be created and managed by establishing a “usedBy” relationship to link a GeoPlatform Portfolio Object to a Community Object.
The following items are the core classes of and relating to the business objects of the GeoPlatform ecosystem (i.e.,regp:Asset):
regp:Asset – The Asset, also known as an Item (or Resource) is the top class of the item hierarchy. It is a subclass of rdfs:Resource. It represents any information entities or services that can be managed in a registery. The Asset is a generalization of the DCAT Dataset concept. It contains all the common medadata and Classifiers information about any resource of interest.
foaf:Agent (http://xmlns.com/foaf/spec/#term_Agent) – Defines a standard way to represent agents (eg. person, group, software or physical artifact) The Agent class is useful in a few places in FOAF where Person would have been overly specific.
foaf:Organization (http://xmlns.com/foaf/spec/#term_Organization) – Represents a kind of Agent corresponding to social institutions such as companies, societies etc.
rdfs:Resource (https://www.w3.org/TR/rdf-schema/#ch_resource) – Represents any RDF resource that can be referenced by any object of the model. Usually resource should have an identifier that is resolvable so you can get more information about the resource. It is good practice to provide a title and description for human readable consumption to provide some hints what the resource is about.
skos:Concept (https://www.w3.org/2009/08/skos-reference/skos.html#Concept) – Represents an idea or notion; a unit of thought. However, what constitutes a unit of thought is subjective, and this definition is meant to be suggestive, rather than restrictive. Rationale: The use of controlled vocabularies helps to organize information at the conceptual level and enable semantic inferencing and classification of information that helps the end-user to find relevant information.
id:Identifier – A mechanism to uniquely identify a resource using a given codespace and defined by an authority. Identifiers help to find items based on well-known identification systems (ISBN, for example).
regp:Classifiers – A JSON Object referring to different semantic concepts (encoded in SKOS) playing different roles in the context of the asset (primary subject, function, audience). The use of semantically grounded concepts enable the inferencing and the use of alternative labels for same units of thought. The concepts can be derived from authoritative concept schemes.
dct:Standard (http://www.dublincore.org/documents/dcmi-terms/#terms-Standard) – Provides a basis for comparison; a reference point against which other things can be evaluated.Rationale: Used to understand how register items conform to standards.
foaf:Document (http://xmlns.com/foaf/spec/#term_Document) – Represents those things which are, broadly conceived, documents. The foaf:Image class is a sub-class of Document, since all images are documents. Document needs to be identified by a resolvable URL on the web. Rationale: A way to describe documents to understand their role in the ecosystem of items managed in the registry.
dcat:Dataset (https://www.w3.org/TR/vocab-dcat/#Class:_Dataset) – A collection of data, published or curated by a single agent and available for access or download in one or more formats.
vcard:VCard (https://www.w3.org/TR/vcard-rdf/#d4e2380) – Represents contact information for a person or organization. Rationale: A standardized way to describe contact information, so persons/organizations related to resources can be contacted when necessary.
prov:Attribution (https://www.w3.org/TR/prov-o/#Attribution) – Registered resources are attributed to one or more responsibility parties playing different Attribution roles (contact point, publisher, rights holder, processor, etc.). Rationale: Used to understand the role of each contributor of a resources. Provides an extensible mechanism to accommodate new roles.
dct:Location (http://www.dublincore.org/documents/dcmi-terms/#terms-Location) – Location represents a spatial region or named place that is related to the item stored in the register. Each location should a geographic extent expressed in WGS84 to enable spatial search in consistent way. Used as the base class for Location. Rationale: Essential for spatial scoping of data. Location should be referred to as much as possible with a resolvable URI that points to a controlled vocabulary of place names (Gazetteer).
dct:PeriodOfTime (http://www.dublincore.org/documents/dcmi-terms/#terms-PeriodOfTime) – A PeriodOfTime denotes the temporal scope of a register item. dct:PeriodOfTime is the base class, and a time period has startDate and/or endDate. If they are the same, they represent a temporal instant (point in time). A PeriodOfTime can also refer to a URI that can be resolvable and is defined by a well-known taxonomy of periods of time. Rationale: Essential for temporal scoping of data.
dct:RightsStatement (http://dublincore.org/documents/dcmi-terms/#terms-RightsStatement) – A statement about the intellectual property rights (IPR) held in or over a resource, a legal document giving official permission to do something with a resource, or a statement about access rights. Rationale: Important legal information protecting intellectual property.